Busbar with battery cell expansion self-adjusting function and battery cell module thereof
By adopting eight-shaped expansion absorption units and multiple arc-shaped boss structures in the busbar, the bus discharge desoldering problem caused by cell expansion is solved, the safety and service life of the battery cell module are improved, and the different battery cells are adapted to expansion characteristics.
Patent Information
- Application Number
- CN202420943938.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-30
- Publication Date
- 2025-01-10
- Estimated Expiration
- 2034-04-30
AI Technical Summary
The existing busbar structure cannot be effectively buffered during the expansion of the battery cell, resulting in desoldering of the welding position with the battery cell pole, posing a safety hazard.
Design a busbar with self-regulation function of cell expansion, adopts eight-shaped expansion absorption units and multiple arc-shaped boss structures to provide buffer space and uniform distribution of deformation stress, ensuring the welding stability of busbar and cell pole column .
It effectively avoids bus discharge and desoldering caused by cell expansion, improves the safety and reliability of the PACK system, extends the service life, and is suitable for the expansion rate and amplitude of different cell cells.
Smart Images
Figure CN222338445U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of power batteries, and in particular to a busbar with a self-regulating function for battery cell expansion and a battery cell module thereof. Background Art
[0002] As energy and environmental issues become increasingly severe, countries around the world are stepping up their efforts in the research and development of new energy vehicles. As an important component of electric vehicles, power batteries are imperative for their research and development.
[0003] In the current PACK system, the cells are usually grouped by connecting the cells in series or in parallel via a bus bar welded on the cell tabs to achieve the desired grouping method.
[0004] In the current busbar design, the busbar is usually designed as a "flat structure" or a "single boss structure". However, since the battery cell will expand in the width direction after a certain period of use, the distance between adjacent battery cells in the module becomes larger.
[0005] At this time, since the busbar with a "flat structure" has no buffer space, it will generate a pulling force on the welding position between the busbar and the battery pole during the expansion of the battery cell, causing desoldering between the busbar and the battery pole, thereby causing a safety hazard; similarly, since the expansion direction of the battery cell is the width direction, the expansion in the middle of the battery cell will be greater towards the back, while the expansion range at both ends of the battery cell is smaller. The busbar with a "single boss structure" will also cause desoldering between the busbar and the battery pole during the expansion of the battery cell, thereby causing a safety hazard.
[0006] Therefore, the existing busbar structures cannot avoid the desoldering between the busbar and the battery cell due to the expansion of the battery cell. In view of the above problem, the applicant has conducted research and designed a busbar with a self-regulating function for battery cell expansion. Utility Model Content
[0007] The utility model aims to provide a busbar and a battery cell module with a self-regulating function for battery cell expansion, so as to solve the problem that the existing busbar structure cannot avoid the desoldering of the busbar and the battery cell due to the battery cell expansion.
[0008] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme: a bus with a self-regulating function for battery cell expansion, comprising a bus body, wherein a first mounting portion and a second mounting portion cooperating with the battery cell poles are symmetrically provided at both ends of the bus body, and at least one group of expansion absorbing units is provided between the first mounting portion and the second mounting portion, and each group of the expansion absorbing units comprises two symmetrically distributed bosses, the cross-section of the bosses is arched, the two bosses form an eight-shaped structure, and the upper and lower surfaces of each of the bosses include multiple arc surfaces.
[0009] The principles and advantages of this solution are:
[0010] 1. In actual application, in this solution, at least one group of expansion absorbing units is provided between the first mounting portion and the second mounting portion, and the two bosses in the expansion absorbing unit are distributed in an eight-shaped structure. When the battery cell continues to expand, the expansion absorbing unit expands along the opening direction of the eight-shaped structure, so that the bus as a whole has a larger deformation buffer space to prevent desoldering between the battery cell poles; secondly, multiple groups of expansion absorbing units make the stress distribution of the bus more uniform when it is deformed, and when one group of expansion units fails, the other groups can continue to play a role to maintain the overall stability of the module; at the same time, multiple groups of expansion absorbing units enable the bus to be suitable for a variety of different battery cells that may have differences in expansion rate and amplitude during the charging and discharging process, making the bus more applicable.
[0011] 2. The upper and lower surfaces of the boss of the expansion absorbing unit of the present scheme include multiple arc surfaces. Compared with the single arc boss structure in the prior art, the multi-arc structure makes the boss more flexible, and each arc surface can independently and slightly adjust its shape to adapt to expansion. As a whole, the boss shows greater adaptability and durability in dealing with expansion deformation; and the multi-arc structure gives the expansion absorbing unit as a whole more deformation space. When the battery cell expands, the joints or transition zones between the arc surfaces can accommodate a certain displacement, unlike the single arc structure, where all expansion displacements must be completed on a continuous arc surface. This helps to reduce the internal stress caused by expansion, increase the reliability of the bus, and greatly reduce the safety accidents caused by desoldering of the power battery.
[0012] Furthermore, the first mounting portion and the second mounting portion are positioning holes.
[0013] The positioning holes in the above arrangement are used to cooperate with the battery cell poles, which is conducive to rapid positioning of the busbar during installation, while improving the accuracy of the installation position and improving the installation quality and efficiency of the busbar.
[0014] Furthermore, the busbar body is provided with an adjusting countersunk hole on one side of the boss protruding with the positioning hole as the center, and the adjusting countersunk hole is connected with the positioning hole.
[0015] The above arrangement ensures that when the busbar is welded to the pole, all the solder is located in the adjusting countersunk hole and will not overflow randomly, thereby ensuring that the welding point structure is neat; at the same time, the countersunk hole is adjusted so that the surface of the welding point is flush with the surface of the busbar body, so that the remaining surfaces of the busbar except the expansion absorption unit are flush, thereby ensuring the overall flatness of the busbar.
[0016] Furthermore, the expansion absorption unit is located between two adjacent adjusting sink holes.
[0017] The purpose of the above arrangement is to ensure that the relative position between the positioning hole and the battery cell remains unchanged when the expansion absorption unit absorbs the expansion deformation of the battery cell, thereby preventing the busbar and the battery cell pole from being desoldered.
[0018] Furthermore, a plurality of groups of the expansion absorption units are evenly arranged along the length direction of the busbar.
[0019] The above arrangement enables multiple groups of expansion absorption units to simultaneously absorb the volume changes generated during the charging and discharging of the battery cells at different locations on the bus, making the stress more evenly distributed on the bus, reducing local stress concentration, and reducing material fatigue and potential structural failure risks.
[0020] Furthermore, a plurality of groups of the expansion absorption units are nested in sequence in the figure-eight structure.
[0021] The above-mentioned arrangement can realize the step-by-step absorption and dispersion of the expansion of the battery cell. When the battery cell expands, the innermost expansion absorption unit compensates first. As the expansion amount increases, the outer expansion absorption units intervene in turn to form a multi-level buffer, which effectively reduces the burden of a single structure, improves the overall absorption efficiency, reduces fatigue damage of the material, and extends the service life of the bus and the entire battery module.
[0022] The utility model also provides a technical solution: a battery cell module with a self-regulating function of battery cell expansion, comprising a plurality of battery cells and a bus bar, wherein the battery cells are arranged along the expansion direction and connected by the bus bar.
[0023] The principles and advantages of this solution are:
[0024] In actual application, the battery cells are arranged along the expansion direction and connected by the busbar, so that no matter the battery cells are connected in series or in parallel, the busbar can absorb the deformation of the battery cells along the expansion direction, ensuring the stability of the welding structure between the busbar and the battery cell poles, greatly improving the safety and reliability of the PACK system.
[0025] Furthermore, the opening of the figure eight structure of the busbar faces the interior of the battery cell.
[0026] When the battery cell expands, the opening of the figure-eight structure of the bus expands in the direction of expansion until it is deformed into a closed opening of the figure-eight structure, so that there is sufficient buffer space in the welding structure between the battery cell and the bus, effectively avoiding desoldering caused by expansion tension.
[0027] Furthermore, the positioning holes of the busbar match with the battery cell poles.
[0028] The above arrangement enables the installation position of the busbar to be determined quickly and accurately when the busbar and the battery cell are connected, which greatly improves production efficiency and production quality. BRIEF DESCRIPTION OF THE DRAWINGS
[0029] Figure 1 It is a schematic diagram of the structure of the bus bar of the first embodiment of the utility model.
[0030] Figure 2 It is a schematic diagram of the upper surface of the busbar of the first embodiment of the utility model.
[0031] Figure 3 This is a schematic diagram of horizontal arrangement of multiple groups of expansion absorption units according to the first embodiment of the utility model.
[0032] Figure 4 Schematic diagram of nested arrangement of multiple expansion absorption units in Embodiment 2 of the utility model
[0033] Figure 5 This is a schematic diagram of a structural battery cell module according to the third embodiment of the present invention. DETAILED DESCRIPTION
[0034] The following is further described in detail through specific implementation methods:
[0035] The reference numerals in the drawings of the specification include: battery cell 1, busbar 2, busbar body 21, first mounting portion 22, second mounting portion 23, positioning hole 24, expansion absorbing unit 25, boss 251, plane 2521, arc surface 2522, and adjustment countersunk hole 26.
[0036] Embodiment 1
[0037] A busbar with a self-regulating function for battery cell expansion, such as Figure 1-Figure 3 As shown, the busbar 2 includes a busbar body 21, and a first mounting portion 22 and a second mounting portion 23 that match the battery cell pole are symmetrically provided at both ends of the busbar body 21, and the first mounting portion 22 and the second mounting portion 23 are circular positioning holes 24; at least one group of expansion absorption units 25 is provided between two adjacent positioning holes 24, and each group of expansion units includes two symmetrically distributed bosses 251, and the cross section of the boss 251 is arched, and the two bosses 251 form an eight-shaped structure. The number of expansion absorption units 25 and the angle between the two bosses 251 are determined according to the specifications of the actual battery cell 1. The design is carried out in an inch manner; the upper and lower surfaces of each boss 251 include a plane 2521 located in the middle position and a plurality of arc surfaces 2522 symmetrically distributed on both sides of the plane 2521, and the connections between the surfaces are subjected to arc transition treatment, so as to increase the deformation space of the expansion absorption unit 25 and reduce the internal stress of the bus 2; further, in order to ensure the flatness of the welding point structure between the positioning hole 24 and the battery cell pole, the bus body 21 is provided with a circular adjusting countersunk hole 26 on the raised side of the boss 251 with the positioning hole 24 as the center, and the adjusting countersunk hole 26 is connected to the positioning hole 24.
[0038] like Figure 4As shown, when there are multiple groups of expansion absorption units 25 on the bus 2, the multiple groups of expansion absorption units 25 are evenly arranged along the length direction of the bus 2, and the opening directions of the figure-eight structures of the expansion absorption units 25 are consistent, which is beneficial for the multiple groups of expansion absorption units 25 to simultaneously absorb the volume changes generated during the charging and discharging of the battery cells 1 at different parts of the bus 2, so that the stress is more evenly distributed on the bus 2, reducing local stress concentration, and reducing material fatigue and potential structural failure risks.
[0039] Embodiment 2
[0040] The difference between this embodiment and the first embodiment is that: Figure 4 As shown, the two groups of expansion absorption units 25 on the bus 2 are nested, and the outermost group of expansion absorption units 25 is nested with another group of expansion absorption units 25 in the figure-eight structure, which is conducive to realizing step-by-step absorption of expansion, forming a multi-level buffer, effectively reducing the burden of a single structure, and improving the overall absorption efficiency.
[0041] Embodiment 3
[0042] A battery cell module having a self-regulating function for battery cell expansion, such as Figure 5 As shown, it includes a plurality of battery cells 1 and a bus 2 connecting the battery cells 1, and the plurality of battery cells 1 are arranged along the width direction thereof; the bus 2 is arranged along the width direction of the battery cells 1, and the opening of the figure-eight structure of the bus 2 faces the inside of the battery cells 1, so that the battery cells 1 can expand and absorb 25 units along the opening of the figure-eight structure to expand.
[0043] The specific implementation process is as follows:
[0044] When connected in series:
[0045] Arrange multiple battery cells 1 along their width direction, with the positive and negative poles of adjacent battery cells 1 arranged alternately, then align the positioning holes 24 of the bus 2 with the poles of the battery cell 1, and make the opening of the figure-eight structure of the expansion absorption unit 25 face the inside of the battery cell 1, then weld and fix the bus 2 to the poles of the battery cell 1 to form a battery cell module.
[0046] When connected in parallel:
[0047] Arrange multiple battery cells 1 along their width direction with the positive poles of the battery cells 1 on one side, then align the positioning holes 24 of the busbar 2 with the poles of the battery cells 1, and make the opening of the figure-eight structure of the expansion absorption unit 25 face the inside of the battery cell 1, then weld and fix the busbar 2 to the poles of the battery cells 1 to form a battery cell module.
[0048] The above is only an embodiment of the utility model, and the common knowledge such as the known specific technical solutions and / or characteristics in the solution is not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the utility model, several deformations and improvements can be made, which should also be regarded as the protection scope of the utility model, and these will not affect the effect of the implementation of the utility model and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.
Claims
1. A busbar with a self-regulating function for battery cell expansion, characterized in that: It includes a busbar body, wherein a first mounting portion and a second mounting portion cooperating with the battery cell poles are symmetrically provided at both ends of the busbar body, at least one group of expansion absorbing units is provided between the first mounting portion and the second mounting portion, and each group of the expansion absorbing units includes two symmetrically distributed bosses, the cross-section of the bosses is arched, the two bosses form an eight-shaped structure, and the upper and lower surfaces of each boss include multiple arc surfaces.
2. A busbar with a self-regulating function for battery cell expansion according to claim 1, characterized in that: The first mounting portion and the second mounting portion are positioning holes.
3. A busbar with a self-regulating function for battery cell expansion according to claim 2, characterized in that: The busbar body is provided with an adjusting countersunk hole on one side of the boss protruding with the positioning hole as the center, and the adjusting countersunk hole is connected with the positioning hole.
4. A busbar with a self-regulating function for battery cell expansion according to claim 3, characterized in that: The expansion absorption unit is located between two adjacent adjusting countersunk holes.
5. A busbar with a self-regulating function for battery cell expansion according to claim 4, characterized in that: The plurality of expansion absorption units are evenly arranged along the length direction of the busbar.
6. A busbar with a self-regulating function for battery cell expansion according to claim 4, characterized in that: A plurality of groups of the expansion absorption units are nested in the figure-eight structure in sequence.
7. A battery cell module with a self-regulating function for battery cell expansion, characterized in that: The invention comprises a plurality of battery cells and a busbar as claimed in any one of claims 1 to 6, wherein the battery cells are arranged along the width direction thereof and connected by the busbar.
8. The battery cell module with the battery cell expansion self-regulation function according to claim 7, characterized in that: The opening of the figure eight structure of the busbar faces the inside of the battery cell.
9. The battery cell module with the battery cell expansion self-regulation function according to claim 8, characterized in that: The positioning holes of the busbar match with the battery cell poles.