External BMS lithium battery pack

Abstract

The utility model discloses an external BMS (Battery Management System) lithium battery pack. The external BMS lithium battery pack comprises a box body, a battery module and a BMS module, the box body is composed of a bottom shell and an upper cover, the battery module comprises a plurality of electric cores which are electrically connected, and the battery module is arranged in the box body and is fixed with the bottom shell; the BMS module comprises a cooling fin and a control panel, and the cooling fin and the control panel are connected up and down; the upper cover is provided with a mounting port, the BMS module is arranged in the mounting port, the cooling fins face the outer side, and the control panel and the battery module are electrically connected in the box body. Through the external BMS, on one hand, the cooling fins make contact with outside air, the speed of heat exchange with the outside air is increased, the working temperature of the control panel is remarkably reduced, and the heat dissipation performance is improved; and on the other hand, the BMS can be maintained or replaced outside under the condition that the battery box body is not disassembled, so that the maintenance difficulty is reduced.

Description

Technical Field

[0001] This utility model belongs to the technical field of lithium batteries, specifically relating to an external BMS lithium battery pack. Background Technology

[0002] Lithium-ion batteries are a type of battery that uses lithium metal or lithium alloy as the negative electrode material and a non-aqueous electrolyte solution. Lithium-ion batteries can be broadly classified into two categories: lithium metal batteries and lithium-ion batteries. They possess unique advantages such as low self-discharge, high voltage, light weight, and long lifespan. With the development of science and technology, lithium-ion batteries have become the mainstream.

[0003] Lithium-ion battery packs typically house modules composed of battery cells, along with a battery management system (BMS), within a casing. Because the battery BMS is mechanically fixed to the casing, this casing is usually quite sealed for safety reasons. Under high current loads, the battery itself heats up, the battery BMS heats up, and the electrical connection devices heat up. Due to the sealed casing, heat buildup leads to decreased battery performance, potentially affecting battery life or even damaging the battery. Furthermore, if the battery BMS is damaged, the sealed battery structure makes disassembly and repair of the BMS complex and difficult. Utility Model Content

[0004] To address the problems of heat accumulation, poor heat dissipation, and difficulty in disassembling and maintaining the BMS in lithium battery packs, this invention provides an external BMS lithium battery pack.

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

[0006] An external BMS lithium battery pack includes a housing, a battery module, and a BMS module. The housing consists of a bottom shell and a top cover. The battery module includes multiple electrically connected cells and is disposed within the housing and fixed to the bottom shell. The BMS module includes a heat sink and a control board, which are connected vertically. The top cover has a mounting opening, and the BMS module is installed in the mounting opening with the heat sink facing outwards. The control board is electrically connected to the battery module within the housing.

[0007] Optionally, the mounting port has a downwardly extending sidewall with an inwardly protruding periphery; the heat sink and the control board are connected vertically by a first fastener, the size of the heat sink is larger than the size of the control board, and the area where the edge extends beyond the control board overlaps with the periphery of the mounting port and is connected by a second fastener.

[0008] Optionally, the periphery is located at the bottom end of the side wall of the mounting port, and the surface of the heat sink is lower than or flush with the outer surface of the top cover.

[0009] Optionally, it also includes a sealing ring, which fits between the periphery of the mounting port and the outer edge of the heat sink and is located inside the second fastener.

[0010] Optionally, the periphery of the mounting port is provided with an annular groove that mates with the sealing ring.

[0011] Optionally, the top cover is further provided with a first external terminal and a second external terminal, and the battery module is further provided with a first lead wire and a second lead wire. The first lead wire is electrically connected to the first external terminal, and the second lead wire is electrically connected to the control board. The control board is electrically connected to the second external terminal through a connecting wire.

[0012] Optionally, the second lead and the connecting line are electrically connected to the control board via copper busbar structures.

[0013] Optionally, the battery module further includes an end plate and an insulating plate, with multiple battery cells sandwiched between two end plates, and the insulating plate disposed above the battery cells and connected and fixed to the end plates on both sides.

[0014] Optionally, the top of the side wall of the bottom shell is provided with an upwardly protruding rib, and the bottom of the side wall of the top cover is provided with a mating groove. The bottom shell and the top cover are bonded and fixed together by the rib and the mating groove to form the box body.

[0015] Optionally, the heat sink is a finned structure or a flat plate heat sink.

[0016] The beneficial effects of this utility model are as follows:

[0017] (1) The BMS module is placed on the outer surface of the battery pack, so that the heat sink can fully contact the outside air, accelerate the heat exchange with the outside air, significantly reduce the operating temperature of the control board, improve the performance of the BMS, and reduce the heat accumulation inside the battery pack.

[0018] (2) An external BMS allows the BMS to be repaired or replaced externally without disassembling the battery pack if it fails, reducing the difficulty of battery pack repair and maintenance costs.

[0019] Other features and beneficial effects of this invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing this invention. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the external BMS lithium battery pack in an embodiment.

[0021] Figure 2 This is an exploded structural diagram of the external BMS lithium battery pack in an embodiment.

[0022] Figure 3 This is a partial structural diagram of the top cover of the external BMS lithium battery pack in an embodiment.

[0023] Figure 4 This is a schematic diagram of the structure of the BMS module of the external BMS lithium battery pack in an embodiment.

[0024] Figure 5 This is a circuit connection diagram of the external BMS lithium battery pack for an embodiment.

[0025] In the diagram, 1-box body, 11-bottom shell, 111-rib, 12-top cover, 12a-mounting port, 121-side wall, 122-perimeter, 122a-mounting hole, 122b-annular groove, 123-first external terminal, 124-second external terminal, 2-battery module, 21-cell, 22-end plate, 23-insulating plate, 24-first lead wire, 25-second lead wire, 3-BMS module, 31-heat sink, 31a-connection hole, 32-control board, 321-copper busbar structure, 33-first fastener, 4-second fastener, 5-sealing ring, 6-connecting wire, 7-EVA foam adhesive. Detailed Implementation

[0026] The present invention will be further explained below with reference to the accompanying drawings and specific embodiments. The accompanying drawings are merely illustrative to facilitate understanding of the present invention, and their specific proportions can be adjusted according to design requirements. The vertical relationships of relative elements and the definitions of front / back in the graphics described herein should be understood by those skilled in the art to refer to the relative positions of the components; therefore, they can all be flipped to present the same component, and all of this should fall within the scope disclosed in this specification.

[0027] This embodiment provides an external BMS lithium battery pack, referencing... Figure 1 and Figure 2 The system includes a housing 1, a battery module 2, and a BMS module 3. The housing 1 consists of a bottom shell 11 and a top cover 12. The battery module 2 includes multiple electrically connected cells 21, and is housed within the housing 1 and fixed to the bottom shell 11. The BMS module 3 includes a heat sink 31 and a control board 32, which are connected vertically. The top cover 12 has a mounting opening 12a, in which the BMS module 3 is installed with the heat sink 31 facing outwards. The control board 32 is electrically connected to the battery module 2 within the housing 1. Mounting the BMS module 3 on the outer surface of the housing 1 and placing the heat sink 31 on the outside accelerates heat exchange with the external environment and reduces heat accumulation within the battery pack.

[0028] Specifically, in combination Figure 3and Figure 4 The mounting opening 12a of the upper cover 12 has a downwardly extending sidewall 121. The height of the sidewall 121 is set according to the thickness of the heat sink 31. The bottom end of the sidewall 121 has an inwardly protruding periphery 122. Several mounting holes 122a are distributed on the periphery 122, and an annular groove 122b is provided. The annular groove 122b is located inside the mounting holes 122a. Here, "inner" and "outer" refer to the side facing the center of the mounting opening as the inner side and the side away from the center of the mounting opening as the outer side. The heat sink 31 and the control board 32 are arranged vertically and connected by a first fastener 33. The first fastener 33 is a structure such as a bolt. It can be understood that the heat sink 31 and the control board 32 have corresponding connection holes, and are fastened together by the first fastener 33, and can be easily disassembled when needed. The size (area) of the heat sink 31 is larger than the size (area) of the control board 32. The area where the edge extends beyond the control board 32 overlaps with the periphery 122 of the mounting opening and is connected by a second fastener 4. Specifically, the edge of the heat sink 31 is provided with a connecting hole 31a. The connecting hole 31a and the mounting hole 122a correspond vertically and are fastened together by a second fastener 4, such as a screw, which can be easily disassembled when needed. Thus, the BMS module 3 closes the mounting opening 12a, forming a sealed space inside the housing 1. To further improve the sealing performance, a sealing ring 5 is provided between the periphery 122 of the mounting opening and the edge of the heat sink 31. The sealing ring 5 fits into the annular groove 122b and is located outside the control board 32, thereby placing the control board 32 and the battery module 2 in a sealed environment, preventing moisture, dust, etc., from entering the battery and avoiding short circuits and corrosion. The sealing ring 5 is, for example, a silicone waterproof gasket.

[0029] With the above configuration, the BMS module 3 is located within and closes the mounting port 12a. The surface of the heat sink 31 is lower than or flush with the outer surface of the upper cover 12, providing mechanical protection and preventing damage to the BMS module 3 from mechanical loads such as vibration, impact, and collision. The heat sink 31 is preferably a finned structure with the fins exposed to the external environment for easy heat dissipation and to reduce heat accumulation within the battery pack. Other heat sink structures, such as flat heat sinks, are also applicable and are not limited thereto.

[0030] Combination Figure 5The battery module 2 also includes end plates 22 and insulating plates 23. Multiple battery cells 21 are arranged in sequence and connected in series or parallel, sandwiched between two end plates 22. After the end plates 22 clamp the battery cells 21, they fix the two end plates 22 to each other. The end plates 22 are used to compress the battery cells 21 to prevent battery expansion and improve battery cycle life. The insulating plate 23 is located above the battery cells 21 and is connected and fixed to the two end plates 22. The insulating plate 23 is located between the battery cells 21 and the control board 32 for electrical isolation, improving electrical safety and reliability. The battery module 2 also has a first lead 24 and a second lead 25 as positive and negative leads. The top cover 12 is provided with a first external terminal 123 and a second external terminal 124. The first lead 24 is electrically connected to the first external terminal 123, and the second lead 25 is electrically connected to the control board 32. The control board 32 and the second external terminal 124 are electrically connected through a connecting wire 6. The second lead-out line 25 and the connecting line 6 are electrically connected to the control board 32 via a copper busbar structure 321, which facilitates connection and disassembly.

[0031] The Battery Management System (BMS) is used to monitor and manage the battery status. The control board 32 of the BMS module is connected in series with the external circuit of the battery to provide status monitoring, charge and discharge management, battery balancing, safety balancing and other management and control. Specifically, it includes but is not limited to real-time monitoring of battery parameters such as voltage, current and temperature, optimizing the battery charge and discharge curve, preventing overcharging and over-discharging, and providing overvoltage, overcurrent and overtemperature protection mechanisms to ensure the battery's safety, efficient operation and long life.

[0032] In the assembly of housing 1, refer to Figure 2 The bottom shell 11 has upward-protruding ribs 111 at the top of its side wall, and the top cover 12 has a mating groove (not shown in the figure) at the bottom of its side wall. Adhesive is filled into the mating groove of the top cover 12, and it is assembled with the ribs 111 of the bottom shell 11 to complete the bonding and fixing of the housing 1, providing mechanical support and protection for the internal battery structure. The battery module 2 can be fixed to the bottom shell 11 by means of bonding with EVA foam adhesive 7 or fasteners to prevent displacement during transportation or operation. After the housing 1 is assembled, the BMS module 3 is installed and the wiring is connected. When the BMS is damaged, it can be repaired or replaced externally without disassembling the battery housing 1. Furthermore, the control board 32 can be processed separately by disassembling and disassembling the BMS module 3 without affecting the housing 1 and the battery module 2, reducing the repair difficulty and maintenance cost of the BMS.

[0033] The above embodiments are only used to further illustrate an external BMS lithium battery pack of the present invention. However, the present invention is not limited to the embodiments. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. An external BMS lithium battery pack, characterized in that: The application relates to a battery module, which comprises a box, a battery module and a BMS module; the box is composed of a bottom shell and an upper cover; the battery module comprises a plurality of electric cores connected by electricity; the battery module is arranged in the box and fixed to the bottom shell; the BMS module comprises a heat dissipation fin and a control board; the heat dissipation fin and the control board are connected in an up-down mode; the upper cover is provided with a mounting port; the BMS module is arranged in the mounting port and the heat dissipation fin faces the outside; the control board is electrically connected with the battery module in the box.

2. The external BMS lithium battery pack according to claim 1, wherein: The mounting port has a side wall extending downward, and the side wall has a periphery protruding inward; the heat dissipation fin and the control board are connected in an up-down mode through a first fastener; the size of the heat dissipation fin is larger than that of the control board; the area of the edge exceeding the control board is overlapped with the periphery of the mounting port and connected through a second fastener.

3. The external BMS lithium battery pack of claim 2, wherein: The periphery is located at the bottom end of the side wall of the mounting port; the surface of the heat dissipation fin is lower than or flush with the outer surface of the upper cover.

4. The external BMS lithium battery pack of claim 2, wherein: A sealing ring is further arranged between the periphery of the mounting port and the outer edge of the heat dissipation fin and located at the inner side of the second fastener.

5. The external BMS lithium battery pack according to claim 4, wherein: The periphery of the mounting port is provided with an annular groove matched with the sealing ring.

6. The external BMS lithium battery pack of claim 1, wherein: The upper cover is further provided with a first external terminal and a second external terminal; the battery module is further provided with a first lead-out wire and a second lead-out wire; the first lead-out wire is electrically connected with the first external terminal; the second lead-out wire is electrically connected with the control board; the control board is electrically connected with the second external terminal through a connecting wire.

7. The external BMS lithium battery pack of claim 6, wherein: The second lead-out wire and the connecting wire are respectively electrically connected with the control board through a copper bar structure.

8. The external BMS lithium battery pack of claim 1, wherein: The battery module further comprises end plates and an insulating plate; a plurality of electric cores are clamped between two end plates; the insulating plate is arranged above the electric cores and fixedly connected with the end plates on both sides.

9. The external BMS lithium battery pack of claim 1, wherein: The top end of the side wall of the bottom shell is provided with a rib protruding upward; the bottom end of the side wall of the upper cover is provided with a matching groove; the bottom shell and the upper cover are adhesively fixed to form the box through the rib and the matching groove.

10. The external BMS lithium battery pack of claim 1, wherein: The heat dissipation fin is in a fin type structure or a flat plate heat dissipation fin.

Images