SPECIFICATION TITLE OF THE INVENTION: NON-AQUEOUS ELECTROLYTIC SOLUTION, ELECTROCHEMICAL ELEMENT USING SAME, AND ALKYNYL COMPOUND USED THEREFOR TECHNICAL FIELD [0001] The present invention relates to a nonaqueous electrolytic solution, an electrochemical element using it, and a novel alkynyl compound used for electrochemical elements, etc. BACKGROUND ART [0002] In recent years, lithium secondary batteries have been widely used as power supplies for small-sized electronic devices such as mobile telephones, notebook-size personal computers and the like, power supplies for electric vehicles, as well as for electric power storage, etc. These electronic devices and vehicles may be used in a broad temperature range, for example, at midsummer high temperatures or at frigid low temperatures, and are therefore required to be improved in point of the battery performance such as well-balanced cycle properties and/or high-temperature charging storage properties in a broad temperature range. A lithium secondary battery is mainly constituted of a positive electrode and a negative electrode containing a material capable of absorbing and releasing lithium, and a nonaqueous electrolytic solution containing a lithium salt and a nonaqueous solvent. For the nonaqueous solvent, used are carbonates such as ethylene carbonate (EC), propylene carbonate (PC), etc. As the negative electrode, known are metal lithium, and metal compounds (metal elemental substances, oxides, alloys with lithium, etc.) and carbon materials capable of absorbing and releasing lithium In particular, a lithium secondary battery using a carbon material capable of absorbing and releasing lithium, such as coke, artificial graphite, natural graphite or the like, has been widely put into practical use. [0003] For example, it is known that, in a lithium secondary battery using a highly-crystalline carbon material such as natural graphite, artificial graphite or the like as the negative electrode material therein, the decomposed product or gas generated through reductive decomposition of the solvent in the nonaqueous electrolytic solution on the surface of the negative electrode during charging detracts from the electrochemical reaction favorable for the battery, therefore worsening the cycle properties and/or the high-temperature charging storage properties of the battery. Deposition of the decomposed product of the nonaqueous solvent interferes with smooth absorption and release of lithium by the negative electrode, and therefore, in particular, the cycle properties at low temperatures and high temperatures and/or the load characteristics after high-temperature charging storage may be thereby often worsened. In addition, it is known that a lithium secondary battery using a lithium metal or its alloy, or a metal elemental substance such as tin, silicon or the like or its metal oxide as the negative electrode material therein may have a high initial battery capacity but its battery performance such as cycle properties and/or load characteristics after high-temperature charging storage greatly worsens, since the micronized powdering of the material is promoted during cycles thereby bringing about accelerated reductive decomposition of the nonaqueous solvent, as compared with the negative electrode of a carbon material. In addition, the micronized powdering of the negative electrode material and the deposition of the decomposed product of the nonaqueous solvent may interfere with smooth absorption and release of lithium by the negative electrode, and therefore, in particular, the cycle properties at low temperatures and at high temperatures may be thereby often worsened. [0004] On the other hand, it is known that, in a lithium secondary battery using, for example, LiCo02, LiMn204, LiNi02 or LiFeP04 as the positive electrode, when the nonaqueous solvent in the nonaqueous electrolytic solution is heated at a high temperature in the charged state, the decomposed product or the gas thereby locally generated through partial oxidative decomposition in the interface between the positive electrode material and the nonaqueous electrolytic solution interferes with the electrochemical reaction favorable for the battery, and therefore the battery performance such as cycle properties and/or load characteristics after high-temperature charging storage is thereby also worsened. [0005] As in the above, the decomposed product and the gas generated through decomposition of the nonaqueous electrolytic solution on the positive electrode or the negative electrode may interfere with the movement of lithium ions or may swell the battery, and the battery performance is thereby worsened. Despite the situation, electronic appliances equipped with lithium secondary batteries therein are offering more and more an increasing range of functions and are being in a stream of further increase in power consumption. With that, the capacity of lithium secondary batteries is being much increased, and the space volume for the nonaqueous electrolytic solution in the battery is decreased by increasing the density of the electrode and by reducing the useless space volume in the battery. Accordingly, the situation is that even decomposition of only a small amount of the nonaqueous electrolytic solution may worsen the battery performance such as cycle properties at low temperatures and high temperatures and/or load characteristics after high-temperature charging storage. [0006] As a lithium primary battery, for example, known is one in which the positive electrode is formed of manganese dioxide or fluorographite and the negative electrode is formed of lithium metal, and the lithium primary battery of the type is widely used as having a high energy density, for which, however, it is desired to prevent the increase in the internal resistance and to improve the low-temperature and high-temperature cycle properties, and to prevent the increase in the internal resistance during long-term storage to thereby improve the long-term storability at high temperatures. Recently, further, as a novel power source for electric vehicles or hybrid electric vehicles, electric storage devices have been developed, for example, an electric double layer capacitor using activated carbon or the like as the electrode from the viewpoint of the output density thereof, and a hybrid capacitor including a combination of the electric storage principle of a lithium ion secondary battery and that of an electric double layer capacitor (an asymmetric capacitor where both the capacity by lithium absorption and release and the electric double layer capacity are utilized) from the viewpoint of both the energy density and the output density thereof; and it is desired to improve the battery performance such as the cycle properties at low temperatures and high temperatures and/or the load characteristics after high-temperature charging storage of these capacitors. [0007] Patent Reference 1 discloses a lithium ion secondary battery using an electrolytic solution that contains a carbonate compound having both a carbon-carbon triple bond and a non-aromatic carbon-carbon double bond in the molecule, saying that the battery is excellent in cycle properties and high-temperature storage properties. Patent Reference 2 discloses a lithium ion secondary battery, in which 2-butyne-l,4-diol dimethanesulfonate is added to the electrolytic solution in an amount of 1% by weight of the solution, saying that the cycle properties of the battery at 20°C are thereby improved. CITATION LIST PATENT REFERENCES [0008] Patent Reference 1: JP-A 2009-193836 Patent Reference 2: JP-A 2000-195545 DISCLOSURE OF THE INVENTION PROBLEMS THAT THE INVENTION IS TO SOLVE [0009] An object of the present invention is to provide an excellent nonaqueous electrolytic solution capable of improving low-temperature and high-temperature cycle properties and load characteristics after high-temperature charging storage, an electrochemical element using it, and an alkynyl compound used for it. MEANS FOR SOLVING THE PROBLEMS [0010] The present inventors have investigated in detail the performance of the nonaqueous electrolytic solutions in the above-mentioned prior art. As a result, the actual situation is that the nonaqueous electrolytic solution in the Patent Reference 1 and others could not obtain good cycle properties in a broad range of low temperatures and high temperatures. In addition, the actual situation is that the nonaqueous electrolytic solution in Patent Reference 2 and others could not sufficiently satisfy the load characteristics after high-temperature charging storage. Given the situation, the present inventors have assiduously studied for the purpose of solving the above-mentioned problems, and have found that, when an alkynyl compound having a specific structure of bonding the alkynyl group to the compound via a specific group is added to a nonaqueous electrolytic solution, then the electrolytic solution can improve cycle properties at low temperatures and high temperatures and load characteristics after high-temperature charging storage, and have completed the present invention. [0011] Specifically, the present invention provides the following (1) to (5) : (1) A nonaqueous electrolytic solution of an electrolyte salt dissolved in a nonaqueous solvent, which comprises at least one alkynyl compound represented by the following general formula (I) in an amount of from 0.01 to 10% by mass of the nonaqueous electrolytic solution: [0012] [Chemical Formula 1] [0013] (In the formula, X1 represents a group -C(=0)-, a group -C(=0)-C(=0)-, a group -S(=0)2-, a group -P(=0) (-R1) -, or a group -X1-S(=0)20- (where X1 represents an alkylene group having from 1 to 8 carbon atoms, or a divalent linking group having from 2 to 8 carbon atoms and containing at least one ether bond) ; R1 represents an alkenyl group having from 2 to 8 carbon atoms, a formyl group, an alkyl group having from 1 to 8 carbon atoms, an acyl group having from 2 to 8 carbon atoms, an arylcarbonyl group having from 7 to 15 carbon atoms, an alkanesulfonyl group having from 1 to 8 carbon atoms, an alkynyloxysulfonyl group having from 3 to 8 carbon atoms, an arylsulfonyl group having from 6 to 15 carbon atoms, a dialkylphosphoryl group having from 2 to 16 carbon atoms, an alkyl (alkoxy) phosphoryl group having from 2 to 16 carbon atoms, or a dialkoxyphosphoryl group having from 2 to 16 carbon atoms; R1 represents an alkynyl group having from 3 to 8 carbon atoms, or an alkynyloxy group having from 3 to 8 carbon atoms; R1 represents an alkyl group having from 1 to 8 carbon atoms, an alkenyl group having from 2 to 8 carbon atoms, an alkynyl group having from 3 to 8 carbon atoms, an aryl group having from 6 to 18 carbon atoms, an alkoxy group having from 1 to 8 carbon atoms, an alkenyloxy group having from 2 to 8 carbon atoms, an alkynyloxy group having from 3 to 8 carbon atoms, or an aryloxy group having from 6 to 18 carbon atoms; n indicates 0 or 1; provided that when X is a group -C{=0)-, then n is 1, R""^ is an alkenyl group having from 2 to 8 carbon atoms, and R is an alkynyl group having from 3 to 8 carbon atoms, when X is a group -C(=0)-C(=0) -, a group -S(=0)2-, or a group -P(=0) (-R)-, then n is 1, R is an alkenyl group having from 2 to 8 carbon atoms, and R is an alkynyloxy group having from 3 to 8 carbon atoms, and when X is a group -X-S (=0) 2O-, then R is an alkynyl group having from 3 to 8 carbon atoms). [0014] (2) The nonaqueous electrolytic solution of the above (1) , wherein the alkynyl compound and represented by the general formula (I) is an alkynyl sulfonate compound represented by the following general formula (III): [Chemical Formula 2] [0015] (In the formula, X* represents an alkylene group having from 1 to 8 carbon atoms, or a divalent linking group having from 2 to 8 carbon atoms and containing at least one ether bond; R represents a formyl group, an alkyl group having from 1 to 8 carbon atoms, an acyl group having from 2 to 8 carbon atoms, an arylcarbonyl group having from 7 to 15 carbon atoms, an alkanesulfonyl group having from 1 to 8 carbon atoms, an alkynyloxysulfonyl group having from 3 to 8 carbon atoms, an arylsulfonyl group having from 6 to 15 carbon atoms, a dialkylphosphoryl group having from 2 to 16 carbon atoms, an alkyl {alkoxy)phosphoryl group having from 2 to 16 carbon atoms, or a dialkoxyphosphoryl group having from 2 to 16 carbon atoms; R^ represents an alkynyl group having from 3 to 8 carbon atoms; m indicates 0 or 1; provided that when m is 1, then R is a formyl group, an alkyl group having from l to 8 carbon atoms, an acyl group having from 2 to 8 carbon atoms, an arylcarbonyl group having from 7 to 15 carbon atoms, an alkanesulfonyl group having from 1 to 8 carbon atoms, an arylsulfonyl group having from 6 to 15 carbon atoms, a dialkylphosphoryl group having from 2 to 16 carbon atoms, an alkyl {alkoxy)phosphoryl group having from 2 to 16 carbon atoms, or a dialkoxyphosphoryl group having from 2 to 16 carbon atoms; at least one hydrogen atom on the carbon atom of R^, X* and R^ may be substituted with a halogen atom). [0016] (3) An electrochemical element comprising a positive electrode, a negative electrode, and a nonaqueous electrolytic solution of an electrolyte salt dissolved in a nonaqueous solvent, wherein the nonaqueous electrolytic solution comprises at least one alkynyl compound represented by the above-mentioned general formula (I) in an amount of from 0.01 to 10% by mass of the nonaqueous electrolytic solution. (4) An alkynyl compoiind represented by the following general formula (II): [0017] [Chemical Formula 3] [0018] (In the formula, X represents a group -S(=0)2-, or a group-X-S (=0) 2O- (where X represents an alkylene group having from 1to 8 carbon atoms, or a divalent linking group having from 2 to 8 carbon atoms and containing at least one ether bond). R* represents an alkenyl group having from 2 to 8 carbon atoms or an alkenyloxy group having from 2 to 8 carbon atoms; and R^ represents an alkynyl group having from 3 to 8 carbon atoms, or an alkynyloxy group having from 3 to 8 carbon atoms.) (5) An alkynyl sulfonate compound represented by the following general formula (III): [0019] [Chemical Formula 4] (In the formula, X*, R and R' have the same meanings as mentioned above.) ADVANTAGE OF THE INVENTION [0020] According to the present invention, there are provided an excellent nonaqueous electrolytic solution capable of improving battery performance such as low-temperature and high-temperature cycle properties and load characteristics after high-temperature charging storage, an electrochemical element using it, and an alkynyl compound used for it. BEST MODE FOR CARRYING OUT THE INVENTION [0021] [Nonaqueous Electrolytic Solution] The nonaqueous electrolytic solution of the present invention comprises an electrolyte salt dissolved in a nonaqueous solvent, and comprises at least one alkynyl compound represented by the following general formula (I) in an amount of from 0.01 to 10% by mass of the nonaqueous electrolytic solution: [0022] [Chemical Formula 5] (In the formula, X, R, R and n have the same meanings as mentioned above.) [0023] The nonaqueous electrolytic solution of the present invention can improve battery performance such as low-temperature and high-temperature cycle properties and load characteristics after high-temperature charging storage. Though not clear, the reason may be considered as follows: The alkynyl compound represented by the general formula (I) in the present invention has a specific electron-attracting group and a carbon-carbon triple bond-containing group, and further has still another functional group, and is therefore considered to form a low-resistance surface film having high heat resistance and to specifically improve low-temperature and high-temperature cycle properties and load characteristics after high-temperature charging storage. In the alkynyl compound represented by the general formula (I) in the present invention, in case where X""" is a group -C(=0)-, a group -C(=0)-C(=0)-, a group -S(=0)2- or a group -P(=0) (-R^) -, the compound has a structure in which the unsaturated bond or ether bond-containing group bonds to the carbon-carbon triple bond-containing group (alkynyl group or alkynyloxy group) via the above-mentioned specific functional group therebetween, and in this, therefore, it is considered that the reductive decomposition at the two multiple bond sites would go on more easily. As a result, a good mixture surface film that could not be expected in the case where the carbonate compound described in Patent Reference 1 is used could be formed to exhibit the effect of specifically improving the above-mentioned battery performance. Above all, it has been confirmed that, in the case where X^ is a group -S(=0)2-, an especially good mixture surface film can be formed to enhance the effect of improving the low-temperature and high-temperature cycle properties and the load characteristics after high-temperature charging storage. This is considered because the electron attractivity of the group -S(=0)2- could further promote the reductive decomposition at the multiple bond sites to thereby facilitate the formation of the polymerization surface film derived from the above-mentioned multiple bonds. [0024] Also in the case where the alkynyl compound represented by the general formula (I) is an alkynyl sulfonate compound represented by the following general formula (III), the low-temperature and high-temperature cycle properties and the load characteristics after high-temperature charging storage can be improved, like in the above. [0025] [Chemical Formula 6] (In the formula, X , R and R have the same meanings as mentioned above.) [0026] Though not clear, the reason why the nonaqueous electrolytic solution containing the alkynyl sulfonate compound represented by the general formula (III) can improve the low-temperature and high-temperature cycle properties and the load characteristics after high-temperature charging storage may be considered as follows: Specifically, in the alkynyl sulfonate compound represented by the general formula (III), two different substituents of one specific substituent selected from an ether group (-0-), a formyl group (-C(=0)H), an acyl group (-C(=0)R) , a sulfonyl group (-S(=0)2R) and a phosphoryl group {-S(=0)20R') are bonded to each other via a hydrocarbon group optionally containing an oxygen atom at the terminal and/or in the intermediate thereof, and therefore the compound has a reduction potential quite different from that of the compound of 2-butyne-l,4-diol dimethanesulfonate having a triple bond in the linking chain to link the two substituents therein, as described in Patent Reference 2. The alkynyl sulfonate compound represented by the general formula (III) has the triple bond-having specific sulfonate group (-S(=0)20R^) at the terminal thereof, and therefore the surface film containing the component derived from the above-mentioned two substituents is not formed excessively on the electrode, and consequently, it may be considered that a low-resistance surface film having high heat resistance that could not be expected in the case where the compo\ind described in Patent Reference 2 is used can be formed to exhibit the effect of specifically improving the low-temperature and high-temperature cycle properties and the load characteristics after high-temperature charging storage. [0027] (Alkynyl Compound Represented by General Formula (I)) [0028] [Chemical, Formula 7] [0029] In the general formula (I) , X represents a group -C (=0) - , a group -C(=0)-C(=0)-, a group -S(=0)2-, a group -P(=0) (-R)-, or a group -X^-S(=0)20- (where X represents an alkylene group having from 1 to 8 carbon atoms, or a divalent linking group having from 2 to 8 carbon atoms and containing at least one ether bond). In the group -X^-S (=0) 2O- , the alkylene group having from 1 to 8 carbon atoms of X is preferably an alkylene group having from 1 to 4 carbon atoms, more preferably from 1 to 3 carbon atoms, even more preferably 2 or 3 carbon atoms, and is especially preferably an alkylene group having 2 carbon atoms. The divalent linking group having from 2 to 8 carbon atoms and containing at least one ether bond is preferably -CH2OCH2-, -C2H4OC2H4-, or -C2H4OC2H4OC2H4-, more preferably -C2H4OC2H4-. The alkylene group having from 1 to 8 carbon atoms, or the divalent linking group having from 2 to 8 carbon atoms and containing at least one ether bond of X^ is described in detail in the section of the alkynyl sulfonate compound represented by the general formula (III) to be mentioned below. [0030] In the general formula (I) , for the linear or branched alkenyl group having from 2 to 8 carbon atoms represented by R""^, preferably mentioned are a linear alkenyl group such as a vinyl group, a 2-propenyl group, a 2-butenyl group, a 3-butenyl group, a 4-pentenyl group, a 5-hexenyl group, etc. ; and a branched alkenyl group such as a 1-methyl-2-propenyl group, a 1-methyl-2-butenyl group, a 1,1-dimethyl-2-propenyl group, etc. Of those, as the alkenyl group represented by R, preferred are a vinyl group, a 2-propenyl group, a 2-butenyl group, a 3-butenyl group, a 1-methyl-2-propenyl group and a 1,1-dimethyl-2-propenyl group; more preferred are a vinyl group, a 2-propenyl group and a 3-butenyl group; and even more preferred are a vinyl group and a 2-propenyl group. [0031] In the general formula (I) , the formyl group, the alkyl group having from 1 to 8 carbon atoms, the acyl group having from 2 to 8 carbon atoms, the arylcarbonyl group having from 7 to 15 carbon atoms, the alkanesulfonyl group having from 1 to 8 carbon atoms, the alkynyloxysulfonyl group having from 3 to 8 carbon atoms, the arylsulfonyl group having from 6 to 15 carbon atoms, the dialkylphosphoryl group having from 2 to 16 carbon atoms, the alkyl (alkoxy)phosphoryl group having from 2 to 16 carbon atoms and the dialkoxyphosphoryl group having from 2 to 16 carbon atoms represented by R are described in detail in the section of the alkynyl sulfonate compound represented by the general formula (III) to be mentioned below. [0032] In the general formula (I) , for the linear or branched alkynyl group having from 3 to 8 carbon atoms represented by R^, preferably mentioned are a linear alkynyl group such as a 2-propynyl group, a 2-butynyl group, a 3-butynyl group, a 4-pentynyl group, a 5-hexynyl group, etc.; and a branched alkynyl group such as a 1-methyl-2-propynyl group, a 1-methyl-2-butynyl group, a 1,1-dimethyl-2-propynyl group, etc. Of those, as the alkynyl group represented by R, preferred is an alkynyl group having from 3 to 5 carbon atoms; more preferred are a 2-propynyl group, a 3-butynyl group, a 1-methyl-2-propynyl group and a 1,1-dimethyl-2-propynyl group; and especially preferred are a 2-propynyl group and a 1,1-dimethyl-2-propynyl group. [0033] In the general formula (I) , for the linear or branched alkynyloxy group having from 3 to 8 carbon atoms represented by R^, preferably mentioned are a linear alkynyloxy group such as a 2-propynyloxy group, a 2-butynyloxy group, a 3-butynyloxy group, a 4-pentynyloxy group, a 5-hexynyloxy group, etc. ; and a branched alkynyloxy group such as a 1-methyl-2-propynyloxy group, a 1-methyl-2-butynyloxy group, a 1,1-dimethyl-2-propynyloxy group, etc. Of those, as the alkynyloxy group represented by R^, preferred is an alkynyloxy group having from 3 to 5 carbon atoms; more preferred are a 2-propynyloxy group, a 3-butynyloxy group, a 1-methyl-2-butynyloxy group, and a 1,1-dimethyl-2-propynyloxy group; and especially preferred are a 2-propynyloxy group and a 1, l-dimethyl-2-propynyloxy group. [0034] In the general formula (I) , for the linear or branched alkyl group having from 1 to 8 carbon atoms represented by R, preferably mentioned are a linear alkyl group such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, etc.; and a branched alkyl group such as an isopropyl group, a sec-butyl group, a tert-butyl group, a tert-pentyl group, etc. Of those, as the alkyl group represented by R, preferred are a methyl group and an ethyl group, and more preferred is a methyl group. [0035] In the general formula (I) , for the linear or branched alkenyl group having from 2 to 8 carbon atoms represented by R^, preferably mentioned are a linear alkenyl group such as a vinyl group, a 2-propenyl group, a 2-butenyl group, a 3-butenyl group, a 4-pentenyl group, a 5-hexenyl group, etc. ; and a branched alkenyl group such as a 1-methyl-2-propenyl group, a 1-methyl-2-butenyl group, a 1,1-dimethyl-2-propenyl group, etc. Of those, as the alkenyl group represented by R, preferred are a vinyl group, a 2-propenyl group, a 2-butenyl group, a 3-butenyl group, a 1-methyl-2-propenyl group, and a 1,1-dimethyl-2-propenyl group; more preferred are a vinyl group, a 2-propenyl group and a 3-butenyl group; and most preferred are a vinyl group and a 2-propenyl group. [0036] In the general formula (I) , for the linear or branched alkynyl group having from 3 to 8 carbon atoms represented by R, preferably mentioned are a linear alkynyl group such as a 2-propynyl group, a 2-butynyl group, a 3-butynyl group, a 4-pentynyl group, a 5-hexynyl group, etc.; and a branched alkynyl group such as a 1-methyl-2-propynyl group, a 1-methyl-2-butynyl group, a 1,1-dimethyl-2-propynyl group, etc. Of those, as the alkynyl group represented by R^, preferred is an alkynyl group having from 3 to 5 carbon atoms; more preferred are a 2-propynyl group, a 3-butynyl group, a 1-methyl-2-propynyl group, and a 1,1-dimethyl-2-propynyl group; and more preferred are a 2-propynyl group and a 1,1-dimethyl-2-propynyl group. [0037] In the general formula (I), for the aryl group having from 6 to 18 carbon atoms represented by R^, preferably mentioned are a phenyl group, a tolyl group, a xylyl group, and a naphthyl group. Of those, as the aryl group represented by R, preferred are a phenyl group and a tolyl group; and more preferred is a phenyl group. [0038] In the general formula (I) , for the linear or branched alkoxy group having from 1 to 8 carbon atoms represented by R^, preferably mentioned a linear alkoxy group such as a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, etc.; and a branched alkoxy group such as an isopropyloxy group, a sec-butyloxy group, a tert-butyloxy group, a tert-pentyloxy group, etc. Of those, as the alkoxy group represented by R, preferred are a methoxy group and an ethoxy group; and more preferred is an ethoxy group. [0039] In the general formula (I) , for the linear or branched alkenyloxy group having from 2 to 8 carbon atoms represented by R^, preferably mentioned are a linear alkenyloxy group such as a vinyloxy group, a 2-propenyloxy group, a 2-butenyloxy group, a 3-butenyloxy group, a 4-pentenyloxy group, etc.; and a branched alkenyloxy group such as a 2-methyl-2-propenyloxy group, a 2-methyl-2-butenyloxy group, a 3-methyl-2-butenyloxy group, etc. Of those, as the alkenyloxy group represented by R^, preferred are a vinyloxy group and a 2-propenyloxy group; and more preferred is a 2-propenyloxy group. [0040] In the general formula (I) , for the linear or branched alkynyloxy group having from 3 to 8 carbon atoms represented by R, preferably mentioned are a linear alkynyloxy group such as a 2-propynyloxy group, a 2-butynyloxy group, a 3-butynyloxy group, a 4-pentynyloxy group, a 5-hexynyloxy group, etc.; and a branched alkynyloxy group such as a 1-methyl-2-propynyloxy group, a 1-methyl-2-butynyloxy group, a 1,1-dimethyl-2-propynyloxy group, etc. Of those, as the alkynyloxy group represented by R'^, preferred is an alkynyloxy group having from 3 to 5 carbon atoms; more preferred are a 2-propynyloxy group, a 3-butynyloxy group, a 1-methyl-2-butynyloxy group, and a 1,1-dimethyl-2-propynyloxy group; even more preferred are a 2-propynyloxy group and a 1,1-dimethyl-2-propynyloxy group. [0041] In the general formula (I) , for the aryloxy group having from 6 to 18 carbon atoms represented by R, preferably mentioned are a phenyloxy group, a tolyloxy group, a xylyloxy group, and a naphthyloxy group. Of those, as the aryloxy group represented by R, preferred are a phenyloxy group and a tolyloxy group, and more preferred is a phenyloxy group. [0042] In case where X-"- in the general formula (I) is is-a group -S{=0)2-f the combination of the group R(0)n and the group R therein includes the following (a) to (d): (a) a combination of an alkenyl group (or that is, in the case of n = 0) and an alkynyl group, (b) a combination of an alkenyl group (or that is, in the case of n = 0) and an alkynyloxy group, (c) a combination of an alkenyloxy group (or that is, in the case of n = 1) and an alkynyl group, (d) a combination of an alkenyloxy group (or that is, in the case of n = 1) and an alkynyloxy group. Of those, preferred is the case where the combined substituents (group R''"(0)n, group R) have one oxygen atom, especially the case where R is an alkynyloxy group, since the low-temperature and high-temperature cycle properties and the load characteristics after high-temperature charging storage are bettered more. In case where X is a group -P(=0) (-R^) -, preferably, the combined siibstituents R(0)n, R and R have from 1 to 3 oxygen atoms, more preferably 3 oxygen atoms, since the low-temperature and high-temperature cycle properties and the load characteristics after high-temperature charging storage are bettered more. [0043] In case where X^ in the general formula (I) is a group -P(=0) (-R)-, the combination of the unsaturated bond-having substituents R(0)n, R and R includes the following (x) to (z) : (x) a combination of one carbon-carbon double bond-having group (alkenyl group or alkenyloxy group) and one carbon-carbon triple bond-having group (alkynyl group or alkynyloxy group),(y) a combination of one carbon-carbon double bond-having group (alkenyl group or alkenyloxy group) and two carbon-carbon triple bond-having groups (alkynyl group or alkynyloxy group),(z) a combination of two carbon-carbon double bond-having groups (alkenyl group or alkenyloxy group) and one carbon-carbon triple bond-having group (alkynyl group or alkynyloxy group). Of those, preferred is the combination (x) or (y) and more preferred is the combination (x) , since the low-temperature and high-temperature cycle properties and the load characteristics after high-temperature charging storage are bettered more. [0044] The following are preferred examples of the compound represented by the general formula (I). As the case where X is a group -C(=0) -, R is an alkynyl group and n is 1, preferably mentioned are alkynoates such as vinyl 3-butynoate, 2-propenyl 3-butynoate, 3-butenyl 3-butynoate, vinyl 4-pentynoate, 2-propenyl 4-pentynoate, 3-butenyl 4-pentynoate, etc. Of those, preferred are vinyl 3-butynoate and 2-propenyl 3-butynoate; and more preferred is 2-propenyl 3-butynoate. [0045] As the case where X^ is a group -C(=0)-C{=0)-, R^ is an alkynyloxy group and n is 1, preferably mentioned are oxalates such as 2-propynyl vinyl oxalate, 3-butynyl vinyl oxalate, 2-propenyl 2-propynyl oxalate, 3-butynyl 2-propenyl oxalate, 3-butenyl 2-propynyl oxalate, 3-butenyl 3-butynyl oxalate, etc. Of those, preferred are 2-propynyl vinyl oxalate and 2-propenyl 2-propynyl oxalate; and more preferred is 2-propenyl 2-propynyl oxalate. [0046] As the case where X is a group -S (=0) 2-, R is an alkynyl group and n is 0, preferably mentioned are sulfonyl compounds such as 2-propynyl vinyl sulfone, 2-propenyl 2-propynyl sulfone, 3-butenyl 2-propynyl sulfone, 3-butenyl 2-propynyl sulfone, 1,1-dimethyl-2-propynyl vinyl sulfone. 1,1-dimethyl-2-propynyl 2-propenyl sulfone, etc. Of those, preferred are 2-propynyl vinyl sulfone and 2-propenyl 2-propynyl sulfone; and more preferred is 2-propenyl 2-propynyl sulfone. [0047] As the case where X^ is a group -S(=0)2-, R is an alkynyloxy group and n is 0, preferably mentioned are sulfonates such as 2-propynyl vinyl sulfonate, 3-butynyl vinylsulfonate, 1,1-dimethyl-2-propynyl vinylsulfonate, 2-propynyl 2-propene-1-sulfonate, 3-butynyl 2-propene-1-sulfonate, 1-methyl-2-propynyl 2-propene-1-sulfonate, 1,1-dimethyl-2-propynyl 2-propene-1-sulfonate, etc. Of those, preferred are 2-propynyl vinylsulfonate and 1,1-dimethyl-2-propynyl vinylsulfonate; and more preferred is 2-propynyl vinylsulfonate. [0048] As the case where X^ is a group -S(=0)2-, R is an alkynyl group and n is 1, preferably mentioned are sulfonates such as vinyl 2-propyne-l-sulfonate, vinyl 1,1-dimethyl-2-propyne-l-sulfonate, 2-propenyl 2-propyne-l-sulfonate, 2-propenyl 1,1-dimethyl-2-propyne-l-sulfonate, 3-butenyl 2-propyne-l-sulfonate, 3-butenyl 1,1-dimethyl-2-propyne-l-sulfonate, etc.Of those, preferred are vinyl 2-propyne-l-sulfonate and 2-propenyl 2-propyne-l-sulfonate; and more preferred is 2-propenyl 2-propyne-1-sulfonate. [0049] As the case where X^ is a group -S(=0)2-, R^ is an alkynyloxy group and n is 1, preferably mentioned are sulfates such as 2-propenyl 2-propynylsulfate, 2-propenyl 1,l-dimethyl-2-propynylsulfate, 3-butenyl 2-propynylsulfate, 3-butenyl 1,1-dimethyl-2-propynylsulfate, etc. Of those, preferred are 2-propenyl 2-propynylsulfate and 2-propenyl 1,l-dimethyl-2-propynylsulfate; and more preferred is 2-propenyl 2-propynylsulfate. [0050] As the case where X^ is a group -P(=0) (-R^)-, R^ is an alkynyl group and n is 0, preferably mentioned are phosphine oxides such as methyl (2-propynyl) (vinyl)phosphine oxide, divinyl (2-propynyl)phosphine oxide, di(2-propynyl) (vinyl)phosphine oxide, di (2-propenyl) (2-propynyl)phosphine oxide, di(2-propynyl) (2-propenyl)phosphine oxide, di(3-butenyl) (2-propynyl)phosphine oxide, di(2-propynyl) (3-butenyl)phosphine oxide, etc. Of those, preferred are divinyl (2-propynyl)phosphine oxide and di (2-propynyl) (vinyl)phosphine oxide; and more preferred is divinyl (2-propynyl)phosphine oxide. [0051] As the case where X is a group -P(=0) (-R)-, R is an alkynyloxy group and n is 0, preferably mentioned are phosphinates such as 2-propynyl methyl(2-propenyl)phosphinate, 2-propynyl 2-butenyl(methyl)phosphinate, 2-propynyl di (2 -propenyl) phosphinate, 2 –propynyl di(3-butenyl)phosphinate, 1,1-dimethyl-2-propynyl methyl(2-propenyl)phosphinate, 1,1-dimethyl-2-propynyl 2-butenyl(methyl)phosphinate, 1,1-dimethyl-2-propynyl di(2-propenyl)phosphinate, 1,1-dimethyl-2-propynyl di(3-butenyl)phosphinate, etc. Of those, preferred are 2-propynyl di(2-propenyl)phosphinate and 1,1-dimethyl-2-propynyl di(2-propenyl)phosphinate; and more preferred is 2-propynyl di (2 -propenyl) phosphinate. Also preferably mentioned are phosphonates such as methyl 2-propynyl 2-propenylphosphonate, methyl 2-propynyl 2-butenylphosphonate, 2-propynyl 2-propenyl 2-propenylphosphonate, 3-butenyl 2-propynyl 3-butenylphosphonate, 1,l-dimethyl-2-propynyl methyl 2-propenylphosphonate, 1,1-dimethyl-2-propynyl methyl 2-butenylphosphonate, 1,1-dimethyl-2-propynyl 2-propenyl 2-propenylphosphonate, 3-butenyl 1,1-dimethyl-2-propynyl 3-butenylphosphonate, etc. Of those, preferred are 2-propynyl 2-propenyl 2-propenylphosphonate and 1,1-dimethyl-2-propynyl 2-propenyl 2-propenylphosphonate; and more preferred is 2-propynyl 2-propenyl 2-propenylphosphonate. [0052] As the case where X-"- is a group -P(=0) (-R)-, R is an alkynyl group and n is 1, preferably mentioned are phosphinates such as 2-propenyl methyl(2-propynyDphosphinate, 3-butenyl methyl(2-propynyl)phosphinate, 2-propenyl di(2-propynyl)phosphinate, 3-butenyl di(2-propynyl)phosphinate, 2-propenyl 2-propynyl(2-propenyl)phosphinate, 3-butenyl 2-propynyl(2-propenyl)phosphinate, etc. Of those, preferred are 2-propenyl di(2-propynyl)phosphinate and 2-propenyl 2-propynyl(2-propenyl)phosphonate; and more preferred is 2-propenyl 2-propynyl(2-propenyl)phosphinate. Also preferably mentioned are phosphonates such as 2-propynyl 2-propenyl methylphosphonate, 3-butenyl 2-propynyl methylphosphonate, 1,1-dimethyl-2-propynyl 2-propenyl methylphosphonate, 3-butenyl 1,1-dimethyl-2-propynyl methylphosphonate, 2-propynyl 2-propenyl ethylphosphonate, 3-butenyl 2-propynyl ethylphosphonate, 1,1-dimethyl-2-propynyl 2-propenyl ethylphosphonate, 3-butenyl 1,1-dimethyl-2-propynyl ethylphosphonate, etc. Of those, preferred are 2-propynyl 2-propenyl methylphosphonate and 2-propynyl 2-propenyl ethylphosphonate; and more preferred is 2-propynyl 2-propenyl methylphosphonate. [0053] As the case where X is a group -P{=0) (-R)-, R is an alkynyloxy group and n is 1, preferably mentioned are phosphates such as methyl 2-propenyl 2-propynyl phosphate. ethyl 2-propenyl 2-propynyl phosphate, 2-butenyl methyl 2-propynyl phosphate, 2-butenyl ethyl 2-propynyl phosphate, 1,1-dimethyl-2-propynyl methyl 2-propenyl phosphate, 1,1-dimethyl-2-propynyl ethyl 2-propenyl phosphate, 2-butenyl 1,1-dimethyl-2-propynyl methyl phosphate, 2-butenyl ethyl 1,1-dimethyl-2-propynyl phosphate, etc. Of those, preferred are methyl 2-propenyl 2-propynyl phosphate and ethyl 2-propenyl 2-propynyl phosphate; and more preferred is ethyl 2-propenyl 2-propynyl phosphate. [0054] From the vievTpoint of improving the low-temperature and high-temperature cycle properties and improving the load characteristics after high-temperature charging storage, preferred are the compounds represented by the above-mentioned general formula (I) where X is a group -C(=0)-, a group -C(=0)-C{=0) - or a group -S{=0)2-, more preferably a group -C (=0) -C (=0) - or a group -S (=0) 2- even more preferably a group -S(=0)2-- Of those, preferred are 2-propenyl 3-butynoate, 2-propenyl 2-propynyl oxalate, 2-propynyl vinylsulfonate, 1,1-dimethyl-2-propynyl vinylsulfonate, vinyl 2-propyne-1-sulfonate, and2-propenyl 2-propyne-1-sulfonate; and more preferred are 2-propenyl 2-propynyl oxalate, 2-propynyl vinylsulfonate, and 2-propenyl 2-propyne-l-sulfonate; and even more preferred is 2-propynyl vinylsulfonate. [0055] In the nonaqueous electrolytic solution of the present invention, the content of at least one alkynyl compound represented by the general formula (I) is from 0.01 to 10% by mass of the nonaqueous electrolytic solution. When the content is more than 10% by mass, then a surface film may be formed excessively on an electrode to worsen low-temperature cycle properties; but when less than 0.01% by mass, then the surface film formation would be insufficient, therefore failing in attaining the effect of improving high-temperature cycle properties. The content is preferably at least 0.05% by mass in the nonaqueous electrolytic solution, more preferably at least 0 .1% by mass, even more preferably at least 0.3% by mass; and its upper limit is preferably at most 7% by mass, more preferably at most 5% by mass, even more preferably at most 3% by mass. Even when used alone, the compound represented by the general formula (I) can improve the low-temperature and high-temperature cycle properties and the load characteristics after high-temperature charging storage, but when combined with a nonaqueous solvent and an electrolyte salt to be mentioned below, the compound can exhibit a specific effect of synergistically improving the low-temperature and high-temperature cycle properties and the load characteristics after high-temperature charging storage. Though the reason is not clear, it may be considered that a mixture surface film having a high ionic conductivity and comprising the alkynyl compound represented by the general formula (I) and, as combined, those constitutive elements of the nonaqueous solvent and the electrolyte salt could be formed. [0056] (Alkynyl Sulfonate Compound Represented by General Formula(III)) [0057] [Chemical Formula 8] [0058] In the general formula (III), R' represents an linear or branched alkynyl group having from 3 to 8 carbon atoms; X* represents an alkylene group having from 1 to 8 carbon atoms, or a divalent linking group having from 2 to 8 carbon atoms and containing at least one ether bond; m indicates 0 or 1. When m is 0, R^ represents a formyl group, a linear or branched acyl group having from 2 to 8 carbon atoms, an arylcarbonyl group having from 7 to 15 carbon atoms, a linear or branched alkanesulfonyl group having from 1 to 8 carbon atoms, an linear or branched alkynyloxysulfonyl group having from 3 to 8 carbon atoms, an arylsulfonyl group having from 6 to 15 carbon atoms, a linear or branched dialkylphosphoryl group having from 2 to 16 carbon atoms, a linear or branched alkyl (alkoxy)phosphoryl group having from 2 to 16 carbon atoms, or a linear or branched dialkylphosphoryl group having from 2 to 16 carbon atoms. When m is 1, R^ represents a formyl group, a linear or branched alkyl group having from 1 to 8 carbon atoms, a linear or branched acyl group having from 2 to 8 carbon atoms, an arylcarbonyl group having from 7 to 15 carbon atoms, a linear or branched alkanesulfonyl group having from 1 to 8 carbon atoms, an arylsulfonyl group having from 6 to 15 carbon atoms, a linear or branched dialkylphosphoryl group having from 2 to 16 carbon atoms, a linear or branched alkyl(alkoxy)phosphoryl group having from 2 to 16 carbon atoms, or a linear or branched dialkoxyphosphoryl group having from 2 to 16 carbon atoms. At least one hydrogen atom on the carbon atom of R', X* and R^ may be substituted with a halogen atom. [0059] In the general formula (III) , the alkynyl group represented by R' is preferably a linear alkynyl group such as a 2-propynyl group, a 2-butynyl group, a 3-butynyl group, a 4-pentynyl group, a 5-hexynyl group, etc.; or a branched alkynyl group such as a 1-methyl-2-propynyl group, a 1-methyl-2-butynyl group, a 1,1-dimethyl-2-propynyl group, etc. Of those, the alkynyl group represented by R' is more preferably a 2-propynyl group, a 2-butynyl group, a 3-butynyl group, a 1-methyl-2-propynyl group or a 1,1-dimethyl-2-propynyl group, further preferably a 2-propynyl group, a 3-butynyl group or a 1,1-dimethyl-2-propynyl group, and most preferably a 2-propynyl group. [0060] In the general formula (III), the linear or branched alkylene group having from 1 to 8 carbon atoms of X includes an unsubstituted alkylene group such as a methylene group, an ethylene group, a triraethylene group, a tetramethylene group, a pentamethylene group, a hexamethylene group, etc.; and a substituted alkylene group such as an ethylidene group, a propane-1,2-diyl group, a propylidene group, an isopropylidene group, a butane-1,3-diyl group, a 2-methylpropane-l,2-diyl group, a butylidene group, etc. Of those, preferred is an alkylene group having from 1 to 4 carbon atoms, more preferred is an alkylene group having from 1 to 3 carbon atoms, even more preferred is an alkylene group having 2 or 3 carbon atoms, and especially preferred is an alkylene group having 2 carbon atoms. Concretely, preferred are an unsubstituted alkylene group such as a methylene group, an ethylene group, a trimethylene group, a tetramethylene group, a pentamethylene group, etc. ; and a substituted alkylene group such as an ethylidene group, a propane-1,2-diyl group, a propylidene group, an isopropylidene group, etc.; more preferred are a methylene group, an ethylene group, a trimethylene group, an ethylidene group, a propane-1,2-diyl group, a propylidene group, and an isopropylidene group; even more preferred are an ethylene group, an ethylidene group, and a trimethylene group; and especially preferred is an ethylene group. The divalent linking group having from 2 to 8 carbon atoms and containing at least one ether bond is preferably -CH2OCH2-, -C2H4OC2H4- or -C2H4OC2H4OC2H4-, more preferably -C2H4OC2H4- . The number of the ether bond is from 1 to 3, but is preferably 1, The carbon number of the two alkylene groups at both sides of the ether oxygen may be asymmetric or symmetric, but is preferably symmetric. The alkylene groups at both sides of the ether oxygen may be branched. [0061] In the general formula (III) , m is 0 or 1, but more preferably m is 1. When m is 0, R^ is more preferably a formyl group, a linear or branched acyl group having from 2 to 8 carbon atoms, an arylcarbonyl group having from 7 to 15 carbon atoms, a linear or branched alkanesulfonyl group having from 1 to 8 carbon atoms, an linear or branched alkynyloxysulfonyl group having from 3 to 8 carbon atoms, or an arylsulfonyl group having from 6 to 15 carbon atoms, even more preferably a linear or branched acyl group having from 2 to 8 carbon atoms, or a linear or branched alkynyloxysulfonyl group having from 3 to 8 carbon atoms, especially preferably a linear or branched alkynyloxysulfonyl group having from 3 to 8 carbon atoms. When m is 1, R is more preferably a formyl group, a linear or branched alkyl group having from 1 to 8 carbon atoms, a linear or branched acyl group having from 2 to 8 carbon atoms, an arylcarbonyl group having from 7 to 15 carbon atoms, a linear or branched alkanesulf onyl group having from 1 to 8 carbon atoms, or an arylsulfonyl group having from 6 to 15 carbon atoms, even more preferably a linear or branched acyl group having from 2 to 8 carbon atoms, or a linear or branched alkanesulfonyl group having from 1 to 8 carbon atoms. [0062] The linear acyl group having from 2 to 8 carbon atoms represented by R^ is preferably an acetyl group, a propionyl group, a butyryl group, an isobutyryl group, or a pivaloyl group, more preferably an acetyl group or a propionyl group, even more preferably an acetyl group. The arylcarbonyl group having from 7 to 15 carbon atoms represented by R^ is preferably a benzoyl group, a toluylcarbonyl group, or a naphthoyl group, more preferably a benzoyl group. [0063] The linear or branched alkanesulfonyl group having from 1 to 8 carbon atoms represented by R is preferably a linear alkanesulfonyl group such as a methanesulfonyl group, an ethanesulfonyl group, a propanesulfonyl group, a butanesulfonyl group, a pentanesulfonyl group, a hexanesulfonyl group, a heptanesulfonyl group, an octanesulfonyl group, etc.; a branched alkanesulfonyl group such as a 2-propanesulfonyl group, a 2-butanesulfonyl group, a t-butanesulfonyl group, etc.; or a haloalkanesulfonyl group such as a f luoromethanesulfonyl group, a trifluoromethanesulfonyl group, a trifluoroethanesulfonyl group, a pentafluoropropanesulfonyl group, etc. Of those, more preferred are a linear alkanesulfonyl group and a haloalkanesulfonyl group; even more preferred are a methanesulfonyl group, an ethanesulfonyl group, and a trifluoromethanesulfonyl group; and especially preferred is a methanesulfonyl group. [0064] The linear or branched alkynyloxysulfonyl group having from 3 to 8 carbon atoms represented by R^ is preferably a 2-propynyloxysulfonyl group, a 2-butynyloxysulfonyl group, a 3-butynyloxysulfonyl group, a 4-pentynyloxysulfonyl group, a 5-hexynyloxysulfonyl group, a l-methyl-2-propynyloxysulfonyl group, a 1-methyl-2-butynyloxysulfonyl group, or a 1,1-dimethylT2-propynyloxysulfonyl group, more preferably a 2-propynyloxysulfonyl group, or a 1-methyl-2-propynyloxysulfonyl group, even more preferably a 2-propynyloxysulfonyl group. The arylsulfonyl group having from 6 to 15 carbon atoms represented by R^ is preferably a benzenesulfonyl group, a toluenesulfonyl group, a 1-naphthalenesulfonyl group, or a 2-naphthalenesulfonyl group, more preferably a benzenesulfonyl group or a toluenesulfonyl group. The linear or branched dialkylphosphonyl group having from 2 to 16 carbon atoms represented by R^ is preferably a dimethylphosphonyl group, a diethylphosphonyl group, a dipropylphosphonyl group, or a dibutylphosphonyl group, more preferably a dimethylphosphonyl group or a diethylphosphonyl group. [0065] The linear or branched alkyl (alkoxy)phosphoryl group having from 2 to 16 carbon atoms represented by R^ is preferably a methyl(methoxy)phosphoryl group, an ethyl (ethoxy) phosphoryl group, a propyl (propyloxy) phosphoryl group, or a butyl(butoxy)phosphoryl group, more preferably a methyl (methoxy) phosphoryl group or an ethyl(ethoxy)phosphoryl group. The linear or branched dialkoxyphosphoryl group having from 2 to 16 carbon atoms represented by R^ is preferably a dimethoxyphosphoryl group, a diethoxyphosphoryl group, a dipropoxyphosphoryl group, or a dibutoxyphosphoryl group, more preferably a dimethoxyphosphoryl group or a diethoxyphosphoryl group. In case where the substituents R, R and X are the above-mentioned preferred substituents, the embodiment is preferred since the low-temperature and high-temperature cycle properties and the load characteristics after high-temperature charging storage are markedly improved. [0066] The following are preferred examples of the alkynyl sulfonate compound represented by the above-mentioned general formula (III) where R' is a 2-propynyl group. (A-1) As the case where m is 0 and R^ is a formyl group, preferably mentioned are 2-propynyl 2-oxoethanesulfonate, 2-propynyl 3-oxopropanesulfonate, 2-propynyl 4-oxobutanesulfonate, 2-propynyl 5-oxopentanesulfonate, 2-propynyl 6-oxohexanesulfonate, 2-propynyl 7-oxoheptanesulfonate, 2-propynyl 3 -oxopropoxymethanesulfonate, etc. (A-2) As the case where m is 0 and R is an acyl group, preferably mentioned are 2-propynyl 2-oxopropanesulfonate, 2-propynyl 3-oxobutanesulfonate, 2-propynyl 4-oxopentanesulfonate, 2-propynyl 5-oxohexanesulfonate, 2-propynyl 6-oxoheptanesulfonate, 2-propynyl 7-oxooctanesulfonate, 2-propynyl 2-oxobutanesulfonate, 2-propynyl 3-oxopentanesulfonate, 2-propynyl 4-oxohexanesulfonate, 2-propynyl 5-oxoheptanesulfonate, 2-propynyl 6-oxooctanesulfonate, 2-propynyl 7-oxononanesulfonate, 2-propynyl 2-(3-oxobutoxy)ethanesulfonate, etc. [0067] (A-3) As the case where m is 0 and R is a sulfonyl group, preferably mentioned are the following compounds (A-3-1) , (A-3-2), (A-3-3), (A-3-4), (A-3-5), etc. (A-3-1) : 2-Propynyl methanesulfonylmethanesulfonate, 2-propynyl 2-(methanesulfonyl)ethanesulfonate, 2-propynyl 3-(methanesulfonyl)propanesulfonate, 2-propynyl 4-(methanesulfonyl)butanesulfonate, 2-propynyl 5-(methanesulfonyl)pentanesulfonate, 2-propynyl 6-(methanesulfonyl)hexanesulfonate, 2-propynyl ethanesulfonylmethanesulfonate, 2-propynyl 2-(ethanesulfonyl)ethanesulfonate, 2-propynyl 3-(ethanesulfonyl)propanesulfonate, 2-propynyl 4-(ethanesulfonyl)butanesulfonate, 2-propynyl 5-(ethanesulfonyl)pentanesulfonate, 6-(ethanesulfonyl)hexanesulfonate, trifluoromethanesulfonylmethanesulfonate, 2-(trifluoromethanesulfonyl)ethanesulfonate, 3-(trifluoromethanesulfonyl)propanesulfonate, 4-(trifluoromethanesulfonyl)butanesulfonate, 5(trifluoromethanesulfonyl)pentanesulfonate, 6-(trifluoromethanesulfonyl)hexanesulfonate, 2-(2(methanesulfonyl)ethoxy)ethanesulfonate. [0068] (A-3-2): 2-propynyl benzenesulfonylmethanesulfonate, 2-propynyl 2-(benzenesulfonyl)ethanesulfonate, 2-propynyl2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 3-4-5-6-benzenesulfonyl)propanesulfonate, benzenesulfonyl)butanesulfonate, benzenesulfonyl)pentanesulfonate, benzenesulfonyl)hexanesulfonate,2-3-4-5-6- 4-methylbenzenesulfonylmethanesulfonate,4-methylbenzenesulfonyl)ethanesulfonate, 4 -methylbenzenesulfonyl)propanesulfonate, 4-methylbenzenesulfonyl)butanesulfonate, 4-methylbenzenesulfonyl)pentanesulfonate, 4-methylbenzenesulfonyl)hexanesulfonate. 2-3-4-5-4-fluorobenzenesulfonylmethanesulfonate,4-fluorobenzenesulfonyl)ethanesulfonate, 4-fluorobenzenesulfonyl)propanesulfonate, 4-fluorobenzenesulfonyl)butanesulfonate, 4-fluorobenzenesulfonyl)pentanesulfonate. 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 6-(4-fluorobenzenesulfonyDhexanesulfonate, 2-propynyl 2-{2-benzenesulfonylethoxy)ethanesulfonate. [0069] 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl (A-3-3) : 2-Propynyl methoxysulfonylmethanesulfonate, 2-propynyl 2-(methoxysulfonyl)ethanesulfonate, 2-propynyl3 -(methoxysulfonyl)propanesulfonate,4-(methoxysulfonyl)butanesulfonate, 5-(methoxysulfonyl)pentanesulfonate,6-(methoxysulfonyl)hexanesulfonate, ethoxysulfonylmethanesulfonate,2-(ethoxysulfonyl)ethanesulfonate, 3-(ethoxysulfonyl)propanesulfonate,4-(ethoxysulfonyl)butanesulfonate, 5-(ethoxysulfonyl)pentane sulfonate,6-(ethoxysulfonyl)hexanesulfonate, 2-(2-(methoxysulfonyl)ethoxy)ethanesulfonate.2-Propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl [0070] (A-3-4): 2-propenyloxysulfonylmethanesulfonate, 2-(2-propenyloxysulfonyl)ethanesulfonate, 3-(2-(propenyloxysulfonyl)propanesulfonate, 4-(2-propenyloxysulfonyl)butanesulfonate, 5-(2-propenyloxysulfonyl)pentanesulfonate, 6-(2-propenyloxysulfonyl)hexanesulfonate, 2-(2 -(2-propenyloxysulfonyl)ethoxy)ethanesulfonate. (A-3-5): Di(2-propynyl) methane-1,1-disulfonate, di(2-propynyl) ethane-1,2-disulfonate, di(2-propynyl) di(2-propynyl) di(2-propynyl) di(2-propynyl) di(2-propynyl) propane-1,3-disulfonate, butane-1,4-disulfonate, pentane-1,5-di sulfonate, hexane-1,6-di sulfonate, 2,2'-oxydiethanesulfonate. [0071] 2-Propynyl 2-propynyl (A-4) As the case where m is 0 and R^ is a phosphoryl group, preferably mentioned are the following compounds (A-4-1), (A-4-2), (A-4-3), etc. 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl(A-4-1) dimethoxyphosphorylmethanesulfonate, 2 -(dimethoxyphosphoryl)ethanesulfonate, 2-prop ynyl 3-(dimethoxyphosphoryl)propanesulfonate, 2-propynyl 4-(dimethoxyphosphoryl)butanesulfonate, 5-(dimethoxyphosphoryl)pentanesulfonate, 6 - (d—dimethoxyphosphoryl) hexanesulfonate, diethoxyphosphorylmethanesulfonate, 2-(diethoxyphosphoryl)ethanesulfonate,3-(diethoxyphosphoryl)propanesulfonate, 4-(diethoxyphosphoryl)butanesulfonate, 5-(diethoxyphosphoryl)pentanesulfonate, 6-(diethoxyphosphoryl)hexanesulfonate, 2-(2-(dimethoxyphosphoryl)ethoxy)ethanesulfonate. (A-4-2): 2-Propynylmethoxy(methyl)phosphorylmethanesulfonate, 2-propynyl 2-(methoxy(methyl)phosphoryl)ethanesulfonate, 2-propynyl 3-(methoxy(methyl)phosphoryl)propanesulfonate, 2-propynyl 4-(methoxy(methyl)phosphoryl)butanesulfonate, 2-propynyl 5-(methoxy(methyl)phosphoryl)pentanesulfonate, 2-propynyl 6-(methoxy(methyl)phosphoryl)hexanesulfonate, 2-propynyl 2-(2-methoxy(methyl)phosphoryl)ethoxy)ethanesulfonate, 2-propynyl ethoxy(methyl)phosphorylmethanesulfonate, 2-propynyl 2 -(ethoxy(methyl)phosphoryl)ethanesulfonate, 2-propynyl 3-(ethoxy(methyl)phosphoryl)propanesulfonate, 2-propynyl ethyl(methoxy)phosphorylmethanesulfonate, 2-propynyl 2 -(ethyl(methoxy)phosphoryl)ethanesulfonate, 2-propynyl 3-(ethyl(methoxy)phosphoryl)propanesulfonate. (A-4-3): 2-Propynyl dimethylphosphorylmethanesulfonate, 2-propynyl 2-(dimethylphosphoryl)ethanesulfonate, 2-propynyl 3-(dimethylphosphoryl)propanesulfonate, 2-propynyl 4-(dimethylphosphoryl)butanesulfonate, 2-propynyl 5-(dimethylphosphoryl)pentanesulfonate, 2-propynyl 6-(dimethylphosphoryl)hexanesulfonate, 2-propynyl 2-(2-(dimethylphosphoryl)ethoxy)ethanesulfonate. [0072] (B-1) As the case where m is 1 and R is an alkyl group, preferably mentioned are 2-propynyl methoxymethanesulfonate, 2-propynyl 2-methoxyethanesulfonate, 2-propynyl 3-methoxypropanesulfonate, 2-propynyl 4-methoxybutanesulfonate, 2-propynyl 5-methoxypentanesulfonate, 2-propynyl 6-methoxyhexanesulfonate, 2-propynyl ethoxymethanesulfonate, 2-propynyl 2-ethoxyethanesulfonate, 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 3-ethoxypropanesulfonate, 4-ethoxybutanesulfonate, 5-ethoxypentanesulfonate, 6-ethoxyhexanesulfonate, 2-{2-methoxyethoxy)ethanesulfonate, etc. [0073] 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl Are (B-2) As the case where m is 1 and R^ is a formyl group, preferably mentioned formyloxymethanesulfonate, 2-(formyloxy)ethanesulfonate, 3-{formyloxy)propanesulfonate, 4-(formyloxy)butanesulfonate, 5-(formyloxy)pentanesulfonate, 6-(formyloxy)hexanesulfonate, 2-(2 -(formyloxy)ethoxy)ethanesulfonate, etc. [0074] (B-3) As the case where m is 1 and R is an acyl group, preferably mentioned are 2-propynyl acetyloxymethanesulfonate, 2-propynyl 2-(acetyloxy)ethanesulfonate, 2-propynyl 3-(acetyloxy)propanesulfonate, 2-propynyl 4-(acetyloxy)butanesulfonate, 2-propynyl 5-(acetyloxy) pentanesulfonate, 2-propynyl 6-(acetyloxy)hexanesulfonate, 2-propynyl propionyloxymethanesulfonate, 2-propynyl 2-(propionyloxy)ethanesulfonate, 2-propynyl 3 - (propionyloxy) propanesulf onate, 2 –propynyl 2-propynyl 2-propynyl 2-propynyl 4-(propionyloxy)butanesulfonate, 5-(propionyloxy)pentanesulfonate, 6-(propionyloxy)hexanesulfonate, 2-(2-(acetyloxy)ethoxy)ethanesulfonate, etc, [0075] 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl (B-4) As the case where m is 1 and R^ is a sulfonyl group. preferably mentioned are methanesulfonyloxymethanesulfonate, 2-(methanesulfonyloxy)ethanesulfonate,3 -(methanesulfonyloxy)propanesulfonate, 4-(methanesulfonyloxy)butanesulfonate,5-(methanesulfonyloxy)pentanesulfonate, 6-(methanesulfonyloxy)hexanesulfonate,ethanesulfonyloxymethanesulfonate, 2 -(ethanesulfonyloxy)ethanesulfonate, 3-(ethanesulfonyloxy)propanesulfonate, 4 -(ethanesulfonyloxy)butanesulfonate,5-(ethanesulfonyloxy)pentanesulfonate, 5-(ethanesulfonyloxy)hexanesulfonate,trifluoromethanesulfonyloxymethanesulfonate, 2-(trifluoromethanesulfonyloxy)ethanesulfonate, 2-propynyl 3-(tri fluoromethanesulfonyloxy)propanesulfonate, 2-propynyl 4-(trifluoromethanesulfonyloxy)butanesulfonate, 2-propynyl 5-(trifluoromethanesulfonyloxy)pentanesulfonate, 2-propynyl 6-(trifluoromethanesulfonyloxy)hexanesulfonate, 2-propynyl 2 -(2 -(methanesulfonyloxy)ethoxy)ethanesulfonate, etc. [0076] 2-Propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl (B-5) As the case where m is 1 and R is a phosphoryl group, preferably mentioned are the following compounds (B-5-1), (B-5-2), (B-5-3), etc. (B-5-1) dimethoxyphosphoryloxymethanesulfonate, 2-(dimethoxyphosphoryloxy)ethanesulfonate, 3-(dimethoxyphosphoryloxy)propanesulfonate, 4-(dimethoxyphosphoryloxy)butanesulfonate, 5-(dimethoxyphosphoryloxy)pentanesulfonate, 6-(dimethoxyphosphoryloxy)hexanesulfonate, diethoxyphosphoryloxymethanesulfonate, 2-(diethoxyphosphoryloxy)ethanesulfonate, 3 -(diethoxyphosphoryloxy)propanesulfonate, 4-(diethoxyphosphoryloxy)butanesulfonate, 5-(diethoxyphosphoryloxy)pentanesulfonate, 6-(diethoxyphosphoryloxy)hexanesulfonate, 2-(2-(dimethoxyphosphoryloxy)ethoxy)ethanesulfonate. [0077] (B-5-2) 2-Propynyl methoxy(methyl)phosphoryloxymethanesulfonate, 2-propynyl 2-(methoxy)methyl)phosphoryloxy)ethanesulfonate, 2-propynyl 3-(methoxy(methyl)phosphoryloxy)propanesulfonate, 2-propynyl 4-(methoxy(methyl)phosphoryloxy)butanesulfonate, 2-propynyl 5-(methoxy(methyl)phosphoryloxy)pentanesulfonate, 2 -propynyl 6 - (methoxy (methyl) phosphoryloxy) hexanesul fonate, 2-propynyl 2-(2-(methoxy(methyl)phosphoryloxy)ethoxy)ethanesulfonate, 2-propynyl ethoxy(methyl)phosphoryloxymethanesulfonate, 2 -propynyl 2 - (ethoxy (methyl) phosphoryloxy) ethanesulf onate, 2-propynyl 3 - (ethoxy (methyl) phosphoryloxy) propanesul f onate, 2-propynyl ethyl(methoxy)phosphoryloxymethanesulfonate, 2-propynyl 2 - (ethyl (methoxy) phosphoryloxy) ethanesulf onate, 2-propynyl 3 -(ethyl(methoxy) phosphoryloxy)propanesulfonate. (B-5-3) 2-Propynyl dimethylphosphoryloxymethanesulf onate, 2 -propynyl 2 -(dimethylphosphoryloxy)ethanesulfonate, 2-propynyl 3-(dimethylphosphoryloxy)propanesulfonate, 2-propynyl 4-(dimethylphosphoryloxy)butanesulfonate, 2-propynyl 5- (dimethylphosphoryloxy) pentanesul fonate, 2 –propynyl 6- (dimethylphosphoryloxy) hexanesul f onate, 2 -propynyl 2-(2-(dimethylphosphoryloxy)ethoxy)ethanesulfonate. [0078] From the viewpoint of improving the load characteristics after high-temperature charging storage, the following are preferred from among the alkynyl sulfonate compounds represented by the general formula (III) . (A-1) : 2-pPropynyl 2-oxoethanesulfonate, 2-propynyl 3-oxopropanesulfonate, 2-propynyl 4-oxobutanesulfonate; (A-2): 2-propynyl 2-oxopropanesulfonate, 2-propynyl 3-oxobutanesulfonate, 2-propynyl 4-oxopentanesulfonate, 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl (A-3-5): di (2-propynyl) di (2-propynyl) di (2-propynyl) 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-propynyl .2-propynyl 5-oxohexanesulfonate; (A-3-1):methanesulfonylmethanesulfonate, 2-(methanesulfonyl)ethanesulfonate,3-(methanesulfonyl)propanesulfonate; (A-3-3) methoxysulfonylmethanesulfonate,2-(methoxysulfonyl)ethanesulfonate, 3 -(methoxysulfonyl)propanesulfonate; (A-3 -4)2-propenyloxysulfonylmethanesulfonate, 2-(2-propenyloxysulfonyl)ethanesulfonate,3 -(2-propenyloxysulfonyl)propanesulfonate; di(2-propynyl) methane-1,1-disulfonate,ethane-1,2-disulfonate,propane-1,3-disulfonate, 2,2'-oxydiethanesulfonate; (B-1):methoxymethanesulfonate, 2-methoxyethanesulfonate,3-methoxypropanesulfonate; (B-2): formyloxymethanesulfonate,2-(formyloxy)ethanesulfonate,3-(formyloxy)propanesulfonate; (B-3):acetyloxymethanesulfonate, 2- (acetyloxy)ethanesulfonate,3-(acetyloxy)propanesulfonate; (B-4): methanesulfonyloxymethanesulfonate,2-(methanesulfonyloxy)ethanesulfonate, 3-(methanesulfonyloxy)propanesulfonate; (B-5) 2-propynyl dimethoxyphosphoryloxymethanesulfonate, 2-propynyl 2-(dimethoxyphosphoryloxy)ethanesulfonate, 2-propynyl 3 -(dimethoxyphosphoryloxy)propanesulfonate. [0079] Of the alkynyl sulfonate compounds represented by the general formula (III) , more preferred are (A-3-5) di(2-propynyl) ethane-1,2-disulfonate, di(2-propynyl) propane-1,3-disulfonate,2,2'-oxydiethanesulfonate; 2-methoxyethanesulfonate, 3-methoxypropanesulfonate; 2-(formyloxy)ethanesulfonate, 3(formyloxy)propanesulfonate; 2-(acetyloxy)ethanesulfonate.3-(acetyloxy)propanesulfonate;2-(methanesulfonyloxy)ethanesulfonate,3-(methanesulfonyloxy)propanesulfonate; and even morepreferred are (A-3-5) di{2-propynyl) ethane-1,2-disulfonate,di(2-propynyl) propane-1,3-disulfonate; (B-l) 2-propynyl2-propynyl 2-propynyl 2-propynyl 2-propynyl 2-methoxyethanesulfonate; (B-3)2-(acetyloxy)ethanesulfonate,3-(acetyloxy)propanesulfonate; (B-4)2-(methanesulfonyloxy)ethanesulfonate, 3- (methanesulfonyloxy)propanesulfonate. [0080] In the nonaqueous electrolytic solution of the present invention, the content of at least one alkynyl sulfonate compound represented by the general formula (III) is from 0.01 to 10% by mass of the nonaqueous electrolytic solution. When the content is more than 10% by mass, then a surface film may be formed excessively on an electrode to worsen low-temperature and high-temperature cycle properties and load characteristics after high-temperature charging storage; but when less than 0.01% by mass, then the surface film formation would be insufficient, therefore failing in attaining the effect of improving low-temperature and high-temperature cycle properties and load characteristics after high-temperature charging storage. The content is preferably at least 0 .1% by mass in the nonaqueous electrolytic solution, more preferably at least 0.5% by mass, even more preferably at least 1% by mass; and its upper limit is preferably at most 7% by mass, more preferably at most 5% by mass, even more preferably at most 3% by mass. Even when used alone, the alkynyl sulfonate compound represented by the general formula (III) can improve the low-temperature and high-temperature cycle properties and the load characteristics after high-temperature charging storage, but when combined with a nonaqueous solvent, an electrolyte salt and other additives to be mentioned below, the compound can exhibit a specific effect of synergistically improving the low-temperature and high-temperature cycle properties and the load characteristics after high-temperature charging storage. Though the reason is not clear, it may be considered that a mixture surface film having a high ionic conductivity and comprising the alkynyl sulfonate compound represented by the general formula (III) and, as combined, those constitutive elements of the nonaqueous solvent, the electrolyte salt and the other additives could be formed. [0081] [Nonaqueous Solvent] The nonaqueous solvent for use in the nonaqueous electrolytic solution of the present invention includes cyclic carbonates, linear carbonates, linear esters, lactones, ethers, amides, phosphates, sulfones, nitriles, S=0 bond-containing compounds (excluding alkynyl sulfonate compounds represented by the general formula (III)), etc. (Cyclic Carbonates) The cyclic carbonates include ethylene carbonate (EC) , propylene carbonate (PC), butylene carbonate (BC) , 4-fluoro-l,3-dioxolan-2-one (FEC), trans or cis-4,5-difluoro-l,3-dioxolan-2-one (hereinafter the two are collectively called "DFEC"), vinylene carbonate (VC), vinylethylene carbonate (VEC), etc. Of those, preferred is use of at least one cyclic carbonate having a carbon-carbon double bond or a fluorine atom, as markedly enhancing the effect of improving high-temperature cycle properties and load characteristics after high-temperature charging storage; and more preferred is use of both a cyclic carbonate having a carbon-carbon double bond and a cyclic carbonate having a fluorine atom. As the cyclic carbonate having a carbon-carbon double bond, more preferred are VC and VEC; and as the cyclic carbonate having a fluorine atom, more preferred are FEC and DFEC. The content of the fluorine atom-containing cyclic carbonate is preferably at least 0.07% by volume relative to the total volume of the nonaqueous solvent, more preferably at least 4% by volume, even more preferably at least 7% by volume, from the viewpoint of improving the low-temperature and high-temperature cycle properties and the load characteristics after high-temperature charging storage; and the upper limit thereof is preferably at most 35% by volume, more preferably at most 25% by volume, even more preferably at most 15% by volume. Also from the same viewpoint as above, the solvent preferably contain PC. The PC content is preferably at least 0 . 03% by volume relative to the total volume of the nonaqueous solvent, more preferably at least 1% by volume, even more preferably at least 3% by volume; and the upper limit thereof is preferably at most 25% by volume, more preferably at most 15% by volume, even more preferably at most 10% by volume. [0082] One kind of those solvents may be used, but using two or more different kinds as combined is preferred as further enhancing the effect of improving the above-mentioned battery performance. Even more preferably, three or more different kinds are combined. Preferred combinations of the cyclic carbonates include EC and VC; PC and VC; FEC and VC; FEC and EC; FEC and PC; DFEC and EC; DFEC and PC; DFEC and VC; DFEC and VEC; EC and PC and VC; EC and FEC and VC; EC and VC and VEC; FEC and PC and VC; DFEC and PC and VC; DFEC and EC and VC; FEC and EC and PC and VC; DFEC and EC and PC and VC, etc. Of those combinations, more preferred combinations are EC and VC; FEC and EC; DFEC and PC; FEC and EC and PC; EC and FEC and VC; EC and VC and VEC; FEC and PC and VC; FEC and EC and PC and VC. Not specifically defined, the content of the cyclic carbonate is preferably within a range of from 10 to 40% by volume relative to the total volume of the nonaqueous solvent. When the content is less than 10% by volume, then the electric conductivity of the nonaqueous electrolytic solution may lower, and the low-temperature and high-temperature cycle properties may worsen; but when more than 40% by volume, then the low-temperature and high-temperature cycle properties and the load characteristics after high-temperature charging storage may worsen since the viscosity of the nonaqueous electrolytic solution may incerase. Consequently, the content preferably falls within the above-mentioned range. [0083] The linear carbonates include asymmetric linear carbonates such as methyl ethyl carbonate (MEC) , methyl propyl carbonate, methyl isopropyl carbonate, methyl butyl carbonate, ethyl propyl carbonate, etc. ; symmetric linear carbonates such as dimethyl carbonate (DMC) , diethyl carbonate (DEC) , dipropyl carbonate, dibutyl carbonate, etc. From the viewpoint of improving the low-temperature cycle properties and improving the load characteristics after high-temperature charging storage, the solvent preferably contains a methyl group-having linear carbonate, more preferably DMC. From the viewpoint of improving the high-temperature cycle properties and improving the load characteristics after high-temperature charging storage, the solvent preferably contains an asymmetric carbonate, more preferably MEC. Not specifically defined, the content of the linear carbonate is preferably within a range of from 60 to 90% by volume relative to the total volume of the nonaqueous solvent. When the content is less than 60% by volume, then the viscosity of the nonaqueous electrolytic solution may increase and the low-temperature cycle properties and the load characteristics after high-temperature charging storage may worsen. On the other hand, when the content is more than 90% by volume, then the electric conductivity of the nonaqueous electrolytic solution may lower, and the above-mentioned battery performance may thereby worsen. Consequently, the content preferably falls within the above-mentioned range. [0084] The linear esters include methyl propionate, ethyl propionate, methyl acetate, ethyl acetate, methyl pivalate, butyl pivalate, hexyl pivalate, octyl pivalate, dimethyl oxalate, ethyl methyl oxalate, diethyl oxalate, etc. The lactones include y-butyrolactone, y-valerolactone, a-angelicalactone, etc. ,- the ethers include cyclic ethers such as tetrahydrofuran, 2-methyltetrahydrofuran, 1,3-dioxolane, 1,3-dioxane, 1,4-dioxane, etc.; and linear ethers such as 1,2-dimethoxyethane, 1,2-diethoxyethane, 1,2-dibutoxyethane, etc. The amides include dimethylformamide, etc.; the phosphates include trimethyl phosphate, tributyl phosphate, trioctyl phosphate, etc.; the sulfones include sulfolane, etc.; the nitriles include acetonitrile, propionitrile, succinonitrile, glutaronitrile, adiponitrile, pimelonitrile, etc. [0085] The S=0 bond-containing compounds include sultone compounds such as 1,3-propanesultone, 1,3-butanesultone, 1,4-butanesultone, etc.; cyclic sulfite compounds such as ethylene sulfite, hexahydrobenzo[1,3,2]dioxathiol-2-oxide (also referred to as 1,2-cyclohexanediol cyclic sulfite), 5-vinyl-hexahydro-l,3,2-benzodioxathiol-2-oxide, etc. ; sulfonic acid ester compounds such as 1,2-ethanediol dimethanesulfonate, 1,2-propanediol dimethanesulfonate, 1,3-propanediol dimethanesulfonate, 1,4-butanediol dimethanesulfonate, 1,5-pentanediol dimethanesulfonate, 2-propynyl methanesulfonate, methylenemethane disulfonate, etc.; and vinyl sulfone compounds such as divinyl sulfone, 1,2-bis(vinylsulfonyl)ethane, bis(2-vinylsulfonylethyl) ether, etc. [0086] As other nonaqueous solvents, preferably used here are linear carboxylic acid anhydrides such as acetic anhydride, propionic anhydride, etc.; cyclic acid anhydrides such as succinic anhydride, maleic anhydride, glutaric anhydride, itaconic anhydride, 3-sulfo-propionic anhydride, etc.; cyclic phosphazene compounds such as methoxypentafluorocyclotriphosphazene, ethoxypentafluorocyclotriphosphazene, phenoxypenta f luorocyc 1 ot r iphospha zene, ethoxyheptafluorocyclotetraphosphazene, etc. ; branchedalkyl group-having aromatic compounds such as cyclohexylbenzene, fluorocyclohexylbenzene compounds (including 1-fluoro-2-cyclohexylbenzene, 1-fluoro-3 -cyclohexylbenzene, and 1-fluoro-4-cyclohexylbenzene), tert-butylbenzene, tert-amylbenzene, l-fluoro-4-tert-butylbenzene, etc.; and other aromatic compounds such as biphenyl, terphenyls (o-, m-, andp-form), diphenyl ether, fluorobenzene, difluorobenzenes (o-, m-, andp-form), anisole, 2,4-difluoroanisole, partially hydrogenated terphenyls (including 1,2-dicyclohexylbenzene, 2-phenylbicyclohexyl, 1,2-diphenylcyclohexane, and o-cyclohexylbiphenyl), etc. [0087] In general, the above-mentioned nonaqueous solvents are combined and used as a mixture thereof for attaining suitable physical properties. The combination includes, for example, a combination of a cyclic carbonate and a linear carbonate, a combination of a cyclic carbonate, a linear carbonate and a lactone, a combination of a cyclic carbonate, a linear carbonate and an ether, a combination of a cyclic carbonate, a linear carbonate and a linear ester, a combination of a cyclic carbonate, a linear carbonate and a nitrile, a combination of a cyclic carbonate, a linear carbonate and an S=0 bond-containing compound, etc. Of those, preferred is use of a nonaqueous solvent of a combination of at least a cyclic carbonate and a linear carbonate, as improving the low-temperature and high-temperature cycle properties and the load characteristics after high-temperature charging storage. In this, the proportion of the cyclic carbonate and the linear carbonate is not specifically defined, but preferably, the ratio (by volume) of cyclic carbonate/linear carbonate is from 10/90 to 40/60, more preferably from 15/85 to 35/65, even more preferably from 20/80 to 30/70. [0088] [Electrolyte Salt] The electrolyte salt for use in the present invention includes lithium salts such as LiPFg, LiPOzFa, LiBF4, LiCl04, etc.; linear fluoroalkyl group-having lithium salts such as LiN(S02CF3)2, LiN(S02C2F5)2, LiCFaSOa, LiC (SO2CF3) 3 , LiPF4(CF3)2, LiPF3(C2F5)3, LiPF3(CF3)3, LiPF3(iSO-C3F7)3, LiPF5{iSO-C3F7) , etc.; cyclic fluoroalkylene chain-having lithium salts such as (CF2)2(S02)2NLi, (CF2) 3 (SO2) 2NLi, etc.; and lithium salts with an oxalate complex as the anion therein, such as lithium bis[oxalate-0,0']borate, lithium difluoro[oxalate-0,0']borate, etc. Of those, especially preferred electrolyte salts are LiPFg, LiBF4, LiN(S02CF3)2 and LiN(S02C2F5) 2. One alone or two or more of those electrolyte salts may be used here either singly or as combined. [0089] A preferred combination of these electrolyte salts comprises LiPFe and contains at least one selected from LiBF4, LiN(S02CF3)2 and LiN(S02C2F5)2. Preferred are a combination of LiPFs and LiBF4, a combination of LiPFg and LiN(S02CF3) 2, a combination of LiPFe and LiN{S02C2F5)2, etc. Regarding the ratio (by mol) of LiPFg/[LiBF4 or LiN(S02CF3)2 or LiN(S02C2F5)2] , when the ratio of LiPFg is lower than 70/3 0 and when the ratio of LiPFg is higher than 99/1, then the low-temperature and high-temperature cycle properties and the load characteristics after high-temperature charging storage may worsen. Accordingly, the ratio (by mol) of LiPFg/[LiBF4 or LiN(S02CF3)2 or LiN(S02C2F5)2] is preferably within a range of from 70/30 to 99/1, more preferably within a range of from 80/20 to 98/2. When the electrolyte salts are used as the combination thereof falling within the above-mentioned range, then the battery characteristics of the low-temperature and high-temperature cycle properties and the load characteristics after high-temperature charging storage and others can be further improved. The concentration of all these electrolyte salts as dissolved in the solution is generally preferably at least 0.3 M relative to the above-mentioned nonaqueous solvent, more preferably at least 0.5 M, even more preferably at least 0.7 M, and further preferably at least 1.0 M. The upper limit of the concentration is preferably at most 2.5 M, more preferably at most 2.0 M, even more preferably at most 1.5 M. [0090] As the electrolyte for electric double layer capacitors (condensers) , usable are known quaternary ammonium salts such as tetraethylammonium tetrafluoroborate, triethylmethylammonium tetrafluoroborate, tetraethylammonium hexafluorophosphate, etc. [0091] [Production of Nonaqueous Electrolytic Solution] The nonaqueous electrolytic solution of the present invention can be prepared, for example, by: mixing the nonaqueous solvents; adding the electrolyte salt to the mixture; and adding thereto at least one alkynyl compound represented by the general formula (I) in an amount of from 0.01 to 10% by mass relative to the mass of the nonaqueous electrolytic solution. In this case, the nonaqueous solvent to be used, and the compound to be added to the electrolytic solution are preferably previously purified within a range not significantly detracting from the producibility, in which, therefore, the impurity content is preferably as low as possible. [0092] [Electrochemical Element] The electrochemical element of the present invention comprises a positive electrode, a negative electrode, and a nonaqueous electrolytic solution of an electrolyte salt dissolved in a nonaqueous solvent, and is characterized in that the nonaqueous electrolytic solution is the above-mentioned nonaqueous electrolytic solution of the present invention. The electrochemical element includes the following first to fourth electrochemical elements. As the nonaqueous electrolyte, not only a liquid one but also a gelled one can be used. Further, the nonaqueous electrolytic solution of the present invention can also be used for solid polymer electrolytes. Above all, the solution is preferably used for the first electrochemical element using a lithium salt as the electrolyte salt (that is, for lithium batteries) or for the fourth electrochemical element (that is, for lithium ion capacitors), more preferably for lithium batteries, and most preferably for lithium secondary batteries. [0093] [The First Electrochemical Element (lithium battery)] The lithium battery of the present invention collectively means a lithium primary battery and a lithium secondary battery. The lithium battery of the present invention comprises a positive electrode, a negative electrode and the nonaqueous electrolytic solution of an electrolyte salt dissolved in a nonaqueous solvent. In this, the other constitutive components such as the positive electrode and the negative electrode than the nonaqueous electrolytic solution can be used with no particular limitation thereon. (Lithium Secondary Battery) As the positive electrode active material for the lithium secondary battery, usable is a complex metal oxide with lithium that contains at least one selected from cobalt, manganese and nickel. One kind of these positive electrode active materials can be used alone, or two or more kinds of them can be used in combination. The lithium complex metal oxide includes, for example, LiCoOa, LiMn204, LiNi02, LiCOi.xNix02 (0.01