Low-cost power battery pack structure

Abstract

The utility model relates to a low-cost power battery pack structure which comprises a box body, the box body comprises a frame and a bottom plate connected with the bottom of the frame, and both the frame and the bottom plate are formed by rolling high-strength cold-rolled steel. The frame and the bottom plate of the box body are manufactured by rolling high-strength cold-rolled steel through a rolling die, and the cost price of the cold-rolled steel is 0.3-0.4 time that of aluminum alloy, so that the cost of the battery pack can be greatly reduced, and the production efficiency of manufacturing is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and in particular to a low-cost power battery pack structure. Background Art

[0002] In the automotive industry, new energy vehicles have developed rapidly. As the "heart" of new energy vehicles, the development of power batteries in terms of technology is of great significance to the new energy industry and the automotive manufacturing industry. With the development of power batteries, the same type of battery pack needs to be equipped with different models, making it a platform product has become the main demand of major car companies. This means that power battery packs will become more and more sophisticated and compact, and the internal space of the envelope will become less and less. This requires efficient use of the internal space of the battery pack. With the continuous increase in the manufacturing cost of the whole vehicle, how to make the power battery lower in manufacturing cost while meeting the ever-increasing performance requirements has become a problem that major car companies and battery pack manufacturers are paying more and more attention to. Utility Model Content

[0003] Based on this, it is necessary to address the technical issue of how to make the battery pack cost lower. The utility model provides a low-cost power battery pack structure.

[0004] The utility model provides a box body, which comprises a frame and a bottom plate connected with the bottom of the frame. The frame and the bottom plate are both made of high-strength cold-rolled steel through rolling.

[0005] The frame and bottom plate of the box body of the utility model are both made of high-strength cold-rolled steel through rolling dies. The cost of cold-rolled steel is 0.3-0.4 times that of aluminum alloy, which can greatly reduce the cost of the battery pack and improve the production efficiency.

[0006] As a further improvement of the above-mentioned scheme of the utility model, the frame includes two longitudinal beams made of high-strength cold-rolled steel by rolling and two transverse beams made of high-strength cold-rolled steel by rolling. The two transverse beams are respectively arranged at both ends of the longitudinal beams and the two ends of the two transverse beams are respectively welded to the two ends of the two longitudinal beams.

[0007] As a further improvement of the above solution of the utility model, a plurality of lifting ears are welded on the sides of the two longitudinal beams away from each other, and the lifting ears are formed by bending cold-rolled steel and welded to the longitudinal beams.

[0008] As a further improvement of the above solution of the utility model, a main locating pin is welded on a lifting lug of one longitudinal beam, and a secondary locating pin is welded on a lifting lug of another longitudinal beam.

[0009] As a further improvement of the above solution of the utility model, the low-cost power battery pack structure also includes a liquid cooling plate, which is arranged in the box body and fixed to the bottom plate by positioning screws.

[0010] As a further improvement of the above solution of the utility model, a plurality of bottom supporting foams are pasted on the bottom of the liquid cooling plate, and the plurality of bottom supporting foams are all in contact with the bottom plate.

[0011] As a further improvement of the above-mentioned scheme of the utility model, the liquid cooling plate includes a liquid cooling upper plate and a liquid cooling lower plate arranged up and down, a liquid cooling groove is formed on the top surface of the liquid cooling lower plate, the liquid cooling upper plate and the liquid cooling lower plate are welded as a whole to seal the liquid cooling groove, and a water inlet pipe and a water outlet pipe connected to the liquid cooling groove are connected to the liquid cooling upper plate, and the ends of the water inlet pipe and the water outlet pipe away from the liquid cooling upper plate are respectively connected to a water inlet and a water outlet, and the water inlet and the water outlet are on the frame of the box body.

[0012] As a further improvement of the above solution of the utility model, the low-cost power battery pack structure further includes:

[0013] The module assembly includes two battery modules arranged in a box and a high-voltage copper busbar for connecting the two battery modules in series. The bottoms of the two battery modules are connected to the liquid cooling plate through thermal conductive glue and fixed to the bottom plate through multiple tie rods;

[0014] a mica board disposed above the module assembly; and

[0015] The upper cover is located above the mica board and bonded to the mica board, and is sealed and connected to the top of the outer frame of the box body through bolts.

[0016] As a further improvement of the above solution of the utility model, a plurality of top supporting foams are bonded to the bottom of the mica board, and the plurality of top supporting foams are all in contact with the battery module.

[0017] As a further improvement of the above solution of the utility model, the upper cover is formed by stamping of steel plate.

[0018] Compared with the prior art, the utility model has the following beneficial effects:

[0019] 1. The frame and bottom plate of the box body of the utility model are made of high-strength cold-rolled steel by rolling through a rolling die. The cost price of cold-rolled steel is 0.3-0.4 times that of aluminum alloy, which can greatly reduce the cost of the battery pack and improve the production efficiency.

[0020] 2. The liquid cooling plate of the utility model abandons the traditional design of two liquid cooling plates and adopts a whole large liquid cooling plate to fully cover the battery cells in each module. It is connected to the water inlet and outlet on the box through the water inlet pipe and the water outlet pipe respectively, which greatly reduces the number of pipes used, thereby achieving the purpose of reducing costs and improving space utilization.

[0021] 3. The module assembly of the utility model is composed of two battery modules fixed in the module mounting beam holes of the rolled steel box body by pull rods. The two battery modules are connected in series through a high-voltage copper busbar to form a loop, which greatly reduces the number of copper busbars connected in series between modules and greatly reduces the cost of the battery pack.

[0022] 4. The utility model adds CR top support foam at the bottom of the mica board to support the upper cover. At the same time, a gap is left between the upper cover and the module to prevent the upper cover from being broken due to thermal runaway of the module assembly, so that the rigidity of the upper cover is greatly improved, which can effectively resist the impact caused by collision and extrusion and ensure the safety of users and battery packs. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of a low-cost battery pack structure proposed in an embodiment of the utility model;

[0024] Figure 2 A schematic diagram of the structure of a box in a low-cost battery pack structure proposed in an embodiment of the utility model;

[0025] Figure 3 A top view of a liquid cooling plate in a low-cost battery pack structure proposed in an embodiment of the utility model;

[0026] Figure 4 A bottom view of a liquid cooling plate in a low-cost battery pack structure proposed in an embodiment of the utility model;

[0027] Figure 5 A schematic structural diagram of a mica board in a low-cost battery pack structure proposed in an embodiment of the utility model.

[0028] Figure numerals: 1. Box body; 11. Bottom plate; 12. Longitudinal beam; 13. Transverse beam; 14. Lifting ear; 15. Main positioning pin; 16. Auxiliary positioning pin; 2. Liquid cooling plate; 21. Liquid cooling upper plate; 22. Liquid cooling lower plate; 23. Water inlet pipe; 24. Water outlet pipe; 25. Water inlet; 26. Water outlet; 27. Bottom supporting foam; 3. Module assembly; 4. Mica board; 41. Top supporting foam; 5. Upper cover; 6. Positioning screw; 7. Pull rod. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0030] It should be noted that when a component is referred to as being "mounted on" another component, it may be directly on the other component or there may be a central component. When a component is considered to be "set on" another component, it may be directly set on the other component or there may be a central component at the same time. When a component is considered to be "fixed to" another component, it may be directly fixed on the other component or there may be a central component at the same time.

[0031] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the technical field of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "or / and" used herein includes any and all combinations of one or more related listed items.

[0032] Reference Figure 1 This embodiment proposes a low-cost power battery pack structure, including a box body 1, and may also include a liquid cooling plate 2, a module assembly 3, a mica board 4 and an upper cover 5.

[0033] Combination Figure 2The box body 1 includes a frame and a bottom plate 11. The frame includes two longitudinal beams 12 and two transverse beams 13. The two longitudinal beams 12 are arranged in parallel and opposite to each other. The two transverse beams 13 are arranged in parallel and opposite to each other and the two transverse beams 13 are respectively arranged at both ends of the longitudinal beams 12. Both ends of the two transverse beams 13 are respectively welded to the two ends of the two longitudinal beams 12. The bottom plate 11 is arranged at the bottom of the frame and the bottoms of the longitudinal beams 12 and the transverse beams 13 are connected to the bottom plate 11. In this embodiment, the longitudinal beams 12, the transverse beams 13 and the bottom plate 11 are all formed into cross-sectional profiles by rolling with a rolling die using high-strength cold-rolled steel. Each cross-sectional profile has a closed cavity inside. The cost price of cold-rolled steel is 0.3-0.4 times that of aluminum alloy. This can greatly reduce the cost of the battery pack and improve the production efficiency of the production. In this embodiment, high-strength cold-rolled steel can be DP780, HC340, etc., wherein the two longitudinal beams 12 share a set of rolling dies, and the two transverse beams 13 share a set of rolling dies. In this embodiment, three lifting ears 14 are connected to the sides of the two longitudinal beams 12 away from each other, and all the lifting ears 14 are formed by bending cold-rolled steel and fixed to the frame of the box body 1 by welding. A main positioning pin 15 is connected to the lifting ear 14 in the middle of one longitudinal beam 12 by welding, and a secondary positioning pin 16 is connected to a lifting ear 14 at the end of another longitudinal beam 12 by welding. The main positioning pin 15 and the secondary positioning pin 16 facilitate the matching of the battery pack and the vehicle during the later assembly process.

[0034] The liquid cooling plate 2 is arranged inside the box 1, and Figure 3 , Figure 4 The liquid cooling plate 2 includes a liquid cooling upper plate 21 and a liquid cooling lower plate 22 arranged up and down. A liquid cooling groove is formed on the top surface of the liquid cooling lower plate 22, and a plurality of bottom supporting foams 27 are bonded to the bottom of the liquid cooling lower plate 22, and the bottom supporting foams 27 are in contact with the bottom plate 11. The liquid cooling upper plate 21 and the liquid cooling lower plate 22 are welded together to seal the liquid cooling groove, and the liquid cooling upper plate 21 is connected with a water inlet pipe 23 and a water outlet pipe 24 connected with the liquid cooling groove, and the ends of the water inlet pipe 23 and the water outlet pipe 24 away from the liquid cooling upper plate 21 are respectively connected with a water inlet 25 and a water outlet 26, and the water inlet 25 and the water outlet 26 are both on the frame of the box body 1. This embodiment abandons the traditional design of two liquid cooling plates 2, and adopts a whole large liquid cooling plate 2 to fully cover the battery cells in each module, and connects to the water inlet 25 and the water outlet 26 on the box body 1 through the water inlet pipe 23 and the water outlet pipe 24, which greatly reduces the number of pipes used, achieving the purpose of reducing costs and improving space utilization. In this embodiment, two diagonal holes on the liquid cooling plate 2 are penetrated, and positioning screws 6 welded to the bottom plate 11 are arranged in the waist-shaped holes, so as to realize the positioning and fixation of the liquid cooling plate 2. Liquid cooling of the battery module by the liquid cooling plate 2 can effectively avoid the problem of fire and explosion caused by excessive temperature during the operation of the battery, so that the safety of customers is guaranteed.

[0035] The module assembly 3 is arranged inside the box 1. In this embodiment, the module assembly 3 includes two battery modules and a high-voltage copper busbar for connecting the two battery modules in series. The bottoms of the two battery modules are connected to the liquid cooling plate 2 through thermal conductive adhesive and fixed to the module mounting beam holes on the bottom plate 11 through multiple tie rods 7. The two battery modules are connected in series through a high-voltage copper busbar to form a loop, which greatly reduces the number of copper busbars in series between the modules.

[0036] The mica board 4 is arranged above the module assembly 3, and is combined with Figure 5 A plurality of top supporting foams 41 are bonded to the bottom of the mica board 4 , and the plurality of top supporting foams 41 are in contact with the battery module.

[0037] The upper cover 5 is located above the mica board 4 and is bonded to the mica board 4 by 3M glue. It is sealed and connected to the top of the outer frame of the box body 1 by bolts. A CR top support foam 41 is added to the bottom of the mica board 4 to support the upper cover 5. At the same time, a gap is left between the upper cover 5 and the module to prevent the module assembly 3 from breaking through the upper cover 5 due to thermal runaway, so that the rigidity of the upper cover 5 is greatly improved, which can effectively resist the impact caused by collision and extrusion, and ensure the safety of users and battery packs. In this embodiment, the upper cover 5 is made of ultra-low carbon ultra-deep stamping steel plate, which has the characteristics of good strength and low cost.

[0038] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0039] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A low-cost power battery pack structure, comprising a box body (1), the box body (1) comprising a frame and a bottom plate (11) connected to the bottom of the frame, characterized in that: The frame and the bottom plate (11) are both made of high-strength cold-rolled steel by roller pressing; The frame comprises two longitudinal beams (12) made of high-strength cold-rolled steel by rolling, and two transverse beams (13) made of high-strength cold-rolled steel by rolling. The two transverse beams (13) are respectively arranged at two ends of the longitudinal beam (12), and both ends of the two transverse beams (13) are respectively welded to two ends of the two longitudinal beams (12).

2. The low-cost power battery pack structure according to claim 1, characterized in that: A plurality of lifting ears (14) are welded to the sides of the two longitudinal beams (12) that are away from each other. The lifting ears (14) are formed by bending cold-rolled steel and are welded to the longitudinal beams (12).

3. The low-cost power battery pack structure according to claim 2, characterized in that: A main positioning pin (15) is welded to a lifting lug (14) of one longitudinal beam (12), and a secondary positioning pin (16) is welded to a lifting lug (14) of the other longitudinal beam (12).

4. The low-cost power battery pack structure according to claim 1, characterized in that: The low-cost power battery pack structure further comprises a liquid cooling plate (2), wherein the liquid cooling plate (2) is arranged in the box body (1) and is fixed to the bottom plate (11) by means of positioning screws (6).

5. The low-cost power battery pack structure according to claim 4, characterized in that: A plurality of bottom supporting foams (27) are adhered to the bottom of the liquid cooling plate (2), and the plurality of bottom supporting foams (27) are all in contact with the bottom plate (11).

6. The low-cost power battery pack structure according to claim 4, characterized in that: The liquid cooling plate (2) comprises a liquid cooling upper plate (21) and a liquid cooling lower plate (22) which are arranged in an upper and lower manner. A liquid cooling groove is formed on the top surface of the liquid cooling lower plate (22). The liquid cooling upper plate (21) and the liquid cooling lower plate (22) are welded together to seal the liquid cooling groove. A water inlet pipe (23) and a water outlet pipe (24) which are in communication with the liquid cooling groove are connected to the liquid cooling upper plate (21). The ends of the water inlet pipe (23) and the water outlet pipe (24) which are away from the liquid cooling upper plate (21) are respectively connected to a water inlet (25) and a water outlet (26). The water inlet (25) and the water outlet (26) are both on the frame of the box body (1).

7. The low-cost power battery pack structure according to claim 1, characterized in that: The low-cost power battery pack structure also includes: A module assembly (3), comprising two battery modules arranged in a box (1) and a high-voltage copper busbar for connecting the two battery modules in series, wherein the bottoms of the two battery modules are connected to the liquid cooling plate (2) via a thermally conductive adhesive and are fixed to the bottom plate (11) via a plurality of tie rods (7); A mica plate (4) disposed above the module assembly (3); and An upper cover (5) is located above the mica board (4) and is bonded to the mica board (4), and is sealed and matched with the top of the outer frame of the box body (1) via bolts.

8. The low-cost power battery pack structure according to claim 7, characterized in that: A plurality of top supporting foams (41) are bonded to the bottom of the mica board (4), and the plurality of top supporting foams (41) are all in contact with the battery module.

9. The low-cost power battery pack structure according to claim 7, characterized in that: The upper cover (5) is formed by stamping of steel plate.

Images