Switching piece, battery tab switching structure and lithium battery

Abstract

The utility model provides an adapter piece, battery tab adapter structure and lithium battery relates to battery technical field, the adapter piece includes the adapter piece body, on the adapter piece body is provided with the pole welding area, first tab welding area and second tab welding area along its length direction at interval, the first tab welding area is provided with the pole welding area, the second tab welding area is provided with the pole welding area, the second tab welding area is provided with the pole welding area, the first tab welding area and the second tab welding area. The pole welding area is used for being welded with a pole, and the first tab welding area and the second tab welding area are respectively welded with a tab. The first tab welding area and the second tab welding area are arranged at intervals along the length direction of the adapter piece body, so that the tabs have longer welding width in the width direction of the adapter piece, the welding area of the tabs and the adapter piece is increased, the overcurrent capacity of the tabs is improved, and the charge-discharge capacity of the lithium battery is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a connecting piece, a battery tab connecting structure and a lithium battery. Background Technique

[0002] In the existing lithium battery structure, both power batteries and energy storage batteries have overcurrent requirements. The higher the overcurrent capacity, the less time is used during the charging process. Therefore, the battery overcurrent capacity is an important indicator to measure the battery capacity. In the battery structure, the weakest link in terms of overcurrent capacity is the tab overcurrent capacity. Improving the tab overcurrent capacity plays a crucial role in improving the overall battery overcurrent capacity.

[0003] Among them, the tab overcurrent capacity is related to the cross-sectional area of the tab. However, since the thickness of the tab group is a fixed value, only by increasing the cross-sectional length of the tab can the tab overcurrent capacity be improved. At present, in the tab connecting structure of lithium batteries, the tab connecting area and the terminal post connecting area in the connecting piece are arranged in a Y shape, resulting in an insufficient effective welding length between the connecting piece and the tab and a small overcurrent area, so that the tab overcurrent capacity cannot be improved. Content of the Utility Model

[0004] In view of this, the utility model provides a connecting piece, a battery tab connecting structure and a lithium battery to solve the problem of insufficient tab overcurrent capacity in the existing battery tab connecting structure.

[0005] The technical solution of the utility model is realized as follows:

[0006] In the first aspect, the utility model provides a connecting piece, including a connecting piece body. Along the length direction of the connecting piece body, a terminal post welding area, a first tab welding area and a second tab welding area are spaced apart. The terminal post welding area is used for welding with a terminal post, and the first tab welding area and the second tab welding area are respectively welded with tabs.

[0007] In the second aspect, the utility model provides a battery tab connecting structure, including a cover plate, two core packages and the connecting piece described in the first aspect. A terminal post is arranged on the cover plate, and tabs are arranged on the core packages. The tabs with the same polarity on the two core packages are respectively welded with the first tab welding area and the second tab welding area, and the terminal post is welded with the terminal post welding area.

[0008] On the basis of the above technical solution, preferably, a positioning groove matching with the terminal post is arranged on one side of the connecting piece body away from the terminal post welding area.

[0009] Based on the above technical solution, preferably, the cover plate further includes a light aluminum plate and a lower plastic part fixedly arranged on the bottom surface of the light aluminum plate. The pole column is insulated and fixedly connected to the light aluminum plate. The adapter plate is arranged on the side of the lower plastic part away from the light aluminum plate. The pole column passes through the lower plastic part and is connected to the positioning groove. The lower plastic part is provided with positioning posts, and positioning holes matching the positioning posts are formed on the adapter plate body.

[0010] Based on the above technical solution, preferably, the distance between the welding area of the pole column, the welding area of the first pole ear and the welding area of the second pole ear is 1 mm to 5 mm.

[0011] In a third aspect, the present utility model provides a lithium battery, including a housing and the battery pole ear adapter structure described in the second aspect. The core package is arranged in the housing, and the cover plate is fixedly connected to the open end of the housing.

[0012] Based on the above technical solution, preferably, the housing includes an outer shell having a receiving space with an open top. An inner shell is arranged in the middle of the receiving space along the length direction of the outer shell. Both ends of the inner shell are fixedly connected to the inner wall of the receiving space. The inner shell has a hollow channel penetrating the outer shell. The inner shell divides the receiving space into two receiving cavities for installing the core package along the width direction of the outer shell.

[0013] Furthermore, preferably, there is a gap between the inner shell and the bottom surface of the receiving space for communicating the two receiving cavities with each other.

[0014] Furthermore, preferably, a plurality of partition plates are vertically arranged at equal intervals along the length direction of the outer shell inside the hollow channel. The partition plates are perpendicularly and fixedly connected to the inner wall of the hollow channel. A plurality of through holes are arranged at equal intervals along the height direction of the partition plates.

[0015] The present utility model has the following beneficial effects compared with the prior art:

[0016] (1) By arranging the welding area of the first pole ear and the welding area of the second pole ear at intervals along the length direction of the adapter plate body, the pole ear can have a longer welding width in the width direction of the adapter plate, thereby increasing the welding area between the pole ear and the adapter plate, enhancing the current-carrying capacity of the pole ear. At the same time, the increase in the welding area also improves the structural strength after the connection between the pole ear and the adapter plate.

[0017] (2) By setting up the inner shell, the accommodating space is divided into two accommodating cavities, creating an isolation structure between the two core packages. The hollow channel design of the inner shell can be used as a cooling channel, allowing coolant or cooling air to pass through, thereby effectively discharging the heat generated inside the battery, helping to evenly disperse the heat, reducing the temperature inside the battery, preventing overheating and thermal runaway phenomena, and greatly improving the heat transfer performance. In a low-temperature environment, through the setting of the hollow channel, it can be used to guide the heat of the heating element into the battery, improving the temperature rise efficiency of the battery in a low-temperature environment, reducing the lithium plating phenomenon, and avoiding the formation of lithium dendrites, thus improving the low-temperature performance and safety of the battery.

[0018] (3) By setting up the partition plate, the structural strength of the inner shell can be improved, preventing the two surfaces of the hollow channel from deforming under the force caused by the expansion of the core package during charging and discharging. At the same time, it can also prevent deformation caused by external impact or vibration, thereby improving the overall strength and stability of the battery housing. The partition plate is provided with a plurality of through holes at equal intervals along its height direction, which can promote the flow of the heat exchange medium (such as air or coolant) in the hollow channel. Through the uniformly distributed through holes, the heat exchange medium can more effectively exchange heat with the inside of the battery, improving the heat exchange effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0020] Figure 1 It is a three-dimensional structure schematic diagram of the adapter plate disclosed by the present invention;

[0021] Figure 2 It is a three-dimensional structure schematic diagram of the battery tab adapter structure disclosed by the present invention;

[0022] Figure 3 It is an assembly structure schematic diagram of the cover plate and the adapter plate disclosed by the present invention;

[0023] Figure 4 It is a plan view of a structural form of the battery tab adapter structure disclosed by the present invention;

[0024] Figure 5 It is a plan view of another structural form of the battery tab adapter structure disclosed by the present invention;

[0025] Figure 6 It is an exploded view of the lithium battery disclosed by the present invention;

[0026] Figure 7 Schematic perspective view of the housing disclosed by the present utility model;

[0027] Figure 8 Top view of the housing disclosed by the present utility model;

[0028] Figure 9 is Figure 8 Cross-sectional view of the plane at A-A in

[0029] Figure 10 is Figure 8 Cross-sectional view of the plane at B-B in

[0030] Reference numerals:

[0031] 1. Adapter plate; 11. Adapter plate body; 12. Pole welding area; 13. First tab welding area; 14. Second tab welding area; 2. Cover plate; 3. Core package; 31. Tab; 15. Positioning groove; 21. Light aluminum plate; 22. Lower plastic part; 23. Pole; 221. Positioning post; 16. Positioning hole; 4. Housing; 41. Outer shell; 411. Accommodating space; 411a. Receiving cavity; 42. Inner shell; 421. Hollow channel; 43. Partition; 431. Through hole. Specific embodiments

[0032] The following will describe clearly and completely the technical solutions in the embodiments of the present utility model in conjunction with the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0033] Embodiment 1

[0034] Embodiment 1 of the present utility model discloses an adapter plate 1. As Figure 1 shown, the adapter plate 1 includes an adapter plate body 11. Along its length direction, a pole welding area 12, a first tab welding area 13 and a second tab welding area 14 are spaced apart on the adapter plate body 11. The pole welding area 12 is used for welding with the pole 23, and the first tab welding area 13 and the second tab welding area 14 are respectively welded with the tab 31.

[0035] By separately setting the first tab welding area and the second tab welding area, the adapter tab 1 provides a larger welding surface area. This structural setting can improve the current-carrying capacity of the tab 31, increase the contact area with the tab 31, and thereby enhance the current conduction efficiency of the tab 31. Compared with the adapter tab of the traditional Y-shaped structure, the adapter tab 1 of this embodiment has a larger welding length, directly solving the problem of insufficient welding length between the adapter tab 1 and the tab 31, and thus improving the current-carrying capacity.

[0036] Embodiment 2

[0037] An embodiment of the present utility model discloses a battery tab adapter structure. Referring to the attached Figures 2 - 5 as shown, it includes a cover plate 2, two core packages 3, and the adapter tab 1 in Embodiment 1. A pole column 23 is provided on the cover plate 2, and a tab 31 is provided on the core package 3. The tabs 31 of the same polarity on the two core packages 3 are respectively welded to the first tab welding area 13 and the second tab welding area 14, and the pole column 23 is welded to the pole column welding area 12.

[0038] Since the first tab welding area 13 and the second tab welding area 14 are spaced along the length direction of the adapter tab body 11, compared with the adapter tab structure of the Y-shaped structure, the welding structure of the adapter tab 1 and the tab 31 in this embodiment can make the tab 31 have a longer welding width in the width direction of the adapter tab 1, thereby increasing the welding area between the tab 31 and the adapter tab 1, increasing the current-carrying capacity of the tab 31, and at the same time, the increase in the welding area also improves the structural strength after the tab 31 and the adapter tab 1 are connected.

[0039] As some preferred embodiments, a positioning groove 15 matching with the pole column 23 is provided on the surface of the adapter tab body 11 away from the pole column welding area 12. With this setting, after the tabs 31 on the two core packages 3 and the adapter tab 1 are welded, the core package 3 and the adapter tab 1 are integrally placed on the cover plate 2, and the position can be located through the positioning groove 15 on the adapter tab 1 and the pole column 23, which is convenient for welding the pole column welding area 12 on the adapter tab 1 and the pole column 23, and reducing the welding quality problems caused by position deviation.

[0040] In this embodiment, the cover plate 2 further includes a light aluminum plate 21 and a lower plastic part 22 fixedly arranged on the bottom surface of the light aluminum plate 21. The lower plastic part 22 is used to establish electrical isolation between the core package 3 and the light aluminum plate 21. The pole column 23 is fixedly connected to the light aluminum plate 21 in an insulated manner. The adapter plate 1 is arranged on the side of the lower plastic part 22 away from the light aluminum plate 21. The pole column 23 passes through the lower plastic part 22 and is connected to the positioning groove 15. The lower plastic part 22 is provided with a positioning post 221, and a positioning hole 16 matching the positioning post 221 is formed on the adapter plate body 11. Through the design of the positioning post 221 and the positioning hole 16, the installation of the adapter plate 1 is more stable, reducing possible displacement or loosening. This structure not only provides accurate alignment during the assembly process but also enhances the mechanical stability of the overall system during use.

[0041] Preferably, the distance between the pole column welding area 12, the first pole ear welding area 13, and the second pole ear welding area 14 is 1 mm to 5 mm. By setting a certain interval between each welding area, the mutual influence of the pole ears 31 caused by overheating during the welding process can be avoided.

[0042] In the above embodiment, the two core packages 3 and the adapter plate 1 adopt the pole ear 31 staggered welding method. Specifically, it is set that the two core packages 3 are respectively the first core package and the second core package. The first core package is provided with a first positive pole ear and a first negative pole ear, and the second core package is provided with a second positive pole ear and a second negative pole ear.

[0043] Refer to the appendix Figure 4 As shown, one of the welding methods is: the first positive pole ear and the first negative pole ear are respectively welded to the first pole ear welding areas 13 on the two adapter plates 1, and the second positive pole ear and the second negative pole ear are respectively welded to the second pole ear welding areas 14 on the two adapter plates 1.

[0044] Refer to the appendix Figure 5 As shown, the other welding method is: the first positive pole ear is welded to the first pole ear welding area on one of the adapter plates 1, the second positive pole ear is welded to the second pole ear welding area on this adapter plate 1, the first negative pole ear is welded to the second pole ear welding area 14 on the other adapter plate 1, and the second negative pole ear is welded to the first pole ear welding area 13 on this adapter plate 1.

[0045] Embodiment Three

[0046] The embodiment of the present utility model also discloses a lithium battery. Refer to the appendix Figure 6 As shown, it includes a housing 4 and the battery pole ear adapter structure in Embodiment Two. The core package 3 is arranged in the housing 4, and the cover plate 2 is fixedly connected to the open end of the housing 4.

[0047] The lithium battery disclosed in this embodiment, by adopting the battery tab transfer structure in Embodiment 2, enables the battery to have stronger overcurrent capacity and improves the charge and discharge capacity of the lithium battery.

[0048] The lithium battery disclosed in this embodiment is a square aluminum shell battery. In order to adapt to high-rate charge and discharge, the core package 3 is designed to be thicker, and the thickness of the housing 4 also increases accordingly. However, with the increase in the battery thickness, the prior art faces the following several significant disadvantages: 1. Heat conduction problem: The greater the battery thickness, the lower the heat conduction efficiency. Whether using air cooling or liquid cooling methods, it is difficult to effectively dissipate the heat inside the battery cells. During high-rate charge and discharge, the generated heat will further exacerbate this problem, resulting in an increase in the internal temperature of the battery, shortening of the cycle life, and even potential safety hazards such as thermal runaway. 2. Low-temperature performance problem: In a low-temperature environment, the heat transfer efficiency of surface heating of the battery is low, and the internal temperature rises slowly. During the charging process, insufficient internal temperature is likely to cause lithium plating phenomenon, and the lithium dendrites formed by long-term accumulation may pierce the separator, leading to battery short circuit and thus triggering serious safety problems.

[0049] Therefore, this embodiment improves the housing 4 to solve the above technical problems.

[0050] Refer to the attached Figures 7 - 10 As shown, the housing 4 of this embodiment includes an outer shell 41. The outer shell 41 has a receiving space 411 with an open top. In the middle of the receiving space 411, an inner shell 42 is arranged along the length direction of the outer shell 41. Both ends of the inner shell 42 are fixedly connected to the inner wall of the receiving space 411. The inner shell 42 has a hollow channel 421 that penetrates the outer shell 41. The inner shell 42 divides the receiving space 411 into two receiving cavities 411 for installing the core package 3 along the width direction of the outer shell 41.

[0051] Adopting the above technical solution, through the setting of the inner shell 42, the receiving space 411 is divided into two receiving cavities 411. First, there is an isolation structure between the two core packages 3. The design of the hollow channel 421 of the inner shell 42 can be used as a cooling channel to allow coolant or cooling air to pass through, thereby effectively discharging the heat generated inside the battery, helping to evenly disperse the heat, reducing the internal temperature of the battery, preventing overheating and thermal runaway phenomena, and greatly improving the heat transfer performance. In a low-temperature environment, through the setting of the hollow channel 421, it can be used to guide the heat of the heating element into the battery internal, improving the temperature rise efficiency of the battery in a low-temperature environment, reducing the lithium plating phenomenon, and avoiding the formation of lithium dendrites, thereby improving the low-temperature performance and safety of the battery.

[0052] As some preferred embodiments, there is a gap between the inner shell 42 and the bottom surface of the accommodating space 411, which is used to enable the first communication between the two accommodating cavities 411. With this setting, the electrolyte can flow between the two accommodating cavities 411, ensuring that the electrolyte can evenly infiltrate the two core packages 3.

[0053] As some preferred embodiments, a plurality of partition plates 43 are vertically arranged at equal intervals along the length direction of the outer shell 41 inside the hollow channel 421. The partition plates 43 are fixedly connected perpendicular to the inner wall of the hollow channel 421. Through the arrangement of the partition plates 43, the structural strength of the inner shell 42 can be improved, preventing the two surfaces of the hollow channel 421 from deforming due to the expansion of the core package 3 during charge and discharge. At the same time, it also prevents deformation caused by external impact or vibration, thereby improving the overall strength and stability of the battery housing 4. A plurality of through holes 431 are arranged at equal intervals along the height direction of the partition plate 43, which can promote the flow of the cooling medium (such as air or coolant) in the hollow channel 421. Through the uniformly distributed through holes 431, the cooling medium can more effectively exchange heat with the inside of the battery, improving the heat exchange effect.

[0054] For the square lithium battery with the battery housing 4 having the above structure, the two core packages 3 are separated by the inner shell 42. The heat of the core package 3 near the middle of the housing 4 can be released in time through the hollow channel 421. At the same time, the design of the hollow channel 421 of the inner shell 422 can be used as a heat exchange channel to allow the heat exchange medium to pass through, thereby effectively exchanging heat with the core package 3 inside the battery, that is, it can achieve rapid cooling, prevent overheating and thermal runaway, and can also heat the core package 3 to prevent lithium plating during charging due to too low temperature, greatly improving the heat transfer performance.

[0055] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A connecting piece, comprising a connecting piece body (11), characterized in that: On the adapter plate body (11), a pole welding area (12), a first tab welding area (13) and a second tab welding area (14) are arranged at intervals along its length direction. The pole welding area (12) is used for welding with a pole (23), and the first tab welding area (13) and the second tab welding area (14) are respectively welded with tabs (31).

2. A battery tab transfer structure, comprising a cover plate (2), two core packages (3), and the transfer piece (1) described in claim 1, characterized in that: A pole (23) is arranged on the cover plate (2), and tabs (31) are arranged on the core package (3). The tabs (31) of the same polarity on two core packages (3) are respectively welded with the first tab welding area (13) and the second tab welding area (14), and the pole (23) is welded with the pole welding area (12).

3. The battery tab transfer structure according to claim 2, wherein: On one side of the adapter plate body (11) away from the pole welding area (12), a positioning groove (15) matched with the pole (23) is arranged.

4. The battery tab transfer structure according to claim 3, wherein: The cover plate (2) further includes a light aluminum plate (21) and a lower plastic part (22) fixedly arranged on the bottom surface of the light aluminum plate (21). The pole (23) is fixedly connected with the light aluminum plate (21) in an insulating manner. The adapter plate (1) is arranged on one side of the lower plastic part (22) away from the light aluminum plate (21). The pole (23) passes through the lower plastic part (22) and is connected with the positioning groove (15). A positioning post (221) is arranged on the lower plastic part (22), and a positioning hole (16) matched with the positioning post (221) is arranged on the adapter plate body (11).

5. The battery tab transfer structure according to claim 2, wherein: The distance between the pole welding area (12), the first tab welding area (13) and the second tab welding area (14) is 1 mm to 5 mm.

6. A lithium battery, comprising a housing (4) and the battery tab transfer structure according to any one of claims 2 to 5, characterized in that: The core package (3) is arranged in a housing (4), and the cover plate (2) is fixedly connected with the open end of the housing (4).

7. The lithium battery according to claim 6, characterized in that, The housing (4) includes an outer shell (41). The outer shell (41) has a receiving space (411) with an open top. An inner shell (42) is arranged in the middle of the receiving space (411) along the length direction of the outer shell (41). Two ends of the inner shell (42) are respectively fixedly connected with the inner wall of the receiving space (411). The inner shell (42) has a hollow channel (421) penetrating through the outer shell (41). The inner shell (42) divides the receiving space (411) into two receiving cavities (411a) for installing the core package (3) along the width direction of the outer shell (41).

8. The lithium battery according to claim 7, wherein There is a gap between the inner shell (42) and the bottom surface of the receiving space (411) for communicating the two receiving cavities (411a) with each other.

9. The lithium battery according to claim 7, wherein, Inside the hollow channel (421), a plurality of partition plates (43) are vertically arranged at equal intervals along the length direction of the outer shell (41). The partition plates (43) are fixedly connected with the inner wall of the hollow channel (421) perpendicularly. A plurality of through holes (431) are arranged at equal intervals along the height direction of the partition plates (43).

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