Upper cover assembly for single battery, single battery and battery module

Abstract

The utility model belongs to the field of batteries, and particularly relates to an upper cover assembly for a single battery, the single battery and a battery module. The problem that the battery module cannot work continuously due to thermal runaway of part of single batteries is solved. The upper cover assembly comprises an upper cover plate and a polarity terminal arranged on the upper cover plate, and the polarity terminal is insulated from the upper cover plate; the upper cover plate is an electric conductor; a conductive connecting piece is further included; the conductive connecting piece is fixed on the upper cover plate or the polarity terminal; when the temperature reaches a set threshold temperature, the conductive connecting piece deforms and is connected between the upper cover plate and the polar terminal, so that the upper cover plate and the polar terminal are electrically conducted, and the single battery becomes a resistor in a circuit of the whole battery module; and at least one part of the discharge current of the single batteries without thermal runaway in the whole battery module flows through the upper cover plate of the single batteries to continuously supply power to the load.

Description

Technical Field

[0001] This utility model belongs to the field of batteries, specifically a cover assembly for a single battery, a single battery, and a battery module. Background Technology

[0002] Currently, the market often uses multiple individual cells connected in parallel, series, or series-parallel to form battery modules (also known as battery packs).

[0003] During use, one or more individual cells in the battery module may experience thermal runaway, which may cause the entire battery module to cease operation. Summary of the Invention

[0004] The purpose of this invention is to provide a cover assembly for a single battery cell, a single battery cell, and a battery module, overcoming the problem that the battery module cannot continue to work due to thermal runaway of some single batteries cell.

[0005] The first aspect of this utility model provides a top cover assembly for a single battery, including a top cover plate and polar terminals disposed on the top cover plate, wherein the polar terminals are insulated from the top cover plate; the special feature is that the top cover plate is an electrical conductor; it also includes a conductive connector; the conductive connector is fixed on the top cover plate or the polar terminals; when the temperature reaches a set threshold temperature, the conductive connector deforms and connects between the top cover plate and the polar terminals, thereby realizing electrical conduction between the top cover plate and the polar terminals.

[0006] In the battery module, when a single cell experiences thermal runaway, the temperature of the conductive connector of that single cell rises to or exceeds a set threshold temperature, causing the conductive connector to deform due to heat and connect between the top cover and the polar terminal. This achieves an electrical connection between the top cover and the polar terminal, making the single cell a resistor in the circuit of the entire battery module. At least a portion of the discharge current of the single cells that have not experienced thermal runaway flows through the top cover of the single cell to continue supplying power to the load.

[0007] Therefore, it can be seen that even if a single cell in the battery module experiences thermal runaway, the entire battery module can still continue to operate normally and supply power to the load.

[0008] Furthermore, the conductive connector is a metal component, which is readily available and relatively inexpensive compared to other conductive materials.

[0009] Furthermore, the melting point of the metal component is less than or equal to a set threshold temperature. When the single cell experiences thermal runaway, the temperature of the metal component rises to the melting point, becomes molten, and connects between the upper cover plate and the polar terminal.

[0010] Furthermore, the metal component is an annular metal plate sleeved and fixed on the polarity terminal; a set gap exists between the annular metal plate and the upper cover plate. Compared to other structural forms, the annular metal plate is easier to fix to the polarity terminal. At the same time, when it becomes molten, as long as part of it remains in contact with any part of the sidewall of the polarity terminal and part of it is in contact with any part of the upper cover plate, an electrical connection between the polarity terminal and the upper cover plate can be achieved, resulting in high connection reliability.

[0011] Furthermore, the metal component is a metal sleeve fitted around the insulating component and fixed to the upper cover plate; a predetermined gap exists between the metal sleeve and the polarity terminal. Compared to other structural forms, when it becomes molten, as long as part of it remains in contact with any part of the sidewall of the polarity terminal and part of it is in contact with any part of the upper cover plate, an electrical connection between the polarity terminal and the upper cover plate can be achieved, resulting in high connection reliability.

[0012] Furthermore, the aforementioned single-cell battery cover assembly also includes an annular baffle sleeved around the metal part and fixed to the cover plate; the annular baffle and the polar terminal form a receiving space for the molten conductive connector. Based on the annular baffle, the molten conductive connector is confined between the polar terminal and the cover plate, ensuring a reliable electrical connection between the two.

[0013] Furthermore, the upper cover plate is provided with a first opening component. Under the action of external force or electrolyte, the first opening component forms an opening in the upper cover plate.

[0014] The second aspect of this utility model also provides a single battery, including an outer cylinder, an upper cover assembly, a lower cover assembly, and an electrode assembly; the outer cylinder, the upper cover assembly, and the lower cover assembly enclose a single battery housing, and the electrode assembly is located inside the housing; the special feature is that the upper cover assembly adopts the above-mentioned upper cover assembly for single batteries, and the polarity terminal is electrically connected to the electrode tab of the electrode assembly.

[0015] Furthermore, the lower cover assembly includes a lower cover plate and a second opening component disposed on the lower cover plate. The second opening component forms an opening in the lower cover plate under the action of external force or electrolyte; its structure may be the same as or different from the first opening component.

[0016] The third aspect of this utility model also provides a battery module, which is characterized in that it includes n individual batteries arranged in the same direction; wherein the individual batteries are the aforementioned individual batteries; and n is an integer greater than 1.

[0017] Furthermore, the aforementioned battery module also includes a housing; n individual batteries are arranged in the same direction in the inner cavity of the housing, and the housing has at least one shared chamber, the inner cavity of which is connected to the inner cavities of all individual batteries; a clearance hole is provided on the top plate of the housing corresponding to the polarity terminal of each individual battery; the polarity terminal of each individual battery extends out of the clearance hole, and the area of ​​the top plate of the housing corresponding to the clearance hole is fixedly sealed to the housing body of the individual battery.

[0018] The beneficial effects of this utility model are:

[0019] In the battery module, when a single cell experiences thermal runaway, the temperature of the conductive connector of that single cell rises to or exceeds a set threshold temperature, causing the conductive connector to deform due to heat and connect between the top cover and the polar terminal. This achieves an electrical connection between the top cover and the polar terminal, making the single cell a resistor in the circuit of the entire battery module. At least a portion of the discharge current of the single cells that have not experienced thermal runaway flows through the top cover of the single cell to continue supplying power to the load.

[0020] Therefore, it can be seen that even if a single cell in the battery module experiences thermal runaway, the entire battery module can still continue to operate normally and supply power to the load. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the top cover assembly for a single battery cell in Example 1;

[0022] Figure 2 This is an exploded view of the top cover assembly for a single battery cell in Example 1;

[0023] Figure 3 This is a cross-sectional view of the top cover assembly for a single battery cell in Example 1;

[0024] Figure 4 This is a schematic diagram of the structure of another type of top cover assembly for a single battery in Example 1;

[0025] Figure 5 This is a cross-sectional view of another type of top cover assembly for a single battery cell in Example 1;

[0026] Figure 6 This is a cross-sectional view of the top cover assembly for a single cell that experienced thermal runaway in Example 1;

[0027] Figure 7 This is a partial exploded view of another single-cell battery cover assembly in Example 1;

[0028] Figure 8 This is a cross-sectional view of the top cover assembly for a single battery cell in Example 2;

[0029] Figure 9This is a schematic diagram of the structure of a single cell in Example 3;

[0030] Figure 10 This is a cross-sectional view of a single cell in Example 3;

[0031] Figure 11 This is a schematic diagram of the battery module structure in Example 4;

[0032] Figure 12 This is a cross-sectional view of a single cell in the battery module of Example 4 that experienced thermal runaway;

[0033] Figure 13 This is a schematic diagram of the battery module structure in Example 5;

[0034] Figure 14 This is a cross-sectional view of the battery module in Example 5;

[0035] Figure 15 This is a cross-sectional view of the battery module after thermal runaway occurred in Example 5;

[0036] The reference numerals in the figure are as follows: 1. Top cover assembly; 11. Top cover plate; 12. Polar terminal; 121. First polar terminal; 122. Second polar terminal; 13. Conductive connector; 14. Insulating component; 15. Barrier ring; 16. Accommodation space; 2. Single cell; 21. Lower cover plate; 22. Second opening component; 23. Electrode assembly; 24. Electrode tab; 3. Outer shell; 31. Top plate of outer shell; 32. Clearance hole; 33. Bottom plate of outer shell; 34. Support component; 35. Electrolyte sharing chamber; 36. Gas sharing chamber. Detailed Implementation

[0037] To make the above-mentioned objectives, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this utility model.

[0038] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0039] In the description of this utility model, it should be noted that the terms "top," "bottom," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0040] A battery module consists of multiple individual cells. During use, one or more individual cells in the battery module may experience thermal runaway, which may cause the entire battery module to stop working.

[0041] In order to enable the entire battery module to continue to operate normally and supply power to the load in the event of thermal runaway of a single cell in the battery module, this utility model proposes a cover assembly for a single cell, a single cell, and a battery module.

[0042] Specifically, the single-cell battery cover assembly provided by this utility model includes a cover plate, a polar terminal disposed on the cover plate, and a conductive connector; both the polar terminal and the cover plate are electrical conductors, and the polar terminal is insulated from the cover plate; the conductive connector is fixed on the cover plate or the polar terminal; when the temperature reaches a set threshold temperature, the conductive connector deforms due to heat and connects between the cover plate and the polar terminal, thereby realizing the electrical connection between the cover plate and the polar terminal.

[0043] The single battery provided by this utility model includes an outer cylinder, an upper cover assembly, a lower cover assembly, and an electrode assembly; the outer cylinder, the upper cover assembly, and the lower cover assembly are arranged to form a single battery shell, and the electrode assembly is located inside the shell; the upper cover assembly adopts the above-mentioned upper cover assembly, and the electrode tabs of the electrode assembly are electrically connected to the polarity terminals.

[0044] The battery module provided by this utility model includes n individual batteries arranged in the same direction; the n individual batteries are electrically connected based on polarity terminals; wherein the individual batteries are the aforementioned individual batteries; and n is an integer greater than 1. The electrical connections include parallel connection, series connection, and mixed connection.

[0045] As can be seen from the above description, in this utility model, the conductive connector has the following two states:

[0046] First state: When a single cell is in normal working condition, its temperature can be assumed to be T1. The conductive connector is fixed to the top cover and is not connected to the polarity terminal; or, the conductive connector is fixed to the polarity terminal and is not connected to the top cover.

[0047] Second state: When the temperature of a single cell is T2, where T2 > T1; the temperature of the conductive connector reaches a set threshold temperature. At this temperature, the conductive connector deforms and connects between the upper cover and the polar terminal, thus realizing the electrical connection between the upper cover and the polar terminal.

[0048] T2 is close to the thermal runaway temperature of a single cell. The set threshold temperature can be adjusted according to the specific implementation situation, and a thermosensitive material adapted to the required set threshold temperature can be selected to achieve deformation at the corresponding set threshold temperature and achieve the expected effect.

[0049] In the battery module, when a single cell experiences thermal runaway, the temperature of the conductive connector of that single cell rises to or exceeds a set threshold temperature, causing the conductive connector to deform due to heat and connect between the top cover and the polar terminal. This achieves an electrical connection between the top cover and the polar terminal, making the single cell a resistor in the circuit of the entire battery module. At least a portion of the discharge current of the single cells that have not experienced thermal runaway flows through the top cover of the single cell to continue supplying power to the load.

[0050] Therefore, it can be seen that even if a single cell in the battery module experiences thermal runaway, the entire battery module can still continue to operate normally and supply power to the load.

[0051] It should be noted that:

[0052] 1. The above polarity terminal can be a single battery terminal. In order to avoid the single battery terminal height not meeting the set requirements, a terminal adapter can be connected to the single battery terminal, and the overall structure of the single battery terminal and the terminal adapter can be used as the single battery polarity terminal.

[0053] 2. Typically, for conventional square-shell batteries, the top cover plate has two polarity terminals with different polarities. In this utility model, the main example is to fix conductive connectors on both polarity terminals with different polarities.

[0054] 3. The aforementioned thermal deformation of the conductive connector can be understood as thermal expansion of the conductive connector, or as a change in state of the conductive connector after heating, such as changing from a solid state to a molten state. In this invention, materials with such properties are referred to as temperature-sensitive materials, typically temperature-sensitive metal materials, or temperature-sensitive conductive polymer materials, etc.

[0055] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0056] Example 1

[0057] This embodiment is a top cover assembly 1 for a single battery cell, the structure of which is as follows: Figure 1 , Figure 2 and Figure 3 As shown, it includes an upper cover plate 11, a polar terminal 12, and a conductive connector 13.

[0058] The upper cover plate 11 is used to enclose the lower cover assembly of the single cell battery 2 and the outer cylinder to form the outer shell of the single cell battery 2. In this embodiment, the upper cover plate 11 is a rectangular plate made of a conductive metal material, typically aluminum.

[0059] from Figure 1 and Figure 2 As can be seen from the image, the polarity terminal 12 in this embodiment is a single cell 2-terminal, which is taller than the conventional single cell 2-terminal.

[0060] In some other embodiments, when the height of the single cell 2 terminal does not meet the set requirements, a terminal adapter can be connected to the single cell 2 terminal, and the overall structure of the single cell 2 terminal and the terminal adapter can be used as the polarity terminal 12 of the single cell 2.

[0061] In addition, this embodiment includes two polarity terminals 12, both of which are fixed on the upper cover plate 11. For ease of description, in this embodiment, the two polarity terminals 12 are defined as the first polarity terminal 121 and the second polarity terminal 122, respectively, and the first polarity terminal 121 and the second polarity terminal 122 serve as the positive and negative polarity terminals 12 of the single cell 2.

[0062] Insulation between the first polarity terminal 121 and the second polarity terminal 122 and the upper cover plate 11 can be achieved by providing an insulating member 14 between them. The insulating member 14 can be a ring-shaped insulating layer formed by pouring insulating adhesive between the polarity terminal 121 and the upper cover plate 11, or an insulating sleeve disposed between the polarity terminal 121 and the upper cover plate 11, etc. The material of the insulating member 14 can be the insulating material used between the polarity terminal 12 and the upper cover plate 11 in the prior art. Furthermore, the connection method between the insulating member 14 and the polarity terminal 12 and the upper cover plate 11 can also adopt relevant existing technologies, and this embodiment does not impose specific limitations.

[0063] from Figure 1 , Figure 2 and Figure 3 As can be seen from the above, there are two conductive connectors 13 in this embodiment, both of which are annular plates. They are respectively sleeved and fixed on the first polarity terminal 121 and the second polarity terminal 122, and there is a certain gap between them and the upper cover plate 11. This gap needs to ensure that the conductive connectors 13 and the upper cover plate 11 remain insulated when the single cell 2 is in normal working condition.

[0064] In order to improve the installation stability of the conductive connector 13, the conductive connector 13 is sleeved on the polar terminal 12, so that its bottom surface is pressed against the insulating member 14. In addition, a stepped structure can be provided on the polar terminal 12, with the stepped surface flush with the upper end surface of the insulating member 14, and the bottom surface of the conductive connector 13 is pressed against both the upper end surface of the insulating member 14 and the stepped surface.

[0065] In some other embodiments, other shapes may be used, such as a semi-circular metal plate, which is fixed on the polar terminal 12, but its stability is weaker than that of this embodiment.

[0066] In addition, this embodiment uses an annular plate, which is easier to fix to the polarity terminal compared to other structural forms. At the same time, when it becomes molten, as long as part of it keeps in contact with any part of the side wall of the polarity terminal and part of it keeps in contact with any part of the upper cover plate, the electrical connection between the polarity terminal and the upper cover plate can be achieved, which has high connection reliability.

[0067] In this embodiment, the conductive connector 13 is made of metal with a melting point less than or equal to a set threshold temperature. At the set temperature threshold, the metal becomes molten, with part of the structure still in contact with the polar terminal 12 and part flowing to the upper cover plate 11 under the action of gravity, thereby realizing the electrical connection between the polar terminal 12 and the upper cover plate 11.

[0068] like Figure 4 and Figure 5 As shown, to prevent the conductive connector 13 from detaching from the polarity terminal 12 when it becomes molten, this embodiment can also provide a blocking ring 15 around the conductive connector 13, and the lower end of the blocking ring 15 is fixed to the area of ​​the upper cover plate 11 around the insulating member 14, forming a receiving space 16 for the molten conductive connector 13 between the blocking ring 15 and the insulating member 14 or the polarity terminal 12. Figure 6 As shown, at a set temperature threshold, the molten conductive connector 13 is confined within the receiving space 16, partially contacting the polar terminal 12 and partially contacting the upper cover plate 11, which ensures a reliable electrical connection between the two.

[0069] In addition, such as Figure 7 As shown, a chamfer can also be provided at the connection between the upper end face and the outer peripheral face of the insulating member 14, so that the molten conductive connector 13 can flow more easily to the upper cover plate 11 under the action of gravity.

[0070] It should be noted that:

[0071] 1. The blocking ring 15 can be an electrical conductor or an electrical insulator. When it is an electrical conductor, the molten conductive connector 13 partially contacts the polar terminal 12, and partially only needs to contact the blocking ring 15 to ensure the electrical connection between the polar terminal 12 and the upper cover plate 11.

[0072] 2. The size of the accommodating space 16 of the conductive connector 13 can be determined based on the volume of the conductive connector 13 or the volume of the molten conductive connector 13.

[0073] When the accommodating space of the conductive connector 13 is too large, that is, much larger than the volume of the conductive connector 13 or the volume of the molten conductive connector 13, the conductive connector 13 becomes molten under the set temperature threshold. Under the action of gravity, it flows into the accommodating space of the conductive connector 13, which may cause the molten conductive connector 13 to detach from the polar terminal 12, making it impossible to achieve the electrical connection between the polar terminal 12 and the upper cover plate 11.

[0074] When the blocking ring 15 with an electrical insulator is used, and the accommodating space of the conductive connector 13 is too small, that is, much smaller than the volume of the conductive connector 13 or the volume of the molten conductive connector 13, the gap between the blocking ring 15 and the polar terminal 12 is small, that is, the area of ​​the upper cover plate 11 between the polar terminal 12 or the insulating member 14 and the blocking ring 15 is small, which may result in a small contact area between the molten conductive connector 13 and the upper cover plate 11, reducing the reliability of the electrical connection between the polar terminal 12 and the upper cover plate 11.

[0075] When the blocking ring 15 with an electrical conductor is used, and the accommodating space of the conductive connector 13 is too small, that is, the gap between the blocking ring 15 and the polar terminal 12 is small, it is necessary to consider the insulation between the blocking ring 15 and the polar terminal 12 under normal working conditions.

[0076] In this embodiment, the temperature threshold corresponds to the temperature that the polar terminal 12 will reach when the single cell 2 experiences thermal runaway. The corresponding conductive connector 13 can be made of a metal or alloy with a melting point between 200 and 300 degrees Celsius. For example, metals such as tin and bismuth can be selected.

[0077] In some other embodiments, the temperature threshold is not limited to a specific temperature value, but can be a temperature value that is adjusted according to the specific operating conditions of the individual battery cell 2 (e.g., battery voltage, load size, resistance of components in the circuit), ambient environmental parameters (e.g., ambient temperature, humidity), etc. The threshold temperature can be adjusted according to the specific implementation, and a temperature-sensitive material adapted to the required threshold temperature can be selected to achieve the expected thermal runaway response measures.

[0078] In some other embodiments, other temperature-sensitive conductors may be selected. These conductors expand when heated at a set threshold temperature and come into contact with the upper cover plate 11 or the blocking ring 15 of the conductor to achieve electrical connection between the polarity terminal 12 and the upper cover plate 11.

[0079] In this embodiment, a first opening component can also be provided on the upper cover plate 11, which is located between the two polarity terminals 12. Under the action of external force or electrolyte, the first opening component can detach from the upper cover plate 11 of the single cell 2 and form a through hole in the upper cover plate 11 that penetrates the inner cavity of the outer casing. The first opening component adopts an existing structure, such as the first opening component disclosed in Chinese Patent CN221327991U, the sealing device disclosed in Chinese Patent CN117476997A, and the opening device disclosed in CN117477117A.

[0080] Example 2

[0081] This embodiment also describes a top cover assembly 1 for a single battery cell, including a top cover plate 11, polarity terminals 12, and conductive connectors 13, the structure of which is as follows: Figure 8 As shown, the upper cover plate 11, the polarity terminal 12, and the fixing method of the polarity terminal 12 to the upper cover plate 11 are all the same as in Embodiment 1, and will not be described again here. Unlike Embodiment 1, in this embodiment, the conductive connector 13 is fixed on the upper cover plate. Similar to Embodiment 1, the electrical connection between the polarity terminal 12 and the upper cover plate 11 can also be achieved at a set threshold temperature.

[0082] Specifically, such as Figure 8 As shown, in this embodiment, there are two conductive connectors 13, both of which are sleeve structures. They are respectively sleeved around the insulating members 14 corresponding to the two polarity terminals 12, with a certain gap between them and the polarity terminals 12. The bottom end is fixed to the area of ​​the upper cover plate 11 around the insulating member 14. The gap between the conductive connector 13 and the polarity terminal 12 needs to ensure that the conductive connector 13 and the polarity terminal 12 remain insulated under the normal working state of the single cell 2.

[0083] In this embodiment, the conductive connector 13 is also made of a metal with a melting point lower than the set temperature threshold. At the set temperature threshold, it becomes molten. Part of the structure is still in contact with the upper cover plate 11, and part is in contact with the polar terminal 12, thus realizing the electrical connection between the upper cover plate 11 and the polar terminal 12.

[0084] To prevent the conductive connector 13 from flowing onto the upper cover plate 11 due to gravity when it becomes molten, thus hindering contact with the polarity terminal 12, this embodiment fixes a blocking ring 15 around the upper cover plate 11 area surrounding the conductive connector 13. A receiving space 16 for the molten conductive connector 13 is formed between the blocking ring 15 and the insulating member 14 or the polarity terminal 12. At a set temperature threshold, the molten conductive connector 13 is confined within this space, partially contacting the polarity terminal 12 and partially contacting the upper cover plate 11, ensuring a reliable electrical connection between them. For details, please refer to [reference needed]. Figure 6 The structure shown.

[0085] It should be noted that:

[0086] 1. The blocking ring 15 can be an electrical conductor or an electrical insulator. When it is an electrical conductor, the molten conductive connector 13 partially contacts the polar terminal 12, and partially only needs to contact the blocking ring 15 to ensure the electrical connection between the polar terminal 12 and the upper cover plate 11.

[0087] 2. The accommodating space of the conductive connector 13 can be determined according to the volume of the conductive connector 13 or the volume of the molten conductive connector 13;

[0088] When the accommodating space of the conductive connector 13 is too large, that is, much larger than the volume of the conductive connector 13 or the volume of the molten conductive connector 13, the conductive connector 13 becomes molten under the set temperature threshold. Under the action of gravity, it flows into the accommodating space of the conductive connector 13, which may make it difficult for the molten conductive connector 13 to contact the polar terminal 12, and thus fail to achieve the electrical connection between the polar terminal 12 and the upper cover plate 11.

[0089] When the blocking ring 15 with an electrical insulator is used, and the accommodating space of the conductive connector 13 is too small, that is, much smaller than the volume of the conductive connector 13 or the volume of the molten conductive connector 13, the gap between the blocking ring 15 and the polar terminal 12 is small, that is, the area of ​​the upper cover plate 11 between the polar terminal 12 and the blocking ring 15 is small. This may result in a small contact area between the molten conductive connector 13 and the upper cover plate 11, reducing the reliability of the electrical connection between the polar terminal 12 and the upper cover plate 11.

[0090] When the blocking ring 15 with an electrical conductor is used, and the accommodating space of the conductive connector 13 is too small, that is, the gap between the blocking ring 15 and the polar terminal 12 is small, it is necessary to consider the insulation between the blocking ring 15 and the polar terminal 12 under normal working conditions.

[0091] In this embodiment, the temperature threshold corresponds to the temperature that the polar terminal 12 will reach when the single cell 2 experiences thermal runaway. The corresponding conductive connector 13 can be made of a metal or alloy with a melting point between 200 and 300 degrees Celsius. For example, metals such as tin and bismuth can be selected.

[0092] In some other embodiments, the temperature threshold is not limited to a specific temperature value, but can be a temperature value that is adjusted according to the specific operating conditions of the individual battery cell 2 (e.g., battery voltage, load size, resistance of components in the circuit), ambient environmental parameters (e.g., ambient temperature, humidity), etc. The threshold temperature can be adjusted according to the specific implementation, and a temperature-sensitive material adapted to the required threshold temperature can be selected to achieve the expected thermal runaway response measures.

[0093] In order to improve the installation stability of the conductive connector 13, the conductive connector 13 is clamped between the insulating member 14 and the blocking ring 15 in this embodiment.

[0094] In some other embodiments, other shapes may be used, such as a rectangular metal plate, which is fixed to the upper cover plate 11 and clamped between the insulating member 14 and the blocking ring 15. However, its stability is weaker than that of this embodiment.

[0095] In addition, this embodiment uses a sleeve structure. Compared with other structural forms, when it becomes molten, as long as part of it keeps in contact with any part of the side wall of the polar terminal and part of it keeps in contact with any part of the upper cover plate, the electrical connection between the polar terminal and the upper cover plate can be achieved, which has high connection reliability.

[0096] Example 3

[0097] This embodiment is a single-cell battery, the structure of which is as follows: Figure 9 and Figure 10 As shown, it includes an outer shell and an electrode assembly 23 and an electrolyte located within the outer shell; wherein the outer shell is formed by an outer cylinder, a lower cover assembly, and an upper cover assembly 1 as described in the above embodiments. Figure 9 and Figure 10 Taking the upper cover assembly 1 in Embodiment 1 as an example, the first polarity terminal 121 and the second polarity terminal 122 on the upper cover assembly 1 are electrically connected to the positive and negative electrodes 24 of the electrode assembly 23, respectively. Figure 10 (Connection structure not shown).

[0098] In this embodiment, the lower cover assembly includes a lower cover plate 21, and a second opening member 22 may be provided on the lower cover plate 21. This second opening member 22 can detach from the lower cover plate 21 of the individual battery 2 under external force or electrolyte action, and forms a through hole in the lower cover plate 21 that penetrates the inner cavity of the outer casing. The second opening member 22 can also be a conventional structure, such as the opening member disclosed in Chinese Patent CN221327991U, the sealing device disclosed in Chinese Patent CN117476997A, and the opening device disclosed in CN117477117A. The structure of the second opening member 22 can be the same as or different from the first opening member.

[0099] Example 4

[0100] like Figure 11 As shown, this embodiment is a battery module, including 12 individual battery cells 2 arranged in the same direction as in embodiment 3. In some other embodiments, the number of individual battery cells 2 can be adjusted according to actual needs. The 12 individual battery cells 2 are electrically connected based on polarity terminals 12, and this electrical connection can be parallel, series, or a combination of both.

[0101] When each individual battery cell 2 has a second opening part 22 on its lower cover plate 21, the second opening part 22 of each individual battery cell 2 can be opened, and a hollow component can be used to connect the inner cavities of all individual batteries 2 to achieve electrolyte sharing, reduce the differences between individual batteries 2, and optimize the cycle performance of the battery module. It should be noted that when each individual battery cell 2 achieves electrolyte sharing, the individual batteries 2 are preferably connected in parallel.

[0102] When each individual battery cell 2 has a first opening component on its upper cover plate 11, the first opening component of each individual battery cell 2 can be opened, and another hollow component can be used to connect the inner cavities of all individual battery cells 2 to achieve gas sharing, gas balance, and further optimize the cycle performance of the battery module.

[0103] like Figure 12 As shown, in the battery module, if any single cell 2 experiences thermal runaway, the temperature of the conductive connector 13 of the single cell 2 rises to or exceeds a set threshold temperature, causing the conductive connector 13 to be heated and become molten. The molten material flows to the receiving space 16 of the conductive connector 13 and connects between the upper cover plate 11 and the polar terminal 12, thereby realizing the electrical connection between the upper cover plate 11 and the polar terminal 12. This makes the single cell 2 a resistor in the circuit of the entire battery module. At least a portion of the discharge current of the single cell 2 that has not experienced thermal runaway flows through the upper cover plate 11 of the single cell 2 to continue to supply power to the load.

[0104] Example 5

[0105] This embodiment presents another type of battery module, differing from embodiment 4 in that it also includes a housing 3, the specific structure of which is as follows: Figure 13 and Figure 14 As shown.

[0106] Figure 13 and Figure 14 In Figure 11 Taking the battery module shown as an example, an outer casing 3 is added.

[0107] from Figures 13 to 14 As can be seen from this, this embodiment is in Figure 11 A housing 3 is added to the battery module shown, and the individual battery cells 2 are arranged inside the housing 3. A clearance hole 32 is provided on the top plate 31 of the housing to allow the polarity terminals 12 of each individual battery cell 2 to extend. Each individual battery cell 2's polarity terminal 12 extends out of the corresponding clearance hole 32, and the area of ​​the top plate 31 corresponding to the clearance hole 32 is fixedly sealed to the housing of the individual battery cell 2. In this embodiment, a blocking ring 15 is used to achieve the fixed seal between the area of ​​the top plate 31 corresponding to the clearance hole 32 and the housing of the individual battery cell 2; specifically as follows... Figure 14 As shown, in this embodiment, the blocking ring 15 has an L-shaped cross section. The transverse ring plate and the area of ​​the cover plate 11 of the single cell 2 around the insulating member 14 are fixed. The longitudinal ring plate extends into the clearance hole 32 and is sealed to the wall of the clearance hole 32.

[0108] In this embodiment, the blocking ring 15 can both form a space 16 for receiving the conductive connector 13 between itself and the polar terminal 12, and also achieve a fixed seal between the area of ​​the outer shell top plate 31 corresponding to the clearance hole 32 and the shell of the single battery 2.

[0109] A support member 34 extending in the x-direction is provided between the bottom plate 33 of the outer casing and each individual battery cell 2 to form a liquid channel, serving as an electrolyte sharing chamber 35. When the lower cover plate 21 of each individual battery cell 2 has a second opening part 22, the second opening part 22 of the lower cover plate 21 of each individual battery cell 2 can be opened, and the inner cavities of all individual battery cells 2 can be connected based on the electrolyte sharing chamber 35 to realize electrolyte sharing, reduce the differences between individual battery cells 2, and optimize the cycle performance of the battery module. It should be noted that when the individual battery cells 2 realize electrolyte sharing, the individual battery cells 2 are preferably connected in parallel.

[0110] Figure 13 and Figure 14 In the case, a boss extending in the x-direction is provided on the top plate 31 of the outer casing. A gas channel is opened on the boss. The gas channel is connected to the inner cavity of the outer casing 3 and serves as a gas sharing chamber 36, which is connected to the gas area of ​​the inner cavity of each individual battery cell 2. When gas is generated in the inner cavity of the individual battery cell 2, the inner cavity of the gas channel can also serve as a gas containing cavity to alleviate the problem of the outer casing 3 bulging caused by gas generation.

[0111] In some other embodiments, only an electrolyte shared chamber 35 or a gas shared chamber 36 may be provided.

[0112] like Figure 15 As shown, in the battery module, if any single cell 2 experiences thermal runaway, the temperature of the conductive connector 13 of the single cell 2 rises to or exceeds a set threshold temperature, causing the conductive connector 13 to be heated and become molten. The molten material flows to the receiving space 16 of the conductive connector 13 and connects between the upper cover plate 11 and the polar terminal 12, thereby realizing the electrical connection between the upper cover plate 11 and the polar terminal 12. This makes the single cell 2 a resistor in the circuit of the entire battery module. At least a portion of the discharge current of the single cell 2 that has not experienced thermal runaway flows through the upper cover plate 11 of the single cell 2 to continue to supply power to the load.

Claims

1. A cover assembly for a single-cell battery, comprising a cover plate and polar terminals disposed on the cover plate, wherein the polar terminals are insulated from the cover plate; characterized in that: The top cover is an electrical conductor; it also includes a conductive connector; the conductive connector is fixed on the top cover or polar terminal; when the temperature reaches a set threshold temperature, the conductive connector deforms to achieve electrical conduction between the top cover and the polar terminal.

2. The top cover assembly for a single battery cell according to claim 1, characterized in that: The conductive connector is a metal component.

3. The top cover assembly for a single battery cell according to claim 2, characterized in that: The melting point of the metal component is less than or equal to a set threshold temperature.

4. The top cover assembly for a single battery cell according to claim 3, characterized in that: The metal component is an annular metal plate sleeved and fixed on the polarity terminal; there is a set gap between the annular metal plate and the upper cover plate.

5. The top cover assembly for a single battery cell according to claim 3, characterized in that: The metal component is a metal sleeve that is sleeved around the insulating component and fixed to the upper cover plate; there is a set gap between the metal sleeve and the polarity terminal.

6. The cover assembly for a single battery cell according to any one of claims 3-5, characterized in that: It also includes an annular baffle that is sleeved around the metal part and fixed to the upper cover plate; the annular baffle and the polar terminal form a space for receiving the molten conductive connector.

7. The top cover assembly for a single battery cell according to claim 1, characterized in that: The top cover has a first opening component.

8. A single-cell battery, comprising an outer cylinder, an upper cover assembly, a lower cover assembly, and an electrode assembly; the outer cylinder, the upper cover assembly, and the lower cover assembly enclose a single-cell battery casing, and the electrode assembly is located within the casing; characterized in that: The top cover assembly adopts the top cover assembly for a single cell as described in any one of claims 1-7, wherein the polarity terminal is electrically connected to the tab of the electrode assembly.

9. The single-cell battery according to claim 8, characterized in that: The lower cover assembly includes a lower cover plate and a second opening component disposed on the lower cover plate.

10. A battery module, characterized in that: It includes n individual cells arranged in the same direction; wherein the individual cells are the individual cells as described in claim 8 or 9; and n is an integer greater than 1.

11. The battery module according to claim 10, characterized in that: It also includes a housing; n individual cells are arranged in the same direction in the inner cavity of the housing, the housing has at least one shared chamber, the inner cavity of the shared chamber is in communication with the inner cavities of all individual cells; the top plate of the housing has clearance holes corresponding to the polarity terminals of each individual cell; the polarity terminals of each individual cell extend out of the clearance holes, and the area of ​​the top plate of the housing corresponding to the clearance holes is fixedly sealed to the housing body of the individual cells.

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