Top cover structure and secondary battery

Abstract

An embodiment of the present invention provides a top cover structure and a secondary battery, which relate to the technical field of secondary batteries. The top cover structure includes a top cover, an explosion-proof valve, a first support member, and a second support member. The top cover is provided with an explosion-proof valve hole. The explosion-proof valve is installed in the explosion-proof valve hole. The first support member and the second support member are both arranged on the inner side of the top cover, and the first support member and the second support member are located on both sides of the explosion-proof valve hole, and a gas channel is formed between the first support member and the second support member, and the gas channel is used for gas to flow to the explosion-proof valve. The first support member and the second support member are both arranged on the inner side of the top cover, and the first support member and the second support member are located on both sides of the explosion-proof valve hole, so that a gas channel is formed between the first support member and the second support member, and the first support member and the second support member will support the battery cell, so that the gas can flow from the gas channel to the explosion-proof valve, avoiding the problem of blocking the explosion-proof valve gas channel after the battery cell expands and deforms.

Description

Technical Field

[0001] The present invention relates to the field of secondary batteries, and in particular to a top cover structure and a secondary battery. Background Art

[0002] Secondary batteries, also known as rechargeable batteries or storage batteries, are batteries that can be recharged after discharge to reactivate the active materials and continue to be used. In the top cover structure of secondary lithium batteries, the explosion-proof valve plays an outstanding safety role.

[0003] However, when thermal runaway occurs in an existing secondary battery, the battery cell of the secondary battery will expand and deform. The expanded and deformed battery cell will block the gas passage of the explosion-proof valve, rendering the explosion-proof valve ineffective and leading to an explosion accident of the secondary battery. Summary of the Invention

[0004] The embodiments of the present invention provide a top cover structure and a secondary battery, which can improve the problem that when thermal runaway occurs inside the secondary battery, the battery cell expands and deforms to block the gas channel of the explosion-proof valve, rendering the explosion-proof valve ineffective and leading to explosion accidents of the secondary battery.

[0005] In a first aspect, embodiments of the present invention provide a top cover structure for use with a secondary battery. The top cover structure includes a top cover, an explosion-proof valve, a first support member, and a second support member. The top cover is provided with an explosion-proof valve hole. The explosion-proof valve is mounted in the explosion-proof valve hole. The first support member and the second support member are both disposed on the inner side of the top cover, and the first and second support members are located on either side of the explosion-proof valve hole. A gas channel is formed between the first and second support members, and the gas channel is used for gas to flow to the explosion-proof valve.

[0006] In an optional embodiment, the first support member and the second support member are arranged oppositely on two sides of the explosion-proof valve hole.

[0007] In an optional embodiment, the first support member includes a first supporting portion and a first connecting portion connected at an angle, the first connecting portion is connected to the top cover, and the first supporting portion at least partially protrudes from the bottom wall of the top cover;

[0008] The second supporting member includes a second supporting portion and a second connecting portion connected at an angle, the second connecting portion is connected to the top cover, and the second supporting portion at least partially protrudes from the bottom wall of the top cover.

[0009] In an optional embodiment, the number of the first connecting parts includes two, and the two first connecting parts are oppositely arranged on two sides of the first supporting part;

[0010] The number of the second connection parts includes two, and the two second connection parts are oppositely arranged on two sides of the second support part.

[0011] In an optional embodiment, the melting points of the first support member and the second support member are greater than 660°C.

[0012] In an optional embodiment, the first support member and the second support member are both made of metal.

[0013] In an optional embodiment, the first support member and the second support member are both made of stainless steel.

[0014] In an optional embodiment, both the first support member and the second support member are provided with an insulating coating.

[0015] In an optional embodiment, the top cover structure further includes a first insulating cover and a second insulating cover, wherein the first insulating cover is disposed on the first support member, and the second insulating cover is disposed on the second support member.

[0016] In a second aspect, an embodiment of the present invention further provides a secondary battery, comprising the top cover structure described in any one of the above embodiments.

[0017] The advantageous effects of a top cover structure and a secondary battery provided by the embodiments of the present invention include, for example:

[0018] The present application arranges the first support member and the second support member on the inner side of the top cover, and positions the first support member and the second support member on both sides of the explosion-proof valve hole, so that a gas channel is formed between the first support member and the second support member. The gas channel is used for gas to flow to the explosion-proof valve. When thermal runaway occurs inside the secondary battery and the battery cell is deformed, the first support member and the second support member will support the battery cell, thereby keeping the gas channel between the first support member and the second support member unobstructed, so that the gas can flow from the gas channel to the explosion-proof valve, thereby avoiding the problem of blocking the gas channel of the explosion-proof valve after the battery cell expands and deforms. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 A schematic diagram of the overall structure of the top cover structure provided by an embodiment of the present invention;

[0021] Figure 2A schematic diagram of the overall structure of the top cover structure provided by an embodiment of the present invention from another perspective;

[0022] Figure 3 A schematic cross-sectional view of a top cover structure provided by an embodiment of the present invention;

[0023] Figure 4 for Figure 3 A in the middle is an enlarged schematic diagram;

[0024] Figure 5 An exploded schematic diagram of the top cover structure provided by an embodiment of the present invention.

[0025] Icons: 100-top cover structure; 110-top cover; 111-explosion-proof valve hole; 120-gas channel; 130-explosion-proof valve; 150-first support member; 151-first supporting portion; 153-first connecting portion; 155-first mounting portion; 170-second support member; 171-second supporting portion; 173-second connecting portion; 175-second mounting portion; 180-first insulating cover; 181-first bottom wall; 183-first side wall; 190-second insulating cover; 191-second bottom wall; 193-second side wall. DETAILED DESCRIPTION

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0027] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention as claimed, but rather merely represents selected embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without creative effort shall fall within the scope of protection of the present invention.

[0028] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined or explained in subsequent drawings.

[0029] In the description of the present invention, it should be noted that if the terms "upper", "lower", "inside", "outside", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the product of the invention is usually placed when in use. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be understood as a limitation on the present invention.

[0030] In addition, the terms "first", "second", etc., if used, are merely used to distinguish and describe, and should not be understood as indicating or implying relative importance.

[0031] It should be noted that, in the absence of conflict, the features in the embodiments of the present invention may be combined with each other.

[0032] When thermal runaway occurs in an existing secondary battery, the battery cell will swell and deform. The swollen and deformed battery cell will block the gas passage of the explosion-proof valve, rendering the explosion-proof valve ineffective and causing the secondary battery to explode.

[0033] The embodiments of the present invention provide a top cover structure and a secondary battery, which can improve the problem that when thermal runaway occurs inside the secondary battery, the battery cell expands and deforms to block the gas channel of the explosion-proof valve, rendering the explosion-proof valve ineffective and leading to explosion accidents of the secondary battery.

[0034] Please refer to Figure 1 An embodiment of the present invention provides a secondary battery. The secondary battery includes a battery housing (not shown), a battery cell (not shown) mounted in the battery housing, an electrolyte (not shown) filled in the battery housing, and a top cover structure 100 mounted on the battery housing. The top cover structure 100 is provided with positive and negative electrode posts electrically connected to the battery cell.

[0035] Please refer to Figure 1 、 Figure 2 、 Figure 3 and Figure 4 In this embodiment, the top cover structure 100 includes a top cover 110, an explosion-proof valve 130, a first support member 150, and a second support member 170. The top cover 110 is provided with an explosion-proof valve hole 111. The explosion-proof valve 130 is installed in the explosion-proof valve hole 111. The first support member 150 and the second support member 170 are both provided on the inner side of the top cover 110, and the first support member 150 and the second support member 170 are located on both sides of the explosion-proof valve hole 111. A gas channel 120 is formed between the first support member 150 and the second support member 170, and the gas channel 120 is used for gas to flow to the explosion-proof valve 130.

[0036] In this embodiment, the first support member 150 and the second support member 170 are both arranged on the inner side of the top cover 110, and the first support member 150 and the second support member 170 are located on both sides of the explosion-proof valve hole 111, so that a gas channel 120 is formed between the first support member 150 and the second support member 170. The gas channel 120 is used for gas to flow to the explosion-proof valve 130. When thermal runaway occurs inside the secondary battery and the battery cell is deformed, the first support member 150 and the second support member 170 will support the battery cell, so that the gas channel 120 between the first support member 150 and the second support member 170 remains unobstructed, so that gas can flow from the gas channel 120 to the explosion-proof valve 130, thereby avoiding the problem of blocking the gas channel 120 of the explosion-proof valve 130 after the battery cell expands and deforms.

[0037] In this embodiment, the explosion-proof valve 130 can be made of the same metal material as the top cover 110. In this way, the formation of an electrolytic cell with the outside air or electrolyte due to the potential difference between different metals can be overcome, thereby reducing the risk of corrosion reactions. The explosion-proof valve 130 can be made of one of aluminum, aluminum alloy, nickel, nickel alloy, and stainless steel. The explosion-proof valve 130 is provided with a weak line or weak surface. When the internal pressure of the secondary battery is too high, the weak surface or weak line will rupture first, thereby making the rupture position of the explosion-proof valve 130 controllable. The pressure value that the explosion-proof valve 130 can withstand when it reaches the critical state of rupture is approximately 0.3MPa-1.2MPa.

[0038] It should be noted that the inner side of the top cover 110 refers to the side of the top cover 110 located inside the battery case when the top cover 110 is installed in the battery case.

[0039] Please refer to Figure 4 and Figure 5 In this embodiment, the first support member 150 and the second support member 170 are disposed opposite each other on either side of the explosion-proof valve hole 111. This relative positioning of the first support member 150 and the second support member 170 enhances the supporting capacity between the first support member 150 and the second support member 170. Furthermore, a gas channel 120 is formed between the first support member 150 and the second support member 170. When the battery cell expands and deforms and abuts the first and second support members 150 and 170, gas can enter through both ends of the gas channel 120.

[0040] In some other embodiments of the present application, the first support member 150 and the second support member 170 may also be arranged vertically, one of which is arranged in the length direction of the explosion-proof valve 130 , and the other is arranged in the width direction of the explosion-proof valve 130 .

[0041] In this embodiment, to prevent the first support member 150 and the second support member 170 from affecting the air intake permeability of the explosion-proof valve 130, the projections of the first support member 150 and the second support member 170 on the top cover 110 do not overlap with the projection of the explosion-proof valve 130. In other words, the first support member 150 and the second support member 170 are located on the sides of the explosion-proof valve 130.

[0042] In this embodiment, the first support member 150 includes a first support portion 151 and a first connecting portion 153 connected at an angle. The first connecting portion 153 is connected to the top cover 110, and the first support portion 151 at least partially protrudes from the bottom wall of the top cover 110. The second support member 170 includes a second support portion 171 and a second connecting portion 173 connected at an angle. The second connecting portion 173 is connected to the top cover 110, and the second support portion 171 at least partially protrudes from the bottom wall of the top cover 110. The provision of the first connecting portion 153 facilitates the fixing of the first support member 150 to the top cover 110. The provision of the second connecting portion 173 facilitates the fixing of the second support member 170 to the top cover 110.

[0043] Please refer to Figure 4 and Figure 5 In this embodiment, there are two first connecting portions 153, which are disposed oppositely on either side of the first support portion 151. Both first support portions 151 are connected to the top cover 110. The first support portion 151 is parallel to the top cover 110. There are two second connecting portions 173, which are disposed oppositely on either side of the second support portion 171. Both second connecting portions 173 are connected to the top cover 110, and the second support portion 171 is parallel to the top cover 110. Arranging two opposing first connecting portions 153 and two opposing second connecting portions 173 creates an air intake channel between the two first connecting portions 153 and the two second connecting portions 173, thereby minimizing the impact of the first support member 150 and the second support member 170 on the air flow. Having both the first support member 151 and the second support member 171 parallel to the top cover 110 increases the support area of ​​the first support member 150 and the second support member 170, improving the support effect.

[0044] In this embodiment, the first support portion 151 and the first connecting portion 153 are vertically connected, and the second support portion 171 and the second connecting portion 173 are vertically connected. Of course, in other embodiments of the present application, the first support portion 151 and the first connecting portion 153 may be connected at an angle of 30°, 45°, 60°, etc., and the second support portion 171 and the second connecting portion 173 may also be connected at an angle of 30°, 45°, 60°, etc. Secondly, in other embodiments of the present application, the first support member 150 and the second support member 170 may also have an arched structure.

[0045] Please refer to Figure 4 and Figure 5 In this embodiment, both the first support member 150 and the second support member 170 are connected to the top cover 110 via rivets. The first support member 150 further includes a first mounting portion 155 connected at an angle to the first connecting portion 153. The first mounting portion 155 is connected to the top cover 110 via a rivet (not shown). The second support member 170 further includes a second mounting portion 175 connected at an angle to the second connecting portion 173. The second mounting portion 175 is connected to the top cover 110 via a rivet (not shown).

[0046] In this embodiment, the first mounting portion 155 is vertically connected to the first connecting portion 153, and the second mounting portion 175 is vertically connected to the second connecting portion 173. Of course, in other embodiments of the present application, the first mounting portion 155 and the first connecting portion 153 may be connected at an angle of 30°, 45°, 60°, etc., and the second mounting portion 175 and the second connecting portion 173 may also be connected at an angle of 30°, 45°, 60°, etc.

[0047] Of course, in some other embodiments of the present application, the first support member 150 and the second support member 170 can also be installed on the top cover 110 by snapping, gluing, etc.

[0048] In some other embodiments of the present application, the first support member 150 and the second support may also be configured as support blocks, such as metal blocks.

[0049] Please refer to Figure 4 and Figure 5 In this embodiment, the melting points of the first support member 150 and the second support member 170 are greater than 660°C. Since high-temperature gas is generated inside a secondary battery when thermal runaway occurs, the melting points of the first support member 150 and the second support member 170 are set to 660°C, which is the melting point of aluminum. This prevents the first support member 150 and the second support member 170 from melting due to heat, which could lead to support failure, while the battery housing and the top cover 110 are intact.

[0050] In this embodiment, the first support member 150 and the second support member 170 are made of stainless steel. Since stainless steel has strong corrosion resistance, strong bearing capacity and high melting point, it has better supporting effect.

[0051] In some other embodiments of the present application, the first support member 150 may also be made of other metal materials, such as nickel, or high-temperature resistant non-metal, such as ceramic.

[0052] Please refer to Figure 4 and Figure 5 In this embodiment, the top cover structure 100 further includes a first insulating cover 180 and a second insulating cover 190. The first insulating cover 180 is disposed on the first support member 150, and the second insulating cover 190 is disposed on the second support member 170. The provision of the first insulating cover 180 and the second insulating cover 190 can prevent the metal first support member 150 and the second support member 170 from causing a short circuit in the battery cell.

[0053] In this embodiment, the first insulating cover 180 is mounted on the first support member 150 via a snap-fit ​​structure, and the second insulating cover 190 is mounted on the second support member 170 via a snap-fit ​​structure. Of course, in other embodiments of the present application, the first insulating cover 180 can also be mounted on the first support member 150 and the second support member 170 by gluing, screwing, or the like.

[0054] In this embodiment, the first insulating cover 180 includes a first bottom wall 181 and a first side wall 183 connected at an angle. The first bottom wall 181 is mounted outside the first support portion 151 to insulate the first support portion 151. The first side wall 183 surrounds the side of the first support member 150 away from the second support member 170 to insulate the first connecting portion 153 from the first mounting portion 155. The second insulating cover 190 includes a second bottom wall 191 and a second side wall 193 connected at an angle. When the second insulating cover 190 is mounted on the second support member 170, the second bottom wall 191 is mounted outside the second support portion 171 to insulate the second support portion 171. The second side wall 193 surrounds the side of the second support member 170 away from the first support member 150 to insulate the second mounting portion 175 and the second connecting portion 173. This prevents the first and second support members 150 and 170 from contacting the battery cells, positive and negative electrodes, and causing short circuits.

[0055] Of course, in some other embodiments of the present application, both the first support member 150 and the second support member 170 may be provided with an insulating coating. The insulating coating may be sprayed with Teflon, epoxy resin, phenolic resin, polyethylene terephthalate, polypropylene, ceramic, or other coating to insulate the first support member 150 and the second support member 170.

[0056] The working principle and beneficial effects of a top cover structure 100 and a secondary battery provided by an embodiment of the present invention include:

[0057] In the present application, the first support member 150 and the second support member 170 are both arranged on the inner side of the top cover 110, and the first support member 150 and the second support member 170 are located on both sides of the explosion-proof valve hole 111, so that a gas channel 120 is formed between the first support member 150 and the second support member 170. The gas channel 120 is used for gas to flow to the explosion-proof valve 130. When thermal runaway occurs inside the secondary battery and the battery cell is deformed, the first support member 150 and the second support member 170 will support the battery cell, so that the gas channel 120 between the first support member 150 and the second support member 170 remains unobstructed, so that the gas can flow from the gas channel 120 to the explosion-proof valve 130, thereby avoiding the problem of blocking the gas channel 120 of the explosion-proof valve 130 after the battery cell expands and deforms.

[0058] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A top cover structure, applied to a secondary battery, characterized in that: include: A top cover (110), wherein the top cover (110) is provided with an explosion-proof valve hole (111); An explosion-proof valve (130), the explosion-proof valve (130) being installed in the explosion-proof valve hole (111); a first support member (150) and a second support member (170), wherein the first support member (150) and the second support member (170) are both arranged on the inner side of the top cover (110), and the first support member (150) and the second support member (170) are located on both sides of the explosion-proof valve hole (111); when thermal runaway occurs inside the secondary battery and the battery cell is deformed, the first support member (150) and the second support member (170) are used to support the battery cell, thereby forming a gas channel (120) between the first support member (150) and the second support member (170), and the gas channel (120) is used for gas to flow to the explosion-proof valve (130); The first support member (150) includes a first support portion (151) and a first connection portion (153) connected at an angle, the second support member (170) includes a second support portion (171) and a second connection portion (173) connected at an angle, the first connection portion (153) is connected to the top cover (110), the first support portion (151) at least partially protrudes from the bottom wall of the top cover (110), the second connection portion (173) is connected to the top cover (110), and the second support portion (171) at least partially protrudes from the bottom wall of the top cover (110); The number of the first connecting parts (153) includes two, and the two first connecting parts (153) are arranged oppositely on two sides of the first supporting part (151); The number of the second connecting parts (173) includes two, and the two second connecting parts (173) are arranged oppositely on two sides of the second supporting part (171); An air intake channel is formed between the two first connecting parts (153) and between the two second connecting parts (173); The first support member (150) and the second support member (170) are both made of metal; The first support member (150) and the second support member (170) are both provided with an insulating coating; or the top cover structure (100) further comprises a first insulating cover (180) and a second insulating cover (190), wherein the first insulating cover (180) is provided on the first support member (150) and the second insulating cover (190) is provided on the second support member (170).

2. The top cover structure according to claim 1, characterized in that: The first support member (150) and the second support member (170) are arranged oppositely on two sides of the explosion-proof valve hole (111).

3. The roof structure according to claim 1 or 2, characterized in that: The melting points of the first support member (150) and the second support member (170) are greater than 660°C.

4. The top cover structure according to claim 1, characterized in that: The first support member (150) and the second support member (170) are both made of stainless steel.

5. A secondary battery, characterized in that: The invention comprises a top cover structure (100) according to any one of claims 1 to 4.

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