Battery pack and vehicle

Abstract

The utility model discloses a battery pack and a vehicle, and the battery pack comprises a battery cell group which is provided with a plurality of battery cells; the intelligent high-voltage box is integrally arranged at the tops of part of the battery cell groups; the box body is used for accommodating the battery cell group and is provided with a beam structure, and at least one part of the beam structure horizontally extends to the bottom of the battery cell group so as to support part of the battery cell group; and the box cover is connected with the box body in a sealing manner to form an accommodating space for accommodating the battery cell group and the intelligent high-voltage box in an enclosing manner. According to the utility model, the mounting beam horizontally extends to the bottom of the battery cell group, so that the load is effectively transmitted, the liquid cooling plate is prevented from being completely used as the unique support, the thickness of the liquid cooling plate can be reduced, and the weight and the cost are further reduced. And the battery cell group transmits the load to the box body beam through the end plate, the heat-conducting structural adhesive and the pressing plate pressing strip, and the multiple connection has reliability, so that the safety performance of the battery pack is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium-ion battery packs, and in particular to a battery pack and a vehicle. Background Art

[0002] As the heart of new energy vehicles, the battery pack plays a key role in safety, endurance and other aspects.

[0003] When traditional battery packs are grouped, most of them are packaged into cell groups through peripheral structural parts, and then integrated into the battery box as a unit. This method has a complex structure, low volume utilization of the battery pack, and the battery cell group is generally fixed with bolts. Once the bolts are untwisted, the rigidity of the whole pack will be weakened, which is prone to safety accidents.

[0004] At present, CTP battery packs are generally fixed in place by gluing the cell group with liquid cooling plates or other methods. The integrated liquid cooling plate is integrated in the box. The cell group is mainly connected with the liquid cooling plate by gluing and pressurizing it into the box with pre-tightening force. The liquid cooling plate transfers the load to the box beam through glue. The integrated liquid cooling plate is generally made of 3 series or lower aluminum alloy with a low yield strength. In this case, in order to ensure the safety performance of the battery pack, thicker liquid cooling plate materials are often used, which makes the battery pack box heavier and is not conducive to improving the driving range. In addition, there is no fixed constraint near the top of the cell group. Under special circumstances, such as a severe side collision at high speed, the cell group may be debonded and then displaced greatly and invaded by the box, which may cause fire and explosion, posing a safety hazard. Utility Model Content

[0005] The technical problem to be solved by the utility model is how to design a battery pack box with high space utilization and safety performance.

[0006] In order to solve the above technical problems, the utility model provides a battery pack, comprising:

[0007] A battery cell group, comprising a plurality of battery cells;

[0008] An intelligent high-voltage box, integrated on the top of part of the battery cell group;

[0009] A box for accommodating the battery cell group, having a beam structure, at least a portion of which extends horizontally to the bottom of the battery cell group to support a portion of the battery cell group; and

[0010] A box cover is sealed and connected to the box body to form a storage space for accommodating the battery cell group and the intelligent high-voltage box.

[0011] Furthermore, the internal space of the box is divided into a plurality of independent installation cavities by an installation beam, a liquid cooling plate group is arranged at the bottom of the installation cavity, an extension portion horizontally extends from the bottom of the installation beam and contacts the bottom surface of the battery cell group, and the liquid cooling plate group and the extension portion jointly support the battery cell group (30).

[0012] Furthermore, the liquid cooling plate group includes a liquid cooling channel plate and a liquid cooling channel upper plate, and the liquid cooling channel upper plate is fixed to the upper surface of the liquid cooling channel plate by brazing.

[0013] Furthermore, the liquid cooling plate group is positioned by riveting with blind hole large flat washer rivet nuts, and is connected and fixed to the mounting beam by FDS nails; the contact portion between the liquid cooling plate group and the edge of the box is fixed by stir friction welding.

[0014] Furthermore, a bottom guard plate stamped into a multi-rib shape is provided at the bottom of the liquid cooling plate group.

[0015] Furthermore, the installation cavity is filled with a certain amount of thermally conductive structural adhesive, and the bottom surface of the battery cell group is bonded and fixed to the liquid cooling plate group and the extension portion through the thermally conductive structural adhesive.

[0016] Furthermore, a pressure plate strip is disposed on the top surface of the battery cell group, and foam is pasted on the contact surfaces of the pressure plate strip, the battery cell group and the box cover.

[0017] Furthermore, the intelligent high-voltage box is screwed and fixed to the mounting beam via a pressing plate installed on the mounting beam, and is insulated from the top surface of the battery cell group via the foam.

[0018] Furthermore, the intelligent high-voltage box includes a BMS and a BDU, and the box cover is designed as a convex structure at a position corresponding to the intelligent high-voltage box; wherein, the BDU includes a bottom shell and a top cover, and the bottom shell and the top cover are designed as a blister inverted structure.

[0019] A vehicle comprises a frame, wherein the frame is provided with the battery pack.

[0020] Compared with the prior art, the utility model has the following beneficial effects:

[0021] 1. By extending the mounting beam horizontally to the bottom of the battery cell group, the load is effectively transferred to avoid relying entirely on the liquid cooling plate as the only support. At the same time, the thickness of the liquid cooling plate can be reduced, thereby reducing weight and cost.

[0022] 2. The battery cell group transfers the load to the box beam through the end plate, thermal conductive structural adhesive and pressure plate strips, and the multiple connections are reliable, thereby improving the safety performance of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 An exploded view of a battery pack disclosed in an embodiment of the utility model;

[0024] Figure 2 It is a top view of the battery pack disclosed in the embodiment of the utility model, showing a top view of the battery pack with a hidden box cover;

[0025] Figure 3 It is a cross-sectional view of a battery pack disclosed in an embodiment of the utility model, showing a cross-sectional view of a battery pack with a hidden box cover;

[0026] Figure 4 An exploded view of the box disclosed in the embodiment of the utility model;

[0027] Figure 5 It is a partial schematic diagram of the box body disclosed in the embodiment of the utility model, showing a structural schematic diagram of the extension part of the mounting beam;

[0028] Figure 6 This is a schematic diagram of the structure of the BDU disclosed in the embodiment of the utility model;

[0029] Figure 7 It is a schematic diagram of the structure of the battery cell group disclosed in the embodiment of the utility model.

[0030] In the figure:

[0031] 10. Box cover;

[0032] 20. Intelligent high-voltage box; 21. BMS; 22. BDU; 22a. Bottom shell; 22b. Top cover;

[0033] 30. battery cell group; 31. battery cell; 32. battery cell group end plate; 33. pressure plate pressure strip;

[0034] 40. box body; 41. mounting cavity; 42. mounting beam; 42a. extension portion;

[0035] 50. Liquid cooling plate assembly; 51. Liquid cooling channel upper plate; 52. Liquid cooling channel plate; 53. Bottom guard plate. DETAILED DESCRIPTION

[0036] In order to make the technical scheme and technical effect of the utility model clearer, the technical scheme in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment. Obviously, the described embodiment is only a part of the embodiment of the utility model, not all of the embodiments.

[0037] refer to Figure 1 , Figure 2 and Figure 3The utility model aims to provide a battery pack with reduced weight and cost and good safety performance. The battery pack includes a box cover 10, an intelligent high-voltage box 20, a battery cell group 30, a box body 40 and a liquid cooling plate group 50 from top to bottom in the vertical direction. The following is a specific introduction to each component:

[0038] The box cover 10 is sealed and connected to the box body 40 to form a space for accommodating the battery pack 30 and the intelligent high-voltage box 20. The position of the box cover 10 corresponding to the intelligent high-voltage box 20 is designed as a convex structure. Figure 1 Such a design can reasonably avoid the intelligent high-voltage box 20 placed on the top surface of the battery cell group 30 inside the battery pack, thereby effectively using the battery pack space and greatly improving space utilization.

[0039] The smart high-voltage box 20 is integrated on the top surface of part of the battery cell group 30. The smart high-voltage box 20 is screwed and fixed to the mounting beam 42 by a pressure plate installed on the mounting beam 42, and is insulated from the top surface of the battery cell group 30 by foam. The smart high-voltage box 20 includes a BMS 21 and a BDU 22, wherein; Figure 6 , BDU22 includes a bottom shell 22a and a top cover 22b. The top cover 22b is made of PC by the blister molding process; the bottom shell 22a is made of PA66+GF25 by the injection molding process. The surface of the top cover 22b is provided with a logo to assist in assembly. The bottom shell 22a and the top cover 22b are designed as a blister inverted structure, that is, the top cover 22b is connected to the bottom shell 22a by pressing. The electrical selection in the intelligent high-voltage box 20 can select a low-profile relay, adopt surface mounting technology, and consider multifunctional integrated components at the same time, and set the installation connection point at the nearest position where the BDU22 needs to be connected, so that the copper bar material is shortened. The high-voltage copper busbar, low-voltage wiring harness bar, etc. led out of the intelligent high-voltage box 20 are arranged in the gap formed by the battery cell group 30 and the mounting beam 42, and the box cover 10 is designed to avoid it to make full use of the internal space of the battery pack.

[0040] The battery pack 30 has a plurality of battery cells 31, Figure 7, several battery cells 31 contain double-sided adhesive foam, several busbars and plastic parts. Among them, the battery cells 31 are arranged in a single row, and are bonded by double-sided adhesive foam between several battery cells 31, and the busbars are connected in series, and the two sides are collected by FPC to form a battery cell group 30. The pre-designed and produced threads of the battery cell group end plate 32 and the mounting beam 42 are connected by bolts. The top surface of the battery cell group 30 is provided with a pressure plate strip 33. The contact surface of the pressure plate strip 33 and the battery cell group 30 and the box cover 10 are all pasted with foam. The installation pressure can ensure that the battery cell group 30 is reliably bonded to the thermal conductive structure adhesive underneath. At the same time, the pressure plate strip 33 is bonded and pressed by double-sided adhesive of a buffer such as foam, which can effectively prevent the battery pack from being impacted in the Z direction or Y direction. The cell group 30 transfers the load to the mounting beam 42 through the cell group end plate 32, the heat-conducting structural adhesive, and the pressure plate strip 33. The multiple connections are reliable and improve the overall strength and stiffness of the battery pack, thereby improving the safety performance of the battery pack. The cell group 30 has multiple reliable connections in the battery pack, and the strength and stiffness meet the performance requirements. The lifting point designed in the middle of the battery pack for general large-capacity battery packs can be eliminated to reduce costs.

[0041] The box 40 is used to accommodate the battery pack 30. Figure 4 and Figure 5 The box body 40 has a beam structure, at least a portion of the beam structure extends horizontally to the bottom of the battery cell group 30 to support part of the battery cell group 30, that is, the bottom of the mounting beam extends horizontally with an extension portion 42a in contact with the bottom surface of the battery cell group 30. Furthermore, the internal space of the box body 40 is divided into a plurality of independent mounting cavities 41 by the mounting beam 42. Preferably, the profile frame of the box body 40 is welded with 6 series aluminum profiles to improve the overall strength and rigidity. The mounting beam 42 is a cross structure, and five mounting cavities 41 are provided. The mounting cavity 41 is filled with a quantitative thermal conductive structural adhesive, and the battery cell group 30 is pre-tightened to be pressurized into the box for installation. Preferably, foamed silicone is used as a sealing material between the box cover 10 and the box body 40, and bolts are used to connect them.

[0042] The liquid cooling plate group 50 is arranged at the bottom of the mounting cavity 41 and is integrated with the box body 40. The liquid cooling plate group 50 and the extension 42a of the mounting beam 42 jointly support the battery cell group 30 to avoid relying entirely on the liquid cooling plate as the only support. At the same time, the thickness of the liquid cooling plate can be reduced, that is, the weight of the battery pack can be reduced, thereby improving the cruising range. The liquid cooling plate group 50 includes a liquid cooling channel plate 52 and a liquid cooling channel upper plate 51, and the liquid cooling channel upper plate 51 is fixed to the upper surface of the liquid cooling channel plate 52 by brazing. The liquid cooling plate group 50 is positioned by riveting with a blind hole large flat washer rivet nut, and is connected and fixed to the mounting beam 42 by an FDS nail; the liquid cooling plate group 50 is fixed to the edge of the box body 40 by stir friction welding. Preferably, a bottom guard plate 53 stamped in a multi-rib shape is provided at the bottom of the liquid cooling plate group 50 to increase support for the liquid cooling plate group 50. The bottom guard plate 53 is connected to the profile frame by bolts and pre-riveted nuts, and uses foamed silicone material as a sealant to meet the mechanical protection level requirements. The bottom surface of the battery cell group 30 is bonded and fixed to the liquid cooling plate group 50 and the extension 42a of the mounting beam 42 by thermal conductive structural adhesive to effectively transfer the load.

[0043] It should be noted that a vehicle whose frame is equipped with the battery pack provided by the utility model also falls within the protection scope of the utility model.

[0044] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A battery pack, characterized in that: include: A battery cell group (30) having a plurality of battery cells (31); An intelligent high-voltage box (20) is integrated and arranged on the top surface of a portion of the battery cell group (30); A box (40) for accommodating the battery cell group (30), having a beam structure, at least a portion of the beam structure extending horizontally to the bottom of the battery cell group (30) to support a portion of the battery cell group (30); as well as A box cover (10), wherein the box cover (10) is sealed and connected to the box body (40) to enclose and form a receiving space for accommodating the battery cell group (30) and the intelligent high-voltage box (20).

2. The battery pack according to claim 1, characterized in that: The internal space of the box body (40) is divided into a plurality of independent installation cavities (41) by an installation beam (42); a liquid cooling plate group (50) is arranged at the bottom of the installation cavity (41); an extension portion (42a) is horizontally extended from the bottom of the installation beam (42) and is in contact with the bottom surface of the battery cell group (30); the liquid cooling plate group (50) and the extension portion (42a) jointly support the battery cell group (30).

3. The battery pack according to claim 2, characterized in that: The liquid cooling plate group (50) comprises a liquid cooling channel plate (52) and a liquid cooling channel upper plate (51), and the liquid cooling channel upper plate (51) is fixed to the upper surface of the liquid cooling channel plate (52) by brazing.

4. The battery pack according to claim 2, characterized in that: The liquid cooling plate group (50) is positioned by riveting with blind hole large flat washer rivet nuts, and is connected and fixed to the mounting beam (42) by FDS nails; the contact portion between the liquid cooling plate group (50) and the edge of the box (40) is fixed by stir friction welding.

5. The battery pack according to claim 2, characterized in that: The bottom of the liquid cooling plate group (50) is provided with a bottom guard plate (53) which is stamped into a multi-rib shape.

6. The battery pack according to claim 2, characterized in that: The installation cavity (41) is filled with a certain amount of heat-conducting structural adhesive, and the bottom surface of the battery cell group (30) is bonded and fixed to the liquid cooling plate group (50) and the extension portion (42a) via the heat-conducting structural adhesive.

7. The battery pack according to claim 6 or 2, characterized in that: A pressure plate strip (33) is provided on the top surface of the battery cell group (30), and foam is pasted on the contact surfaces of the pressure plate strip (33), the battery cell group (30) and the box cover (10).

8. The battery pack according to claim 7, characterized in that: The intelligent high-voltage box (20) is screwed and fixed to the mounting beam (42) via a pressure plate mounted on the mounting beam (42), and is insulated from the top surface of the battery cell group (30) via the foam.

9. The battery pack according to claim 1, characterized in that: The intelligent high-voltage box (20) comprises a BMS (21) and a BDU (22), and the box cover (10) is designed as a convex structure at a position corresponding to the intelligent high-voltage box (20); wherein the BDU (22) comprises a bottom shell (22a) and a top cover (22b), and the bottom shell (22a) and the top cover (22b) are designed as blister-shaped inverted structures.

10. A vehicle, comprising a frame, characterized in that: The vehicle frame is provided with a battery pack according to any one of claims 1-9.

Images