Battery, battery pack containing the same, and automobile including battery pack

Abstract

A battery according to an embodiment of the present invention includes an electrode assembly, a housing configured to accommodate the electrode assembly through an opening formed on one side, a cap configured to cover the opening, and a frame coupled to an inner surface of the cap in a state at least partially separated from the cap to form a first space, and having a gas passage portion configured such that gas generated in a second space in which the electrode assembly is accommodated can flow into the first space.

Description

Technical Field

[0001] The present invention relates to a battery, a battery pack including the same, and a vehicle including the battery pack.

[0002] This application claims priority based on Korean Patent Application Nos. 10-2022-0089124 filed on July 19, 2022, 10-2022-0089123 filed on July 19, 2022, and 10-2023-0087994 filed on July 6, 2023, and all the contents disclosed in the specifications and drawings of the applications are incorporated herein.

Background Art

[0003] A secondary battery goes through a charge / discharge process for activation during its manufacturing process and also goes through a degassing process for discharging gas generated inside during charge / discharge.

[0004] Such a degassing process of a secondary battery can be performed by applying a negative pressure to an open portion partially formed in the secondary battery. For example, after partially opening one side of a secondary battery having a sealed structure, the secondary battery can be positioned in a chamber in which a negative pressure is formed. In this case, the internal gas can escape through the open portion formed in the secondary battery.

[0005] Thus, when removing the gas generated inside the secondary battery, when the gas escapes due to the negative pressure, the electrolyte inside the secondary battery may also leak out to the outside.

[0006] Furthermore, during the manufacturing process of a secondary battery, the secondary battery may be transported in a standing state, a lying state, or a state of being turned upside down, and in this process, the internal electrolyte may adhere to the inner wall surface of the housing. In this case, when a negative pressure is applied to the open portion of the secondary battery, there is a risk that the electrolyte adhering to the inner side around the open portion may easily leak out to the outside.

[0007] Alternatively, it is conceivable to arrange the secondary batteries in a specific direction during the transport process. However, even in this case, there is a risk that electrolyte fluid may adhere to the opening for the degassing process due to the fluid flow during transport. Therefore, if negative pressure is applied to the opening for the degassing process, the electrolyte fluid that has adhered to the opening may leak out.

[0008] Therefore, there is a strong need to develop batteries with a structure that can minimize the phenomenon of electrolyte adhering to the openings used for the gas venting process during the manufacturing process. [Overview of the project] [Problems that the invention aims to solve]

[0009] The present invention has been made in view of the above problems, and its purpose is to provide a battery having a structure that can suppress as much as possible the phenomenon of electrolyte adhering to the opening for the gas venting process during the manufacturing process.

[0010] However, the technical problems that this invention aims to solve are not limited in any way to those described above, and other problems not mentioned should be clearly understood by those skilled in the art from the description of the invention below. [Means for solving the problem]

[0011] A battery according to one embodiment of the present invention for solving the above-mentioned problems includes an electrode assembly, a housing configured to accommodate the electrode assembly through an opening formed on one side, a cap configured to cover the opening, and a frame coupled to the inner surface of the cap at least partially separated from the cap to form a first space, and having a gas passage configured to allow gas generated in the second space in which the electrode assembly is housed to flow into the first space.

[0012] The frame may be configured such that communication between the first space and the second space occurs only through the gas passage.

[0013] The cap may be equipped with a venting section configured to allow gas generated inside the housing to be discharged.

[0014] The battery may include a plug configured to seal the gas vent portion.

[0015] The stopper can be formed integrally with the cap by welding the region where the gas venting portion is formed after a gas venting process that discharges gas generated inside the housing.

[0016] The battery may include a valve assembly provided in the first space and configured to open the venting section during a venting process to discharge gas generated inside the housing, and to close the venting section after the completion of the venting process.

[0017] The valve assembly may include a closure configured to be inserted into the venting portion from the first space, and an elastic member located between the closure and the frame, configured to elastically bias the closure toward the venting portion.

[0018] The cap may include a vent portion configured to break as the internal pressure of the housing increases.

[0019] The distance from the center of the cap to the joint between the frame and the cap may be configured to be even greater than the distance from the center of the cap to the vent portion.

[0020] The frame may include an insulating layer formed on a first surface facing the electrode assembly.

[0021] The cap may be configured to have no polarity.

[0022] The battery may include terminals electrically connected to the electrode assembly.

[0023] The battery may include a current collector configured to be coupled to one side of the electrode assembly to electrically connect the electrode assembly and the housing.

[0024] A battery pack according to an embodiment of the present invention for solving the above-described problems includes a battery according to an embodiment of the present invention.

[0025] A vehicle according to an embodiment of the present invention for solving the above-described problems includes a battery pack according to an embodiment of the present invention.

Advantages of the Invention

[0026] According to one aspect of the present invention, it is possible to suppress, as much as possible, a phenomenon in which an electrolytic solution adheres around an opening for a gas venting process during a manufacturing process.

[0027] However, the advantageous effects derived through the present invention are not limited to the above-described effects at all, and other advantageous effects not mentioned will be clearly understood by those of ordinary skill in the art from the description of the invention described below.

[0028] The drawings attached to this specification illustrate desirable embodiments of the present invention and are for the purpose of further understanding the technical idea of the present invention together with the content of the invention. Therefore, the present invention is not to be construed as being limited only to the matters described in the drawings.

Brief Description of the Drawings

[0029] [Figure 1] It is a diagram showing a battery according to an embodiment of the present invention. [Figure 2]This figure shows the structure of the battery shown in Figure 1, in which a gas vent section for the gas venting process is formed. [Figure 3] This figure shows the gas discharge flow when performing the degassing process of the battery of the present invention. [Figure 4] Figure 2 shows a battery structure in which a plug is applied to close the gas vent after the gas venting process is completed. [Figure 5] Figure 2 shows the battery structure in which the gas venting section is closed by welding after the gas venting process is completed. [Figure 6] Figure 2 shows a battery structure in which a valve assembly for opening and closing the gas vent is applied. [Figure 7] This figure shows the gas discharge flow when the gas vent is opened in the battery shown in Figure 6. [Figure 8] Figure 6 shows the open and closed states of the gas vent section due to the operation of the valve assembly in the battery shown. [Figure 9] This figure shows a battery module according to one embodiment of the present invention, in which a vent portion for ventilation is formed in the cap. [Figure 10] Figure 9 is a diagram illustrating the formation position of the vent section and the connection position between the frame and the cap in the battery module shown. [Figure 11] This figure shows the structure of the frame of the present invention in which an insulating layer is formed. [Figure 12] This figure shows the structure of the lower portion of a battery module according to one embodiment of the present invention. [Figure 13] This figure shows the structure of the upper portion of a battery module according to one embodiment of the present invention. [Figure 14] This figure shows a battery pack according to one embodiment of the present invention. [Figure 15] This figure shows an automobile based on one embodiment of the present invention. [Modes for carrying out the invention]

[0030] The terms and words used in this specification and in the claims are not to be interpreted in their ordinary or dictionary sense, but rather in accordance with the principle that inventors may appropriately define the concepts of terms in order to best describe their invention, and are to be interpreted in a sense that corresponds to the technical idea of ​​the present invention. Accordingly, the embodiments and configurations shown in the drawings described herein are merely preferred embodiments of the present invention and do not represent the entire technical idea of ​​the present invention, and it should be understood that there are various equivalents and modifications that can be substituted for them at the time of filing this application.

[0031] The structure of a battery according to one embodiment of the present invention will be described with reference to Figures 1 to 3. Figure 1 is a diagram showing a battery according to one embodiment of the present invention. Figure 2 is a diagram showing the structure of the battery shown in Figure 1 in which a gas venting section for a gas venting process is formed. Figure 3 is a diagram showing the flow of gas discharge when the gas venting process of the battery of the present invention is performed.

[0032] Referring to Figures 1 to 3, a battery 1 according to one embodiment of the present invention may include an electrode assembly 10, a housing 20, a cap 30, and a frame 40. The battery 1 of the present invention may be a rechargeable secondary battery. The battery 1 may be, for example, a cylindrical battery.

[0033] The electrode assembly 10 may include a positive electrode, a negative electrode, and a separator sandwiched between the positive and negative electrodes. The electrode assembly 10 may be, for example, a jelly roll type electrode assembly formed by winding a laminate including the positive electrode, the negative electrode, and the separator. The housing 20 may be configured to house the electrode assembly 10 through an opening formed on one side. The housing 20 may contain a conductive metal. An electrolyte may be contained within the housing 20 together with the electrode assembly 10. The cap 30 may be configured to cover the opening formed on one side of the housing 20. The cap 30 may contain a metal.

[0034] The frame 40 can be bonded to the inner surface of the cap 30, at least partially separated from the cap 30. As the frame 40 is bonded to the cap 30, a first space S1 can be formed between the cap 30 and the frame 40.

[0035] The frame 40 may include a gas passage 41. The gas passage 41 may be configured to allow gas generated in the second space S2, in which the electrode assembly 10 is housed, to flow into the first space. The gas passage 41 may be, for example, a through hole formed in the frame 40. One or more gas passages 41 may be provided.

[0036] As described above, the battery 1 according to one embodiment of the present invention includes a frame 40 bonded to the inner surface of the cap 30, thereby minimizing the phenomenon of electrolyte adhering to the inner surface of the cap 30 due to the flow of electrolyte inside the housing 20 during the manufacturing process of the battery 1. Since the frame 40 is provided with a gas passage 41, gas generated inside the housing 20 can pass from the second space S2 to the first space S1. Therefore, the battery 1 of the present invention can discharge gas through a gas vent 31 formed in the cap 30 at a position corresponding to the first space S1.

[0037] Thus, according to the battery 1 of the present invention, the gas generated inside during the activation process can be smoothly discharged to the outside (see the gas discharge path along the direction of the arrow in Figure 3), and the phenomenon of electrolyte leaking out together with the gas through the gas venting section 31 during such gas discharge can be prevented or minimized.

[0038] In the present invention, the gas vent portion 31 formed in the cap 30 may be formed in advance during the manufacturing of the cap 30, or, conversely, may be formed afterward in order to perform the gas venting process.

[0039] The frame 40 may be configured such that communication between the first space S1 and the second space S2 occurs only through the gas passage section 41. In this case, by adjusting the size of the gas passage section 41, gas generated in the second space S2 can pass smoothly through the gas passage section 41, while the electrolyte cannot pass smoothly through the gas passage section 41. This prevents the electrolyte from moving closer to the gas vent section 31 of the cap 30 as the electrolyte flows during the manufacturing process of the battery 1.

[0040] The cap 30 may include a venting section 31 configured to discharge gas generated inside the housing 20. As described above, the venting section 31 may be formed during the manufacturing of the cap 30, or it may be formed afterward for the venting process. The venting section 31 may be, for example, a through hole formed in the cap 30. The venting section 31 may be formed at a position corresponding to the first space S1.

[0041] Next, with reference to Figures 4 and 5, the plug 50 applied to the battery 1 of the present invention will be described.

[0042] Figure 4 shows the structure of the battery shown in Figure 2, in which a plug is applied to close the gas vent after the gas venting process is completed. Figure 5 shows the structure of the battery shown in Figure 2, in which the gas vent is closed by welding after the gas venting process is completed.

[0043] First, referring to Figure 4, the battery 1 of the present invention may include a stopper 50 configured to seal the gas vent portion 31. The stopper 50 has a size corresponding to the gas vent portion 31, and can seal the gas vent portion 31 by a screw-fit or screw-on method. In other words, the stopper 50 may be a component distinct from the cap 30.

[0044] In contrast, as shown in Figure 5, the plug 50 can be formed integrally with the cap 30 by welding it to the area where the gas vent portion 31 is formed after a gas venting process that discharges gas generated inside the housing 20. In this way, when the plug 50 is joined to the gas vent portion 31 by welding, the airtightness of the housing 20 can be improved.

[0045] Next, with reference to Figures 6 to 8, a valve assembly 60 applicable to the present invention will be described.

[0046] Figure 6 shows the structure of the battery shown in Figure 2, in which a valve assembly for opening and closing the gas vent is applied. Figure 7 shows the gas discharge flow when the gas vent is opened in the battery shown in Figure 6. Figure 8 shows the open and closed states of the gas vent due to the operation of the valve assembly in the battery shown in Figure 6.

[0047] First, referring to Figure 6, the battery 1 may include a valve assembly 60. The valve assembly 60 is applicable in place of the plug 50 described above.

[0048] The valve assembly 60 may be configured to open the venting section 31 during a venting process that discharges gas generated inside the housing 20, and to close the venting section 31 after the completion of the venting process.

[0049] The valve assembly 60 may include a closure 61 and an elastic member 62. The closure 61 may be configured to be inserted into the vent 31 from a first space S1. In this case, the width at the outer end of the vent 31 may be formed to be even smaller than the maximum width of the closure 61 so that the closure 61 does not come out of the battery 1. The closure 61 may be, for example, a spherical metal ball.

[0050] The elastic member 62 may be positioned between the closure 61 and the frame 40 and configured to elastically bias the closure 61 toward the vent 31. That is, the elastic member 62 may be interposed between the closure 61 and the frame 40 in a compressed state. The elastic member 62 may be, for example, a spring.

[0051] The valve assembly 60 may further include a fixing member 63 interposed between the closure 61 and the elastic member 62. The fixing member 63 may be configured such that one side supports the closure 61 and the other side is supported by the elastic member 62. One side of the fixing member 63 may be coupled to the closure 61. The other side of the fixing member 63 may be coupled to the elastic member 62.

[0052] Thus, when the battery 1 of the present invention is equipped with a valve assembly 60, the gas vent portion 31 of the cap 30 can be opened by pressing the closure 61 in a direction that compresses the elastic member 62. When the gas vent portion 31 is opened in this way, as shown in Figure 7, the gas inside can be discharged to the outside of the battery 1 along the direction of the arrow. In other words, when performing the gas venting process, the gas vent portion 31 can be opened by pressing the closure 61 from the outside of the gas vent portion 31, and when negative pressure is applied from the outside of the opened gas vent portion 31, the gas inside the battery 1 can be discharged to the outside.

[0053] Referring to Figure 8, the closure 61 is pressed against the elastic member 62, compressing it and resulting in the gas vent 31 being open (see Figure 8(a)) and the pressure on the closure 61 being released, causing the gas vent 31 to be closed again by the closure 61 (see Figure 8(b)). Thus, when the battery 1 of the present invention is equipped with a valve assembly 60, the gas vent 31 can be opened and closed reversibly by the compression and expansion of the elastic member 62. Therefore, it becomes possible to omit further steps for closing the gas vent 31 after the gas process.

[0054] Next, the vent portion 32 of the present invention will be described with reference to Figure 9. Figure 9 is a diagram showing a battery module according to one embodiment of the present invention, in which a vent portion for ventilation is formed on the cap.

[0055] Referring to Figure 9, the cap 30 may include a vent portion 32. The vent portion 32 may be configured to rupture as the internal pressure of the housing 20 increases. The vent portion 32 may be a region of the cap 30 that is more fragile than the surrounding areas. The vent portion 32 may be, for example, a region that is thinner in thickness than the rest of the cap 30. The vent portion 32 may be, for example, a region in which one or both sides of the cap 30 are cut out. The vent portion 32 may have a shape that extends to form a closed loop surrounding the center of the cap 30. The vent portion 32 may be formed continuously or discontinuously.

[0056] Thus, when the battery 1 of the present invention is equipped with a vent section 32, even if an abnormality occurs in the battery 1, it is possible to prevent the internal pressure of the battery 1 from increasing above a certain level.

[0057] Next, referring to Figure 10 in conjunction with Figure 9, the position of the joint between the cap 30 and the frame 40 of the present invention will be described. Figure 10 is a diagram illustrating the formation position of the vent portion and the joint position between the frame and the cap in the battery module shown in Figure 9.

[0058] Referring to Figures 9 and 10, when the battery 1 of the present invention is equipped with a vent portion 32, the distance D1 from the center of the cap 30 to the joint between the frame 40 and the cap 30 can be formed to be even greater than the distance D2 from the center of the cap 30 to the vent portion 32.

[0059] If the connection point between the frame 40 and the cap 30 were located further inward than the vent portion 32, the weight of the frame 40 might prevent a portion of the cap 30 from being removed due to the rupture of the vent portion 32. In this way, if the rupture of the vent portion 32 is prevented, there is a risk that gas will not be released at the appropriate time. With the above-described configuration of the present invention, when the internal pressure of the battery 1 increases abnormally, the weight of the frame 40 can prevent the rupture pressure of the vent portion 32 from deviating from the design value, thereby improving the safety of the battery 1 during use.

[0060] Next, with reference to Figure 11, the insulating structure applied to the frame 40 of the present invention will be described. Figure 11 shows a structure in which an insulating layer is formed on the frame of the present invention.

[0061] Referring to Figure 11, the frame 40 may include an insulating layer 42 formed on a first surface facing the electrode assembly 10. The cap 30 may contain metal to ensure rigidity, in which case the frame 40, like the cap 30, may contain metal for welding to the cap 30.

[0062] Thus, if the frame 40 contains metal and is conductive, there is a risk of unwanted electrical contact occurring between the frame 40 and the electrode assembly 10 or between the frame 40 and other metal parts. If the frame 40 is provided with an insulating layer 42 as described above, such unwanted electrical contact can be prevented. The insulating layer 42 can be formed, for example, by coating the first surface of the frame 40 with an insulating paint.

[0063] On the other hand, in the battery 1 of the present invention, the cap 30 may be configured to be non-polar. For this reason, the cap 30 may be electrically insulated from the housing 20 and also from the electrode assembly 10. In this way, if the cap 30 is non-polar, when performing the process of discharging high-temperature gas through the gas vent portion 31 provided in the cap 30, and / or when high-temperature gas is discharged due to the rupture of the vent portion 32, it is possible to prevent the occurrence and / or amplification of thermal events (thermal phenomena) due to contact between high-temperature gas and polarized components.

[0064] Next, with reference to Figures 12 and 13, the electrical connection structure and sealing structure of battery 1 according to one embodiment of the present invention will be described illustratively. Figure 12 is a diagram showing the structure of the lower portion of the battery module according to one embodiment of the present invention. Figure 13 is a diagram showing the structure of the upper portion of the battery module according to one embodiment of the present invention.

[0065] Referring to Figures 12 and 13, the battery 1 of the present invention may include a terminal T1 that is electrically connected to an electrode assembly 10. The terminal T1 may be electrically connected, for example, to a first blank portion 11 of the electrode assembly 10. The terminal T1 may be configured to be exposed to the outside of the housing 20 through a closed portion formed on the opposite side of the open portion of the housing 20. The electrical connection between the terminal T1 and the electrode assembly 10 may be made via a first current collector P1. The housing 20 may be electrically connected to a second blank portion 12 of the electrode assembly 10. The electrical connection between the housing 20 and the electrode assembly 10 may be made via a second current collector P2.

[0066] An insulator IS may be interposed between the electrode assembly 10 and the closing portion of the housing 20, or between the first current collector P1 and the closing portion of the housing 20. A gasket for insulation and sealing may be interposed between the terminal T1 and the housing 20. A gasket G for insulation and sealing may be interposed between the cap 30 and the housing 20.

[0067] With this electrical connection structure, the battery 1 of the present invention can utilize terminal T1 as a first electrode terminal and the entire closed portion of the housing 20 as a second electrode terminal T2.

[0068] Next, with reference to Figure 14, a battery pack 3 according to one embodiment of the present invention will be described. Figure 14 is a diagram showing a battery pack according to one embodiment of the present invention.

[0069] Referring to Figure 14, a battery pack 3 according to one embodiment of the present invention may include at least one of the batteries 1 of the present invention as described above. The batteries 1 may be housed in a pack housing 2. The battery pack 3 may include components for electrical connection between the batteries 1 and / or a battery management system (BMS) configured to control the charging and discharging of the batteries 1.

[0070] Next, with reference to Figure 15, an automobile 5 according to one embodiment of the present invention will be described. Figure 15 is a diagram showing an automobile according to one embodiment of the present invention.

[0071] Referring to Figure 15, an automobile 5 according to one embodiment of the present invention includes at least one battery pack 3. The automobile 5 may be configured to operate by being powered by the battery pack 3. The automobile 5 may be, for example, a hybrid electric vehicle (HEV) or an electric vehicle (EV).

[0072] Although the present invention has been described above with reference to limited embodiments and drawings, it goes without saying that the present invention is not limited thereto, and that various modifications and variations can be made by persons with ordinary skill in the art to which the present invention pertains, within the equivalent scope of the technical concept and claims of the present invention. [Explanation of Symbols]

[0073] 1 Battery 2-pack housing 3 Battery Packs 5. Automobile 10 Electrode assembly 11. First plain section 12. Second plain section 20 Housing 30 caps 31. Gas vent section 32 Vent section 40 frames 41 Gas passage section 42 Insulating layer 50 Plug body 60 Valve Assembly 61 Closure 62 Elastic members 63 Fixing member

Claims

1. Electrode assembly and A housing configured to accommodate the electrode assembly through an opening formed on one side, A cap configured to cover the aforementioned opening, A frame comprising a gas passage portion coupled to the inner surface of the cap, at least partially separated from the cap, forming a first space, and configured such that gas generated in the second space housing the electrode assembly can flow into the first space; In a battery that includes, The aforementioned cap is The housing is equipped with a gas vent that is configured to allow gas generated inside the housing to be discharged. The aforementioned battery is The valve assembly provided in the first space includes a valve assembly configured to open the gas venting section during a gas venting process to discharge gas generated inside the housing, and to close the gas venting section after the completion of the gas venting process, The valve assembly is A closure configured to be inserted into the gas vent from the first space, An elastic member is located between the closure and the frame and is configured to elastically bias the closure toward the gas vent portion, A fixing member for fixing the closure to the elastic member, Includes a battery.

2. The aforementioned frame is The battery according to claim 1, wherein communication between the first space and the second space is performed only through the gas passage.

3. The aforementioned cap is The battery according to claim 1, further comprising a vent portion configured to rupture as the internal pressure of the housing increases.

4. The battery according to claim 3, wherein the distance from the center of the cap to the joint between the frame and the cap is greater than the distance from the center of the cap to the vent portion.

5. The aforementioned frame is The battery according to claim 1, further comprising an insulating layer formed on a first surface facing the electrode assembly.

6. The aforementioned cap is The battery according to claim 1, which does not have polarity.

7. The aforementioned battery is The battery according to claim 1, comprising a terminal electrically connected to the electrode assembly.

8. The aforementioned battery is The battery according to claim 7, comprising a current collector coupled to one side of the electrode assembly and configured to electrically connect the electrode assembly and the housing.

9. A battery pack comprising the battery described in any one of claims 1 to 8.

10. An automobile comprising the battery pack described in claim 9.

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