LITHIUM SECONDARY BATTERY Technical Field [00011 The present invention relates to a lithium secondary battery. Background Art [00021 A lithium secondary battery is characterized in that it is small and has a large capacity, and has been widely used as a power source for electronic device such as cellular phone and notebook computer, and has contributed to the improvement in the convenience of portable IT devices. In recent years, attention is also focused on the use of a lithium secondary battery for applications where the battery is larger, including a power source to drive a two-wheeled vehicle, an automobile, or the like, and a storage battery for smart grid. I00031 For a lithium secondary battery, high safety in a wide range of temperature conditions is required in addition to further improvement in energy density and lifetime property wherein the battery can endure long term use. Accordingly, studies have been widely conducted on various materials and additives with respect t o the composition of the electrolyte solution, which has a great influence on the long-term cycle and the safety. [00041 In general, a carbonate-based non-aqueous solvent is used for an electrolyte solution in a lithium secondary battery. That is because the carbonate-based solvent has excellent electrochemical resistance and is inexpensive in terms of cost. As an electrolyte solution of a carbonate-based solvent, a mixed electrolyte solution containing a cyclic carbonate such as ethylene carbonate (EC) and propylene carbonate (PC) and a chain carbonate such as diethyl carbonate (DEC) and dimethyl carbonate (DMC) is usually used. The cyclic carbonate has a high dielectric constant, and therefore has a function of dissolvingldissociating a lithium salt such as LiPFe. The chain carbonate has a low viscosity, and therefore has a function of improving the diffusibility of lithium ion in the electrolyte solution. roo051 Because the carbonate-based solvents have low flash points and high combustibility, however, there is a risk of ignitionlexplosion caused by overcharge or overheating. The danger is greater in the case of ignition or explosion as the battery is larger, and therefore the improvement in safety is an important problem for a large-sized battery, in particular. In addition, during long-term cycle or under high-temperature conditions, the decomposition of the solvent of the electrolyte solution, as well as the deterioration of electrodes, may occur, resulting in the reduction in the capacity, the generation of gas, and the like. The problems tend to be recognized markedly in a lithium secondary battery comprising a positive electrode for high voltage which comprises a spinel compound such as LiNi0.5Mn1.604 as a positive electrode active material, in particular, the battery attracting attention as to higher energy density in recent years. [00061 As a method for solving the problems, Patent Literatures 1 to 2 disclose that an electrolyte solution containing a solvent which contains a fluorinated phosphate, and an electrolyte (LiPF6, and the like) is used. The fluorinated phosphate has a self-extinguishing function, and the electrolyte solution to which the fluorinated phosphate is added is expected to be a flame-retardant electrolyte solution. Additionally, Patent Literature I discloses that the battery performance may be enhanced by changing the solvent to a mixed solvent of a fluorinated phosphate, and a chain ester andlor a cyclic ester. Patent Literature 2 discloses that it is further preferred that a cyclic carbonate and a chain carbonate are mixed into the solvent as the solvent of the electrolyte solution. [00071 In addition, Patent Literature 3 discloses that charge and discharge properties of the battery is improved by adding a vinylene carbonate compound andlor a vinyl ethylene carbonate compound to a phosphate-based electrolyte solution. [00081 Patent Literature 4 discloses that when a fluorinated phosphate and a specific fluorine-containing solvent such as a fluorinated ether are mixed and used, the non-aqueous electrolyte solution exhibits high flame-retardant properties, and has high electrolyte-dissolving properties, and exhibits good ionic conductivity. [00091 Meanwhile, Patent Literature 5 discloses a non-aqueous electrolyte solution secondary battery comprising an electrolyte solution which contains a polymeric phosphate having two or more phosphate groups in the molecule, together with a chain phosphate such as trimethyl phosphate, and teaches that the secondary battery has good load properties and high safety. The polymeric phosphate is used herein as an additive solvent to form a film having high lithium ion permeability on the surface of the negative electrode and thereby improve the load properties. Citation List Patent Literature ~00101 Patent Literature 1: Japanese Patent No. 3821495 Patent Literature 2: Japanese Patent Laid-Open No. 2008-021560 Patent Literature 3: Japanese Patent Laid-Open No. 2002-203597 Patent Literature 4: Japanese Patent Laid-Open No. 2012-094491 Patent Literature 5: Japanese Patent Laid-Open No. H11-273731 Summary of Invention Technical Problem [00111 I t has been known that an electrolyte solution containing a fluorinated phosphate is flame-retardant and has a high resistance to oxidation. However, when a positive electrode active material which operates at a high electric potential is used, sometimes the decomposition reaction of the electrolyte solution occurs at a contact part of the positive electrode and the electrolyte solution, and then the product of the decomposition at the positive electrode is reduced at the negative electrode, which causes the problems such as the generation of gas and the deterioration in charge and discharge cycle characteristic. In a lithium secondary battery comprising a positive electrode active material which exhibits a high electric potential of 4.5 V or more, in particular, the decomposition of the electrolyte solution readily occurs at the positive electrode, and therefore the further improvement in cycle characteristic at a high temperature of 45°C or more, for example, is desired. [0012l The object of one embodiment of the invention is to provide a nonaqueous secondary battery wherein the decomposition of the electrolyte solution is effectively suppressed even under high-voltage and hightemperature conditions, and therefore the battery has excellent long-term cycle characteristic. Solution to Problem [00131 An embodiment of the invention relates to a lithium secondary battery comprising a positive electrode, a negative electrode and a non-aqueous electrolyte solution, wherein the non-aqueous electrolyte solution contains a phosphate polymer represented by the following formula (1) and a fluorinated phosphate represented by the following formula (2). [00141 wherein RI to R5 each independently represents aliphatic hydrocarbon group or fluorinated aliphatic hydrocarbon group, wherein the group may have a substituent, and n represents an integer of 1 or more, with the proviso that when n is 2 or more, two or more Rl(s) may be the same as, or different from each other and two or more R4(s) may be the same as, or different from each other. [00151 wherein RG to Rg each independently represents aliphatic hydrocarbon group or fluorinated aliphatic hydrocarbon group, wherein the group may have a substituent, with the proviso that at least one of RG to Rg is fluorinated aliphatic hydrocarbon group. Advantageous Effects of Invention [0016] According to the embodiment of the invention, there may be provided a non-aqueous secondary battery wherein the decomposition of the electrolyte solution is effectively suppressed even under high-voltage and hightemperature conditions, and therefore the battery has excellent long-term cycle characteristic. Brief Description of Drawing [00171 Figure 1 is a sectional view illustrating an embodiment of the lithium secondary battery of the present invention. Description of Embodiments [00181 The secondary battery of the embodiment comprises a positive electrode, a negative electrode, and a non-aqueous electrolyte solution, wherein the electrolyte solution contains a phosphate polymer represented by the formula (1) and a fluorinated phosphate represented by the formula (2). [00191 When the fluorinated phosphate is used as a solvent of an electrolyte solution, the fluorinated phosphate is reduced and decomposes on a surface of a carbon negative electrode, and the charge and discharge properties as the battery is remarkably decreased, although the fluorinated phosphate is a solvent having a high resistance to oxidation. I t has been demonstrated that the reductive decomposition on the negative electrode may be suppressed when the fluorinated phosphate is mixed with a carbonate-based solvent,, and yet the decomposition cannot be completely suppressed and when a positive electrode which operates at a high electric potential is used, in particular, sometimes the decomposition product formed on the positive electrode is further reduced on the negative electrode and a problem of generating a large amount of gas arises. When the phosphate polymer represented by the formula (1) is added to an electrolyte solution containing the fluorinated phosphate, the gas generation caused by the reductive decomposition on the negative electrode of the product of the decomposition of the electrolyte solution, which is formed on the positive electrode, may be suppressed, and thereby the cycle characteristic under high temperature and high voltage may be improved. According to the embodiment, in cycles under high temperature and high voltage, in particular, the reduction in the capacity may be remedied and the gas generation may be suppressed [00201 An example of the secondary battery of the present invention will be described below with respect to each component. [00211 [Electrolyte Solution] The electrolyte solution of the embodiment contains a lithium salt and a non-aqueous solvent, and the non-aqueous solvent contains a phosphate polymer represented by the formula (1) and a fluorinated phosphate represented by the formula (2). 100221 In the phosphate polymer represented by the formula ( I ) , n is preferably 1 or more and 4 or less, more preferably 1 or 2, and n is particularly preferably 1. In other words, a phosphate dimer represented by the following formula (1-1) is preferred as the phosphate polymer represented by the formula (1). [00231 wherein RI to R5 each independently represents aliphatic hydrocarbon group or fluorinated aliphatic hydrocarbon group, wherein the group may have a substituent. LO0241 In the phosphate polymer represented by the formula ( I ) , preferably the phosphate dimer represented by the formula (1-l), RI to R5 each independently represents aliphatic hydrocarbon group or fluorinated aliphatic hydrocarbon group, wherein the group may have a substituent. The fluorinated aliphatic hydrocarbon group is an aliphatic hydrocarbon group having at least one fluorine atom (that i s , at least one hydrogen atom is replaced with fluorine atom). [00251 The aliphatic hydrocarbon group may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group. The fluorinated aliphatic hydrocarbon group may also be a saturated fluorinated aliphatic hydrocarbon group or an unsaturated fluorinated aliphatic hydrocarbon group. Additionally, the aliphatic hydrocarbon group may be linear or branched. The fluorinated aliphatic hydrocarbon group may also be linear or branched. [00261 I t is preferred that each of RI to Rs, the aliphatic hydrocarbon group or the fluorinated aliphatic hydrocarbon group is a saturated linear or branched aliphatic hydrocarbon group, or a saturated linear or branched fluorinated aliphatic hydrocarbon group. In other words, it is preferred that RI is a linear or branched alkylene or fluorinated alkylene group, and it is preferred that each of R2 to R5 is a linear or branched alkyl or fluorinated alkyl group. The fluorinated alkylene group is an alkylene group having at least one fluorine atom (that is, at least one hydrogen atom is replaced with fluorine atom), and the fluorinated alkyl group is an alkyl group having at least one fluorine atom (that is, at least one hydrogen atom is replaced with fluorine atom). LO0271 In addition, the number of carbon atoms in RI, the aliphatic hydrocarbon group or the fluorinated aliphatic hydrocarbon group, is preferably 1 or Inore and 6 or less, more preferably 1 or more and 4 or less, particularly preferably 1 or 2. The number of carbon atoms in each of Rz to R5, the aliphatic hydrocarbon group or the fluorinated aliphatic hydrocarbon group, each independently is preferably 1 or more and 4 or less, more preferably 1 or 2. [00281 It is particularly preferred that RI is a linear or branched alkylene group having a number of carbon atoms of 1 or more and 6 or less, more preferably I or more and 4 or less, particularly preferably 1 or 2, or a linear or branched fluorinated alkylene group having a number of carbon atoms of 1 or more and 6 or less, more preferably 1 or more and 4 or less, particularly preferably 1 or 2. It is particularly preferred that each of Rz to R5 is a linear or branched alkyl group having a number of carbon atoms of 1 or more and 4 or less, more preferably 1 or 2, or a linear or branched fluorinated alkyl group having a number of carbon atoms of 1 or more and 4 or less, more preferably 1 or 2. [00291 Specific and preferred examples of the Ri include -CHz-, -CFz-, -CH2CHz-,- CFzCFz-, -CHzCHzCHz-, -CFzCFzCFz-, -CHzCI'z CHz-, -CH2CHzCHzCHz-, -CFzCFzCFzCFz-, -CHzCFzCFzCHz-, -CHzCFzCFzCFzCHz-, -CFzCHzCHzCHzCHzCFz-, and -CHzCHzCFzCFzCHzCHz-. [00301 Specific and preferred examples of the Rz to R5 include -CH3, -CF3, -CF2H, -CHzF, .CHzCH3, -CHzCF3, -CHzCFzH, -CFzCH3, -CFzCFzH, -CFzCF3, -CHZCH~CH-C~H, zCHzCF3, -CHzCFzCF3, -CFzCFzCF3, -CHzCFzCFzH, -CFzCFzCFzH, -CFzCFzCH3, -CHzCHzCHzCH3, -CHzCHzCHzCF3, -CFZCF~CFZC-FC~F,z CFzCFzCH3, -CFzCFzCFzCFzH, -CHzCFzCFzCFzH, and -CHzCFzCFzCF3. [00311 It is preferred that at least one of Rz to R5 is a fluorinated aliphatic hydrocarbon group, preferably a fluorinated alkyl group, and it is more preferred that two or more of Rz to R5 are fluorinated aliphatic hydrocarbon groups, preferably fluorinated alkyl groups. LO0321 In addition, it is preferred that at least one of, preferably two or more of R2 to R5 is a fluorinated aliphatic hydrocarbon group in which 50% or more, more preferably 60% or more, of hydrogen atoms contained in the corresponding unsubstituted aliphatic hydrocarbon group are replaced with fluorine atom(s). When the content of fluorine atom is high, the withstand voltage property may be further improved, and the deterioration in the capacity of the battery after the cycles may be reduced more effectively even in the case where a positive electrode active material which operates at a high electric potential is used. too331 Although it is preferred that each of RI to R5 is an unsubstituted aliphatic hydrocarbon group or an unsubstituted fluorinated aliphatic hydrocarbon group, more preferably an unsubstituted saturated aliphatic hydrocarbon group or an unsubstituted saturated fluorinated aliphatic hydrocarbon group, R1 to Rg may have a substituent in addition to fluorine atom. Examples of the substituent include at least one selected from the group consisting of amino group, carboxy group, hydroxy group, cyano group, and halogen atoins (for example, chlorine atom, and bromine atom). In addition, the number of carbon atoms is the value including the substituent(s). LO0341 Specific examples of the phosphate polymer represented by the formula (1) include compounds represented by the following formulas. (CF~O)P(O)(OCF~)(OCH20)P(O)(OCF~)(OCF~~, (CF~CH~~)P(O)(OCH~CF~)(~CH~CHZ~)P(O)(OCH~CF~(OCH~CF~), (CF~CH~O)P(O)(OCHZCF~)(OCH~CH~~)P(O)(OCH~CF~)(OCH~), (CH~~)P(O)(OCHZCF~)(OCH~CHZ~)P(O)(OCHZCF~)(~CH~~, (CF~CHZ~)P(O)(OCH~CH~~(OCH~CH~~C)HP2(CHO)3)((OO C H2CFd, (CH~CHZ~)P(O)(OCHZCH~)(~CH~CHZ~)P(O)(OCHZCH~)(OCHZCH~), (CF~CF~CH~~)P(O)(OCH~CFZCF~)(~CHZCF~CH~~)P(O)(OCHZCF~)(OCH~ (CH~~)P(O)(OCH~)(OCH~CFZCFZCHZ~)P(O)(OCH~)(OCH~), (CF~HCF~CH~~)P(O)(OCH~CF~CF~H)(OCH~CF~CF~CH~~)P(O)(OCH~H ) ( O C H ~ C F ~ C F ~ H ) , (CH~CH~O)P(O)(OCH~CH~)(OCF~CH~CH~CH~CH~CF~O)P(O)(OCH~CH~)(OCH 2CH3), (CH~CH~~)P(O)(OCH~CH~)(~CH~CH~CF~CF~CH~CH~~)P(O)(OCH~CH~)(~2CH3), and (CF~CHZ~)P(O)(OCH~CF~)(~CHZCHZ~)P(O)(OCHZCF~)(OCH~CH~~)P(O)(OC HzCF3)(0CHzCF3) [00351 The phosphate polymer represented by the formula (1) may be obtained by, for example, esterifying phosphorus oxychloride and a polyhydric alcohol having a target structure under cooling with ice. And then, the residual oxychloride group may be removed as necessary by adding a monohydric alcohol to the reaction mixture and esterifying the oxychloride group. lo0361 The content of the phosphate polymer represented by the formula (1) in the whole solvent may be preferably, but not limited to, 0.1 to 15 vol%, more preferably 0.1 to 7 vol%, further more preferably 0.5 to 5 ~01%. When the content of the phosphate polymer represented by the formula (1) in the whole solvent is 0.1 vol% or more, the decomposition of the electrolyte solution is more suppressed and a good long-term cycle characteristic may be achieved. In addition, when the content of the phosphate polymer represented by the formula (1) in the whole solvent is 15 vol% or less, the increase in the viscosity of the electrolyte solution may be suppressed. [00371 In addition, the phosphate polynler represented by the formula (1) may be used singly or in combination of two or more. Lo0381 In the fluorinated phosphate represented by the formula (21, RG to Rs each independently represents aliphatic hydrocarbon group or fluorinated aliphatic hydrocarbon group, wherein the group may have a substituent, with the proviso that at least one of RG to Rs is fluorinated aliphatic hydrocarbon group. [00391 The aliphatic hydrocarbon group may be a saturated aliphatic hydrocarbon group or an unsaturated aliphatic hydrocarbon group. The fluorinated aliphatic hydrocarbon group may also be a saturated fluorinated aliphatic hydrocarbon group or an unsaturated fluorinated aliphatic hydrocarbon group. Additionally, the aliphatic liydrocarbon group may be linear or branched. The fluorinated aliphatic hydrocarbon group may also be linear or branched. [00401 It is preferred that each of RG to Rs, the aliphatic hydrocarbon group or the fluorinated aliphatic hydrocarbon group is a saturated linear or branched aliphatic hydrocarbon group, or a saturated linear or branched fluorinated aliphatiic hydrocarbon group. In other words, it is preferred that each of RG to Rs is a linear or branched alkyl or fluorinated alkyl group, and it is preferred that at least one of RG to Rs is a fluorinated alkyl group. [00411 In addition, the number of carbon atoms in each of RG to Ra, the aliphatic hydrocarbon group or the fluorinated aliphatic hydrocarbon group (preferably alkyl group or fluorinated alkyl group), each independently is preferably 1 or more and 4 or less, more preferably 1 or more and 3 or less. When the number of carbon atoms in the aliphatic hydrocarbon group or the fluorinated aliphatic hydrocarbon group is 4 or less, the increase in the viscosity of the electrolyte solution may be suppressed and the electrolyte solution may penetrate more readily into micropores in the electrodes and the separator, and the ionic conductivity may be enhanced and the current value may be better in the charge and discharge properties of the battery. LO0421 It is particularly preferred that each of RG to RS is a linear or branched alkyl group having a number of carbon atoms of 1 or more and 4 or less, more preferably 1 or more and 3 or less, or a linear or branched fluorinated alkyl group having a number of carbon atoms of 1 or more and 4 or less, more preferably 1 or more and 3 or less. 100431 As described above, at least one of RG to Rs is a fluorinated aliphatic hydrocarbon group, preferably a fluorinated alkyl group, and it is preferred that all of RG to Rs are fluorinated aliphatic hydrocarbon groups, preferably fluorinated alkyl groups. LO0441 In addition, it is preferred that at least one of, preferably all of RF to Rs is a fluorinated aliphatic hydrocarbon group in which 50% or more, more preferably 55% or more, of hydrogen atoms contained in the corresponding unsubstituted aliphatic hydrocarbon group are replaced with fluorine atom(s). When the content of fluorine atom is high, the withstand voltage property nlay be further improved, and the deterioration in the capacity of the battery after the cycles may be more reduced even in the case where a positive electrode active material which operates at a high electric potential is used. [00451 Although it is preferred that each of RG to Rs is an unsubstituted aliphatic hydrocarbon group or an unsubstituted fluorinated aliphatic hydrocarbon group, more preferably an unsubstituted saturated aliphatic hydrocarbon group or an unsubstituted saturated fluorinated aliphatic hydrocarbon group, RG to Rs may have a substituent in addition to fluorine atom. Examples of the substituent include at least one selected from the group consisting of amino group, carboxy group, hydroxy group, cyano group, and halogen atoms (for example, chlorine atom, and bromine atom). In addition, the number of carbon atoms is the value including the substituent(s). LO0461 Examples of the fluorine-containing phosphate include 2,2,2- trifluoroethyldimethyl phosphate, bis(trifluoroethy1)methyl phosphate, bis(trifluoroethyl)ethyl phosphate, tris(trifluoromethy1) phosphate, pentafluoropropyldimetliyl phosphate, heptafluorobutyldi~nethypl hosphate, trifluoroethyltnethylethyl phosphate, pentafluoropropylmethylethyl phosphate, heptafluorobutylmethylethyl phosphate, trifluoroethylmetliylpropyl phosphate, pentafluoropropylmethylpropyl phosphate, heptafluorobutylmethylpropyl phosphate, trifluoroethylmethylbutyl phosphate, pentafluoropropylmethylbutyl phosphate, heptafluorobutylmethylbutyl phosphate, trifluoroethyldiethyl phosphate, pentafluoropropyldiethyl phosphate, heptafluorobutyldiethyl phosphate, trifluoroethylethylpropyl phosphate, pentafluoropropylethylpropyl phosphate, heptafluorobutylethylpropyl phosphate, trifluoroethylethylbutyl phosphate, pentafluoropropylethylbutyl phosphate, heptafluorobutylethylbutyl phosphate, trifluoroethyldipropyl phosphate, pentafluoropropyldipropyl phosphate, heptafluorobutyldipropyl phosphate, trifluoroethylpropylbutyl phosphate, pentafluoropropylpropylbutyl phosphate, heptafluorobutylpropylbutyl phosphate, trifluoroethyldibutyl phosphate, pentafluoropropyldibutyl phosphate, heptafluorobutyldibutyl phosphate, tris(2,2,3,3-tetrafluor~prop~l) phosphate, tris(2,2,3,3,3-pentafluoropropyl)p hosphate, and tris(2,2,2- trifluoroethyl) phosphate (hereinafter, also abbreviated as PTTFE). Among them, t,ris(2,2,2-trifl~o~oethyplh) osphate (PTTFE), which is represented by the following formula (41, is preferred because the effect of suppressing the decomposition of the electrolyte solution at a high electric potential is high. [00471 The content of the fluorinated phosphate represented by the formula (2) in the whole solvent may be preferably, but not limited to, 5 to 70 ~01%. [00491 In addition, the fluorinated phosphate represented by the formula (2) may be used singly or in combination of two or more. [0050l It is preferred that the electrolyte solution of the embodiment further contains a fluorinated ether represented by the following formula (3) as the solvent. [00511 wherein RII and R12 each independently represents alkyl group or fluorinated alkyl group, with the proviso that at least one of RII and Rlz is fluorinated alkyl group. [00521 When the electrolyte solution contains the fluorinated ether, the viscosity of the electrolyte solution may be reduced and the conductivity of the electrolyte solution may be enhanced, while the resistance to oxidation of the electrolyte solution is maintained. LO0531 It is preferred that the total number of carbon atoms in RII and Rlz, the alkyl group or the fluorinated alkyl group, is 10 or less. The alkyl group or the fluorinated alkyl group may be linear or branched. In addition, it is preferred that the fluorinated alkyl group is a fluorinated alkyl group in which 50% or more, more preferably 60% or more, of hydrogen atoms contained in the corresponding unsubstituted alkyl group are replaced with fluorine atom(s). When the content of fluorine atom is high, the withstand voltage property may be further improved, and the deterioration in the capacity of the battery after the cycles may be reduced more effectively even in the case where a positive electrode active material which operates at a high electric potential is used. lo0541 As the fluorinated ether, a compound represented by the following formula (5) is preferred. LO0551 wherein 11 and m each independently is 1 to 8, and XI to XG each independently is fluorine atom or hydrogen atom, with the proviso that at least one of X1 to X3 and X4 to XG is fluorine atom. LO0561 From the standpoint of the withstand voltage property and the compatibility with other electrolytes, the fluorinated ether is more preferably a compound represented by the following formula (6). [00571 wherein n is 1 to 7, m is 1 to 8, and X1 to XG each independently is fluorine atom or hydrogen atom, with the proviso that at least one of X1 to X3 and x" to XG is fluorine atom. [00581 Examples of the fluorinated ether compound include CF30CH3, CF~OCZHGF(,C FZ)ZOCH~F, (CFZ)ZOCZHC~F,~ (CFZ)CHZO(CFZ)CF~, F(CFZ)~OCHF~(C, Fz)30CzHs, F(CFZ)*OCH~F,( CFZ)~OCZHF(~C,F z)sOCH3, F(CFz)sOCzHs, F(CFz)aOCH3, F(CFz)sOCzHs, F(CFz)gOCH3, CF3CHzOCH3, CF~CHZOCHFZC,F 3CFzCHzOCH3, CF~CFZCHZOCHFCZF, ~CFZCHZO(CFZ)ZH, CF~CFZCHZO(CFZ)ZHFC,F zCHzOCH3, (CF~)(CFZ)CHZO(CFZ)ZH, H(CFz)zOCHzCH3, H(CFZ)Z~CHZCF~,H(CFZ)ZCHZ~CHF~, H(CFZ)ZCH~O(CFZ)ZHH(C, FZ)ZCHZO(CFZ)~HH(C, FZ)~CHZO(CFZ)ZH, H(CHF)ZCHZO(CFZ)ZH(C, F3)zCHOCH3, (CF3)zCHCFzOCH3, CF3CHFCFz0CH3, CF~CHFCFZOCHZCHC~F,~ CHFCFZCHZOCHFZ, CF~CHFCF~OCHZ(CF~)CZF,~ CHFCFZOCHZCFZCFZHH(C, FZ)~CHZO(CFZ)ZH, CH~CHZO(CFZ)~aFnd, F(CFz)aCHzO(CFz)zH. [00591 The content of the fluorinated ether compound represented by the formula (3) in the whole solvent is preferably 10 vol% or more and 90 vol% or less, more preferably 20 vol% or more and 85 vol% or less. There is a tendency that when the content of the fluorinated ether compound is low, the viscosity of the electrolyte solution may be higher, and therefore the conductivity may be reduced and the capacity in the cycles may be reduced. Meanwhile, when the content of the fluorinated ether compound is high, the dielectric constant of the electrolyte solution may be lower, and therefore a supporting salt may not be dissociated and the capacity may be reduced similarly. [0060l In addition, the fluorinated ether represented by the formula (3) may be used singly or in combination of two or more. [00611 Examples of the other solvents which may be used in the electrolyte solution include aprotic solvents, including cyclic carbonates such as propylene carbonate (PC), ethylene carbonate (EC), butylene carbonate (BC), and vinylene carbonate (VC); chain carbonates such as dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), and dipropyl carbonate (DPC); ethylene carbonate derivatives; propylene carbonate derivatives; and aliphatic carboxylates such as methyl formate, methyl acetate, and ethyl propionate. The aprotic solvent may be used singly or in combination of two or more. LO0621 It is preferred that the electrolyte solution of the embodiment further contains a carbonate compound as the solvent. When the electrolyte solution contains a carbonate compound, the ionic dissociability of the electrolyte solution may be enhanced and the viscosity of the electrolyte solution may be reduced, and therefore the ionic mobility may be enhanced. LO0631 Examples of the carbonate compound include the cyclic carbonates and the chain carbonates as described above. Namely, examples of the carbonate compound include ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), vinylene carbonate (VC), dimethyl carbonate (DMC), diethyl carbonate (DEC), ethyl methyl carbonate (EMC), and dipropyl carbonate (DPC). In addition, examples thereof also include fluorinesubstituted carbonate conlpounds such as 4-fluoroethylene carbonate (FEC). [00641 The content of the carbonate compound in the whole solvent is preferably 1 to 50 vol%, more preferably 5 to 40 ~01%. [00651 In addition to the above-described solvents, examples of the solvent include aprotic organic solvents, including y-lactones such as y-butyrolactone, chain ethers such as 1,2-ethoxy ethane (DEE) and ethoxy methoxy ethane (EME), cyclic ethers such as tetrahydrofuran and 2-methyltetrahydrofuran, dimethyl sulfoxide, 1,3-dioxolane, formamide, acetoamide, dimethylformamide, dioxolane, acetonitrile, propylnitrile, nitromethane, ethyl monoglyme, phosphoric acid triesters, trimethoxy methane, dioxolane derivatives, sulfolane, methyl sulfolane, 1,3-dimethyl-2-imidazolidinon3e-, methyl-2-oxazolidinone, propylene carbonate derivatives, tetrahydrofuran derivatives, ethyl ether, 1,3-propanesultone, anisole, N-methylpyrrolidone, and fluorinated carboxylates. The solvent may be used singly or in combination of two or more. to0661 Examples of the lithium salt (supporting salt) to be dissolved in the electrolyte solution include, but not limited to, LiPF6, LiAsFc, LiAIC14, LiC104, LiBF4, LiSbFc, LiCF3S03, LiC4FgC03, LiC ( C F ~ S O ~L)~~N, (CF~SOZ)Z, ~i~(CzFtiSOz)Lzi,B loCllo, lithium salts of lower aliphatic carboxylic acids, chloroborane lithium, lithium tetraphenylborate, LiC1, LiBr, LiI, and LiSCN. Lo0671 The concentration of the lithium salt in the electrolyte solution is preferably 0.5 to 1.5 molll. When the concentration of the lithium salt is within the range, the density, the viscosity, the electric conductivity, and the like may be easily adjusted to the appropriate ranges. [0068l [Positive Electrode] In the embodinlent of the invention, the positive electrode active material is not particularly limited, provided that the inaterial is capable of intercalating lithium ions during charging and deintercalating lithium ions during discharging, and any of known materials may be used. [00691 Examples of the positive electrode active material include lithium manganates having layered structure or lithium manganates having spinel structure such as LiMnOz and Li,Mnz04 (0