Battery Connecting Piece, Top Cover Assembly and Lithium Battery

Disclosed are a battery connecting piece, a top cover assembly and a lithium battery. The battery connecting piece includes a first current collector and a second current collector, the first current collector is connected to the second current collector in a rotatable manner, the first current collector is configured to be connected to a top cover of a battery, the second current collector is configured to weld a tab of a cell, and an extension direction of a central axis of the second current collector rotating relative to the first current collector is perpendicular to a plane where the top cover is located in a state that the first current collector is connected to the top cover. The battery connecting piece drives the tab to fold more smoothly to prevent the tab from being torn, a bending precision of the tab is improved, and a product consistency is improved.

CROSS-REFERENCE TO RELATED APPLICATION

The disclosure claims priority to and the benefit of Chinese Patent Application No. 202222047807.3, filed to the China National Intellectual Property Administration (CH IPA) on 4 Aug. 2022, which is hereby incorporated by reference in its entirety.

TECHNICAL FIELD

The disclosure relates to the technical field of batteries, and in particular to a battery connecting piece, a top cover assembly, and a lithium battery.

BACKGROUND

At present, different from common cells that having tabs lead out of the end surface, cells of some lithium batteries on the market that having tabs lead out of the side surface are affected by the lengths of the tabs, resulting in a serious waste of internal space of the case. In order to solve the problem of space waste, current collectors of some lithium batteries are bent after welding with the tabs, so as to drive the tabs to fold to an angle roughly parallel to the side surface of the cell.

Then, in the actual operation process, because the current collector is made of metal, there is a sudden change in stroke in the bending process, and the bending process is not smooth enough, often leading to the tear of the tabs, and the degree of bending of the current collector and the tab is difficult to accurately control, resulting in poor product consistency.

SUMMARY

The purpose of the disclosure is to provide a battery connecting piece, a top cover assembly and a lithium battery, which drive a tab to fold more smoothly to prevent the tab from being torn, improve a bending precision of the tab, and improve a product consistency.

The disclosure provides a technical solution as follows.

Some embodiments of the disclosure provide a battery connecting piece, which includes a first current collector and a second current collector. The first current collector is connected to the second current collector in a rotatable manner, the first current collector is configured to be connected to a top cover of a battery, the second current collector is configured to weld a tab of a battery cell, and an extension direction of a central axis of the second current collector rotating relative to the first current collector is perpendicular to a plane where the top cover is located in a state that the first current collector is connected to the top cover.

In some embodiments, the second current collector is configured to rotate from a first state to a second state relative to the first current collector, in the first state, an included angle is formed between a plane where the second current collector and a plane where the first current collector is located, and in the second state, the plane where the second current collector is located is parallel to the plane where the first current collector is located.

In some embodiments, the first current collector is convexly provided with a bearing pedestal, the second current collector is convexly provided with a mating portion, the mating portion is embedded into the bearing pedestal, and the battery connecting piece further includes a rotating shaft, the rotating shaft penetrates through the mating portion and is matched with the bearing pedestal in a rotatable manner, and an extension direction of the rotating shaft is perpendicular to the plane where the top cover is located in a state that the first current collector is connected to the top cover.

In some embodiments, a radius of the rotating shaft is ranges from 1.8 mm to 4 mm;

a length of the rotating shaft ranges from 10 mm to 50 mm.

In some embodiments, the battery connecting piece further includes a spring, the spring is sleeved on the rotating shaft, one end of the spring abuts against a side of the mating portion away from the plastic member, and the other end of the spring abuts against the bearing pedestal.

Some other embodiments of the disclosure further provide a top cover assembly, including a top cover, a plastic member, and the battery connecting piece, the battery connecting piece includes the first current collector and the second current collector, the first current collector is connected to the second current collector in a rotatable manner, the first current collector is configured to be connected to the top cover of the battery, the second current collector is configured to weld the tab of the cell, and the extension direction of the central axis of the second current collector rotating relative to the first current collector is perpendicular to the plane where the top cover is located in a state that the first current collector is connected to the top cover. The top cover and the first current collector are respectively arranged on two opposite sides of the plastic member, the top cover is provided with a conductive block, and the first current collector is connected to the conductive block.

In some embodiments, a side of the plastic member away from the top cover is provided with a locking portion, and the locking portion is configured to lock the second current collector when the second current collector rotates to a second state.

In some embodiments, the locking portion protrudes from a surface of the plastic member, two opposite sides of the locking portion are provided with a guide surface and a stop surface respectively, a locking gap is formed between the stop surface and the first current collector, and the guide surface is configured to guide the second current collector over the locking portion and into the locking gap.

In some embodiments, the locking portion is a groove concavely arranged in a surface of the plastic member, and an extension direction of the groove is parallel to a plane where the first current collector is located.

Some still other embodiments of the disclosure further provide a lithium battery, including a cell and the top cover assembly. The top cover assembly includes the top cover, the plastic member, and the battery connecting piece. The battery connecting piece includes the first current collector and the second current collector. The first current collector is connected to the second current collector in a rotatable manner, the first current collector is configured to be connected to the top cover of the battery, the second current collector is configured to weld the tab of the cell, and the extension direction of the central axis of the second current collector rotating relative to the first current collector is perpendicular to the plane where the top cover is located when the first current collector is connected to the top cover. The top cover and the first current collector are respectively arranged on two opposite sides of the plastic member, the top cover is provided with the conductive block, and the first current collector is connected to the conductive block. The tab of the cell is welded with the second current collector.

Compared with the related art, according to the battery connecting piece provided by the disclosure, the second current collector is connected to the first current collector in a rotatable manner, the first current collector is configured to be connected to the conductive block on the top cover, and the second current collector is configured to weld the tab of the cell. In practical application, according to a plane where the tab is located, an angle of the second current collector relative to the first current collector is adjusted, so that the second current collector and the tab are attached in a face-to-face manner and welded, after the welding is completed, the second current collector is adjusted to rotate relative to the first current collector, so as to drive the tab to fold to a specific angle to avoid occupying too much space in a case. Because the second current collector is connected to the first current collector in a rotatable manner, so that a rotation process is smoother than a bending process of an existing current collector, an operation is convenient, and a rotation angle is easy to control. Therefore, the battery connecting piece provided by the disclosure has the beneficial effects that: driving the tab to fold more smoothly to prevent the tab from being torn, a bending precision of the tab is improved, and a product consistency is improved.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In order to make the purposes, technical solutions and advantages of the embodiments of the disclosure clearer, the technical solutions in the embodiments of the disclosure will be clearly and completely described below in combination with the drawings in the embodiments of the disclosure. It is apparent that the described embodiments are a part of the embodiments of the disclosure, and not all of them. Components of the embodiments of the disclosure generally described and illustrated in the drawings herein may be arranged and designed in a variety of different configurations.

Therefore, the following detailed description of the embodiments of the disclosure provided in the drawings is not intended to limit the scope of the claimed disclosure, but only represents the selected embodiments of the disclosure. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the disclosure without creative efforts are within the scope of protection of the disclosure.

It is to be noted that: similar reference signs and letters refer to similar items in the following drawings, so that once a certain item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

In the description of the disclosure, it is to be noted that the orientations or positional relationships indicated by the terms “upper”, “down”, “inside”, “outside”, “left”, “right”, etc. are based on the orientations or positional relationships shown in the drawings, or the orientations or positional relationships that are conventionally placed when the disclosure product is used, or the orientations or positional relationships that are conventionally understood by those skilled in the art, and are only for the convenience of describing the disclosure and simplifying the description. The description does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as limiting the disclosure.

In addition, the terms “first” and “second” are used for distinguishing the description only, and cannot be understood as indicating or implying relative importance.

In the description of the disclosure, it is also to be noted that, the terms “set”, “connect”, etc. should be broadly understood, unless otherwise specified and defined, for example, may be fixedly connected, or detachably connected, or integrally connected; may be mechanically connected, or electrically connected; and may be directly connected or indirectly connected through an intermediate medium, and may be the internal communication of two elements. The specific meaning of the above-mentioned terminology in the disclosure may be understood by those of ordinary skill in the art in specific circumstances.

The specific embodiments of the disclosure are elaborated in detail below with reference to the drawings.

Referring toFIG.1,FIG.1shows a structural schematic diagram of a top cover assembly100according to Embodiment 1.

A top cover assembly100provided by the embodiment includes a battery connecting piece, a plastic member130, and a top cover140. The battery connecting piece includes a first current collector110and a second current collector120. The top cover140and the first current collector110are respectively arranged on two opposite sides of the plastic member130, the top cover140is provided with a conductive block141, the first current collector110is connected to the conductive block141, the second current collector120is connected to the first current collector110in a rotatable manner, and the second current collector120is configured to weld a tab210of a cell200.

Considering that in practical application, the top cover140covers a top end of a case, and in a case where the tab210is led out of a side surface of the cell200, it is necessary to fold the tab210from a state extending perpendicular to the side surface of the cell200to a state parallel to the side surface of the cell200to save an internal space of the case. Therefore, in the embodiment, an extension direction of a central axis of the second current collector120rotating relative to the first current collector110is perpendicular to a plane where the plastic member130is located.

The second current collector120is configured to rotate from a first state to a second state relative to the first current collector110, in the first state, an included angle is formed between a plane where the second current collector120is located and a plane where the first current collector110is located, and in the second state, the plane where the second current collector120is located is parallel to the plane where the first current collector110is located.

Referring toFIGS.2-3,FIG.2shows a structural schematic diagram of a connection between the second current collector120and the tab210of the cell200when the second current collector120rotates to the first state relative to the first current collector110, andFIG.3shows a structural schematic diagram of a connection between the second current collector120and the tab210of the cell200when the second current collector120rotates to the second state relative to the first current collector110.

Actually, in the first state, the plane where the second current collector120is located is perpendicular to the plane where the first current collector110is located. In a case that the tab210is led out of the side surface, in the first state, the plane where the second current collector120is located is parallel to the plane where the tab210is located, that is, the second current collector120is actually perpendicular to the side surface of the cell200and the first current collector110is parallel to the side surface of the cell200.

In the first state, the second current collector120is arranged face to face with the tab210. At this time, the second current collector120and the tab210are attached and welded together. Because the second current collector120is perpendicular to the side surface of the cell200, a large space between the side surface of the cell200and an inner side wall of the case is occupied. In order to reduce a space occupation, the second current collector120is driven to rotate to the second state relative to the first current collector110.

When the second current collector120drives the tab210to rotate to the second state, the second current collector120is parallel to the first current collector110. At this time, all of the second current collector120, the first current collector110and the tab210are parallel to the side surface of the cell200and an inner side wall of the case. In this state, a width of space occupied between the side surface of the tab210and the inner side wall of the case is only a sum of thicknesses of the first current collector110, the second current collector120, and the tab210. Compared with the first state, a space occupancy rate is greatly reduced.

Because the second current collector120is matched with the first current collector110in a rotatable manner, a process of driving the tab210to rotate relative to the first current collector110by the second current collector120is smoothly performed, which prevents a sudden change in stroke and protects the tab210from being torn.

Compared with bending of the current collector to a specific angle, a rotation of the second current collector120to a specific angle relative to the first current collector110is easier to realize and easy to adjust, that is, the second current collector120is able to rotate more accurately to the specific angle, which significantly improves a product consistency during a mass production process.

In the embodiment, the battery connecting piece further includes a rotating shaft150. The second current collector120is matched with the first current collector110in a rotatable manner by the rotating shaft150. Actually, the first current collector110is convexly provided with a bearing pedestal111, the second current collector120is convexly provided with a mating portion121, the mating portion121is embedded into the bearing pedestal111, the rotating shaft150penetrates through the mating portion121and is matched with the bearing pedestal111in a rotatable manner, and an extension direction of the rotating shaft150is perpendicular to a plane where the plastic member130is located.

It is understandable that, in other embodiments, arrangement positions of the bearing pedestal111and the mating portion121are also exchangeable, that is, the bearing pedestal111is arranged on the second current collector120, the mating portion121is arranged on the first current collector110, and the mating portion121is also matched with the bearing pedestal111in a rotatable manner by the rotating shaft150.

In other embodiments, the first current collector110is rotatably matched with the second current collector120in a smoother rotatably matched manner in other rotation processes.

In the embodiment, the rotating shaft150is an independent component. In order to meet a current passing requirement, a radius of the rotating shaft150ranges from 1.8 mm to 4 mm. If the radius exceeds 4 mm, the overflowing requirement exceeds the standard, which excessively increases a weight of the overall structure, and is not conducive to the rotation of the second current collector120. If the radius is less than 1.8 mm, the current passing requirement will be not met. Moreover, a length of the rotating shaft150is between and 50 mm, if less than 10 mm, the strength is not enough, and if more than 50 mm, the overall weight is too large.

In other embodiments, the rotating shaft150is also integrated with the mating portion121, that is, the rotating shaft150is part of a body of the second current collector120, so as to avoid a gap with the inner side wall of the mating portion121when the rotating shaft150penetrates through the mating portion121, resulting in a sudden change in stroke during the rotation process.

Referring toFIGS.4-5,FIG.4shows an enlarged diagram of an area A inFIG.2, andFIG.5shows an enlarged diagram of an area B inFIG.3.

In order to ensure a precise rotation of the second current collector120, the side of the plastic member130away from the top cover140is provided with a locking portion131, and the locking portion131is configured to lock the second current collector120when the second current collector120rotates from the first state to the second state.

In the embodiment, the locking portion131protrudes from a surface of the plastic member130, two opposite sides of the locking portion131are provided with a guide surface1311and a stop surface1312respectively, a locking gap132is formed between the stop surface1312and the first current collector110, and the guide surface1311is configured to guide the second current collector120over the locking portion131and into the locking gap132.

In practical application, by prearranging a relative positional relationship between the second current collector120and the locking portion131in a vertical direction, it is ensured that the guide surface1311of the locking portion131stops a rotation stroke of the second current collector120rotating from the first state to the second state. When the second current collector120rotates at a certain angle, the end of the second current collector120close to the plastic member130is in contact with the guide surface1311, and the guide surface1311is an inclined plane structure, the second current collector120has a certain elastic deformation ability, and as the second current collector120continues rotating, the second current collector120slides on the guide surface1311.

When the second current collector120is embedded into the locking gap132over the locking portion131under a guidance of the guide surface1311, the second current collector120just rotates to the second state, and a plane where the stop surface1312is located and a plane where the first current collector110is located are both perpendicular to the plane where the plastic member130is located. At this time, the stop surface1312and the first current collector110realize a positioning locking on the second current collector120.

Referring toFIGS.6-8,FIG.6shows a structural schematic diagram of a top cover assembly100according to Embodiment 2,FIG.7shows a structural schematic diagram of a connection between a second current collector120and a tab210of a cell200when the second current collector120is in a first state, andFIG.8shows a structural schematic diagram of a connection between the second current collector120and the tab210of the cell200when the second current collector120is in a second state.

The top cover assembly100provided by the embodiment differs from Embodiment 1 in a structure of a locking portion131and the fact that the top cover assembly100in the embodiment further includes a spring160, and the rest of the features are exactly the same as those in Embodiment 1.

Referring toFIGS.9-11,FIG.9shows an enlarged diagram of an area C inFIG.6, andFIG.10shows an enlarged diagram of an area D inFIG.7.FIG.11shows an enlarged diagram of an area E inFIG.8.

As in Embodiment 1, in the embodiment, the first current collector110is convexly provided with the bearing pedestal111, the second current collector120is convexly provided with the mating portion121, the mating portion121is embedded into the bearing pedestal111, the rotating shaft150penetrates through the mating portion121and is matched with the bearing pedestal111in a rotatable manner, and an extension direction of the rotating shaft150is perpendicular to a plane where the plastic member130is located.

The embodiment differs from Embodiment 1 in that the locking portion131is a groove concavely arranged in the surface of the plastic member130, and the top cover assembly100further includes the spring160. The spring160is sleeved on the rotating shaft150, one end of the spring160abuts against a side of the mating portion121away from the plastic member130, and the other end of the spring160abuts against the bearing pedestal111. The spring160is configured to push the second current collector120to be embedded into the groove when the second current collector120rotates to the second state.

Actually, in the state shown inFIG.6, the second current collector120rotates out of a range of the plastic member130. At this time, the spring160extends to a maximum stroke to push the second current collector120beyond the lower surface of the plastic member130. In a process of rotating the second current collector120from the state shown inFIG.6to the first state shown inFIG.7, an external force is applied to the second current collector120, so that the second current collector120extrudes the spring160, and the end wall of the second current collector120is slightly lower than the lower surface of the plastic member130to ensure that the second current collector120smoothly rotates to the first state without being blocked by the plastic member130.

In the first state, the second current collector120is continuously pressed by the plastic member130, that is, the spring160is kept in a compressed state. In this state, the second current collector120and the tab210of the cell200are attached in a face-to-face manner and welded, and after welding, the second current collector120is pushed to rotate to the second state. The locking portion131as the groove is just arranged at a position when the second current collector120is in the second state. When the second current collector120rotates to the second state, one end of the second current collector120abutting against the plastic member130is embedded into the groove under the vertical upward thrust applied by the spring160, and the groove realizes an accurate positioning of the plastic member130.

In order to minimize a space occupancy rate in the second state, in the embodiment, the extension direction of the groove is parallel to the plane where the first current collector110is located, and a width size of the groove corresponds to that of the second current collector120, so as to ensure that the second current collector120is just parallel to the first current collector110when the second current collector120is embedded into the groove, that is, parallel to a side surface of the cell200and an inner side wall of the case.

It is to be noted that rotatable matched manners of the second current collector120and the first current collector110and a specific structure of the locking portion131are not limited to the records of Embodiment 1 and Embodiment 2 of the disclosure, and are adaptively adjusted according to the actual application conditions.

In summary, according to the top cover assembly100provided by the disclosure, the tab210is driven to fold more smoothly, the tab210is prevented from being torn, the bending precision of the tab210is improved, and the product consistency is improved.

In addition, some embodiments also provide a lithium battery, including the cell200and the top cover assembly100corresponding to any one of the above two embodiments. The tab210of the cell200is welded with the second current collector120. It is understandable that the lithium battery further includes conventional structures such as the case, an upper plastic member, etc., which are not additionally described in the embodiment.

Because the second current collector120is matched with the first current collector110in a rotatable manner, the process of driving the tab210to rotate relative to the first current collector110by the second current collector120is smoothly performed, which prevents a sudden change in stroke and protects the tab210from being torn. Moreover, compared with bending of the current collector to a specific angle, the rotation of the second current collector120to a specific angle relative to the first current collector110is easier to realize and easy to adjust, that is, the second current collector120rotates more accurately to a specific angle, which significantly improves the product consistency in the mass production process.

Therefore, the lithium battery provided by the embodiment prevents the tab210from being torn during the production process, the bending precision of the tab210is high, and the product consistency is high.

The above are only the specific embodiments of the disclosure and are not intended to limit the disclosure. For those skilled in the art, the disclosure may have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc. within the spirit and scope of the disclosure shall fall within the scope of protection of the disclosure.