Single battery and battery pack

Abstract

The invention discloses a single battery and a battery pack, and belongs to the field of batteries. The single battery has a first direction, and comprises a shell with an opening; the top cover assembly comprises a cover plate assembly and a pole assembly, the cover plate assembly comprises a cover plate, a plastic part and a first isolation part, the cover plate is connected to the shell and covers the opening, the cover plate is provided with a mounting hole, at least part of the pole assembly penetrates through the mounting hole, the pole assembly is connected with the pole lug, and the pole lug is located in the shell; the cover plate is provided with an inner surface facing the interior of the shell, the plastic part is arranged on the inner surface, the first isolation part is located between the plastic part and the inner surface, and in the first direction, the first projection of the electrode lug on the inner surface and the second projection of the first isolation part on the inner surface at least partially coincide.

Description

Technical Field

[0001] This application belongs to the field of battery technology, specifically relating to a single cell battery and a battery pack. Background Technology

[0002] With the development of technology, the use of new energy vehicles is increasing. Typically, new energy vehicles are equipped with battery packs that provide power, enabling the vehicle to move. In related technologies, battery packs contain individual cells. However, in these technologies, when an individual cell experiences thermal runaway, it can easily lead to a short circuit, thereby affecting the safety of the entire battery pack. Summary of the Invention

[0003] This application aims to provide a single cell and a battery pack that at least solves the problem that when a single cell undergoes thermal runaway, it can easily lead to a short circuit in the single cell, thereby affecting the safety of the battery pack.

[0004] To solve the above-mentioned technical problems, this application is implemented as follows: In a first aspect, embodiments of this application propose a single-cell battery, the single-cell battery having a first orientation, the single-cell battery comprising: A housing having an opening; The top cover assembly includes a cover plate assembly and an electrode assembly. The cover plate assembly includes a cover plate, a plastic part, and a first separator. The cover plate is connected to the housing and covers the opening. The cover plate has a mounting hole, through which at least a portion of the electrode assembly passes. The electrode assembly is connected to the electrode ear, which is located inside the housing. The cover plate has an inner surface facing the interior of the housing. The plastic part is disposed on the inner surface, and the first separator is located between the plastic part and the inner surface. Along the first direction, the first projection of the electrode ear on the inner surface and the second projection of the first separator on the inner surface at least partially overlap.

[0005] Optionally, the electrode assembly includes an electrode body and an electrode plate. Along the first direction, the electrode plate has a first surface facing the cover plate and a second surface away from the cover plate. The electrode body is connected to the first surface, and at least a portion of the electrode body passes through the mounting hole, and at least a portion of the electrode tab is connected to the second surface. Along the first direction, the first projection of the electrode tab on the inner surface includes a first partial projection and a second partial projection. The first partial projection coincides with the projection of the pole plate on the inner surface, and the second partial projection at least partially coincides with the second projection of the first isolator on the inner surface.

[0006] Optionally, the area of ​​the second projection of the first spacer on the inner surface is S1 mm. 2 The area of ​​the second projected portion is S² mm. 2 The following condition is met: S1≥S2.

[0007] Optionally, the single cell further includes a second separator, the second separator being located between the first surface and the plastic part, and the electrode body passing through the second separator; The pole plate also has a first side surface, which is located between the first surface and the second surface. The first side surface is connected to the first surface and the second surface respectively, and the first side surface is inclined relative to the first surface and the second surface. Along the first direction, the projection of the first surface onto the inner surface lies inside the projection of the second surface onto the inner surface, and the projection of the first side onto the inner surface at least partially overlaps with the projection of the second spacer onto the inner surface.

[0008] Optionally, the first side surface and the first surface are connected by a rounded transition.

[0009] Optionally, the single battery cell further includes a third separator located between the first surface and the plastic part, and the electrode body passes through the third separator; The pole plate also has a second side surface located between the first surface and the second surface. The second side surface is connected to the first surface and the second surface respectively. The surface of the third separator facing the first surface is provided with a groove. The pole plate is at least partially embedded in the groove along the first direction, and at least part of the second side surface is located in the groove.

[0010] Optionally, the second side is perpendicular to both the first surface and the second surface, and the groove walls along the direction from the interior of the housing to the cover plate are parallel to the second side.

[0011] Optionally, the third isolation member includes an isolation base plate and an isolation side plate. The isolation side plate is disposed on the surface of the isolation base plate facing the pole plate and extends along the circumferential direction of the isolation base plate. The isolation side plate and the isolation base plate enclose the groove, at least a portion of the pole plate is located in the groove, and at least a portion of the second side of the pole plate faces the isolation base plate.

[0012] Optionally, along the first direction, the first spacer has opposing first and second surfaces, at least one of the first and second surfaces being provided with adhesive, the adhesive being bonded to at least one of the cover plate and the plastic part.

[0013] Secondly, embodiments of this application provide a battery pack, characterized in that it includes any one of the single-cell batteries described in the first aspect above.

[0014] In this embodiment, since the housing has an opening, the top cover assembly includes a cover plate assembly and an electrode assembly. The cover plate assembly includes a cover plate, a plastic part, and a first separator. The cover plate is connected to the housing and covers the opening. Therefore, the cover plate can seal the opening, thereby enclosing a relatively closed space with the housing and protecting the components within the space. Additionally, the cover plate has mounting holes, allowing the electrode assembly to be installed in these holes, with at least a portion of the electrode assembly passing through the holes. Furthermore, the electrode assembly is connected to tabs located inside the housing. These tabs connect to the cell assembly of a single battery cell, allowing the electrical energy of the cell assembly to be transferred to the electrode assembly via the tabs, and then further transferred outwards via the electrode assembly. Furthermore, since the cover plate has an inner surface facing the interior of the housing, the plastic part is disposed on the inner surface, and the first separator is located between the plastic part and the inner surface, along the first direction, the first projection of the tab on the inner surface and the second projection of the first separator on the inner surface at least partially overlap. Therefore, when a single cell experiences thermal runaway, even if the tab contacts the plastic part on the cover plate along the first direction, causing the plastic part to melt (i.e., the heat from the tab melts through the plastic part), the presence of the first separator prevents the tab from contacting the cover plate after melting through the plastic part. The first separator effectively prevents the tab from contacting the cover plate, thus avoiding a potential short circuit in the single cell and improving the safety of the single cell. In other words, in this embodiment, by providing a first separator between the plastic part and the cover plate, the problem of the tab contacting the plastic part along the first direction and melting through it to contact the cover plate can be effectively prevented when a single cell experiences thermal runaway. This effectively reduces the probability of a short circuit during thermal runaway of the single cell and thus effectively improves the safety of the single cell. Attached Figure Description

[0015] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 This diagram shows an exploded view of a single-cell battery provided in an embodiment of this application. Figure 2 This is a cross-sectional view of a single battery cell provided in an embodiment of this application; Figure 3 express Figure 2A magnified view of a section at point A in the middle; Figure 4 This represents one of the exploded views of a top cover assembly provided in an embodiment of this application; Figure 5 This diagram illustrates a pole post assembly provided in an embodiment of this application. Figure 6 A schematic diagram illustrating the positional relationship between a pole post assembly and a second isolator provided in an embodiment of this application; Figure 7 This diagram illustrates a top cover assembly provided in an embodiment of this application. Figure 8 A schematic diagram illustrating the positional relationship between a pole assembly and a third isolation chamber provided in an embodiment of this application; Figure 9 This is a second exploded view of a top cover assembly provided in an embodiment of this application; Figure 10 This is a partial schematic diagram of a single-cell battery provided in an embodiment of this application; Figure 11 This is a schematic diagram showing the projection of a tab and a first spacer onto the inner surface of a cover plate, as provided in an embodiment of this application.

[0016] Figure label: 001: First projection; 002: Second projection; 10: Housing; 101: Opening; 20: Top cover assembly; 21: Cover plate assembly; 22: Terminal post assembly; 211: Cover plate; 212: Plastic part; 213: First separator; 2111: Inner surface; 221: Terminal post body; 222: Terminal post plate; 2221: First surface; 2222: Second surface; 2223: First side; 2224: Second side; 30: Tab; 40: Second separator; 50: Third separator; 501: Groove; 60: Cell assembly; 70: Bottom cover assembly; X: First direction. Detailed Implementation

[0017] The embodiments of this application will now be described in detail. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0018] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise stated, "multiple" means two or more. Furthermore, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0019] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0020] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0021] This application provides a single-cell battery, such as... Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 11As shown, the single battery cell has a first direction X. The single battery cell includes: a housing 10 with an opening 101; a top cover assembly 20, which includes a cover plate assembly 21 and an electrode assembly 22. The cover plate assembly 21 includes a cover plate 211, a plastic part 212, and a first separator 213. The cover plate 211 is connected to the housing 10 and covers the opening 101. The cover plate 211 is provided with a mounting hole, and at least a portion of the electrode assembly 22 passes through the mounting hole. The electrode assembly 22 is connected with an electrode tab 30, which is located inside the housing 10. The cover plate 211 has an inner surface 2111 facing the inside of the housing 10. The plastic part 212 is disposed on the inner surface 2111, and the first separator 213 is located between the plastic part 212 and the inner surface 2111. Along the first direction X, the first projection 001 of the electrode tab 30 on the inner surface 2111 and the second projection 002 of the first separator 213 on the inner surface 2111 at least partially overlap.

[0022] In this embodiment, since the housing 10 has an opening 101, the top cover assembly 20 includes a cover plate assembly 21 and an electrode assembly 22. The cover plate assembly 21 includes a cover plate 211, a plastic part 212, and a first separator 213. The cover plate 211 is connected to the housing 10 and covers the opening 101. Therefore, the cover plate 211 can block the opening 101, thereby forming a relatively closed space with the housing 10, and protecting the components within the space. In addition, the cover plate 211 is provided with a mounting hole, so that the electrode assembly 22 can be installed in the mounting hole, and at least a portion of the electrode assembly 22 passes through the mounting hole. In addition, the electrode assembly 22 is connected to a tab 30, which is located inside the housing 10. The tab 30 can be connected to the cell assembly 60 of the single battery cell, so that the electrical energy of the cell assembly 60 is transferred to the electrode assembly 22 through the tab 30, and then transferred outward through the electrode assembly 22. Furthermore, since the cover plate 211 has an inner surface 2111 facing the interior of the housing 10, the plastic part 212 is disposed on the inner surface 2111, and the first separator 213 is located between the plastic part 212 and the inner surface 2111, along the first direction X, the first projection 001 of the tab 30 on the inner surface 2111 and the second projection 002 of the first separator 213 on the inner surface 2111 at least partially overlap. Therefore, when a single cell experiences thermal runaway, even if the tab 30 contacts the plastic part 212 on the cover plate 211 along the first direction X, causing the plastic part 212 to melt, i.e., the heat of the tab 30 melts through the plastic part 212, the presence of the first separator 213 prevents the tab 30 from contacting the cover plate 211 after melting through the plastic part 212, thus preventing the single cell from short-circuiting and improving the safety of the single cell. That is, in this embodiment of the application, by providing a first separator 213 between the plastic part 212 and the cover plate 211, the problem of the tab 30 contacting the plastic part 212 along the first direction X and melting through the plastic part 212 to contact the cover plate 211 can be effectively avoided when the single cell experiences thermal runaway. This can effectively reduce the probability of short circuit when the single cell experiences thermal runaway, thereby effectively improving the safety of the single cell.

[0023] It should be noted that in this embodiment, the first insulating member 213 is a high-temperature resistant insulating member, meaning that the first insulating member 213 can withstand high temperatures, preventing the first insulating member 213 from being melted through by the heat of the electrode 30 after it comes into contact with the cover plate 211. Specifically, the first insulating member 213 can be formed of a high-temperature resistant material, for example, the first insulating member 213 can be formed of ceramic, or for example, the first insulating member 213 can be formed of mica. The specific material of the first insulating member 213 is not limited in this embodiment. Furthermore, in this embodiment, to facilitate the installation of the first insulating member 213, the first insulating member 213 can be a high-temperature resistant insulating tape, allowing it to be directly attached to the cover plate 211.

[0024] Additionally, in the embodiments of this application, such as Figure 1 As shown, the single battery cell also includes a bottom cover assembly 70 and a cell assembly 60. The housing 10 has a bottom opening opposite to the opening 101. The bottom cover assembly 70 includes a bottom cover plate that closes to the bottom opening. The cell assembly 60 is located inside the housing 10. The top cover assembly 20, the housing 10, and the bottom cover assembly 70 can enclose and form a closed space to protect the cell assembly 60. One end of the tab 30 is connected to the cell assembly 60, and the other end of the tab 30 is connected to the terminal assembly 22, allowing the electrical energy of the cell assembly 60 to be transferred to the terminal assembly 22.

[0025] Additionally, in this embodiment, the cover plate assembly may further include a pressure relief valve disposed on the cover plate. Furthermore, the bottom cover assembly may also include a pressure relief valve disposed on the bottom cover plate.

[0026] In addition, in this embodiment of the application, the electrode assembly 22 includes a positive electrode assembly 22 and a negative electrode assembly 22, both of which are mounted on the cover plate 211.

[0027] Additionally, in some embodiments, such as Figure 3 and Figure 4 As shown, the pole assembly 22 includes a pole body 221 and a pole plate 222. Along the first direction X, the pole plate 222 has a first surface 2221 facing the cover plate 211 and a second surface 2222 away from the cover plate 211. The pole body 221 is connected to the first surface 2221, and at least a portion of the pole body 221 passes through the mounting hole. At least a portion of the tab 30 is connected to the second surface 2222. Along the first direction X, the first projection of the tab 30 on the inner surface 2111 includes a first partial projection and a second partial projection. The first partial projection coincides with the projection portion of the pole plate 222 on the inner surface 2111, and the second partial projection at least partially coincides with the second projection of the first isolator 213 on the inner surface 2111.

[0028] Since the terminal plate 222 has a first surface 2221 facing the cover plate 211 and a second surface 2222 away from the cover plate 211, the terminal body 221 is connected to the first surface 2221, and at least a portion of the terminal body 221 passes through the mounting hole, and at least a portion of the tab 30 is connected to the second surface 2222, once the tab 30 is connected to the cell assembly 60 of the single battery cell, the tab 30 can transfer the electrical energy of the cell assembly 60 to the second surface 2222 of the terminal plate 222, that is, transfer the electrical energy to the terminal plate 222, and the terminal plate 222 transfers the electrical energy to the terminal body 221, so that the terminal body 221 can transfer electrical energy outward. In addition, the first part of the projection coincides with the projection of the electrode plate 222 on the inner surface 2111, and the second part of the projection coincides with the projection of the first separator 213 on the inner surface 2111. Therefore, it is equivalent to only a part of the tab 30 being outside the range of the electrode plate 222, and this part of the tab 30 is directly opposite the first separator 213 in the first direction X. Thus, in the event of thermal runaway of a single cell, even if this part of the tab 30 contacts the plastic part 212 along the first direction X and melts through the plastic part 212, this part of the tab 30 will still contact the first separator 213, thereby being isolated by the first separator 213 to avoid contact with the cover plate 211, which can effectively prevent the problem of short circuit in the single cell. By setting the first part of the projection to coincide with the projection of the electrode plate 222 on the inner surface 2111, and the second part of the projection to coincide with the projection of the first separator 213 on the inner surface 2111, the problem of short circuit in the single cell caused by the contact between the tab 30 and the cover plate 211 during thermal runaway of the single cell can be effectively avoided, thereby effectively improving the safety of the single cell.

[0029] In addition, in some embodiments, the area of ​​the second projection of the first spacer 213 on the inner surface 2111 is S1mm. 2 The area of ​​the second projected part is S² mm. 2 The condition is satisfied that S1 ≥ S2. This configuration effectively makes the first separator 213 larger. Therefore, even if the tab 30 melts through the plastic part 212 after thermal runaway of the individual battery and contact with it along the first direction X, the larger size of the first separator 213 ensures that the tab 30 contacts the first separator 213 as closely as possible, preventing it from contacting the cover plate 211 and thus avoiding a potential short circuit in the individual battery. In other words, by setting S1 ≥ S2, the safety of the individual battery can be effectively improved.

[0030] In some embodiments, the second portion of the projection is located inside the projection of the first separator 213 on the inner surface 2111. With this arrangement, even if the tab 30 melts through the plastic component 212 in the event of thermal runaway of a single battery cell, the second portion of the projection being inside the projection of the first separator 213 on the inner surface 2111 effectively ensures that the tab 30, after melting through the plastic component 212, will not contact the cover plate 211, thus effectively preventing a potential short circuit in the single battery cell. In other words, by setting the second portion of the projection to be inside the projection of the first separator 213 on the inner surface 2111, the safety of the single battery cell can be effectively improved.

[0031] Additionally, in some embodiments, such as Figure 4 , Figure 5 and Figure 6 As shown, the single cell also includes a second separator 40, which is located between the first surface 2221 and the plastic part 212, and the electrode body 221 passes through the second separator 40; the electrode plate 222 also has a first side 2223, which is located between the first surface 2221 and the second surface 2222, and the first side 2223 is connected to the first surface 2221 and the second surface 2222 respectively, and the first side 2223 is inclined relative to the first surface 2221 and the second surface 2222; along the direction from the inside of the housing 10 to the cover plate 211, the projection of the first surface 2221 on the inner surface 2111 is located inside the projection of the second surface 2222 on the inner surface 2111, and the projection of the first side 2223 on the inner surface 2111 at least partially overlaps with the projection of the second separator 40 on the inner surface 2111.

[0032] Since the pole plate 222 also has a first side surface 2223, which is located between the first surface 2221 and the second surface 2222, and the first side surface 2223 is connected to the first surface 2221 and the second surface 2222 respectively, and the first side surface 2223 is inclined relative to the first surface 2221 and the first side surface 2223 is inclined relative to the second surface 2222, along the direction from the inside of the housing 10 to the cover plate 211, the projection of the first surface 2221 on the inner surface 2111 is located inside the projection of the second surface 2222 on the inner surface 2111. Therefore, it is equivalent to the pole plate 222 having a chamfered structure, making it difficult for the second surface 2222 of the pole plate 222 to contact the cover plate 211. Furthermore, the second separator 40 is located between the first surface 2221 and the plastic part 212, and the electrode post body 221 passes through the second separator 40. The projection of the first side 2223 on the inner surface 2111 at least partially overlaps with the projection of the second separator 40 on the inner surface 2111. Therefore, the second separator 40 will not affect the installation of the electrode post assembly 22. In the event of thermal runaway of a single battery, even if the electrode post plate 222 moves along the first direction X, causing the electrode post plate 222 to move towards the plastic part 212, the presence of the second separator 40 ensures that the first side 2223 only contacts the second separator 40, effectively preventing the electrode post plate 222 from contacting the cover plate 211, which could lead to a short circuit in the single battery. In other words, by setting the projection of the first side 2223 on the inner surface 2111 to at least partially overlap with the projection of the second separator 40 on the inner surface 2111, the electrode post plate 222 can be effectively prevented from contacting the cover plate 211, thereby effectively improving the safety of the single battery.

[0033] In addition, in this embodiment, the single battery cell may also include a second separator 40, which is located between the cover plate 211 and the plastic part 212, and the electrode body 221 passes through the second separator 40; the electrode plate 222 also has a first side 2223, which is located between the first surface 2221 and the second surface 2222, and the first side 2223 is connected to the first surface 2221 and the second surface 2222 respectively, and the first side 2223 is inclined relative to the first surface 2221 and the first side 2223 is inclined relative to the second surface 2222; along the first direction X, the projection of the first surface 2221 on the inner surface 2111 is located inside the projection of the second surface 2222 on the inner surface 2111, and the projection of the first side 2223 on the inner surface 2111 at least partially overlaps with the projection of the second separator 40 on the inner surface 2111. With this configuration, it is equivalent to setting a second separator 40 between the cover plate 211 and the plastic part 212. Thus, in the event of thermal runaway of a single cell, even if the electrode plate 222 moves along the first direction X and comes into contact with the plastic part 212, even if the electrode plate 222 melts through the plastic part 212, the electrode plate 222 will only contact the second separator 40. This effectively avoids the electrode plate 222 from contacting the cover plate 211, which could lead to a short circuit in the single cell.

[0034] In some embodiments, the projection of the first side 2223 onto the inner surface 2111 is located inside the projection of the second separator 40 onto the inner surface 2111. With this arrangement, even if the first side 2223 of the electrode plate 222 moves during thermal runaway of a single cell, the first side 2223 will only contact the second separator 40. This effectively ensures that the first side 2223 only contacts the second separator 40, effectively preventing the first side 2223 from contacting the cover plate 211 and thus avoiding a potential short circuit in the single cell.

[0035] In addition, in some embodiments, the connection between the first side surface 2223 and the first surface 2221 is rounded. This design effectively avoids stress concentration at the connection between the first side surface 2223 and the first surface 2221, preventing excessive stress on the pole plate 222 at that location. It also prevents scratches on the plastic part 212 at the connection, thus avoiding potential damage to the plastic part 212. In other words, by providing a rounded transition at the connection between the first side surface 2223 and the first surface 2221, the plastic part 212 can be protected.

[0036] Additionally, in some embodiments, such as Figure 7 , Figure 8 , Figure 9 and Figure 10As shown, the single cell also includes a third separator 50, which is located between the first surface 2221 and the plastic part 212, and the electrode plate 221 passes through the third separator 50; the electrode plate 222 also has a second side 2224, which is located between the first surface 2221 and the second surface 2222, and the second side 2224 is connected to the first surface 2221 and the second surface 2222 respectively. The surface of the third separator 50 facing the first surface 2221 is provided with a groove 501, and the electrode plate 222 is at least partially embedded in the groove 501 along the first direction X, and at least part of the second side 2224 is located in the groove 501.

[0037] Since the pole plate 222 also has a second side surface 2224, which is located between the first surface 2221 and the second surface 2222, and is connected to both the first surface 2221 and the second surface 2222, and the third separator 50 is located between the first surface 2221 and the plastic part 212, the surface of the third separator 50 facing the first surface 2221 is provided with a groove 501, and the pole plate 222 is at least partially embedded in the groove 501 along the first direction X, and at least part of the second side surface 2224 is located in the groove 501. Therefore, the electrode plate 222 and the cover plate 211 are effectively isolated by the third separator 50. Even if the single cell experiences thermal runaway and the electrode plate 222 moves along the first direction X, the electrode plate 222 is at least partially embedded in the groove 501 along the first direction X, and at least part of the second side 2224 is located in the groove 501. This effectively ensures that the electrode plate 222 remains in contact with the third separator 50 during movement and is isolated by the third separator 50, effectively preventing the electrode plate 222 from contacting the cover plate 211 and causing the single cell to potentially experience thermal runaway. In other words, by setting the third separator 50, the safety of the single cell can be effectively improved.

[0038] It should be noted that the second side 2224 can be perpendicular to the first surface 2221 and the second surface 2222.

[0039] In some embodiments, the second side 2224 is entirely located within the groove 501 along the first direction X. This arrangement effectively ensures that the electrode plate 222 will not contact the cover plate 211 in the event of thermal runaway of a single battery cell, thereby effectively preventing potential short circuits in the single battery cell. In other words, by ensuring that the second side 2224 is entirely located within the groove 501 along the first direction X, the safety of the single battery cell can be effectively improved, further enhancing its safety.

[0040] In some embodiments, the second side surface 2224 is perpendicular to both the first surface 2221 and the second surface 2222, and the groove wall of the groove 501 along the direction from the interior of the housing 10 to the cover plate 211 is parallel to the second side surface 2224. With this arrangement, when the electrode plate 222 is embedded in the groove 501, the groove wall of the groove 501 can effectively protect the second side surface 2224 of the electrode plate 222 and also protect the first surface 2221 of the electrode plate 222, effectively preventing the electrode plate 222 from contacting the cover plate 211 and thus avoiding potential thermal runaway of the individual battery.

[0041] Additionally, in some embodiments, such as Figure 8 As shown, the third separator 50 includes a bottom separator 51 and a side separator 52. The side separator 52 is disposed on the surface of the bottom separator 51 facing the electrode plate 222, and extends along the circumferential direction of the bottom separator 51. The side separator 52 and the bottom separator 51 enclose a groove 501, in which at least a portion of the electrode plate 222 is located, and at least a portion of the second side surface 2224 of the electrode plate 222 faces the bottom separator 51. With this arrangement, the bottom separator 51 and the side separator 52 enclose the groove 501, so that after the electrode plate 222 is located in the groove 501, the electrode plate 222 can be effectively isolated by the bottom separator 51 and the side separator 52, effectively preventing the electrode plate 222 from contacting the cover plate 211, which could lead to thermal runaway of the single cell.

[0042] It should be noted that, in the embodiments of this application, the isolation base plate 51 and the isolation side plate 52 can be integrally formed.

[0043] In some embodiments, the thickness of the first separator 213 is L mm, satisfying: 0.2 ≤ L ≤ 1.5. This arrangement minimizes the impact of the first separator 213 on the thickness of the cover assembly 21, ensuring improved safety for the individual battery cells while minimizing the increase in volume due to the presence of the first separator 213.

[0044] It should be noted that the thickness L of the first spacer 213 can be any value from 0.2 mm to 1.5 mm. For example, the thickness L of the first spacer 213 is 0.2 mm, 0.5 mm, 1 mm, or 1.5 mm. The specific value of the thickness of the first spacer 213 is not limited in this embodiment.

[0045] In addition, in this embodiment, the thickness of the second spacer 40 can also be Lmm, and the thickness of the third spacer 50 can also be Lmm. Furthermore, the thicknesses of the first spacer 213, the second spacer 40, and the third spacer 50 can be equal; of course, the thicknesses of the first spacer 213, the second spacer 40, and the third spacer 50 can also be unequal; and, alternatively, two of the thicknesses of the first spacer 213, the second spacer 40, and the third spacer 50 can be equal. This embodiment does not limit the specific application of this method.

[0046] In addition, in the embodiments of this application, the materials of the first isolation member 213, the second isolation member 40, and the third isolation member 50 can be the same. That is, the second isolation member 40 and the third isolation member 50 can both be formed of a high-temperature resistant and insulating material. For example, the second isolation member 40 and the third isolation member 50 can both be formed of ceramic, or, for another example, the second isolation member 40 and the third isolation member 50 can both be formed of mica.

[0047] In some embodiments, along the first direction X, the first spacer 213 has opposing first and second surfaces, and at least one of the first and second surfaces is provided with adhesive, which is then bonded to at least one of the cover plate 211 and the plastic part 212. This arrangement allows the first spacer 213 to be directly bonded to the cover plate 211 and / or the plastic part 212, thereby facilitating the installation of the first spacer 213.

[0048] It should be noted that in this embodiment, adhesive can be provided only on the first surface, or only on the second surface; alternatively, adhesive can be provided on both the first and second surfaces. Specifically, when adhesive is provided only on the first surface, the first surface can be bonded to the cover plate 211; when adhesive is provided only on the second surface, the second surface can be bonded to the cover plate 211; and when adhesive is provided on both the first and second surfaces, the first surface can be bonded to the cover plate 211, and the second surface can be bonded to the plastic part 212.

[0049] In this embodiment, since the housing 10 has an opening 101, the top cover assembly 20 includes a cover plate assembly 21 and an electrode assembly 22. The cover plate assembly 21 includes a cover plate 211, a plastic part 212, and a first separator 213. The cover plate 211 is connected to the housing 10 and covers the opening 101. Therefore, the cover plate 211 can block the opening 101, thereby forming a relatively closed space with the housing 10, and protecting the components within the space. In addition, the cover plate 211 is provided with a mounting hole, so that the electrode assembly 22 can be installed in the mounting hole, and at least a portion of the electrode assembly 22 passes through the mounting hole. In addition, the electrode assembly 22 is connected to a tab 30, which is located inside the housing 10. The tab 30 can be connected to the cell assembly 60 of the single battery cell, so that the electrical energy of the cell assembly 60 is transferred to the electrode assembly 22 through the tab 30, and then transferred outward through the electrode assembly 22. Furthermore, since the cover plate 211 has an inner surface 2111 facing the interior of the housing 10, the plastic part 212 is disposed on the inner surface 2111, and the first separator 213 is located between the plastic part 212 and the inner surface 2111, along the first direction X, the first projection 001 of the tab 30 on the inner surface 2111 and the second projection 002 of the first separator 213 on the inner surface 2111 at least partially overlap. Therefore, when a single cell experiences thermal runaway, even if the tab 30 contacts the plastic part 212 on the cover plate 211 along the first direction X, causing the plastic part 212 to melt, i.e., the heat of the tab 30 melts through the plastic part 212, the presence of the first separator 213 prevents the tab 30 from contacting the cover plate 211 after melting through the plastic part 212, thus preventing the single cell from short-circuiting and improving the safety of the single cell. That is, in this embodiment of the application, by providing a first separator 213 between the plastic part 212 and the cover plate 211, the problem of the tab 30 contacting the plastic part 212 along the first direction X and melting through the plastic part 212 to contact the cover plate 211 can be effectively avoided when the single cell experiences thermal runaway. This can effectively reduce the probability of short circuit when the single cell experiences thermal runaway, thereby effectively improving the safety of the single cell.

[0050] This application provides a battery pack, including any of the individual batteries described in the above embodiments.

[0051] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0052] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A single-cell battery, characterized in that, The single cell has a first orientation, and the single cell includes: A housing having an opening; The top cover assembly includes a cover plate assembly and an electrode assembly. The cover plate assembly includes a cover plate, a plastic part, and a first separator. The cover plate is connected to the housing and covers the opening. The cover plate has a mounting hole, through which at least a portion of the electrode assembly passes. The electrode assembly is connected to the electrode ear, which is located inside the housing. The cover plate has an inner surface facing the interior of the housing. The plastic part is disposed on the inner surface, and the first separator is located between the plastic part and the inner surface. Along the first direction, the first projection of the electrode ear on the inner surface and the second projection of the first separator on the inner surface at least partially overlap.

2. The single-cell battery according to claim 1, characterized in that, The electrode assembly includes an electrode body and an electrode plate. Along the first direction, the electrode plate has a first surface facing the cover plate and a second surface away from the cover plate. The electrode body is connected to the first surface, and at least a portion of the electrode body passes through the mounting hole. At least a portion of the electrode tab is connected to the second surface. Along the first direction, the first projection of the electrode tab on the inner surface includes a first partial projection and a second partial projection. The first partial projection coincides with the projection of the pole plate on the inner surface, and the second partial projection at least partially coincides with the second projection of the first isolator on the inner surface.

3. The single-cell battery according to claim 2, characterized in that, The area of ​​the second projection of the first spacer on the inner surface is S1mm. 2 The area of ​​the second projected portion is S² mm. 2 The following condition is met: S1≥S2.

4. The single-cell battery according to claim 2, characterized in that, The single battery cell also includes a second separator, which is located between the first surface and the plastic part, and the electrode body passes through the second separator; The pole plate also has a first side surface, which is located between the first surface and the second surface. The first side surface is connected to the first surface and the second surface respectively, and the first side surface is inclined relative to the first surface and the second surface. Along the first direction, the projection of the first surface onto the inner surface lies inside the projection of the second surface onto the inner surface, and the projection of the first side onto the inner surface at least partially overlaps with the projection of the second spacer onto the inner surface.

5. The single-cell battery according to claim 4, characterized in that, The first side surface and the first surface are connected by a rounded transition.

6. The single-cell battery according to claim 2, characterized in that, The single battery cell also includes a third separator, which is located between the first surface and the plastic part, and the electrode body passes through the third separator; The pole plate also has a second side surface located between the first surface and the second surface. The second side surface is connected to the first surface and the second surface respectively. The surface of the third separator facing the first surface is provided with a groove. The pole plate is at least partially embedded in the groove along the first direction, and at least part of the second side surface is located in the groove.

7. The single-cell battery according to claim 6, characterized in that, The second side is perpendicular to both the first surface and the second surface, and the groove wall along the direction from the interior of the housing to the cover plate is parallel to the second side.

8. The single-cell battery according to claim 6, characterized in that, The third isolation element includes an isolation base plate and an isolation side plate. The isolation side plate is disposed on the surface of the isolation base plate facing the pole plate and extends along the circumferential direction of the isolation base plate. The isolation side plate and the isolation base plate enclose the groove, at least a portion of the pole plate is located in the groove, and at least a portion of the second side of the pole plate faces the isolation base plate.

9. The single-cell battery according to any one of claims 1-8, characterized in that, Along the first direction, the first spacer has opposing first and second surfaces, at least one of the first and second surfaces being provided with adhesive, the adhesive being bonded to at least one of the cover plate and the plastic part.

10. A battery pack, characterized in that, The single-cell battery includes any one of claims 1-9.

Images