KR101505723B1 - Lithium secondary battery comprising elastic clip device and method for preparation the same - Google Patents

Abstract

The present invention relates to an electrode assembly in which an anode, a separator, and a cathode are laminated; A battery case for accommodating the electrode assembly; And a first crimping portion and a second crimping portion facing each other to elastically clamp at least two sides of the battery case, wherein the first crimping portion and the second crimping portion are connected by a coil spring or a leaf spring The present invention relates to a lithium secondary battery and a method of manufacturing the same.
The lithium secondary battery according to the present invention can be easily fixed to the battery case by elasticity when the battery is fixed to the battery case by fixing the clip type elastic structure including the coil spring or the leaf spring to the battery case, It is possible to minimize the gas generated during charging and discharging of the lithium secondary battery and to prevent localized electrochemical side reactions and local gas generation, Performance and safety can be improved.

Description

TECHNICAL FIELD [0001] The present invention relates to a lithium secondary battery including a clip type elastic structure and a method of manufacturing the same.

The present invention relates to a lithium secondary battery including a clip type elastic structure and a method of manufacturing the same.

Recently, interest in energy storage technology is increasing. As the application fields of cell phones, camcorders, notebook PCs and even electric vehicles are expanding, efforts for research and development of electrochemical devices are becoming more and more specified. The electrochemical device is one of the most remarkable fields in this respect, and development of a rechargeable secondary battery has become a focus of attention. In recent years, research and development on the design of new electrodes and batteries have been proceeding in order to improve capacity density and specific energy in developing such batteries.

Among the currently applied secondary batteries, the lithium secondary battery developed in the early 1990s has advantages such as higher operating voltage and higher energy density than conventional batteries such as Ni-MH, Ni-Cd and sulfuric acid-lead batteries using an aqueous electrolyte solution . However, such a lithium secondary battery has disadvantages in that it may be problematic in terms of safety such as ignition and explosion when an organic electrolytic solution is used.

In general, a method of manufacturing a lithium secondary battery includes the steps of preparing a positive electrode film and a negative electrode film by using a positive electrode / negative electrode active material, applying the positive electrode / negative electrode film to a current collector and winding or laminating the separator together with a separator as an insulator, Inserting the electrode assembly into a battery case, injecting an electrolyte into the battery case, sealing the battery case, and performing degassing to remove gas generated during initial charging.

Further, the thus-prepared lithium secondary battery, the reaction to the solid electrolyte lithium ions and the non-aqueous organic solvent in the electrolyte solution during charging; for the formation of (solid electrolyte interface SEI) film, wherein H _2, CO _2, CH _4, CH _2, C ₂ H ₆ , C ₃ H ₈ , C ₃ H ₆ And so on. The gas causes the internal pressure of the battery to rise by about 1.5 to 2.5 kgf / cm 2 or more, and the central portion of the specific surface of the lithium secondary battery is deformed such that the lithium secondary battery bulges in a specific direction due to the increase of the internal pressure , Which causes a local difference in the adhesion between the inner and outer electrode plates of the lithium secondary battery, thereby deteriorating the performance, lifetime, and stability of the lithium secondary battery.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a lithium secondary battery which is capable of applying a constant pressure to a battery case during charging of an electrode assembly by fixing a clip type elastic structure to a battery case, And a lithium secondary battery capable of greatly improving safety, and a method of manufacturing the same.

According to an aspect of the present invention, there is provided an electrode assembly including an anode, a separator, and a cathode laminated to each other; A battery case for accommodating the electrode assembly; And a first crimping portion and a second crimping portion facing each other to elastically clamp at least two sides of the battery case, wherein the first crimping portion and the second crimping portion are connected by a coil spring or a leaf spring The present invention also provides a lithium secondary battery including the clip-like elastic structure.

According to another aspect of the present invention, there is provided a method of manufacturing an electrode assembly, the method comprising: (a) preparing an electrode assembly in which a cathode, a separator, and a cathode are laminated; (B) inserting the electrode assembly into the battery case, injecting and sealing the electrolyte solution; (C) a first crimping portion and a second crimping portion opposed to each other to elastically clamp at least two sides of the battery case to the battery case, wherein the first crimping portion and the second crimping portion are coil springs or Fixing the clip-like elastic structure connected by the leaf spring; (D) initially charging the electrode assembly; And (e) degassing the pre-charged electrode assembly in advance to generate a gas that may be generated in advance, and removing the previously generated gas. The present invention also provides a method of manufacturing a lithium secondary battery.

Furthermore, the present invention provides a middle- or large-sized battery module or a battery pack, characterized in that the plurality of lithium secondary batteries are electrically connected to each other.

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a lithium secondary battery including a clip type elastic structure, and a lithium secondary battery according to the present invention is characterized by fixing a clip type elastic structure including a coil spring or a leaf spring to a battery case, It is possible to easily fix the battery case to the battery case and to apply appropriate pressure continuously to the battery case by the elastic modulus of the spring so as to minimize the gas generated during charging and discharging of the lithium secondary battery, Side reaction and local gas generation can be prevented, so that the performance and life characteristics of the lithium secondary battery can be improved.

Further, the heat generated in the battery can be transmitted and discharged to the outside more quickly, so that the temperature rise in the battery can be prevented, and the explosion and ignition of the battery can be prevented, which is effective in safety of the battery.

1 to 3 show examples of various clip-type elastic structures according to an embodiment of the present invention.
4 and 5 are side views of a lithium secondary battery in which a battery case is fixed to various types of clip-like elastic structures according to an embodiment of the present invention.
6 and 7 are plan views of a lithium secondary battery in which a battery case is fixed to a clip-like elastic structure according to an embodiment of the present invention.

The inventors of the present invention have confirmed that a clip type elastic structure capable of applying a constant pressure to a battery case when charging an electrode assembly is applied to a lithium secondary battery and gas generated in the lithium secondary battery can be suppressed.

Hereinafter, the present invention will be described in detail.

The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms and the inventor may appropriately define the concept of the term in order to best describe its invention It should be construed as meaning and concept consistent with the technical idea of the present invention.

According to an embodiment of the present invention, there is provided a lithium secondary battery comprising: an electrode assembly including a cathode, a separator, and a cathode laminated; A battery case for accommodating the electrode assembly; And a first crimping portion and a second crimping portion facing each other to elastically clamp at least two sides of the battery case, wherein the first crimping portion and the second crimping portion are connected by a coil spring or a leaf spring Like elastic structure.

Generally, a lithium secondary battery reacts with lithium ions in a non-aqueous organic solvent in the electrolyte to generate a gas. This gas raises the internal pressure of the battery and causes the phenomenon that the central portion of the specific surface of the lithium secondary battery is deformed such that the lithium secondary battery bulges in a specific direction due to the increase of the internal pressure, Local differences may occur in adhesion, which may deteriorate the performance, lifetime, and safety of the lithium secondary battery.

The lithium secondary battery according to an embodiment of the present invention is capable of applying a constant pressure to the battery case during charging of the electrode assembly by fixing the clip-like elastic structure to the battery case, thereby minimizing the gas generated during charging and discharging of the lithium secondary battery Not only can a localized electrochemical side reaction and local gas generation be prevented, but also the performance, lifetime and safety of the lithium secondary battery can be greatly improved.

Particularly, according to an embodiment of the present invention, in the above-described clip-like elastic structure, the first pressing portion and the second pressing portion are connected by a coil spring or a leaf spring, And the elastic force of the spring can maintain the appropriate pressure constantly in the battery case, so that the desired effect of the present invention can be achieved efficiently.

According to an embodiment of the present invention, the coefficient of elasticity of the coil spring or leaf spring is 4X10 ³ Kg / ㎣ to 8 × 10 ³ Kg / ㎣, preferably 7 × 10 ³ Kg / ㎣ to 8 × 10 ³ Kg / ㎣, and most preferably 7.5 × 10 ³ Kg / ㎣ to 8 × 10 ³ Kg / 것이. Wherein the elastic modulus of the coil spring or the leaf spring is 4X10 < ³ > If it is less than Kg /,, appropriate pressure can not be maintained in the battery case, and it may be difficult to achieve the desired effect of the present invention.

The material of the coil spring or the leaf spring is not particularly limited as long as it satisfies the elastic modulus, but it is preferable to use a material which does not change its physical properties at a temperature of 60 DEG C or higher.

”형태, “

” 형태 또는 “

” 형태일 수 있으나, 전지케이스에 접촉하여 지속적인 압력을 가할 수 있는 한, 다양한 변형이 가능하다.According to one embodiment of the present invention, in the above-mentioned clip-like elastic structure, the first pressing portion and the second pressing portion are in contact with at least two faces, preferably two or four faces of the battery case, see "

"shape, "

"Form or"

Quot; shape, but various modifications are possible as long as the battery case can be brought into contact with the battery case to apply sustained pressure.

In the above-mentioned clip-like elastic structure, it is preferable that the materials of the first pressing portion and the second pressing portion are made of a material having high elasticity, high strength, or heat resistance, and that the material is made of aluminum, nickel, iron and copper One or a mixture of two or more thereof; Or a plastic resin such as any one selected from the group consisting of PVC (poly (vinyl chloride)), PTFE (polytetrafluoroethylene), PC (polycarbonate) and MC nylon (mono cast nylon) or a mixture of two or more thereof. Of these, aluminum, iron, nickel or copper, which is well-heat-treated, is preferable, and aluminum is most preferable.

In the case where the materials of the first and second pressing portions are used as a material having good heat conductivity, that is, a material having high thermal conductivity, the heat generated in the battery can be transmitted and discharged to the outside more quickly, It is possible to prevent explosion and ignition of the battery. On the other hand, since the temperature rise of the battery is effectively prevented, the additional side reaction in the battery can be further suppressed, thereby doubling the battery safety.

The electrode assembly used in the present invention is preferably at least one selected from the group consisting of a stacked type, a stacked-folded type, and a jelly-roll type, and is more preferable because it can be easily fixed to a clip type elastic structure, . Specifically, in the stacked electrode assembly, a plurality of positive electrodes and negative electrodes are laminated with a separator interposed therebetween, and a positive electrode terminal and a negative electrode terminal protrude from the top.

The battery case used in the present invention is preferably at least one selected from the pouch type, the cylindrical type, and the square type, and the pouch type is more preferable because it is effective for suppressing the gas, but is not limited thereto.

The clip-like elastic structure used in the present invention is formed to be able to elastically clamp by contacting at least two sides, preferably two or four sides, of the battery case.

According to another aspect of the present invention, there is provided a method of manufacturing an electrode assembly, the method comprising: (a) preparing an electrode assembly in which a cathode, a separator, and a cathode are laminated; (B) inserting the electrode assembly into the battery case, injecting and sealing the electrolyte solution; (C) a first crimping portion and a second crimping portion opposed to each other to elastically clamp at least two sides of the battery case to the battery case, wherein the first crimping portion and the second crimping portion are coil springs or Fixing the clip-like elastic structure connected by the leaf spring; (D) initially charging the electrode assembly; And (e) degassing the pre-charged electrode assembly in advance to generate a gas that may be generated in advance, and removing the previously generated gas. The present invention also provides a method of manufacturing a lithium secondary battery.

In the steps (a) and (b), an electrode assembly in which an anode, a separator, and a cathode are laminated is manufactured, the electrode assembly is inserted into a battery case, and an electrolyte is injected and sealed. Any known method is applicable. At this time, the electrode assembly is a stacked electrode assembly, and a plurality of anodes and cathodes can be stacked with a separator interposed therebetween.

The step (c) includes a first crimping portion and a second crimping portion opposed to each other so as to be brought into contact with at least two sides of the battery case to clamp the battery case, and the first crimping portion and the second crimping portion, Or fixing the clip-like elastic structure connected by the leaf spring. The clip-like elastic structure is previously fixed to the battery case before the electrode assembly is initially charged, so that the battery case can be constantly pressed when charging the electrode assembly, It is possible to minimize the gas generated during charging and discharging of the lithium secondary battery. Particularly, since the first crimping portion and the second crimping portion are connected by a coil spring or a leaf spring, it is possible to easily fix the battery case to the battery case due to elasticity when the battery case is fixed, Strong pressure and constant pressure can be maintained in the case, thereby effectively preventing generation of local gas. Here, the charging of the electrode assembly refers to initial charging before degassing and / or charging of the lithium secondary battery after manufacture.

The steps (d) and (e) may include a step of initially charging the electrode assembly, generating a gas that may be generated in the electrode assembly in advance, and degassing the gas generated in advance Step, any method known in the art is applicable. The initial charging condition is not particularly limited, but it is preferably performed at a current of 0.1 C to 1 C and a voltage of 2.5 to 4.5 V. [

Also, the present invention provides a middle- or large-sized battery module or a battery pack, characterized in that the plurality of lithium secondary batteries are electrically connected to each other. The middle or large-sized battery module or the battery pack includes a power tool; An electric vehicle including an electric vehicle (EV), a hybrid electric vehicle (HEV), and a plug-in hybrid electric vehicle (PHEV); Electric truck; Electric commercial vehicle; Or a power storage system is used as a power supply for medium and large-sized devices.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. Rather, the intention is not to limit the invention to the particular forms disclosed, but rather, the invention includes all modifications, equivalents and substitutions that are consistent with the spirit of the invention as defined by the claims.

Figures 1 to 3 illustrate various clip type elastic structures according to embodiments of the present invention.

” 형태을 갖는 제1 압착부(11)와 제2 압착부(12)가 상기 전지케이스의 적어도 두 면 이상과 접촉하여 탄력적으로 클램핑하도록 서로 마주보고 있으며, 상기 제1 압착부(11)와 제2 압착부(12)는 코일스프링(13)에 의해 연결되어 있는 클립형 탄성구조체(10)를 나타낸 것이다. 여기서, 도 1(a)는 코일스프링이 늘어나기 전의 형태이며, 도 1(b)는 전지케이스의 두께에 따라 코일스프링이 늘어난 형태로, 이 경우, 코일스프링을 늘려 전지케이스를 보다 쉽게 고정할 수 있고, 전지케이스에 강한 압력 및 지속적인 압력을 더욱 효과적으로 유지할 수 있다. Specifically, Figures 1 and 2 illustrate an embodiment of the present invention,

(11) and the second crimping portion (12) are in contact with each other so as to elastically clamp at least two sides of the battery case, and the first crimping portion (11) and the second crimping portion The pressing portion 12 shows the clip-like elastic structure 10 connected by the coil spring 13. As shown in Fig. 1 (a) shows a state before the coil spring is stretched, and FIG. 1 (b) shows a state in which the coil spring is stretched according to the thickness of the battery case. In this case, And it is possible to more effectively maintain the strong pressure and the constant pressure in the battery case.

” 형태를 갖는 제1 압착부(21)와 제2 압착부(22)가 상기 전지케이스의 적어도 두 면 이상과 접촉하여 탄력적으로 클램핑하도록 서로 마주보고 있으며, 상기 제1 압착부(21)와 제2 압착부(22)는 판스프링(23)에 의해 연결되어 있는 클립형 탄성구조체(25)를 나타낸 것이다. Fig. 2 is a schematic diagram of an embodiment of the present invention, according to another embodiment of the present invention,

Quot; -shaped first crimping portion 21 and second crimping portion 22 are in contact with at least two sides of the battery case to elastically clamp the first and second crimping portions 21 and 22, 2 compression section 22 shows a clip-like elastic structure 25 connected by a leaf spring 23.

” 형태 및 “

” 형태를 갖는 제1 압착부(31, 41)와 제2 압착부(32, 42)가 상기 전지케이스의 적어도 두 면 이상과 접촉하여 탄력적으로 클램핑하도록 서로 마주보고 있으며, 상기 제1 압착부(31, 41)와 제2 압착부(32, 42)는 양쪽으로 2개의 코일스프링, 즉 제1 코일스프링(33, 43) 및 제2 코일스프링(34, 44)에 의해 연결되어 있는 클립형 탄성구조체(30, 40)를 나타낸 것이다. Each of Figures 3 (a) and 3 (b), according to another embodiment of the present invention,

&Quot; Form "

(31, 41) and second crimping portions (32, 42) having a shape of "contact" are in contact with each other so as to elastically clamp at least two sides of the battery case, and the first crimping portion 31 and 41 and the second crimping portions 32 and 42 are connected to each other by two coil springs, that is, first coil springs 33 and 43 and second coil springs 34 and 44, (30, 40).

4 and 5 are side views of a lithium secondary battery in which a clip-like elastic structure including a coil spring or a leaf spring is fixed in contact with two or four surfaces of a battery case according to an embodiment of the present invention.

” 형태를 갖는 제1 압착부(11)와 제2 압착부(12)가 코일스프링(13)에 의해 연결된 클립형 탄성구조체가 전지케이스(20)와 접촉하여 고정된 리튬 이차전지(100)의 측면도이고, 도 4(b)는 상기 제1 압착부(21)와 제2 압착부(22)가 판스프링(23)에 의해 연결된 클립형 탄성구조체가 전지케이스(20)와 접촉하여 고정된 리튬 이차전지(200)의 측면도로서, 상기 클립형 탄성구조체는 전지케이스의 두 면과 접촉하여 고정되어 있다.Specifically, FIG. 4 (a)

Shaped elastic structure in which the first compression portion 11 and the second compression portion 12 having the shape of "shape" connected by the coil spring 13 come into contact with the battery case 20 and are fixed to the side surface of the lithium secondary battery 100 4B shows a state in which the clip type elastic structure in which the first pressing part 21 and the second pressing part 22 are connected by the plate spring 23 is in contact with the battery case 20, Side elastic structure is fixed in contact with two surfaces of the battery case.

” 형태를 갖는 제1 압착부(51)와 제2 압착부(52)가 양쪽으로 제1 판스프링(53) 및 제2 판스프링(54)에 의해 연결된 클립형 탄성구조체가 전지케이스(20)와 접촉하여 고정된 리튬 이차전지(500)의 측면도이고, 도 5(b)는 상기 제1 압착부(31)와 제2 압착부(32)가 양쪽으로 제1 코일스프링(33) 및 제2 코일스프링(34)에 의해 연결된 클립형 탄성구조체가 전지케이스(20)와 접촉하여 고정된 리튬 이차전지(300)의 측면도로서, 상기 클립형 탄성구조체는 전지케이의 네 면과 접촉하여 고정되어 있다.Fig. 5 (a)

Like elastic structure in which the first pressing portion 51 and the second pressing portion 52 having the first and second pressing portions 51 and 52 are connected to each other by the first plate spring 53 and the second plate spring 54, 5B is a side view of the lithium secondary battery 500 in contact with and fixed to the first and second coils 33 and 32. FIG. A side view of a rechargeable lithium battery 300 in which a clip-like elastic structure connected by a spring 34 is held in contact with a battery case 20 is fixed. The clip-like elastic structure is in contact with four sides of the battery case.

6 and 7 are plan views of a lithium secondary battery in which a battery case is fixed to a clip-like elastic structure according to an embodiment of the present invention.

According to one embodiment of the present invention, the number of the clip-like elastic structures 10 contacting the battery case 20 as shown in FIGS. 6 and 7 (a) may be one, But is not limited thereto. 6 and 7 (b), the number of the clip-like elastic structures 10 contacting the battery case 20 may be two. In this case, when the number of the clip-like elastic constructions 10 is two, the clip-like elastic structural body 10 is fixed to both sides of the battery case 20 as shown in Fig. 7B or the clip-like elastic structural body 10 is fixed so as to be perpendicular to the longitudinal direction of the battery case 20 as shown in Fig. Two of which may be fixed to the battery case 20 in parallel.

The clip-like elastic structure 10 may be contacted at 45% to 90%, preferably 70% to 90%, and most preferably 80% to 90% of the total area of the upper and lower surfaces of the battery case 20 .

6A, when the number of the clip-like elastic structures 10 contacting the battery case 20 is one, preferably, the total area of the upper surface and the lower surface of the battery case 20 To about 90%, preferably from about 70% to 90%, and most preferably from about 80% to 90% of the total weight of the composition.

6 (b), when the number of the clip-like elastic structures 10 contacting the battery case 20 is two, one clip-like elastic structure is about the total area of the top and bottom surfaces of the battery case 20 35% to 45%, preferably about 40% to 45% of the total area of the top and bottom surfaces of the battery case 20 so that the two clip-like elastic structures 10 are in contact with each other, preferably about 70% to 90% Most preferably from about 80% to about 90%.

If the contact area of the clip-like elastic structure 10 is less than 45% of the total area of the top and bottom surfaces of the battery case, the area of application of the pressure of the battery case is small, And the heat release effect may be insignificant.

Example  One

(1) cathode manufacturing

92 wt% of LiCoO ₂ as a positive electrode active material, 4 wt% of carbon black as a conductive agent, and 4 wt% of PVdF as a binder were added to N-methyl-2-pyrrolidone (NMP) as a solvent to prepare a positive electrode mixture slurry . The positive electrode mixture slurry was coated on an aluminum (Al) thin film having a thickness of 20 탆 and dried to prepare a positive electrode, followed by roll pressing.

(2) cathode manufacturing

(PVdF) as a binder and carbon black as a conductive agent in a weight ratio of 96: 2: 2 to N-methyl-2-pyrrolidone (NMP) as a negative electrode active material To prepare a negative electrode mixture slurry. The negative electrode mixture slurry was applied to a copper (Cu) thin film having a thickness of 10 占 퐉 and dried to produce a negative electrode, followed by roll pressing.

(3) Production of lithium secondary battery

An electrode assembly in which the anode, the polyolefin separator, and the cathode prepared in Example (2) were laminated was prepared, inserted into a battery case, and then charged into an ethylene carbonate / propylene carbonate / An electrolytic solution in which 1 M LiPF ₆ was dissolved was injected into a mixed solvent of diethyl carbonate (EC: PC: DEC = 30: 20: 50 wt%) and sealed. At this time, as shown in Fig. 4 (a), the battery case is provided with a first crimping portion 11 and a second crimping portion 12 which are in contact with two surfaces of the battery case so as to elastically clamp the first and second crimping portions 12, 11 and the second pressing portion 12 have an elastic modulus of 8X10 ³ And the clip-like elastic structure 10 connected by the coil spring 13 of Kg / mm was fixed. The electrode assembly was subjected to initial charging at a current of 0.5 C and a voltage of 3 V. The electrode assemblies were subjected to initial charging to generate gas in advance, (degassing) to finally produce a lithium secondary battery.

Example  2

In the production of a lithium secondary battery according to the first embodiment, the elastic modulus 8X10 ³ Kg / ㎣ a coil spring instead of the modulus 7.5X10 ³ Kg / ㎣ the plate and the lithium is performed in the same manner as in Example 1 except for using the spring A secondary battery was manufactured.

Comparative Example

A lithium secondary battery was produced in the same manner as in Example 1 except that the clip-like elastic structure was not fixed to the battery case.

Experimental Example

In order to measure the resistance of the lithium secondary battery according to the present invention, the lithium secondary batteries prepared in Examples 1 and 2 and Comparative Example were used to measure the resistance of 0.5 C charge / 1.0 C discharge from the fourth cycle at a voltage range of 4.5 to 2.5 V The results are shown in Table 1 below.

Capacity decrease after 10 cycles (%) Decrease in capacity after 50 cycles (%) Capacity decrease after 150 cycles (%) Example 1 5%  10% 16% Example 2 8 %  15%  20% Comparative Example  12%  20%  28%

In the case of the lithium secondary battery manufactured in the examples of the present invention, the amount of decrease in capacity after 150 cycles was much smaller than that in the comparative example. In the case of the lithium secondary battery manufactured in the comparative example, Compared with a battery, the gas generated in the lithium secondary battery can not be effectively suppressed, thereby increasing the internal pressure and causing a rapid variation in the capacity of the battery.

Therefore, the lithium secondary battery according to the present invention can fix the clip-like elastic structure to the battery case, so that it is possible to apply a constant pressure to the battery case during charging of the electrode assembly, thereby suppressing the gas generated in the lithium secondary battery, , Life span, and safety can be greatly improved.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

10, 25, 30, 40: clip-like elastic structure
20: Battery case
11, 21, 31, 41, 51:
12, 22, 32, 42, 52:
13, 33, 34, 43, 44: coil springs
23, 53, 54: leaf spring
100, 200, 300, 500: lithium secondary battery

Claims (18)

An electrode assembly in which an anode, a separator, and a cathode are stacked;
A battery case for accommodating the electrode assembly; And
And a first squeezing portion and a second squeezing portion which are in contact with two or three surfaces of the battery case to face each other to elastically clamp the squeezing portion and the second squeezing portion, wherein the first squeezing portion and the second squeezing portion are connected by a coil spring or a leaf spring Wherein the elasticity of the clip-type elastic structure is less than the elasticity of the elastic body. An electrode assembly in which an anode, a separator, and a cathode are stacked;
A battery case for accommodating the electrode assembly; And
And a first pressing part and a second pressing part facing each other to elastically clamp the battery case in contact with four sides of the battery case, wherein the first pressing part and the second pressing part are connected to each other by a coil spring or a leaf spring, A lithium secondary battery comprising a structure,
Wherein a coefficient of elasticity of the coil spring or the leaf spring is in the range of ⁴ × 10 ³ Kg / ㎣ to 8 × 10 ³ Kg /.. The method according to claim 1,
Wherein a coefficient of elasticity of the coil spring or the leaf spring is in the range of ⁴ × 10 ³ Kg / ㎣ to 8 × 10 ³ Kg /.. The method according to claim 2 or 3,
Wherein a coefficient of elasticity of the coil spring or the leaf spring is in the range of ⁷ × 10 ³ Kg / ㎣ to 8 × 10 ³ Kg /.. 3. The method according to claim 1 or 2,
The first and second squeeze portions are "

" shape, "

"Form or"

&Quot;.< / RTI > 6. The method of claim 5,
remind "

&Quot; -type squeeze portion and the second squeeze portion are connected to each other by a first coil spring and a second coil spring. 3. The method according to claim 1 or 2,
And the number of the clip-like elastic structures contacting the battery case is one or two. 3. The method according to claim 1 or 2,
Wherein the clip-like elastic structure is contacted with any one selected from 45% to 90% of the total area of the top and bottom surfaces of the battery case. 9. The method of claim 8,
Wherein the clip-like elastic structure is contacted with any one selected from 70% to 90% of the total area of the top and bottom surfaces of the battery case. 3. The method according to claim 1 or 2,
Wherein the first pressing portion and the second pressing portion are made of a metal or plastic resin. 11. The method of claim 10,
Wherein the metal is one selected from the group consisting of aluminum, iron, nickel, and copper, or a mixture of two or more thereof. 11. The method of claim 10,
Wherein the plastic resin is any one selected from the group consisting of PVC (poly (vinyl chloride)), PTFE (polytetrafluoroethylene), PC (polycarbonate) and MC nylon (mono cast nylon), or a mixture of two or more thereof Secondary battery. 11. The method of claim 10,
Wherein the first pressing part and the second pressing part are made of aluminum. (A) preparing an electrode assembly in which an anode, a separator, and a cathode are laminated;
(B) inserting the electrode assembly into the battery case, injecting and sealing the electrolyte solution;
(C) a first crimping portion and a second crimping portion opposed to each other to elastically clamp at least two sides of the battery case to the battery case, wherein the first crimping portion and the second crimping portion are coil springs or Fixing the clip-like elastic structure connected by the leaf spring;
(D) initially charging the electrode assembly; And
And (e) degassing the pre-charged electrode assembly in advance to generate a gas that may be generated in advance, and removing the previously generated gas. 3. The middle- or large-sized battery module according to claim 1, wherein the plurality of lithium secondary batteries are electrically connected to each other. 16. The method of claim 15,
The middle- or large-sized battery module includes a power tool; An electric vehicle including an electric vehicle (EV), a hybrid electric vehicle (HEV), and a plug-in hybrid electric vehicle (PHEV); Electric truck; Electric commercial vehicle; And a system for power storage. 2. The middle- or large-sized battery module according to claim 1, A middle- or large-sized battery pack comprising a plurality of lithium secondary batteries according to claim 1 or 2 electrically connected thereto. 18. The method of claim 17,
The middle- or large-sized battery pack includes a power tool; An electric vehicle including an electric vehicle (EV), a hybrid electric vehicle (HEV), and a plug-in hybrid electric vehicle (PHEV); Electric truck; Electric commercial vehicle; And a system for power storage, wherein the power supply is used as a power supply for a middle- or large-sized device.

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