Power supply device of low-speed electric vehicle

Abstract

The utility model relates to a low-speed electric vehicle power supply device which comprises a box body, battery cells and a DCDC power supply module, at least one battery cell is arranged in the battery box body, when the number of the battery cells is larger than one, a plurality of partition plates which are evenly distributed in parallel are arranged in the box body, the box body is divided into a plurality of partition bins through the partition plates, and one battery cell is arranged in each partition bin; the top surfaces of the battery cells are welded and connected in series through connecting sheets to form a battery module; a box cover of the box body adopts a supporting cover plate, the supporting cover plate is connected with the box body in a nested manner, and a DCDC power supply module is arranged above the supporting cover plate; a battery terminal outgoing line of the battery cell penetrates through the supporting cover plate and then is inserted into the low-voltage input end of the DCDC power module, and the high-voltage output end of the DCDC power module is connected with an external plug through a power line. The utility model has the advantages of simple structure, low cost, high assembly efficiency, good safety, good system heat dissipation, long cycle life and the like.

Description

Technical Field

[0001] The utility model relates to the technical field of power supply, in particular to a power supply device for a low-speed electric vehicle. Background Art

[0002] Low-speed electric vehicles are broadly defined to include electric bicycles, electric motorcycles, electric tricycles and low-speed electric vehicles, etc. They are lightweight, flexible and convenient. Under the environmentally friendly trend of developing new energy, low-speed electric vehicles have a large market size.

[0003] The power supply voltage level of low-speed electric vehicles is generally 24-72V, and the system capacity is generally 10-40Ah. The overall characteristics are small kilowatt-hours and relatively low power. On the other hand, low-speed electric vehicles are mainly aimed at the convenient consumer market, which requires its power supply to have low cost, high safety, and durability. The traditional low-speed power supply usually uses dozens of small-capacity single batteries in series and parallel to form the target voltage level and capacity, and welds the protection board into the box to form a system. See Figure 1 , Figure 1 This is a diagram of the components of a traditional low-speed electric vehicle power supply. The existing power supply system is complex to assemble, and the consistency of dozens of small-capacity batteries is difficult to screen, control and ensure at the source. In addition, this simple protection board mechanism causes problems such as low control accuracy, small protection range, and slow response speed. The single battery in the power supply system will inevitably have large pressure difference, overcharge and over discharge during operation, which will lead to low system cycle life, fire and explosion and other incidents.

[0004] Therefore, based on the above-mentioned defects in the prior art, there is an urgent need in the art to develop a simple, efficient, low-cost, and highly safe low-speed power dedicated power supply. Summary of the invention

[0005] The purpose of the utility model is to overcome the above-mentioned shortcomings and provide a low-speed electric vehicle power supply device, which has the advantages of simple structure, low cost, high assembly efficiency, good safety, good system heat dissipation, and long cycle life.

[0006] The purpose of the utility model is achieved in this way:

[0007] A power supply device for a low-speed electric vehicle comprises a box, a battery cell and a DCDC power supply module. The battery box is provided with at least one battery cell. When the number of battery cells is greater than one, a plurality of evenly distributed parallel partitions are provided in the box, and the box is divided into a plurality of compartments by the partitions, and a battery cell is provided in each compartment. The top surfaces of the battery cells are welded in series through connecting sheets to form a battery module. When only one battery cell is provided, the battery cell is directly provided in the box.

[0008] The box cover of the box body adopts a supporting cover plate, which is nested with the box body, and a DCDC power module is arranged above the supporting cover plate; the battery terminal lead wires of the battery cell pass through the supporting cover plate and are inserted into the low-voltage input end of the DCDC power module, and the high-voltage output end of the DCDC power module is connected to an external plug through a power cord.

[0009] Furthermore, upper bolt conducting columns are respectively provided at the four outer corners of the support cover plate, and lower bolt conducting columns are respectively provided at the four outer corners of the box body. The upper bolt conducting columns correspond to the lower bolt conducting columns, and the locking of the support cover plate and the box body is achieved by inserting bolts and nuts.

[0010] Furthermore, a side surface of the support cover plate is provided with a lead-out port, and the lead-out port is arranged on the same side as the battery terminal lead-out wires of the battery cell, so as to facilitate leading out the battery terminal lead-out wires of the battery cell.

[0011] Furthermore, the heat dissipation back plate of the DCDC power module is arranged in a direction away from the box body, and the thermal conductive silicone encapsulation surface of the electronic components of the DCDC power module is arranged in a direction close to the box body.

[0012] Furthermore, a slot is provided on the top surface of the support cover, and the DCDC power module 5 is inserted into the slot on the top surface of the support cover.

[0013] Furthermore, the battery cells are connected by a soft connection method using a connecting piece, an arched buffer belt is provided in the middle of the connecting piece, and the connecting piece can be made of an aluminum bar.

[0014] Compared with the prior art, the beneficial effects of the utility model are:

[0015] The utility model provides a low-speed electric vehicle power supply device, which avoids the series-parallel structure of a large number of small-capacity battery cells and adopts a simple large-cell series structure. The unit wh cost of the large battery cell is lower, and the system assembly eliminates the need for additional insulation and pack accessories, further reducing costs; the utility model adopts 1-3 large battery cells to form a battery module with soft connection, and the screening of battery consistency is simpler and more reliable. The system will not have overcharge or over-discharge when working, which greatly improves the cycle life and safety of the power supply system; the number of assembled parts is reduced, the efficiency is higher, the reliability of the system is greatly improved, and its maintenance and repair are more convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a diagram showing the components of a traditional low-speed electric vehicle power supply.

[0017] Figure 2 It is a structural schematic diagram of the utility model.

[0018] Figure 3 It is an exploded view of the utility model.

[0019] Figure 4 It is a component composition diagram of the utility model.

[0020] in:

[0021] Box body 1, partition 11, partition compartment 12, lower bolt conduction column 13, battery cell 2, connecting piece 3, support cover plate 4, upper bolt conduction column 41, DCDC power module 5, power cord 6, plug 7. DETAILED DESCRIPTION

[0022] In order to better understand the technical solution of the present invention, the following will be described in detail in conjunction with the relevant illustrations. It should be understood that the following specific embodiments are not intended to limit the specific implementation of the technical solution of the present invention, and are only implementations that can be adopted by the technical solution of the present invention. It should be noted that the description of the positional relationship of each component in this article, such as component A being located above component B, is based on the description of the relative positions of the components in the illustration, and is not intended to limit the actual positional relationship of the components. Example 1

[0023] See also Figure 2-Figure 4 , Figure 2 The structural schematic diagram of the utility model is drawn. As shown in the figure, the utility model relates to a low-speed electric vehicle power supply device, which includes a battery box 1, a battery cell 2 and a DCDC power module 5. The battery box 1 is provided with 1 to 3 battery cells 2. When the number of battery cells 2 is greater than 1, a plurality of parallel and evenly distributed partitions 11 are provided in the box 1, and the box 1 is divided into a plurality of compartments 12 by the partitions 11, and a battery cell 2 is provided in each compartment 12; the top surface of the battery cell 2 is welded in series through a connecting piece 3 to form a battery module.

[0024] The box cover of the box body 1 adopts a support cover plate 4, and the support cover plate 4 is connected to the box body 1 in a male-female manner. The four outer corners of the support cover plate 4 are respectively provided with upper bolt conduction columns 41, and the four outer corners of the box body 1 are respectively provided with lower bolt conduction columns 13. The upper bolt conduction columns 41 are matched with the lower bolt conduction columns 13 in a one-to-one manner, and the locking of the support cover plate 4 and the box body 1 is achieved by inserting bolts and nuts.

[0025] A lead-out port is provided on one side of the support cover plate 4 , and the lead-out port is arranged on the same side as the battery terminal lead-out wires of the battery cell 2 , so as to facilitate leading out the battery terminal lead-out wires of the battery cell 2 .

[0026] A card slot is provided on the top surface of the support cover plate 4, and a DCDC power module 5 is arranged above the support cover plate 4. The heat dissipation backplane of the DCDC power module 5 is arranged upward, and the electronic components are packaged with thermal conductive silicone downward; the DCDC power module 5 is inserted into the card slot on the top surface of the support cover plate 4, and the battery terminal lead wire of the battery cell 2 is inserted into the low-voltage input end of the DCDC power module 5.

[0027] The high voltage output end of the DCDC power module 5 is connected to an external plug 7 via a power line 6 .

[0028] In this embodiment, two battery cells 2 are arranged in the box body 1, the single cell capacity of the battery cell 2 is 314Ah, and the two large-capacity single cells are directly placed in the compartment; no additional packing materials are required, and the total power is 2kwh.

[0029] In this embodiment, the voltage range of the DCDC power module 5 is 4-7.2V, the high voltage end is 30-54V; the maximum power is 800W; and it has functions such as automatic sleep and voltage protection.

[0030] In this embodiment, the battery cells 2 are connected by a soft connection method using a connecting piece 3. The connecting piece 3 can be made of an aluminum bar. An arched buffer zone is provided in the middle of the connecting piece 3. The connecting piece 3 is formed by hot pressing and welding 12-15 layers of 0.1 mm aluminum foil. The aluminum bar is connected to the battery cell pole by laser welding.

[0031] In this embodiment, the lead-out terminals of the battery cell 2 are connected by flexible wires.

[0032] In this embodiment, the box body 1 can be made of ABS+glass fiber material. ABS engineering plastic has the advantages of high strength, easy injection molding, and light weight. The support cover plate 4 is made of the same material as the box body 1: ABS+glass fiber material.

[0033] Working principle:

[0034] A low-speed electric vehicle power supply device of the present embodiment is a module-free structure, including three major parts: a large-capacity battery cell, a box body, and a DCDC bidirectional power conversion module. The base of the battery box body is made of a corresponding number of partition units according to the number of batteries, and the batteries are placed in the partition units. The top is welded in series with aluminum bars to form a battery module, and the power wiring terminals are welded with soft wires at the same time. A cover plate is provided on the top of the battery module, and the cover plate is nested with the base and locked by bolts around to form a simple power source. A card slot is provided on the top of the cover plate, and the packaged DCDC integrated power module is fixed in the card slot. The power supply wiring terminal is inserted into the low-voltage port of the DCDC module, and the DCDC high-voltage port leads to a socket for the electric vehicle motor to access.

[0035] The base of the box is made of engineering plastic or stainless steel, with a partition in the middle, which is divided into several compartments according to the number of batteries; there are bolt-through columns at the four outer corners of the top of the base of the box.

[0036] The large-capacity battery cell is a square aluminum shell battery. The positive electrode material system is one or more of lithium iron phosphate, ternary, lithium manganese oxide, and lithium manganese iron phosphate. The single cell capacity is greater than or equal to 200Ah, and the quantity is 1-3. The large-capacity battery cell is placed in the compartment.

[0037] The aluminum busbar for welding adopts a soft connection structure.

[0038] The material of the support cover is engineering plastic or stainless steel, which is consistent with the base of the box. A groove is set at the bottom to form a male-female match with the base of the box. Bolt-through columns are set at the outer edges of the four corners to match the base of the box. There is a concave notch on one side of the partition for the battery line speed to be exported. A slot position is set on the top of the partition for the installation of the DCDC power supply.

[0039] The DCDC power module is a bidirectional power module. The electronic components are encapsulated with silicone and the backplane is a pure metal surface for DCDC heat dissipation. The DCDC power module has the following functions: 1) Low voltage input voltage range 2-12.6V, high voltage output voltage range 24-96V; 2) Energy conversion efficiency ≥ 90%; 3) Power ≤ 1000w; 4) With automatic sleep and wake-up functions; 5) Voltage protection function.

[0040] The assembly process of a power source for a low-speed electric vehicle in this embodiment is as follows:

[0041] Place two 314Ah large-capacity battery cells in the compartment at the base of the battery box, fix the soft-connect aluminum bar so that the circular hole on the welding surface of the aluminum bar is concentric with the central circular hole of the battery pole; weld the aluminum bar to the pole by laser penetration welding.

[0042] The supporting partition is embedded in the base of the battery box; the groove surface on the side of the partition is located on the same side as the battery terminal lead-out wire, and the battery terminal lead-out soft wire is led out through the partition groove; the supporting partition and the bottom of the box are locked by bolts and nuts at the four corners of the outer edge;

[0043] The DCDC power module is directly inserted into the slot on the top of the supporting partition, and the soft wire led out of the battery terminal is directly inserted into the low-voltage input end of the DCDC power module; the high-voltage output end is led out of the socket and the assembly is completed.

[0044] The above are only specific application examples of the utility model, and do not constitute any limitation on the protection scope of the utility model. Any technical solution formed by equivalent transformation or equivalent replacement falls within the protection scope of the utility model.

Claims

1. A power supply device for a low-speed electric vehicle, characterized in that: It comprises a battery box (1), a battery cell (2) and a DCDC power module (5); the box (1) is provided with at least one battery cell (2); when the number of the battery cells (2) is greater than one, a plurality of evenly distributed parallel partitions (11) are provided in the box (1); the box (1) is divided into a plurality of compartments (12) by the partitions (11); a battery cell (2) is provided in each compartment (12); the top surfaces of the battery cells (2) are welded in series via connecting sheets (3) to form a battery module; when only one battery cell (2) is provided, the battery cell (2) is directly provided in the box (1); The box cover of the box body (1) adopts a supporting cover plate (4), the supporting cover plate (4) and the box body (1) are connected in a nested manner, and a DCDC power module (5) is arranged above the supporting cover plate (4); the battery terminal lead wires of the battery cell (2) pass through the supporting cover plate (4) and are inserted into the low-voltage input end of the DCDC power module (5), and the high-voltage output end of the DCDC power module (5) is connected to an external plug (7) through a power line (6).

2. A low-speed electric vehicle power supply device according to claim 1, characterized in that: The four outer corners of the support cover plate (4) are respectively provided with upper bolt guide columns (41), and the four outer corners of the box body (1) are respectively provided with lower bolt guide columns (13). The upper bolt guide columns (41) correspond to and match the lower bolt guide columns (13), and the support cover plate (4) and the box body (1) are locked by inserting bolts and nuts.

3. A low-speed electric vehicle power supply device according to claim 1, characterized in that: A lead-out port is provided on one side of the support cover plate (4), and the lead-out port is arranged on the same side as the battery terminal lead-out wire of the battery cell (2), so as to facilitate leading out the battery terminal lead-out wire of the battery cell (2).

4. A low-speed electric vehicle power supply device according to claim 1, characterized in that: The heat dissipation back plate of the DCDC power module (5) is arranged in a direction away from the box (1), and the heat conductive silica gel encapsulation surface of the electronic components of the DCDC power module (5) is arranged in a direction close to the box (1).

5. A low-speed electric vehicle power supply device according to claim 1, characterized in that: The top surface of the support cover plate (4) is provided with a slot, and the DCDC power supply module (5) is inserted into the slot on the top surface of the support cover plate (4).

6. A low-speed electric vehicle power supply device according to claim 1, characterized in that: The battery cells (2) are connected in a soft connection manner using a connecting piece (3); an arched buffer belt is provided in the middle of the connecting piece (3); and the connecting piece (3) can be made of an aluminum bar.

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