Battery cover plate and battery
By introducing limiting parts and high-temperature resistant materials into the lithium-ion battery cover, the exhaust passage is formed, which solves the problem of the pole group blocking the explosion-proof valve when the lithium-ion battery is thermally out of control, and improves the safety performance of the battery.
Patent Information
- Application Number
- CN202323270464.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-11-30
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2033-11-30
AI Technical Summary
When a lithium-ion battery has thermal runaway, the lower plastic plate may melt, causing the electrode group to block the explosion-proof valve, increasing the safety risk of the battery to lose control.
Design a battery cover plate, including a light aluminum plate, a lower plastic plate and a limiting part. When the lower plastic plate melts, the limiting part abuts between the light aluminum plate and the electrode group to form an exhaust passage to prevent the electrode group from blocking the explosion-proof valve. And the structure is enhanced through multiple inlet ports and electrolyte-resistant and high-temperature colloidal materials.
It effectively prevents the pole group from blocking the explosion-proof valve under the airflow, alleviates the adverse consequences of battery thermal runaway, increases the safety performance of the battery, and has little impact on the overall volume of the battery, and does not affect the design of other components.
Smart Images
Figure CN222261226U_ABST
Abstract
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 plate of the cover plate is against the electrode group, which plays the role of limiting 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 plate 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 housing, and the battery housing is provided with a pole group inside, and the battery cover includes a plain aluminum plate, a lower plastic plate and a stopper. Among them, the plain aluminum plate is provided with an explosion-proof valve; the lower plastic plate is connected to the plain aluminum plate, and the lower plastic plate is provided with a receiving cavity; the stopper is arranged in the receiving cavity, and the stopper is suitable for abutting between the plain aluminum plate and the pole group when the lower plastic plate melts due to thermal runaway of the battery, 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 embodiment, the exhaust passage has a plurality of inlets, and the sum of the areas of the plurality of inlets is greater than or equal to the area of the air vent of the explosion-proof valve.
[0007] In an optional implementation, the length of the limiting member is greater than the maximum inner diameter of the air vent of the explosion-proof valve.
[0008] In an optional embodiment, a gap exists between a side of the accommodating cavity close to the pole group and the pole group.
[0009] In an optional implementation, the limiting member is a colloid that is resistant to electrolyte and high temperature, and the limiting member is injection-molded in the accommodating cavity.
[0010] In an optional embodiment, the width of the accommodating cavity is not less than 2 mm.
[0011] In an optional embodiment, the opening of the accommodating cavity is arranged on the side facing the plain aluminum plate.
[0012] In an optional implementation, the lower plastic plate is provided with a plurality of accommodating cavities, and the plurality of limiting members are provided in a one-to-one correspondence in the plurality of accommodating cavities.
[0013] In an optional implementation, pole ears are respectively provided at both ends of the pole group, and accommodating cavities located outside the pole ears are respectively provided at both ends of the lower plastic plate.
[0014] In a second aspect, the utility model further provides a battery, comprising a battery housing, an electrode 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 stopper is added between the bare aluminum sheet and the lower plastic plate. When the battery thermal runaway causes the lower plastic plate to melt, the stopper 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 air flow, 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] Description of reference numerals:
[0021] 100. Battery;
[0022] 110, battery cover; 120, battery housing; 130, electrode group;
[0023] 111. Plain aluminum plate; 112. Lower plastic plate; 113. Limiting piece;
[0024] 1111, explosion-proof valve;
[0025] 1121, accommodating chamber;
[0026] 131. Extreme ears. DETAILED DESCRIPTION
[0027] 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.
[0028] 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:
[0029] 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 plate of the cover plate is against the electrode group, which plays the role of limiting 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 plate 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.
[0030] Furthermore, the battery temperature is generally controlled by a special 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 lower plastic plate at this time, and the electrode group blocks the vent of the explosion-proof valve, the battery will be in danger of exploding.
[0031] In order to alleviate the above technical problems, the utility model provides a battery cover and a battery. Figures 1 to 3 The embodiments of the present utility model are described in detail.
[0032] First, refer to Figure 1 and Figure 3The utility model provides a battery cover 110, which is covered on the opening of the battery housing 120, and the battery housing 120 is provided with a pole group 130. The battery cover 110 includes a plain aluminum plate 111, a lower plastic plate 112 and a stopper 113. The plain aluminum plate 111 is provided with an explosion-proof valve 1111; the lower plastic plate 112 is connected to the plain aluminum plate 111, and the lower plastic plate 112 is provided with a receiving cavity 1121; the stopper 113 is provided in the receiving cavity 1121, and the stopper 113 is suitable for abutting between the plain aluminum plate 111 and the pole group 130 when the lower plastic plate 112 melts due to thermal runaway of the battery 100, 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.
[0033] Specifically, a limit member 113 is added between the bare aluminum sheet and the lower plastic plate 112. When the battery 100 thermally runs away and causes the lower plastic plate 112 to melt, the limit member 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 airflow, alleviating the adverse consequences brought about by the thermal runaway of the battery 100, and increasing the safety performance of the battery 100.
[0034] More specifically, the limiting member 113 is accommodated in the accommodating cavity 1121 of the lower plastic plate 112, thereby reducing the additional space occupied by the limiting member 113 inside the battery housing 120 and having little impact on the overall volume of the battery 100; moreover, the accommodating cavity 1121 wraps and limits the limiting member 113 to prevent the limiting member 113 from moving inside the battery housing 120 and damaging the electrode group 130.
[0035] Furthermore, the lower plastic plate 112 is made of soft material, and when the battery 100 is subjected to external impact, the lower plastic plate 112 will deform; the limiting member 113 is arranged in the accommodating cavity 1121 of the lower plastic plate 112, which can increase the strength of the lower plastic plate 112 to reduce the deformation of the lower plastic plate 112.
[0036] In some embodiments, reference Figure 1 and Figure 3 The exhaust passage has a plurality of inlets, and the sum of the areas of the plurality of inlets is greater than or equal to the area of the air vent of the explosion-proof valve 1111.
[0037] Specifically, in this solution, the sum of the areas of the multiple inlets is greater than or equal to the area of the air vent of the explosion-proof valve 1111, so that the exhaust rate is not affected and the exhaust can be normal.
[0038] More specifically, the limit member 113 is preferably a block structure. After the battery 100 thermal runaway causes the lower plastic plate 112 to melt, the limit member 113 is supported between the bare aluminum plate 111 and the electrode group 130 to form an exhaust channel. The gas generated inside the battery shell 120 enters the exhaust channel from the inlet. The gas flow directions at different inlets are different, but they all converge at the explosion-proof valve 1111 and then are discharged from the battery shell 120 from the explosion-proof valve 1111.
[0039] Preferably, the exhaust channel extends along the length direction of the bare aluminum plate 111, the middle of the exhaust channel is connected to the air vent when the explosion-proof valve 1111 is opened, and the two ends of the exhaust channel in the length direction are the main inlets, so the inlet area mainly depends on the height of the limiter 113.
[0040] More preferably, the height of the limiting member 113 is greater than or equal to 3 mm.
[0041] In some embodiments, reference Figure 1 The length of the limiting member 113 is greater than the maximum inner diameter of the air vent of the explosion-proof valve 1111.
[0042] Specifically, the length of the limiter 113 is greater than the maximum inner diameter of the vent of the explosion-proof valve 1111 to prevent the limiter 113 from being flushed out of the explosion-proof valve 1111 by the airflow inside the battery housing 120 after the lower plastic plate 112 melts due to thermal runaway of the battery 100.
[0043] More specifically, the air vent of the explosion-proof valve 1111 can be a circular hole, a waist-shaped hole, etc., or an irregularly shaped opening; the length of the longest line segment connecting the inner edges of the air vent is less than the length of the limiter 113.
[0044] In some embodiments, reference Figure 3 There is a gap between the side of the accommodating cavity 1121 close to the electrode group 130 and the electrode group 130 .
[0045] Specifically, a gap is formed between the side of the accommodating cavity 1121 close to the electrode group 130 and the electrode group 130 to prevent the electrode group 130 from being crushed.
[0046] In particular, the lower plastic plate 112 is made of soft material, and the side wall of the accommodating cavity 1121 close to the pole group 130 slightly presses the pole group 130, while ensuring that the compression deformation of the accommodating cavity 1121 is not greater than 2 mm. This solution can also prevent the pole group 130 from being crushed, and is also within the protection scope of this patent.
[0047] It should be noted that the distance between the lower plastic plate 112 and the electrode assembly 130 excluding the accommodating cavity 1121 is the same as above, that is, the lower plastic plate 112 can maintain a gap with the electrode assembly 130 or slightly press the electrode assembly 130 .
[0048] In some embodiments, reference Figure 1 and Figure 3 The limiting member 113 is a colloid that is resistant to electrolyte and high temperature, and the limiting member 113 is injection molded in the accommodating cavity 1121 .
[0049] Specifically, the limiter 113 is a colloid that is resistant to electrolyte and high temperature. It is not easy to melt when the battery 100 is in thermal runaway, and does not react with the electrolyte inside the battery 100. In addition, the colloid is not conductive, so there is no need to worry about the limiter 113 itself dropping conductive debris and causing an internal short circuit in the battery 100. It can also avoid the limiter 113 contacting the electrode group 130 and causing an internal short circuit in the battery 100.
[0050] Furthermore, the limiting member 113 is injection molded in the accommodating cavity 1121 , and the limiting member 113 is firmly connected to the lower plastic member and is not easy to move, and is easy to manufacture and can be formed quickly.
[0051] Preferably, the limiting member 113 is epoxy resin glue, which is injected into the accommodating cavity 1121 and dried in a baking oven at about 85°C to accelerate the molding of the limiting member 113; in addition, the lower plastic plate 112 is preferably made of PP (Polypropylene) material with a melting point of 160°C, so when the limiting member 113 is dried and molded, the lower plastic plate 112 will not melt.
[0052] In particular, the limit member 113 can also be made of metal materials such as aluminum, copper, stainless steel, or ceramics, and can also meet the requirements of electrolyte resistance and high temperature resistance. The above embodiments are all within the scope of protection of this patent.
[0053] In some embodiments, reference Figure 1 , the width of the accommodating cavity 1121 is not less than 2 mm.
[0054] Specifically, the width of the accommodating cavity 1121 is not less than 2 mm, so as to ensure that when the accommodating cavity 1121 is injected with glue, the glue has good fluidity and is formed evenly.
[0055] Furthermore, the width of the accommodating cavity 1121 is relatively large, and the colloid after molding is relatively wide and has a certain strength, thereby ensuring that the limiting member 113 will not generate plastic deformation under the stamping of the electrode group 130 .
[0056] In some embodiments, referring to the figure, the opening of the accommodating cavity 1121 is arranged on a side facing the bare aluminum plate 111 .
[0057] Specifically, the opening of the accommodating cavity 1121 is arranged on the side facing the bare aluminum plate 111 , which is convenient for glue injection and not easy to flow out, and it is easy to control the depth of glue injection, thereby controlling the height of the limiter 113 .
[0058] Preferably, the accommodating cavity 1121 is a strip-shaped cavity and extends along the width direction of the lower plastic plate 112. The opening of the accommodating cavity 1121 is as long as the cavity to facilitate glue injection. When injecting glue, the depth of the glue is less than the depth of the accommodating cavity 1121 to prevent glue overflow.
[0059] In particular, the accommodating cavity 1121 may also be in other shapes, such as a semicircle or semipolygon with the flat end facing downward, as long as the maximum length, maximum width and maximum depth meet the requirements. In addition, the opening of the accommodating cavity 1121 may also be provided at one of the front and rear sides of the lower plastic plate 112, and the orientation of the lower plastic plate 112 needs to be changed during the injection of the glue so that the opening faces upward. The above solutions are all within the scope of protection of this patent.
[0060] In some embodiments, reference Figure 1 The lower plastic plate 112 is provided with a plurality of accommodating cavities 1121 , and the limiting members 113 have a plurality of accommodating cavities 1121 , and the plurality of limiting members 113 are arranged in the plurality of accommodating cavities 1121 in a one-to-one correspondence.
[0061] Specifically, this solution can make the flow cross-section of the exhaust passage uniform after the battery 100 thermally runs away, and further increase the overall structural strength.
[0062] More specifically, the accommodating cavity 1121 and the limiting member 113 do not affect the structural design of other components of the battery 100 .
[0063] In some embodiments, reference Figure 1 and Figure 3 Both ends of the electrode group 130 are provided with electrode ears 131 , and both ends of the lower plastic plate 112 are provided with accommodation cavities 1121 located outside the electrode ears 131 .
[0064] Specifically, after the thermal runaway of the battery 100 causes the lower plastic plate 112 to melt, the tab 131 has a blocking effect on the limiting member 113 to prevent the limiting member 113 from being impacted by the airflow and moving.
[0065] Secondly, refer to Figure 2 and Figure 3 The utility model further provides a battery 100 , including 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 .
[0066] Specifically, the battery 100 in this solution includes a battery cover 110, so the battery 100 has all the beneficial effects of the battery cover 110. In addition, the battery 100 in 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.
[0067] 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 plate, the lower plastic plate is connected to the bare aluminum plate, and the lower plastic plate is provided with a receiving cavity; A limit member is arranged in the accommodating cavity, and the limit member is suitable for abutting between the bare aluminum plate and the electrode group when the battery thermal runaway causes the lower plastic plate to melt, 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 exhaust passage has a plurality of inlets, and the sum of the areas of the plurality of inlets is greater than or equal to the area of the air vent of the explosion-proof valve.
3. The battery cover according to claim 1, characterized in that: The length of the limiting member is greater than the maximum inner diameter of the air vent of the explosion-proof valve.
4. The battery cover according to claim 1, characterized in that: A gap is formed between a side of the accommodating cavity close to the pole group and the pole group.
5. The battery cover according to claim 1, characterized in that: The limiting member is a colloid resistant to electrolyte and high temperature, and the limiting member is injection-molded in the accommodating cavity.
6. The battery cover according to claim 5, characterized in that: The width of the accommodating cavity is not less than 2 mm.
7. The battery cover according to claim 5, characterized in that: The opening of the accommodating cavity is arranged on a side facing the bare aluminum plate.
8. The battery cover according to any one of claims 1 to 6, characterized in that: The lower plastic plate is provided with a plurality of accommodating cavities, and the plurality of limiting members are provided in the plurality of accommodating cavities in a one-to-one correspondence.
9. The battery cover according to claim 8, characterized in that: Both ends of the electrode group are provided with electrode ears respectively, and both ends of the lower plastic plate are provided with the accommodation cavity located outside the electrode ears respectively.
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.