Voltage equalization tooling for battery cells

Abstract

The application relates to the technical field of batteries, in particular to a voltage equalization tool for battery cells. The tool comprises a bottom box and a cover plate arranged above the bottom box, a plurality of battery cells with positive poles upward and uniformly distributed along the x direction are arranged in the bottom box, a plurality of parallel plates are arranged on the cover plate along the x direction, each parallel plate is provided with one positive probe for elastically contacting the positive pole of the corresponding battery cell and one negative probe for elastically contacting the negative pole of the corresponding battery cell, one positive lead wire is electrically connected to each positive probe, the positive poles of adjacent battery cells are connected in parallel through the first-end-to-last-end connection of the positive lead wire, one negative lead wire is electrically connected to each negative probe, and the negative poles of adjacent battery cells are connected in parallel through the first-end-to-last-end connection of the negative lead wire. The tool can realize parallel voltage equalization processing of multiple battery cells, can process multiple battery cells at the same time, and has greatly improved efficiency compared with traditional single-battery-cell equalization tools.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and more specifically to a voltage balancing fixture for battery cells. Background Technology

[0002] After a battery pack has been used for a certain number of years, differences will gradually appear between the individual cells in parameters such as voltage, internal resistance, capacity, self-reliability, and discharge curve. This will cause the battery pack to experience a significant drop in output power, a marked reduction in full-power operating time, a severe decrease in actual discharge capacity, and excessive heat generation during charging and discharging.

[0003] When a battery pack exhibits the above conditions, it is typically no longer usable and needs to be replaced with new batteries. The old battery pack is then recycled. The recycled batteries undergo voltage equalization through charge-discharge adjustments, ensuring that the cells operate at the same rate, thus meeting usage requirements again and allowing for reuse. Existing tooling for charging and discharging cells typically only allows for single-cell charging and discharging, failing to achieve simultaneous voltage adjustment for multiple cells, resulting in low efficiency. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a voltage balancing fixture for battery cells that enables parallel voltage balancing of multiple battery cells. It can process multiple battery cells simultaneously, and its efficiency is greatly improved compared to traditional single-cell balancing fixtures.

[0005] The present invention provides a voltage balancing fixture for battery cells, comprising a base box and a cover plate disposed above the base box. The base box contains a plurality of battery cells with their terminals facing upward and evenly distributed along the x-direction. The cover plate is provided with a plurality of parallel plates along the x-direction. Each battery cell is arranged in a one-to-one correspondence with the parallel plates. Each parallel plate is provided with a positive electrode probe for elastic contact with the positive terminal of the corresponding battery cell and a negative electrode probe for elastic contact with the negative terminal of the corresponding battery cell.

[0006] Each of the positive probes is electrically connected to a positive wire, and the positive terminals of adjacent cells are connected in parallel through positive wires connected end to end;

[0007] Each of the negative electrode probes is electrically connected to a negative electrode wire, and the negative electrode posts of adjacent cells are connected in parallel through negative electrode wires connected end to end;

[0008] The thickness direction of the battery cell is the x-direction, and the width direction of the battery cell is the y-direction.

[0009] Preferably, the inner walls on both sides of the cover plate are provided with gear rolling grooves extending in the x direction, and gears are rotatably provided at both ends of the parallel plate, and the gears are meshed with the gear rolling grooves.

[0010] Preferably, the cover plate is provided with tension springs on both sides, the bottom of which can be connected to the bottom box, and the cover plate is elastically set above the bottom box by the tension springs.

[0011] Preferably, two insulating sliders are slidably disposed on the parallel plate along the y-direction, and the positive electrode probe and the negative electrode probe are respectively disposed on the corresponding insulating sliders.

[0012] Preferably, the parallel plate is provided with a groove extending along the y-direction, and the insulating sliders are all embedded in the groove and slidably engaged with the groove, or

[0013] The parallel plate is provided with two sliding grooves extending along the y direction, and the insulating sliders are respectively embedded in the corresponding sliding grooves and are slidably engaged with the sliding grooves.

[0014] Preferably, the positive / negative probe is disposed vertically on the insulating slider, and an elastic member is sleeved between the positive / negative probe and the bottom of the insulating slider, so that the positive / negative probe can elastically contact the corresponding electrode through the elastic member.

[0015] Preferably, the bottom box is provided with a first limiting member for limiting the battery cell in the x-direction and a second limiting member for limiting the battery cell in the y-direction.

[0016] Preferably, the first limiting component includes a first sliding groove and a first limiting stud. The first sliding groove is an x-direction sliding groove symmetrically arranged on both sides of the bottom box and extending along the x-direction. The first limiting stud penetrates the side wall of the bottom box along the y-direction and is slidably disposed in the x-direction sliding groove. The first limiting stud is provided with hand-tightening screws at both ends. The first limiting stud is limited and engaged with the battery cell along the x-direction.

[0017] The second limiting component includes a second sliding groove and a second limiting stud. The second sliding groove is a y-direction sliding groove symmetrically arranged at both ends of the bottom box and extending along the y direction. The second limiting stud penetrates the two end walls of the bottom box along the x direction and is slidably arranged in the y-direction sliding groove. The second limiting stud is limited and engaged with both sides of the battery cell along the y direction.

[0018] Preferably, one end of the positive / negative conductor is provided with a female connector, and the other end is provided with a male connector that can be plugged into the female connector.

[0019] Preferably, a current-limiting resistor is connected in series with each of the negative electrode wires.

[0020] The beneficial effects of this invention are as follows:

[0021] 1. This device utilizes the principle of consistent voltage across parallel battery cells. It directly places the cells requiring voltage balancing in parallel within the fixture, achieving balanced charging and discharging among the cells. The balancing process for each cell is performed synchronously, significantly improving efficiency compared to traditional single-cell balancing fixtures. Furthermore, the parallel-connected cells can achieve autonomous balancing; as the voltage difference between cells decreases, the current decreases synchronously, resulting in high consistency in voltage differences after balancing. Compared to traditional individual cell balancing, this method is easier to control and offers higher reliability.

[0022] 2. By using a parallel plate that slides with the base box and an insulating slider that slides with the parallel plate, the x and y positions of the probe can be adjusted, making the fixture applicable to cells of different widths and thicknesses, thus improving the fixture's versatility and making it highly adaptable.

[0023] 3. Flexible connections are used between the probe and the insulating slider, and between the cover plate and the base box. This ensures good contact between the probe and the electrode post at different cell heights, guaranteeing the stability of the voltage equalization process and further improving the versatility of the tooling. Limiting components are installed in the x and y directions to limit cell movement during voltage equalization, preventing cell sway and ensuring stable contact between the probe and the electrode post.

[0024] 4. The probe is equipped with conductive positive and negative leads that can be quickly plugged in. The positive and negative leads can be quickly connected in parallel through the male and female connectors, which is simple to operate and more efficient. Attached Figure Description

[0025] Figure 1 This is the front view of the present invention;

[0026] Figure 2 This is the left view of the present invention;

[0027] Figure 3 This is a right view of the present invention;

[0028] Figure 4 This is a top view of the present invention;

[0029] Figure 5 This is a top view of the cover plate of the present invention;

[0030] Figure 6 This is a front view of the cover plate of the present invention;

[0031] Figure 7 This is a top view of the parallel plate of the present invention;

[0032] Figure 8 This is a cross-sectional view of the invention connected in parallel along a horizontal plane;

[0033] Figure 9 This is a schematic diagram of the gear rolling groove of the present invention;

[0034] Figure 10 for Figure 7 Sectional view from direction A1;

[0035] Figure 11 for Figure 7 Sectional view from direction A2;

[0036] Figure 12 This is a schematic diagram of the positive electrode conductor structure;

[0037] Figure 13 This is a schematic diagram of the negative electrode conductor structure;

[0038] Figure 14 This is a schematic diagram of the resistor selection table for the present invention.

[0039] 1-Base box; 2-Cover plate; 3-Battery cell; 4-Positive terminal; 5-Negative terminal; 6-Parallel plate; 7-Positive probe; 8-Negative probe; 9-First slide groove; 10-First limiting stud; 11-Second slide groove; 12-Second limiting stud; 13-Hand screw; 14-Tension spring; 15-Positive wire; 16-Negative wire; 17-Current limiting resistor; 18-Slide groove; 19-Insulated slider; 20-Wire groove; 21-Compression spring; 22-Spring baffle; 23-Gear; 24-Gear rolling groove; 25-Female connector; 26-Male connector; 27-Plug-in slot. Detailed Implementation

[0040] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0041] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0042] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0043] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0044] References to "one embodiment" or "some embodiments" in this specification mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized. "A plurality" means "two or more."

[0045] Example 1

[0046] This embodiment is a preferred embodiment of a voltage balancing fixture for battery cells according to this application. For ease of explanation, only the parts related to this embodiment will be described, as detailed below:

[0047] like Figure 1-4 As shown, a voltage balancing fixture for battery cells includes a base box 1 and a cover plate 2 disposed above the base box 1. Several battery cells 3, with their terminals facing upwards and evenly distributed along the x-direction, are placed inside the base box 1. Multiple parallel plates 6 are disposed on the cover plate 2 along the x-direction. Each battery cell 3 is correspondingly positioned with one of the parallel plates 6. Each parallel plate 6 has a downward-facing positive electrode probe 7 for elastic contact with the positive terminal 4 of the corresponding battery cell 3 and a negative electrode probe 8 for elastic contact with the negative terminal 5 of the corresponding battery cell 3. Each positive electrode probe 7 is conductively connected to a positive electrode wire 15, and adjacent positive terminals 4 of the battery cells 3 are connected in parallel via end-to-end positive electrode wires 15. Each negative electrode probe 8 is conductively connected to a negative electrode wire 16, and adjacent negative terminals 5 of the battery cells 3 are connected in parallel via end-to-end negative electrode wires 16. The thickness direction of the battery cell 3 is the x-direction, and the width direction of the battery cell 3 is the y-direction.

[0048] In one embodiment, the cover plate 2 is provided with tension springs 14 on both sides, the bottom of which can be connected to the base box 1. The cover plate 2 is elastically positioned above the base box 1 by the tension springs 14. The top of the tension spring 14 is fixedly connected to both sides of the cover plate 2, and the bottom is provided with hooks. By engaging with slots or rings provided on the side wall of the base box 1, the cover plate 2 can be elastically fixed to the base box 1. Tension springs 14 can be provided in one set on each side, or multiple sets can be provided on both sides; the specific number can be set according to actual needs.

[0049] In one embodiment, the base box 1 is provided with a first limiting member for limiting the battery cell 3 in the x-direction and a second limiting member for limiting the battery cell 3 in the y-direction. The first limiting member and the second limiting member can be implemented by a slider or a sliding block; any method that can limit the battery cell in the x-direction and y-direction is acceptable.

[0050] In one embodiment, the method is described using a sliding rod. The first limiting member includes a first sliding groove 9 and a first limiting stud 10. The first sliding groove 9 is an x-direction sliding groove symmetrically arranged on both sides of the base box 1 and extending along the x-direction. The first limiting stud 10 penetrates the side wall of the base box 1 along the y-direction and is slidably disposed within the x-direction sliding groove. The first limiting stud 10 has hand-tightening screws 13 at both ends. The first limiting stud 10 and the battery cell 3 are limited and engaged in the x-direction. After the battery cell is assembled, the hand-tightening screws 13 are loosened, the first limiting stud 10 is adjusted to engage with the side of the battery cell, and then the hand-tightening screws 13 are tightened to achieve the x-direction limiting of the battery cell.

[0051] In one embodiment, the method is also described using a sliding rod. The second limiting component includes a second sliding groove 11 and a second limiting stud 12. The second sliding groove 11 is a y-direction sliding groove symmetrically arranged at both ends of the base box 1 and extending along the y-direction. The second limiting stud 12 penetrates both end walls of the base box 1 along the x-direction and is slidably disposed within the y-direction sliding groove. The second limiting stud 12 engages with both sides of the battery cell 3 along the y-direction for limiting. After the battery cell is assembled, the hand screw 13 is loosened, and the two second limiting studs 12 are adjusted to engage with the sides of the battery cell for limiting. Then, the hand screw 13 is tightened, thereby limiting the battery cell between the two second limiting studs 12, thus achieving y-direction limiting of the battery cell.

[0052] In addition to the above implementation methods, a slider can also be used to achieve the limiting position. For example, an x-direction groove extending in the x-direction can be provided at the bottom of the base box 1, and a slider can be slidably set in the x-direction groove. By moving the slider to a suitable position, the limiting engagement between the slider and the battery cell can be achieved, thereby realizing the x-direction limiting of the battery cell. The Y-direction limiting can also be arranged in a similar way. As long as the clamping of both sides of the battery cell can be achieved, it can be adopted.

[0053] In one embodiment, such as Figure 5-9 As shown, the inner walls of both sides of the cover plate 2 are provided with gear rolling grooves 24 extending in the x-direction. Gears 23 are rotatably mounted at both ends of the parallel plate 6, and the gears 23 mesh with the gear rolling grooves 24. By pushing the parallel plate 6, the gears 23 can roll in the gear rolling grooves 24, thereby causing the parallel plate 6 to slide along the gear rolling grooves 24. This ensures that the gap between each parallel plate 6 is adapted to the thickness of the battery cell, thus achieving a one-to-one correspondence between battery cells of different specifications and the parallel plates 6, ensuring good contact between the probe and the electrode. This invention can handle battery cell thicknesses from 26mm to 81mm. The cover plate 2 adopts a three-part design, i.e., one end is open, facilitating the placement and removal of the parallel plates 6 from the open end, correspondingly achieving the adaptation of the number of parallel plates 6 to the number of battery cells.

[0054] In addition to using the meshing of gear rolling groove 24 and gear 23, sliders can be set at both ends of the parallel plate 6, and sliding grooves can be set on the inner walls of both sides of the base box 1. The gap between the parallel plates 6 can be adjusted by the cooperation of the sliders and sliding grooves. Alternatively, slide rails can be set on both sides of the base box 1, and rollers can be set at both ends of the parallel plate 6. The gap between the parallel plates 6 can be adjusted by the cooperation of the rollers and slide rails.

[0055] In one embodiment, two insulating sliders 19 are slidably disposed on the parallel plate 6 along the y-direction, and the positive electrode probe 7 and the negative electrode probe 8 are respectively disposed on the corresponding insulating sliders 19.

[0056] In one embodiment, the parallel plate 6 is provided with a groove 18 extending along the y-direction, and the insulating sliders 19 are all embedded in the groove 18 and slidably engaged with the groove 18. This invention can handle battery cell widths of 148mm to 300mm.

[0057] In one embodiment, the parallel plate 6 is provided with two sliding grooves 18 extending along the y-direction and symmetrical along the centerline of the parallel plate. The insulating sliders 19 are respectively embedded in the corresponding sliding grooves 18 and are slidably engaged with the sliding grooves 18. The insulating sliders 19 are provided with grooves on both sides, which can be fitted with the inner side of the sliding grooves 18 to realize the sliding adjustment of the insulating sliders 19 within the sliding grooves 18.

[0058] In one embodiment, such as Figure 10 , 11As shown, the positive probe 7 and negative probe 8 are vertically connected to the insulating slider 19. A compression spring 21 is fitted between the positive probe 7 / negative probe 8 and the bottom of the insulating slider 19. Spring baffles 22 are also provided at the top and bottom of the positive probe 7 / negative probe 8. The compression spring 21 is compressed between the bottom of the insulating slider 19 and the top of the spring baffle 22. Thus, under the restoring force of the compression spring 21, a downward elastic force is applied to the positive probe 7 / negative probe 8, thereby achieving elastic contact between the positive probe 7 / negative probe 8 and the corresponding electrode post, ensuring good conductive contact. Furthermore, the bottom end of the probe adopts a rounded structure, which increases the contact area with the electrode post, further ensuring contact stability.

[0059] In one embodiment, such as Figure 12 , 13 As shown, one end of the positive wire 15 and the negative wire 16 is provided with a female connector 25, and the other end is provided with a male connector 26 that can be plugged into the female connector 25. In one embodiment, a current-limiting resistor 17 is connected in series with each negative wire 16.

[0060] The female connector 25 has a groove 27 that matches the shape of the male connector 26. The head of the male connector 26 is conical, and the inner wall of the groove 27 also has a matching cone angle. After the battery cells are arranged and each positive probe 7 / negative probe 8 makes conductive contact with its corresponding terminal, the positive and negative terminals of each battery cell are quickly connected in parallel by plugging the male connector 26 and the female connector 25 between adjacent wires. Only one female connector or one male connector is needed for the wires on the parallel connection boards at both ends of the fixture.

[0061] To facilitate the movement of the tooling and ensure good conductivity, the positive probe 7 and the negative probe 8 are both provided with radially penetrating wire grooves 20 on the upper part. The positive wire 15 and the negative wire 16 are both inserted into the wire grooves 20. The conductive connection and fixation between the wires and the probes are achieved by stripping and soldering at the positions corresponding to the wire grooves 20.

[0062] In addition, to facilitate the differentiation between the positive wire 15 and the negative wire 16 during assembly and to achieve a foolproof design, different colors can be used on the insulation sheaths of the positive wire 15 and the negative wire 16, such as red for the positive wire and black for the negative wire.

[0063] The current-limiting resistor 17 connected in series on the negative electrode wire 16 is used to prevent the instantaneous discharge current of the battery cells from being too large after parallel connection, which could cause them to melt. Based on the optimal requirement of limiting the maximum current to 100A, considering that the voltage difference range of the battery cells is generally 5mV to 1.4V (1.4V for ternary lithium batteries and 1.15V for lithium iron phosphate batteries), the resistor is selected as follows: Figure 14As shown. In addition, a corresponding resistor can be selected based on the cell capacity to ensure that the balancing current does not exceed 1C.

[0064] The working process of this device is as follows:

[0065] After the battery cells are installed in the base box, adjust the limit studs in both directions to fix the cell positions. Then, adjust the parallel plate on the cover and the insulating slider on the parallel plate to align the probes with the positive and negative terminals of the battery cells. Next, attach the tension springs on both sides of the fixture to ensure complete contact between each probe and its corresponding cell terminal. By connecting the male and female connectors of adjacent wires, the positive and negative terminals of each cell are quickly connected in parallel. This creates a parallel connection for all the cells in the fixture, which can then be left to stand. When the voltage difference between the cells decreases to a certain range, the current decreases synchronously, achieving overall autonomous balancing among the cells.

[0066] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A voltage balancing fixture for battery cells, characterized in that: Includes a base box (1) and a cover plate (2) disposed above the base box (1). The base box (1) contains a number of battery cells (3) with their terminals facing upward and evenly distributed along the x direction. The cover plate (2) is provided with a number of parallel plates (6) along the x direction. The battery cells (3) are arranged one-to-one with the parallel plates (6). Each parallel plate (6) has a positive electrode probe (7) for elastic contact with the positive terminal (4) of the corresponding battery cell (3) and a negative electrode probe (8) for elastic contact with the negative terminal (5) of the corresponding battery cell (3). Each of the positive probes (7) is electrically connected to a positive wire (15), and the positive posts (4) of adjacent cells (3) are connected in parallel through the positive wires (15) connected end to end; Each of the negative electrode probes (8) is electrically connected to a negative electrode wire (16), and the negative electrode posts (5) of adjacent cells (3) are connected in parallel through the negative electrode wires (16) connected end to end; Among them, the thickness direction of the battery cell (3) is the x direction, and the width direction of the battery cell (3) is the y direction; The inner walls of both sides of the cover plate (2) are provided with gear rolling grooves (24) extending in the x direction. The two ends of the parallel plate (6) are rotatably provided with gears (23), and the gears (23) and the gear rolling grooves (24) are meshed with each other.

2. The voltage balancing fixture for battery cells according to claim 1, characterized in that: The cover plate (2) is provided with tension springs (14) on both sides, which can be connected to the bottom box (1) at the bottom end. The cover plate (2) is elastically set above the bottom box (1) by the tension springs (14).

3. The voltage balancing fixture for battery cells according to claim 1, characterized in that: Two insulating sliders (19) are slidably disposed on the parallel plate (6) along the y direction, and the positive probe (7) and the negative probe (8) are respectively disposed on the corresponding insulating sliders (19).

4. The voltage balancing fixture for battery cells according to claim 3, characterized in that: The parallel plate (6) is provided with a groove (18) extending along the y direction. The insulating sliders (19) are all embedded in the groove (18) and are slidably engaged with the groove (18). The parallel plate (6) is provided with two sliding grooves (18) extending along the y direction. The insulating slider (19) is respectively embedded in the corresponding sliding groove (18) and is slidably engaged with the sliding groove (18).

5. The voltage balancing fixture for battery cells according to claim 3, characterized in that: The positive electrode probe (7) and negative electrode probe (8) are disposed vertically on the insulating slider (19). An elastic member is sleeved between the positive electrode probe (7) and negative electrode probe (8) and the bottom of the insulating slider (19). The positive electrode probe (7) and negative electrode probe (8) are in elastic contact with the corresponding electrode post through the elastic member.

6. The voltage balancing fixture for battery cells according to claim 1, characterized in that: The bottom box (1) is provided with a first limiting component for limiting the battery cell (3) inside the bottom box (1) in the x direction and a second limiting component for limiting the battery cell (3) inside the bottom box (1) in the y direction.

7. The voltage balancing fixture for battery cells according to claim 6, characterized in that: The first limiting component includes a first sliding groove (9) and a first limiting stud (10). The first sliding groove (9) is an x-direction sliding groove symmetrically arranged on both sides of the bottom box (1) and extending along the x direction. The first limiting stud (10) penetrates the side wall of the bottom box (1) along the y direction and is slidably arranged in the x-direction sliding groove. The first limiting stud (10) is provided with hand-tightening screws (13) at both ends. The first limiting stud (10) and the battery cell (3) are limited and matched along the x direction. The second limiting component includes a second sliding groove (11) and a second limiting stud (12). The second sliding groove (11) is a y-direction sliding groove symmetrically arranged at both ends of the bottom box (1) and extending along the y direction. The second limiting stud (12) penetrates the two end walls of the bottom box (1) along the x direction and is slidably arranged in the y-direction sliding groove. The second limiting stud (12) is limited and cooperated with both sides of the battery cell (3) along the y direction.

8. The voltage balancing fixture for battery cells according to claim 1, characterized in that: The positive electrode wire (15) / negative electrode wire (16) has a female connector (25) at one end and a male connector (26) at the other end that can be plugged into the female connector (25).

9. The voltage balancing fixture for battery cells according to claim 1, characterized in that: A current-limiting resistor (17) is connected in series on each of the negative conductors (16).

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