Battery shell, battery and manufacturing method of battery

Abstract

The present disclosure relates to a battery case, a battery, and a method for manufacturing the battery. In order to save the production cost of the battery and improve the efficiency of a battery manufacturing process, the battery case includes an adsorbent in a space of a degassing portion and an adsorbent partition portion formed by a sealing portion.

Description

Technical Field

[0001] The present disclosure relates to a battery case including an adsorbent in a space of a degassing portion and including an adsorbent partitioning portion formed by a sealing portion, a battery, and a method for manufacturing the battery. Background Art

[0002] With the development of electronics, communications and aerospace industries, the demand for secondary batteries as energy sources is increasing rapidly. In particular, with the emphasis on the importance of global environmental protection policies, the electric vehicle market is growing rapidly, and research and development of secondary batteries is being actively carried out both at home and abroad.

[0003] According to the material of the shell that contains the electrode assembly, secondary batteries are divided into pouch type, cylindrical type, square type, etc. The pouch type contains the electrode assembly in a bag made of a flexible polymer material with an uncertain shape. In order to remove the internal gas formed during the initialization process, the electrode assembly contained in the bag undergoes a degassing process, and a degassing space is required in the pouch shell.

[0004] Figure 1 The structure of the existing battery case is briefly shown. Figure 1 The battery case 3 includes an electrode assembly storage part 1 for storing the electrode assembly and a degassing part 2 for performing a degassing process. The degassing part 2 in the battery case 3 is equivalent to the consumption that is cut and discarded after the degassing process. Recently, as the energy density of secondary batteries increases, the size of the battery case is gradually increasing, and the area used as the degassing part is also increasing proportionally.

[0005] However, as the area used as the degassing portion increases, the amount of the battery case that is cut and discarded also increases, which causes problems such as an increase in the production cost of the battery and a decrease in the efficiency of the battery manufacturing process.

[0006] As described above, a technology is needed that can reduce the area of ​​the degassing portion consumed in the battery case to save the production cost of the battery and improve the efficiency of the battery manufacturing process. Summary of the invention

[0007] Technical issues

[0008] The present disclosure provides a battery case, a battery and a method for manufacturing the battery, which include an adsorbent in a space of a degassing portion and an adsorbent partitioning portion formed by a sealing portion in order to save the production cost of the battery and improve the efficiency of the battery manufacturing process.

[0009] Technical Solution

[0010] The battery case according to the present disclosure includes: an electrode assembly receiving portion; a degassing portion formed at one side of the electrode assembly receiving portion and including an adsorbent; and an adsorbent partitioning portion formed by a sealed portion in a space of the degassing portion.

[0011] In one embodiment of the present disclosure, the adsorbent may include a material selected from the group consisting of silica gel, activated carbon, zeolite, carbon fiber, CaO, BaO, MgSO 4 Mg(ClO 4 ) 2 、MgO、P 2 O 5 、Al 2 O 3 , CaH 2 , NaH, LiAlH 4 、CaSO 4 、Na 2 SO 4 、CaCO 3 , K 2 CO 3 and CaCl 2 One or more of the groups consisting of.

[0012] In one embodiment of the present disclosure, a plurality of the sealing portions are formed, and a plurality of unsealed portions that are not sealed may be respectively formed between the plurality of the sealing portions.

[0013] In one embodiment of the present disclosure, the adsorbent partitioning part may include the adsorbent.

[0014] In one embodiment of the present disclosure, the sealing portion may be formed symmetrically with respect to an axis passing through the center of the battery case.

[0015] In one embodiment of the present disclosure, the sealing portion may be formed in a direction perpendicular to a direction of an axis passing through a center of the battery case.

[0016] In one embodiment of the present disclosure, the sealing portion may be formed in parallel with a direction of an axis passing through a center of the battery case.

[0017] In one embodiment of the present disclosure, the degassing portion may include a degassing hole.

[0018] In one embodiment of the present disclosure, a plurality of the degassing holes may be formed.

[0019] The battery according to the present disclosure includes: a battery case according to one of the above embodiments; and an electrode assembly, an electrode assembly storage portion contained in the battery case, including a positive electrode, a negative electrode and a separator arranged between the positive electrode and the negative electrode, including a structure in which the degassing portion of the battery case is removed.

[0020] In one embodiment of the present disclosure, the electrode assembly may be electrically connected to the electrode tab.

[0021] The manufacturing method of the battery according to the present disclosure includes: step (a), preparing a battery case according to one of the above-mentioned embodiments; step (b), accommodating an electrode assembly in an electrode assembly receiving portion of the battery case; step (c), injecting electrolyte into the battery case and sealing the outer periphery of the battery case; step (d), activating the electrode assembly to perform a degassing process; and step (e), removing the degassing portion of the battery case.

[0022] In one embodiment of the present disclosure, the step (d) may include: a step (d-1) of activating the electrode assembly; and a step (d-2) of forming a degassing hole in the degassing portion of the battery case.

[0023] In one embodiment of the present disclosure, in the step (d), the battery casing may be erected to perform a degassing process.

[0024] In one embodiment of the present disclosure, the step (e) may include: step (e-1), sealing at least a portion of a boundary area between the electrode assembly receiving portion and the degassing portion; and step (e-2), removing the degassing portion of the battery case.

[0025] Effects of the Invention

[0026] The degassing part of the present disclosure contains an adsorbent, so that the gas generated during the activation process of the electrode assembly can be removed, the emission of gas harmful to the human body can be reduced, and the battery life characteristics can be improved. In addition, the production cost of the battery can be saved by reducing the use area of ​​the degassing part of the battery shell, and the efficiency of the battery manufacturing process can be improved.

[0027] The present disclosure includes an adsorbent partitioning portion formed by a sealing portion within the space of a degassing portion, and the adsorbent is arranged in the adsorbent partitioning portion to prevent the adsorbent from flowing into the degassing hole or the electrode assembly storage portion for exhausting gas, thereby having the effect of smoothly exhausting the gas generated during the activation process of the electrode assembly.

[0028] The present disclosure can perform the degassing process by standing up the battery case containing the electrode assembly, thereby having the effect of reducing the amount of electrolyte leaking from the inside of the battery case to the outside. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Briefly show the structure of the existing battery casing;

[0030] Figure 2 The structure of a battery housing according to one embodiment of the present disclosure is briefly shown;

[0031] Figure 3 The structure of a battery housing according to another embodiment of the present disclosure is briefly shown;

[0032] Figure 4 The structure of a battery case having degassing holes is briefly shown;

[0033] Figure 5 The structure of a battery according to one embodiment of the present disclosure is briefly shown;

[0034] Figure 6 A flowchart briefly showing a method for manufacturing a battery according to an embodiment of the present disclosure;

[0035] Figure 7 A battery housing according to an embodiment of the present disclosure is briefly shown;

[0036] Figure 8 A battery housing containing an electrode assembly is briefly shown;

[0037] Fig. 9 A battery housing is schematically shown which is filled with electrolyte and has its outer periphery sealed;

[0038] Fig.10 A battery housing having degassing holes is schematically shown;

[0039] Fig.11 A structure in which a battery housing containing an electrode assembly is horizontally arranged in a degassing process is briefly shown;

[0040] Fig.12 A structure in which a battery case containing an electrode assembly is arranged upright in a degassing process is briefly shown;

[0041] Fig.13 The battery is schematically shown with the degassing section removed. DETAILED DESCRIPTION

[0042] The structural or functional descriptions of the embodiments disclosed in this specification or application are merely exemplary and are intended to illustrate the embodiments according to the technical ideas of the present disclosure. The embodiments according to the technical ideas of the present disclosure can be implemented in a variety of ways in addition to the embodiments disclosed in this specification or application, and shall not be construed as limiting the technical ideas of the present disclosure to the embodiments described in this specification or application.

[0043] The battery case, the battery, and the method for manufacturing the battery according to the present disclosure are described in detail below.

[0044] The battery case according to the present disclosure includes: an electrode assembly receiving portion; a degassing portion formed at one side of the electrode assembly receiving portion and including an adsorbent; and an adsorbent partitioning portion formed by a sealed portion in a space of the degassing portion.

[0045] Figure 2 The structure of a battery case according to one embodiment of the present disclosure is briefly shown.

[0046] Reference Figure 2 According to the present disclosure, the battery case 100 includes an electrode assembly receiving portion 10. The battery case 100 may be a bag made of a flexible material. The electrode assembly receiving portion 10 may be formed into a bag shape after a portion of the battery case 100 is stretched by drawing the battery case 100. The electrode assembly receiving portion 10 may prevent the electrode assembly from being separated from the outside of the battery case 100.

[0047] The battery case 100 according to the present disclosure includes a degassing portion 20 formed at one side of the electrode assembly receiving portion 10. The degassing portion 20 is a space for performing a degassing process in a battery formation process.

[0048] The degassing part 20 of the battery case 100 according to the present disclosure includes an adsorbent 21. The electrode assembly is activated through the chemical formation process, and the gas generated inside the battery case 100 can be removed through the degassing process. The gas can be generated during the formation of the solid electrolyte interface (SEI) film at the negative electrode in the electrode assembly. For example, the gas can be CO, CO 2 , H 2 , C 2 H 2 , C 2 H 4 The adsorbent 21 can adsorb CO and CO generated during the electrode assembly activation process. 2 , H 2 , C 2 H 2 , C 2 H 4 The degassing section 20 of the present disclosure includes an adsorbent 21, thereby reducing the emission of gases harmful to the human body. Moreover, compared with the past, the area used as the degassing section in the battery case 100 according to the present disclosure is reduced (refer to Figure 1 Degassing section 2 and Figure 2 The degassing section 20) can save the production cost of the battery and improve the efficiency of the battery manufacturing process.

[0049] The adsorbent 21 may be an organic or inorganic substance capable of adsorbing gas, and may be in the form of particles with pores as required. For example, the adsorbent 21 may include a material selected from silica gel, activated carbon, zeolite, carbon fiber, CaO, BaO, MgSO 4 Mg(ClO 4 ) 2 、MgO、P 2 O5 、Al 2 O 3 , CaH 2 , NaH, LiAlH 4 、CaSO 4 、Na 2 SO 4 、CaCO 3 , K 2 CO 3 and CaCl 2 One or more of the groups consisting of.

[0050] The battery case 100 according to the present disclosure includes an adsorbent partition 30 formed by a sealing portion 22 in the space of a degassing portion 20. The adsorbent 21 may be included in the adsorbent partition 30 formed by the sealing portion 22. Specifically, the adsorbent 21 may be placed in the adsorbent partition 30 formed by the sealing portion 22, and the electrolyte and gas may flow through the unsealed portion 23. By configuring the adsorbent 21 in the adsorbent partition 30, the problem of the adsorbent flowing into the degassing hole or the electrode assembly receiving portion for exhausting gas can be prevented, and the gas generated during the activation process of the electrode assembly can be smoothly discharged.

[0051] A plurality of sealing parts 22 may be formed, and a plurality of unsealed parts 23 that are not sealed may be formed between the plurality of sealing parts 22. The length of each of the plurality of sealing parts 22 may be the same, and the length of each sealing part 22 may vary according to the specification of the degassing part 20. Preferably, the sealing part 22 may have a long length that is not easily broken during the degassing process, or may have a short length that is easy to discharge gas.

[0052] The sealing portion 22 may be formed symmetrically with respect to the axis (Y axis) passing through the center of the battery case 100. Furthermore, the sealing portion 22 may be formed in a direction perpendicular to the axis (Y axis) passing through the center of the battery case 100. Figure 3 The structure of the battery housing according to another embodiment of the present disclosure is briefly shown, referring to Figure 3 The sealing portion 22 may be formed in parallel with the axis (Y axis) passing through the center of the battery case 200 .

[0053] Figure 4 The structure of a battery case having degassing holes formed therein is schematically shown.

[0054] Reference Figure 4, the battery housing 100, 200 may include a degassing hole H in the degassing portion 20. The gas not adsorbed by the adsorbent 21 may be discharged to the outside of the battery housing 100, 200 through the degassing hole H. The degassing hole H may be formed in a space outside the adsorbent partition 30. A plurality of degassing holes H may be formed, and each of the plurality of degassing holes H may be formed to be spaced at a predetermined interval. The degassing hole H may be formed into a shape such as a Y-shape, a cross, an asterisk, a circle, a square, etc. by stamping.

[0055] The battery according to the present disclosure includes: a battery case; and an electrode assembly accommodated in an electrode assembly receiving portion of the battery case and including a positive electrode, a negative electrode, and a separator disposed between the positive electrode and the negative electrode, including a structure in which a degassing portion of the battery case is removed.

[0056] Figure 5 The structure of a battery according to one embodiment of the present disclosure is briefly shown.

[0057] Reference Figure 5 The battery 1000 according to the present disclosure includes a battery housing 100 and an electrode assembly accommodated in an electrode assembly receiving portion 10 of the battery housing 100. The battery housing 100 and the electrode assembly receiving portion 10 may be the same as those described above. Figure 2 The battery case 100 and the electrode assembly housing 10 described above are the same.

[0058] The electrode assembly includes a positive electrode, a negative electrode, and a separator disposed between the positive electrode and the negative electrode. The positive electrode may include a positive electrode active material capable of embedding and desorbing lithium (Li) ions, and the negative electrode may include a negative electrode active material capable of absorbing and desorbing lithium (Li) ions. Moreover, the positive electrode and the negative electrode may also include a binder and a conductive material in the positive electrode active material and the negative electrode active material, respectively, to improve mechanical stability and conductivity. The separator may be configured to prevent an electrical short circuit between the positive electrode and the negative electrode and to generate an ion flow. The type of separator is not particularly limited, but may include a porous polymer film. The electrode assembly may be manufactured in a stacking (stacking) or zigzag stacking (zigzagstacking) manner by alternately stacking a plurality of positive electrodes and negative electrodes and providing a separator between the positive electrode and the negative electrode.

[0059] The battery 1000 may also include an electrolyte in the battery housing 100. The electrolyte may be a non-aqueous electrolyte. The electrolyte may contain a lithium salt and an organic solvent. For example, the organic solvent may include one or more selected from the group consisting of propylene carbonate (PC), ethylene carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), methyl propyl carbonate (MPC), dipropyl carbonate (DPC), vinylene carbonate (VC), dimethyl sulfoxide, acetonitrile, dimethoxyethane, diethoxyethane, sulfolane, gamma-butyrolactone, propylene sulfide and tetrahydrofuran.

[0060] The electrode assembly may be electrically connected to the electrode tab 40. The electrode tab 40 may include a metal having excellent conductivity, for example, may include at least one of aluminum, copper, nickel, and stainless steel (SUS). The electrode tab 40 may be composed of the same material as the current collector to which the electrode tab 40 is attached. For example, the electrode tab 40 attached to the negative electrode current collector having copper as the main component may include copper as the main component. Moreover, the electrode tab 40 attached to the positive electrode current collector having aluminum as the main component may include aluminum as the main component. As required, in order to prevent a short circuit between the electrode tab 40 and the metal layer of the battery case 100, a thin film may be provided between the electrode tab 40 and the battery case 100. The thin film is an insulating film or a hot-melt film, for example, it may include one or more materials selected from polyimide, polypropylene, polyethylene, and polyethylene terephthalate.

[0061] The battery 1000 is a structure in which the degassing portion 20 is removed from the battery case 100 after removing gas generated during activation of the electrode assembly. In order to prevent the electrode assembly from being separated from the electrode assembly receiving portion 10, a sealing area S may be formed on the outer periphery of the battery 1000.

[0062] The manufacturing method of the battery according to the present disclosure includes: step (a), preparing a battery case; step (b), accommodating an electrode assembly in an electrode assembly receiving portion of the battery case; step (c), injecting electrolyte into the battery case and sealing the outer periphery of the battery case; step (d), activating the electrode assembly to perform a degassing process; and step (e), removing the degassing portion of the battery case.

[0063] Figure 6 A flowchart briefly shows a method for manufacturing a battery according to an embodiment of the present disclosure. Figure 7A battery case according to one embodiment of the present disclosure is briefly shown.

[0064] Reference Figure 6 and Figure 7 The manufacturing method according to the present disclosure includes a step S10 of preparing a battery case. In step S10, a battery case 100 including an electrode assembly receiving portion 10, a degassing portion 20, an adsorbent 21, and an adsorbent partitioning portion 30 is prepared. The battery case 100 including the electrode assembly receiving portion 10, the degassing portion 20, the adsorbent 21, and the adsorbent partitioning portion 30 can be the same as that described above. Figure 2 The battery case 100 including the electrode assembly storage part 10, the degassing part 20, the adsorbent 21 and the adsorbent partitioning part 30 is the same as described above. The battery case 100 may include a water-resistant resin, for example, a film form of a laminate of polyolefin resin, metal, nylon resin and polyterephthalate resin.

[0065] Figure 8 A battery case housing an electrode assembly is schematically shown.

[0066] Reference Figure 6 and Figure 8 , the manufacturing method according to the present disclosure includes a step S20 of accommodating an electrode assembly. In step S20, the electrode assembly is accommodated in the electrode assembly receiving portion 10 of the battery case 100. Moreover, the electrode assembly can be accommodated so that the electrode tab 40 is exposed outside the battery case 100. After the electrode assembly is accommodated in the electrode assembly receiving portion 10, a sealing area S can be formed on the outer periphery to prevent the electrode assembly from escaping to the outside of the battery case 100.

[0067] Fig. 9 The battery case is schematically shown filled with electrolyte and sealed at the outer periphery.

[0068] Reference Figure 6 and Fig. 9 According to the manufacturing method disclosed in the present invention, the step S30 of sealing the outer periphery of the battery case after injecting the electrolyte is included. In step S30, the electrolyte is injected into the battery case 100 and the outer periphery of the battery case 100 is sealed. The electrolyte can be injected into the interior of the battery case 100 through the electrolyte injection portion 50. The electrolyte flows from the top to the bottom by gravity, so preferably, the electrolyte can be injected from the top to the bottom of the battery case 100. Moreover, in order to prevent the electrolyte from leaking, the battery case 100 can be configured so that the electrolyte injection portion 50 faces upward and the electrolyte is injected. After the electrolyte is injected into the interior of the battery case 100, the outer periphery of the battery case 100 having the electrolyte injection portion 50 can be sealed to form a sealed area S.

[0069] Fig.10 A battery case having degassing holes formed therein is schematically shown.

[0070] Reference Figure 6 and Fig.10 The manufacturing method according to the present disclosure includes a step S40 of performing a degassing process. In step S40, the electrode assembly is activated to perform the degassing process. Moreover, step S40 may include a step of activating the electrode assembly and a step of forming a degassing hole H in the degassing portion 20 of the battery case 100.

[0071] The activation process of the electrode assembly is a process to complete charging so that the electrode assembly can supply power. The activation process is performed after the battery case 100 is completely sealed, so the charging rate is high and the gas is effectively discharged, so that the battery can be manufactured within a predetermined process time.

[0072] When the activation process is completed, gas may be generated inside the battery housing 100. The gas may be generated during the formation of a solid electrolyte interface (SEI) film at the negative electrode of the battery, and may be CO, CO 2 , H 2 , C 2 H 2 , C 2 H 4 The adsorbent 21 can adsorb CO and CO generated in the activation process. 2 , H 2 , C 2 H 2 , C 2 H 4 And other gases.

[0073] The degassing hole H may be formed in the degassing portion 20 of the battery case 100 by a punching process using a knife or the like. The degassing hole H may be formed in a Y-shape, a cross shape, an asterisk, a circle, a square, or the like. The degassing hole H may be used to perform a degassing process of discharging gas not adsorbed by the adsorbent to the outside of the battery case 100. Fig.11 The structure in which the battery case housing the electrode assembly is horizontally arranged during the degassing process is schematically shown. Fig.12 The structure in which the battery case containing the electrode assembly is placed upright during the degassing process is schematically shown. Fig.11 and Fig.12Usually, in the degassing process, the battery case containing the electrode assembly is horizontally arranged and placed in the chamber to remove the gas. This is to smoothly discharge the gas generated inside the battery case to the outside of the battery case. However, with the horizontal arrangement of the battery case, there is a problem of a large amount of electrolyte leaking through the degassing holes. According to the manufacturing method of the battery disclosed in the present invention, a battery case including an adsorbent and an adsorbent dividing portion is used, and the adsorbent adsorbs the gas generated inside the battery case before the degassing process. The adsorbent dividing portion can fix the position of the adsorbent through a sealing portion, thereby reducing the amount of gas discharged to the outside of the battery case, and preventing the adsorbent from flowing into the degassing holes. Therefore, the battery case can be erected to perform the degassing process, thereby reducing the amount of electrolyte leaking through the degassing holes.

[0074] Fig.13 The battery is schematically shown with the degassing section removed.

[0075] Reference Figure 6 and Fig.13 , the manufacturing method according to the present disclosure includes a step S50 of removing the degassing portion. In step S50, the step of sealing at least a portion of the boundary area between the electrode assembly receiving portion 10 and the degassing portion 20 and the step of removing the degassing portion 20 in the battery case 100 may be included. After the degassing process, the electrolyte inside the battery case 100 may leak through the degassing hole H formed in the degassing portion 20. Therefore, after the electrode assembly receiving portion 10 and the degassing portion 20 are sealed, a cutting line may be set in the sealed area including the degassing portion 20 to remove the degassing portion 20. The manufacture of the battery 1000 according to one embodiment of the present disclosure can be completed by removing the degassing portion 20.

Claims

1. A battery housing, comprising: An electrode assembly storage portion; a degassing portion formed at one side of the electrode assembly receiving portion and comprising an adsorbent; and The adsorbent partitioning portion is formed by a sealed portion within the space of the degassing portion.

2. The battery case according to claim 1, wherein the adsorbent comprises one or more selected from the group consisting of silica gel, activated carbon, zeolite, carbon fiber, CaO, BaO, MgSO4, Mg(ClO4)2, MgO, P2O5, Al2O3, CaH2, NaH, LiAlH4, CaSO4, Na2SO4, CaCO3, K2CO3 and CaCl2. 3 . The battery case according to claim 1 , wherein a plurality of the sealing portions are formed, and a plurality of unsealed portions that are not sealed are respectively formed between the plurality of the sealing portions. The battery case according to claim 1 , wherein the adsorbent partitioning portion includes the adsorbent. 5 . The battery case according to claim 1 , wherein the sealing portion is formed symmetrically with respect to an axis passing through the center of the battery case. 6 . The battery case according to claim 1 , wherein the sealing portion is formed in a direction perpendicular to a direction of an axis passing through a center of the battery case. 7 . The battery case according to claim 1 , wherein the sealing portion is formed in parallel with a direction of an axis passing through a center of the battery case. The battery case according to claim 1 , wherein the degassing portion comprises a degassing hole. 9 . The battery case according to claim 8 , wherein a plurality of the degassing holes are formed.

10. A battery comprising: The battery housing according to claim 1; as well as The electrode assembly is contained in the electrode assembly receiving portion of the battery housing, and includes a positive electrode, a negative electrode, and a separator disposed between the positive electrode and the negative electrode. The degassing portion of the battery case is removed. The battery according to claim 10 , wherein the electrode assembly is electrically connected to the electrode tab.

12. A method for manufacturing a battery, comprising: Step (a), preparing the battery casing according to claim 1; Step (b), accommodating the electrode assembly in the electrode assembly receiving portion of the battery housing; Step (c), injecting electrolyte into the battery housing and sealing the outer periphery of the battery housing; Step (d), activating the electrode assembly to perform a degassing process; as well as Step (e), removing the degassing portion of the battery casing.

13. The method for manufacturing a battery according to claim 12, wherein the step (d) comprises: Step (d-1), activating the electrode assembly; as well as Step (d-2), forming a degassing hole in the degassing portion of the battery casing. 14 . The method for manufacturing a battery according to claim 12 , wherein in the step (d), the battery case is erected to perform a degassing process.

15. The method for manufacturing a battery according to claim 12, wherein the step (e) comprises: Step (e-1), sealing at least a portion of a boundary region between the electrode assembly receiving portion and the degassing portion; as well as Step (e-2), removing the degassing portion of the battery casing.

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