Battery cells, batteries and electrical devices

Abstract

The present invention relates to a battery cell, a battery, and an electric device, which belong to the technical field of batteries. The battery cell includes a case assembly that defines a storage cavity and has a flow path that communicates with the storage cavity, and a sealing structure that is fitted to the case assembly and configured to open or close the flow path.

Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application is based on and claims priority from a Chinese patent application with application number 202311071807.X and filing date August 23, 2023, the entire contents of which are hereby incorporated by reference into this application.

[0002] This application relates to the technical field of batteries, and in particular to battery cells, batteries and electrical devices. [Background technology]

[0003] In recent years, new energy vehicles have developed dramatically, and in the field of electric vehicles, power batteries play an irreplaceable and important role as the power source of electric vehicles. Among them, power batteries contain several battery cells, and there is room for improving the reliability and service life of battery cells. Summary of the Invention

[0004] The embodiments of the present application provide battery cells, batteries, and electrical devices that are useful for improving the reliability and service life of battery cells.

[0005] In a first aspect, an embodiment of the present application provides a battery cell including a case assembly defining a storage cavity and having a flow path communicating with the storage cavity, and a sealing structure fitted to the case assembly and configured to open or seal the flow path.

[0006] In the above technical solution, the battery cell is provided with a sealing structure capable of opening and closing a flow path, which opens the flow path during the production stage of the battery cell. At this time, electrolyte is injected into the accommodating cavity through the flow path. After the electrolyte is injected, the sealing structure closes and seals the flow path, preventing electrolyte overflow and allowing the battery cell to be used normally. During use of the battery cell, as the electrolyte is consumed, the amount of electrolyte in the case assembly decreases, affecting the service life of the battery cell. Therefore, by periodically opening the flow path in the sealing structure, electrolyte can be added and replenished through the flow path to extend the service life of the battery cell. During use of the battery cell, the electrolyte generates gas after participating in a reaction, which increases the pressure in the case assembly. When the pressure reaches a certain level, reliability issues arise. Therefore, by periodically opening the flow path in the sealing structure during use of the battery cell, pressure in the accommodating cavity can be periodically released through the flow path, improving the service reliability of the battery cell. In summary, the battery cell according to the embodiment of the present application can improve the service life and reliability of the battery cell while meeting manufacturing requirements.

[0007] In some embodiments, the sealing structure is removably mated to the case assembly.

[0008] In the above technical solution, by disposing the sealing structure detachably relative to the case assembly, compared to a solution in which the sealing structure is movable relative to the case assembly to open and close the flow path, the method of connecting the sealing structure to the case assembly is simplified, the design and processing of the case assembly are simplified, and the reliability of sealing of the sealing structure to the case assembly is improved. Furthermore, compared to a solution in which the sealing structure is switched between different forms to open and close the flow path, the structural complexity of the sealing structure itself is reduced, and the processing difficulty of the sealing structure is reduced, which is helpful in reducing the processing cost.

[0009] In some embodiments, the sealing structure comprises a first structural member and a second structural member, the second structural member sealingly engaged with the flow passage, the first structural member lockingly engaged with the case assembly to restrict the second structural member in a position that seals the flow passage, and located on a side of the second structural member away from the receiving cavity.

[0010] In the above technical solution, the second structural member in the sealing structure can seal the flow path, and the first structural member can limit the position of the second structural member, preventing the second structural member from escaping away from the accommodating cavity and ensuring that the second structural member always seals the flow path, thereby improving the sealing effect of the second structural member. Furthermore, because the sealing structure is composed of the first structural member and the second structural member, the design of the first structural member can be focused primarily on the convenience and reliability of the locking, without considering sealing or excessively considering it, thereby improving the reliability and convenience of the locking of the first structural member. Meanwhile, the design of the second structural member can be focused primarily on the sealing of the flow path, without considering locking or excessively considering it, thereby improving the reliability of the sealing of the flow path by the second structural member. Furthermore, since there are relatively few factors to consider when designing the first structural member and the second structural member, respectively, this helps to design the first structural member and the second structural member relatively easily, and makes it convenient to process the first structural member and the second structural member.

[0011] In some embodiments, the first structural member and the second structural member are connected.

[0012] In the above technical solution, when installing, the first structural member is first assembled and connected to the second structural member to form an assembly, and then the assembly consisting of the first structural member and the second structural member can be installed toward the flow path of the case assembly, thereby improving the efficiency of installing the sealing structure to the case assembly. Furthermore, since the first structural member and the second structural member are connected, the positional restriction effect of the first structural member on the second structural member is ensured, and the first structural member can more stably position the second structural member in a position to seal the flow path.

[0013] In some embodiments, the first structural member and the second structural member are removably connected.

[0014] In the above technical solution, the first structural member and the second structural member are removably connected, so that if one of the first structural member and the second structural member is damaged, the first structural member or the second structural member can be removed and replaced, thereby reducing the maintenance costs of the sealing structure.

[0015] In some embodiments, the connection between the first structural member and the second structural member is such that the first structural member and the second structural member remain connected when the sealing structure is removed from the case assembly.

[0016] In the above technical solution, when the first structural member is removed from the case assembly, the second structural member and the first structural member remain connected, so that the second structural member can be detached from the case assembly together with the first structural member, thereby improving the efficiency of removing the sealing structure from the case assembly and facilitating maintenance work.

[0017] In some embodiments, the first structural member has a first mating portion on a side facing the second structural member, and the second structural member has a second mating portion on a side facing the first structural member, wherein one of the first mating portion and the second mating portion is a convex structure and the other is a concave structure, and the convex structure is fitted into the concave structure.

[0018] In the above technical solution, the first structural member and the second structural member can be quickly assembled by concave-convex insertion, which makes the design and processing of both members convenient and reduces the processing costs of both members.

[0019] In some embodiments, to prevent the protruding structure from escaping from the concave structure, the protruding structure and the concave structure are fitted together by an interference fit, a screw fit, or a position restriction structure.

[0020] In the above technical solution, when installing, the first structural member and the second structural member can be mounted together in the case assembly, and when removing, the second structural member is detached from the case assembly together with the first structural member, thereby improving the assembly and removal efficiency of the entire sealing structure.

[0021] In some embodiments, at least a portion of the first structural member is fitted within the case assembly.

[0022] The above technical solution improves the tightness of the fit between the sealing structure and the case assembly and helps reduce the space outside the case assembly occupied by the first structural member. If the first structural member is completely fitted into the case assembly and does not protrude from the surface of the case assembly, the possibility of damage to or erroneous unlocking of the first structural member can be reduced, and the reliability of sealing the flow path can be increased.

[0023] In some embodiments, the first structural member is configured to be lockable and unlockable with the case assembly via a rotational movement.

[0024] In the above technical solution, the locking and unlocking method of the first structural member is simple and easy to operate.

[0025] In some embodiments, a tool engagement hole is provided in a surface of the first structural member facing away from the second structural member.

[0026] In the above technical solution, by providing a tool fitting hole on the surface of the first structural member away from the second structural member, it is convenient to rotate the first structural member using a tool to lock and unlock the first structural member. Also, in order to rotate the first structural member, it is not necessary for at least a portion of the first structural member to protrude from the surface of the case assembly. The rotation of the first structural member can also be achieved when at least a portion of the first structural member is fitted into the case assembly.

[0027] In some embodiments, a positioning structure is provided on a surface of the first structural member facing away from the second structural member.

[0028] In the above technical solutions, it is convenient to use the positioning structure to guide the first structural member to the mounting position, thereby quickly aligning the first structural member to the mounting position, and / or to use the positioning structure to detect the rotation angle of the first structural member, thereby reliably rotating the first structural member to a predetermined position and ensuring the reliability of the locking.

[0029] In some embodiments, the first structural member includes a central portion disposed corresponding to the flow path and a locking portion located on an outer peripheral region of the central portion. Alternating stopper portions and escape holes are formed on the case assembly and positioned around the flow path. Receiving grooves are formed on the side of the stopper portions that is close to the accommodating cavity, and the escape holes extend through a surface of the case assembly that is away from the accommodating cavity and communicate with the receiving grooves. The locking portions rotatably enter and exit the receiving grooves through the escape holes.

[0030] In the above technical solution, the first structural member and the case assembly can be locked and unlocked simply by rotating the first structural member without any other excessive operations, thereby reducing the difficulty of the operation and improving the efficiency of removing and assembling the first structural member. Furthermore, the structures of the first structural member and the case assembly are relatively simple, making them easy to process. Furthermore, the locking portions are located around the central portion, so they do not affect the design of the central portion. The size and shape of the central portion can be flexibly designed according to the requirements for fitting with the flow path, improving design flexibility. Furthermore, the locking portions can accommodate the surrounding area of ​​the flow path, so they do not affect the design of the size and shape of the flow path, and the design requirements of the flow path itself can be met.

[0031] In some embodiments, the avoidance holes are multiple and spaced apart around the flow path. A stopper portion is provided between each pair of adjacent avoidance holes. The locking portions are multiple and spaced apart around the central portion. The locking portions are arranged corresponding to the multiple avoidance holes, respectively.

[0032] In the above technical solution, the cooperation of the multiple locking portions and the multiple stopper portions can improve the reliability of the locking engagement between the first structural member and the case assembly. Furthermore, the multiple locking portions are spaced apart, allowing the electrolyte to pass through the spaces between the adjacent locking portions, thereby alleviating the problem of electrolyte accumulation at the locking position and improving the reliability of the battery cell.

[0033] In some embodiments, the case assembly includes a support, and the second structural member includes a lap joint, where the lap joint is lap-jointed to a side of the support away from the receiving cavity and is supported on a side of the first structural member closer to the receiving cavity, or the first structural member is lap-jointed to a side of the support away from the receiving cavity.

[0034] In the above technical solution, the support portion functions to limit the limit of movement of the first structural member toward the receiving cavity, and the stopper portion functions to limit the limit of movement of the first structural member away from the receiving cavity. Therefore, the cooperation of the stopper portion and the support portion allows the first structural member to be stably positioned at the locked position where it is locked into the case assembly, improving the reliability of the locking engagement. Furthermore, the support portion also serves as a positioning function during the assembly process, making it easier for workers to know when the locking portion has reached the position corresponding to the receiving groove. At this time, the first structural member can be rotated and locked, improving the convenience of assembly.

[0035] In some embodiments, a first positioning structure is provided on the side of the stopper portion facing the receiving groove, and a second positioning structure is provided on the side of the locking portion facing the stopper portion, and the positioning engagement between the first positioning structure and the second positioning structure prevents the locking portion from rotating relative to the stopper portion.

[0036] In the above technical solution, by providing a first positioning structure and a second positioning structure, the stability of the locking engagement between the first structural member and the case assembly is improved, and the risk of the first structural member rotating due to an external force and the engaging portion detaching from the stopper portion to release the lock is reduced, thereby increasing the reliability of the locking engagement between the first structural member and the case assembly.

[0037] In some embodiments, one of the first positioning structure and the second positioning structure is a protrusion structure and the other is a groove structure, and the protrusion structure and the groove structure are fitted together.

[0038] In the above technical solution, the positioning and fitting between the first positioning structure and the second positioning structure can be achieved simply and effectively, making the first positioning structure and the second positioning structure easy to process and reducing the manufacturing cost.

[0039] In some embodiments, the protrusion structure includes a plurality of strip ribs spaced apart along the rotational direction of the first structural member, and the groove structure includes a plurality of strip grooves spaced apart along the rotational direction of the first structural member, and the plurality of strip ribs are fitted into the plurality of strip grooves in a one-to-one correspondence.

[0040] In the above technical solution, the reliability and stability of the positioning fitting can be improved, and the stability of the locking fitting between the first structural member and the case assembly can be effectively increased.

[0041] In some embodiments, the protrusion structure includes a bump structure, the groove structure includes an arc-shaped groove extending along the rotation direction of the first structural member, and the bump structure is fitted into the arc-shaped groove.

[0042] In the above technical solution, since the processing precision can be reduced, the positioning and fitting of the protrusion structure and the groove structure can be realized relatively easily.

[0043] In some embodiments, the central portion is fitted into the flow passage to form a cylindrical fit with the flow passage.

[0044] In the above technical solution, when the first structural member rotates, the central portion and the flow path are not affected by interference, ensuring smooth rotation of the first structural member. Furthermore, the fitting gap between the central portion and the flow path can be reduced, reducing the possibility of contaminants entering through the fitting gap, which helps improve the reliability of the battery cell.

[0045] In some embodiments, at least a portion of the second structural member is inserted into the flow passage and has an interference fit with the flow passage so as to seal the flow passage.

[0046] In the above technical solution, the interference fit allows the second structural member to simply and effectively seal the flow path, ensuring good sealing reliability, reducing structural complexity and processing difficulty, and reducing production costs. The interference fit also makes it easy to remove the second structural member and open the flow path.

[0047] In some embodiments, the first structural member forms a cylindrical insert fit with the second structural member, thereby allowing the first structural member to rotate relative to the second structural member.

[0048] In the above technical solution, the first structural member can be rotated relative to the second structural member by inserting and fitting with a cylindrical surface. That is, when the second structural member is tightly fitted into the flow channel, in the process of rotating the first structural member to lock the first structural member, the inserting and fitting with a cylindrical surface allows only the first structural member to rotate without rotating the second structural member together. This reduces the force required to rotate the first structural member and improves the smoothness of rotation of the first structural member.

[0049] In some embodiments, the flow path includes a first passage portion and a second passage portion arranged in sequence along the liquid injection direction, the first passage portion having a cross-sectional area larger than the cross-sectional area of ​​the second passage portion, the second structural member being interference-fitted into the second passage portion, and at least a portion of the first structural member being fitted into the first passage portion.

[0050] In the above technical solution, the provision of a first passage portion having a relatively large cross-sectional area fitted to the first structural member is beneficial to the lock design of the first structural member, making it easier to lock and unlock the first structural member, while the provision of a second passage portion having a relatively small cross-sectional area tightly fitted to the second structural member reduces the difficulty of sealing and improves the sealing effect.

[0051] In some embodiments, the case assembly includes a stepped surface formed at the connection between the first passage portion and the second passage portion, and a portion of the second structural member is partially supported on a side of the stepped surface away from the receiving cavity.

[0052] In the above technical solution, the sealing effect of the second structural member on the flow path is enhanced to some extent, and a part of the second structural member is supported on the side of the step surface away from the accommodating cavity, thereby making it easier to remove the second structural member.

[0053] In some embodiments, the case assembly has a step surface formed at the connection between the first passage portion and the second passage portion, the step surface extending obliquely from the hole wall of the first passage portion in a direction toward the second passage portion, in a direction adjacent to the receiving cavity.

[0054] In the above technical solution, the step surface has a guiding effect of guiding the electrolyte accumulated in the first passage portion to the second passage portion, thereby alleviating the problem of liquid accumulation in the first passage portion and improving the reliability of the battery cell.

[0055] In some embodiments, the sealing structure is configured to be fitted at least partially into the flow channel through an inlet of the flow channel.

[0056] In the above technical solution, this makes it easy to operate the sealing structure to release or seal the flow path. For example, if the sealing structure is removably fitted to the case assembly, the sealing structure can be easily attached and detached. Furthermore, the sealing structure is at least partially fitted into the flow path, i.e., the sealing structure may be completely fitted into the flow path, or only a portion of the sealing structure may be fitted into the flow path. This makes it possible to maximize the use of space within the flow path and increase the reliability of sealing the flow path by the sealing structure, while reducing the height of the sealing structure that protrudes outward from the flow path and reducing the space outside the case assembly occupied by the sealing structure, which helps to reduce the overall size of the battery cell.

[0057] In some embodiments, the case assembly includes a mounting portion, the flow path includes a liquid injection hole formed on the mounting portion, the mounting portion includes a base and a seat attached to the base, and the sealing structure is fitted to the seat and configured to open or seal the liquid injection hole.

[0058] In the above technical solution, the sealing structure is fitted into the base, the base is arranged as a separately processed part, and the base is attached to the base through an assembly process, so that the base can be processed into a shape suitable for fitting with the sealing structure, which simplifies the complexity of the base structure and reduces the difficulty of processing the base, and helps to diversify the types of bases.

[0059] In some embodiments, the case assembly includes a case defining a receiving cavity and a pole structure provided on the case, the pole structure being a mounting portion, the flow path being provided on the mounting portion and including a liquid injection hole, and the sealing structure being fitted to the mounting portion and configured to open or seal the liquid injection hole.

[0060] In the above technical solution, a flow path that can be used for liquid injection is located in the mounting portion, and the electrode structure serves as the mounting portion, allowing electrolyte injection from the electrode structure. This eliminates the need to create a separate flow path on the case, and the flow path does not occupy space in the case. Furthermore, since there is no need to reduce the size of the electrode structure to accommodate the flow path, the area of ​​the electrode structure can be expanded to increase the liquid passage area of ​​the electrode structure without increasing the size of the case, which helps reduce resistance to liquid passage and improve liquid passage efficiency. In addition, increasing the area of ​​the electrode structure also helps with the assembly and connection of the electrode structure to the case. Furthermore, there is no need to increase the size of the case to increase the area of ​​the electrode structure, which helps achieve a smaller and lighter case.

[0061] In some embodiments, the electrode post structure includes a electrode post body attached to the case and a electrode post cover plate covering the electrode post body. The flow path further includes a communication passage formed on the electrode post body and communicating with the receiving cavity. The liquid injection hole is formed on the electrode post cover plate and communicates with the communication passage. The sealing structure is fitted to the electrode post cover plate to open or close the liquid injection hole.

[0062] In the above technical solution, the flow path includes a communication passage and a liquid injection hole, which can extend the liquid injection path to a certain extent and provide a buffering effect against liquid injection to a certain extent, which helps to reduce the possibility of electrolyte splashing or overflowing when the battery cell is injected or operated.

[0063] In some embodiments, the pole cover plate comprises a cover plate portion covered by the pole body and a first base portion attached to the cover plate portion, at least a portion of the liquid injection hole is formed on the first base portion, and the sealing structure is fitted to the first base portion.

[0064] In the above technical solution, a separately processed first base portion is provided, the first base portion is attached to the cover plate portion through an assembly process, and the sealing structure is fitted to the first base portion, thereby processing the first base portion into a shape that is compatible with the sealing structure, reducing the structural complexity of the cover plate portion and facilitating the processing of the cover plate portion.

[0065] In some embodiments, a first mounting groove opening in a direction away from the accommodating cavity is provided on the cover plate portion, and at least a portion of the first base portion is fitted into the first mounting groove.

[0066] The above technical solution helps to improve the assembly efficiency of the cover plate part and the first base part, and the connection stability between the cover plate part and the first base part, and also reduces the space outside the cover plate part occupied by the first base part.

[0067] In some embodiments, the communication passage includes a first accommodating groove that opens toward the pole cover plate and communicates with the liquid injection hole, and a liquid passage hole that penetrates the groove wall of the first accommodating groove and communicates the first accommodating groove with the accommodating cavity.

[0068] In the above technical solution, the communication passage has a first receiving groove formed on the pole body, which can buffer the electrolyte, thereby alleviating problems such as electrolyte splashing or overflowing when the battery cell is filled or operated. Furthermore, the first receiving groove's ability to buffer the electrolyte during filling helps to improve the efficiency of electrolyte filling, and the sidewalls of the first receiving groove can prevent electrolyte splashing to some extent, reducing external contamination caused by the electrolyte.

[0069] In some embodiments, the communicating passage further includes a second accommodating groove located on the side of the first accommodating groove closest to the accommodating cavity, the second accommodating groove opening toward the accommodating cavity and communicating with the accommodating cavity, and the liquid passage hole penetrating the groove wall of the second accommodating groove communicating between the first accommodating groove and the second accommodating groove.

[0070] In the above technical solution, the second accommodating groove can function to buffer the electrolyte or gas. When the electrolyte is injected into the battery cell, the second accommodating groove can be used to buffer the electrolyte, thereby eliminating problems such as electrolyte splashing and overflow. When the battery cell is operating, the electrolyte generates gas after participating in a reaction. The second accommodating groove can be used to buffer the gas generated in the electrolyte or the accommodating cavity, thereby eliminating problems such as electrolyte overflow and excessive gas pressure in the accommodating cavity and improving the reliability of the battery cell.

[0071] In some embodiments, the battery cell comprises a cell assembly including an active material coating portion received in a receiving cavity and a conductive portion connected to the active material coating portion. A through hole is formed on the pole body to connect the first receiving groove and the receiving cavity. There are one or more through holes, and at least one of the through holes is a liquid passage hole. The conductive portion passes through the at least one through hole and is at least partially received in the first receiving groove.

[0072] In the above technical solution, by receiving at least a portion of the conductive part in the first accommodating groove and having at least a portion of the conductive part occupy the space in the first accommodating groove, the space occupied by the conductive part in the accommodating cavity is reduced, and the space in the accommodating cavity can be saved to receive an active material coating part with a larger volume, which is helpful to increase the energy density of the battery cell, or helpful to reduce the size of the battery cell if the energy density of the battery cell remains unchanged.

[0073] In some embodiments, the pole structure includes a pole body attached to the case, the flow path further includes an accommodating groove formed on the pole body together with a liquid injection hole, the liquid injection hole communicates with the accommodating groove by penetrating a groove wall on a side of the accommodating groove away from the groove opening of the accommodating groove, and the sealing structure is fitted to the pole body to open or seal the liquid injection hole.

[0074] In the above technical solution, by arranging the liquid injection hole on the pole body, it is possible to omit the pole cover plate or the liquid injection hole on the pole cover plate, thereby simplifying the structure and processing. Furthermore, since the pole body has a receiving groove communicating with the liquid injection hole, it can meet the liquid injection requirements while providing a relatively large buffer space on the pole body, which can serve to buffer the electrolyte to a certain extent. This helps to reduce the possibility of electrolyte splashing or spilling during the manufacture or use of the battery cell.

[0075] In some embodiments, the pole body comprises a main body portion attached to the case and a second base portion attached to the main body portion, at least a portion of the liquid injection hole is formed on the second base portion, and the sealing structure is fitted to the second base portion.

[0076] In the above technical solution, a separately processed second base portion is provided, the second base portion is attached to the main body portion through an assembly process, and the sealing structure is fitted to the second base portion, thereby processing the second base portion into a shape that is compatible with the sealing structure, reducing the structural complexity of the main body portion and facilitating the processing of the main body portion.

[0077] In some embodiments, the storage groove includes a third storage groove having a groove opening facing away from the storage cavity, and the liquid injection hole penetrates the groove wall of the third storage groove on the side closest to the storage cavity.

[0078] In the above technical solution, the third groove serves to buffer the electrolyte, thereby alleviating problems such as electrolyte splashing and overflow. Furthermore, the sidewall of the third groove can prevent electrolyte splashing to some extent, reducing external contamination of the electrolyte and facilitating rapid injection. Furthermore, the liquid injection nozzle can be flexibly positioned. For example, the outlet of the liquid injection nozzle can be aligned with the groove opening of the third groove, thereby enlarging the outlet, which further improves injection efficiency.

[0079] In some embodiments, the receiving groove further includes a fourth receiving groove having a groove opening facing the receiving cavity. The fourth receiving groove is located on a side of the third receiving groove closer to the receiving cavity. The liquid injection hole penetrates a groove wall on a side of the fourth receiving groove away from the receiving cavity, thereby connecting the third receiving groove and the fourth receiving groove.

[0080] In the above technical solution, the fourth accommodating groove can increase the height of the liquid injection hole when injecting the electrolyte, thereby increasing the total amount of injected electrolyte and helping to extend the cycle life of the battery cell. In addition, when gas generated in the accommodating cavity or electrolyte that is about to overflow may flow into the fourth accommodating groove, the fourth accommodating groove acts as a buffer, improving the reliability of the operation of the battery cell.

[0081] In some embodiments, the storage groove includes a fifth storage groove having a groove opening facing toward the storage cavity, and the liquid injection hole penetrates the groove wall of the fifth storage groove on the side away from the storage cavity.

[0082] In the above technical solution, the fifth groove can buffer the electrolyte, and the sidewall of the fifth groove can prevent the electrolyte from splashing and facilitate rapid injection. Furthermore, the height of the liquid injection hole can be increased. If the liquid injection hole is blocked, gas or electrolyte generated in the accommodating cavity may flow into the fifth groove. Therefore, the fifth groove can act as a buffer, thereby improving the reliability of the battery cell's operation.

[0083] In some embodiments, the case assembly includes a case defining a receiving cavity and a pressure release structure disposed on the case, the pressure release structure and / or a connection between the pressure release structure and the case having a weakened area, the flow path disposed in the pressure release structure and including a liquid inlet hole, and the sealing structure engaged with the pressure release structure and configured to open or seal the liquid inlet hole.

[0084] In the above technical solution, by locating the liquid injection hole on the pressure release structure, it is possible to avoid the liquid injection hole occupying space on the case by itself. If the polar pillar structure is located on the case, a relatively large space for locating the polar pillar structure can be saved, which helps to increase the size of the polar pillar structure. Furthermore, since there is no need to perform special processing on the case to open the liquid injection hole on the case, it helps to reduce the structural complexity and processing difficulty of the case.

[0085] In some embodiments, the pressure release structure includes a pressure release body provided on the case and a third seat attached to the pressure release body, at least a portion of the liquid injection hole is formed on the third seat, and the sealing structure is fitted to the third seat.

[0086] In the above technical solution, a separately processed third base portion is provided, and the third base portion is attached to the pressure release body through an assembly process, and the sealing structure is fitted to the third base portion, thereby processing the third base portion into a shape that is compatible with the sealing structure, reducing the structural complexity of the pressure release body and facilitating the processing of the pressure release body.

[0087] In some embodiments, the case assembly includes a case defining a receiving cavity, the case having a polar pillar structure and a pressure release structure disposed on the case, the case including a mounting case wall spaced apart from the polar pillar structure and the pressure release structure, the flow path being disposed in the mounting case wall and including a liquid injection hole, and the sealing structure being fitted to the mounting case wall and configured to open or seal the liquid injection hole.

[0088] In the above technical solution, the liquid injection hole is arranged on the mounting case wall, not on the pressure release structure and the pole structure, thereby reducing the difficulty in processing the pressure release structure and the pole structure and the cost of processing the pressure release structure and the pole structure.

[0089] In some embodiments, the mounting case wall comprises a case wall portion and a fourth base portion attached to the case wall portion, at least a portion of the liquid injection hole is formed on the fourth base portion, and the sealing structure is fitted to the fourth base portion.

[0090] In the above technical solution, a separately processed fourth base is provided, the fourth base is attached to the case wall through an assembly process, and the sealing structure is fitted to the fourth base, thereby processing the fourth base into a shape that is compatible with the sealing structure, reducing the structural complexity of the case wall and facilitating the processing of the case wall.

[0091] In some embodiments, the case assembly includes a case defining a storage cavity, the case including a first case wall, a surface of the first case wall facing the storage cavity being an inner surface and a surface of the first case wall facing away from the storage cavity being an outer surface, the flow path including a liquid injection hole directly or indirectly provided in the first case wall, both ends of the liquid injection hole being an outer hole end and an inner hole end, the outer hole end and the inner hole end being arranged sequentially along a direction from the outer surface to the inner surface of the first case wall, and the inner hole end being located on a side of the inner surface of the first case wall facing away from the storage cavity.

[0092] In the above technical solution, the height of the liquid injection hole may be increased. This creates an extra storage space inside the liquid injection hole that can act as a buffer. If, for example, the electrolyte is about to overflow during the manufacturing, transportation, or use of the battery cell, the overflowing electrolyte can enter the storage space. This reduces the likelihood of the electrolyte overflowing from the liquid injection hole and helps to alleviate the problem of the overflowed electrolyte contaminating the first case wall and components on the first case wall. This also helps to increase the injection speed during manufacturing, improving the manufacturability of the battery cell and its reliability. Furthermore, because the height of the liquid injection hole is increased, if the level of the injected electrolyte reaches the inner edge of the liquid injection hole, it will be higher than the inner surface of the first case wall, which helps to increase the total amount of electrolyte injected into the case and further helps to extend the cycle life of the battery cell. It can be understood that as the electrolyte is consumed during use of the battery cell, the amount of electrolyte in the battery cell decreases, affecting the service life of the battery cell. Increasing the total amount of injected electrolyte helps to extend the service life of the battery cell. Furthermore, during use of the battery cell, the electrolyte generates gas after participating in a reaction, causing the pressure inside the case to rise. When the pressure reaches a certain level, reliability issues arise. When gas is generated inside the case, the remaining storage space in the liquid injection hole acts as a buffer for the gas, thereby alleviating the reliability issues caused by the pressure increase and improving the reliability of the battery cell.

[0093] In some embodiments, a mounting portion is provided on the first case wall, at least a portion of the mounting portion protruding from an outer surface of the first case wall away from the accommodating cavity, and the liquid injection hole is provided in the mounting portion.

[0094] In the above technical solution, by arranging the liquid injection hole on the mounting portion, it becomes easy for the inner end of the liquid injection hole to be positioned on the side of the inner surface of the first case wall away from the accommodating cavity.

[0095] In some embodiments, the inner end of the hole is located on an outer surface of the first case wall away from the receiving cavity.

[0096] In the above technical solution, the height of the inner end of the liquid injection hole can be further increased, so that more storage space is created below the liquid injection hole.

[0097] In some embodiments, a case assembly includes a case defining a receiving cavity, the case including a first case wall having a flow passage therethrough, the first case wall being an integrally formed cover plate or being integrally formed with at least one second case wall extending toward one side of a thickness of the first case wall.

[0098] The above technical solution can realize flexible design of the flow path position and widen the application range of the battery cell.

[0099] In a second aspect, an embodiment of the present application further provides a battery comprising a current collecting member and a battery cell described in any one of the above solutions, wherein the battery has a plurality of battery cells, at least two of which are electrically connected via the current collecting member.

[0100] The above technical solution improves both the usage reliability and service life of the battery cell according to the embodiment of the present application, which is helpful in improving the usage reliability and service life of the battery.

[0101] In a third aspect, an embodiment of the present application further provides an electrical device comprising the battery according to any one of the above solutions.

[0102] In the above technical solution, the performance of the battery is improved, which helps to improve the power consumption performance during the operation of the electrical device. [Brief explanation of the drawings]

[0103] In order to more clearly explain the technical solutions of the embodiments of the present application, the drawings used in the embodiments are briefly introduced below. It should be understood that the following drawings only illustrate some embodiments of the present application and should not be considered as limiting the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without any creative work.

[0104] [Figure 1] 1 is a structural schematic diagram of a vehicle according to some embodiments of the present application. [Figure 2] 1 is an exploded view of the structure of a battery according to some embodiments of the present application. [Figure 3] 1 is a structural schematic diagram of a battery cell according to some embodiments of the present application; [Figure 4] 1 is an orthographic schematic view of a battery cell according to some embodiments of the present application; FIG. [Figure 5] FIG. 5 is a cross-sectional view taken along line KK in FIG. [Figure 6] FIG. 6 is a partial enlarged view of part H shown in FIG. 5. [Figure 7] 1 is a partial schematic diagram of a battery cell according to some embodiments of the present application. [Figure 8] FIG. 8 is a partial orthographic schematic view of the battery cell shown in FIG. 7. [Figure 9] FIG. 9 is a cross-sectional view taken along line GG in FIG. 8. [Figure 10] FIG. 8 is a partial schematic view of the substructure shown in FIG. 7. [Figure 11] FIG. 2 is a front view of a first structural member according to some embodiments of the present application. [Figure 12] FIG. 12 is a three-dimensional view of the first structural member shown in FIG. [Figure 13] 13 is a schematic diagram of the engagement between the first structural member and the base shown in FIG. 12. FIG. [Figure 14] FIG. 14 is a cross-sectional view taken along the line SS in FIG. [Figure 15] FIG. 2 is a front view of a first structural member according to some embodiments of the present application. [Figure 16]FIG. 16 is a three-dimensional view of the first structural member shown in FIG. 15. [Figure 17] 1 is a partial cross-sectional view of a battery cell according to some embodiments of the present application. [Figure 18] 1 is a partial cross-sectional view of a battery cell according to some embodiments of the present application. [Figure 19] 1 is a partial cross-sectional view of a battery cell according to some embodiments of the present application. [Figure 20] FIG. 20 is a partial enlarged view of the circled portion F1 in FIG. 19. [Figure 21] 1 is a partial cross-sectional view of a battery cell according to some embodiments of the present application. [Figure 22] 1A and 1B are schematic diagrams of mating between a pole body and a conductive portion according to some embodiments of the present application; [Figure 23] 1A and 1B are schematic diagrams of mating between a pole body and a conductive portion according to some embodiments of the present application; [Figure 24] 1 is an orthographic schematic view of a battery cell according to some embodiments of the present application; FIG. [Figure 25] 1 is a partial cross-sectional view of a battery cell according to some embodiments of the present application. [Figure 26] 1 is a partial cross-sectional view of a battery cell according to some embodiments of the present application. [Figure 27] 1 is a partial cross-sectional view of a battery cell according to some embodiments of the present application. [Figure 28] 1 is a partial cross-sectional view of a battery cell according to some embodiments of the present application. [Figure 29] 1 is a partial cross-sectional view of a battery cell according to some embodiments of the present application. [Figure 30] 1 is a partial cross-sectional view of a battery cell according to some embodiments of the present application. [Figure 31] 1 is a structural schematic diagram of a battery cell according to some embodiments of the present application; [Figure 32] FIG. 32 is a partially enlarged view of FIG. 31. [Figure 33] 1 is a three-dimensional view of a battery cell according to some embodiments of the present application. [Figure 34]FIG. 34 is a three-dimensional view of the battery cell shown in FIG. 33 viewed from another angle. [Figure 35] FIG. 34 is a partial enlarged view of the circled portion J in FIG. 33. [Figure 36] 1 is a partial cross-sectional view of a battery cell according to some embodiments of the present application. [Figure 37] 1 is a schematic diagram of the mating of a battery cell and a current collecting member according to some embodiments of the present application. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0105] In order to make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application are clearly described below in conjunction with the accompanying drawings in the embodiments of the present application. Of course, the described embodiments are only a part of the embodiments, not all of the embodiments of the present application. Based on the embodiments of the present application, all other embodiments that a person skilled in the art can obtain without creative work shall fall within the scope of protection of the present application.

[0106] Unless otherwise defined, all technical and specialty terms used in this application have the same meaning as commonly understood by one skilled in the art to which this application pertains. The terms used in this specification are intended to describe specific embodiments only and are not intended to limit this application. The terms "comprises," "includes," and variations thereof in this specification and claims, as well as in the above-mentioned brief description of the drawings, are intended to include a non-exclusive inclusion. Terms such as "first," "second," etc. in this specification and claims, or in the above-mentioned accompanying drawings, are used to distinguish between different objects, not to describe a particular order or subordinate relationship.

[0107] When an "embodiment" is mentioned in this application, it means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification do not necessarily all refer to the same embodiment, nor do they refer to separate or alternative embodiments or mutually exclusive alternative embodiments.

[0108] In the description of this application, unless otherwise clearly defined and limited, the terms "attached," "coupled," "connected," and "mounted" should be understood in a broad sense to mean, for example, a fixed connection, a detachable connection, an integral connection, a direct connection, an indirect connection via an intermediate medium, or an internal connection between two elements. Those skilled in the art may understand the specific meanings of the above terms in this application depending on the specific situation.

[0109] The term "and / or" in this application merely describes the relationship between related objects and indicates that a three-way relationship may exist. For example, A and / or B may indicate that there are three situations: A exists alone, A and B exist together, or B exists alone. Also, in this application, the symbol " / " generally indicates that the related objects before and after it are in an "or" relationship.

[0110] In the embodiments of the present application, the same reference numerals refer to the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments will be omitted. It should be understood that the dimensions such as thickness, length, width, etc. of various components in the embodiments of the present application shown in the accompanying drawings, as well as the dimensions such as thickness, length, width, etc. of the overall integrated device, are merely examples and are not intended to limit the present application.

[0111] The term "plurality" as used in this application refers to two or more (including two).

[0112] In this application, battery cells include, but are not limited to, lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium ion batteries, sodium ion batteries, and magnesium ion batteries. Battery cells may be cylindrical, flat, rectangular, or have other shapes, but are not limited to these. Battery cells are generally classified into three types depending on their packaging: cylindrical battery cells, prismatic battery cells, and soft-pack battery cells, but are not limited to these.

[0113] The battery referred to in the embodiments of this application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery referred to in this application may include a battery module or a battery pack. A battery module typically includes multiple battery cells. A battery pack typically includes a housing for enclosing one or more battery cells or one or more battery modules. The housing can prevent liquids or other foreign objects from affecting the charging and discharging of the battery cells.

[0114] A battery cell includes a case for housing the cell assembly and the electrolyte, the cell assembly, and the electrolyte. The cell assembly includes at least one electrode assembly composed of a positive electrode plate, a negative electrode plate, and a separator. The electrode assembly may have a wound structure or a stacked structure. The battery cell operates primarily through the transfer of metal ions between the positive and negative electrode plates.

[0115] The positive electrode plate may typically include a positive electrode current collector and a positive electrode active material layer. The positive electrode active material layer is applied directly or indirectly to the positive electrode current collector, and the positive electrode current collector without the positive electrode active material layer protrudes beyond the positive electrode current collector with the positive electrode active material layer applied thereto, and the positive electrode current collector without the positive electrode active material layer is referred to as a positive electrode tab. Taking a lithium-ion battery as an example, the positive electrode current collector may be made of aluminum, and the positive electrode active material layer may be made of lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide.

[0116] The negative electrode plate may typically include a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is applied directly or indirectly to the negative electrode current collector, and the negative electrode current collector not coated with the negative electrode active material layer protrudes beyond the negative electrode current collector coated with the negative electrode active material layer, and the negative electrode current collector not coated with the negative electrode active material layer is referred to as a negative electrode tab. Examples of materials for the negative electrode current collector include copper, and examples of materials for the negative electrode active material layer include carbon and silicon.

[0117] To ensure a large current can flow without fusing, multiple positive electrode tabs are stacked to form a positive electrode tab portion, and multiple negative electrode tabs are stacked to form a negative electrode tab portion. Electrode posts are provided on the case, and the positive electrode tab portion is electrically connected to the positive electrode post, and the negative electrode tab portion is electrically connected to the negative electrode post. For example, the tab portion may be welded to the electrode post to form a direct electrical connection between the tab portion and the electrode post. As another example, the cell assembly may include an intermediate connection sheet. The tab portion is welded to the intermediate connection sheet, and the intermediate connection sheet is welded to the electrode post to form an indirect electrical connection between the tab portion and the electrode post.

[0118] The separator material may be, but is not limited to, polypropylene or polyethylene.

[0119] In the battery cells of the related art, the electrolyte generates gas after participating in a reaction, which causes the pressure inside the case to rise. When the pressure reaches a certain level, reliability issues arise. Furthermore, as the electrolyte is consumed during use, the amount of electrolyte inside the case decreases, which affects the service life of the battery cell.

[0120] Therefore, an embodiment of the present application provides a battery cell including a case assembly that defines a storage cavity and has a flow path that communicates with the storage cavity, and a sealing structure that is fitted to the case assembly and configured to open or seal the flow path.

[0121] Therefore, during the production of a battery cell, the flow path is opened using a sealing structure. At this time, electrolyte is injected into the accommodating cavity through the flow path. After the electrolyte is injected, the flow path is closed and sealed using a sealing structure, preventing electrolyte overflow and allowing the battery cell to operate normally. During use, as the electrolyte is consumed, the amount of electrolyte in the case assembly decreases, affecting the service life of the battery cell. Therefore, by periodically opening the flow path in the sealing structure, electrolyte can be added and replenished through the flow path to extend the service life of the battery cell. During use, the electrolyte generates gas after participating in a reaction, which increases the pressure in the case assembly. When the pressure reaches a certain level, reliability issues arise. Therefore, by periodically opening the flow path in the sealing structure during use, pressure in the accommodating cavity can be periodically released through the flow path, improving the reliability of the battery cell.

[0122] In summary, the battery cell of the present application has a sealing structure that can open and close the flow path, so that during normal use of the battery cell, the sealing structure closes and seals the flow path to meet the requirements for sealing the battery cell, and during manufacturing or maintenance of the battery cell, the sealing structure opens the flow path to inject or replenish electrolyte through the flow path and periodically release high pressure within the battery cell, in order to meet the manufacturing requirements of the battery cell and at the same time improve the service life and reliability of the battery cell.

[0123] An embodiment of the present application provides an electric device that uses a battery as a power source. The electric device may include, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, an electric motorcycle, an electric car, a steamship, an aircraft, etc. Among these, the electric toy may include, for example, a game console, an electric car toy, an electric boat toy, an electric plane toy, or other stationary or portable electric toys, and the aircraft may include, for example, an airplane, a rocket, a space shuttle, a spaceship, etc.

[0124] For convenience of explanation, the following embodiment will be described taking a vehicle 1000 as an example of an electric device according to an embodiment of the present application.

[0125] Please refer to FIG. 1 , which is a structural schematic diagram of a vehicle 1000 according to some embodiments of the present application. The vehicle 1000 may be a fuel vehicle, a natural gas vehicle, or a new energy vehicle. The new energy vehicle may be a pure electric vehicle, a hybrid vehicle, a range-extender vehicle, etc. A battery 100 is provided inside the vehicle 1000, and the battery 100 may be provided at the bottom, head, or tail of the vehicle 1000. The battery 100 is used to supply power to the vehicle 1000. For example, the battery 100 may be used as an operating power source for the vehicle 1000. The vehicle 1000 may further include a controller 200 and a motor 300. The controller 200 controls the battery 100 to supply power to the motor 300. For example, the controller 200 is used when operating power is required for starting, navigating, and driving the vehicle 1000.

[0126] In some embodiments of the present application, the battery 100 may be used as an operating power source for the vehicle 1000, or may be used as a power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0127] Please refer to FIG. 2 , which is an exploded view of a battery 100 according to some embodiments of the present application. The battery 100 includes a housing 101 and a plurality of battery cells 102 housed within the housing 101. The housing 101 provides an assembly space for the battery cells 102 and may have various structures. In some embodiments, the housing 101 includes a first housing body 1011 and a second housing body 1012 that are placed over each other and together define an assembly space for accommodating the battery cells 102. The second housing body 1012 may have a hollow structure with one end open, and the first housing body 1011 may have a plate-like structure. The first housing body 1011 covers the open side of the second housing body 1012 so that the first housing body 1011 and the second housing body 1012 together define the assembly space. The first housing body 1011 and the second housing body 1012 may both have a hollow structure with one side open, with the open side of the first housing body 1011 covering the open side of the second housing body 1012. Naturally, the housing 101 formed by the first housing body 1011 and the second housing body 1012 may have various shapes, such as a cylindrical shape or a rectangular shape.

[0128] In the battery 100, the multiple battery cells 102 may be connected in series, parallel, or a mixed connection. A mixed connection means that the multiple battery cells 102 may be connected in series or in parallel. The multiple battery cells 102 may also be directly connected in series, parallel, or a mixed connection so that the entire battery cell set is housed within the housing 101. Of course, the battery 100 may be configured such that the multiple battery cells 102 are first connected in series, parallel, or a mixed connection to form a battery module, and then the multiple battery modules are connected in series, parallel, or a mixed connection to form an integrated battery module and housed within the housing 101. The battery 100 may further include other structures. For example, the battery 100 may further include a current collecting member for achieving electrical connection between the multiple battery cells 102.

[0129] Each battery cell 102 may be a secondary battery or a primary battery, and may be, but is not limited to, a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery. The battery cells 102 may be cylindrical, flat, rectangular, etc. For example, see the embodiment shown in FIG. 3. The length direction of the battery cell 102 is a first direction X, the width direction of the battery cell 102 is a second direction Y, and the height direction of the battery cell 102 is a third direction Z, and the first direction X, the second direction Y, and the third direction Z are perpendicular to each other two by two.

[0130] According to some embodiments of the present application, referring to Figures 4 to 6, the battery cell 102 includes a case assembly 1021 that defines an accommodating cavity 1A and has a flow path 1021A that communicates with the accommodating cavity 1A, and a sealing structure 1022 that is fitted to the case assembly 1021 to open or seal the flow path 1021A, i.e., that has the function of opening the flow path 1021A and also the function of closing the flow path 1021A by fitting with the case 1.

[0131] During the production of the battery cell 102, the sealing structure 1022 opens the flow path 1021A. At this time, electrolyte is injected into the receiving cavity 1A through the flow path 1021A. After the electrolyte is injected, the sealing structure 1022 closes and seals the flow path 1021A, preventing electrolyte overflow and allowing the battery cell 102 to operate normally. During use of the battery cell 102, as the electrolyte is consumed, the amount of electrolyte in the case assembly 1021 decreases, affecting the service life of the battery cell 102. Therefore, by periodically opening the flow path 1021A in the sealing structure 1022, electrolyte can be added to the receiving cavity 1A through the flow path 1021A to replenish it, thereby extending the service life of the battery cell 102. During use of the battery cell 102, the electrolyte reacts and generates gas, which increases the pressure inside the case assembly 1021. When the pressure reaches a certain level, reliability issues arise. Therefore, by periodically opening the flow path in the sealing structure 1022 during use of the battery cell 102, the pressure in the accommodating cavity 1A can be periodically released via the flow path 1021A, thereby improving the reliability of use of the battery cell 102.

[0132] In summary, the battery cell 102 of the embodiment of the present application has a sealing structure 1022 that can open and close the flow path 1021A. This allows the sealing structure 1022 to close and seal the flow path 1021A during normal use of the battery cell 102 to meet the requirements for sealing and using the battery cell 102. Furthermore, during manufacturing or maintenance of the battery cell 102, the sealing structure 1022 opens the flow path 1021A, allowing electrolyte to be injected or replenished through the flow path 1021A and periodically releasing high pressure within the battery cell 102, in order to meet the manufacturing requirements for the battery cell 102 and improve the service life and reliability of the battery cell 102.

[0133] It should be noted that the sealing structure 1022 and the case assembly 1021 may be fitted together in various ways to allow the sealing structure 1022 to open or close the flow path 1021A.

[0134] For example, in some embodiments, the sealing structure 1022 may be configured to be removably mated to the case assembly 1021. When the sealing structure 1022 and the case assembly 1021 are assembled in place, the sealing structure 1022 can seal the flow path 1021A. When the sealing structure 1022 is removed from the case assembly 1021, the flow path 1021A can be opened.

[0135] Alternatively, in some other embodiments, the sealing structure 1022 and the case assembly 1021 are always connected, and the sealing structure 1022 can move between an open position and a closed position relative to the case assembly 1021. When the sealing structure 1022 moves to the open position, it can open the flow path 1021A, and when the sealing structure 1022 moves to the closed position, it can close the flow path 1021A. For example, the sealing structure 1022 can be moved between the two positions by rotation or translation.

[0136] Alternatively, in some other embodiments, the sealing structure 1022 and the case assembly 1021 are always connected, and the sealing structure 1022 is deformable between a first form and a second form relative to the case assembly 1021. When the sealing structure 1022 is deformed to the first form, it can open the flow path 1021A, and when the sealing structure 1022 is deformed to the second form, it can close the flow path 1021A.

[0137] Here, when the sealing structure 1022 and the case assembly 1021 are removably fitted together, during the production stage of the battery cell 102, the flow path 1021A is open before the sealing structure 1022 is attached. At this time, electrolyte can be injected into the accommodating cavity 1A through the flow path 1021A. After the electrolyte is injected, the sealing structure 1022 is attached to the case assembly 1021, closing and sealing the flow path 1021A, thereby preventing the electrolyte from overflowing and allowing the battery cell 102 to be used normally. During use of the battery cell 102, the sealing structure 1022 can be periodically removed from the case assembly 1021, opening the flow path 1021A, and adding and replenishing electrolyte to the accommodating cavity 1A through the flow path 1021A, thereby extending the service life of the battery cell 102. Periodically releasing the high pressure in the accommodating cavity 1A through the flow path 1021A can improve the reliability of the battery cell 102.

[0138] Therefore, by detachably disposing the sealing structure 1022 relative to the case assembly 1021, compared to a solution in which the sealing structure 1022 is movable relative to the case assembly 1021 to open and close the flow path 1021A, this simplifies the connection method between the sealing structure 1022 and the case assembly 1021, simplifies the design and processing of the case assembly 1021, and helps to improve the sealing reliability of the sealing structure 1022 relative to the case assembly 1021. Furthermore, compared to a solution in which the sealing structure 1022 is switched between different shapes to open and close the flow path 1021A, this reduces the structural complexity of the sealing structure 1022 itself, reduces the difficulty of processing the sealing structure 1022, and helps to cut processing costs.

[0139] The position and shape of the sealing structure 1022 can be flexibly designed, and some optional examples are introduced below.

[0140] 8-9, in some embodiments of the present application, the sealing structure 1022 comprises two separate parts, a first structural member 61 and a second structural member 62. The second structural member 62 is sealingly fitted to the flow path 1021A, and the first structural member 61 is lockingly fitted to the case assembly 1021 and is located on the side of the second structural member 62 away from the accommodating cavity 1A to restrict the second structural member 62 to a position that seals the flow path 1021A.

[0141] Here, the sealing structure 1022 seals the flow path 1021A via at least the second structural component 62. For example, only the second structural component 62 plays a role in sealing the flow path 1021A, and the first structural component 61 does not play a role in sealing the flow path 1021A. As another example, both the second structural component 62 and the first structural component 61 play a role in sealing the flow path 1021A.

[0142] Here, the lock engagement between the first structural member 61 and the case assembly 1021 can be unlocked. When the first structural member 61 is lock-engaged with the case assembly 1021, the first structural member 61 holds the second structural member 62 to restrict the second structural member 62 to a position that seals the flow path 1021A. When the first structural member 61 is unlocked from the case assembly 1021, the first structural member 61 can be removed from the case assembly 1021 to release the restriction on the second structural member 62. By removing the second structural member 62 (or by simultaneously removing the first structural member 61 and the second structural member 62), the flow path 1021A can be opened, allowing maintenance of the flow path 1021A, for example, to inject electrolyte via the flow path 1021A or to release pressure using the flow path 1021A.

[0143] It should be understood in a broad sense that "the first structural member 61 restricts the second structural member 62 to a position where it blocks the flow path 1021A" means, for example, that when the first structural member 61 is lock-fitted into the case assembly 1021, the second structural member 62 and the first structural member 61 have a connection relationship through direct or indirect contact, so the second structural member 62 does not move at all under the position-restricting action of the first structural member 61, and the second structural member 62 always blocks the flow path 1021A; as another example, when the first structural member 61 is lock-fitted into the case assembly 1021, the second structural member 62 is positioned at a distance from the first structural member 61 and does not have a connection relationship through direct or indirect contact, so the second structural member 62 can move a certain distance relative to the first structural member 61, but within that distance, the second structural member 62 always blocks the flow path 1021A. Therefore, the position where second structural member 62 seals flow path 1021A is not limited to one point, but may be any position within a range. As long as second structural member 62 is in a state where it seals flow path 1021A, any position of second structural member 62 will seal flow path 1021A.

[0144] Therefore, by providing the second structural member 62 in the sealing structure 1022, it can serve to seal the flow path 1021A, and by providing the first structural member 61, it can serve to limit the position of the second structural member 62, preventing the second structural member 62 from escaping in a direction away from the accommodating cavity 1A and ensuring that the second structural member always seals the flow path 1021A, thereby improving the sealing effect of the second structural member 62 on the flow path 1021A. Furthermore, because the sealing structure 1022 is composed of the first structural member 61 and the second structural member 62, the design of the first structural member 62 can be done without considering or excessively considering sealing, and can instead focus primarily on the convenience and reliability of the lock, thereby improving the reliability and convenience of the lock of the first structural member 61. On the other hand, when designing the second structural member 62, it is possible to not consider locking or to give excessive consideration to locking, and to mainly consider the sealing of the flow path 1021A, thereby improving the reliability of sealing the flow path 1021A by the second structural member 62.

[0145] In this way, the sealing structure 1022 of the embodiment of the present application can better achieve the dual effects of locking and sealing by using a combination of two structural members and assigning different functions to the two structural members. Because there are relatively few factors to consider in the design of the first structural member 61 and the second structural member 62, this helps to relatively simplify the design of the first structural member 61 and the second structural member 62 and makes the first structural member 61 and the second structural member 62 easier to process. In short, in the embodiment of the present application, achieving both sealing and locking functions does not require designing a single structural member that is very complex and difficult to process, nor does it require sacrificing some locking performance in order for one structural member to also perform sealing performance. At the same time, it does not require sacrificing some sealing performance in order for one structural member to also perform locking performance.

[0146] 9 , the first structural member 61 is connected to the second structural member 62. In this manner, during installation, the first structural member 61 is first assembled and connected to the second structural member 62 to form an assembly, and then the assembly consisting of the first structural member 61 and the second structural member 62 can be attached toward the flow path 1021A of the case assembly 1021, thereby improving the efficiency of assembling the sealing structure 1022 to the case assembly 1021. Furthermore, because the first structural member 61 and the second structural member 62 are connected to each other, the first structural member 61 reliably restricts the position of the second structural member 62, and the first structural member 61 can more stably position the second structural member 62 in a position that seals the flow path 1021A.

[0147] There is no limitation on the method of connecting the first structural member 61 and the second structural member 62. For example, they may be connected in a removable manner (for example, by screwing, insertion, engagement, or interference fit), or in a non-removable manner (for example, by adhesion or welding), or may be connected directly or indirectly (for example, by providing an intermediate part to connect the two or by providing a fastener to fix the two), and may be specifically designed according to actual requirements.

[0148] In some embodiments, the first structural member 61 and the second structural member 62 are removably connected. Therefore, if one of the first structural member 61 and the second structural member 62 is damaged, it can be removed and replaced, thereby reducing the maintenance costs of the sealing structure 1022.

[0149] In some embodiments, the connection between the first structural member 61 and the second structural member 62 keeps the first structural member 61 and the second structural member 62 connected when the sealing structure 1022 is removed from the case assembly 1021. In other words, the connection between the first structural member 61 and the second structural member 62 allows the second structural member 62 to be removed from the case assembly 1021 together with the first structural member 61 when the first structural member 61 is removed from the case assembly 1021. In this way, when the first structural member 61 is unlocked and removed from the case assembly 1021, the second structural member 62 remains connected to the first structural member 61, and therefore the second structural member 62 is released from the case assembly 1021 together with the first structural member 61. This improves the efficiency of removing the sealing structure 1022 from the case assembly 1021 and facilitates maintenance work.

[0150] Furthermore, regardless of whether the first structural member 61 and the second structural member 62 are removably connected or non-removably connected, it is possible to achieve the following: "Due to the connection between the first structural member 61 and the second structural member 62, when the sealing structure 1022 is removed from the case assembly 1021, the first structural member 61 and the second structural member 62 remain connected."

[0151] However, the present application is not limited to this. In another embodiment of the present application, the first structural member 61 and the second structural member 62 are connected by sequentially removing the first structural member 61 and the second structural member 62 from the case assembly 1021, that is, during installation, the first structural member 61 and the second structural member 62 can both be attached to the case assembly 1021, but when the first structural member 61 is pulled out, the second structural member 62 is separated from the first structural member 61, so it is necessary to first remove the first structural member 61 from the case assembly 1021, and then remove the second structural member 62 from the case assembly 1021.

[0152] 9, the first structural member 61 has a first mating portion 611 on the side facing the second structural member 62, and the second structural member 62 has a second mating portion 621 on the side facing the first structural member 61. One of the first mating portion 611 and the second mating portion 621 has a convex structure and the other has a concave structure, with the convex structure mated with the concave structure. Therefore, the first structural member 61 can be quickly assembled with the second structural member 62 by the concave-convex insertion, which facilitates the design and processing of both and reduces the processing costs of both.

[0153] When the first structural member 61 and the second structural member 62 are fitted together via a convex structure and a concave structure, there are various ways to achieve the state where "when the sealing structure 1022 is removed from the case assembly 1021, the first structural member 61 and the second structural member 62 remain connected." For example, in some examples, the convex structure and the concave structure are tightly fitted together, and the tightness of the tight fit is greater than the tightness of the tight fit between the second structural member 62 and the flow path 1021A. For example, in other examples, the convex structure and the concave structure are threadedly engaged (for example, the convex structure is a threaded bolt and the concave structure is a screw hole). For example, in other examples, the convex structure and the concave structure are fitted together while being positionally restricted by a position restricting structure (such as a barb structure or a shoulder structure) to prevent the convex structure from escaping from the concave structure. In this way, when installing, the first structural member 61 and the second structural member 62 can both be mounted inside the case assembly 1021, and when removing, the second structural member 62 detaches from the case assembly 1021 together with the first structural member 61, thereby improving the assembly and removal efficiency of the entire sealing structure 1022.

[0154] Furthermore, if the first structural member 61 and the second structural member 62 are connected by fasteners (screws, rivets, etc.), or if the first structural member 61 and the second structural member 62 are fixedly connected by adhesive bonding or welding, etc., it is also possible to achieve the following: "When the sealing structure 1022 is removed from the case assembly 1021, the first structural member 61 and the second structural member 62 remain connected."

[0155] When the first structural member 61 and the second structural member 62 are fitted to the convex structure via the convex structure, to realize the connection between the first structural member 61 and the second structural member 62 such that the first structural member 61 and the second structural member 62 are sequentially removed from the case assembly 1021, for example, it is possible that the convex structure and the concave structure are interference-fitted, and the tightness of this interference fit is lower than the tightness of the interference fit between the second structural member 62 and the flow path 1021A. During installation, both the first structural member 61 and the second structural member 62 can be attached to the case assembly 1021, but when the first structural member 61 is pulled out, the second structural member 62 is separated from the first structural member 61. Therefore, it is necessary to first remove the first structural member 61 from the case assembly 1021, and then remove the second structural member 62 from the case assembly 1021.

[0156] 9 and 10 , at least a portion of the first structural member 61 is fitted within the case assembly 1021. That is, the first structural member 61 may be only partially fitted within the case assembly 1021, or the first structural member 61 may be completely fitted within the case assembly 1021. Therefore, fitting at least a portion of the first structural member 61 within the case assembly 1021 improves the tightness of the fit between the sealing structure 1022 and the case assembly 1021 and helps reduce the space outside the case assembly 1021 occupied by the first structural member 61. When the first structural member 61 is completely fitted within the case assembly 1021 and does not protrude from the surface of the case assembly 1021, the possibility of damage to or erroneous unlocking of the first structural member 61 is reduced, and the reliability of sealing of the flow path 1021A can be improved.

[0157] In some embodiments of the present application, the first structural member 61 is configured to be able to be locked and unlocked to and from the case assembly 1021 by a rotational movement. Therefore, the method for locking and unlocking the first structural member 61 is simple and easy to operate.

[0158] In some embodiments, as shown in FIGS. 9 and 10 , the first structural member 61 may have a tool fitting hole 612. For example, the tool fitting hole 612 may be located on the surface of the first structural member 61 away from the second structural member 62. For example, the tool fitting hole 612 may be a straight hole, a cross hole, a hexagonal hole, or the like so that the first structural member 61 can be locked and unlocked by rotating the first structural member 61 using a tool. Furthermore, at least a portion of the first structural member 61 does not need to protrude from the surface of the case assembly 1021 in order to rotate the first structural member 61. The rotation of the first structural member 61 can also be achieved when at least a portion of the first structural member 61 is fitted within the case assembly 1021.

[0159] However, the present application is not limited to this. Naturally, when it is necessary for the first structural member 61 to protrude from the surface of the case assembly 1021, at least a portion of the first structural member 61 may protrude outward from the surface of the case assembly 1021. For example, when the first structural member 61 does not have a tool fitting hole 612, a portion of the first structural member 61 may be formed in a non-circular shape (for example, a square, a hexagon, or the like) and protrude outward from the surface of the case assembly 1021, so that a force can be applied to the non-circular portion of the first structural member 61 using a tool to rotate the first structural member 61 and perform a locking or unlocking operation.

[0160] For example, when the first structural member 61 is attached by fitting it into the case assembly 1021, a tool fitting hole 612 is provided on the first structural member 61 to facilitate locking and unlocking of the first structural member 61. When the first structural member 61 protrudes into the case assembly 1021, the tool fitting hole 612 may or may not be provided on the first structural member 61.

[0161] 10 , the first structural member 61 may have a positioning structure 613. For example, the positioning structure 613 may be disposed on the surface of the first structural member 61 away from the second structural member 62. For example, the positioning structure 613 may be a pit, a protrusion, a pattern, or the like, which can be used to guide the installation position of the first structural member 61 and quickly align the first structural member 61 to the installation position. And / or, the positioning structure 613 can be used to detect the rotation angle of the first structural member 61 to ensure that the first structural member 61 has been rotated to a predetermined position and ensure the reliability of the lock.

[0162] 11 and 12 , in some embodiments of the present application, the first structural member 61 includes a central portion 614 disposed corresponding to the flow path 1021A, and a locking portion 615 located in an outer peripheral region of the central portion 614. Referring to FIGS. 13 and 14 , the case assembly 1021 is formed with stopper portions 10211 and escape holes 10212 that are alternately disposed around the flow path 1021A. A receiving groove 10213 is formed on the side of the stopper portion 10211 that is close to the accommodating cavity 1A, and the escape hole 10212 passes through the surface of the case assembly 1021 on the side away from the accommodating cavity 1A and communicates with the receiving groove 10213, and the locking portion 615 rotatably moves in and out of the receiving groove 10213 through the escape hole 10212.

[0163] During assembly, the locking portion 615 can be aligned with the escape hole 10212 and sunk into the escape hole 10212. When the locking portion 615 reaches a position corresponding to the receiving groove 10213, the first structural member 61 can be rotated to insert the locking portion 615 into the receiving groove 10213. At this time, the stopper portion 10211 stops on the side of the locking portion 615 away from the accommodating cavity 1A, preventing the locking portion 615 from escaping in a direction away from the accommodating cavity 1A, and the first structural member 61 and the case assembly 1021 are locked together. When the first structural member 61 is rotated again to move the locking portion 615 from the receiving groove 10213 to the escape hole 10212, the locking portion 615 is no longer stopped by the stopper portion 10211, and the first structural member 61 and the case assembly 1021 can be unlocked. At this time, by dragging the first structural member 61 in a direction away from the accommodating cavity 1A, the engaging portion 615 can be moved out of the avoidance hole 10212, thereby realizing removal of the first structural member 61 from the case assembly 1021.

[0164] Therefore, the first structural member 61 and the case assembly 1021 can be locked and unlocked simply by rotating the first structural member 61 without any other excessive operations, reducing the difficulty of the operation and improving the efficiency of removing and assembling the first structural member 61. Furthermore, the structures of the first structural member 61 and the case assembly 1021 are relatively simple, making them easy to process. Furthermore, because the locking portion 615 is located around the central portion 614, it does not affect the design of the central portion 614. The size and shape of the central portion 614 can be flexibly designed according to the mating requirements with the flow channel 1021A, improving design flexibility. Furthermore, because the locking portion 615 can accommodate the surrounding area of ​​the flow channel 1021A, it does not affect the design of the size and shape of the flow channel 1021A, and the design requirements of the flow channel 1021A itself can be met.

[0165] In some embodiments of the present application, as shown in FIGS. 13 and 14 , there are a plurality of avoidance holes 10212, which are arranged at intervals around the flow path 1021A, and a stopper portion 10211 is provided between each pair of adjacent avoidance holes 10212, thereby realizing that the stopper portions 10211 and the avoidance holes 10212 are arranged alternately along the circumferential direction of the flow path 1021A. There are a plurality of locking portions 615, which are arranged at intervals around the central portion 614. The locking portions 615 are arranged corresponding to the respective avoidance holes 10212. During assembly, the locking portions 615 are aligned with the respective avoidance holes 10212, i.e., the locking portions 615 correspond one by one to the respective avoidance holes 10212. The first structural member 61 is rotated, and the plurality of engaging portions 615 are rotated to the sides of the plurality of stopper portions 10211 that are closer to the accommodating cavity 1A.

[0166] Therefore, the cooperation of the multiple locking portions 615 and the multiple stopper portions 10211 can improve the reliability of the locking engagement between the first structural member 61 and the case assembly 1021. Furthermore, the multiple locking portions 615 are spaced apart, allowing the electrolyte to pass through the spaces between adjacent locking portions 615, thereby alleviating the problem of electrolyte pooling at the position of engagement due to locking and improving the reliability of the battery cell 102.

[0167] Of course, the present application is not limited thereto. For example, in another embodiment of the present application, the first structural member 61 and the case assembly 1021 may be arranged to be lockably fitted with each other using a threaded structure, so that the first structural member 61 can be locked and unlocked from the case assembly 1021 by a rotational movement. Alternatively, the locking and unlocking of the case assembly 1021 may be achieved without rotating the first structural member 61. For example, the case assembly 1021 may be arranged as a relatively complex structure to achieve switching between locking and unlocking. Illustratively, the case assembly 1021 may include a locking mechanism that can be changed to a locked state that locks the first structural member 61 and to an unlocked state that releases the first structural member 61.

[0168] 9 , the case assembly 1021 includes a support portion 10214. For example, the support portion 10214 is disposed around a portion of the flow path 1021A (e.g., the second passage portion A2). The second structural member 62 includes a lap joint 622 that is lap-joined to the side of the support portion 10214 away from the accommodating cavity 1A and supported by the side of the first structural member 61 close to the accommodating cavity 1A. That is, the lap joint 622 is lap-joined to the outside of the support portion 10214 (i.e., the side away from the accommodating cavity 1A) and supports the first structural member 61 from the inside (i.e., the side close to the accommodating cavity 1A). Alternatively, in another embodiment, if the case assembly 1021 includes a support portion 10214 arranged around the flow path 1021A, the first structural member 61 may be lap-joined to the outside of the support portion 10214 (i.e., the side away from the accommodating cavity 1A).

[0169] Therefore, the action of the support portion 10214 can limit the limit position to which the first structural member 61 can move in a direction approaching the accommodating cavity 1A, and the action of the stopper portion 10211 can limit the limit position to which the first structural member 61 can move in a direction away from the accommodating cavity 1A.Therefore, the joint action of the stopper portion 10211 and the support portion 10214 allows the first structural member 61 to be stably positioned in the locked position where it is locked and engaged with the case assembly 1021, improving the reliability of the lock engagement.

[0170] For example, during the assembly process of the sealing structure 1022, when the first structural member 61 or the second structural member 62 reaches a position where it is lap-joined to the support portion 10214, the locking portion 615 in the avoidance hole 10212 reaches a position corresponding to the receiving groove 10213, i.e., the first structural member 61 reaches a position where it can rotate. Specifically, during assembly, the locking portion 615 of the first structural member 61 is aligned with the avoidance hole 10212 on the case assembly 1021, and the first structural member 61 and the second structural member 62 are pushed toward the accommodating cavity 1A. When the first structural member 61 or the second structural member 62 is lap-joined to the support portion 10214, the support of the support portion 10214 prevents the first structural member 61 and the second structural member 62 from moving toward the accommodating cavity 1A. At this time, the locking portion 615 of the first structural member 61 reaches a position corresponding to the receiving groove 10213, and locking can be achieved by rotating the first structural member 61 to insert the locking portion 615 into the receiving groove 10213. Therefore, the support portion 10214 also serves as a positioning function during the assembly process, making it easier for the worker to know that the locking portion 615 has reached a position corresponding to the receiving groove 10213. At this time, the first structural member 61 can be rotated and locked, improving the convenience of assembly.

[0171] However, the present application is not limited to this. If the case assembly 1021 includes a support structure located on the side of the receiving groove 10213 closest to the accommodating cavity 1A, the support portion 10214 may be omitted. In this case, the worker can determine for themselves whether the locking portion 615 corresponds to the receiving groove 10213. If it corresponds to the receiving groove 10213, the worker can rotate the first structural member 61 to overlap and join the locking portion 615 onto the support structure, thereby stably positioning the first structural member 61 in the locked position where it is locked into the case assembly 1021 and improving the reliability of the locking engagement.

[0172] In some embodiments of the present application, a first positioning structure 10215 is provided on the side of the stopper portion 10211 facing the receiving groove 10213, and a second positioning structure 6151 is provided on the side of the locking portion 615 facing the stopper portion 10211, so that the positioning engagement between the first positioning structure 10215 and the second positioning structure 6151 prevents the locking portion 615 from rotating relative to the stopper portion 10211. Therefore, by providing the first positioning structure 10215 and the second positioning structure 6151, the stability of the locking engagement between the first structural member 61 and the case assembly 1021 is improved, and the risk of the first structural member 61 rotating due to an external force and the locking portion 615 detaching from the stopper portion 10211 and releasing the lock is reduced, thereby increasing the reliability of the locking engagement between the first structural member 61 and the case assembly 1021.

[0173] For example, one of the first positioning structure 10215 and the second positioning structure 6151 is a protrusion structure and the other is a groove structure, and the protrusion structure and the groove structure are fitted together. This makes it possible to simply and effectively achieve positioning and fitting between the first positioning structure 10215 and the second positioning structure 6151, and also makes it easy to process the first positioning structure 10215 and the second positioning structure 6151, resulting in low manufacturing costs.

[0174] 11 and 12, the protrusion structure may include a plurality of strip ribs spaced apart along the rotational direction of the first structural member 61, and the groove structure may include a plurality of strip grooves spaced apart along the rotational direction of the first structural member 61, with the strip ribs fitting into the strip grooves in a one-to-one correspondence. This improves the reliability and stability of the positioning and fitting, and effectively increases the stability of the locking fit between the first structural member 61 and the case assembly 1021.

[0175] 15 and 16, in some other specific examples, the protrusion structure includes a bump structure, the groove structure includes an arc-shaped groove extending along the rotation direction of the first structural member 61, and the bump structure is fitted into the arc-shaped groove. Therefore, since the processing precision can be reduced, it is relatively easy to position and fit the protrusion structure and the groove structure.

[0176] In the embodiments of the present application, the protruding surface of the protruding structure may be a curved surface, which has a relatively good directionality and is less likely to be damaged when entering or exiting the groove structure, thereby protecting the structure, extending its service life, and improving the smoothness of operation.

[0177] Of course, the present application is not limited thereto. The first positioning structure 10215 and the second positioning structure 6151 may be arranged in other forms. For example, one of the first positioning structure 10215 and the second positioning structure 6151 is an expandable positioning pin pressed by a spring, and the other is a pinhole. When the first structural member 61 is rotated to the locking position, the positioning pin enters the pinhole under the action of the spring, thereby achieving locking engagement.

[0178] In the embodiments of the present application, the arrangement of the central portion 614 relative to the flow path 1021A is not limited. For example, the central portion 614 may be disposed on the side of the flow path 1021A away from the receiving cavity 1A. As another example, the central portion 614 may be at least partially fitted within the flow path 1021A. Here, when the central portion 614 is fitted within the flow path 1021A, the central portion 614 and the flow path 1021A may be disposed so as to form a cylindrical engagement. That is, the outer circumferential surface of the central portion 614 is a cylindrical surface, the flow path 1021A has a circular hole, and the central portion 614 is positioned within the circular hole of the flow path 1021A. In this way, when the first structural member 61 rotates, the central portion 614 and the flow path 1021A are not affected by interference, ensuring smooth rotation of the first structural member 61. Furthermore, since the fitting gap 26 between the central portion 614 and the flow path 1021A can be made smaller, the possibility of foreign matter entering through the fitting gap 26 is reduced, which helps to improve the reliability of the battery cell 102.

[0179] In some embodiments of the present application, as shown in FIG. 9 , at least a portion of the second structural member 62 is inserted into the flow channel 1021A and forms an interference fit with the flow channel 1021A to seal the flow channel 1021A. Therefore, the interference fit allows the second structural member 62 to simply and effectively seal the flow channel 1021A, providing a reliable seal while reducing structural complexity and processing difficulty and reducing production costs. The interference fit also makes it easy to remove the second structural member 62 and open the flow channel 1021A. Of course, the present application is not limited thereto. To seal the flow channel 1021A, the second structural member 62 may be disposed to cover a cross section of the flow channel 1021A.

[0180] In some embodiments, when at least a portion of the second structural member 62 is inserted into the flow channel 1021A and tightly fitted into the flow channel 1021A to seal the flow channel 1021A, the first structural member 61 and the second structural member 62 may be arranged to form an insertion fit with cylindrical surfaces. For example, to form the insertion fit with cylindrical surfaces, one of the first structural member 61 and the second structural member 62 may have a cylindrical convex structure and the other may have a cylindrical concave structure, with the convex structure fitting into the concave structure. In this way, the insertion fit with cylindrical surfaces allows the first structural member 61 to rotate relative to the second structural member 62. In other words, when the second structural member 62 is tightly fitted into the flow path 1021A, in the process of rotating the first structural member 61 to lock the first structural member 61, the insertion fit using the cylindrical surface allows the first structural member 61 to rotate alone without rotating together with the second structural member 62, thereby reducing the force required to rotate the first structural member 61 and increasing the smoothness of rotation of the first structural member 61.

[0181] When the convex and concave structures are inserted and fitted by the cylindrical surfaces, the convex and concave structures may be interference fitted to form a connection between the first structural member 61 and the second structural member 62, but it will be understood that since the tightness of the interference fit between the convex and concave structures is less than the tightness of the interference fit between the second structural member 62 and the flow path 1021A, only the first structural member 61 can rotate without rotating together with the second structural member 62.

[0182] In some embodiments of the present application, as shown in FIG. 9 , the flow path 1021A includes a first passage portion A1 and a second passage portion A2 arranged in sequence along the liquid injection direction, with the cross-sectional area of ​​the first passage portion A1 being larger than that of the second passage portion A2. The second structural member 62 is interference-fitted into the second passage portion A2, and at least a portion of the first structural member 61 is fitted into the first passage portion A1. Therefore, providing the first passage portion A1 with a relatively large cross-sectional area fitted into the first structural member 61 is beneficial for the lock design of the first structural member 61 and makes it easier to lock and unlock the first structural member 61. Furthermore, providing the second passage portion A2 with a relatively small cross-sectional area interference-fitted into the second structural member 62 is beneficial for reducing the difficulty of sealing and improving the sealing effect.

[0183] 9 , in the case assembly 1021, a step surface 10216 is formed at the connection portion between the first passage portion A1 and the second passage portion A2, and the second structural member 62 is partially supported on a side of the step surface 10216 away from the accommodating cavity 1A. Illustratively, the case assembly 1021 includes a support portion 10214 including the step surface 10216, and the second structural member 62 includes a lap joint 622 lap-jointed to the outside of the step surface 10216 (i.e., the side away from the accommodating cavity 1A). Therefore, by partially supporting the second structural member 62 on the side of the step surface 10216 away from the accommodating cavity 1A, the sealing effect of the second structural member 62 on the flow path 1021A is enhanced to some extent, and by partially supporting the second structural member 62 on the side of the step surface 10216 away from the accommodating cavity 1A, the second structural member 62 is made easier to remove.

[0184] For example, the second structural member 62 and the first structural member 61 may be separable, and the second structural member 62 can be removed by simply applying force to the portion of the second structural member 62 that is lap-joined to the stepped surface 10216. Naturally, the present application is not limited to this. When the first structural member 61 can be removed together with the second structural member 62, or when the second structural member 62 has a tool-fitting structure, the second structural member 62 may be configured to be completely fitted into the flow path 1021A.

[0185] In some embodiments, the case assembly 1021 has a step surface 10216 formed at the connection between the first passage portion A1 and the second passage portion A2. The step surface 10216 extends obliquely from the hole wall of the first passage portion A1 toward the second passage portion A2, toward the receiving cavity 1A. For example, when the first passage portion A1 is located above the second passage portion A2 and the receiving cavity 1A is located below the second passage portion A2, the step surface 10216 extends at a gradual downward incline from the edge to the center. Therefore, the step surface 10216 has a guiding effect of guiding electrolyte accumulated in the first passage portion A1 to the second passage portion A2, thereby alleviating the problem of electrolyte accumulation in the first passage portion A1 and improving the reliability of the battery cell 102.

[0186] In some embodiments, the step surface 10216 extends obliquely from the hole wall of the first passage portion A1 toward the second passage portion A2, toward the receiving cavity 1A, and the second structural member 62 is partially supported on the side of the step surface 10216 that is away from the receiving cavity 1A. In this case, the local shape of the second structural member 62 can be set to match the shape of the step surface 10216, which helps to increase the stability of the fit between the second structural member 62 and the flow path 1021A and also helps to improve the sealing effect of the second structural member 62 on the flow path 1021A.

[0187] Of course, the present application is not limited thereto. The sealing structure 1022 in the embodiments of the present application does not have to be composed of two parts, the first structural member 61 and the second structural member 62. For example, in some embodiments, the sealing structure 1022 may be an integrated part, i.e., it may be interference-fitted with the flow path 1021A and locked to the case assembly 1021. For example, by integrating the first structural member 61 and the second structural member 62 in the above structural configuration, production costs can be reduced.

[0188] In some embodiments of the present application, the sealing structure 1022 is configured to be at least partially fitted into the flow path 1021A through an inlet of the flow path 1021A. In this manner, it is easy to operate the sealing structure 1022 to open or close the flow path 1021A. For example, if the sealing structure 1022 is removably fitted into the case assembly 1021, it is easy to attach and detach the sealing structure 1022. Furthermore, the sealing structure 1022 is at least partially fitted into the flow path 1021A, i.e., the sealing structure 1022 may be completely fitted into the flow path 1021A, or only a portion of the sealing structure 1022 may be fitted into the flow path 1021A. Therefore, the space within the flow path 1021A can be utilized to the maximum extent, increasing the reliability of sealing the flow path 1021A by the sealing structure 1022, while reducing the height of the sealing structure 1022 protruding outward from the flow path 1021A and reducing the space outside the case assembly 1021 occupied by the sealing structure 1022, which helps to reduce the overall size of the battery cell 102. Naturally, the present application is not limited to this. The sealing structure 1022 may be arranged to completely cover the outside of the flow path 1021A, but this will not be described again here.

[0189] 6, for example, if the flow path 1021A includes a first passage portion A1 and a second passage portion A2 arranged in order along the liquid injection direction in the above embodiment, and the cross-sectional area of ​​the first passage portion A1 is larger than the cross-sectional area of ​​the second passage portion A2, the inlet of the first passage portion A1 can be used as the inlet of the flow path 1021A. In this case, the sealing structure 1022 can extend into the flow path 1021A through the inlet of the first passage portion A1 and be fitted into at least the first passage portion A1. For example, the sealing structure 1022 can be fitted only in the first passage portion A1, or, as another example, the sealing structure 1022 can be partially fitted in the first passage portion A1 and the remaining portion in the second passage portion A2.

[0190] 5 to 7 , in some embodiments of the present application, the case assembly 1021 includes a mounting portion 8, the flow path 1021A includes a liquid injection hole 31 formed in the mounting portion 8, the mounting portion 8 includes a base 81 and a pedestal 82 attached to the base 81, and the sealing structure 1022 is fitted into the pedestal 82 and is configured to open or seal the liquid injection hole 31. Note that the liquid injection hole 31 may be formed only on the base 81, or may be formed on both the base 81 and the pedestal 82 (i.e., a portion of the liquid injection hole 31 is formed on the base 81 and another portion is formed on the pedestal 82), but this is not limited thereto.

[0191] Among these, the base 82 is a separately processed part and is attached to the base 81 through an assembly process. The assembly connection between the base 81 and the base 82 can be achieved by selecting various methods such as, for example, welding, adhesive bonding, interlocking, and interference fit, but is not limited thereto. Therefore, by positioning the base 82 and fitting the sealing structure 1022 to the base 82 (for example, by fitting the two detachably or relatively movably), the base 82 can be processed into a shape suitable for fitting with the sealing structure 1022, thereby reducing the structural complexity of the base 81 and the difficulty of processing the base 81.

[0192] For example, since base 81 and pedestal 82 are made of the same metal material and connected by welding, the reliability of the connection between them can be increased and the sealing performance at the connection position can be improved. In addition, pedestal 82 itself has relatively good structural reliability, and the stability of the fit with sealing structure 1022 is relatively high.

[0193] In some embodiments, as shown in FIG. 17, the base 81 is provided with an attachment groove 811 that opens away from the accommodating cavity 1A, and at least a portion of the pedestal 82 is fitted into this attachment groove 811, thereby improving the assembly efficiency between the pedestal 82 and the base 81 and the stability of the connection between the pedestal 82 and the base 81, and reducing the space outside the base 81 occupied by the pedestal 82.

[0194] For example, in some embodiments, when the sealing structure 1022 is removably fitted to the case assembly 1021, the sealing structure 1022 may be removably fitted to the base 82. For example, when the sealing structure 1022 includes the first structural member 61 in the above embodiments, the first structural member 61 may be configured to be lockably fitted to and unlocked from the base 82. For example, when the stopper portions 10211 and the escape holes 10212 are formed on the case assembly 1021 and are positioned around the flow path 1021A in the above embodiments and arranged alternately, both the stopper portions 10211 and the escape holes 10212 can be machined on the base 82, thereby reducing the difficulty of machining the base 81.

[0195] Furthermore, when the type of base 81 is diverse or uncertain, providing a pedestal 82 that can be fitted to the sealing structure 1022 can improve compatibility and expand usage scenarios. For example, the base 81 may be part of a pressure release structure, part of a pole cover plate, or part of a case. The sealing structure 1022 can be attached by simply drilling holes on the base 81 to meet the attachment requirements of the pedestal 82, without providing related structures (e.g., stopper portions 10211, escape holes 10212, etc.) on the base 81 that are fitted to the sealing structure 1022. This simplifies the design and processing of the base 81.

[0196] For example, in some embodiments, when the liquid injection hole 31 includes a first passage portion A1 and a second passage portion A2 arranged in order along the liquid injection direction in the above embodiments and the cross-sectional area of ​​the first passage portion A1 is larger than the cross-sectional area of ​​the second passage portion A2, the inlet of the first passage portion A1 can be the inlet of the liquid injection hole 31, and the inlet of the liquid injection hole 31 can be the inlet of the flow path 1021A. In this case, the sealing structure 1022 can extend into the flow path 1021A through the inlet of the first passage portion A1 (i.e., the inlet of the liquid injection hole 31). Illustratively, the pedestal 82 defines the first passage portion A1, and the base 81 defines the second passage portion A2. At the same time, when the sealing structure 1022 comprises the above-mentioned first structural member 61 and second structural member 62, the second structural member 62 is tightly fitted into the second passage portion A2 of the base 81, and at least a portion of the first structural member 61 is fitted into the first passage portion A1 of the pedestal 82, thereby realizing locking and unlocking between the first structural member 61 and the pedestal 82.

[0197] In battery cells of the related art, liquid injection holes, electrode posts, and explosion-proof valves are spaced apart on the top cover of the case. Because the liquid injection holes are provided separately on the top cover and occupy an area of ​​the top cover, the area of ​​the electrode posts is reduced. Increasing the area of ​​the electrode posts requires a larger top cover, which increases the size of the top cover and the weight of the larger top cover, making it difficult to achieve a compact and lightweight top cover. Furthermore, because the liquid injection holes must be separately machined on the top cover, the structure of the top cover becomes relatively complex, making processing relatively difficult, and the processing of the liquid injection holes is not easy. Furthermore, for sealing purposes, a sealing pin must be welded onto the top cover to seal the liquid injection hole. However, as the energy density of battery cells increases, the top cover becomes increasingly thinner, which tends to cause the top cover to be crushed or pierced at the location where the sealing pin is welded. To address this issue, the portion of the top cover where the sealing pin is welded is typically thickened, which increases the material and manufacturing costs of the top cover. Alternatively, the entire top cover would need to be thickened, which would not meet the requirements for making the top cover thinner and lighter, thereby affecting the improvement of the energy density of the battery cell. Furthermore, the lower plastic structure below the top cover needs to be thickened to ensure insulation of the sealing pin and avoid interference between the sealing pin and the cell assembly inside the case. A thicker lower plastic structure not only increases material costs but also occupies more space in the receiving cavity, thereby affecting the improvement of the energy density of the battery cell.

[0198] 6 , in some embodiments of the present application, a case assembly 1021 includes a case 1 defining a receiving cavity 1A and a polar pillar structure 1020 provided on the case 1. The polar pillar structure 1020 is a mounting portion 8, a flow path 1021A is provided on the polar pillar structure 1020 (e.g., provided on the mounting portion 8) and includes a liquid injection hole, and a sealing structure 1022 is fitted to the polar pillar structure 1020 (e.g., fitted to the mounting portion 8) and configured to open or seal the liquid injection hole 31. Therefore, by disposing the flow path 1021A available for liquid injection in the mounting portion 8 and using the polar pillar structure 1020 as the mounting portion 8, electrolyte can be injected from the polar pillar structure 1020. This eliminates the need to provide a separate flow path 1021A on the case 1, and the flow path 1021A does not occupy space in the case 1. Furthermore, because there is no need to reduce the size of polar pillar structure 1020 to avoid flow path 1021A, the area of ​​polar pillar structure 1020 can be expanded to increase the liquid passage area of ​​polar pillar structure 1020, provided that the size of case 1 is not increased, which helps to reduce resistance to liquid passage and improve liquid passage efficiency. Increasing the area of ​​polar pillar structure 1020 also helps to assemble and connect polar pillar structure 1020 to case 1. Furthermore, because there is no need to increase the size of case 1 to increase the area of ​​polar pillar structure 1020, it helps to make case 1 more compact and lightweight.

[0199] Furthermore, since special processing is not required on the case 1 to open the flow channel 1021A on the case 1, this helps reduce the structural complexity and difficulty of processing the case 1. Furthermore, since it is not necessary to thicken the case 1 in parts to weld a sealing pin to the case 1, the structure and processing of the case 1 can be further simplified. Furthermore, since it is not necessary to thicken the entire case 1 to weld a sealing pin to the case 1, this satisfies the requirement to make the case 1 thin and lightweight, which helps improve the energy density of the battery cell 102 and reduce the weight and material costs of the case 1. Furthermore, by arranging the flow channel 1021A in the pole structure 1020, the manufacturing and processing of the flow channel 1021A is simplified, and the size, shape, etc. of the flow channel 1021A can more easily meet design and application requirements, which helps reduce the difficulty of processing the flow channel 1021A and the processing costs of the flow channel 1021A.

[0200] 17 and 18, in some embodiments of the present application, the electrode post structure 1020 includes an electrode post body 2 attached to the case 1 and an electrode post cover plate 3 covering the electrode post body 2. The flow path 1021A also includes a communication passage 2A formed on the electrode post body 2 and communicating with the accommodating cavity 1A. A liquid injection hole 31 is formed on the electrode post cover plate 3 and communicates with the communication passage 2A. A sealing structure 1022 is fitted to the electrode post cover plate 3 to open or close the liquid injection hole 31.

[0201] Because the electrode post bar plate 3 is covered by the electrode post body 2, the liquid injection hole 31 is located upstream of the communicating channel 2A in the liquid flow direction. That is, when electrolyte is injected into the battery cell 102, the electrolyte first flows through the liquid injection hole 31 and then through the communicating channel 2A. Therefore, when electrolyte needs to be injected into the accommodating cavity 1A of the battery cell 102, it can be injected into the liquid injection hole 31. Because the liquid injection hole 31 communicates with the communicating channel 2A, the electrolyte that enters the liquid injection hole 31 can flow into the communicating channel 2A, and because the communicating channel 2A communicates with the accommodating cavity 1A, the electrolyte that enters the communicating channel 2A can flow into the accommodating cavity 1A. This enables the injection of liquid into the accommodating cavity 1A via the liquid injection hole 31 and the communicating channel 2A.

[0202] Therefore, the flow path 1021A, which includes the communication path 2A and the liquid injection hole 31, extends the liquid injection path to some extent, providing a buffering effect against liquid injection to some extent and helping to reduce the possibility of electrolyte splashing or overflowing during liquid injection or operation of the battery cell 102. Furthermore, by providing the liquid injection hole 31 in the electrode post cover plate 3, the electrode post cover plate 3 also has the electrode post body 2 on the side adjacent to the receiving cavity 1A. Therefore, even if a sealing pin is disposed in the liquid injection hole 31, the electrode post body is located between the lower plastic structure and the sealing pin. Therefore, the lower plastic structure does not need to be thickened to ensure insulation from the sealing pin, and the lower plastic structure does not need to be thickened to prevent the relatively long sealing pin from interfering with the cell assembly. This helps to reduce the thickness of the lower plastic structure and material costs. Furthermore, the space occupied by the lower plastic structure in the receiving cavity 1A is reduced, helping to improve the energy density of the battery cell 102. Of course, in some embodiments of the present application, the sealing pin may be omitted when the sealing structure 1022 is provided.

[0203] Here, the specific method of fitting the sealing structure 1022 and the cover plate portion 36 is not particularly limited as long as it can open or seal the liquid injection hole 31. For example, in some embodiments, as shown in Figure 17, the pole cover plate 3 includes a cover plate portion 36 that covers the pole body 2 and a first base portion 37 that is attached to the cover plate portion 36, and at least a portion of the liquid injection hole 31 is formed on the first base portion 37, and the sealing structure 1022 is fitted into the first base portion 37.

[0204] Illustratively, the liquid injection hole 31 includes a second passage portion A2 formed on the cover plate portion 36 and a first passage portion A1 formed on the first seat portion 37, and the sealing structure 1022 is fitted to the first seat portion 37. In this embodiment, when the mounting portion 8 includes a base portion 81 and a seat 82 attached to the base 81, and the sealing structure 1022 is fitted to the seat 82 and configured to open or seal the liquid injection hole 31, it will be understood that if the polar column structure 1020 is the mounting portion 8, the cover plate portion 36 will be the base 81 and the first seat portion 37 will be the seat 82.

[0205] For example, when the sealing structure 1022 is removably fitted to the case assembly 1021, the sealing structure 1022 may be removably fitted to the first base portion 37. For example, when the sealing structure 1022 includes the first structural member 61 in the above embodiment, the first structural member 61 may be configured to be lockably fitted to and unlocked from the first base portion 37. For example, when the stopper portions 10211 and the bypass holes 10212 are formed on the case assembly 1021 and are positioned around the flow path 1021A in the above embodiment and arranged alternately, the stopper portions 10211 and the bypass holes 10212 can both be machined on the first base portion 37, thereby reducing the difficulty of machining the cover plate portion 36.

[0206] The method of assembling the cover plate 36 and the first base 37 is not limited, and various methods, such as welding, adhesive bonding, fastening, or interference fit, may be selected. For example, the cover plate 36 and the first base 37 are made of the same metal material and connected by welding, which increases the reliability of the connection between them and improves the sealing performance at the connection position. Furthermore, the structural reliability of the first base 37 itself is relatively high, and the fit with the sealing structure 1022 is relatively stable. Furthermore, when the cover plate 36 and the first base 37 are made of the same material, even if the welded position between the cover plate 36 and the first base 37 comes into contact during the electrolyte injection process, contamination or corrosion is unlikely to occur at that position, thereby ensuring a relatively high reliability of the connection between the cover plate 36 and the first base 37.

[0207] In some embodiments, as shown in FIG. 17, a first mounting groove 361 that opens in a direction away from the accommodating cavity 1A is provided in the cover plate portion 36, and at least a portion of the first base portion 37 is fitted into the first mounting groove 361, thereby improving the assembly efficiency between the first base portion 37 and the cover plate portion 36 and the stability of the connection between the first base portion 37 and the cover plate portion 36, and reducing the space outside the cover plate portion 36 occupied by the first base portion 37.

[0208] 18, the pole cover plate 3 does not have to be divided into two parts, the first base portion 37 and the cover plate portion 36. For example, it may be an aluminum cover plate or a copper-aluminum composite cover plate. The liquid injection hole 31, stopper portion 10211, escape hole 10212, etc. may be directly machined on the pole cover plate 3 without the first base portion 37, and fitted into the sealing structure 1022, thereby omitting the first base portion 37, reducing the number of parts and improving assembly efficiency.

[0209] In some embodiments, as shown in Figures 17 and 18, the communication passage 2A has a first accommodating groove 211 that opens toward the pole cover plate 3 and communicates with the liquid injection hole 31, and a liquid passage hole 23 that penetrates the groove wall of the first accommodating groove 211 and communicates between the first accommodating groove 211 and the accommodating cavity 1A.

[0210] Illustratively, the communication passage 2A includes a first accommodating groove 211 and a liquid passing hole 23. The first accommodating groove 211 opens toward the electrode post cover plate 3 (i.e., the first accommodating groove 211 opens on the side of the first accommodating groove 211 away from the accommodating cavity 1A, or the groove opening of the first accommodating groove 211 is located on the side of the accommodating groove 21 away from the accommodating cavity 1A), so that the first accommodating groove 211 communicates with the liquid injection hole 31, and the liquid passing hole 23 penetrates the groove wall of the first accommodating groove 211 on the side away from the electrode post cover plate 3 (i.e., the liquid passing hole 23 is located on the side of the first accommodating groove 211 close to the accommodating cavity 1A and penetrates the groove wall of the first accommodating groove 211 close to the accommodating cavity 1A), so that the first accommodating groove 211 communicates with the accommodating cavity 1A via the liquid passing hole 23. Alternatively, the liquid passage hole 23 may penetrate the groove wall at another position of the first accommodating groove 211, as long as it can connect the first accommodating groove 211 and the accommodating cavity 1A.

[0211] When electrolyte needs to be injected into the accommodating cavity 1A of the battery cell 102, it can be injected through the liquid injection hole 31. The liquid injection hole 31 is connected to the first accommodating groove 211, allowing the electrolyte that has entered the liquid injection hole 31 to flow into the first accommodating groove 211, and the first accommodating groove 211 is connected to the accommodating cavity 1A through the liquid passing hole 23, allowing the electrolyte that has entered the first accommodating groove 211 to flow into the accommodating cavity 1A through the liquid passing hole 23. This allows the electrolyte to be injected into the accommodating cavity 1A through the liquid injection hole 31, the first accommodating groove 211, and the liquid passing hole 23.

[0212] Therefore, since the communication passage 2A has the first accommodating groove 211 formed on the electrode post body 2, the first accommodating groove 211 can buffer the electrolyte, thereby alleviating problems such as electrolyte splashing or overflowing when the battery cell 102 is filled or operated. Furthermore, since the first accommodating groove 211 can buffer the electrolyte when filling it, it helps to improve the efficiency of filling the electrolyte. Furthermore, the groove sidewall of the first accommodating groove 211 (i.e., the groove wall extending from the open side of the first accommodating groove 211 toward the accommodating cavity 1A) prevents the electrolyte from splashing to some extent, thereby reducing external contamination caused by the electrolyte.

[0213] When the communication passage 2A includes the first accommodating groove 211, the liquid passing hole 23 can be provided on the side of the first accommodating groove 211 that is close to the accommodating cavity 1A, and can penetrate the groove wall of the first accommodating groove 211 that is close to the accommodating cavity 1A. In this case, because the first accommodating groove 211 corresponds to a sunken structure, the liquid passing hole 23 is spaced apart from the groove opening of the first accommodating groove 211 and is relatively far away from the connection between the electrode post cover plate 3 and the electrode post main body 2. Even if the electrolyte overflows from the liquid passing hole 23, the overflowing electrolyte is unlikely to come into contact with the connection position (e.g., welding position or bonding position) between the electrode post cover plate 3 and the electrode post main body 2, thereby reducing corrosion and contamination of the connection position.

[0214] In some embodiments of the present application, the cross-sectional shape of the first accommodating groove 211 is consistent with the cross-sectional shape of the pole body 2. This makes full use of the space of the pole body 2 and maximizes the size of the first accommodating groove 211, which helps the first accommodating groove 211 to more effectively perform its functions of buffering, receiving, etc.

[0215] Of course, the present application is not limited thereto. For example, in some embodiments of the present application, the pole body 2 does not have the first receiving groove 211, but only has the liquid passage hole 23, and the liquid injection hole 31 faces and communicates with the liquid passage hole 23, so as to meet the liquid injection requirements.

[0216] It will be understood that the electrode post cover plate 3 is located outside at least a portion of the electrode post body 2 (i.e., the side away from the receiving cavity 1A) and is covered by the electrode post body 2, so that the liquid injection hole 31 can be located upstream of the communication passage 2A on the electrode post body 2. It should be noted that the method of assembling the electrode post cover plate 3 and the electrode post body 2 is not limited. For example, the electrode post cover plate 3 may be located completely outside the electrode post body 2 (i.e., the side away from the receiving cavity 1A), or the electrode post cover plate 3 may be partially fitted into the electrode post body 2.

[0217] For example, in some embodiments of the present application, as shown in Figures 19 and 20, at least a portion of the electrode post cover plate 3 is fitted into the first accommodating groove 211. Because the first accommodating groove 211 is used as part of the communication passage 2A, a cavity is formed between the electrode post cover plate 3 and the groove wall of the first accommodating groove 211. In this way, the electrode post cover plate 3 occupies the space within the first accommodating groove 211, while ensuring a space within the first accommodating groove 211 for the electrolyte to flow. This allows the electrolyte injected through the liquid injection hole 31 to pass through the cavity and enter the liquid passage hole 23, thereby satisfying the liquid injection requirements and also buffering the electrolyte, thereby alleviating problems such as electrolyte splashing and overflow.

[0218] Furthermore, when the battery cell 102 is in use, the cavity can be used to buffer gas generated within the battery cell 102 or electrolyte overflowing from the receiving cavity 1A, thereby helping to improve the reliability of operation of the battery cell 102. Furthermore, when the battery cell 102 is produced, the cavity can buffer the injected electrolyte, preventing electrolyte overflow and increasing liquid injection efficiency. Furthermore, by fitting at least a portion of the electrode post cover plate 3 into the first receiving groove 211, the space outside the electrode post body 2 occupied by the electrode post cover plate 3 can be reduced, improving the compactness of the structure.

[0219] 19 and 20, in some embodiments of the present application, the edge of the pole cover plate 3 is provided with a lip 32, and the lip 32 is lap-jointed to the side of the pole body 2 away from the receiving cavity 1A. This facilitates fitting and connection between the pole cover plate 3 and the pole body 2, and makes it easy to control the height of the cavity between the pole cover plate 3 and the groove wall of the first receiving groove 211, so that the volume of the cavity meets the design requirements.

[0220] 19 and 20 , when the communication passage 2A includes the first accommodating groove 211, a countersunk groove 25 is provided on the surface of the pole body 2 away from the accommodating cavity 1A, surrounding the first accommodating groove 211. At least a portion of the edge 32 is fitted into the countersunk groove 25 so as to lap-join the edge 32 on the side of the pole body 2 away from the accommodating cavity 1A. Therefore, positioning by the countersunk groove 25 can improve the efficiency of assembling the pole body 2 and the pole cover plate 3. Furthermore, the positional restriction provided by the countersunk groove 25 can improve the stability and reliability of the fit between the pole body 2 and the pole cover plate 3. Furthermore, providing the countersunk groove 25 allows the pole cover plate 3 to be fitted deeper into the pole body 2, reducing or eliminating the portion of the pole cover plate 3 that protrudes into the pole body 2, which helps to reduce the space occupied outside the pole body 2.

[0221] In some embodiments, when the edge 32 is welded to the pole body 2 and the pole body 2 has a liquid passage hole 23, the edge 32 can be separated from the liquid passage hole 23. If the electrolyte overflows from the liquid passage hole 23, the electrolyte can be separated from the welding point between the edge 32 and the pole body 2, thereby improving problems such as corrosion and contamination that occur at the welding point. The welding method between the edge 32 and the pole body 2 is not limited. For example, hot melt welding or brazing may be used. For example, a method of continuously laser welding the edge 32 and the pole body 2 may also be used.

[0222] 19 and 20, a fitting gap 26 is provided between the edge portion 32 and the side wall of the countersunk groove 25, and the dimension W of one end of the fitting gap 26 away from the receiving cavity 1A is less than 0.05 mm, i.e., the fitting gap 26 is greater than 0 mm and less than 0.05 mm. This allows the edge portion 32 of the terminal post cover plate 3 to be smoothly assembled into the countersunk groove 25 of the terminal post body 2, while preventing the fitting gap 26 between them from becoming too large. When the edge portion 32 and the terminal post body 2 are connected by welding, the success rate of welding between the edge portion 32 and the terminal post body 2 can be improved.

[0223] In some embodiments of the present application, the shape of the electrode post cover plate 3 matches the cross-sectional shape of the first accommodating groove 211. Therefore, the electrode post cover plate 3 can be used to cover the first accommodating groove 211. The first accommodating groove 211 can be sealed after the liquid injection hole 31 is sealed, which simplifies the sealing measures for the first accommodating groove 211, reduces the number of parts used, simplifies the structure, facilitates assembly, and reduces costs. Furthermore, because the cross-sectional shape of the edge 32 matches the cross-sectional shape of the countersunk groove 25, the fitting gap 26 between the edge 32 and the side wall of the countersunk groove 25 is uniform.

[0224] 19 and 20 , in some embodiments of the present application, the terminal post body 2 includes an outer stopper portion 271 that is fastened to the outside of the case 1 and has a position restriction, and an inner stopper portion 272 that is fastened to the inside of the case 1 and has a position restriction. The edge portion 32 is overlap-joined onto the outer stopper portion 271, and the terminal post body 2 is riveted to the case 1 to form the outer stopper portion 271. That is, the terminal post body 2 is fixed to the case 1 by riveting, and the outer stopper portion 271 is formed after the terminal post body 2 is riveted. In other words, the outer stopper portion 271 may not be formed on the terminal post body 2 before riveting, but may be formed after riveting. For example, the terminal post body 2 may be first formed by a stamping process, and then the terminal post body 2 may be fixed to the case 1 by riveting.

[0225] Therefore, the outer stopper portion 271 can be easily obtained by simplifying the preparatory processing (for example, a stamping process) before riveting the terminal post body 2. When the structure of the outer stopper portion 271 is relatively complicated, the production cost can be reduced by simplifying the mold (for example, a stamping mold) for preparatory processing of the terminal post body 2. In addition, since the terminal post body 2 riveted to the case 1 may be an integrally molded product, the terminal post body 2 can be reliably connected to the case 1. The stable and reliable connection between the outer stopper portion 271 and the inner stopper portion 272 helps to increase the reliability of the connection between the terminal post body 2 and the terminal post cover plate 3.

[0226] Of course, the present application is not limited thereto. For example, in another embodiment, the inner stopper portion 272 may be processed by riveting. Alternatively, in another embodiment, the pole body 2 may be obtained using a process other than riveting. For example, the pole body 2 may be divided into two parts and fixed onto the case 1 by welding.

[0227] Illustratively, as shown in FIGS. 19 and 20 , the battery cell 102 may also include a seal gasket 1023 (e.g., a seal ring) and an insulating gasket 1024 (e.g., a plastic gasket). The seal gasket 1023 and the insulating gasket 1024 are sandwiched between the pole body 2 and the case 1. The pole body 2 is riveted to the case 1 to fix the seal gasket 1023 and the insulating gasket 1024 between the pole body 2 and the case 1, thereby improving production efficiency and preventing adverse effects of heat on the seal gasket 1023 and the insulating gasket 1024 from the welding process. For example, during riveting, the compression amount of the seal gasket 1023 (i.e., the difference between the thickness of the seal gasket 1023 after deformation and the thickness before deformation divided by the thickness before deformation) may be 15% or more, ensuring sealing performance.

[0228] In some embodiments of the present application, the cathode pole cover plate 3 may be provided with a liquid injection hole 31. Typically, the cathode pole cover plate 3 and the cathode pole body 2 are made of the same material. For example, the cathode pole cover plate 3 needs to be welded to the cathode pole body 2, and the cathode pole cover plate 3 needs to be welded to the current collecting member 103. When the cathode pole cover plate 3 and the cathode pole body 2 are made of the same material, the welding success rate between them is relatively high. When the cathode pole cover plate 3 and the current collecting member 103 are made of the same material, the welding success rate between them is relatively high. Since the cathode pole body 2 and the cathode current collecting member 103 are typically made of aluminum, the cathode pole cover plate 3 may also be made of aluminum. This results in a good welding success rate between the cathode pole cover plate 3 and the cathode pole body 2 and the cathode current collecting member 103. When the liquid injection hole 31 is provided in the cathode pole cover plate 3, the electrolyte flows to the welding point between the cathode pole cover plate 3 and the cathode pole body 2. Because the same material (e.g., aluminum and aluminum) is combined at the welding point, corrosion is less likely to occur at the welding point, which helps to increase the reliability of the connection between the cathode pole cover plate 3 and the cathode pole body 2.

[0229] In some embodiments of the present application, referring to FIG. 21 , the electrode post cover plate 3 includes a first cover plate portion 331 and a second cover plate portion 332. The first cover plate portion 331 and the electrode post body 2 are made of the same material. The first cover plate portion 331 is connected to the electrode post body 2, and the second cover plate portion 332 is connected to the first cover plate portion 331. The liquid injection hole 31 is located on either the first cover plate portion 331 or the second cover plate portion 332. Since the first cover plate portion 331 and the electrode post body 2 are made of the same material, the electrolyte flows to the welding point between the first cover plate portion 331 and the electrode post body 2. The use of the same material at the welding point reduces corrosion at the welding point, which helps to improve the reliability of the connection between the electrode post cover plate 3 and the electrode post body 2. Thus, the liquid injection hole 31 may be located on either the cathode electrode post cover plate 3 or the anode electrode post cover plate 3.

[0230] The method of assembling the first cover plate portion 331 and the second cover plate portion 332 is not limited. For example, orthogonal projection may be performed along the axial direction of the liquid injection hole 31. There may be a portion where the orthogonal projection of the first cover plate portion 331 and the orthogonal projection of the second cover plate portion 332 do not overlap, and the liquid injection hole 31 may be located in that non-overlapping portion. In this way, the welded points between the first cover plate portion 331 and the second cover plate portion 332 will not be corroded or contaminated by the injected electrolyte, which helps to improve the reliability of the electrode post cover plate 3.

[0231] For example, the anode pole body 2 is usually made of copper, and the anode current collecting member 103 is usually made of aluminum. If the anode pole cover plate 3 is made of aluminum, when a liquid injection hole 31 is provided on the anode pole cover plate 3, the electrolyte flows to the welding point between the anode pole cover plate 3 and the anode pole body 2. Because different materials (e.g., aluminum and copper) are combined at the welding point, corrosion is likely to occur at the welding point. Therefore, in some embodiments of the present application, the anode pole cover plate 3 is made of a copper-aluminum composite material, and a first cover plate portion 331 made of copper is welded to the anode pole body 2, and a second cover plate portion 332 made of aluminum is welded to the anode current collecting member 103. This improves the success rate of welding the anode pole cover plate 3 to the anode pole body 2 and the anode current collecting member 103. Thus, when a liquid injection hole 31 is provided on the composite anode pole cover plate 3, it may be provided on the first cover plate portion 331 or the second cover plate portion 332. The electrolyte flows to the welding point between the anode pole cover plate 3 and the anode pole body 2. The same material (for example, copper and copper) is combined at the welding point, which makes the welding point less susceptible to corrosion, and this helps to increase the reliability of the connection between the anode pole cover plate 3 and the anode pole body 2.

[0232] In some embodiments, as shown in FIGS. 18 and 19 , the battery cell 102 further includes a cell assembly 7 including an active material coated portion 71 and a conductive portion 72. The active material coated portion 71 is received in the receiving cavity 1A, and the conductive portion 72 is connected to the active material coated portion 71. Exemplarily, the conductive portion 72 is connected to the electrode post structure 1020 to form an electrical connection and enable the cell assembly 7 to output power from the electrode of the electrode post structure 1020. For example, the conductive portion 72 may be connected to the electrode post structure 1020 by welding or the like. It should be understood that the active material coated portion 71 may include a current collector on which an active material layer is coated. The conductive portion 72 may include only a tab portion, or may include a tab portion and an intermediate connection sheet electrically connected to the tab portion, but this is not limited thereto.

[0233] 18 and 19, a communication hole 22 is formed on the electrode post body 2, connecting the first accommodating groove 211 and the accommodating cavity 1A. There is one or more communication holes 22, and at least one of the communication holes 22 is designated as a liquid passage hole 23. The conductive portion 72 penetrates at least one communication hole 22 and is at least partially received in the first accommodating groove 211. Illustratively, the electrode post body 2 is formed with the first accommodating groove 211 and the communication hole 22. The first accommodating groove 211 opens in a direction away from the accommodating cavity 1A and communicates with the liquid injection hole 31. The communication hole 22 is located on the side of the first accommodating groove 211 that is close to the accommodating cavity 1A, and penetrates the groove wall of the first accommodating groove 211 on the side that is close to the accommodating cavity 1A, connecting the first accommodating groove 211 and the accommodating cavity 1A. At least one communication hole 22 is a liquid passage hole 23. The conductive portion 72 may pass through a communication hole 22 that is designated as a liquid passage hole 23 (i.e., the communication hole 22 through which the conductive portion 72 passes is still usable because the electrolyte passes through it after passing through the conductive portion 72), or may pass through a communication hole 22 that is not designated as a liquid passage hole 23 (i.e., the communication hole 22 through which the conductive portion 72 passes is unusable because the electrolyte passes through it after passing through the conductive portion 72).

[0234] Therefore, by receiving at least a portion of the conductive portion 72 in the first accommodating groove 211 and having at least a portion of the conductive portion 72 occupy the space in the first accommodating groove 211, the space occupied by the conductive portion 72 in the accommodating cavity 1A is reduced, and the space in the accommodating cavity 1A can be saved to receive an active material coating portion 71 with a larger volume, which helps to increase the energy density of the battery cell 102, or helps to reduce the size of the battery cell 102 if the energy density of the battery cell 102 remains unchanged.

[0235] 22 , in some embodiments, the communication hole 22 through which the conductive portion 72 passes is the first communication hole 221 (i.e., the conductive portion 72 passes through at least one communication hole 22, and the communication hole 22 through which the conductive portion 72 passes is the first communication hole 221), and at least the first communication hole 221 may be the liquid passage hole 23. In this way, when the electrode column body 2 has the first communication hole 221 through which the conductive portion 72 passes, the first communication hole 221 through which the conductive portion 72 passes also has a liquid passage function, regardless of whether the electrode column body 2 has second communication holes 222 through which the conductive portion 72 does not pass, as described below. In other words, the first communication hole 221 has a liquid passage gap even after the conductive portion 72 passes through it. When injecting the electrolyte, the electrolyte can be injected into the first storage groove 211 through the liquid injection hole 31, and then at least a portion of the electrolyte can flow into the storage cavity 1A through the first communication hole 221 through which the conductive portion 72 passes.

[0236] 23 , in some embodiments, the communication hole 22 through which the conductive portion 72 passes is the first communication hole 221. There may be a plurality of communication holes 22, and the communication holes 22 may also include at least one second communication hole 222 through which the conductive portion 72 does not pass (i.e., at least one communication hole 22 through which the conductive portion 72 does not pass, and the communication hole 22 through which the conductive portion 72 does not pass is the second communication hole 222), and at least the second communication hole 222 may be the liquid passage hole 23.

[0237] For example, when the first communication hole 221 also has a liquid passage function (i.e., when the first communication hole 221 has a liquid passage gap even after penetrating the conductive portion 72), both the first communication hole 221 and the second communication hole 222 are referred to as liquid passage holes 23. When injecting the electrolyte, after the electrolyte is injected into the first accommodating groove 211 through the liquid injection hole 31, part of the electrolyte may flow into the accommodating cavity 1A through the first communication hole 221 through which the conductive portion 72 has passed, or part of the electrolyte may flow into the accommodating cavity 1A through the second communication hole 222 through which the conductive portion 72 has not passed.

[0238] As another example, if the first communication hole 221 does not have a liquid passage function (i.e., the first communication hole 221 is blocked after penetrating the conductive portion 72, preventing liquid from passing through), only the second communication hole 222 serves as the liquid passage hole 23. When injecting the electrolyte, after the electrolyte is injected into the first accommodating groove 211 through the liquid injection hole 31, some of the electrolyte flows into the accommodating cavity 1A only through the second communication hole 222, which is not penetrated by the conductive portion 72.

[0239] In the examples of the present application, when at least the first communication hole 221 is used as the liquid passage hole 23, the first communication hole 221 also has a liquid passage function, that is, the first communication hole 221 through which the conductive portion 72 passes may be used to allow the electrolyte to pass. In this case, at least the first communication hole 221 may be used to allow the electrolyte to pass. In this way, it is possible to select whether or not to provide a communication hole 22 (for example, the second communication hole 222) through which the conductive portion 72 does not pass, as needed. This reduces the total number of communication holes 22, simplifies the structure and processing of the electrode post body 2, and helps to increase the structural strength of the electrode post body 2.

[0240] In the embodiments of the present application, when at least the second communication hole 222 is used as the liquid passage hole 23, at least the second communication hole 222 may be used for the passage of the electrolyte. In this case, it is not necessary to increase the diameter or number of the first communication holes 221 in order for the electrolyte to pass through them, nor is it necessary to reduce the size of the conductive portion 72 in order for the electrolyte to pass through the first communication holes 221. It is sufficient to design the size of the first communication holes 221 to be slightly larger than the size of the conductive portion 72 so that the conductive portion 72 can pass through. In this way, the problem of impurities and the like falling into the accommodating cavity 1A through the gap between the conductive portion 72 and the first communication hole 221 can be solved, and the problem of localized weakening of the electrode post body 2 due to the first communication hole 221 being too large can also be solved. Furthermore, the size of the conductive portion 72 can be made relatively large, which helps improve current passage efficiency. Furthermore, since the electrolyte is not affected by the conductive portion 72 when passing through the second communication hole 222, the injection efficiency can be improved and the problem of the electrolyte contaminating or corroding the conductive portion 72 is less likely to occur.

[0241] For example, in Example 1 of the present application, there is at least one communication hole 22, and the conductive portion 72 penetrates each communication hole 22, so that each communication hole 22 becomes a first communication hole 221. In this case, at least one first communication hole 221 forms a liquid passage hole 23. After the electrolyte is injected into the first accommodating groove 211 from the liquid injection hole 31, it flows into the accommodating cavity 1A from the first communication hole 221 through which the conductive portion 72 penetrates.

[0242] For example, in Example 2 of the present application, there are at least two communication holes 22, at least one of which is a first communication hole 221 through which the conductive portion 72 passes, and at least one of which is a second communication hole 222 through which the conductive portion 72 does not pass. In this case, the first communication hole 221 and the second communication hole 222 both constitute the liquid passage hole 23. After the electrolyte is injected into the first accommodating groove 211 through the liquid injection hole 31, a portion of the electrolyte flows into the accommodating cavity 1A through the first communication hole 221 through which the conductive portion 72 passes, and the remaining portion flows into the accommodating cavity 1A through the second communication hole 222 through which the conductive portion 72 does not pass.

[0243] For example, in Example 3 of the present application, there are at least two communication holes 22, at least one of which is a first communication hole 221 through which the conductive portion 72 passes, and at least one of which is a second communication hole 222 through which the conductive portion 72 does not pass. The first communication hole 221 is closed after the conductive portion 72 passes through, and liquid cannot pass through. In this case, only the second communication hole 222 constitutes the liquid passage hole 23. After the electrolyte is injected into the first accommodating groove 211 through the liquid injection hole 31, it flows into the accommodating cavity 1A through the second communication hole 222 through which the conductive portion 72 does not pass.

[0244] In some embodiments, the first receiving groove 211 opens in a direction away from the receiving cavity 1A, the groove opening of the first receiving groove 211 is located on the side of the first receiving groove 211 away from the receiving cavity 1A, and the groove wall of the first receiving groove 211 on the side closer to the receiving cavity 1A is the groove bottom wall. The conductive portion 72 is connected to the groove bottom wall to form a first connecting portion 73. The orthogonal projection of the liquid injection hole 31 on the groove bottom wall is offset from the first connecting portion 73, where "offset" in this specification means no overlap.

[0245] For example, if the conductive portion 72 is welded to the bottom wall of the first accommodating groove 211 to form a weld mark, the liquid injection hole 31 may be positioned so that its orthogonal projection onto the bottom wall of the first accommodating groove 211 is misaligned with the weld mark. Therefore, the electrolyte injected from the liquid injection hole 31 avoids the first connection portion 73 (e.g., the weld mark) between the conductive portion 72 and the pole body 2 as much as possible, thereby reducing contamination and corrosion of the first connection portion 73 (e.g., the weld mark) by the electrolyte.

[0246] 22 and 23, in some embodiments, the polar pillar body 2 is formed as an elongated structure, and the first communication hole 221 through which the conductive portion 72 passes is formed as an elongated hole whose length is longer than its width and whose length extends from one end of the polar pillar body 2 to the other end in the longitudinal direction. This makes maximum use of the space in the polar pillar body 2 and allows the length of the first communication hole 221 to be increased as much as possible, allowing a larger conductive portion 72 to pass through the first communication hole 221. This helps increase the size of the conductive portion 72 and improve current passage efficiency. When the first communication hole 221 is used as a liquid passage hole 23, increasing the length of the first communication hole 221 also helps improve injection efficiency.

[0247] 23 and 24 , in some embodiments, when the electrode post body 2 is formed as an elongated structure and the first communication hole 221 through which the conductive portion 72 passes is formed as an elongated hole whose length is longer than its width and whose length extends from one end of the electrode post body 2 to the other end in the longitudinal direction, the electrode post cover plate 3 becomes a long cover plate, i.e., the length of the electrode post cover plate 3 is longer than its width, and the liquid injection hole 31 is provided eccentrically in the longitudinal direction of the electrode post cover plate 3, i.e., the liquid injection hole 31 is located on one side of the center point of the electrode post cover plate 3 in the longitudinal direction. Therefore, the liquid injection hole 31 avoids the conductive portion 72 as much as possible, which can reduce contamination and corrosion of the first connection portion 73 (e.g., weld mark) between the electrode post body 2 and the conductive portion 72 by the injected electrolyte.

[0248] Furthermore, the pole body 2 has an elongated structure, and the pole cover plate 3 is a long cover plate, which helps the pole body 2 to be fully fitted to the pole cover plate 3, making it easier to increase the area of ​​the pole cover plate 3 and facilitating the assembly and connection of the pole cover plate 3 and the pole body 2. For example, the pole cover plate 3 may be cylindrical, rectangular, elliptical, or other shapes. A cylindrical shape formed by connecting semicircles to both ends of a rectangle in the longitudinal direction is also called a runway shape. The liquid injection hole 31 may be located in a semicircular region or in the boundary between the semicircular region and the rectangular region. Of course, this application is not limited to this. In another embodiment of this application, the liquid injection hole 31 may be located in the center of the pole cover plate 3, and the location of the liquid injection hole 31 can be flexibly selected according to actual conditions.

[0249] In some embodiments of the present application, the pole body 2 is formed as an elongated structure, and the first accommodating groove 211 is formed as an elongated groove, that is, the length of the first accommodating groove 211 is longer than the width, and the length of the first accommodating groove 211 extends from one end of the pole body 2 to the other end in the length direction, which facilitates full utilization of the space in the pole body 2, increases the size of the first accommodating groove 211, and helps improve injection efficiency.

[0250] In some embodiments of the present application, the groove wall of the first accommodating groove 211 on the side closest to the accommodating cavity 1A can be arranged as an inclined surface extending downward toward the liquid passage hole 23, which helps the electrolyte in the first accommodating groove 211 to flow quickly toward the liquid passage hole 23, thereby improving the injection efficiency and alleviating the problem of liquid accumulation in the first accommodating groove 211.

[0251] In some embodiments of the present application, the cross-sectional shape of the pole body 2 is set to match the cross-sectional shape of the first accommodating groove 211, thereby making maximum use of space and increasing the size of the first accommodating groove 211 as much as possible, thereby increasing the amount of cushioning provided by the first accommodating groove 211.

[0252] In some embodiments of the present application, when the first receiving groove 211 is formed as an elongated groove, for example, the cross-sectional shape of the first receiving groove 211 can be set to a cylindrical shape, a rectangular shape, an elliptical shape, etc., thereby realizing flexible setting. Among them, a cylindrical shape formed by connecting semicircles to both ends of a rectangle in the longitudinal direction is also called a runway shape.

[0253] In some embodiments, when the communication hole 22 through which the conductive portion 72 passes is a first communication hole 221, there are a plurality of first communication holes 221 and a plurality of conductive portions 72, and at least one conductive portion 72 passes through each first communication hole 221. In this case, since the conductive portions 72 pass through at least two communication holes 22, the size of a single first communication hole 221 becomes relatively large, which alleviates the problem of locally weakening the strength of the pole body 2. Furthermore, when the first communication holes 221 are used as liquid passage holes 23, increasing the number of first communication holes 221 also helps to improve injection efficiency.

[0254] For example, when the first communication hole 221 is formed as an elongated hole whose length is longer than its width and whose length extends from one end of the polar pillar body 2 to the other end in the longitudinal direction, the multiple first communication holes 221 may be arranged at intervals along the width direction of the polar pillar body 2. In this way, the space on the polar pillar body 2 can be utilized to the maximum extent, and the problem of a single first communication hole 221 becoming relatively large and locally weakening the strength of the polar pillar body 2 can be alleviated. Furthermore, when the first communication holes 221 are used as liquid passage holes 23, increasing the number of first communication holes 221 also helps to improve injection efficiency.

[0255] 23 , in some embodiments, when the electrode post body 2 has both the first communication hole 221 and the second communication hole 222, if the first communication hole 221 is formed as an elongated hole whose length is longer than its width and whose length extends from one end of the electrode post body 2 to the other, the second communication hole 222 can be disposed at at least one of the longitudinal ends of the first communication hole 221, so that the electrolyte is relatively far from the weld mark between the conductive portion 72 and the electrode post body 2, thereby reducing contamination or corrosion of the weld mark by the injected electrolyte. Furthermore, if the second communication hole 222 is provided at both longitudinal ends of the first communication hole 221, injection efficiency can be improved and the size of the second communication hole 222 can be reduced, thereby alleviating the problem of localized weakening of the electrode post body 2.

[0256] Of course, in the embodiments of the present application, the shape of the first communicating hole 221 and the relative positional relationship between the first communicating hole 221 and the second communicating hole 222 are not limited to the above description and may be adjusted according to actual conditions.

[0257] Of course, the present application is not limited thereto. In another embodiment of the present application, the conductive portion 72 may not penetrate the communication hole 22 and may not extend into the first accommodating groove 211. In this case, as shown in FIG. 25 , the conductive portion 72 may be connected to the side wall of the electrode post body 2 facing the accommodating cavity 1A so that the entire conductive portion 72 is located on the side of the first accommodating groove 211 that is closest to the accommodating cavity 1A. In this case, each communication hole 22 can be used as a liquid passage hole 23. Therefore, when the electrolyte injected through the liquid injection hole 31 enters the first accommodating groove 211, it does not come into contact with the first connection portion 73 (e.g., a weld mark) between the electrode post body 2 and the conductive portion 72. This reduces contamination and corrosion of the first connection portion 73 between the electrode post body 2 and the conductive portion 72 by the injected electrolyte. Furthermore, it is not necessary to select the position of the liquid injection hole 31 to avoid the first connection portion 73 between the electrode post body 2 and the conductive portion 72, and the position of the liquid injection hole 31 can be flexibly selected.

[0258] 25 , the communication passage 2A also includes a second accommodating groove 212 located on the side of the first accommodating groove 211 closest to the accommodating cavity 1A. The second accommodating groove 212 opens toward the accommodating cavity 1A and communicates with the accommodating cavity 1A. The pole body 2 is formed with a communication hole 22 that connects the first accommodating groove 211 and the second accommodating groove 212, and there is one or more communication holes 22, with at least one communication hole 22 serving as a liquid passage hole 23. In this way, the liquid passage hole 23 penetrates the groove wall of the second accommodating groove 212, connecting the first accommodating groove 211 and the second accommodating groove 212.

[0259] When electrolyte needs to be injected into the accommodating cavity 1A of the battery cell 102, it can be injected through the liquid injection hole 31. Because the liquid injection hole 31 is connected to the first accommodating groove 211, the electrolyte that enters through the liquid injection hole 31 can flow into the first accommodating groove 211. Furthermore, because the first accommodating groove 211 is connected to the second accommodating groove 212 via the communication holes 22, and at least one of the communication holes 22 is a liquid passing hole 23 through which the electrolyte can pass, the electrolyte that enters the first accommodating groove 211 can flow into the second accommodating groove 212 through the liquid passing hole 23. Furthermore, because the second accommodating groove 212 is connected to the accommodating cavity 1A, the electrolyte that enters the second accommodating groove 212 can flow into the accommodating cavity 1A. This allows the electrolyte to be injected into the accommodating cavity 1A via the liquid injection hole 31, the first accommodating groove 211, the liquid passing hole 23, and the second accommodating groove 212.

[0260] Therefore, the second accommodating groove 212 can function to buffer the electrolyte or gas. When the electrolyte is injected into the battery cell 102, the second accommodating groove 212 is used to buffer the electrolyte, thereby preventing problems such as electrolyte splashing and overflow. When the battery cell 102 is operating, the electrolyte generates gas after participating in a reaction. The second accommodating groove 212 can buffer the gas generated in the electrolyte or the accommodating cavity 1A, thereby preventing electrolyte overflow and excessive gas pressure in the accommodating cavity 1A and improving the reliability of the battery cell 102.

[0261] In some embodiments, as shown in FIG. 19 , when a second accommodating groove 212 is provided on the pole body 2, the conductive portion 72 can extend into the first accommodating groove 211 by passing through at least one communication hole 22. When the hole through which the conductive portion 72 passes is the first communication hole 221, the first communication hole 221 may or may not be the liquid passage hole 23. Furthermore, the communication hole 22 connecting the first accommodating groove 211 and the second accommodating groove 212 may also be configured to include at least one second communication hole 222 that is not passed through by the conductive portion 72. The second communication hole 222 may be the liquid passage hole 23. For the above content, please refer to the above description of the embodiment without the second accommodating groove 212, and therefore will not be repeated here.

[0262] For example, when the second accommodating groove 212 is provided on the electrode post body 2, as shown in FIG. 25 , the conductive portion 72 may be entirely located on the side of the first accommodating groove 211 closest to the accommodating cavity 1A without passing through the communicating hole 22. For example, the conductive portion 72 may be connected to the side wall of the electrode post body 2 facing the accommodating cavity 1A, thereby connecting the conductive portion 72 to the groove wall of the second accommodating groove 212 on the side away from the accommodating cavity 1A (e.g., the upper wall of the second accommodating groove 212). In this case, since at least a portion of the conductive portion 72 is received in the second accommodating groove 212, the space occupied by the conductive portion 72 in the accommodating cavity 1A is reduced, saving space within the accommodating cavity 1A and allowing a larger volume of the active material coated portion 71 to be received, which helps to improve the energy density of the battery cell 102. Alternatively, if the energy density of the battery cell 102 remains unchanged, this helps to reduce the size of the battery cell 102.

[0263] 25 , when a second accommodating groove 212 is provided on the electrode post body 2 and the conductive portion 72 is connected to the wall surface of the electrode post body 2 facing the accommodating cavity 1A, each communication hole 22 may be formed as a liquid passing hole 23. Therefore, when the electrolyte injected from the liquid injection hole 31 enters the first accommodating groove 211, it does not come into contact with the first connection portion 73 (e.g., a weld mark) between the electrode post body 2 and the conductive portion 72 in the second accommodating groove 212, which reduces contamination and corrosion of the first connection portion 73 between the electrode post body 2 and the conductive portion 72 by the injected electrolyte. Therefore, it is not necessary to select the position of the liquid injection hole 31 to avoid the first connection portion 73 between the electrode post body 2 and the conductive portion 72, and the position of the liquid injection hole 31 can be flexibly selected.

[0264] In some embodiments of the present application, the liquid injection hole 31 is located on the opposite side of the liquid passage hole 23. In other words, when the liquid injection hole 31 is orthogonally projected along its axial direction, the orthogonal projection of the liquid passage hole 23 at least partially overlaps with the orthogonal projection of the liquid injection hole 31. Therefore, the electrolyte injected through the liquid injection hole 31 can flow directly toward the liquid passage hole 23 opposite the liquid injection hole 31, thereby achieving faster and more efficient injection and improving injection efficiency. The number of liquid injection holes 31 and liquid passage holes 23 is not limited. There may be at least one liquid injection hole 31 and at least one liquid passage hole 23. It is sufficient that the at least one liquid injection hole 31 and at least one liquid passage hole 23 are positioned opposite each other. The shapes of the liquid injection hole 31 and the liquid passage hole 23 may be the same or different, and either shape can be flexibly selected according to actual conditions.

[0265] For example, when the communication hole 22 does not include the second communication hole 222 and includes only the first communication hole 221, the first communication hole 221 is defined as the liquid passage hole 23. In this case, the liquid injection hole 31 may be disposed opposite the first communication hole 221. That is, when orthogonally projected along the axial direction of the liquid injection hole 31, the orthogonal projection of the first communication hole 221 at least partially overlaps with the orthogonal projection of the liquid injection hole 31. Therefore, the electrolyte injected from the liquid injection hole 31 can flow directly toward the first communication hole 221 disposed opposite the liquid injection hole 31, thereby realizing fast and efficient injection and improving injection efficiency.

[0266] For example, when the electrode pillar body 2 has both the first communication hole 221 and the second communication hole 222 and at least the second communication hole 222 is used as the liquid passage hole 23, the second communication hole 222 may be disposed opposite the liquid injection hole 31. That is, when orthogonally projected along the axial direction of the liquid injection hole 31, the orthogonal projection of the second communication hole 222 at least partially overlaps with the orthogonal projection of the liquid injection hole 31. Therefore, the electrolyte injected from the liquid injection hole 31 can flow directly toward the second communication hole 222 disposed opposite the liquid injection hole 31, thereby realizing fast and efficient injection and improving injection efficiency.

[0267] Furthermore, the first communication hole 221 and the liquid injection hole 31 may be positioned offset from each other. That is, when orthogonal projection is performed along the axial direction of the liquid injection hole 31, the orthogonal projection of the first communication hole 221 does not overlap with the orthogonal projection of the liquid injection hole 31. In this way, the electrolyte injected from the liquid injection hole 31 can avoid flowing in the direction of the first communication hole 221, thereby reducing the risk of the electrolyte contaminating the first connection portion 73 between the conductive portion 72 passing through the first communication hole 221 and the electrode post body 2. However, this is not limited to this. In some embodiments of the present application, the liquid injection hole 31 may be positioned to face both the second communication hole 222 and the first communication hole 221, as necessary.

[0268] Furthermore, when the conductive portion 72 is connected to the side wall of the electrode post body 2 facing the accommodating cavity 1A (regardless of whether the communicating passage 2A includes the second accommodating groove 212), each communicating hole 22 can be used as a liquid passage hole 23. In some embodiments, the liquid injection hole 31 may be arranged opposite at least one communicating hole 22, and each communicating hole 22 may be arranged offset from a first connection portion 73 (e.g., a welding mark) between the conductive portion 72 and the electrode post body 2. In other words, when the liquid injection hole 31 is orthogonally projected along the axial direction, the orthogonal projection of each communicating hole 22 does not overlap with the orthogonal projection of the first connection portion 73, which reduces contamination and corrosion of the welding mark by the electrolyte, provided that injection efficiency is improved.

[0269] The embodiments of the present application are not limited to those in which the liquid injection hole 31 is provided on the electrode post cover plate 3. For example, in some other embodiments of the present application, the liquid injection hole 31 may be provided on the electrode post main body 2. For example, referring to FIG. 26 , an electrode post structure 1020 includes an electrode post main body 2 attached to a case 1. The flow path 1021A also includes an accommodating groove 21. Both the accommodating groove 21 and the liquid injection hole are formed on the electrode post main body 2. The liquid injection hole 31 penetrates the groove wall of the accommodating groove 21 on the side away from the groove opening of the accommodating groove 21 (for example, the groove opening of the accommodating groove 21 opens upward, and the liquid injection hole 31 penetrates the bottom wall of the accommodating groove 21. As another example, the groove opening of the accommodating groove 21 opens downward, and the liquid injection hole 31 penetrates the top wall of the accommodating groove 21). As a result, the liquid injection hole 31 communicates with the receiving groove 21 , and the sealing structure 1022 is fitted into the pole body 2 so as to open or seal the liquid injection hole 31 .

[0270] The opening direction of the groove opening of the accommodation groove 21 is not limited. For example, if the groove opening of the accommodation groove 21 opens outward (i.e., in a direction away from the accommodation cavity 1A), the accommodation groove 21 can communicate with the outside of the case 1. In this case, the liquid injection hole 31 can penetrate the groove wall on the side close to the inside of the accommodation groove 21 (i.e., close to the accommodation cavity 1A) to communicate with the inside of the case 1. Therefore, the accommodation groove 21 communicates with the upstream side of the liquid injection hole 31, and the electrolyte can be first injected into the accommodation groove 21 and then flow into the accommodation cavity 1A through the liquid injection hole 31. As another example, if the groove opening of the accommodation groove 21 opens inward (i.e., in a direction close to the accommodation cavity 1A), the accommodation groove 21 can communicate with the inside of the case 1. In this case, the liquid injection hole 31 can penetrate the groove wall on the side close to the outside of the accommodation groove 21 (i.e., close to the accommodation cavity 1A) to communicate with the outside of the case 1. Therefore, the liquid injection hole 31 communicates with the upstream of the receiving groove 21, and the electrolyte can be first injected into the liquid injection hole 31, then enter the receiving groove 21, and then flow into the receiving cavity 1A.

[0271] Therefore, by arranging the liquid injection hole 31 on the pole body 2, it is possible to omit the pole cover plate 3 or the liquid injection hole 31 opened on the pole cover plate 3, thereby simplifying the structure and processing. Furthermore, since the pole body 2 is provided with the receiving groove 21 communicating with the liquid injection hole 31, the liquid injection requirements are met and at the same time, a relatively large buffer space is provided on the pole body 2, which can serve to buffer the electrolyte to a certain extent. This helps to reduce the possibility of electrolyte splashing or spilling during the manufacture or use of the battery cell 102.

[0272] In some embodiments, as shown in FIG. 27 , the pole body 2 comprises a main body portion 28 attached to the case 1 and a second base portion 29 attached to the main body portion 28, at least a portion of the liquid injection hole 31 is formed on the second base portion 29, and the sealing structure 1022 is fitted to the second base portion 29.

[0273] In this embodiment, when the mounting portion 8 comprises a base 81 and a seat 82 attached to the base 81, and the sealing structure 1022 is fitted to the seat 82 and configured to open or seal the liquid injection hole 31, it will be understood that when the pole column structure 1020 is the mounting portion 8, the main body portion 28 is the base 81 and the second seat portion 29 is the seat 82.

[0274] For example, when the sealing structure 1022 is removably fitted to the case assembly 1021, the sealing structure 1022 may be removably fitted to the second base portion 29. For example, when the sealing structure 1022 includes the first structural member 61 in the above embodiment, the first structural member 61 may be configured to be lock-fitted to the second base portion 29 and then unlocked. For example, when the stopper portions 10211 and the escape holes 10212 are formed on the case assembly 1021 and positioned around the flow path 1021A in the above embodiment and arranged alternately, the stopper portions 10211 and the escape holes 10212 can be machined on the second base portion 29, thereby reducing the difficulty of machining the main body portion 28. For example, in some embodiments, the main body portion 28 may include an outer stopper portion 271 that is fastened to the outside of the case 1 in the above embodiment and has a limited position, and an inner stopper portion 272 that is fastened to the inside of the case 1 and has a limited position, etc.

[0275] The method of assembling the main body portion 28 and the second pedestal portion 29 is not limited, and various methods may be selected, such as welding, adhesive bonding, fastening, or interference fit. For example, the main body portion 28 and the second pedestal portion 29 are made of the same metal material and are connected by welding, which increases the reliability of the connection between them and improves the sealing performance at the connection position. Furthermore, the structural reliability of the second pedestal portion 29 itself is relatively high, and the fit with the sealing structure 1022 is relatively stable. Furthermore, when the main body portion 28 and the second pedestal portion 29 are made of the same material, even if the welded position between the main body portion 28 and the second pedestal portion 29 comes into contact during the electrolyte injection process, contamination or corrosion is unlikely to occur at that position, and the reliability of the connection between the main body portion 28 and the second pedestal portion 29 can be relatively well guaranteed.

[0276] In some embodiments, a second mounting groove that opens away from the accommodating cavity 1A is provided on the main body portion 28, and at least a portion of the second base portion 29 is fitted into the second mounting groove, thereby improving the assembly efficiency between the second base portion 29 and the main body portion 28 and the stability of the connection between the second base portion 29 and the main body portion 28, and reducing the space outside the main body portion 28 occupied by the second base portion 29.

[0277] For example, the pole body 2 does not have to be divided into two parts, the second base portion 29 and the body portion 28. In this case, the liquid injection hole 31, the stopper portion 10211, the escape hole 10212, etc. can be directly processed on the pole body 2 that does not have the second base portion 29, and fitted into the sealing structure 1022, thereby omitting the second base portion 29, reducing the number of parts and improving assembly efficiency.

[0278] 27 , in some embodiments of the present application, the accommodating groove 21 includes a third accommodating groove 213 whose groove opening faces away from the accommodating cavity 1A, and the liquid injection hole 31 penetrates the groove wall of the third accommodating groove 213 on the side closer to the accommodating cavity 1A. In this way, when injecting an electrolyte into the battery cell 102, the electrolyte is first injected into the third accommodating groove 213 through the groove opening of the third accommodating groove 213, and the electrolyte that has flowed into the third accommodating groove 213 flows through the liquid injection hole 31 toward the accommodating cavity 1A.

[0279] Therefore, the third receiving groove 213 serves to buffer the electrolyte, thereby alleviating problems such as electrolyte splashing and overflow. Furthermore, the sidewalls of the third receiving groove 213 (groove walls extending in the direction from the groove opening of the third receiving groove 213 toward the receiving cavity 1A) can prevent electrolyte splashing to some extent, reduce external contamination of the electrolyte, and facilitate rapid injection. Furthermore, the liquid injection nozzle can be flexibly positioned. For example, the outlet of the liquid injection nozzle can be enlarged by aligning the outlet with the groove opening of the third receiving groove 213, which further improves injection efficiency. Alternatively, in some optional embodiments, the injection nozzle may be directly aligned with the liquid injection hole 31 to inject the electrolyte, but this is not a limitation.

[0280] In some embodiments of the present application, as shown in FIG. 27 , the accommodating groove 21 further includes a fourth accommodating groove 214 whose groove opening faces the accommodating cavity 1A. The fourth accommodating groove 214 is located on the side of the third accommodating groove 213 closest to the accommodating cavity 1A. The liquid injection hole 31 penetrates the groove wall of the fourth accommodating groove 214 on the side away from the accommodating cavity 1A, connecting the third accommodating groove 213 and the fourth accommodating groove 214. In this manner, when an electrolyte solution is injected into the battery cell 102, the electrolyte solution is first injected into the third accommodating groove 213 through the groove opening of the third accommodating groove 213. The electrolyte solution that has flowed into the third accommodating groove 213 then passes through the liquid injection hole 31 into the fourth accommodating groove 214 and then flows through the opening of the fourth accommodating groove 214 toward the accommodating cavity 1A.

[0281] Therefore, by providing the fourth accommodating groove 214, the height of the liquid injection hole 31 can be increased when injecting the electrolyte, thereby increasing the total amount of injected electrolyte and helping to extend the cycle life of the battery cell 102. Furthermore, because the sealing structure 1022 provided in the liquid injection hole 31 is unlikely to interfere with or be electrically connected to the cell assembly 7 below the electrode post body 2, the lower plastic structure below the electrode post body 2 does not need to be thick, which helps to reduce material costs by making the lower plastic structure thinner. Furthermore, the space within the accommodating cavity 1A occupied by the lower plastic structure is reduced, which helps to improve the energy density of the battery cell 102. Furthermore, when gas generated within the accommodating cavity 1A or electrolyte attempting to overflow may flow into the fourth accommodating groove 214, the fourth accommodating groove 214 acts as a buffer to improve the reliability of operation of the battery cell 102.

[0282] In some embodiments of the present application, the cross-sectional shape of the third accommodating groove 213 and / or the fourth accommodating groove 214 is consistent with the cross-sectional shape of the pole body 2. This makes full use of the space of the pole body 2 and maximizes the size of the third accommodating groove 213 and / or the fourth accommodating groove 214, which helps the third accommodating groove 213 and / or the fourth accommodating groove 214 to more effectively perform their functions of buffering, receiving, etc.

[0283] In some embodiments of the present application, the battery cell 102 includes a cell assembly 7 including an active material coated portion 71 received in the receiving cavity 1A and a conductive portion 72 connected to the active material coated portion 71. Illustratively, the conductive portion 72 is connected to the electrode post body 2 to form an electrical connection and enable the cell assembly 7 to output power from the electrode of the electrode post body 2. For example, the conductive portion 72 may be connected to the electrode post body 2 by welding or the like. Naturally, the active material coated portion 71 may include a current collector coated with an active material layer. The conductive portion 72 may include only a tab portion, or may include a tab portion and an intermediate connection sheet electrically connected to the tab portion, but this is not limited thereto.

[0284] In some embodiments, as shown in FIG. 28 , a communication hole 22 is formed on the electrode post body 2, connecting the third accommodating groove 213 and the accommodating cavity 1A. There is one or more communication holes 22, and at least one of the communication holes 22 is designated as a liquid injection hole 31. A conductive portion 72 penetrates at least one communication hole 22 and is at least partially received in the third accommodating groove 213. Here, the conductive portion 72 may penetrate a communication hole 22 designated as a liquid injection hole 31 (i.e., the communication hole 22 through which the conductive portion 72 penetrates remains usable for the passage of electrolyte after penetrating the conductive portion 72), or may penetrate a communication hole 22 that is not designated as a liquid injection hole 31 (i.e., the communication hole 22 through which the conductive portion 72 penetrates is unusable for the passage of electrolyte after penetrating the conductive portion 72).

[0285] Therefore, by receiving at least a portion of the conductive portion 72 in the third accommodating groove 213 and having at least a portion of the conductive portion 72 occupy the space in the third accommodating groove 213, the space occupied by the conductive portion 72 in the accommodating cavity 1A is reduced, and the space in the accommodating cavity 1A can be saved to receive an active material coating portion 71 with a larger volume, which helps to increase the energy density of the battery cell 102, or helps to reduce the size of the battery cell 102 if the energy density of the battery cell 102 remains unchanged.

[0286] 28 , in some embodiments, the communication hole 22 through which the conductive portion 72 passes is the first communication hole 221 (i.e., the conductive portion 72 passes through at least one communication hole 22, and the communication hole 22 through which the conductive portion 72 passes is the first communication hole 221), and at least the first communication hole 221 may be the liquid injection hole 31. In this way, when the electrode post body 2 has the first communication hole 221 through which the conductive portion 72 passes, the first communication hole 221 through which the conductive portion 72 passes also has a liquid passage function, regardless of whether the electrode post body 2 has a second communication hole 222 through which the conductive portion 72 does not pass, as described below. In other words, the first communication hole 221 has a liquid passage gap even after the conductive portion 72 passes through it. When injecting the electrolyte, after the electrolyte is injected into the third accommodating groove 213, at least a portion of the electrolyte can flow into the accommodating cavity 1A through the first communication holes 221 through which the conductive portion 72 penetrates. At this time, at least the first communication holes 221 may be used for the passage of the electrolyte. In this way, it is possible to select whether or not to provide communication holes 22 (for example, second communication holes 222) that are not penetrated by the conductive portion 72 as needed, which reduces the total number of communication holes 22, simplifies the structure and processing of the electrode post main body 2, and helps to increase the structural strength of the electrode post main body 2.

[0287] 29 , in some embodiments, the communication hole 22 through which the conductive portion 72 passes is the first communication hole 221. There may be a plurality of communication holes 22, including at least one second communication hole 222 through which the conductive portion 72 does not pass (i.e., at least one communication hole 22 through which the conductive portion 72 does not pass is the second communication hole 222), and at least the second communication hole 222 may be the liquid injection hole 31. In this case, there is no need to increase the diameter or number of the first communication holes 221 in order for the electrolyte to pass through the first communication holes 221, nor is there any need to reduce the size of the conductive portion 72 in order for the electrolyte to pass through the first communication holes 221. It is sufficient to design the size of the first communication holes 221 to be slightly larger than the size of the conductive portion 72 so that the conductive portion 72 can pass through. In this way, the problem of impurities and the like falling into the accommodating cavity 1A through the gap between the conductive portion 72 and the first communicating hole 221 can be alleviated, and the problem of localized weakening of the strength of the electrode post body 2 due to an excessively large first communicating hole 221 can also be alleviated. Furthermore, the size of the conductive portion 72 can be made relatively large, which helps improve current passing efficiency. Furthermore, since the electrolyte is not affected by the conductive portion 72 when passing through the second communicating hole 222, injection efficiency can be improved and the problem of the electrolyte contaminating or corroding the conductive portion 72 is less likely to occur.

[0288] 27, the conductive portion 72 may not penetrate the communicating hole 22 and may not extend into the third accommodating groove 213. In this case, the conductive portion 72 may be connected to the side wall of the electrode post body 2 facing the accommodating cavity 1A so that the entire conductive portion 72 is located on the side of the third accommodating groove 213 that is close to the accommodating cavity 1A. In this case, each communicating hole 22 can be used as a liquid injection hole 31. Therefore, when the electrolyte enters the third accommodating groove 213, it does not come into contact with the connection portion (e.g., weld marks) between the electrode post body 2 and the conductive portion 72. This reduces contamination and corrosion of the connection portion between the electrode post body 2 and the conductive portion 72 by the injected electrolyte.

[0289] For example, when the fourth accommodating groove 214 is provided on the electrode post body 2, as shown in FIG. 27 , the conductive portion 72 may be entirely located on the side of the third accommodating groove 213 closest to the accommodating cavity 1A without passing through the communication hole 22. For example, the conductive portion 72 may be connected to the side wall of the electrode post body 2 facing the accommodating cavity 1A, thereby connecting the conductive portion 72 to the groove wall of the fourth accommodating groove 214 on the side away from the accommodating cavity 1A (e.g., the top wall of the fourth accommodating groove 214). In this case, since at least a portion of the conductive portion 72 is received in the fourth accommodating groove 214, the space occupied by the conductive portion 72 in the accommodating cavity 1A is reduced, saving space within the accommodating cavity 1A and allowing a larger volume of the active material coated portion 71 to be received, which helps to improve the energy density of the battery cell 102. Alternatively, if the energy density of the battery cell 102 remains unchanged, this helps to reduce the size of the battery cell 102.

[0290] Furthermore, when a fourth accommodating groove 214 is provided on the electrode post body 2 and the conductive portion 72 is connected to the wall surface of the electrode post body 2 facing the accommodating cavity 1A, each communication hole 22 may be a liquid injection hole 31. Therefore, when the electrolyte flows into the third accommodating groove 213, it does not come into contact with the connection portion (e.g., weld marks) between the conductive portion 72 and the electrode post body 2 in the fourth accommodating groove 214, and therefore contamination and corrosion of the connection portion between the conductive portion 72 and the electrode post body 2 by the injected electrolyte can be reduced.

[0291] In some embodiments, as shown in FIG. 30 , the electrode post structure 1020 further includes a electrode post cover plate 3 that covers the electrode post body 2 and seals the opening of the third accommodating groove 213. After the electrolyte is poured into the electrode post body 2, the electrode post cover plate 3 covers the electrode post body 2 and seals the opening of the third accommodating groove 213 on the electrode post body 2. This seals the third accommodating groove 213, preventing electrolyte overflow and preventing external foreign matter from entering the battery cell 102, thereby improving the reliability of the battery cell 102. The electrode post cover plate 3 is a holeless cover plate, ensuring reliable sealing. The material of the electrode post cover plate 3 is not limited, and it may be a single-material component, such as an aluminum cover plate, or a composite-material component, such as a copper-aluminum composite cover plate; however, this will not be repeated here.

[0292] Furthermore, because liquid injection hole 31 penetrates the groove wall of third accommodating groove 213 on the side closer to accommodating cavity 1A, third accommodating groove 213 has a sunken structure, and liquid injection hole 31 is spaced apart from the groove opening of third accommodating groove 213 and is relatively far away from the connection between electrode post cover plate 3 and electrode post main body 2. Even if electrolyte overflows from liquid injection hole 31, the overflowing electrolyte is unlikely to come into contact with the connection position (e.g., welding position or adhesive position) between electrode post main body 2 and electrode post cover plate 3, thereby reducing corrosion and contamination of the connection position.

[0293] In some embodiments of the present application, the pole body 2 may not have the third accommodating groove 213. For example, referring to Fig. 26, the accommodating groove 21 may include a fifth accommodating groove 215 whose groove opening faces the accommodating cavity 1A, and the liquid injection hole 31 may penetrate the groove wall of the fifth accommodating groove 215 on the side away from the accommodating cavity 1A. In this way, when electrolyte is injected into the battery cell 102, the electrolyte enters the fifth accommodating groove 215 through the liquid injection hole 31 and flows toward the accommodating cavity 1A via the groove opening of the fifth accommodating groove 215.

[0294] Therefore, the fifth accommodating groove 215 can serve to buffer the electrolyte, and the sidewalls of the fifth accommodating groove 215 can prevent the electrolyte from splashing and facilitate rapid injection. Furthermore, the height of the liquid injection hole 31 can be increased. If the liquid injection hole 31 is blocked, gas or electrolyte generated in the accommodating cavity 1A may flow into the fifth accommodating groove 215. The fifth accommodating groove 215 acts as a buffer, improving the reliability of the operation of the battery cell 102. Furthermore, because the height of the liquid injection hole 31 is relatively high, the sealing structure 1022 disposed therein is unlikely to interfere with or be electrically connected to the cell assembly 7 below the pole body 2. This eliminates the need to thicken the lower plastic structure below the pole body 2, thereby reducing material costs. Furthermore, this reduces the space occupied by the lower plastic structure within the accommodating cavity 1A, helping to improve the energy density of the battery cell 102.

[0295] Note that, since the mounting portion 8 according to the embodiments of the present application is not limited to the polar pillar structure 1020, the liquid injection hole 31 is not limited to being formed only on the polar pillar structure 1020. For example, in some embodiments, as shown in FIG. 31 , a case assembly 1021 includes a case 1 defining a receiving cavity 1A and a pressure release structure 1025 provided on the case 1. The pressure release structure 1025 and / or the connection between the pressure release structure 1025 and the case 1 has a weakened area, the pressure release structure 1025 is the mounting portion 8, and the flow path 1021A is provided in the pressure release structure 1025 (e.g., provided in the mounting portion 8) and includes the liquid injection hole 31. The sealing structure 1022 is fitted to the pressure release structure 1025 (e.g., fitted to the mounting portion 8) and configured to open or seal the liquid injection hole 31.

[0296] For example, the fragile portion may be a thin-walled region or a notch. When the pressure in the accommodating cavity 1A exceeds a threshold, the fragile portion is preferentially punched out, and the case 1 releases the pressure in a predetermined direction, thereby improving the reliability of the battery cell 102. Note that the pressure release structure 1025 and the case 1 may be formed integrally, or may be formed separately and then assembled and connected, but this is not limited thereto.

[0297] In the above technical solution, by arranging the liquid injection hole 31 on the pressure release structure 1025, it is possible to prevent the liquid injection hole 31 from occupying space on the case 1 alone. If the polar pillar structure 1020 is arranged on the case 1, a relatively large space for arranging the polar pillar structure 1020 can be saved, which helps to increase the size of the polar pillar structure 1020. Furthermore, since there is no need to perform special processing on the case 1 to open the liquid injection hole 31 on it, it helps to reduce the structural complexity and processing difficulty of the case 1.

[0298] 32 , the pressure release structure 1025 includes a pressure release body 10251 disposed on the polar pillar body 2 and a third seat 10252 attached to the pressure release body 10251. At least a portion of the liquid injection hole 31 is formed on the third seat 10252, and the sealing structure 1022 is fitted to the third seat 10252. It will be understood that in this embodiment, when the mounting portion 8 includes a base 81 and a seat 82 attached to the base 81, and the sealing structure 1022 is fitted to the seat 82 and configured to open or seal the liquid injection hole 31, if the polar pillar structure 1025 is the mounting portion 8, the pressure release body 10251 will be the base 81 and the third seat 10252 will be the seat 82.

[0299] For example, when the sealing structure 1022 is removably fitted to the case assembly 1021, the sealing structure 1022 may be removably fitted to the third base portion 10252. For example, when the sealing structure 1022 includes the first structural member 61 in the above embodiment, the first structural member 61 may be configured to be lock-fitted to and unlocked from the third base portion 10252. For example, when the stopper portions 10211 and the escape holes 10212 are formed on the case assembly 1021 and are positioned around the flow path 1021A in the above embodiment and arranged alternately, the stopper portions 10211 and the escape holes 10212 can both be machined on the third base portion 10252, thereby reducing the difficulty of machining the pressure release body 10251.

[0300] The method of assembling the pressure release body 10251 and the third base 10252 is not limited, and various methods, such as welding, adhesive bonding, fastening, or interference fit, may be selected. For example, the pressure release body 10251 and the third base 10252 are made of the same metal material and connected by welding, which increases the reliability of the connection between them and improves the sealing performance at the connection position. Furthermore, the structural reliability of the third base 10252 itself is relatively high, and the fit with the sealing structure 1022 is relatively stable. Furthermore, when the pressure release body 10251 and the third base 10252 are welded together, even if the welded position between the pressure release body 10251 and the third base 10252 comes into contact during the electrolyte injection process, contamination or corrosion is unlikely to occur at that position, thereby ensuring a relatively high reliability of the connection between the pressure release body 10251 and the third base 10252.

[0301] In some embodiments, the pressure release body 10251 is provided with a third mounting groove that opens away from the accommodating cavity 1A, and at least a portion of the third base portion 10252 is fitted into the third mounting groove, thereby improving the assembly efficiency between the third base portion 10252 and the pressure release body 10251 and the stability of the connection between the third base portion 10252 and the pressure release body 10251, and reducing the space outside the pressure release body 10251 occupied by the third base portion 10252.

[0302] Illustratively, the pressure release structure 1025 does not have to be divided into two parts, the third base portion 10252 and the pressure release body 10251. The liquid injection hole 31, the stopper portion 10211, the escape hole 10212, etc. may be directly processed on the pressure release structure 1025, which does not have the third base portion 10252, and fitted into the sealing structure 1022, thereby omitting the third base portion 10252, reducing the number of parts and improving assembly efficiency.

[0303] Note that the mounting portion 8 according to the embodiments of the present application is not limited to the pressure release structure 1025, and therefore the liquid injection hole 31 is not limited to being formed only on the pressure release structure 1025. For example, in some embodiments, as shown in FIGS. 33 to 35 , a case assembly 1021 includes a case 1 defining a receiving cavity 1A, and a polar pillar structure 1020 and a pressure release structure 1025 are provided on the case 1. The case 1 includes a mounting case wall 14 spaced apart from the polar pillar structure 1020 and the pressure release structure 1025, and a flow path 1021A is provided in the mounting case wall 14 (for example, provided in the mounting portion 8) and includes the liquid injection hole 31. The sealing structure 1022 is fitted to the mounting case wall 14 and configured to open or seal the liquid injection hole 31.

[0304] 35 , the mounting case wall 14 includes a case wall portion 141 and a fourth seat portion 142 attached to the case wall portion 141, at least a portion of the liquid injection hole 31 is formed on the fourth seat portion 142, and the sealing structure 1022 is fitted into the fourth seat portion 142. In this embodiment, when the mounting portion 8 includes a base 81 and a seat 82 attached to the base 81, and the sealing structure 1022 is fitted into the seat 82 and is configured to open or seal the liquid injection hole 31, it will be understood that when the mounting case wall 14 is the mounting portion 8, the case wall portion 141 is the base 81 and the fourth seat portion 142 is the seat 82.

[0305] For example, when the sealing structure 1022 is removably fitted to the case assembly 1021, the sealing structure 1022 may be removably fitted to the fourth pedestal portion 142. For example, when the sealing structure 1022 includes the first structural member 61 in the above embodiment, the first structural member 61 may be configured to be lock-fitted to and then unlocked from the fourth pedestal portion 142. For example, when the stopper portions 10211 and the escape holes 10212 are formed on the case assembly 1021 and are positioned around the flow path 1021A in the above embodiment and arranged alternately, the stopper portions 10211 and the escape holes 10212 can both be machined on the fourth pedestal portion 142, thereby reducing the difficulty of machining the case wall portion 141.

[0306] The method of assembling the case wall 141 and the fourth pedestal 142 is not limited, and various methods, such as welding, adhesive bonding, fastening, or interference fit, may be selected. For example, the case wall 141 and the fourth pedestal 142 are made of the same metal material and connected by welding, which increases the reliability of the connection between them and improves the sealing performance of the connection. Furthermore, the structural reliability of the fourth pedestal 142 itself is relatively high, and the fit with the sealing structure 1022 is relatively stable. Furthermore, when the case wall 141 and the fourth pedestal 142 are welded together, even if the welding position between the case wall 141 and the fourth pedestal 142 comes into contact during the electrolyte injection process, contamination or corrosion is unlikely to occur at that position, and the reliability of the connection between the case wall 141 and the fourth pedestal 142 can be relatively well guaranteed.

[0307] In some embodiments, a fourth mounting groove that opens away from the storage cavity 1A is provided in the case wall portion 141, and at least a portion of the fourth base portion 142 is fitted into the fourth mounting groove, thereby improving the assembly efficiency between the fourth base portion 142 and the case wall portion 141 and the stability of the connection between the fourth base portion 142 and the case wall portion 141, and reducing the space outside the case wall portion 141 occupied by the fourth base portion 142.

[0308] For example, the mounting case wall 14 does not have to be divided into two parts, the case wall portion 141 and the fourth base portion 142. For example, the liquid injection hole 31, the stopper portion 10211, the escape hole 10212, etc. may be directly machined on the wall of the case 1 and fitted into the sealing structure 1022, thereby omitting the fourth base portion 142, reducing the number of parts and improving assembly efficiency.

[0309] In battery cells of related art, a liquid injection hole is typically provided in the top cover of the case, and electrode posts and an explosion-proof valve are mounted on the top cover. The outer end of the liquid injection hole is flush with the outer surface of the top cover, and the inner end of the liquid injection hole is flush with the inner surface of the top cover. After completing the electrical connection between the tabs and electrode posts, electrolyte is injected into the case through the liquid injection hole. If the injection speed is too fast, the electrolyte may backflow and overflow from the liquid injection hole, slowing down the injection speed. Furthermore, the overflowing electrolyte may contaminate and corrode not only the top cover but also the electrode posts and explosion-proof valve on the top cover, affecting the reliability of the battery cell. Furthermore, because the injection height of the electrolyte must not exceed the inner end of the liquid injection hole, the electrolyte level in the case is kept as flush as possible with the inner surface of the top cover. This limits the total amount of electrolyte injected into the case and affects the cycle life of the battery cell.

[0310] 18 , according to some embodiments of the present application, a case assembly 1021 includes a case 1 that defines a storage cavity 1A and includes a first case wall 11. The surface of the first case wall 11 facing the storage cavity 1A is the inner surface 11b, and the surface of the first case wall 11 facing away from the storage cavity 1A is the outer surface 11a. That is, the side of the first case wall 11 facing the storage cavity 1A is the inner surface, and the side of the first case wall 11 facing away from the storage cavity 1A is the outer surface. The flow path 1021A includes a liquid injection hole 31 that is provided directly or indirectly in the first case wall 11, and both ends of the liquid injection hole 31 are the outer hole end 31a and the inner hole end 31b, respectively. The hole outer end 31a and the hole inner end 31b are arranged in order along the direction from the outer surface 11a to the inner surface 11b of the first case wall 11. That is, the hole outer end 31a and the hole inner end 31b are arranged in order along the direction from the outside to the inside. For example, if the upper surface of the first case wall 11 is the outer surface 11a and the lower surface of the first case wall 11 is the inner surface 11b, the hole outer end 31a and the hole inner end 31b are arranged in the direction from top to bottom. In this case, the upper end of the liquid injection hole 31 is the hole outer end 31a, and the lower end of the liquid injection hole 31 is the hole inner end 31b.

[0311] 18, in the embodiment of the present application, the hole inner end 31b is located on the side of the inner surface 11b of the first case wall 11 that is away from the accommodating cavity 1A (i.e., on the outside). That is, the hole inner end 31b of the liquid injection hole 31 is disposed away from the inner surface 11b of the first case wall 11, or the hole inner end 31b of the liquid injection hole 31 is disposed close to the outer side of the inner surface 11b of the first case wall 11. For example, as shown in FIG. 18, the distance by which the hole inner end 31b of the liquid injection hole 31 extends outward beyond the inner surface 11b of the first case wall 11 is defined as H1.

[0312] Therefore, by positioning the hole inner end 31b on the side of the inner surface 11b of the first case wall 11 away from the accommodating cavity 1A (i.e., on the outside), more accommodating space is created inside the hole inner end 31b of the liquid injection hole 31. When injecting the electrolyte, the first case wall 11 is placed horizontally, with the upper surface of the first case wall 11 becoming the outer surface 11a and the lower surface of the first case wall 11 becoming the inner surface 11b. The upper end of the liquid injection hole 31 becomes the hole outer end 31a, and the lower end of the liquid injection hole 31 becomes the hole inner end 31b. The lower end of the liquid injection hole 31 is higher than the lower surface of the first case wall 11. Therefore, by increasing the height of the lower end of the liquid injection hole 31, more accommodating space is created below the liquid injection hole 31, which can serve as a buffer.

[0313] In this way, if the electrolyte is about to overflow during the manufacture, transportation, or use of the battery cell 102, for example, the overflowing electrolyte can enter the storage space, thereby reducing the possibility of the electrolyte overflowing from the liquid injection hole 31 and helping to alleviate the problem of the overflowing electrolyte contaminating the first case wall 11 and components on the first case wall 11 (for example, the pole or the explosion-proof valve), and also helping to increase the injection speed during manufacturing, thereby improving the manufacturability of the battery cell 102 and improving the reliability of the battery cell 102.

[0314] Furthermore, because the height of the lower end of the liquid injection hole 31 is increased, when the level of the injected electrolyte reaches the lower end of the liquid injection hole 31, the level of the injected electrolyte is higher than the lower surface of the first case wall 11, which helps to increase the total amount of electrolyte injected into the case 1 and further helps to extend the cycle life of the battery cell 102. It will be understood that as the electrolyte is consumed during use of the battery cell 102, the electrolyte in the battery cell 102 decreases, which affects the service life of the battery cell 102, and that increasing the total amount of electrolyte injected helps to extend the service life of the battery cell 102.

[0315] Furthermore, during use of the battery cell 102, the electrolyte generates gas after participating in a reaction, causing the pressure inside the case 1 to rise. When the pressure reaches a certain level, reliability issues arise. When gas is generated inside the case 1, the remaining storage space below the liquid injection hole 31 acts as a buffer for the gas, thereby alleviating the reliability issues caused by the pressure rise and improving the usage reliability of the battery cell 102.

[0316] It will also be understood that after the injection of the electrolyte is completed, the liquid injection hole 31 can be sealed with the sealing structure 1022 to prevent leakage of the electrolyte and the intrusion of external contaminants into the case 1 through the liquid injection hole 31. When the liquid injection hole 31 is sealed, the orientation of the first case wall 11 is not limited and may be horizontal or vertical. The first case wall 11 may be located at the top, bottom, side, etc. of the case 1. The orientation of the liquid injection hole 31 also changes as the orientation of the first case wall 11 changes.

[0317] For example, when the battery cells 102 are arranged so that the first case wall 11 forms the upper wall of the case 1, the upper surface of the first case wall 11 becomes the outer surface 11a, and the lower surface of the first case wall 11 becomes the inner surface 11b. The upper end of the liquid injection hole 31 becomes the outer hole end 31a, and the lower end of the liquid injection hole 31 becomes the inner hole end 31b.

[0318] As another example, when the battery cells 102 are arranged so that the first case wall 11 forms the bottom wall of the case 1, the lower surface of the first case wall 11 becomes the outer surface 11a, and the upper surface of the first case wall 11 becomes the inner surface 11b. The lower end of the liquid injection hole 31 becomes the outer hole end 31a, and the upper end of the liquid injection hole 31 becomes the inner hole end 31b.

[0319] As another example, when the battery cell 102 is arranged so that the first case wall 11 forms the left wall of the case 1, the left surface of the first case wall 11 becomes the outer surface 11a, and the right surface of the first case wall 11 becomes the inner surface 11b. The left end of the liquid injection hole 31 becomes the outer hole end 31a, and the right end of the liquid injection hole 31 becomes the inner hole end 31b.

[0320] As another example, when the battery cell 102 is arranged so that the first case wall 11 forms the right wall of the case 1, the right surface of the first case wall 11 becomes the outer surface 11a, and the left surface of the first case wall 11 becomes the inner surface 11b. The right end of the liquid injection hole 31 becomes the outer hole end 31a, and the left end of the liquid injection hole 31 becomes the inner hole end 31b.

[0321] As another example, when the battery cells 102 are arranged so that the first case wall 11 forms the front wall of the case 1, the front surface of the first case wall 11 becomes the outer surface 11a, and the rear surface of the first case wall 11 becomes the inner surface 11b. The front end of the liquid injection hole 31 becomes the outer hole end 31a, and the rear end of the liquid injection hole 31 becomes the inner hole end 31b.

[0322] As another example, when the battery cells 102 are arranged so that the first case wall 11 forms the rear wall of the case 1, the rear surface of the first case wall 11 becomes the outer surface 11a, and the front surface of the first case wall 11 becomes the inner surface 11b. The rear end of the liquid injection hole 31 becomes the outer hole end 31a, and the front end of the liquid injection hole 31 becomes the inner hole end 31b.

[0323] To simplify the explanation, the following will use as an example the following: "The first case wall 11 forms the upper wall of the case 1, the upper surface of the first case wall 11 is the outer surface 11a, and the lower surface of the first case wall 11 is the inner surface 11b. The upper end of the liquid injection hole 31 is the outer hole end 31a, and the lower end of the liquid injection hole 31 is the inner hole end 31b."

[0324] In some embodiments of the present application, as shown in Fig. 18 , a mounting portion 8 is provided on the first case wall 11. At least a portion of the mounting portion 8 protrudes from the outer surface 11a of the first case wall 11 away from the accommodating cavity 1A (i.e., outward). That is, the mounting portion 8 may completely protrude outward from the outer surface 11a of the first case wall 11, or the mounting portion 8 may partially protrude outward from the outer surface 11a of the first case wall 11. For example, when the first case wall 11 is placed horizontally and the upper surface of the first case wall 11 is the outer surface 11a and the lower surface of the first case wall 11 is the inner surface 11b, the mounting portion 8 may be completely higher than the upper surface of the first case wall 11, or only a portion of the mounting portion 8 may be higher than the upper surface of the first case wall 11. By positioning the liquid injection hole 31 on the mounting portion 8, it becomes easy to position the inner end 31b of the liquid injection hole 31 on the side of the inner surface 11b of the first case wall 11 away from the accommodating cavity 1A (i.e., on the outside).

[0325] There are no limitations on the structure, shape, position, etc. of the mounting portion 8. For example, the mounting portion 8 may be a pole post structure 1020 (see, for example, FIG. 18), a pressure release structure 1025 (see, for example, FIG. 31), a mounting case wall 14 (see, for example, FIG. 33), etc.

[0326] For example, when the mounting portion 8 is the polar pillar structure 1020, the polar pillar structure 1020 is provided on the first case wall 11, and at least a portion of the polar pillar structure 1020 protrudes outward from the outer surface 11a of the first case wall 11, and the liquid injection hole 31 is formed on the polar pillar structure 1020. For example, when the first case wall 11 is placed horizontally and the upper surface of the first case wall 11 is the outer surface 11a and the lower surface of the first case wall 11 is the inner surface 11b, the polar pillar structure 1020 may be completely higher than the upper surface of the first case wall 11, or only a portion of the polar pillar structure 1020 may be higher than the upper surface of the first case wall 11. For example, when the mounting portion 8 is the mounting case wall 14, the mounting case wall 14 can be easily obtained by punching out a plate of the case 1 and using the protruding portion as the mounting case wall 14 and the other portion as the first case wall 11.

[0327] 19, the inner end 31b of the liquid injection hole 31 is located on the side of the outer surface 11a of the first case wall 11 away from the accommodating cavity 1A. That is, the inner end 31b of the liquid injection hole 31 is disposed away from the inner side of the outer surface 11a of the first case wall 11, or the inner end 31b of the liquid injection hole 31 is disposed close to the outer side of the outer surface 11a of the first case wall 11. For example, as shown in FIG. 19, the distance by which the inner end 31b of the liquid injection hole 31 extends outward beyond the outer surface 11a of the first case wall 11 is defined as H2.

[0328] Therefore, by locating the inner hole end 31b of the liquid injection hole 31 on the side of the outer surface 11a of the first case wall 11 away from the accommodating cavity 1A, more accommodating space is created inside the inner hole end 31b. For example, when injecting an electrolyte, the first case wall 11 is placed horizontally, with the upper surface of the first case wall 11 becoming the outer surface 11a and the lower surface of the first case wall 11 becoming the inner surface 11b. The upper end of the liquid injection hole 31 becomes the outer hole end 31a, and the lower end of the liquid injection hole 31 becomes the inner hole end 31b. The lower end of the liquid injection hole 31 is higher than the upper surface of the first case wall 11. In this way, the inner hole end 31b is positioned close to the outside of the outer surface 11a of the first case wall 11.

[0329] Therefore, the height of the inner end 31b of the liquid injection hole 31 can be further increased, creating more storage space below the liquid injection hole 31. This further reduces the likelihood of electrolyte overflowing from the liquid injection hole 31 during manufacture, transportation, or use of the battery cell 102, thereby improving the reliability and manufacturability of the battery cell 102. Furthermore, the electrolyte injection height can be made higher than the upper surface of the first case wall 11, which helps to further increase the total amount of electrolyte injected into the case 1 and further helps to extend the cycle life of the battery cell 102. In addition, during use of the battery cell 102, gas is generated after the electrolyte participates in a reaction. This gas can be buffered by more storage space, more effectively alleviating reliability issues caused by pressure increases and further improving the usage reliability of the battery cell 102.

[0330] In some embodiments of the present application, the case 1 includes a first case wall 11, and the case assembly 1021 includes the case 1, with the accommodating cavity 1A defined by the case 1. The case 1 includes the first case wall 11 having a flow path 1021A. Here, as shown in FIG. 18 , the first case wall 11 and at least one second case wall 12 are integrally formed, and the second case wall 12 extends toward one side of the first case wall 11 in the thickness direction. Alternatively, as shown in FIG. 36 , the first case wall 11 is an integrally formed cover plate. This allows for flexible design of the position of the flow path 1021A, thereby broadening the range of application of the battery cell 102 according to the embodiments of the present application.

[0331] It should be noted that the second case wall 12 can extend from an edge of the first case wall 11. If the first case wall 11 is rectangular, at least one of the four edges of the first case wall 11 can extend from the second case wall 12. For example, only one edge of the first case wall 11 extends from the second case wall 12. The first case wall 11 may have only two edges each extending from the second case wall 12, or the first case wall 11 may have three edges each extending from the second case wall 12, or the first case wall 11 may have four edges extending from the second case wall 12. For example, if the case 1 is a rectangular case, any one of the walls of the rectangular case may be the first case wall 11.

[0332] For example, case 1 includes a case body defining a space open on one side, and a cover plate provided on the open side of the case body so as to form an accommodating cavity 1A between the case body and the cover plate. In this case, the wall surface of the case body opposite the cover plate may be the first case wall 11, and the wall surface connected between the first case wall 11 of the case body and the cover plate may be the second case wall 12, or the wall surface of the case body opposite the cover plate may be the second case wall 12, and the wall surface connected between the second case wall 12 of the case body and the cover plate may be the first case wall 11, or the cover plate may be the first case wall 11.

[0333] In a second aspect, referring to FIGS. 2 and 28, the present application further provides a battery 100 including a current collecting member 103 and a battery cell 102 according to any one of the above-described solutions, wherein the battery includes a plurality of battery cells 102, at least two of which are electrically connected via the current collecting member 103. Therefore, it is possible to realize series and / or parallel connection of the plurality of battery cells 102. The battery cell 102 according to the embodiment of the present application has improved reliability in use and service life, which contributes to improving reliability in use and service life of the battery 100. The battery 100 according to the embodiment of the present application may or may not include a housing 101.

[0334] For example, when multiple battery cells 102 are connected in series, the positive electrode pole cover plate 3 of one battery cell 102 is connected to the negative electrode pole cover plate 3 of the next battery cell 102 via one current collecting member 103, while the negative electrode pole cover plate 3 of that battery cell 102 is connected to the positive electrode pole cover plate 3 of the previous battery cell 102 via another current collecting member 103.

[0335] 37 , when the sealing structure 1022 is fitted to the mounting portion 8 and the liquid injection hole 31 is formed on the mounting portion 8, the mounting portion 8 comprises a pole structure 1020 including a pole body 2 and a pole cover plate 3. When the liquid injection hole 31 is formed on the pole cover plate 3, the current collecting member 103 is connected to the surface of the pole cover plate 3 away from the accommodating cavity 1A to form the second connection portion 104 (for example, by forming a weld mark by welding). The liquid injection hole 31 and the second connection portion 104 are positioned offset from each other, i.e., the liquid injection hole 31 and the second connection portion 104 do not overlap each other. Therefore, even if the electrolyte overflows from the liquid injection hole 31, contamination and corrosion of the second connection part 104 due to the electrolyte is reduced, and the sealing structure 1022 covering the liquid injection hole 31 is prevented from affecting the connection between the collecting member 103 and the pole cover plate 3, thereby improving the convenience and reliability of the connection between the collecting member 103 and the pole cover plate 3.

[0336] In some embodiments, as shown in FIG. 37 , a boundary 34 is formed on the surface of the electrode post cover plate 3 away from the receiving cavity 1A. The boundary 34 is located between the second connection portion 104 and the liquid injection hole 31. The boundary 34 has a recessed or protruding structure. When the electrolyte overflows from the liquid injection hole 31, it is separated by the boundary 34, for example, pooling in the recessed structure or being stopped by the protruding structure. This reduces the probability of the electrolyte contacting the second connection portion 104 and reduces contamination and corrosion of the second connection portion 104 by the electrolyte. Furthermore, the boundary 34 can serve as a marking, thereby separating the connection position between the current collecting member 103 and the electrode post cover plate 3 from the liquid injection hole 31 and further reducing contact of the electrolyte overflowing from the liquid injection hole 31 with the second connection portion 104. The shape and size of the boundary 34 are not limited as long as it can separate the liquid injection hole 31 to some extent.

[0337] In a third aspect, an embodiment of the present application further provides an electric device comprising the battery 100 according to any one of the above solutions.

[0338] According to some embodiments of the present application, the embodiments of the present application further provide an electric device including the battery 100 according to any one of the above solutions for supplying electric energy to the electric device. The electric device is any one of the above-mentioned facilities or systems using the battery 100. The improved performance of the battery 100 helps to improve the electric consumption performance during operation of the electric device.

[0339] Next, a battery cell 102 according to a specific embodiment of the present application will be described.

[0340] The battery cell 102 includes a case assembly 1021, a sealing structure 1022, and a cell assembly 7. As shown in FIGS. 3 to 5, the case assembly 1021 defines a storage cavity 1A and has a flow path 1021A that communicates with the storage cavity 1A. The flow path 1021A includes a liquid injection hole 31. The sealing structure 1022 is removably fitted to the case assembly 1021 and is configured to open or seal the liquid injection hole 31.

[0341] 17, the case assembly 1021 includes a case 1 defining a receiving cavity 1A, and a pole structure 1020 including a pole body 2 attached to the case 1 and a pole cover plate 3 covering the pole body 2. The flow path 1021A also includes a communication passage 2A formed on the pole body 2 and communicating with the receiving cavity 1A. A liquid injection hole 31 is formed on the pole cover plate 3 and communicates with the communication passage 2A. A sealing structure 1022 is removably fitted to the pole cover plate 3 to open or close the liquid injection hole 31.

[0342] 17, the pole cover plate 3 includes a cover plate portion 36 that covers the pole body 2 and a first base portion 37 that is attached to the cover plate portion 36. A portion of the liquid injection hole 31 is formed on the first base portion 37, and the remaining portion is formed on the cover plate portion 36. The sealing structure 1022 is fitted into the first base portion 37.

[0343] 18, the case 1 includes a first case wall 11. The surface of the first case wall 11 facing the receiving cavity 1A is the inner surface 11b, and the surface of the first case wall 11 facing away from the receiving cavity 1A is the outer surface 11a. A polar pillar structure 1020 is provided on the first case wall 11. The liquid injection hole 31 has an outer hole end 31a and an inner hole end 31b at both ends, which are arranged in order from the outer surface 11a to the inner surface 11b of the first case wall 11, with the inner hole end 31b being located on the side of the inner surface 11b of the first case wall 11 facing away from the receiving cavity 1A.

[0344] 18, the communication passage 2A includes a first accommodating groove 211 that opens toward the electrode post cover plate 3 and communicates with the liquid injection hole 31, and a liquid passage hole 23 that penetrates the groove wall of the first accommodating groove 211 to communicate between the first accommodating groove 211 and the accommodating cavity 1A. The cell assembly 7 includes an active material applied portion 71 received in the accommodating cavity 1A and a conductive portion 72 connected to the active material applied portion 71. A communication hole 22 that communicates between the first accommodating groove 211 and the accommodating cavity 1A is formed on the electrode post body 2. There are one or more communication holes 22, and at least one of the communication holes 22 is designated as the liquid passage hole 23. The conductive portion 72 penetrates at least one communication hole 22 and is at least partially received in the first accommodating groove 211.

[0345] When manufacturing the battery cell 102, first the conductive part 72 is inserted through the connecting hole 22 in the pole body 2 and welded to the pole body 2. Next, the pole body 2 is covered with the pole cover plate 3, and electrolyte is poured into the case 1 through the liquid pouring hole 31 in the pole cover plate 3. The electrolyte enters the case 1 through the connecting passage 2A in the pole body 2. After the electrolyte has been poured in, a sealing structure 1022 is fitted into the liquid pouring hole 31 to ensure strict sealing.

[0346] It should be noted that, unless a contradiction occurs, the embodiments and features in the embodiments in this application may be combined with each other.

[0347] The above is only a preferred embodiment of the present application and is not intended to limit the present application. Those skilled in the art can make various modifications and changes to the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be considered to be within the scope of protection of the present application. [Explanation of symbols]

[0348] 1000 vehicles X first direction Y Second direction Z third direction 100 batteries 200 Controller 300 motor 101 Case 1011 First housing body 1012 Second housing body 102 battery cells 1020 pole structure 1021 Case Assembly 1021A Flow path A1 First passage A2 Second passage 10211 Stopper part 10212 Avoidance hole 10213 Receptor groove 10214 Support part 10215 First positioning structure 10216 Step surface 8 Mounting part 81 Base 811 Mounting groove 82 Pedestal 1 case 1A Housing cavity 11 First Case Wall 12 Second Case Wall 11a Outer surface of first case wall 11b Inner surface of first case wall 14 Mounting case wall 141 Case wall 142 Fourth Pedestal 2 Pole body 2A communication path 21 Storage groove 211 First Receiving Ditch 212 Second Receiving Ditch 213 Third Storage Ditch 214 Fourth Storage Ditch 215 Fifth Storage Ditch 22 Communication hole 221 First communication hole 222 Second communication hole 23 Liquid passage hole 25 Counterbore 26 Fitting gap 271 Outer stopper part 272 Inner stopper part 28 Main body 29 Second pedestal 1022 Sealing structure 3-pole cover plate 31 Liquid injection hole 31a Hole outer end 31b Hole inner end 32 Edge 331 first cover plate part 332 Second cover plate part 34 Boundary 36 Cover plate part 361 First mounting groove 37 First Pedestal 61 First structural member 611 first fitting portion 612 Tool fitting hole 613 Positioning structure 614 Central part 615 Locking part 6151 Second positioning structure 62 Second structural member 621 Second fitting part 622 Lap joint 1023 Seal gasket 1024 Insulation Gasket 1025 Pressure release structure 10251 Pressure release body 10252 Third Pedestal 7. Cell Assembly 71 Active material coating section 72 Conductive part 73 First Connection 103 Current collecting member 104 Second connection

Claims

1. a case assembly defining a receiving cavity and having a flow passage communicating with said receiving cavity; a sealing structure fitted to the case assembly and configured to open or seal the flow path.

2. The battery cell of claim 1 , wherein the sealing structure is removably fitted to the case assembly.

3. 3. The battery cell of claim 2, wherein the sealing structure comprises a first structural member and a second structural member, the second structural member sealingly fitted to the flow passage, the first structural member lockingly fitted to the case assembly to restrict the second structural member to a position that seals the flow passage, and the first structural member is located on a side of the second structural member away from the accommodating cavity.

4. The battery cell of claim 3 , wherein the first structural member and the second structural member are connected.

5. The battery cell of claim 4 , wherein the first structural member and the second structural member are removably connected.

6. 6. The battery cell of claim 4, wherein the connection between the first structural member and the second structural member allows the first structural member and the second structural member to remain connected when the sealing structure is removed from the case assembly.

7. 7. The battery cell according to claim 4, wherein the first structural member has a first fitting portion on a side facing the second structural member, the second structural member has a second fitting portion on a side facing the first structural member, one of the first fitting portion and the second fitting portion has a convex structure and the other has a concave structure, and the convex structure is fitted into the concave structure.

8. 8. The battery cell according to claim 7, wherein the convex structure and the concave structure are fitted together by an interference fit, a screw fit, or a position restriction structure that restricts the position of the convex structure to prevent the convex structure from escaping from the concave structure.

9. The battery cell according to any one of claims 3 to 8, wherein at least a portion of the first structural member is fitted within the case assembly.

10. The battery cell according to any one of claims 3 to 9, wherein the first structural member is configured to be able to lock and unlock with the case assembly by rotational movement.

11. The battery cell according to claim 10 , wherein a tool fitting hole is provided on a surface of the first structural member away from the second structural member.

12. The battery cell according to claim 10 or 11, wherein a positioning structure is provided on a surface of the first structural member away from the second structural member.

13. 13. The battery cell of claim 10, wherein the first structural member comprises a central portion disposed corresponding to the flow path and a locking portion located in an outer peripheral region of the central portion, and the case assembly is formed with stopper portions and avoidance holes disposed alternately around the flow path, receiving grooves are formed on the side of the stopper portions that is close to the accommodating cavity, the avoidance holes penetrate the surface of the case assembly on the side away from the accommodating cavity and communicate with the receiving groove, and the locking portion rotatably moves in and out of the receiving groove through the avoidance holes.

14. 14. The battery cell of claim 13, wherein the avoidance holes are multiple and spaced apart around the flow path, the stopper portion is provided between each pair of adjacent avoidance holes, the engaging portions are multiple and spaced apart around the central portion, and the engaging portions are arranged corresponding to the multiple avoidance holes, respectively.

15. 15. The battery cell of claim 13 or 14, wherein the case assembly includes a support portion, the second structural member includes a lap joint, and the lap joint is lap-jointed to a side of the support portion away from the storage cavity and is supported on a side of the first structural member close to the storage cavity, or the first structural member is lap-jointed to a side of the support portion away from the storage cavity.

16. 16. The battery cell of claim 13, wherein a first positioning structure is provided on the side of the stopper portion facing the receiving groove, and a second positioning structure is provided on the side of the engaging portion facing the stopper portion, and the engaging portion is prevented from rotating relative to the stopper portion by positioning and fitting the first positioning structure and the second positioning structure.

17. The battery cell according to claim 16 , wherein one of the first positioning structure and the second positioning structure is a protrusion structure and the other is a groove structure, and the protrusion structure and the groove structure are fitted together.

18. 18. The battery cell of claim 17, wherein the protrusion structure includes a plurality of strip ribs spaced apart along the rotational direction of the first structural member, the groove structure includes a plurality of strip grooves spaced apart along the rotational direction of the first structural member, and the plurality of strip ribs are fitted into the plurality of strip grooves in a one-to-one correspondence.

19. 18. The battery cell of claim 17, wherein the protrusion structure includes a bump structure, the groove structure includes an arc-shaped groove extending along the rotation direction of the first structural member, and the bump structure is fitted into the arc-shaped groove.

20. The battery cell according to any one of claims 13 to 19, wherein the central portion is fitted into the flow path, forming a cylindrical surface fit with the flow path.

21. The battery cell according to any one of claims 3 to 20, wherein at least a portion of the second structural member is inserted into the flow passage and is interference-fitted with the flow passage so as to seal the flow passage.

22. 22. The battery cell of claim 21, wherein the first structural member forms a cylindrical insertion fit with the second structural member, thereby allowing the first structural member to rotate relative to the second structural member.

23. 23. The battery cell of claim 21, wherein the flow path includes a first passage portion and a second passage portion arranged in order along a liquid injection direction, the cross-sectional area of ​​the first passage portion is larger than the cross-sectional area of ​​the second passage portion, the second structural member is press-fit into the second passage portion, and at least a portion of the first structural member is fitted into the first passage portion.

24. 24. The battery cell of claim 23, wherein the case assembly has a stepped surface formed at a connection between the first passage portion and the second passage portion, and a portion of the second structural member is supported on a side of the stepped surface away from the storage cavity.

25. 25. The battery cell of claim 23 or 24, wherein the case assembly has a step surface formed at a connection portion between the first passage portion and the second passage portion, and the step surface extends obliquely from the hole wall of the first passage portion toward the second passage portion, in a direction approaching the accommodating cavity.

26. The battery cell according to any one of claims 1 to 25, wherein the sealing structure is configured to be at least partially fitted into the flow path through an inlet of the flow path.

27. 27. The battery cell of claim 1, wherein the case assembly includes a mounting portion, the flow path includes a liquid injection hole formed on the mounting portion, the mounting portion includes a base and a pedestal attached to the base, and the sealing structure is fitted to the pedestal and configured to open or seal the liquid injection hole.

28. 28. The battery cell of claim 1, wherein the case assembly comprises a case defining the accommodating cavity and a pole structure provided in the case, the flow path being provided in the pole structure and including a liquid injection hole, and the sealing structure being fitted to the pole structure and configured to open or seal the liquid injection hole.

29. 29. The battery cell of claim 28, wherein the pole structure comprises a pole body attached to the case and a pole cover plate covered by the pole body, the flow path further includes a communication passage formed on the pole body and communicating with the accommodating cavity, the liquid injection hole is formed on the pole cover plate and communicates with the communication passage, and the sealing structure is fitted to the pole cover plate to open or seal the liquid injection hole.

30. 30. The battery cell of claim 29, wherein the pole cover plate comprises a cover plate portion covered by the pole body and a first base portion attached to the cover plate portion, at least a portion of the liquid injection hole is formed on the first base portion, and the sealing structure is fitted to the first base portion.

31. 31. The battery cell of claim 30, wherein a first mounting groove is provided on the cover plate portion, the first mounting groove opening in a direction away from the accommodating cavity, and at least a portion of the first base portion is fitted into the first mounting groove.

32. 32. The battery cell according to claim 29, wherein the communication passage comprises: a first accommodating groove that opens toward the electrode post cover plate and communicates with the liquid injection hole; and a liquid passage hole that penetrates a groove wall of the first accommodating groove and communicates between the first accommodating groove and the accommodating cavity.

33. 33. The battery cell of claim 32, wherein the communication passage further includes a second accommodating groove located on a side of the first accommodating groove closer to the accommodating cavity, the second accommodating groove opening toward the accommodating cavity and communicating with the accommodating cavity, and the liquid passage hole penetrating a groove wall of the second accommodating groove to communicate between the first accommodating groove and the second accommodating groove.

34. 34. The battery cell according to claim 32 or 33, wherein the battery cell comprises a cell assembly including an active material applied portion received in the accommodating cavity and a conductive portion connected to the active material applied portion, wherein a communication hole that communicates the first accommodating groove and the accommodating cavity is formed on the pole body, the number of the communication holes is one or more, at least one of the communication holes is the liquid passage hole, and the conductive portion passes through at least one of the communication holes and is at least partially received in the first accommodating groove.

35. 29. The battery cell of claim 28, wherein the pole structure comprises a pole body attached to the case, the flow path further includes an accommodating groove formed on the pole body together with the liquid injection hole, the liquid injection hole communicates with the accommodating groove by penetrating a groove wall on a side of the accommodating groove away from a groove opening of the accommodating groove, and the sealing structure is fitted to the pole body to open or seal the liquid injection hole.

36. 36. The battery cell of claim 35, wherein the pole body comprises a main body portion attached to the case and a second base portion attached to the main body portion, at least a portion of the liquid injection hole is formed on the second base portion, and the sealing structure is fitted to the second base portion.

37. 37. The battery cell of claim 35 or 36, wherein the accommodating groove includes a third accommodating groove having a groove opening facing away from the accommodating cavity, and the liquid injection hole penetrates a groove wall of the third accommodating groove on a side closest to the accommodating cavity.

38. 38. The battery cell of claim 37, wherein the accommodating groove further includes a fourth accommodating groove having a groove opening facing toward the accommodating cavity, the fourth accommodating groove being located on a side of the third accommodating groove closer to the accommodating cavity, and the liquid injection hole penetrates a groove wall on a side of the fourth accommodating groove away from the accommodating cavity, thereby connecting the third accommodating groove and the fourth accommodating groove.

39. 37. The battery cell of claim 35 or 36, wherein the storage groove includes a fifth storage groove having a groove opening facing toward the storage cavity, and the liquid injection hole penetrates a groove wall of the fifth storage groove on a side away from the storage cavity.

40. 28. The battery cell of claim 1, wherein the case assembly includes a case that defines the accommodating cavity and a pressure release structure provided on the case, the case assembly having a weakened area in the pressure release structure and / or a connection between the pressure release structure and the case, the flow path being provided in the pressure release structure and including a liquid injection hole, and the sealing structure being fitted to the pressure release structure and configured to open or seal the liquid injection hole.

41. 41. The battery cell of claim 40, wherein the pressure release structure comprises a pressure release body provided on the case and a third seat attached to the pressure release body, at least a portion of the liquid injection hole is formed on the third seat, and the sealing structure is fitted to the third seat.

42. 28. The battery cell of claim 1, wherein the case assembly includes a case that defines the accommodating cavity, a pole structure and a pressure release structure provided on the case, the case including a mounting case wall that is spaced apart from the pole structure and the pressure release structure, the flow path being provided in the mounting case wall and including a liquid injection hole, and the sealing structure being fitted to the mounting case wall and configured to open or seal the liquid injection hole.

43. 43. The battery cell of claim 42, wherein the mounting case wall comprises a case wall portion and a fourth seat portion attached to the case wall portion, at least a portion of the liquid injection hole is formed on the fourth seat portion, and the sealing structure is fitted to the fourth seat portion.

44. 44. The battery cell of claim 1, wherein the case assembly comprises a case defining the storage cavity, the case including a first case wall, a surface of the first case wall facing the storage cavity being an inner surface and a surface of the first case wall away from the storage cavity being an outer surface, the flow path including a liquid injection hole provided directly or indirectly in the first case wall, both ends of the liquid injection hole being an outer hole end and an inner hole end, the outer hole end and the inner hole end being arranged in order along a direction from the outer surface to the inner surface of the first case wall, and the inner hole end being located on a side of the inner surface of the first case wall away from the storage cavity.

45. 45. The battery cell of claim 44, wherein a mounting portion is provided on the first case wall, at least a portion of the mounting portion protruding from an outer surface of the first case wall away from the accommodating cavity, and the liquid injection hole is provided in the mounting portion.

46. 46. ​​The battery cell of claim 44 or 45, wherein the inner end of the hole is located on the outer surface of the first case wall away from the storage cavity.

47. 47. The battery cell of claim 1, wherein the case assembly comprises a case defining the accommodating cavity, the case including a first case wall in which the flow path is provided, the first case wall being an integrally formed cover plate or being integrally formed with at least one second case wall, the second case wall extending toward one side in a thickness direction of the first case wall.

48. A battery comprising a current collecting member and the battery cell according to any one of claims 1 to 47, wherein there are a plurality of the battery cells, and at least two of the battery cells are electrically connected via the current collecting member.

49. 49. An electrical device comprising the battery of claim 48.

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