Novel lithium-ion battery structure

Abstract

The present utility model relates to the technical field of lithium batteries. Disclosed is a novel lithium-ion battery structure. The present utility model comprises a cover plate assembly and a battery cell; the battery cell comprises a jelly roll and tabs connected to the jelly roll, and each tab is divided into at least one tab cluster; the cover plate assembly comprises a substrate and poles; each pole is provided with at least one through hole; the battery cell is located on the inner side of the substrate; the tab clusters pass through the through holes on the poles from the inner sides of the poles to the outer sides of the poles, and are bent to a pole platform of the poles to be directly connected to the poles. In the novel lithium-ion battery structure provided by the solution, the tab clusters are bent, and the tab clusters pass through the poles and are bent to the pole platform to be welded to the pole platform, thereby reducing the space occupied by bending of thick and large tabs, and solving the problem of being difficult to bend the thick and large tabs. In addition, a connecting piece structure is omitted, and the tabs are directly connected to the poles, thereby greatly reducing the physical impedance of a battery, and enhancing the over-current capability of a battery cell.

Description

A novel lithium ion battery structure TECHNICAL FIELD

[0001] The utility model relates to lithium ion battery technical field more specifically, relate to a novel lithium ion battery structure. BACKGROUND

[0002] Lithium ion battery is a commonly used secondary battery, has high energy density, no memory effect, single cycle long, high -efficient clean and pollution free characteristics, is widely used in new energy field, for example new energy power automobile etc., along with the wide application of lithium ion battery, the market to lithium ion battery's endurance and energy demand higher and higher, in order to improve the endurance and energy of lithium ion battery, one of the ways is to further improve the battery package volume and weight, but this kind of mode usually will cause tab to be big and thick, will cause tab to be thick tab bending easily broken, difficult to realize the automatic bending production, and tab is thick, through the conventional mode carries out tab bending, tab area will occupy the larger space in the battery, is not favorable to improve the energy density of battery, and tab thickness is thick and will lead to unable to carry out ultrasonic welding or laser welding, reduces the production density of battery.

[0003] In addition, the existing battery structure is usually that the tabs of the winding core are connected with the connecting sheets and the pole posts in sequence, and the connection path is long, thereby increasing the physical impedance of the battery and reducing the overcurrent capacity.

[0004] After searching, the patent with publication number CN115117569A discloses a square aluminum shell lithium ion power battery, which comprises a battery shell, tabs, a core package, a pole post and a top cover plate, in the scheme, the tabs are bent in the battery, and the top end of the bent tabs is welded and fixed with the bottom end of the pole post. For larger and thicker tabs, the tab bending in the scheme will occupy a large space, which is not conducive to improving the energy density of the battery.

[0005] Therefore, the existing battery structure still needs to be further improved and optimized.

[0006] Utility model content

[0007] The utility model provides a novel lithium ion battery structure to solve the problems of thick and large tabs difficult to bend, large space occupied after bending and the existing battery structure not being compact enough.

[0008] To achieve the above purpose, the technical scheme provided by the utility model is:

[0009] A novel lithium ion battery structure, comprising a cover plate assembly and a core,

[0010] The core comprises a winding core and tabs connected with the winding core, each tab is divided into at least one tab cluster.

[0011] The cover plate assembly comprises a base plate and a pole column;

[0012] At least one through hole is formed on the pole column;

[0013] The electric core is located on the inner side of the base plate, the tab cluster is passed through the through hole on the pole column from the inner side of the pole column to the outer side of the pole column, and is bent to the pole column platform of the pole column to be directly connected with the pole column.

[0014] The new lithium ion battery structure provided in the scheme bends the tab cluster, and the tab cluster is bent through the pole column to the pole column platform and welded to the pole column platform, which reduces the space occupied by thick tab bending and solves the problem of thick tab bending difficulty. At the same time, the connecting sheet structure is cancelled, and the tab is directly connected with the pole column, which greatly reduces the physical impedance of the battery and improves the overcurrent capacity of the electric core.

[0015] As an embodiment, the tab includes a positive tab and a negative tab, and the positive tab and the negative tab are located on the same side of the winding core. The positive tab and the negative tab are arranged on the same side of the winding core, which is beneficial to reduce the space occupied by a single battery and improve the energy density of the battery pack.

[0016] As another embodiment, the tab includes a positive tab and a negative tab, and the positive tab and the negative tab are located on opposite sides of the winding core. The new lithium ion battery structure in the scheme is suitable for more battery structures.

[0017] As a further improvement, the pole column includes a positive pole column and a negative pole column, and a first through hole and a second through hole are formed on the positive pole column at the pole column platform; the structure of the negative pole column is consistent with that of the positive pole column. The through hole is formed on the pole column for the tab cluster to pass through.

[0018] In an embodiment, the cover plate assembly further comprises a pressing plate, and the pressing plate comprises a positive pressing plate and a negative pressing plate; the positive pressing plate is located on the outer side of the positive pole column, and the negative pressing plate is located on the outer side of the negative pole column. A pole column step is formed at the connection between the outer side of the positive pole column and the positive pressing plate, and the edge of the positive pressing plate is connected with the pole column step; the connection mode of the negative pole column and the negative pressing plate is consistent with that of the positive pole column and the positive pressing plate. The positive pressing plate is arranged to seal the positive pole column by welding, and the negative pressing plate is arranged to seal the negative pole column by welding.

[0019] As a preferred embodiment, the negative pressure plate is a composite pressure plate, which comprises a first negative pressure plate and a second negative pressure plate connected together; the first negative pressure plate is further connected with the negative pole post, and the first negative pressure plate is surrounded by the second negative pressure plate. One side of the first negative pressure plate is recessed to form a recess, and the second negative pressure plate is accommodated in the recess. The negative pressure plate adopts an inlaid copper-aluminum composite pressure plate, the first negative pressure plate is connected with the negative pole post for sealing, and the second negative pressure plate can support PACK welding and play a role in overcurrent discharge.

[0020] In another embodiment, an insulating sealing member is further arranged between the substrate and the pole post. The insulating sealing member is arranged between the substrate and the pole post to insulate and seal the substrate and the pole post, so as to avoid the risk of short circuit of the battery.

[0021] Preferably, the substrate, the pole post and the insulating sealing member are connected together by an integrated molding mode, so as to improve the structural strength of the cover plate assembly. BRIEF DESCRIPTION OF DRAWINGS

[0022] Fig. 1 is a schematic view of a battery cover plate structure according to an embodiment;

[0023] Fig. 2 is a schematic view of a positive pole post or a negative pole post structure;

[0024] Fig. 3 is a schematic view of a negative pressure plate structure;

[0025] Fig. 4 is a front view of a battery cover plate according to an embodiment;

[0026] Fig. 5 is a sectional view of C-C in Fig. 4;

[0027] Fig. 6 is a sectional view of E-E in Fig. 4.

[0028] Reference signs: 1, positive pressure plate; 2, negative pressure plate; 21, first negative pressure plate; 211, bottom of negative pressure plate; 22, second negative pressure plate; 3, positive pole post; 31, first through hole; 32, second through hole; 33, pole post platform; 34, pole post step; 4, negative pole post; 5, insulating sealing member; 6, substrate; 7, stop frame; 8, tab. DETAILED DESCRIPTION

[0029] In order to further understand the content of the present application, the present application will be described in detail in combination with the drawings and embodiments.

[0030] The structure, proportion, size and the like shown in the drawings of the specification are only used to cooperate with the content disclosed in the specification, to be understood and read by those skilled in the art, and do not have technical substantive significance, and any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects and purposes that can be achieved by the present application, should still fall within the scope of the technical content disclosed by the present application.

[0031] Meanwhile, the terms such as "upper", "lower", "left", "right", "intermediate", "inner", "outer" and the like cited in the specification are only for the convenience of clear description, and are not used to limit the implementable range, and the change or adjustment of the relative relationship, without substantially changing the technical content, is also considered as the implementable scope of the present application. Moreover, in addition to being used to represent the orientation or position relationship, the above-mentioned terms can also be used to represent other meanings, for example, the term "upper" can also be used to represent a certain attachment relationship or connection relationship in some cases. For those skilled in the art, the specific meanings of these terms in the present application can be understood according to the specific circumstances.

[0032] It should be noted that the terms "first", "second" and the like in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily describe a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein.

[0033] The present application provides a novel lithium ion battery structure, which is mainly installed on a power automobile to drive its operation. The novel lithium ion battery structure has a high energy density, and the connecting sheet structure is cancelled in the cover plate assembly, so that the structure of the cover plate assembly is more simplified, and the battery structure is more compact. Meanwhile, the tab of the cell in the novel lithium ion battery structure is relatively thick, and the bending of the tab is realized through the cooperation of the tab and the pole, so as to reduce the space occupied by the bending of the tab. The specific structure of the novel lithium ion battery structure will be described in detail in combination with the embodiments.

[0034] Embodiment 1

[0035] As shown in FIG. 1, the novel lithium ion battery structure provided in the present embodiment includes a cover plate assembly and a cell. The cell includes a roll core (not shown in the figure) and a tab 8 connected with the roll core, and each tab 8 is divided into at least one tab cluster. The tab 8 can be divided into a plurality of tab clusters according to the thickness, for example, in the present embodiment, one tab 8 is divided into two tab clusters, and the single tab cluster is bent during bending, which can effectively avoid the condition that one tab 8 is difficult to bend due to its thickness. In other cases, one tab 8 can also be divided into other number of tab clusters.

[0036] The cover plate assembly includes a base plate 6 and a pole, and the pole has at least one through hole corresponding to the number of the tab clusters. For example, two through holes are provided in the pole in the embodiment.

[0037] The electric core is located on the inner side of the base plate 6. When the electric core and the cover plate assembly are connected to form a battery, the side close to the electric core is the “inner side”, and the opposite side is the “outer side”. The tab cluster passes through the through hole on the pole from the inner side of the pole to the outer side of the pole, and is bent to the pole platform 33 of the pole to be directly connected with the pole. One side of the pole is the pole platform 33, and the side of the pole is recessed to form a pole groove, and the bottom surface of the pole groove is the pole platform 33.

[0038] The battery with high energy density is usually large in volume and weight, and the tab 8 is thick and large. When the entire tab 8 is bent and connected, it is usually difficult to bend or occupies a large space. In the embodiment, the single tab 8 is divided into two tab clusters, and the divided tab clusters are thinner than the tab 8. Each tab cluster is bent, so it is easier to bend, and the bending occupies a smaller space. After bending, the tab cluster can be laser welded or ultrasonic welded. Further, as shown in FIGS. 4, 5 and 6, in the embodiment, the tab cluster passes through the through hole on the pole and is bent to the pole platform 33 of the pole. The space occupied by the tab cluster bending is within the space of the pole, so that the tab cluster bending does not occupy or less occupies the space outside the pole, so that the battery structure is more compact, thereby further improving the energy density of the battery. In addition, in the embodiment, the tab cluster is bent to the pole platform 33 of the pole, which can be connected to the pole platform 33 by welding and the like, so that the tab 8 is directly connected with the pole. Compared with the conventional battery structure, the connection sheet structure is cancelled. After the connection sheet is cancelled, the tab 8 is directly connected with the pole, which greatly reduces the physical impedance and improves the overcurrent capacity of the electric core. At the same time, the connection sheet is cancelled, and each tab cluster is welded to the pole platform 33, which greatly reduces the tab bending space and improves the utilization rate of the internal space of the electric core. At the same time, the production process of the electric core is simplified, and the manufacturing efficiency and yield are improved.

[0039] In one embodiment, the tab 8 includes a positive tab and a negative tab, and the positive tab and the negative tab are located on the same side of the winding core, as shown in FIG. 1. The positive tab and the negative tab on the same side of the winding core can reduce the height of a single battery, which is more conducive to improving the energy density of the battery.

[0040] As shown in Fig. 2, the pole post includes a positive pole post 3 and a negative pole post 4, the positive pole post 3 is provided with a first through hole 31 and a second through hole 32 at a pole post platform 33. The positive pole tab is divided into two pole tab clusters, which respectively pass through the first through hole 31 and the second through hole 32 and are bent to the pole post platform 33. The structure of the negative pole post 4 is consistent with that of the positive pole post 3. Similarly, the negative pole tab is divided into two pole tab clusters, which respectively pass through two through holes on the negative pole post 4 and are bent to the pole post platform. More specifically, the positive pole post 3 and the negative pole post 4 have the same structure, but the materials of the two are different. The positive pole post 3 is made of aluminum, and the negative pole post 4 is made of copper.

[0041] As a further improvement, the cover plate assembly further includes a pressing plate, which includes a positive pressing plate 1 and a negative pressing plate 2. The positive pressing plate 1 is located on the outer side of the positive pole post 3, and the negative pressing plate 2 is located on the outer side of the negative pole post 4. Specifically, a pole post step 34 is provided at the connection between the outer side of the positive pole post 3 and the positive pressing plate 1, and the edge of the positive pressing plate 1 is connected with the pole post step 34. The provision of the pole post step 34 can make the positive pressing plate 1 more convenient to be welded and sealed with the positive pole post 3. The connection mode of the negative pole post 4 and the negative pressing plate 2 is consistent with that of the positive pole post 3 and the positive pressing plate 1.

[0042] As a preferred embodiment, as shown in Fig. 3, the negative pressing plate 2 is a composite pressing plate, which includes a first negative pressing plate 21 and a second negative pressing plate 22 connected together. The first negative pressing plate 21 is further connected with the negative pole post 4, and the first negative pressing plate 21 is surrounded by the second negative pressing plate 22. Specifically, one side of the first negative pressing plate 21 is recessed to form a recess, and the second negative pressing plate 22 is accommodated in the recess. The bottom surface of the recess is a negative pressing plate bottom 211, and the second negative pressing plate 22 is supported on the negative pressing plate bottom 211 in the recess, so that the negative pressing plate 2 forms an inlaid copper-aluminum composite pressing plate. The first negative pressing plate 21 and the second negative pressing plate 22 are made of different materials. The first negative pressing plate 21 is made of copper, and the second negative pressing plate 22 is made of aluminum. The negative pole post 4 is made of copper, and the first negative pressing plate 21 is connected with the negative pole post 4 by welding, thereby sealing the negative pole post 4. The negative pressing plate 2 adopts an inlaid copper-aluminum composite pressing plate, the first negative pressing plate 21 is connected with the negative pole post 4 for sealing, and the second negative pressing plate 22 can support the PACK welding and play a role in discharging the overcurrent.

[0043] In combination with Fig. 1, the new lithium ion battery structure further includes an insulating sealing member 5, a stop frame 7 and a shell (not shown in the figure). The insulating sealing member 5 is located between the substrate 6 and the pole post, so as to insulate and seal between the substrate 6 and the pole post.

[0044] In one case, the substrate 6, the pole post and the insulating sealing member 5 are connected together by integrated molding. For example, the substrate 6, the pole post and the insulating sealing member 5 are integrally molded by injection molding, which can improve the structural strength of the cover plate assembly.

[0045] The assembling mode of the novel lithium ion battery structure in the scheme is that the winding core is stacked to form, then the winding core is pasted with glue and wrapped with an insulating bag, the tab is divided into two tab clusters, the tab clusters pass through two through holes on the pole and are bent to the pole platform to be welded with the pole platform, the positive pressure plate 1 is welded and sealed with the positive pole 3, and the negative pressure plate 2 is welded and sealed with the negative pole 4, and finally the winding core is loaded into the shell.

[0046] The novel lithium ion battery structure provided in the embodiment divides the tab into a tab cluster, bends the tab cluster, and makes the tab cluster pass through the pole and be bent to the pole platform to be welded and connected with the pole platform, thereby reducing the space occupied by the thick tab bending and solving the problem of difficult thick tab bending. Meanwhile, the connecting sheet structure is cancelled, the tab is directly connected with the pole, the physical impedance of the battery is greatly reduced, and the overcurrent capacity of the winding core is improved.

[0047] Embodiment 2

[0048] In the embodiment, the tab 8 of the novel lithium ion battery structure includes a positive tab and a negative tab, and the positive tab and the negative tab are located on opposite sides of the winding core. The other components and settings in the novel lithium ion battery structure in the embodiment are consistent with those in the embodiment 1.

[0049] In other embodiments, the novel lithium ion battery structure in the embodiment is not only suitable for square batteries, but also suitable for cylindrical batteries.

[0050] The terms "mount", "set", "provided with", and "connected" should be understood in a broad sense. For example, it can be fixed connection, detachable connection, or integral structure; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through an intermediate medium, or internal communication between two devices, elements or components. Those skilled in the art can understand the specific meaning of the above terms in the present application according to the specific circumstances.

[0051] The above describes the present application and its embodiments in a schematic manner, which is not restrictive, and the embodiments shown in the drawings are only one of the embodiments of the present application, and the actual structure is not limited thereto. Therefore, if a person skilled in the art is inspired by the above description, without departing from the creative purpose of the present application, similar structural modes and embodiments can be designed without creativity, which should also belong to the protection scope of the present application.

Claims

1. A novel lithium-ion battery structure, characterized by: The battery cell includes a cover plate assembly and a cell core, The cell core includes a winding core and a tab (8) connected to the winding core, each of the tabs (8) is divided into at least one tab cluster; The cover plate assembly includes a base plate (6) and a pole post; At least one through hole is formed on the pole post; The cell core is located on the inner side of the base plate (6), the tab cluster is passed through the through hole on the pole post from the inner side of the pole post to the outer side of the pole post, and is bent to the pole post platform (33) of the pole post to be directly connected to the pole post.

2. The novel lithium-ion battery structure according to claim 1, characterized in that: The tab (8) includes a positive tab and a negative tab, and the positive tab and the negative tab are located on the same side of the winding core.

3. The novel lithium-ion battery structure according to claim 1, wherein: The tab (8) includes a positive tab and a negative tab, and the positive tab and the negative tab are located on the opposite sides of the winding core, respectively.

4. The novel lithium-ion battery structure according to claim 2 or 3, characterized in that: The pole post includes a positive pole post (3) and a negative pole post (4), and the positive pole post (3) has a first through hole (31) and a second through hole (32) formed at the pole post platform (33); The structure of the negative pole post (4) is consistent with that of the positive pole post (3).

5. The novel lithium-ion battery structure according to claim 4, characterized in that: The cover plate assembly further includes a pressing plate, and the pressing plate includes a positive pressing plate (1) and a negative pressing plate (2); the positive pressing plate (1) is located on the outer side of the positive pole post (3), and the negative pressing plate (2) is located on the outer side of the negative pole post (4).

6. The novel lithium-ion battery structure of claim 5, wherein: The outer side of the positive pole post (3) is provided with a pole post step (34) at the connection position with the positive pressing plate (1), and the edge of the positive pressing plate (1) is connected with the pole post step (34); The connection mode of the negative pole post (4) and the negative pressing plate (2) is consistent with that of the positive pole post (3) and the positive pressing plate (1).

7. The novel lithium-ion battery structure of claim 5, wherein: The negative pressing plate (2) is a composite pressing plate, and the negative pressing plate (2) includes a first negative pressing plate (21) and a second negative pressing plate (22) connected together; The first negative pressing plate (21) is further connected with the negative pole post (4), and the first negative pressing plate (21) is surrounded by the second negative pressing plate (22).

8. The novel lithium-ion battery structure of claim 7, wherein: One side of the first negative pressing plate (21) is recessed to form a groove, and the second negative pressing plate (22) is accommodated in the groove.

9. The novel lithium-ion battery structure according to claim 1, wherein: An insulating sealing member (5) is further arranged between the base plate (6) and the pole post.

10. The novel lithium-ion battery structure of claim 9, wherein: The base plate (6), the pole post and the insulating sealing member (5) are connected together by an integrated molding method.

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