This application claims the benefit of priority based on the 24-day Korea Patent Application No. 10-2017-0158265 November 2017, and all information disclosed in the literature of the Korea patent application are included as part of the specification.
[2]
The present invention relates to a secondary battery that is an electrode assembly and an electrolyte contained in a pouch, and more particularly, CID: This is shorter than the operation time of the (Current Interrupt Device current interruption device) safety relates to improved secondary battery.
[3]
BACKGROUND
[4]
Secondary batteries are widely used in vehicles, such as various digital devices, and the vehicle has a feature capable of repetitive charging and discharging. And, it continues being made in research and development to increase efficiency and to improve safety. In other words, a laptop, a secondary battery is applied to various fields such as mobile phones, cars must be secured with safety as well as performance.
[5]
However, high-capacity / high energy toward the safety of the secondary battery is achieved development with an emphasis on improved safety during product development, because more vulnerable. In particular, secondary batteries, since a risk of over-filling is accomplished when the ignition block of overcharge is the item that should be considered important for safety design.
[6]
Accordingly, there is achieved a wide range of additives and improved fire safety at the cell level (Cell level) to prevent material, such as by adding the electrolyte to prevent in advance the possibility of ignition due to overcharging.
[7]
Also, CID (Current interrupt Device) When a built-in secondary battery (or configured therein) the internal pressure rises in the overcharge situation, and blocks the current supplied by the CID is operated.
[8]
That is, as shown in FIGS. 1a 1b, the pouch 10 within the electrode assembly 30 and the electrolyte is embedded tab connection portion 31 of the electrode assembly 30 through the lead (21, 22) prepared to be connected to the outside and is adapted to charge and discharge the current through the leads.
[9]
The lead is being formed in a structure that is inserted into the sealing portion formed along the periphery of the pouch 10, as a structure CID is applied, one end and the tab connecting the first lead 21 connected to 31, the first lead ( 21) at one end it is connected and the other end of the pouch (10) and a second lead (22) leading to the outside, and each of the first lead 21 and second lead 22 has the second adhesive in the respective inner sealing parts surface is bonded through the means 50, each portion is achieved through a bonding adhesive (60).
[10]
Then, the standing overcharge the yirwojyeo pouch 10. When pressure rises in the inside (that is, after the vaporization of the electrolyte solution caused by the overcharge pouch is inflated), the first lead 21 and second lead 22 are sealed portion is part of the fracture is connected by means of an adhesive (60) is fixed on the inner side is cut off the current supply (see the broken state in Fig. 3).
[11]
However, a problem arises in safety in overcharging the battery even when the ignition heat emissions do not overcharge if yirwojiji properly. Thus, the measures to prevent the excessive charging at a low SOC (status of charging) is required even if the above structure is the same CID is applied.
[12]
Detailed Description of the Invention
SUMMARY
[13]
Therefore, ahead of the separation point of the first lead and the second lead to the CID is applied, even if operating time of the CID is turned delayed to avoid the problem of (a first lead and a separation of the second lead late yirwojyeo) ignition occurs ignited it is a primary object of the present invention to provide a secondary battery which can further lower the possibility of occurrence.
[14]
Problem solving means
[15]
The secondary battery of the present invention for achieving the above object, the pouch; The electrode assembly to form a mounted in the pouch, the electrode and the membrane are the electrodes of the electrode tab extends from each end doedoe configured are alternately stacked to overlap in a state combined with a side tab connection; One end connected to the first lead and the second lead connected to the tap connection and the other end has a second lead leading to the pouch outside, and each of the first lead and the second lead is fixed to the inner surface of the pouch lead; And adhesive means coupling said first lead and second lead and has a conductivity; Including, and expands the pouch internal gas pressure rises being yirwoji the first lead and the separation of the second lead, wherein the adhesive means is a gas are subjected to more than a predetermined high voltage when decomposed to promote the rise of the pressure characterized in that the high-voltage decomposing material generating gas-containing.
[16]
Adhesive means in accordance with the present invention, the metal particles to impart conductivity; The adhesive material for imparting adhesive properties; Secondary battery comprising; when a high voltage is applied to the high-voltage decomposing substance for the gas.
[17]
In the preferred embodiment, the high-voltage decomposing material is a polymer that decomposes at a high voltage. The polymer fluorine-containing material can be a substituted aromatic compound. Alternatively, the high-voltage decomposing material is Li 2 Co 3 may be a material containing.
[18]
Then, the adhesive means of the present invention is a high voltage degradation products contained in the range 0.1wt% to 5wt%, the metal particles comprise 20wt% to 90wt% range, the adhesive material may be included in the range 5wt% to 40wt% .
[19]
In another embodiment of the present invention, there is also a second adhesive means for securing the first lead and the second lead in the pouch can be contained in the above high voltage degradation products. However, at this time, the high voltage degradation products contained in the second adhesive means is fixed to the extent the adhesion of the second adhesive means is further larger than the adhesive force of the adhesive means.
[20]
Effects of the Invention
[21]
The present invention having the configuration as described above, it is possible when a high voltage is input by the overcharging by blocking a current supply more quickly than the conventional structure because the high-voltage decomposing matter is decomposed generate a gas even further lower the possibility of ignition.
[22]
Brief Description of the Drawings
[23]
Figure 1a is a perspective view showing the external appearance of a typical pouch-type secondary battery shown.
[24]
Figure 1b is a form consisting of a CID in the sealing part of the pouch type secondary battery shown in Figure 1a showing a cross-sectional view.
[25]
Figure 2 is a view showing a cross-sectional view the CID constructed in accordance with a preferred embodiment of the present invention.
[26]
Figure 3 (a separate first lead and a second lead) CID is functional in the structure of Figure 2. The current supply is a view showing a cross section cut off.
[27]
Figure 4 is a side view illustrating, on an enlarged scale, a portion of the first lead and a second lead connected.
[28]
Mode for the Invention
[29]
A detailed description to be easily implemented by those of ordinary skill in the art with respect to the present invention on the basis of the following, that the appended drawings. However, the invention is not to be implemented in many different forms and limited to the embodiments set forth herein.
[30]
Parts not related to the description in order to clearly describe the present invention was omitted, so as to put the same reference numerals for the same or similar elements throughout the specification.
[31]
In addition, the specification and be construed to limited to the terms or words used in the claims general and dictionary meanings are should not, the inventors define as appropriate for the concept of a term to describe his own invention in the best way on the basis of the principle that can be interpreted based on the meanings and concepts corresponding to technical aspects of the present invention.
[32]
The invention doedoe pouch 10, the electrode assembly 30 and the electrolyte is incorporated within, the pouch 10 has additional seal is formed along the periphery of the electrode assembly 30 is the outside via a lead extending through parts of the seal electrically connected to relates to a secondary battery that can be made that can be charged and discharged is now described in detail the embodiment according to the present invention with reference to the accompanying drawings.
[33]
[34]
Example 1
[35]
[36]
Figure 2 If and 3, the secondary battery according to an embodiment of the present invention has a structure CID is applied. That is, the lead is configured to be broken when the first lead 21 and second lead 22 is connected to configuration doedoe the first lead 21 and second lead 22 are joined increases the internal pressure.
[37]
The electrode assembly 30 is embedded within with the electrolyte pouch 10 has a structure laminated in the electrodes (cathode and anode) and a separator are alternately, in a state wherein the electrodes of the electrode tabs extend from each end are combined into one overlap is formed with a tab connection portion (31).
[38]
The tab connection portion 31 is joined to one end of the first lead 21, the other end of the first lead 21 are bonded via the means 40 connected to one end of the second lead 22. And a second Lee 22. The other end of the de is exposed outside the pouch (10) sealing parts. At this time, if the upper surface of the first lead 21 has a pouch 10 is bonded on the second bonding means 50 to the inner surface of the sealing portion above the portion, the second lead 22 has a pouch (10) the inside surface of the seal portion is adhered to the bottom part via the second adhesive means (50). The second adhesive strength of the adhesive means 50 has a first lead 21 and the second has a larger adhesive force than the adhesive means 40 to attach the second lead 22 (i.e., the first leads and the second leads are coupled the adhesive force is, each first lead and second lead is formed to be lower than the bonding affinity to the inner surface bags).
[39]
Then, the first lead 21 and the bonding means 40 is applied to attach the second lead 22 has an electrically conductive (導電 性) to allow current flow. Accordingly, the electrode assembly 30 is gatdoe a structure in which the pouch 10 can be charging or discharging the electricity to the outside through the first lead 21 and second lead 22 (electrolytic solution due to the voltage rise of the overcharge When you by heat generation of the decomposition as a battery), the pouch (10) inside the gas pressure rises expansion electrical connection between the first lead 21 and the second yirueojyeoseo the separation of the lid (22) electrode assembly 30 is cut off.
[40]
At this time, in this embodiment, the ground is subjected to more than a predetermined high voltage the adhesive means (40) for promoting the increase in the gas pressure speed up the operation time of the CID (so that the can be quickly breaking than the first lead and the second lead) decomposes is contained in the high-voltage decomposing substance 41 to generate a gas.
[41]
That is, the adhesive means 40, as shown in Figure 4, the adhesive material 43 and the high voltage to give the metal particles 42 and the adhesive for imparting conductivity is added when decomposing the high-voltage decomposing generating a gas contains a substance (41).
[42]
In this embodiment, the high-voltage decomposing material 41 is a polymer which is decomposed at a high voltage. The polymer fluorine-containing material can be a substituted aromatic compound. Alternatively, the high-voltage decomposing substance 41 Li 2 Co 3 may be a material containing.
[43]
If the said adhesive substance (43) itself having suitable conductivity would be subject does not need to be added to the metal particles 42, it is preferable that increase the conductivity to form a low resistance In metallic appropriate amount of particles (42) is additionally.
[44]
In this embodiment, the adhesive means 40 and the metal particles 42 is contained in the range 20wt% to 90wt%, the adhesive material 43 may comprise from 5wt% to 40wt% range. Then, the high-voltage decomposing substance 41 is preferably contained in the range 0.1wt% to 5wt%.
[45]
The high-voltage decomposing material 41 more quickly and but can separate the first lead 21 and second lead 22, the more rich in the high-voltage decomposing material 41 is an adhesive material to increase the gas production the more the rich in 43 and / or reduced, so the added amount of the metal particles 42 are preferably added in the above range.
[46]
That is, if reducing the amount of adhesive material 43 is lowering the bonding force of the first lead 21 and second lead 22 is reduced and the amount of the metal particles 42, so that the conductivity is reduced and the resistance increases this considering such details the high-voltage decomposing substance 41 is preferably contained in the range 0.1wt% to 5wt%.
[47]
[48]
TABLE 1
compare Experiment 1 Experiment 2 Experiment 3 Experiment 4 Experiment 5
High-voltage degradation products (wt%) 0 0.05 0.1 1 5 10
Resistance of the second lead (mohm) 0.14 0.14 0.15 0.16 0.19 0.31
Full initial resistance (%) 100 100 101 102 105 116
The first lead and the adhesive strength of the second lead (kgf / cm) 3.0 3.0 2.9 2.7 2.1 1.3
Overcharge result (a first lead and a second lead in case of short-pass) Fail Fail Pass Pass Pass Pass

[49]
[50]
The above Table 1, Li is the high-voltage decomposing material (41) 2 Co 3 is a comparison of the experimental relationship between the increase and decrease of the resistance, and adhesion in accordance with the content which is added to the adhesive means 40 is displayed.
[51]
As shown in Table 1, when the high-voltage decomposing substance 41 is contained in the 0.1wt% or more adhesive means (40), the Pass all CID operation examination. However, the resistance and the battery total resistance that occurs in the increases, therefore, the second lead 22, the amount of the high-voltage decomposing material 41 is gradually increased, the first lead 21 and second lead 22 the adhesive can be found that will gradually decrease.
[52]
Accordingly, the first lead 21 and the taking into account the amount of heat generated in accordance with the increase in the adhesive force and the resistance of the second lead 22. In this embodiment, the adhesive means 40, the high-voltage decomposing substance 41 is 0.1wt% to 5wt to be included in an amount of% range is preferred.
[53]
[54]
Example 2
[55]
[56]
Clerical script another embodiment of the present invention, the first lead 21 and the second bonding means 50, also the high-voltage decomposing material (41) to secure the second lead 22 to the pouch 10 is contained.
[57]
That is, not only the adhesive means 40. When the second adhesive means (50) also contains a high voltage degradation products (41) to reduce the content of the high-voltage decomposing substance 41 contained in the adhesive means 40 above the adhesive force such It can be mitigating the problem of a decrease and increase in resistance.
[58]
However, this time is the second bond the high-voltage decomposing substance 41 contained in the unit 50 is fixed to the extent that the adhesive force of the second adhesive means (50) further larger than the adhesive strength of the adhesive means 40 .
[59]
[60]
The present invention having the configuration as described above, when a high voltage is input by the excessive charging high-voltage decomposing substance 41 is because the decomposition of an additional gas to block the more rapid current supply than the prior art structure can further reduce the possibility of ignition .
[61]
The present invention in the above Although the detailed description and specific examples, the invention is not limited thereto, the substrate under the technical scope of the present invention by one of ordinary skill in the art It can be a variety of embodiments within the equivalent scope of the claims.

WE Claims

[Claim 1]
pouch; The electrode assembly to form a mounted in the pouch, the electrode and the membrane are the electrodes of the electrode tab extends from each end doedoe configured are alternately stacked to overlap in a state combined with a side tab connection; One end connected to the first lead and the second lead connected to the tap connection and the other end has a second lead leading to the pouch outside, and each of the first lead and the second lead is fixed to the inner surface of the pouch lead; And adhesive means coupling said first lead and second lead and has a conductivity; Including, and expands the pouch internal gas pressure rises being yirwoji the first lead and the separation of the second lead, wherein the adhesive means is a gas It is subjected to more than a predetermined high voltage when the decomposition to promote an increase in the pressure of the secondary battery containing the high-voltage decomposing material generating gas.
[Claim 2]
The method of claim 1, wherein the metal particles to the adhesive means, impart conductivity; The adhesive material for imparting adhesive properties; Secondary battery comprising; when a high voltage is applied to the high-voltage decomposing substance for the gas.
[Claim 3]
The method of claim 2, wherein the high-voltage secondary batteries have degradation products, characterized in that the polymer is decomposed at a high voltage.
[Claim 4]
4. The method of claim 3 wherein the polymer is a fluorine-rechargeable battery, characterized in that substances containing a substituted aromatic compound.
[Claim 5]
The method of claim 2, wherein the high-voltage decomposing material is Li 2 Co 3 secondary battery, characterized in that materials containing.
[Claim 6]
The method of claim 2, wherein the high-voltage decomposing material in the adhesive means is a secondary battery, characterized in that included in the range 0.1wt% to 5wt%.
[Claim 7]
The method of claim 2, wherein, in the bonding method of metal particles is a secondary battery, characterized in that with a 20wt% to 90wt% range.
[Claim 8]
The method of claim 2, wherein in the adhesive means bonding material is a secondary battery, characterized in that with a 5wt% to 40wt% range.
[Claim 9]
Claim 1 to according to any one of items 8, doedoe the second adhesive means for securing the first lead and the second lead in the pouch containing the high-voltage decomposition products, high voltage degradation included in the second adhesive means material is a secondary battery, characterized in that defined within the adhesive force of the second adhesive means is further larger than the adhesive force of the adhesive means.