Lithium battery pack

Abstract

The utility model relates to a lithium battery pack which comprises a battery cell support, a battery cell assembly arranged on the battery cell support and a protection circuit board arranged on the side face of the battery cell support and used for managing charging and discharging of the battery cell assembly, and the battery cell assembly comprises a plurality of battery cells and a plurality of first connecting pieces connected to the positive electrodes and the negative electrodes of the battery cells. The first connecting piece comprises a first connecting end, the protective circuit board comprises a connecting point corresponding to the first connecting end and a fastener, and the first connecting end is locked at the connecting point through the fastener, so that the first connecting piece is conducted with the protective circuit board. According to the lithium battery pack designed by the utility model, potential adverse effects caused by tin soldering are avoided, and meanwhile, the production efficiency of the battery pack is improved.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a lithium battery pack. Background Technology

[0002] A lithium battery pack is a power supply device composed of one or more battery cells. A protection circuit board protects and controls the cells. By assembling the battery pack with the main unit, the lithium battery can safely supply power to the device. In existing lithium battery packs, the cells and the protection circuit board are electrically connected via connectors. These connections are soldered using a soldering iron, typically at around 350℃. This high-temperature soldering process can potentially adversely affect the electronic components and cells surrounding the solder pads. The soldering process also easily produces solder dross and solder balls, which, if splashed into the battery pack, may pose a safety hazard. Furthermore, the soldering process has low production efficiency and is difficult to automate. Utility Model Content

[0003] To address the aforementioned problems, the purpose of this utility model is to design a lithium battery pack that solves the potential adverse effects of soldering while improving battery pack production efficiency.

[0004] The objective of this utility model is achieved through the following technical solution:

[0005] A lithium battery pack includes a cell support, a cell assembly disposed on the cell support, and a protection circuit board disposed on the side of the cell support for managing the charging and discharging of the cell assembly. The cell assembly includes a plurality of cells and a plurality of first connecting pieces connected to the positive and negative terminals of the cells. Each first connecting piece includes a first connecting end. The protection circuit board includes a connection point corresponding to the first connecting end and a fastener. The first connecting end is locked to the connection point by the fastener so that the first connecting piece is connected to the protection circuit board.

[0006] This lithium battery pack design uses a cell support frame to support the cell components and insulate them from the protection circuit board. The protection circuit board is located on the side of the cell support frame. The cells are connected in series or parallel via a first connecting piece. The first connecting end of the first connecting piece extends to the connection point on the protection circuit board. Fasteners are used to lock the first connecting end onto the connection point on the protection circuit board, achieving electrical connection between the two. By using a fastener locking connection method instead of the traditional soldering connection method, the risks of high temperatures affecting electronic components and cells during soldering, as well as solder dross or solder balls splashing into the battery pack, are solved. Furthermore, the fastener locking connection method can be implemented in automated equipment to automatically attach the fasteners, thereby improving production efficiency.

[0007] Furthermore, the first connecting end is provided with a first connecting hole, and the connecting point includes a second connecting hole corresponding to the first connecting hole. The inner wall of the second connecting hole is covered with a conductive layer, which is connected to the circuit of the protection circuit board. The fastener passes through the first connecting hole and the second connecting hole so that the first connecting end is in close contact with the connecting point.

[0008] The first connecting end is provided with a first connecting hole, and the connecting point is provided with a second connecting hole corresponding to the first connecting hole. The fastener passes through the first connecting hole and the second connecting hole and applies pressure to make the connecting end faces fit tightly, forming a physical lock. The inner wall of the second connecting hole is covered with a conductive layer, which is a copper-plated layer. The structure of the conductive layer is not affected after the fastener is removed, thus facilitating equipment maintenance or component replacement and reducing maintenance costs.

[0009] Furthermore, the connection point also includes a conductive disk, which is located on two surfaces in the height direction of the protective circuit board and laid around the second connection hole. The conductive disk is conductively connected to the conductive layer.

[0010] The first connecting end of the first connecting piece contacts the conductive disk. By setting the conductive disk, a larger contact area is provided, the contact resistance is reduced, the current carrying capacity is improved, and the heat generation and power loss are reduced.

[0011] Furthermore, the first connection hole is provided with a protruding structure, which abuts against the conductive disc on the surface of the protection circuit board near the cell support.

[0012] The first connection hole is a stamped cross-shaped or tapered hole, with a raised structure near the protective circuit board. The raised structure is designed to abut against the conductive pad, increasing the contact area through physical pressure and significantly reducing contact resistance. After the fasteners are tightened, the raised structure creates localized stress concentration, which can effectively suppress minor displacements caused by vibration.

[0013] Furthermore, the fastener is a metal screw.

[0014] The fasteners are metal screws, preferably copper screws, which have good electrical conductivity. By contacting the first and second connecting holes with the copper screws, the contact resistance can be reduced and the current transmission efficiency can be improved. The nut of the copper screw contacts the conductive disk away from the first connecting piece, which further increases the contact area and reduces the contact resistance.

[0015] Furthermore, the battery cell bracket is provided with locking holes that correspond one-to-one with the second connection hole, and the fastener passes through the first connection hole and the second connection hole to lock and connect with the locking hole.

[0016] The fastener passes through the first and second connecting holes and locks into the locking hole, thus achieving a pressurized connection between the first connecting piece and the connecting point. It also secures the circuit board, eliminating the need for additional fasteners to lock and protect the circuit board. This improves assembly efficiency and reduces material costs.

[0017] Furthermore, the battery cell bracket is provided with limiting steps that correspond one-to-one with the first connecting end, the first connecting end is attached to the limiting step, and the locking hole is located on the limiting step.

[0018] The limiting step is used to restrict the position of the first connecting end of the first connecting piece, and also to support the first connecting end. When the first connecting end is attached to the limiting step, the first connecting hole is opposite to the locking hole, which makes it easy for the fastener to pass through.

[0019] Furthermore, the battery cell support is provided with a plurality of first positioning posts, and the protection circuit board is provided with first positioning holes corresponding one-to-one with the first positioning posts.

[0020] The protection circuit board is locked onto the cell bracket by fasteners. Specifically, the protection circuit board and the cell bracket are precisely positioned by a positioning structure consisting of a first positioning hole and a first positioning post, so that the second connecting hole of the protection circuit board is connected to the first connecting hole of the first connecting piece and the locking hole of the cell bracket. Then, the protection circuit board is locked onto the cell bracket by fasteners.

[0021] Furthermore, the first connecting piece is provided with a second positioning hole, and the battery cell bracket is provided with a second positioning post corresponding to the second positioning hole.

[0022] To further ensure the accuracy of the first connecting piece's position on the cell bracket, a positioning structure consisting of a second positioning hole and a second positioning post is provided between the first connecting piece and the cell bracket. The positioning structure ensures that the first connecting end of the first connecting piece can be attached to the limiting step, and the end of the first connecting piece away from the first connecting end corresponds to the positive and negative terminals of the cell.

[0023] Compared with the prior art, the beneficial effects of this utility model are:

[0024] This lithium battery pack design uses a cell support frame to support the cell components and insulate them from the protection circuit board. The protection circuit board is located on the side of the cell support frame. The cells are connected in series or parallel via a first connecting piece. The first connecting end of the first connecting piece extends to the connection point on the protection circuit board. Fasteners are used to lock the first connecting end onto the connection point on the protection circuit board, achieving electrical connection between the two. By using a fastener locking connection method instead of the traditional soldering connection method, the risks of high temperatures affecting electronic components and cells during soldering, as well as solder dross or solder balls splashing into the battery pack, are solved. Furthermore, the fastener locking connection method can be implemented in automated equipment to automatically attach the fasteners, thereby improving production efficiency. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the structure of a lithium battery pack according to an embodiment of the present invention.

[0026] Figure 2 for Figure 1 A magnified view of part A in the image.

[0027] Figure 3 This is an exploded view of a lithium battery pack according to an embodiment of the present invention.

[0028] Figure 4 for Figure 3 A magnified view of part B in the image.

[0029] Figure 5 for Figure 3 A magnified view of part C.

[0030] Figure 6 This is an example diagram of a first connecting piece according to an embodiment of the present invention.

[0031] Figure 7 for Figure 6 A magnified view of part of D.

[0032] Illustrations: 1. Cell support; 11. Limiting step; 12. First support; 13. Second support; 14. Locking hole; 15. First positioning post; 16. Second positioning post; 2. Cell assembly; 21. Cell; 22. First connecting piece; 221. First connecting end; 222. First connecting hole; 223. Protruding structure; 224. Second positioning hole; 3. Protective circuit board; 31. Connection point; 32. Fastener; 33. First positioning hole; 311. Second connecting hole; 312. Conductive layer; 313. Conductive disc. Detailed Implementation

[0033] To facilitate understanding of this invention, a more comprehensive description will be provided below with reference to the accompanying drawings. The drawings illustrate preferred embodiments of the invention. However, this invention can be implemented in many different forms and is not limited to the embodiments described herein.

[0034] like Figures 1 to 7 As shown, this embodiment provides a lithium battery pack, including a cell support 1, a cell assembly 2 disposed on the cell support 1, and a protection circuit board 3 disposed on the side of the cell support 1 for managing the charging and discharging of the cell assembly 2. The cell assembly 2 includes multiple cells. The cell support 1 includes a first support 12 and a second support 13, which together form a cavity for accommodating the cells 21. Cell slots corresponding to the cells 21 are provided within the cavity. In this embodiment, the cell assembly 2 includes five cells 21, and five cell slots are correspondingly provided. By designing cell slots that correspond one-to-one with the cells 21, stable support is provided for the cells 21. Corresponding first locking holes and second locking holes are provided between the first support 12 and the second support 13. After the first support 12 and the second support 13 are closed, the first locking holes and the second locking holes are connected and screwed together by threaded fasteners. The battery cell assembly 2 also includes a first connecting piece 22, which is made of molded nickel sheet. In other embodiments, the first connecting piece 22 may also be made of conductive metal such as copper sheet. The specific material of the first connecting piece 22 is not specifically limited here. The five battery cells 21 are connected in series through six first connecting pieces 22. The first connecting piece 22 includes a first connecting end 221. The protection circuit board 3 includes a connection point 31 corresponding to the first connecting end 221 and a fastener 32. The first connecting end 221 is locked to the connection point 31 by the fastener 32 so that the first connecting piece 22 is connected to the protection circuit board 3. The shape of the first connecting piece 22 is not specifically limited, as long as it realizes its electrical connection function.

[0035] like Figures 1 to 4 As shown, the first connecting piece 22 is disposed at both ends of the cell support 1. The cell support 1 has a limiting step 11 corresponding to the first connecting end 221. The first connecting end 221 is attached to the limiting step 11. To ensure the accuracy of the position of the first connecting piece 22 on the cell support 1, the first connecting piece 22 is provided with a second positioning hole 224. The cell support 1 is provided with a second positioning post 16 corresponding to the second positioning hole 224. The positioning structure composed of the second positioning hole 224 and the second positioning post 16 ensures that the first connecting end 221 of the first connecting piece 22 can be attached to the limiting step 11. The end of the first connecting piece 22 away from the first connecting end 221 corresponds to the positive and negative terminals of the cell 21. The limiting step 11 is used to restrict the position of the first connecting end 221 of the first connecting piece 22 and also provides support for the first connecting end 221.

[0036] like Figures 3 to 7 As shown, the first connecting end 221 is provided with a first connecting hole 222, and the connecting point 31 includes a second connecting hole 311 corresponding to the first connecting hole 222. The limiting step 11 is provided with locking holes 14 corresponding to the second connecting holes 311. When the protection circuit board 3 is installed on the cell bracket 1, the first connecting hole 222, the second connecting hole 311 and the locking hole 14 are connected. The fastener 32 passes through the first connecting hole 222 and the second connecting hole 311 to lock and connect with the locking hole 14, so that the first connecting end 221 and the connecting point 31 are tightly attached to form a physical lock. This realizes the pressing connection between the first connecting piece 22 and the connecting point 31, and also realizes the fixation of the protection circuit board 3. There is no need to set additional fasteners 32 to lock the protection circuit board 3, which improves the assembly efficiency and reduces the material cost. The cell bracket 1 is provided with a plurality of first positioning posts 15, and the protection circuit board 3 is provided with first positioning holes 33 corresponding to the first positioning posts 15. Precise positioning is achieved through the positioning structure composed of the first positioning hole 33 and the first positioning post 15, so that the second connection hole 311 of the protection circuit board 3 is connected to the first connection hole 222 of the first connecting piece 22 and the locking hole 14 of the cell bracket 1, and then the protection circuit board 3 is locked onto the cell bracket 1 by the fastener 32.

[0037] like Figure 6 and Figure 7As shown, the inner wall of the second connection hole 311 is covered with a conductive layer 312, which is a copper-plated layer. The conductive layer 312 is conductive to the circuit of the protection circuit board 3. The connection point 31 also includes a conductive disk 313, which is located on two surfaces in the height direction of the protection circuit board 3 and is laid around the second connection hole 311. The conductive disk 313 is conductively connected to the conductive layer 312. The first connection hole 222 is provided with a protruding structure 223, which abuts against the conductive disk 313 on the surface of the protection circuit board 3 near the cell support 1. The fastener 32 passes through the first connection hole 222 and the second connection hole 311 and applies pressure to make the first connection end 221 of the first connection piece 22 contact the conductive disk 313. By setting the conductive disk 313, a larger contact area is provided, the contact resistance is reduced, the current carrying capacity is improved, and heat generation and power loss are reduced. The first connecting hole 222 is a stamped cross-shaped or tapered hole, with a raised structure 223 formed on the side near the protective circuit board 3. The raised structure 223 is designed to abut against the conductive disk 313, increasing the contact area through physical pressure and significantly reducing contact resistance. After the fastener 32 is tightened, the raised structure 223 forms a local stress concentration, which can effectively suppress minor displacement caused by vibration. The fastener 32 is a metal screw, preferably a copper screw. Copper screws have good electrical conductivity. By contacting the first connecting hole 222 and the second connecting hole 311 with the copper screw, the contact resistance can be reduced and the current transmission efficiency can be improved. The nut of the copper screw contacts the conductive disk 313 away from the first connecting piece 22, further increasing the contact area and reducing the contact resistance. In other possible embodiments, the fastener 32 may also use screws made of other metal materials, which are not specifically limited here.

[0038] In addition, to further reduce the contact resistance between the first connecting piece 22 and the connection point 31, multiple second connecting holes 311 can be provided at one connection point 31. The first connecting piece 22 and the cell bracket 1 are respectively provided with a corresponding number of first connecting holes 222 and locking holes 14. In this embodiment, the cell assembly 2 includes five cells 21. In other possible embodiments, the number of cells 21 can be adapted and is not specifically limited here.

[0039] In this embodiment, the lithium battery pack supports the cell assembly 2 via a cell bracket 1, which insulates and isolates the cell assembly 2 from the protection circuit board 3. The protection circuit board 3 is located on the side of the cell bracket 1. The cells 21 are connected in series or in parallel via a first connecting piece. The first connecting end 221 of the first connecting piece 22 extends to the connection point 31 of the protection circuit board 3. The first connecting end 221 is locked onto the connection point 31 of the protection circuit board 3 by a fastener 32, thus achieving electrical connection between the two. By using a fastener 32 locking connection method instead of the traditional soldering connection method, the risks of high temperature affecting electronic components and cells during soldering, as well as solder dross or solder balls splashing into the battery pack, are solved. At the same time, the fastener 32 locking connection method can be introduced into automated equipment to achieve automatic fastening of the fastener 32, thereby improving production efficiency.

[0040] In the description of this utility model, it should be understood that terms such as "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" 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 utility model 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 utility model.

[0041] Furthermore, the terms "first," "second," etc., 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. Therefore, the inclusion of "first," "second," etc., in a feature may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0042] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A lithium battery pack, characterized in that, The device includes a cell support, a cell assembly mounted on the cell support, and a protection circuit board mounted on the side of the cell support for managing the charging and discharging of the cell assembly. The cell assembly includes a plurality of cells and a plurality of first connecting pieces connected to the positive and negative terminals of the cells. Each first connecting piece includes a first connecting end. The protection circuit board includes a connection point corresponding to the first connecting end and a fastener. The first connecting end is locked to the connection point by the fastener so that the first connecting piece is connected to the protection circuit board.

2. The lithium battery pack according to claim 1, characterized in that, The first connecting end is provided with a first connecting hole, and the connecting point includes a second connecting hole corresponding to the first connecting hole. The inner wall of the second connecting hole is covered with a conductive layer, which is connected to the circuit of the protection circuit board. The fastener passes through the first connecting hole and the second connecting hole so that the first connecting end is in close contact with the connecting point.

3. The lithium battery pack according to claim 2, characterized in that, The connection point also includes a conductive disk, which is located on two surfaces in the height direction of the protective circuit board and laid around the second connection hole. The conductive disk is conductively connected to the conductive layer.

4. The lithium battery pack according to claim 3, characterized in that, The first connection hole has a raised structure, which abuts against the conductive disc on the surface of the protection circuit board near the cell support.

5. The lithium battery pack according to claim 2, characterized in that, The fastener is a metal screw.

6. The lithium battery pack according to claim 2, characterized in that, The cell support is provided with locking holes that correspond one-to-one with the second connection hole, and the fastener passes through the first connection hole and the second connection hole to lock and connect with the locking hole.

7. The lithium battery pack according to claim 6, characterized in that, The cell support is provided with a limiting step that corresponds to the first connecting end. The first connecting end is attached to the limiting step, and the locking hole is located on the limiting step.

8. The lithium battery pack according to claim 1, characterized in that, The battery cell support is provided with a plurality of first positioning posts, and the protection circuit board is provided with first positioning holes corresponding one to one of the first positioning posts.

9. The lithium battery pack according to claim 1, characterized in that, The first connecting piece is provided with a second positioning hole, and the battery cell bracket is provided with a second positioning post corresponding to the second positioning hole.

Images