Lower box body of battery pack

Abstract

The utility model provides a lower box body of a battery pack, and relates to the technical field of new energy batteries. The battery pack lower box body comprises a bottom plate and a liquid cooling plate; the liquid cooling plate and the bottom plate are connected in a buckling manner and enclose a closed cavity; a flow channel cavity is formed in the liquid cooling plate; the flow channel cavity is provided with a plurality of groups of bulge structures for shunting; the lower box body of the battery pack further comprises a reinforcing part; the reinforcing part is arranged in the cavity; the top of the reinforcing part is fixedly connected with the liquid cooling plate, and the bottom is fixedly connected with the bottom plate; according to the lower box body of the battery pack provided by the utility model, the structural form of integrating the lower box body and the liquid cooling plate is adopted, so that the overall structural strength and rigidity of the lower box body and the battery pack can be enhanced, and meanwhile, the heat exchange efficiency of the liquid cooling plate can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of new energy batteries, and in particular to a lower box body of a battery pack. Background Art

[0002] With the rapid development of the electric vehicle and energy storage industries and the orderly advancement of the "carbon neutrality and carbon peak" goals, the demand and performance of new energy batteries are constantly increasing. As the core components of the electric vehicle and energy storage industries, the safety, endurance and charging efficiency of the battery system will directly affect the overall performance and service life of electric vehicles and energy storage systems.

[0003] In the prior art, the box of new energy batteries is usually composed of a lower box and an upper cover, and the lower box is usually composed of sheet metal, aluminum extrusion or cast aluminum. For liquid-cooled battery packs, the lower box and liquid cooling plate have two structural forms: independent and integrated.

[0004] The lower box and the cold plate are independent structures. Usually, the cold plate is placed in the lower box. The box is used to bear most of the weight of the battery pack, and the cold plate is used to cool or heat the power battery. This method is easy to process but the weight of the whole package is large, and there is a risk of coolant leakage due to too many internal coolant interfaces.

[0005] The structure of the lower box and the cold plate is to integrate the cold plate and the lower box into one component to prevent the coolant from leaking into the battery pack box. The specific structure is generally divided into two types: the cold plate is welded to the bottom of the lower box or the lower box is directly used as a cold plate. The method of welding the cold plate to the bottom of the lower box will result in a large amount of welding processing, and the increase in the thermal resistance of the lower box will cause the heat exchange efficiency of the cold plate and the battery cell to decrease, which is not conducive to the thermal management of the battery pack; and the method of using the lower box as a cold plate often leads to low structural strength and rigidity of the cold plate, and weak ability to resist external impact. If you want to improve the structural strength and rigidity, it will lead to a sharp increase in costs. Utility Model Content

[0006] In order to solve the deficiencies in the prior art, the utility model provides a battery pack lower box, which adopts an integrated structure of the lower box and the liquid cooling plate, which can enhance the overall structural strength and rigidity of the lower box and the battery pack, and at the same time improve the heat exchange efficiency of the liquid cooling plate.

[0007] The utility model adopts the following technical solutions.

[0008] The utility model provides a lower box body of a battery pack, comprising a bottom plate and a liquid cooling plate; the liquid cooling plate is buckled and connected to the bottom plate, and the two form a closed cavity; a flow channel cavity is arranged inside the liquid cooling plate, and the flow channel cavity is provided with a plurality of groups of protruding structures for flow diversion; the lower box body of the battery pack also includes: a reinforcing component; the reinforcing component is arranged in the cavity; the top of the reinforcing component is fixedly connected to the liquid cooling plate, and the bottom is fixedly connected to the bottom plate.

[0009] Preferably, the protrusion structure includes a first protrusion structure and a second protrusion structure, and the first protrusion structure and the second protrusion structure each include a plurality of strips protruding upward, and the length direction of each strip is parallel to the flow channel direction; the first protrusion structure and the second protrusion structure are arranged alternately.

[0010] Preferably, the first protruding structure includes five strips, the second protruding structure includes six strips, and each strip of the first protruding structure corresponds to the gap between two adjacent strips of the second protruding structure. Preferably, the bottom plate includes: a reinforcing beam, a support and a first circular hole; the reinforcing beam is arranged on the bottom plate and is located around the cavity to improve the strength and rigidity of the bottom plate; a plurality of first circular holes are arranged for installing rivet nuts; the support is arranged on the bottom plate and is located around the cavity, and the support is used to contact the chassis of the car or the steel beam of the cabinet to support the battery pack.

[0011] Preferably, the liquid cooling plate further comprises: a liquid inlet joint and a liquid outlet joint; the liquid inlet joint and the liquid outlet joint are respectively arranged on one side of the liquid cooling plate, and are both connected to the flow channel cavity; the liquid inlet joint and the liquid outlet joint are respectively used to input and output cooling liquid to the flow channel cavity.

[0012] Preferably, the liquid cooling plate further comprises: a plurality of second circular holes, the positions of the plurality of second circular holes corresponding one-to-one to the positions of the plurality of first circular holes, for allowing the rivet screw sleeves to pass through.

[0013] Preferably, the battery pack lower box further comprises: a crossbeam; the crossbeam is arranged on a side of the liquid cooling plate away from the bottom plate, and is used for installing the battery pack and improving the strength and rigidity of the liquid cooling plate.

[0014] Preferably, the cross beam comprises a front cross beam and a rear cross beam, and the front cross beam and the rear cross beam are symmetrically arranged on the front side and the rear side of the liquid cooling plate.

[0015] Preferably, the front crossbeam and the rear crossbeam have the same structure and are both provided with a third through hole. A screw sleeve is embedded in the crossbeam, and the end of the screw sleeve passes through the third through hole for fixing the battery module or battery pack.

[0016] Preferably, the base plate, liquid cooling plate, reinforcement component and cross beam are brazed to form a whole.

[0017] The beneficial effect of the utility model is that, compared with the prior art, the battery pack lower box provided by the utility model adopts a structural form in which the lower box and the cold plate are integrated, and a reinforcing component is placed in the cavity after the bottom plate and the liquid cold plate are buckled, so as to improve the structural strength and rigidity of the lower box and the battery pack as a whole. In addition, the flow channel cavity inside the liquid cold plate is provided with a convex structure, which can play a diversion role, reduce the flow channel cross section, thereby increasing the flow rate of the coolant, and then improve the heat exchange efficiency of the liquid cold plate, so that the temperature distribution of the box is more uniform, and the thermal management effect of the battery pack is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of a lower box of a battery pack provided in this application;

[0019] Figure 2 yes Figure 1 A schematic diagram of the structure of the bottom plate shown;

[0020] Figure 3 yes Figure 1 A schematic diagram of the structure of the liquid cooling plate shown;

[0021] Figure 4 yes Figure 3 The schematic diagram of the structure of the flow channel cavity inside the liquid cooling plate shown;

[0022] Figure 5 yes Figure 1 A schematic diagram of the structure of the reinforcement component shown;

[0023] Figure 6 yes Figure 1 A schematic diagram of the structure of the beam shown;

[0024] In the figure:

[0025] 10-bottom plate, 101-cavity, 102-first reinforcing beam, 103-support, 104-first circular hole, 105-screw sleeve, 106-second reinforcing beam;

[0026] 20-liquid cooling plate, 201-liquid inlet connector, 202-liquid outlet connector, 203-second circular hole, 204-flow channel cavity;

[0027] 30-Reinforcement components;

[0028] 40-front crossbeam;

[0029] 50-Rear crossbeam. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the utility model clearer, the technical solution of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. The embodiments described in this application are only part of the embodiments of the utility model, not all of them. Based on the spirit of the utility model, other embodiments obtained by ordinary technicians in this field without creative work are all within the scope of protection of the utility model.

[0031] like Figure 1 As shown, the first embodiment of the present invention provides a lower box of a battery pack. The lower box of the battery pack is composed of a bottom plate 10, a liquid cooling plate 20, a reinforcing component 30 and a crossbeam.

[0032] In a preferred but non-limiting embodiment of the present invention, the bottom plate 10, the liquid cooling plate 20, the reinforcing component 30 and the crossbeam are brazed to form a whole.

[0033] like Figure 2 As shown, a cavity 101, a first reinforcing beam 102, a second reinforcing beam 107, a waist-shaped support 103 and a first circular hole 104 are punched downward from the top of the bottom plate 10 by a mold. The first reinforcing beam 102 and the second reinforcing beam 106 are respectively arranged on the front and rear sides of the bottom plate 10 and are located around the cavity 101 to improve the structural strength and rigidity of the bottom plate 10; the support 103 is arranged as a waist-shaped structure, and the support 103 is located around the cavity 101. Multiple waist-shaped supports 103 are in contact with the chassis of the car or the steel beam of the cabinet to support the entire battery pack; multiple first circular holes 104 are used to install the rivet nuts 105.

[0034] like Figure 3 and Figure 4 As shown, the liquid cooling plate 20 includes an upper plate and a lower plate, wherein the upper plate height is about 1 mm, and the lower plate height is about 1 mm, and the two are connected as one body; the liquid cooling plate 20 is integrally connected to the top of the bottom plate 10 by snapping, so that the cavity 101 is closed by the liquid cooling plate 20 and the bottom plate 10. The top surface of the lower plate of the liquid cooling plate 20 is inflated to form a flow channel cavity 204 by an inflation process, and the bottom surface height of the flow channel cavity 204 is about 2.5 mm lower than the top surface height of the lower plate. The liquid inlet joint 201 is welded on the liquid cooling plate, and the liquid inlet joint 201 is connected to the flow channel cavity 204, and is used for the cooling liquid to enter the closed flow channel cavity 204 inside the liquid cooling plate; the liquid outlet joint 202 is welded on the liquid cooling plate, and the liquid outlet joint 201 is connected to the flow channel cavity 204, and is used for the cooling liquid to discharge the flow channel cavity 204.

[0035] Furthermore, the flow channel cavity 204 is bent in an S-shape and coiled around the lower plate of the liquid cooling plate 20. A plurality of groups of convex structures for flow diversion are arranged inside the flow channel cavity 204 along the flow channel direction.

[0036] In a preferred but non-limiting embodiment of the present invention, the protrusion structure includes a first protrusion structure and a second protrusion structure, and the first protrusion structure and the second protrusion structure each include a plurality of strips protruding upward, and the length direction of each strip is parallel to the flow channel direction; the first protrusion structure and the second protrusion structure are arranged alternately.

[0037] Further, the first protruding structure includes five long strips, the second protruding structure includes six long strips, and each long strip of the first protruding structure corresponds to a gap position between two adjacent long strips of the second protruding structure.

[0038] The top surface of the strip is flush with the top surface of the lower plate of the liquid cooling plate 20. The first protrusion structure and the second protrusion structure are arranged alternately, which can reduce the flow channel cross section, thereby increasing the flow rate of the coolant and improving the heat exchange efficiency of the liquid cooling plate.

[0039] In addition, in another embodiment of the present invention, the first protruding structure includes five long strips, and the second protruding structure also includes five long strips. Adopting this protruding structure makes the flow channel distribution more uniform, which is more conducive to processing.

[0040] Furthermore, in a preferred but non-limiting embodiment of the present invention, the liquid cooling plate 20 further includes a plurality of second circular holes 203, which are formed by die stamping, and the positions of the plurality of second circular holes 203 correspond one to one with the positions of the plurality of first circular holes 104. The rivet nut 105 passing through the first through hole of the bottom plate 10 passes through the second circular hole 203, and the battery pack cover is fixed by passing the end of the rivet nut 105 through the second circular hole 203 and the first circular hole 104 and threadedly connected with the screw, and is used to position the box seal ring and limit its compression.

[0041] like Figure 5 As shown, the reinforcing component 30 is formed by die stamping, and its top and bottom are welded to the liquid cooling plate 20 and the bottom plate 10 respectively, so as to enhance the overall strength and rigidity of the lower box.

[0042] In a preferred but non-limiting embodiment of the present invention, the reinforcing component 30 is a reinforcing plate, and the cross-section of the reinforcing plate is square-wave-shaped, so that the top and bottom surfaces of the reinforcing component 30 are provided with a plurality of grooves, and the plurality of grooves are evenly spaced and evenly arranged, and the grooves located at the top of the reinforcing component 30 and the grooves located at the bottom of the reinforcing component 30 are staggered left and right.

[0043] In a further preferred but non-limiting embodiment of the present invention, the reinforcing member 30 is a plurality of reinforcing beams uniformly arranged at equal intervals.

[0044] like Figure 6As shown, the crossbeam includes a front crossbeam 40 and a rear crossbeam 50, which are symmetrically arranged at the front and rear sides of the liquid cooling plate 20. The front crossbeam 60 and the rear crossbeam 70 have the same structure and are both provided with a third through hole. A screw sleeve is embedded in the crossbeam, and the end of the screw sleeve passes through the third through hole to fix the battery module or battery pack. At the same time, the crossbeam is used to enhance the overall structural strength and rigidity of the lower box.

[0045] It is worth noting that the use of molds to stamp out various structures and blow out flow channel cavities in the present invention is only a preferred but non-restrictive implementation method. Those skilled in the art can use other processes to obtain the same or equivalent structures, and the concepts all fall within the scope of the present invention.

[0046] The beneficial effect of the utility model is that, compared with the prior art, the battery pack lower box provided by the utility model adopts a structural form in which the lower box and the cold plate are integrated, and a reinforcing component is placed in the cavity after the bottom plate and the liquid cold plate are buckled, so as to improve the structural strength and rigidity of the lower box and the battery pack as a whole. In addition, the flow channel cavity inside the liquid cold plate is provided with a convex structure, which can play a diversion role, reduce the flow channel cross section, thereby increasing the flow rate of the coolant, and then improve the heat exchange efficiency of the liquid cold plate, so that the temperature distribution of the box is more uniform, and the thermal management effect of the battery pack is improved.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the utility model rather than to limit it. Although the utility model is described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that the specific implementation methods of the utility model can still be modified or replaced by equivalents, and any modifications or equivalent replacements that do not depart from the spirit and scope of the utility model should be included in the scope of protection of the claims of the utility model.

Claims

1. A battery pack lower box, comprising a bottom plate (10) and a liquid cooling plate (20); characterized in that: The liquid cooling plate (20) is buckled and connected to the bottom plate (10), and the two enclose a closed cavity (101); a flow channel cavity (204) is provided inside the liquid cooling plate (20), and the flow channel cavity (204) is provided with a plurality of groups of protruding structures for flow diversion; The battery pack lower box further comprises: a reinforcing component (30); the reinforcing component (30) is arranged in the cavity (101); the top of the reinforcing component (30) is fixedly connected to the liquid cooling plate (20), and the bottom is fixedly connected to the bottom plate (10).

2. The battery pack lower box according to claim 1, characterized in that: The protrusion structure includes a first protrusion structure and a second protrusion structure. The first protrusion structure and the second protrusion structure both include a plurality of strips protruding upward, and the length direction of each strip is parallel to the flow channel direction. The first protrusion structure and the second protrusion structure are arranged alternately.

3. The battery pack lower box according to claim 2, characterized in that: The first protruding structure includes five long strips, the second protruding structure includes six long strips, and each long strip of the first protruding structure corresponds to a gap position between two adjacent long strips of the second protruding structure.

4. The battery pack lower box according to claim 1, characterized in that: The bottom plate (10) comprises: a reinforcing beam, a support (103) and a first circular hole (104); The reinforcing beam is arranged on the bottom plate (10) and is located around the cavity (101) to improve the strength and rigidity of the bottom plate (10); A plurality of first circular holes (104) are provided for mounting the rivet nut (105); The support (103) is arranged on the bottom plate (10) and is located around the cavity (101). The support (103) is used to contact the chassis of the automobile or the steel beam of the cabinet to support the battery pack.

5. A battery pack lower box according to any one of claims 1 to 4, characterized in that: The liquid cooling plate (20) further comprises: a liquid inlet joint (201) and a liquid outlet joint (202); The liquid inlet joint (201) and the liquid outlet joint (202) are respectively arranged on one side of the liquid cooling plate (20), and are both connected to the flow channel cavity (204); the liquid inlet joint (201) and the liquid outlet joint (202) are respectively used to input and output cooling liquid to and from the flow channel cavity (204).

6. The battery pack lower box according to claim 5, characterized in that: The liquid cooling plate (20) further comprises: a plurality of second circular holes (203), The positions of the plurality of second circular holes (203) correspond one-to-one to the positions of the plurality of first circular holes (104), and are used for the rivet screw sleeves (105) to pass through.

7. A battery pack lower box according to any one of claims 1 to 4, characterized in that: The battery pack lower box also includes a crossbeam; the crossbeam is arranged on a side of the liquid cooling plate (20) away from the bottom plate (10) and is used to install the battery pack and improve the strength and rigidity of the liquid cooling plate.

8. The battery pack lower box according to claim 7, characterized in that: The cross beam comprises a front cross beam (40) and a rear cross beam (50), and the front cross beam (40) and the rear cross beam (50) are symmetrically arranged on the front side and the rear side of the liquid cooling plate (20).

9. The battery pack lower box according to claim 8, characterized in that: The front crossbeam (40) and the rear crossbeam (50) have the same structure and are both provided with a third through hole. A screw sleeve is embedded in the crossbeam, and the end of the screw sleeve passes through the third through hole, so as to fix the battery module or battery pack.

10. The battery pack lower box according to claim 7, characterized in that: The bottom plate (10), the liquid cooling plate (20), the reinforcing component (30) and the crossbeam are brazed to form a whole.

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