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

Abstract

The present invention belongs to the field of batteries, and particularly relates to an upper cover assembly for a battery cell, a battery cell, and a battery module, which solve the problem whereby a battery module cannot continue to operate due to the thermal runaway of a battery cell. The upper cover assembly comprises a conductive connector, an upper cover plate of an electrical conductor, and a polarity terminal arranged on the upper cover plate and insulated therefrom. When the temperature of the conductive connector reaches a set threshold temperature, the conductive connector deforms to realize electrical conduction between the upper cover plate and the polarity terminal. The battery cell comprises the upper cover assembly, and the battery module is composed of a plurality of battery cells. In the battery module, when a battery cell undergoes thermal runaway, the conductive connector of said battery cell deforms and is connected between the upper cover plate and the polarity terminal, such that said battery cell becomes a resistor in a circuit of the entire battery module, and at least some of the discharge current of the battery cells that have not experienced thermal runaway in the entire battery module flows through the upper cover plate of said battery cell so as to continue supplying power to a load.

Description

Top cover assembly for single battery cell, single battery cell and battery module Technical Field

[0001] This invention 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 the present invention provides a top cover assembly for a single battery, including a top cover plate with an electrical conductor and polar terminals disposed on the top cover plate, wherein the polar terminals are insulated from the top cover plate; characterized in that: it further includes a conductive connector, which deforms when the temperature reaches a set threshold temperature to achieve 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 aforementioned conductive connector is fixed to the upper cover plate or polarized terminal.

[0009] Furthermore, the aforementioned conductive connector is made of metal, which is readily available and relatively inexpensive compared to other conductive materials.

[0010] Furthermore, the melting point of the aforementioned metal component is less than or equal to a set threshold temperature. When a single cell experiences thermal runaway, the temperature of the metal component rises to its melting point, becoming molten and connecting between the upper cover plate and the polar terminal.

[0011] Furthermore, the aforementioned metal component is an annular metal plate sleeved and fixed on the polarity terminal; a predetermined 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. Furthermore, 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 remains 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 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.

[0013] Furthermore, the aforementioned single-cell battery cover assembly also includes an annular baffle that is 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.

[0014] 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.

[0015] Furthermore, the cover assembly for a single cell also includes an annular insulating member;

[0016] Mounting holes are provided on the top cover; polarity terminals pass through the mounting holes;

[0017] An annular insulating member is sealed and fixed between the polarity terminal and the upper cover plate; a channel is opened on the annular insulating member along its thickness direction;

[0018] The conductive connector is fixed on the polar terminal and located above the annular insulating member. When the temperature reaches the set threshold temperature, the conductive connector deforms and partially fills the channel of the annular insulating member, thereby achieving electrical conductivity between the upper cover plate and the polar terminal.

[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. Part of it fills the channel of the annular insulating member and connects between the top cover and the polar terminal, thereby achieving an electrical connection between the top cover and the polar terminal. This makes 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 in the entire battery module 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.

[0021] Furthermore, the aforementioned channel is at least one through hole formed on the annular insulating member.

[0022] Furthermore, the aforementioned conductive connector is made of metal, which is readily available and relatively inexpensive compared to other conductive materials.

[0023] Furthermore, the melting point of the aforementioned metal component is less than or equal to a set threshold temperature. When a single cell experiences thermal runaway, the temperature of the metal component rises to its melting point, becomes molten, flows into the through hole or notch, and connects between the upper cover plate and the polar terminal.

[0024] Furthermore, the aforementioned metal component is an annular metal plate sleeved and fixed on the polarity terminal. 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 side wall of the polarity terminal and part of it fills the channel and contacts 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.

[0025] 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.

[0026] Furthermore, the top cover assembly for a single battery cell also includes an insulating plate; the aforementioned conductive connector is a connecting plate, and the top cover plate, connecting plate, and insulating plate are stacked in sequence, with through mounting holes formed on the top cover plate and the insulating plate in the stacking direction;

[0027] The polarity terminal passes through the mounting hole and is fixedly sealed between the upper cover plate;

[0028] The insulating board is an electrical insulator;

[0029] A channel is provided between the connecting plate and the polarity terminal;

[0030] When the temperature reaches the set threshold temperature, the connecting plate deforms due to heat, and part of the structure fills the channel, realizing electrical conduction between the top cover and the polarity terminal.

[0031] In a battery module, when a single cell experiences thermal runaway, the temperature of the connecting plate of that single cell rises to or exceeds a set threshold temperature, causing the connecting plate to deform due to heat. Part of the structure fills the channel and connects the upper cover plate and the polar terminal through the channel, thereby achieving electrical conduction between the upper cover plate and the polar terminal. This makes 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 in the entire battery module that have not experienced thermal runaway flows through the upper cover assembly of the single cell to continue supplying power to the load.

[0032] 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.

[0033] Furthermore, the polarity terminal includes a limiting part and an electrical connection part; the electrical connection part of the polarity terminal passes through the mounting hole and is fixedly sealed between the terminal and the upper cover plate, and the electrical connection part is located on the side of the upper cover plate, while the limiting part is limited on the side of the insulating plate.

[0034] Furthermore, the aforementioned channel can be at least one through hole formed on the insulating plate, the through hole penetrating the insulating plate along the thickness direction of the insulating plate; and the through hole is located directly above the polarity terminal limiting portion;

[0035] When the temperature reaches the set threshold temperature, the connecting plate deforms due to heat, and part of the structure fills the through hole. It is connected between the polarity terminal limiting part and the upper cover plate through the through hole to realize the electrical connection between the upper cover plate and the polarity terminal.

[0036] Furthermore, the aforementioned channel can also be a second annular gap between the polar terminal and the insulating plate; specifically, when the diameter of the mounting hole on the insulating plate is larger than the diameter of the mounting hole on the upper cover plate; after the polar terminal passes through the mounting hole, the aforementioned second annular gap exists between it and the insulating plate.

[0037] When the temperature reaches the set threshold temperature, the aforementioned connecting plate deforms due to heat, and part of the structure fills the second annular gap. It is connected between the polar terminal and the upper cover plate through the second annular gap, thereby realizing the electrical connection between the upper cover plate and the polar terminal.

[0038] Furthermore, the aforementioned connecting plate is a metal plate, which is readily available and relatively inexpensive compared to other conductive materials. The melting point of the aforementioned metal plate is less than or equal to a set threshold temperature. When a single cell experiences thermal runaway, the temperature of the metal plate rises to its melting point, becoming molten, and is connected between the upper cover plate and the polar terminal through the aforementioned channel.

[0039] Furthermore, the aforementioned metal plate is an annular metal plate; the polar terminal penetrates the inner hole of the annular metal plate and has a gap between it and the inner hole to ensure electrical insulation between the polar terminal and the annular metal plate under normal operating conditions.

[0040] Furthermore, the aforementioned top cover assembly for a single battery also includes an insulating sealing ring; the insulating sealing ring is sleeved on the polar terminal and clamped between the top cover plate and the polar terminal limiting part, thereby improving the sealing performance between the polar terminal and the top cover plate.

[0041] Furthermore, the upper cover assembly may also be provided with a first opening component. The first opening component forms an opening in the upper cover assembly under the action of external force or electrolyte.

[0042] A second aspect of the present invention also provides a single battery cell, 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 are arranged to form a single battery cell 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 a single battery cell, and the polarity terminal is electrically connected to the tab of the electrode assembly.

[0043] 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.

[0044] A third aspect of the present invention also provides a battery module, characterized in that it includes n individual battery cells arranged in the same direction; wherein the individual battery cells are the aforementioned individual battery cells; and n is an integer greater than 1.

[0045] 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.

[0046] The beneficial effects of this invention are:

[0047] 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.

[0048] 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

[0049] Figure 1 is a schematic diagram of the structure of the top cover assembly for a single battery in Example 1;

[0050] Figure 2 is an exploded view of the top cover assembly for a single battery in Example 1;

[0051] Figure 3 is a cross-sectional view of the top cover assembly for a single battery cell in Example 1;

[0052] Figure 4 is a structural schematic diagram of another type of top cover assembly for a single cell in Example 1;

[0053] Figure 5 is a cross-sectional view of another single-cell battery cover assembly in Embodiment 1;

[0054] Figure 6 is a cross-sectional view of the top cover assembly for a single cell that experienced thermal runaway in Example 1;

[0055] Figure 7 is a partial explosion diagram of another single-cell battery cover assembly in Example 1;

[0056] Figure 8 is a cross-sectional view of the top cover assembly for a single battery cell in Example 2;

[0057] Figure 9 is a schematic diagram of the structure of a single cell in Example 3;

[0058] Figure 10 is a cross-sectional view of a single cell in Example 3;

[0059] Figure 11 is a schematic diagram of the battery module in Example 4;

[0060] Figure 12 is a cross-sectional view of a single cell in the battery module of Example 4 that experienced thermal runaway;

[0061] Figure 13 is a schematic diagram of the battery module in Example 5;

[0062] Figure 14 is a cross-sectional view of the battery module in Example 5;

[0063] Figure 15 is a cross-sectional view of the battery module after thermal runaway occurred in Example 5;

[0064] Figure 16 is a schematic diagram of the structure of the top cover assembly for a single battery in Example 6;

[0065] Figure 17 is an exploded view of the top cover assembly for a single battery in Example 6;

[0066] Figure 18 is a cross-sectional view of the top cover assembly for a single battery cell in Embodiment 6;

[0067] Figure 19 is a structural schematic diagram of another type of top cover assembly for a single cell in Example 6;

[0068] Figure 20 is a cross-sectional view of the top cover assembly for a single cell that experienced thermal runaway in Example 6;

[0069] Figure 21 is a schematic diagram of the structure of a single cell in Example 7;

[0070] Figure 22 is a cross-sectional view of a single cell in Example 7;

[0071] Figure 23 is a schematic diagram of the battery module in Example 8;

[0072] Figure 24 is a schematic diagram of the battery module in Example 9;

[0073] Figure 25 is a cross-sectional view of the battery module in Example 9;

[0074] Figure 26 is a partial cross-sectional view of the battery module in Example 9;

[0075] Figure 27 is a cross-sectional view of the battery module after thermal runaway occurred in Example 9;

[0076] Figure 28 is a structural schematic diagram of the top cover assembly for a single battery in Example 10;

[0077] Figure 29 is a cross-sectional view of the top cover assembly for a single battery cell in Example 10;

[0078] Figure 30 is an exploded view of the top cover assembly for a single battery in Example 10;

[0079] Figure 31 is a cross-sectional view of the top cover assembly for a single cell that experienced thermal runaway in Example 10;

[0080] Figure 32 is a cross-sectional view of another single-cell battery cover assembly in another embodiment;

[0081] Figure 33 is an exploded view of another single-cell battery cover assembly in another embodiment;

[0082] Figure 34 is a cross-sectional view of the top cover assembly for a single battery cell in Example 11;

[0083] Figure 35 is a cross-sectional view of the top cover assembly for a single cell that experienced thermal runaway in Example 11;

[0084] Figure 36 is a cross-sectional view of a top cover assembly for a single battery cell in Embodiment 12;

[0085] Figure 37 is a cross-sectional view of another single-cell battery cover assembly in Embodiment 12;

[0086] Figure 38 is a schematic diagram of the structure of a single cell in Example 13;

[0087] Figure 39 is a schematic diagram of the battery module in Example 14;

[0088] Figure 40 is a schematic diagram of the battery module in Example 15;

[0089] Figure 41 is a cross-sectional view of the battery module in Example 15;

[0090] Figure 42 is an enlarged view of the region shown in Figure 41a;

[0091] Figure 43 is a partial cross-sectional view of the battery module after thermal runaway occurred in Example 15.

[0092] 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. Receiving 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; 21. Top cover plate; 22. Polar terminal; 221. Limiting part; 222. Electrical connection part; 23. Conductive connector; 24. Annular insulating member; 241. Notch; 25. Through hole; 26. Bottom cover plate; 261. Second opening part; 27. Single cell; 28. Outer casing; 281. Top plate of outer casing; 282. Bottom plate of outer casing; 29. ​​Electrolyte sharing chamber; 210. Gas sharing chamber; 211. Sealing connector; 212. Clearance hole; 213. Support member; 311. Top cover assembly; 3111. Top cover plate; 3112. Connecting plate; 3113. Insulating plate; 312. Polar terminal; 3121. First polar terminal; 3122. Second polar terminal; 3123. Limiting part; 3124. Electrical connection part; 3125. Base; 3126. Column; 313. First mounting hole; 314. Second mounting hole; 315. Insulating component; 316. Through hole; 317. Second annular gap; 318. Insulating sealing ring; 319. First annular gap; 32. Single cell; 321. Lower cover plate; 322. Second opening piece; 33. Outer shell; 331. Top plate of outer shell; 332. Clearance hole; 333. Bottom plate of outer shell; 334. Support member; 335. Electrolyte sharing chamber; 336. Gas sharing chamber; 337. Sealing connection member. Detailed Implementation

[0093] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0094] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0095] In the description of this invention, it should be noted that the terms "top," "bottom," etc., indicating orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the invention 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 the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0096] 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.

[0097] In order to ensure that the entire battery module can continue to operate normally and supply power to the load in the event of thermal runaway of a single cell in the battery module, Examples 1 to 5 propose a cover assembly for a single cell, a single cell, and a battery module.

[0098] Specifically, the top cover assembly for a single battery provided in Examples 1 to 5 includes a top cover plate, a polar terminal disposed on the top cover plate, and a conductive connector; both the polar terminal and the top cover plate are electrical conductors, and the polar terminal is insulated from the top cover plate; the conductive connector is fixed on the top 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 top cover plate and the polar terminal, thereby realizing the electrical connection between the top cover plate and the polar terminal.

[0099] The single-cell battery provided in Examples 1 to 5 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 enclose to form a single-cell battery housing, and the electrode assembly is located inside the housing; the upper cover assembly adopts the above-described upper cover assembly, and the electrode tabs of the electrode assembly are electrically connected to the polarity terminals.

[0100] The battery modules provided in Examples 1 to 5 include n individual battery cells arranged in the same direction; the n individual battery cells are electrically connected based on polarity terminals; wherein the individual battery cells are the aforementioned individual battery cells; and n is an integer greater than 1. The electrical connections include parallel connection, series connection, and mixed connection.

[0101] As can be seen from the above description, in Examples 1 to 5, the conductive connector has the following two states:

[0102] 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.

[0103] 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.

[0104] 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.

[0105] 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.

[0106] 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.

[0107] It should be noted that:

[0108] 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.

[0109] 2. Typically, for conventional square-shell batteries, the top cover plate is provided with two polarity terminals of different polarities. In Examples 1 to 5, the main example is that conductive connectors are fixed on both polarity terminals of different polarities.

[0110] 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 Examples 1 to 5, materials with this property are referred to as temperature-sensitive materials. Temperature-sensitive metal materials or temperature-sensitive conductive polymer materials can be selected.

[0111] The following describes Embodiments 1 to 5 in further detail with reference to the accompanying drawings and specific embodiments.

[0112] Example 1

[0113] This embodiment is a top cover assembly 1 for a single battery cell, the structure of which is shown in Figures 1, 2 and 3, including a top cover plate 11, polar terminals 12 and conductive connectors 13.

[0114] 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.

[0115] As can be seen from Figures 1 and 2, the polarity terminal 12 in this embodiment is a single cell 2-terminal, which is taller than the conventional single cell 2-terminal.

[0116] 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.

[0117] 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.

[0118] 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 prior art, and this embodiment does not impose specific limitations.

[0119] As can be seen from Figures 1, 2 and 3, 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.

[0120] 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.

[0121] 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.

[0122] 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.

[0123] 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.

[0124] As shown in Figures 4 and 5, to prevent the conductive connector 13 from detaching from the polarity terminal 12 when it becomes molten, this embodiment can also provide a retaining ring 15 around the conductive connector 13. The lower end of the retaining 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 retaining ring 15 and the insulating member 14 or the polarity terminal 12. As shown in Figure 6, at a set temperature threshold, the molten conductive connector 13 is confined within the receiving space 16, partially contacting the polarity terminal 12 and partially contacting the upper cover plate 11, ensuring a reliable electrical connection between the two.

[0125] In addition, as shown in Figure 7, a chamfer can 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.

[0126] It should be noted that:

[0127] 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.

[0128] 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.

[0129] 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.

[0130] 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.

[0131] 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.

[0132] 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.

[0133] 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.

[0134] 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.

[0135] 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.

[0136] Example 2

[0137] This embodiment is also a top cover assembly 1 for a single battery cell, including a top cover plate 11, polar terminals 12, and conductive connectors 13, the structure of which is shown in Figure 8. The top cover plate 11, polar terminals 12, and the fixing method of polar terminals 12 to the top cover plate 11 are the same as in Embodiment 1, and will not be described again here. Unlike Embodiment 1, in this embodiment, the conductive connectors 13 are fixed to the top cover plate. Similar to Embodiment 1, electrical connection between the polar terminals 12 and the top cover plate 11 can also be achieved at a set threshold temperature.

[0138] Specifically, as shown in Figure 8, 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.

[0139] 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.

[0140] 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 region 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. See Figure 6 for a specific example of this structure.

[0141] It should be noted that:

[0142] 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.

[0143] 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;

[0144] 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.

[0145] 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.

[0146] 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.

[0147] 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.

[0148] 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.

[0149] 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.

[0150] 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.

[0151] 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.

[0152] Example 3

[0153] This embodiment is a single-cell battery, the structure of which is shown in Figures 9 and 10. It includes an outer casing and an electrode assembly 23 and an electrolyte located inside the outer casing. The outer casing is formed by an outer cylinder, a lower cover assembly, and an upper cover assembly 1 as described in the above embodiment. Figures 9 and 10 use 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 (the connection structure is not shown in Figure 10).

[0154] 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 CN221327991 U, 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.

[0155] Example 4

[0156] As shown in Figure 11, this embodiment is a battery module, including 12 individual battery cells 2 from Embodiment 3 arranged in the same direction. 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.

[0157] 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.

[0158] 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.

[0159] As shown in Figure 12, 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.

[0160] Example 5

[0161] This embodiment is another type of battery module. Its structure differs from that of embodiment 4. The battery module in this embodiment also has a housing 3, and the specific structure is shown in Figures 13 and 14.

[0162] Figures 13 and 14 illustrate an example of adding a housing 3 to the battery module shown in Figure 11.

[0163] As shown in Figures 13 and 14, this embodiment adds a housing 3 to the battery module shown in Figure 11, arranging each individual battery cell 2 inside the housing 3. A clearance hole 32 is provided on the top plate 31 of the housing, allowing the polar terminals 12 of each individual battery cell 2 to extend. Each individual battery cell 2's polar terminals 12 extend 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 sealing 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 shown in Figure 14, the blocking ring 15 in this embodiment has an L-shaped cross-section. The transverse ring plate is fixed to the area of ​​the upper cover plate 11 of the individual battery cell 2 around the insulating member 14, and the longitudinal ring plate extends into the clearance hole 32 and is sealed to the wall of the clearance hole 32.

[0164] 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.

[0165] 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.

[0166] In Figures 13 and 14, 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.

[0167] In some other embodiments, only an electrolyte shared chamber 35 or a gas shared chamber 36 may be provided.

[0168] As shown in Figure 15, 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.

[0169] Unlike the above embodiments, the top cover assembly for a single battery provided in Embodiments 6 to 9 includes a top cover plate, polar terminals, annular insulating members, and conductive connectors.

[0170] The top cover is an electrical conductor; mounting holes are provided on the top cover; polarity terminals pass through the mounting holes;

[0171] The annular insulating member is an electrical insulator and is sealed and fixed between the polarity terminal and the upper cover plate; a channel is opened on the annular insulating member along its thickness direction;

[0172] The conductive connector is fixed on the polar terminal and located above the annular insulating member. When the temperature reaches the set threshold temperature, the conductive connector deforms and partially fills the channel of the annular insulating member, thereby achieving electrical conductivity between the upper cover plate and the polar terminal.

[0173] The single-cell battery provided in Examples 6 to 9 includes an outer cylinder, an upper cover assembly, a lower cover assembly, and an electrode assembly; the outer cylinder, upper cover assembly, and lower cover assembly are arranged to form a single-cell battery housing, and the electrode assembly is located inside the housing; the upper cover assembly adopts the above-described upper cover assembly, and the electrode tabs of the electrode assembly are electrically connected to the polarity terminals.

[0174] The battery modules provided in Examples 6 to 9 include n individual battery cells arranged in the same direction; the n individual battery cells are electrically connected based on polarity terminals; wherein the individual battery cells are the aforementioned individual battery cells; and n is an integer greater than 1. The electrical connections include parallel connection, series connection, and mixed connection.

[0175] As can be seen from the above description, in Examples 6 to 9, the conductive connector has the following two states:

[0176] First state: When the single cell is in normal working condition, its temperature can be assumed to be T1. The conductive connector is fixed on the polarity terminal and is not connected to the top cover.

[0177] 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 partially fills the channel of the insulating ring component, connecting the upper cover plate and the polar terminal to achieve electrical conduction between the upper cover plate and the polar terminal.

[0178] 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.

[0179] 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.

[0180] 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.

[0181] It should be noted that:

[0182] 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.

[0183] 2. Typically, for conventional square-shell batteries, the top cover plate is provided with two polarity terminals of different polarities. In Examples 6 to 9, the main example is that conductive connectors are fixed on both polarity terminals of different polarities.

[0184] 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 Examples 6 to 9, materials with this property are referred to as temperature-sensitive materials. Temperature-sensitive metal materials or temperature-sensitive conductive polymer materials can be selected.

[0185] 4. The aforementioned channel can be a through hole opened on the annular insulating member, or a notch opened on the annular insulating member, as long as it can be ensured that the electrical connection between the upper cover plate and the polarity terminal is achieved through the channel after the conductive connector is deformed by heat.

[0186] The following describes embodiments 6 to 9 in further detail with reference to the accompanying drawings and specific examples.

[0187] Example 6

[0188] This embodiment is a top cover assembly for a single battery cell, the structure of which is shown in Figures 16, 17 and 18, including a top cover plate 21, polar terminals 22, annular insulating members 24 and conductive connectors 23.

[0189] The upper cover plate 21 is used to enclose the lower cover assembly of the single battery cell and the outer cylinder to form the outer casing of the single battery cell. In this embodiment, the upper cover plate 21 is a rectangular plate made of a conductive metal material, typically aluminum.

[0190] As can be seen from Figures 16 and 17, the polar terminal 22 in this embodiment is a single cell battery terminal, which is taller than the conventional single cell battery terminal.

[0191] In some other embodiments, when the height of the individual battery terminal does not meet the set requirements, a terminal adapter can be connected to the individual battery terminal, and the overall structure of the individual battery terminal and the terminal adapter can be used as the polarity terminal 22 of the individual battery.

[0192] In addition, this embodiment includes two polarity terminals 22, both of which are fixed on the upper cover plate 21. For ease of description, in this embodiment, the two polarity terminals 22 are defined as the first polarity terminal and the second polarity terminal, respectively, and the first polarity terminal and the second polarity terminal serve as the positive and negative polarity terminals of a single cell.

[0193] Referring to Figures 17 and 18, it can be seen that in this embodiment, mounting holes are formed on the upper cover plate 21 corresponding to the positions of the polarity terminal 22. The polarity terminal 22 has a limiting portion 221 and an electrical connection portion 222. The electrical connection portion 222 of the polarity terminal 22 passes through the mounting holes and is fixed to the upper cover plate 21 on one side by an annular insulating member 24. The limiting portion of the polarity terminal 22 is limited on the other side of the upper cover plate 21.

[0194] Insulation between the polarity terminal 22 and the upper cover plate 21 can be achieved by an annular insulating member 24 disposed between the upper cover plate 21 and the polarity terminal 22. The annular insulating member 24 can be an annular insulating layer formed by pouring insulating adhesive between the polarity terminal 22 and the upper cover plate 21, or an insulating sleeve disposed between the polarity terminal 22 and the upper cover plate 21, etc. The material of the annular insulating member 24 can be the insulating material used between the polarity terminal 22 and the upper cover plate 21 in the prior art. Furthermore, the connection method between the annular insulating member 24 and the polarity terminal 22 and the upper cover plate 21 can also adopt relevant existing technologies; this embodiment does not impose specific limitations.

[0195] As can be seen from Figure 18, in this embodiment, at least one through hole 25 is opened in the annular insulating member 24. The through hole 25 penetrates the annular insulating member 24 in the thickness direction. The size of the through hole 25 needs to be guaranteed. At a set threshold temperature, the conductive connector 23 deforms and part of the structure can be filled in the through hole 25 to realize the electrical conduction between the upper cover plate 21 and the polar terminal 22.

[0196] In some other embodiments, as shown in FIG19, a notch 241 can be opened at the edge of the annular insulating member 24; at a set threshold temperature, the conductive connector 23 deforms, and part of the structure can be filled in the notch 241 to achieve electrical conduction between the upper cover plate 21 and the polar terminal 22.

[0197] As can be seen from Figures 16, 17 and 18, there are two conductive connectors 23 in this embodiment, both of which are annular plates. They are respectively sleeved and fixed on the first polarity terminal and the second polarity terminal, and there is a certain distance between them and the upper cover plate 21. This distance needs to ensure that the conductive connectors 23 and the upper cover plate 21 remain insulated when the single cell 27 is in normal working condition.

[0198] In order to improve the installation stability of the conductive connector 23, the conductive connector 23 is sleeved on the polar terminal 22, and its bottom surface is pressed against the annular insulating member 24. In addition, a stepped structure can be provided on the polar terminal 22, with the stepped surface flush with the upper end surface of the annular insulating member 24, and the bottom surface of the conductive connector 23 is pressed against both the upper end surface of the annular insulating member 24 and the stepped surface.

[0199] In some other embodiments, other shapes may be used, such as a semi-circular metal plate, which is fixed on the polar terminal 22, but its stability is weaker than that of this embodiment.

[0200] In addition, this embodiment uses an annular plate, which is easier to fix to the polar terminal 22 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 polar terminal 22 and part of it fills any through hole and contacts the upper cover plate 21, the electrical connection between the polar terminal 22 and the upper cover plate 21 can be realized, which has high connection reliability.

[0201] In this embodiment, the conductive connector 23 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 22 and part flowing into the through hole 25 of the annular insulating member 24 under the action of gravity, connecting to the upper cover plate 21, thereby realizing electrical conduction between the polar terminal 22 and the upper cover plate 21, as shown in Figure 20.

[0202] In this embodiment, the temperature threshold corresponds to the temperature that the polarity terminal 22 will reach when a single cell experiences thermal runaway. The corresponding conductive connector 23 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 used.

[0203] In 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 (e.g., battery voltage, load size, resistance of components in the circuit), and ambient environmental parameters (e.g., ambient temperature, humidity). 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.

[0204] In other embodiments, other temperature-sensitive conductors may be selected. These conductors expand when heated to a set threshold temperature, and part of their structure penetrates through the through hole to contact the upper cover plate 21, thereby achieving electrical connection between the polarity terminal 22 and the upper cover plate 21.

[0205] In this embodiment, a first opening element can also be provided on the upper cover plate 21, which is located between the two polarity terminals 22. Under the action of external force or electrolyte, the first opening element can detach from the upper cover plate 21 of the single cell and form a through hole in the upper cover plate 21 that penetrates the inner cavity of the outer casing. The first opening element adopts an existing structure, such as the first opening element disclosed in Chinese Patent CN221327991U, the sealing device disclosed in Chinese Patent CN117476997A, and the opening device disclosed in CN117477117A.

[0206] Example 7

[0207] This embodiment is a single-cell battery, the structure of which is shown in Figures 21 and 22. It includes an outer casing and an electrode assembly and electrolyte located inside the outer casing. The outer casing is formed by an outer cylinder, a lower cover assembly, and an upper cover assembly as shown in Embodiment 6. The first polarity terminal and the second polarity terminal on the upper cover assembly are electrically connected to the positive and negative electrodes of the electrode assembly, respectively (the connection structure is not shown in Figure 22).

[0208] In this embodiment, the lower cover assembly includes a lower cover plate 26, and a second opening member 261 may also be provided on the lower cover plate 26. This second opening member 261 can detach from the lower cover plate 26 of the individual battery 27 under external force or electrolyte action, and forms a through hole 25 in the lower cover plate 26 that penetrates the inner cavity of the outer casing. The second opening member 261 is also a conventional structure, for example, it can adopt the opening member disclosed in Chinese Patent CN221327991U, the sealing device disclosed in Chinese Patent CN117476997A, and the opening device disclosed in CN117477117A, etc. The structure of the second opening member 261 can be the same as or different from the first opening member.

[0209] Example 8

[0210] As shown in Figure 23, this embodiment is a battery module, including 12 individual battery cells 27 arranged in the same direction as in Embodiment 7. In some other embodiments, the number of individual battery cells 27 can be adjusted according to actual needs. The 12 individual battery cells 27 are electrically connected based on polarity terminals 22, and this electrical connection can be parallel, series, or a combination of both.

[0211] When each individual cell 27 has a second opening piece 261 on its lower cover plate 26, the second opening piece 261 of each individual cell 27 can be opened, and a hollow component can be used to connect the inner cavities of all individual cells 27 to achieve electrolyte sharing, reduce the differences between individual cells 27, and optimize the cycle performance of the battery module. It should be noted that when each individual cell 27 achieves electrolyte sharing, the individual cells 27 are preferably connected in parallel.

[0212] When each individual battery cell 27 has a first opening component on its upper cover plate 21, the first opening component of each individual battery cell 27 can be opened, and another hollow component can be used to connect the inner cavities of all individual batteries 27 to achieve gas sharing, gas balance, and further optimize the cycle performance of the battery module.

[0213] Referring to Figure 20, in the event of thermal runaway of any single cell 27 in the battery module, the temperature of the conductive connector 23 of the single cell 27 rises to or exceeds a set threshold temperature, causing the conductive connector 23 to be heated and become molten. Part of the molten material flows into the through hole 25 of the annular insulating member 24 and connects between the upper cover plate 21 and the polar terminal 22, thereby realizing the electrical connection between the upper cover plate 21 and the polar terminal 22. This makes the single cell 27 a resistor in the circuit of the entire battery module. At least a portion of the discharge current of the single cell 27 that has not experienced thermal runaway flows through the upper cover plate 21 of the single cell 27 to continue to supply power to the load.

[0214] Example 9

[0215] This embodiment is another type of battery module. Its structure differs from that of embodiment 8. The battery module in this embodiment also has a housing 28, and the specific structure is shown in Figures 24, 25 and 26.

[0216] As shown in Figures 24 to 26, this embodiment adds a housing 28 to the battery module shown in Figure 23, arranging each individual battery cell 27 inside the housing 28. A clearance hole 212 is provided on the top plate 281 of the housing, allowing the polar terminals 22 of each individual battery cell 27 to extend. Each individual battery cell 27's polar terminals 22 extend out of the corresponding clearance hole 212, and the area of ​​the top plate 281 corresponding to the clearance hole 212 is fixedly sealed to the upper cover plate 21 of the individual battery cell 27. This embodiment uses a sealing connector 211 to achieve the fixed sealing between the area of ​​the top plate 281 corresponding to the clearance hole 212 and the upper cover plate 21 of the individual battery cell 27. Specifically, as shown in Figure 26, the sealing connector 211 in this embodiment is a hollow tube with an annular plate on the inner side of its bottom end. The annular plate and the area of ​​the upper cover plate 21 of the individual battery cell 27 surrounding the annular insulating member 24 are fixed. The hollow tube extends into the clearance hole 212, and its outer wall is sealed to the wall of the clearance hole 212.

[0217] A support member 213 extending in the x-direction is provided between the bottom plate 282 of the outer casing and each individual battery cell 27 to form a liquid channel, serving as an electrolyte sharing chamber 29. When the lower cover plate 26 of each individual battery cell 27 has a second opening piece 261, the second opening piece 261 of the lower cover plate 26 of each individual battery cell 27 can be opened, and the inner cavities of all individual battery cells 27 can be connected based on the electrolyte sharing chamber 29, realizing electrolyte sharing, reducing the differences between individual battery cells 27, and optimizing the cycle performance of the battery module. It should be noted that when the individual battery cells 27 realize electrolyte sharing, the individual battery cells 27 are preferably connected in parallel.

[0218] On the top plate 281 of the outer casing, there is a boss extending in the x direction. A gas channel is opened on the boss. The gas channel is connected to the inner cavity of the outer casing 28 and serves as a gas sharing chamber 210, which is connected to the gas area of ​​the inner cavity of each individual battery cell 27. When gas is generated in the inner cavity of the individual battery cell 27, the inner cavity of the gas channel can also serve as a gas containing cavity to alleviate the problem of the outer casing 28 swelling caused by gas generation.

[0219] In some other embodiments, only an electrolyte sharing chamber 29 or a gas sharing chamber 210 may be provided.

[0220] As shown in Figure 27, in the battery module, if any single cell 27 experiences thermal runaway, the temperature of the conductive connector 23 of that single cell 27 rises to or exceeds a set threshold temperature, causing the conductive connector 23 to be heated and become molten. The molten material flows through the through hole 25 (Figures 26 and 27 use the through hole 25 as an example) to the upper cover plate 21, connecting the upper cover plate 21 and the polar terminal 22. This achieves an electrical connection between the upper cover plate 21 and the polar terminal 22, making the single cell 27 a resistor in the circuit of the entire battery module. At least a portion of the discharge current of the single cell 27 that has not experienced thermal runaway flows through the upper cover plate 21 of the single cell 27 to continue supplying power to the load.

[0221] Unlike the embodiments described above, the top cover assembly for a single battery provided in Embodiments 10 to 15 includes a polar terminal and a top cover plate, a connecting plate (which serves as a conductive connector), and an insulating plate stacked sequentially. In the stacking direction, the top cover plate and the insulating plate have interconnecting mounting holes. The polar terminal passes through the mounting holes and is sealed to the top cover plate. Both the top cover plate and the connecting plate are electrical conductors, and the insulating plate is an electrical insulator. The top cover plate is insulated from the polar terminal, and a channel is provided between the connecting plate and the polar terminal.

[0222] When the temperature reaches the set threshold temperature, the connecting plate deforms due to heat, and part of the structure fills the channel. It is connected between the polar terminal and the upper cover plate through the channel to achieve electrical conduction between the upper cover plate and the polar terminal.

[0223] The single-cell battery provided in Examples 10 to 15 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-cell battery housing, and the electrode assembly is located inside the housing; the upper cover assembly adopts the above-described upper cover assembly, and the electrode tabs of the electrode assembly are electrically connected to the polarity terminals.

[0224] The battery modules provided in Examples 10 to 15 include n individual battery cells arranged in the same direction; the n individual battery cells are electrically connected based on polarity terminals; wherein the individual battery cells are the aforementioned individual battery cells; and n is an integer greater than 1. The electrical connections include parallel connection, series connection, and mixed connection.

[0225] As can be seen from the above description, in Embodiments 10 to 15, the connecting plate has the following two states:

[0226] First state: When the single cell is in normal working condition, its temperature can be assumed to be T1. The connecting plate is fixed between the top cover plate and the insulating plate and is not connected to the polarity terminal.

[0227] Second state: When the temperature of a single cell is T2, where T2 > T1; the temperature of the connecting plate reaches the set threshold temperature. At this temperature, the connecting plate deforms, and part of the structure fills the channel between the connecting plate and the polar terminal, connecting the upper cover plate and the polar terminal, thus realizing the electrical conduction between the upper cover plate and the polar terminal.

[0228] 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.

[0229] In the battery module, when a single cell experiences thermal runaway, the temperature of the connecting plate of that single cell rises to or exceeds a set threshold temperature, causing the connecting plate to deform due to heat. It then connects to the top cover and the polar terminals through a channel, thereby achieving an electrical connection between the top cover and the polar terminals. This makes 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 in the entire battery module that have not experienced thermal runaway flows through the top cover assembly of that single cell to continue supplying power to the load.

[0230] Therefore, it can be seen that even if a single cell in the battery module of Examples 10 to 15 experiences thermal runaway, the entire battery module can still continue to operate normally and supply power to the load.

[0231] It should be noted that:

[0232] 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.

[0233] 2. The deformation of the connecting plate upon heating can be understood as thermal expansion, or as a change in state, such as from a solid to a molten state. In Examples 10 to 15, materials with this property are referred to as temperature-sensitive materials. Temperature-sensitive metal materials or temperature-sensitive conductive polymer materials can also be selected.

[0234] 3. The aforementioned channel can be a through hole opened on the insulating plate, or it can be a gap between the insulating plate and the polarity terminal. As long as it can be ensured that the electrical connection between the upper cover plate and the polarity terminal is achieved through the channel after the connecting plate is deformed by heat.

[0235] 4. The connecting plate mentioned above can be an annular plate sandwiched between the upper cover plate and the insulating plate. The polarity terminal passes through the mounting hole and also through the inner hole of the annular plate. There is a gap between the annular plate and the inner hole wall to ensure the insulation between the two. The connecting plate mentioned above can also be a rectangular plate or a circular plate sandwiched between the upper cover plate and the insulating plate. The rectangular plate or circular plate needs to avoid the mounting hole position to ensure that the polarity terminal can pass through the mounting hole.

[0236] The following describes embodiments 10 to 15 in further detail with reference to the accompanying drawings and specific examples.

[0237] Example 10

[0238] This embodiment is a top cover assembly 311 for a single battery cell 32, the structure of which is shown in Figures 28, 29 and 30. It includes a polar terminal 312 and a top cover plate 3111, a connecting plate 3112 (which serves as a conductive connector) and an insulating plate 3113 stacked in sequence. That is, the connecting plate 3112 is sandwiched between the top cover plate 3111 and the insulating plate 3113.

[0239] The upper cover assembly 311 is used to enclose the lower cover assembly of the single cell 32 and the outer cylinder to form the outer shell of the single cell 32.

[0240] As can be seen from Figures 28 and 29, the polarity terminal 312 in this embodiment is a single cell 32 terminal post, which is taller than the conventional single cell 32 terminal post.

[0241] In some other embodiments, when the height of the terminal post of the single battery cell 32 does not meet the set requirements, a terminal post adapter can be connected to the terminal post of the single battery cell 32, and the overall structure of the terminal post of the single battery cell 32 and the terminal post adapter is used as the polarity terminal 312 of the single battery cell 32.

[0242] In this embodiment, both the top cover plate 3111 and the insulating plate 3113 are rectangular plates. The top cover plate 3111 is made of a conductive metallic material, typically aluminum. The insulating plate 3113 is made of an insulating material, typically high-temperature resistant plastic or rubber. Here, high temperature generally refers to the thermal runaway temperature of the battery.

[0243] Mounting holes that communicate with each other are made on the upper cover plate 3111 and the insulating plate 3113 corresponding to the positions of the polarity terminals 312. For ease of description, in this embodiment, the mounting holes on the upper cover plate 3111 are defined as the first mounting holes 313, and the mounting holes on the insulating plate 3113 are defined as the second mounting holes 314.

[0244] The number of connecting plates 3112 is the same as the number of polar terminals 312, and the connecting plates 3112 and polar terminals 312 correspond one-to-one. In this embodiment, two polar terminals 312 are used as an example. For ease of description, in this embodiment, the two polar terminals 312 are defined as the first polar terminal 3121 and the second polar terminal 3122, respectively. The first polar terminal 3121 and the second polar terminal 3122 are respectively used as the positive and negative polar terminals of the single cell 32.

[0245] As can be seen from Figure 30, in this embodiment, the connecting plate 3112 is an annular plate, sandwiched between the upper cover plate 3111 and the insulating plate 3113, and the inner hole of the connecting plate 3112 is in communication with the first mounting hole 313 and the second mounting hole 314.

[0246] In this embodiment, the connecting plate 3112 is made of a low-melting-point metal. The melting point of the low-melting-point metal is less than or equal to a set threshold temperature. At the set temperature threshold, the metal becomes molten.

[0247] In this embodiment, the temperature threshold corresponds to the temperature that the upper cover assembly will reach when the single cell 32 experiences thermal runaway. The corresponding connecting plate 3112 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.

[0248] 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 32 (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.

[0249] In some other embodiments, other temperature-sensitive conductors may be selected, which expand when heated at a set threshold temperature.

[0250] Referring to Figures 29 and 30, it can be seen that the polarity terminal 312 in this embodiment has a limiting portion 3123 and an electrical connection portion 3124. The electrical connection portion 3124 of the polarity terminal 312 passes sequentially through the second mounting hole 314, the inner hole of the connecting plate 3112, and the first mounting hole 313, and is fixed to the upper cover plate 3111 on the side away from the insulating plate 3113 by an insulating member 315. The limiting portion 3123 of the polarity terminal 312 is limited to the side of the insulating plate 3113 away from the upper cover plate 3111.

[0251] The insulating component 315 serves both to insulate the polarity terminal 312 from the upper cover plate 3111 and to provide a fixed seal between them. The insulating component 315 can be a ring-shaped insulating layer formed by pouring insulating adhesive between the polarity terminal 312 and the upper cover plate 3111, or an insulating sleeve disposed between them. The insulating component 315 can be made of the same insulating material used between the polarity terminal 312 and the upper cover assembly 311 in the prior art. Furthermore, the connection method between the insulating component 315 and the polarity terminal 312 and the upper cover plate 3111 can also employ relevant existing technologies; this embodiment does not impose specific limitations.

[0252] The electrical connection portion 3124 of the polarity terminal 312 has a first annular gap 319 between it and the inner hole of the connecting plate 3112 to ensure the insulation between the polarity terminal 312 and the connecting plate 3112 when the single cell 32 is in normal working condition.

[0253] As can be seen from Figures 29 and 30, the polar terminal 312 in this embodiment includes a base 3125 and a column 3126. The column 3126 is fixedly connected to the base 3125. The portion of the base 3125 that extends radially out of the column 3126 forms a limiting portion 3123. The end of the column 3126 away from the base 3125 forms an electrical connection portion 3124.

[0254] In this embodiment, the base 3125 and the column 3126 are an integral structure, and the polar terminal 312 can be obtained by die casting or machining. In other embodiments, the base 3125 and the column 3126 can be separate structures. In this case, the base 3125 can be obtained by stamping, and the column 3126 can be obtained by die casting or machining. The obtained base 3125 and column 3126 are then fixed to obtain the polar terminal 312.

[0255] For the integrated base 3125 and column 3126, both are made of the same material, such as conductive materials like aluminum or copper. For the separate base 3125 and column 3126, their materials can be the same or different. When the materials are different, the base 3125 can be made of copper and the column 3126 can be made of aluminum; or the base 3125 can be made of aluminum and the column 3126 can be made of copper.

[0256] In this embodiment, the base 3125 and the column 3126 of the split structure can be fixed by friction welding (i.e., the column 3126 and the base 3125 are fixed by friction welding) or by riveting. Of course, other methods can also be used for fixing, but this embodiment does not limit this.

[0257] As can be seen from Figures 29 and 30, in this embodiment, a through hole 316 is provided on the insulating plate 3113. The through hole 316 penetrates the insulating plate 3113 in the thickness direction and is located directly above the polarity terminal 3122 limiting part 3123.

[0258] In this embodiment, there are 4 through holes 316. In some other embodiments, the number of through holes 316 can be adjusted.

[0259] As shown in Figure 31, in the case of thermal runaway of a single cell 32 in the battery module, the temperature of the connecting plate 3112 in the upper cover assembly 311 of the single cell 32 rises to or exceeds a set threshold temperature, causing the connecting plate 3112 to become molten. Under the action of gravity, the molten connecting plate 3112 flows into the through hole 316 and is connected between the upper cover plate 3111 and the polarity terminal 312 limiting part 3123 through the through hole 316. This realizes the electrical connection between the upper cover plate 3111 and the polarity terminal 312, making the single cell 32 a resistor in the circuit of the entire battery module. At least a portion of the discharge current of the single cell 32 that has not experienced thermal runaway flows through the upper cover assembly 311 of the single cell 32 to continue to supply power to the load.

[0260] It should be noted that the molten connecting plate 3112 may also flow into the first annular gap 319, connecting the electrical connection area of ​​the polarity terminal located in the mounting hole to the upper cover plate, thus achieving electrical connection between the upper cover plate 3111 and the polarity terminal 312.

[0261] In other embodiments, the connecting plate 3112 can also adopt other structural forms. For example, as shown in Figures 32 and 33, it can be a rectangular plate or a circular plate sandwiched between the upper cover plate 3111 and the insulating plate 3113. Multiple through holes 316 are opened at the positions corresponding to the insulating plate. When the temperature of the connecting plate 3112 in the upper cover assembly 311 of the single battery 32 rises to or exceeds a set threshold temperature, the connecting plate 3112 becomes molten. Under the action of gravity, the molten connecting plate 3112 flows into the through holes 316 and is connected between the upper cover plate 3111 and the polarity terminal 312 limiting part 3123 through the through holes 316. This also realizes the electrical connection between the upper cover plate 3111 and the polarity terminal 312, so that the single battery 32 becomes a resistor in the circuit of the entire battery module. At least a part of the discharge current of the single battery 32 that has not experienced thermal runaway in the entire battery module flows through the upper cover assembly 311 of the single battery 32 to continue to supply power to the load.

[0262] In some other embodiments, when the connecting plate is a thermally expandable temperature-sensitive conductor, the temperature of the connecting plate 3112 in the upper cover assembly 311 of the single cell 32 rises to or exceeds a set threshold temperature, causing the connecting plate 3112 to expand due to heat. The expanded portion passes through the through hole 316 or the first annular gap 319 and connects between the upper cover plate 3111 and the polarity terminal 312 limiting portion 3123. This also realizes the electrical connection between the upper cover plate 3111 and the polarity terminal 312, making the single cell 32 a resistor in the circuit of the entire battery module. At least a portion of the discharge current of the single cell 32 that has not experienced thermal runaway flows through the upper cover assembly 311 of the single cell 32 to continue supplying power to the load.

[0263] In this embodiment, a first opening element can also be provided on the top cover assembly 311, which is located between the two polarity terminals 312. Under the action of external force or electrolyte, the first opening element can detach from the top cover assembly 311 of the single cell 32 and form a through hole 316 in the top cover assembly 311 that penetrates the inner cavity of the outer casing. The first opening element adopts an existing structure, such as the first opening element disclosed in Chinese Patent CN221327991 U, the sealing device disclosed in Chinese Patent CN117476997A, and the opening device disclosed in CN117477117A.

[0264] Example 11

[0265] This embodiment is also a top cover assembly 311 for a single battery 32, the structure of which is shown in Figure 34. Unlike embodiment 10, the diameter of the second mounting hole 314 on the insulating plate 3113 in this embodiment is larger than the diameter of the first mounting hole 313 on the top cover plate 3111. After the polarity terminal 312 electrical connection part 3124 passes through the second mounting hole 314, there is a second annular gap 317 between it and the insulating plate 3113.

[0266] As shown in Figure 35, in the case of thermal runaway of a single cell 32 in the battery module, the temperature of the connecting plate 3112 in the upper cover assembly 311 of the single cell 32 rises to or exceeds a set threshold temperature, causing the connecting plate 3112 to become molten. Under the action of gravity, the molten connecting plate 3112 flows into the second annular gap 317 and is connected between the upper cover plate 3111 and the polarity terminal 312 limiting part 3123 through the second annular gap 317. This realizes the electrical connection between the upper cover plate 3111 and the polarity terminal 312, making the single cell 32 a resistor in the circuit of the entire battery module. At least a portion of the discharge current of the single cell 32 that has not experienced thermal runaway flows through the upper cover assembly 311 of the single cell 32 to continue to supply power to the load.

[0267] It should be noted that the molten connecting plate 3112 may also contact the electrical connection portion 3124 area located in the mounting hole within the second annular gap 317, thereby achieving electrical connection between the upper cover plate 3111 and the polarity terminal 312.

[0268] Example 12

[0269] This embodiment is also a cover assembly for a single battery cell, the structure of which is shown in Figures 36 and 37. Unlike the above embodiments, this embodiment adds an insulating sealing ring 318 between the cover plate 3111 and the polarity terminal 3122 limiting part 3123.

[0270] As shown in Figure 36, taking the addition of an insulating sealing ring 318 to the upper cover assembly 311 in Embodiment 10 as an example;

[0271] Based on embodiment 10, this embodiment adjusts the diameter of the second mounting hole 314 so that the diameter of the second mounting hole 314 is larger than the diameter of the first mounting hole 313; after the polar terminal 312 electrical connection part 3124 passes through the second mounting hole 314, the annular gap between it and the insulating plate 3113 serves as the installation space for the insulating sealing ring.

[0272] An insulating sealing ring 318 is fitted onto the polar terminal 312. The outer ring surface of the insulating sealing ring 318 is in close contact with the wall of the second mounting hole 314. The top and bottom surfaces of the insulating sealing ring 318 abut against the upper cover plate 3111 and the limiting part 3123 of the polar terminal 312, respectively, thereby clamping the insulating sealing ring 318 between the upper cover plate 3111 and the limiting part 3123 of the polar terminal 312. In this way, the sealing performance between the polar terminal 312 and the upper cover plate 3111 can be further improved.

[0273] As shown in Figure 37, taking the addition of an insulating sealing ring 318 to the upper cover assembly 311 in Embodiment 11 as an example;

[0274] An insulating sealing ring 318 is fitted onto the polar terminal 312, with a gap reserved between the outer ring surface of the insulating sealing ring 318 and the wall of the second mounting hole 314 to facilitate the flow of the molten connecting plate 3112 into the gap, thereby achieving electrical connection between the upper cover plate 3111 and the polar terminal 312. The top and bottom surfaces of the insulating sealing ring 318 abut against the upper cover plate 3111 and the limiting part 3123 of the polar terminal 312, respectively, thereby clamping the insulating sealing ring 318 between the upper cover plate 3111 and the limiting part 3123 of the polar terminal 312. In this way, the sealing performance between the polar terminal 312 and the upper cover plate 3111 can be further improved.

[0275] In addition, under normal operating conditions of the single cell 32, the above-mentioned insulating sealing ring 318 can further improve the insulation performance between the upper cover plate 3111, the connecting plate 3112 and the polar terminal 312.

[0276] Example 13

[0277] This embodiment is a single-cell battery, the structure of which is shown in Figure 38. It includes an outer casing and an electrode assembly and an electrolyte located inside the outer casing. The outer casing is formed by an outer cylinder, a lower cover assembly, and an upper cover assembly 311 as described in the above embodiment. The first polarity terminal 3121 and the second polarity terminal 3122 on the upper cover assembly 311 are electrically connected to the positive and negative terminals of the electrode assembly, respectively.

[0278] In this embodiment, the lower cover assembly includes a lower cover plate 321, and a second opening member 322 may be provided on the lower cover plate 321. This second opening member 322 can detach from the lower cover plate 321 of the individual battery 32 under external force or electrolyte action, and forms a through hole in the lower cover plate 321 that penetrates the inner cavity of the outer casing. The second opening member 322 can also be a conventional structure, for example, it can adopt the opening member disclosed in Chinese Patent CN221327991U, the sealing device disclosed in Chinese Patent CN117476997A, and the opening device disclosed in CN117477117A, etc. The structure of the second opening member 322 can be the same as or different from the first opening member.

[0279] Example 14

[0280] As shown in Figure 39, this embodiment is a battery module, including 12 individual battery cells 32 arranged in the same direction as in Embodiment 13. In some other embodiments, the number of individual battery cells 32 can be adjusted according to actual needs. The 12 individual battery cells 32 are electrically connected based on polarity terminals 312, and this electrical connection can be parallel, series, or a combination of both.

[0281] When each individual cell 32 has a second opening piece 322 on its lower cover plate 321, the second opening piece 322 of each individual cell 32 can be opened, and a hollow component can be used to connect the inner cavities of all individual cells 32 to achieve electrolyte sharing, reduce the differences between individual cells 32, and optimize the cycle performance of the battery module. It should be noted that when each individual cell 32 achieves electrolyte sharing, the individual cells 32 are preferably connected in parallel.

[0282] When each individual cell 32 cover assembly 311 has a first opening piece, the first opening piece of each individual cell 32 cover assembly 311 can be opened, and another hollow component can be used to connect the inner cavities of all individual cells 32 to achieve gas sharing, gas balance, and further optimize the cycle performance of the battery module.

[0283] In the event of thermal runaway of any single cell 32 in the battery module, the temperature of the connecting plate 3112 of the single cell 32 rises to or exceeds a set threshold temperature, causing the connecting plate 3112 to be heated and become molten. The molten material flows through the through hole 316 or the second annular gap 317 to the polar terminal 312, connecting the upper cover assembly 311 and the polar terminal 312. This achieves an electrical connection between the upper cover assembly 311 and the polar terminal 312, making the single cell 32 a resistor in the circuit of the entire battery module. At least a portion of the discharge current of the single cell 32 that has not experienced thermal runaway flows through the upper cover assembly 311 of the single cell 32 to continue supplying power to the load.

[0284] Example 15

[0285] This embodiment is another type of battery module. The structure of this battery module is different from that of embodiment 14. In this embodiment, the battery module also has a housing 33. The specific structure is shown in Figures 40, 41 and 42.

[0286] Figures 40 and 41 illustrate an example of adding a housing 33 to the battery module shown in Figure 39.

[0287] As shown in Figures 40 to 42, this embodiment adds a housing 33 to the battery module shown in Figure 39, arranging each individual battery cell 32 inside the housing 33. A clearance hole 332 is provided on the top plate 331 of the housing, allowing the polarity terminals 312 of each individual battery cell 32 to extend. The polarity terminals 312 of each individual battery cell 32 extend out of the corresponding clearance hole 332, and the area of ​​the top plate 331 of the housing corresponding to the clearance hole 332 is fixedly sealed to the upper cover plate 3111 of the individual battery cell 32. In this embodiment, a sealing connector 337 is used to achieve a fixed seal between the area of ​​the outer shell top plate 331 corresponding to the clearance hole 332 and the upper cover plate 3111 of the single cell 32. As shown in Figure 42, the sealing connector 337 in this embodiment is a hollow tube with an annular plate on the inner side of the bottom end. The annular plate and the area of ​​the upper cover plate 3111 of the single cell 32 around the insulating component 315 are fixed. The hollow tube extends into the clearance hole 332, and its outer wall is sealed to the wall of the clearance hole 332.

[0288] A support member 334 extending in the x-direction is provided between the bottom plate 333 of the outer casing and each individual battery cell 32 to form a liquid channel, serving as an electrolyte sharing chamber 335. When the lower cover plate 321 of each individual battery cell 32 has a second opening piece 322, the second opening piece 322 of the lower cover plate 321 of each individual battery cell 32 can be opened, and the inner cavities of all individual battery cells 32 are connected based on the electrolyte sharing chamber 335, realizing electrolyte sharing, reducing the differences between individual battery cells 32, and optimizing the cycle performance of the battery module. It should be noted that when the individual battery cells 32 realize electrolyte sharing, the individual battery cells 32 are preferably connected in parallel.

[0289] In Figures 40 and 41, a boss extending along the x-direction is provided on the top plate 331 of the outer casing. A gas channel is opened on the boss, which is connected to the inner cavity of the outer casing 33 and serves as a gas sharing chamber 336, which is connected to the gas area of ​​the inner cavity of each individual battery cell 32. When gas is generated in the inner cavity of the individual battery cell 32, the inner cavity of the gas channel can also serve as a gas containing cavity to alleviate the problem of the outer casing 33 bulging caused by gas generation.

[0290] In some other embodiments, only an electrolyte sharing chamber 335 or a gas sharing chamber 336 may be provided.

[0291] As shown in Figure 43, in the event of thermal runaway of any single cell 32 in the battery module, the temperature of the connecting plate 3112 of the single cell 32 rises to or exceeds a set threshold temperature, causing the connecting plate 3112 to be heated and become molten. The molten current flows through the through hole 316 (Figures 42 and 43 use the through hole 316 as an example) to the polarity terminal 312 limiting part 3123, connecting the upper cover plate 3111 and the polarity terminal 312. This achieves the electrical connection between the upper cover assembly 311 and the polarity terminal 312, making the single cell 32 a resistor in the circuit of the entire battery module. At least a portion of the discharge current of the single cell 32 that has not experienced thermal runaway flows through the upper cover assembly 311 of the single cell 32 to continue supplying power to the load.

Claims

1. A cover assembly for a single-cell battery, comprising an upper cover plate with electrical conductors and polar terminals disposed on the upper cover plate, the polar terminals being insulated from the upper cover plate; characterized in that: It also includes conductive connectors, which deform when the temperature reaches a set threshold temperature, thus achieving electrical conductivity between the top cover and the polar terminals.

2. The top cover assembly for a single battery cell according to claim 1, characterized in that: The conductive connector is fixed to the upper cover plate or polarity terminal.

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

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

5. The top cover assembly for a single battery cell according to claim 4, 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.

6. The top cover assembly for a single battery cell according to claim 4, 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.

7. The cover assembly for a single-cell battery according to any one of claims 4 to 6, 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.

8. The top cover assembly for a single battery cell according to claim 2, characterized in that: The top cover is equipped with the first package opening component.

9. The top cover assembly for a single battery cell according to claim 1, characterized in that: It also includes ring-shaped insulating components; Mounting holes are provided on the top cover; polarity terminals pass through the mounting holes; An annular insulating member is sealed and fixed between the polarity terminal and the upper cover plate; a channel is opened on the annular insulating member along its thickness direction; The conductive connector is fixed on the polar terminal and located above the annular insulating member. When the temperature reaches the set threshold temperature, the conductive connector deforms and partially fills the channel of the annular insulating member, thereby achieving electrical conductivity between the upper cover plate and the polar terminal.

10. The top cover assembly for a single battery cell according to claim 9, characterized in that: The channel is at least one through hole formed on the annular insulating member.

11. The cover assembly for a single battery cell according to claim 9 or 10, characterized in that: The conductive connector is a metal component.

12. The top cover assembly for a single battery cell according to claim 11, characterized in that: The melting point of the metal component is less than or equal to a set threshold temperature.

13. The top cover assembly for a single battery cell according to claim 12, characterized in that: The metal component is a ring-shaped metal plate that is sleeved and fixed on the polarity terminal.

14. The top cover assembly for a single battery cell according to claim 9, characterized in that: The top cover is equipped with the first package opening component.

15. The top cover assembly for a single battery cell according to claim 1, characterized in that: It also includes an insulating plate; the conductive connector is a connecting plate; the upper cover plate, the connecting plate and the insulating plate are stacked in sequence, and in the stacking direction, the upper cover plate and the insulating plate have mutually penetrating mounting holes; The polarity terminal passes through the mounting hole and is fixedly sealed between the upper cover plate; The insulating board is an electrical insulator; A channel is provided between the connecting plate and the polarity terminal; When the temperature reaches the set threshold temperature, the connecting plate deforms due to heat, and part of the structure fills the channel, realizing electrical conduction between the top cover and the polarity terminal.

16. The cover assembly for a single battery cell according to claim 15, characterized in that: The polarity terminal includes a limiting part and an electrical connection part; the electrical connection part of the polarity terminal passes through the mounting hole and is fixedly sealed between the terminal and the upper cover plate, and the electrical connection part is located on the side of the upper cover plate, while the limiting part is limited on the side of the insulating plate.

17. The top cover assembly for a single battery cell according to claim 16, characterized in that: The channel is at least one through hole formed on the insulating plate, the through hole penetrating the insulating plate along the thickness direction of the insulating plate; and the through hole is located directly above the polarity terminal limiting part; When the temperature reaches the set threshold temperature, the connecting plate deforms, and part of the structure fills the through hole, connecting between the polarity terminal limiting part and the upper cover plate, so as to realize the electrical conduction between the upper cover plate and the polarity terminal.

18. The top cover assembly for a single battery cell according to claim 16, characterized in that: The diameter of the mounting holes on the insulating plate is larger than the diameter of the mounting holes on the upper cover plate; The channel is the second annular gap formed between the polar terminal through the mounting hole and the insulating plate; When the temperature reaches the set threshold temperature, the connecting plate deforms, and part of the structure fills the second annular gap, connecting between the polar terminal and the upper cover plate, thereby achieving electrical conductivity between the upper cover plate and the polar terminal.

19. The cover assembly for a single-cell battery according to any one of claims 15 to 18, characterized in that: The connecting plate is a metal plate; the melting point of the metal plate is less than or equal to a set threshold temperature.

20. The top cover assembly for a single battery cell according to claim 19, characterized in that: The metal plate is an annular metal plate; the polar terminal passes through the inner hole of the annular metal plate and has a gap between it and the inner hole.

21. The top cover assembly for a single battery cell according to claim 20, characterized in that: It also includes an insulating sealing ring; the insulating sealing ring is sleeved on the polar terminal and clamped between the upper cover plate and the polar terminal limiting part.

22. The cover assembly for a single battery cell according to claim 15, characterized in that: The top cover assembly has a first opening component.

23. A single-cell battery, comprising an outer casing, an upper cover assembly, a lower cover assembly, and an electrode assembly; the outer casing, the upper cover assembly, and the lower cover assembly enclose a single-cell battery housing, and the electrode assembly is located within the housing; characterized in that: The top cover assembly adopts the top cover assembly for a single cell as described in any one of claims 1 to 22, wherein the polarity terminal is electrically connected to the tab of the electrode assembly.

24. The single-cell battery according to claim 23, characterized in that: The lower cover assembly includes a lower cover plate and a second opening component disposed on the lower cover plate.

25. A battery module, characterized in that: It includes n individual cells arranged in the same direction; wherein the individual cells are the individual cells described in claim 23 or 24; and n is an integer greater than 1.

26. The battery module according to claim 25, 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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