Battery cover plate and battery

Abstract

The utility model relates to the technical field of power batteries, and particularly discloses a battery cover plate and a battery. Wherein the battery cover plate covers an opening of the battery shell, and a pole group is arranged in the battery shell. The battery cover plate comprises a light aluminum plate, lower plastic and a limiting bracket. Wherein the light aluminum plate is provided with an anti-explosion valve; the lower plastic is connected with the light aluminum plate; and the limiting bracket is arranged between the light aluminum plate and the lower plastic. And the limiting bracket is configured to be abutted between the light aluminum plate and the pole group under the condition that the plastic is melted due to thermal runaway of the battery, so that an exhaust channel communicated with the ventilation port of the explosion-proof valve is formed between the light aluminum plate and the pole group. According to the scheme, the pole group is prevented from blocking the explosion-proof valve under the impact extrusion of airflow, adverse consequences caused by thermal runaway of the battery are relieved, and the safety performance of the battery is improved. In addition, the battery comprises the battery cover plate, so that the battery has all the beneficial effects of the battery cover plate.

Description

Technical Field

[0001] The utility model relates to the technical field of power batteries, and in particular to a battery cover and a battery. Background Art

[0002] At present, with the increasing maturity of lithium-ion battery technology, lithium-ion batteries have been widely used as power batteries in the field of electric vehicles. Therefore, people's requirements for the safety performance of lithium-ion batteries are increasing.

[0003] In the traditional lithium-ion battery structure, the cover plate and the shell are welded to encapsulate the electrode group inside the shell; the lower plastic of the cover plate presses against the electrode group to limit the electrode group. However, when the battery has thermal runaway, the internal temperature of the battery increases, and the gas generation increases, causing the explosion-proof valve to automatically open for exhaust; at this time, the lower plastic may melt at high temperature, thereby losing the limiting effect on the electrode group, and the electrode group may block the explosion-proof valve under the impact of the airflow, aggravating the battery runaway and posing a greater safety risk. Utility Model Content

[0004] In view of this, the utility model provides a battery cover and a battery to solve the existing problem that when thermal runaway occurs in the battery, the pole group may block the explosion-proof valve under the impact of airflow, aggravating the battery runaway and posing a greater safety risk.

[0005] In the first aspect, the utility model provides a battery cover, which is arranged on the opening of the battery shell, and a pole group is arranged inside the battery shell. Furthermore, the battery cover includes a plain aluminum plate, a lower plastic and a limit bracket. Among them, the plain aluminum plate is provided with an explosion-proof valve; the lower plastic is connected to the plain aluminum plate; and the limit bracket is arranged between the plain aluminum plate and the lower plastic. The limit bracket is configured as follows: in the case where the thermal runaway of the battery causes the lower plastic to melt, the limit bracket abuts between the plain aluminum plate and the pole group, so that an exhaust channel connected to the air vent of the explosion-proof valve is formed between the plain aluminum plate and the pole group.

[0006] In an optional implementation, the lower plastic is provided with a receiving cavity, and the limiting bracket is provided in the receiving cavity.

[0007] In an optional embodiment, the accommodating chamber corresponds to the position of the explosion-proof valve; the wall surface of the accommodating chamber and the limiting bracket are respectively provided with ventilation holes passing through each other, and the ventilation holes of the two are arranged correspondingly, and the ventilation holes connect the interior of the battery shell and the accommodating chamber.

[0008] In an optional embodiment, the limiting bracket is integrally connected to the lower plastic accommodating cavity by injection molding; and / or, the limiting bracket is provided with a plurality of limiting holes, and the inner wall of the accommodating cavity is provided with an injection molding protrusion, and the injection molding protrusion is clamped in the limiting hole.

[0009] In an optional implementation, there is a gap between the limiting bracket and the bare aluminum plate.

[0010] In an optional implementation, the extension distance of the limiting bracket in the width direction of the lower plastic is greater than the width of the air vent of the explosion-proof valve.

[0011] In an optional embodiment, both ends of the exhaust channel are inlets, the middle of the exhaust channel is connected to the explosion-proof valve vent, and the sum of the cross-sectional areas of the two inlets is greater than or equal to the vent area.

[0012] In an optional implementation, the limiting bracket is made of a high temperature resistant and corrosion resistant material.

[0013] In an optional embodiment, there are multiple limiting brackets, and the multiple limiting brackets are arranged at intervals along the length direction of the lower plastic.

[0014] In a second aspect, the utility model further provides a battery, comprising a battery housing, a pole group disposed inside the battery housing, and the battery cover in the first aspect, wherein the battery cover covers an opening of the battery housing.

[0015] Beneficial effects: In the battery cover of the first aspect, a limiting bracket is added between the bare aluminum sheet and the lower plastic. When the battery thermal runaway causes the lower plastic to melt, the limiting bracket abuts between the bare aluminum sheet and the pole group, so that the bare aluminum sheet and the pole group form an exhaust channel connected to the air vent of the explosion-proof valve, preventing the pole group from blocking the explosion-proof valve under the impact of the airflow, alleviating the adverse consequences of battery thermal runaway, and increasing the safety performance of the battery. In addition, the battery of the second aspect includes the battery cover of the first aspect, so the battery of the second aspect has all the beneficial effects of the battery cover of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0017] Figure 1 This is an exploded view of the battery cover according to an embodiment of the utility model;

[0018] Figure 2 A top view of a battery according to an embodiment of the utility model;

[0019] Figure 3 for Figure 2 Cross-sectional view at AA in the middle;

[0020] Figure 4 for Figure 3A magnified schematic diagram of point B in the middle.

[0021] Description of reference numerals:

[0022] 100. Battery;

[0023] 110, battery cover; 120, battery housing; 130, electrode group;

[0024] 111. Plain aluminum plate; 112. Lower plastic; 113. Limit bracket;

[0025] 1111, explosion-proof valve;

[0026] 1121, accommodating cavity; 1122, vent hole; 1123, injection molding protrusion;

[0027] 1131. Bottom plate; 1132. Side plate; 1133. Limiting hole. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.

[0029] In order to deepen the understanding of the solution of the utility model, it is necessary to elaborate on the technical problems in detail in combination with relevant technologies. The specific contents are as follows:

[0030] In the traditional lithium-ion battery structure, the cover plate and the shell are welded to encapsulate the electrode group inside the shell; the lower plastic of the cover plate presses against the electrode group to limit the electrode group. However, when the battery has thermal runaway, the internal temperature of the battery increases, and the gas generation increases, causing the explosion-proof valve to automatically open for exhaust; at this time, the lower plastic may melt at high temperature, thereby losing the limiting effect on the electrode group, and the electrode group may block the explosion-proof valve under the impact of the airflow, aggravating the battery runaway and posing a greater safety risk.

[0031] Furthermore, the battery temperature is generally controlled by a dedicated temperature control circuit. When the temperature control circuit fails, the battery may suffer thermal runaway, the chemical reaction inside the battery will intensify, and more gas will be generated. If the high temperature melts the plastic at this time, and the electrode group blocks the vent of the explosion-proof valve, the battery will be in danger of exploding.

[0032] In order to alleviate the above technical problems, the utility model provides a battery cover and a battery. Figures 1 to 4The embodiments of the present utility model are described in detail.

[0033] First, refer to Figure 1 and Figure 4 The utility model provides a battery cover 110, which is covered on the opening of the battery housing 120, and a pole group 130 is arranged inside the battery housing 120. Furthermore, the battery cover 110 includes a plain aluminum plate 111, a lower plastic 112 and a limit bracket 113. Among them, the plain aluminum plate 111 is provided with an explosion-proof valve 1111; the lower plastic 112 is connected to the plain aluminum plate 111; and the limit bracket 113 is arranged between the plain aluminum plate 111 and the lower plastic 112. The limit bracket 113 is configured as follows: when the battery 100 thermal runaway causes the lower plastic 112 to melt, the limit bracket 113 abuts between the plain aluminum plate 111 and the pole group 130, so that an exhaust channel connected to the air vent of the explosion-proof valve 1111 is formed between the plain aluminum plate 111 and the pole group 130.

[0034] Specifically, the battery cover 110 of the present solution is additionally provided with a limiting bracket 113 between the bare aluminum sheet and the lower plastic 112. When the battery 100 thermally runs away and causes the lower plastic 112 to melt, the limiting bracket 113 abuts between the bare aluminum plate 111 and the electrode group 130, so that an exhaust channel connected to the air vent of the explosion-proof valve 1111 is formed between the bare aluminum plate 111 and the electrode group 130, thereby preventing the electrode group 130 from clogging the explosion-proof valve 1111 under the impact of the air flow, alleviating the adverse consequences brought about by the thermal runaway of the battery 100, and increasing the safety performance of the battery 100.

[0035] In some embodiments, reference Figure 1 The lower plastic 112 defines a receiving cavity 1121 , and the limiting bracket 113 is disposed in the receiving cavity 1121 .

[0036] Specifically, the limiting bracket 113 is received in the accommodating cavity 1121 of the lower plastic 112 , which reduces the extra space occupied by the limiting bracket 113 inside the battery housing 120 and has little impact on the volume of the battery 100 .

[0037] More specifically, the limiting bracket 113 includes a bottom plate 1131 and side plates 1132 respectively connected to the corners at both ends of the bottom plate 1131, the bottom plate 1131 is attached to the bottom wall of the accommodating cavity 1121, and the side plates 1132 are attached to the side walls of the accommodating cavity 1121; the outer side of the bottom wall of the accommodating cavity 1121 abuts against the pole group 130 to limit the pole group 130.

[0038] In particular, when the battery 100 is subjected to external impact, the lower plastic 112 is a soft material and will vibrate; the limiting bracket 113 is arranged in the accommodating cavity 1121 of the lower plastic 112, which can increase the strength of the lower plastic 112 to reduce the deformation of the lower plastic 112.

[0039] In some embodiments, reference Figure 3 and Figure 4 The accommodating chamber 1121 corresponds to the explosion-proof valve 1111 ; the wall surface of the accommodating chamber 1121 and the limiting bracket 113 are respectively provided with ventilation holes 1122 penetrating therethrough, and the ventilation holes 1122 of the two are arranged correspondingly, and the ventilation holes 1122 connect the interior of the battery shell 120 with the accommodating chamber 1121 .

[0040] Specifically, in this solution, the limit bracket 113 is arranged at a position corresponding to the explosion-proof valve 1111, so that the flow diameter of the exhaust channel is maximized, which is convenient for exhausting through the exhaust channel after the lower plastic 112 melts due to thermal runaway; in addition, a vent hole 1122 is provided that passes through the limit bracket 113 and the wall of the accommodating chamber 1121, and the vent hole 1122 connects the interior of the battery shell 120 with the accommodating chamber 1121. The position of the accommodating chamber 1121 corresponds to the explosion-proof valve 1111, which can solve the exhaust problem under normal conditions.

[0041] More specifically, the vent hole 1122 can be, but is not limited to, a strip hole, a waist hole, an elliptical hole, etc., and the vent hole 1122 has a relatively large flow diameter. Preferably, there are multiple vent holes 1122, which penetrate the bottom wall of the accommodating cavity 1121 and the bottom plate 1131 of the limiting bracket 113.

[0042] In some embodiments, reference Figure 1 , the limiting bracket 113 is integrally connected with the lower plastic 112 accommodating cavity 1121 by injection molding; and / or, the limiting bracket 113 is provided with a plurality of limiting holes 1133 , and the inner wall of the accommodating cavity 1121 is provided with an injection molding protrusion 1123 , and the injection molding protrusion 1123 is clamped in the limiting hole 1133 .

[0043] Specifically, the limiting bracket 113 is integrally connected with the lower plastic 112 accommodating cavity 1121 by injection molding, and the structure is stable; and the limiting bracket 113 is provided with a plurality of limiting holes 1133. During injection molding, the lower plastic 112 flows into the limiting holes 1133 and solidifies, further increasing the stability of the connection between the two.

[0044] Preferably, the limiting holes 1133 are provided on the bottom plate 1131 and the side plate 1132 of the limiting bracket 113 and are evenly distributed, so that the lower plastic 112 and the limiting bracket 113 are firmly connected at all locations.

[0045] In particular, “and / or” means that the options preceding “and / or” and the options following “and / or” are set alternatively or simultaneously.

[0046] In some embodiments, reference Figure 4 There is a gap between the limiting bracket 113 and the bare aluminum plate 111.

[0047] Specifically, the limiting bracket 113 does not contact the aluminum plate 111 , so as to prevent the limiting bracket 113 from being scratched against the aluminum plate 111 , thereby preventing metal chips from falling and causing an internal short circuit in the battery 100 .

[0048] Furthermore, the limiting bracket 113 may be made of metal, and the metal shavings may belong to the limiting bracket 113 or the bare aluminum plate 111 .

[0049] More specifically, the depth of the accommodating cavity 1121 is greater than the height of the limiting bracket 113, and the limiting bracket 113 is arranged close to the bottom of the accommodating cavity 1121 to ensure that there is a gap between the limiting bracket 113 and the bare aluminum plate 111. For ease of understanding, it is further explained that the height of the limiting bracket 113 is the height of the side plate 1132, and there is a gap between the end of the side plate 1132 facing the bare aluminum plate 111 and the inner side of the bare aluminum plate 111.

[0050] In some embodiments, reference Figure 1 The extension distance of the limiting bracket 113 in the width direction of the lower plastic 112 is greater than the width of the air vent of the explosion-proof valve 1111.

[0051] Specifically, the extension distance of the limiting bracket 113 in the width direction of the lower plastic 112 is greater than the width of the air vent of the explosion-proof valve 1111, so as to prevent the limiting bracket 113 from being rushed out of the explosion-proof valve 1111 by the airflow inside the battery housing 120 after the lower plastic 112 melts due to thermal runaway.

[0052] In some embodiments, both ends of the exhaust channel are inlets, the middle of the exhaust channel is connected to the air vent of the explosion-proof valve 1111, and the sum of the cross-sectional areas of the two inlets is greater than the air vent area.

[0053] Specifically, in this solution, the sum of the cross-sectional areas of the inlets at both ends of the exhaust channel is greater than or equal to the air vent area, so that the exhaust rate is not affected and the exhaust can be normal.

[0054] More specifically, the bottom plate 1131 of the limiting bracket 113 extends along the width direction of the lower plastic 112, and the two ends of the bottom plate 1131 are connected to the side plates 1132; after the lower plastic 112 melts due to thermal runaway, the side plates 1132 abut against the bare aluminum plate 111 and form an exhaust channel, which extends along the length direction of the bare aluminum plate 111. The cross-sectional area of ​​the inlet of the exhaust channel mainly depends on the height of the limiting bracket 113. Preferably, the height of the limiting bracket 113 is greater than 3 mm; in addition, the thickness of the limiting bracket 113 is not less than 0.3 mm, ensuring that the limiting bracket 113 will not be plastically deformed under the stamping of the pole group 130.

[0055] In some embodiments, the limiting bracket 113 is made of a high temperature resistant and corrosion resistant material.

[0056] Specifically, the limiting bracket 113 needs to ensure that it is not easy to melt under thermal runaway and does not react with the electrolyte inside the battery 100.

[0057] Preferably, the limiting bracket 113 is made of metal materials such as aluminum, copper, stainless steel, or ceramics.

[0058] In some embodiments, there are multiple limiting brackets 113 , and the multiple limiting brackets 113 are arranged at intervals along the length direction of the lower plastic 112 .

[0059] Specifically, the limit bracket 113 can also be set at a position with an offset distance from the explosion-proof valve 1111, and it does not have to correspond to the explosion-proof valve 1111, as long as it is ensured that when thermal runaway occurs, the limit bracket 113 forms an exhaust channel between the bare aluminum plate 111 and the electrode group 130 to prevent the electrode group 130 from blocking the explosion-proof valve 1111; moreover, multiple limit brackets can be set to enhance the structural strength, as long as it does not affect other structural designs of the battery 100. In particular, the above solutions all fall within the protection scope of the present utility model.

[0060] Secondly, refer to Figure 2 and Figure 3 The utility model further provides a battery 100 , which includes a battery housing 120 , an electrode group 130 disposed inside the battery housing 120 , and a battery cover 110 , wherein the battery cover 110 covers an opening of the battery housing 120 .

[0061] In particular, the battery 100 in this solution includes a battery cover 110, so the battery 100 provided by this solution has all the beneficial effects of the battery cover 110. In addition, the battery 100 of this solution also includes other components such as a battery protection board, and only the components related to this solution are listed here, but the composition of the battery 100 is not limited.

[0062] Although the embodiments of the present invention are described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A battery cover plate, covering an opening of a battery housing, wherein a pole group is arranged inside the battery housing, characterized in that: The battery cover comprises: A plain aluminum plate, wherein the plain aluminum plate is provided with an explosion-proof valve; A lower plastic, wherein the lower plastic is connected to the bare aluminum plate; A limit bracket is provided between the bare aluminum plate and the lower plastic; the limit bracket is configured such that when the battery thermal runaway causes the lower plastic to melt, the limit bracket abuts between the bare aluminum plate and the electrode group, so that an exhaust channel connected to the air vent of the explosion-proof valve is formed between the bare aluminum plate and the electrode group.

2. The battery cover according to claim 1, characterized in that: The lower plastic is provided with a receiving cavity, and the limiting bracket is arranged in the receiving cavity.

3. The battery cover according to claim 2, characterized in that: The accommodating cavity corresponds to the position of the explosion-proof valve; The wall surface of the accommodating cavity and the limiting bracket are respectively provided with ventilation holes penetrating therethrough, and the ventilation holes of the two are arranged correspondingly, and the ventilation holes communicate with the interior of the battery shell and the accommodating cavity.

4. The battery cover according to claim 2, characterized in that: The limiting bracket is integrally connected to the lower plastic accommodating cavity by injection molding; And / or, the limiting bracket is provided with a plurality of limiting holes, the inner wall of the accommodating cavity is provided with an injection-molded protrusion, and the injection-molded protrusion is clamped in the limiting hole.

5. The battery cover according to claim 2, characterized in that: There is a gap between the limiting bracket and the bare aluminum plate.

6. The battery cover according to claim 1, characterized in that: The extension distance of the limiting bracket in the width direction of the lower plastic is greater than the width of the air vent of the explosion-proof valve.

7. The battery cover according to claim 1, characterized in that: Both ends of the exhaust channel are inlets respectively, the middle of the exhaust channel is connected to the explosion-proof valve air vent, and the sum of the cross-sectional areas of the two inlets is greater than or equal to the air vent area.

8. The battery cover according to claim 1, characterized in that: The limiting bracket is made of high temperature resistant and corrosion resistant material.

9. The battery cover according to claim 1, characterized in that: There are a plurality of the limiting brackets, and the plurality of the limiting brackets are arranged at intervals along the length direction of the lower plastic.

10. A battery, characterized in that: The invention comprises a battery housing, a pole group arranged inside the battery housing, and a battery cover according to any one of claims 1 to 9, wherein the battery cover is arranged to cover an opening of the battery housing.

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