CN112993474A

CN112993474A - Battery pack lower box body and battery pack

Info

Publication number: CN112993474A
Application number: CN201911295255.4A
Authority: CN
Inventors: 周冠宇; 花黄伟; 程志刚; 席兵荣; 王明旺; 王华文
Original assignee: Sunwoda Electric Vehicle Battery Co Ltd
Current assignee: Sunwoda Electric Vehicle Battery Co Ltd
Priority date: 2019-12-16
Filing date: 2019-12-16
Publication date: 2021-06-18

Abstract

The utility model relates to a battery pack lower box body and a battery pack, wherein the battery pack lower box body comprises an annular surrounding frame (1) and a bottom plate (2), the surrounding frame (1) is connected to the bottom plate (2) to form a cavity for accommodating a battery module; a medium circulating pipeline (3) is arranged in the cavity, the medium circulating pipeline (3) is provided with a medium inlet (4) and a medium outlet (5), the medium inlet (4) and the medium outlet (5) are arranged on the outer side of the enclosing frame (1), the medium circulating pipeline (3) is bent and extended on a plane parallel to the bottom plate (2), and the ratio of the pipe height to the pipe diameter of the medium circulating pipeline (3) is 1: (1.2-6). The battery pack disclosed by the invention can realize better heat management effect and sealing effect, improve the space utilization rate and the energy density of the battery and reduce the cost.

Description

Battery pack lower box body and battery pack

Technical Field

The disclosure relates to the field of batteries, in particular to a lower box body of a battery pack and the battery pack.

Background

Currently, electric vehicles are actively developed in various countries of the world. The battery system of the electric automobile is one of three core technologies of the electric automobile, and the safety, the cruising ability and the charging efficiency of the battery system of the electric automobile directly influence the whole automobile performance and the running safety of the electric automobile.

The high-rate charge-discharge performance of the power battery gradually becomes one of the key factors for obtaining the acceptance and selection of the vehicle enterprises, and the temperature has a great influence on the charge-discharge performance of the battery. Therefore, the reasonably designed thermal management system enables the power battery to work at a proper temperature, is very important to the performance and the service life of the power battery, and plays a very important role in the safety performance of the battery core. The heating and heat dissipation functions of the conventional thermal management system for the power battery of the electric automobile are generally realized by two independent devices respectively, namely heat dissipation is realized by using a heat conduction paste or a water (air) cooling system, and heating is realized by using a PTC heating assembly or a PI heating film which is pasted outside the battery. On one hand, the mode occupies the internal space of the battery pack due to more related device materials, so that the energy density of the battery is reduced, and the cost of the battery pack is increased; on the other hand, the problems of poor heating and radiating efficiency and high failure risk exist.

Disclosure of Invention

The utility model aims at providing a box and battery package under battery package can save the inner space of battery package, improves space utilization, and has better cooling and thermal insulation performance.

To achieve the above object, a first aspect of the present disclosure: the lower box body of the battery pack comprises an annular surrounding frame and a bottom plate, wherein the surrounding frame is connected to the bottom plate to form a cavity for accommodating a battery module;

a medium circulating pipeline is arranged in the cavity and provided with a medium inlet and a medium outlet, the medium inlet and the medium outlet are arranged on the outer side of the enclosing frame, the medium circulating pipeline is bent and extended on a plane parallel to the bottom plate, and the ratio of the pipe height to the pipe diameter of the medium circulating pipeline is 1: (1.2-6).

Optionally, at least a part of the medium circulation pipeline is bent and extended in an S-shape to form a plurality of parallel pipeline sections, and the plurality of pipeline sections are uniformly arranged above the bottom plate at intervals.

Optionally, the medium circulation duct is integrally formed.

Optionally, the media inlet and the media outlet are located on the same side of the enclosure.

Optionally, a gap is formed in the enclosure frame, an adapter piece in sealing connection with the enclosure frame is arranged at the gap, two pipeline mounting holes are formed in the adapter piece, and the medium inlet and the medium outlet are respectively and hermetically mounted in one pipeline mounting hole.

Optionally, a sensor hole is further formed in the adaptor, the sensor hole is communicated with the pipeline mounting hole, and a temperature sensor is mounted in the sensor hole in a sealing mode.

Optionally, the medium circulation duct is bonded to the bottom plate through a first glue layer, and the shape of the first glue layer is the same as the cross-sectional shape of the medium circulation duct.

Optionally, the first adhesive layer is made of structural adhesive.

Optionally, a temperature equalizing plate is arranged above the medium circulating pipeline, and the temperature equalizing plate is fixedly connected with the enclosure frame.

Optionally, the medium circulation pipe is bonded to the temperature equalizing plate through a second adhesive layer, and the shape of the second adhesive layer is the same as the cross-sectional shape of the medium circulation pipe.

Optionally, the second adhesive layer is made of a heat-conducting adhesive.

Optionally, a third glue layer is arranged above the temperature equalization plate.

Optionally, the third adhesive layer is made of a heat-conducting adhesive.

Optionally, a plurality of first supporting blocks are arranged at the bottom of the temperature equalizing plate, and are used for supporting the temperature equalizing plate and enabling an interval to be formed between the temperature equalizing plate and the bottom plate, and the plurality of first supporting blocks are arranged in a gap formed by bending and extending the medium circulation pipeline.

Optionally, a plurality of the first supporting blocks are arranged along the center line of the temperature-uniforming plate, and/or a plurality of the first supporting blocks are arranged in an axisymmetric manner with the center line of the temperature-uniforming plate as an axis.

Optionally, a limiting hole matched with the first supporting block is formed in the bottom plate.

Optionally, enclose the frame including first curb plate, first end plate, second curb plate and the second end plate of end to end connection in proper order, first curb plate with be provided with first installation roof beam and second installation roof beam between the second curb plate, first installation roof beam reaches second installation roof beam respectively with first end plate is parallel, first installation roof beam reaches second installation roof beam all connects on the samming board, first installation roof beam with first end plate is connected, second installation roof beam is located on the central line of samming board.

Optionally, the media inlet and the media outlet are disposed outside of the first end plate.

Optionally, the first mounting beam and the second mounting beam are respectively provided with a protruding portion, and the protruding portion is provided with a fixing hole.

Optionally, the first mounting beam and the second mounting beam are respectively of a hollow structure.

Optionally, a third mounting beam is arranged between the first mounting beam and the second mounting beam, a fourth mounting beam is arranged between the second mounting beam and the second end plate, the third mounting beam and the fourth mounting beam are respectively parallel to the first side plate, and the third mounting beam and the fourth mounting beam are both connected to the temperature equalization plate.

Optionally, the third mounting beam and the fourth mounting beam are disposed on a center line of the temperature equalization plate.

Optionally, the first side plate and the second side plate are respectively provided with a second supporting block, the third mounting beam or the fourth mounting beam is provided with a third supporting block, the vertical heights of the second supporting block and the third supporting block are the same, and the second supporting block and the third supporting block are in a straight line.

Optionally, the second supporting block and the third supporting block are respectively provided with a fixing hole.

In a second aspect of the present disclosure: the battery pack comprises a cover plate and a lower box body of the battery pack, wherein the cover plate is covered on the surrounding frame.

Optionally, the cover plate is fixedly connected with the enclosure frame, an annular pressing piece is arranged on the cover plate, and the pressing piece is matched with the enclosure frame in shape.

Optionally, the edge of the cover plate extends downwards to form a first lower edge, the first lower edge extends outwards and horizontally to form a second lower edge, the press fitting part is formed with a flat plate and a vertical plate which are connected, the vertical plate is in contact with the first lower edge, and the flat plate is in contact with the second lower edge.

Optionally, the press-fitting member includes a corner piece and an edge piece, the corner piece is disposed at a corner portion of the cover plate, and the edge piece is disposed at an edge portion of the cover plate.

Optionally, fixing holes are respectively formed in the edge of the cover plate, the press-fitting part and the enclosure frame, and the press-fitting part, the cover plate and the enclosure frame are riveted through fixing parts.

This is disclosed through set up the medium circulating line that extends of buckling in the battery package, and this medium circulating line has special pipe height and pipe diameter and compares, but the maximum heat conduction effect of performance circulating medium realizes better cooling or heat preservation effect, is showing the space occupation proportion that has reduced medium circulating line simultaneously in high, saves the inner space of battery package, improves space utilization and battery energy density, reduce cost. The battery pack disclosed by the invention is convenient to install and maintain and has better manufacturability.

Additional features and advantages of the disclosure will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure without limiting the disclosure. In the drawings:

fig. 1 is an assembly view of a battery pack according to an embodiment;

fig. 2 is an exploded view of the battery pack of fig. 1;

FIG. 3 is a schematic structural view of a lower case of a battery pack according to an embodiment;

FIG. 4 is an exploded view of the lower case of the battery pack of FIG. 3;

fig. 5 is a schematic structural view of a frame in the lower case of the battery pack of fig. 3;

FIG. 6 is a schematic structural view of a medium circulation pipe of an embodiment;

FIG. 7 is an exploded view of the media circulation conduit of FIG. 6;

fig. 8 is a schematic view of the cover plate and press-fitting member in the battery pack of fig. 2;

FIG. 9 is an enlarged schematic view of portion A of FIG. 8;

figure 10 is an exploded view of a press of one embodiment;

fig. 11 is a schematic longitudinal sectional view of a medium circulation pipe of several embodiments.

Description of the reference numerals

1 enclose frame 2 bottom plate

3 medium circulating pipeline 4 medium inlet

5 medium outlet 6 adaptor

7 temperature sensor 8 first glue layer

9 temperature equalizing plate 10 second adhesive layer

11 third glue layer 12 first supporting block

13 first side plate 14 first end plate

15 second side plate 16 second end plate

17 first mounting beam 18 second mounting beam

19 bulge 20 third mounting beam

21 fourth mounting beam 22 second support block

23 third support block 24 cover plate

25 first lower edge of press-fitting part 26

27 second lower edge 28 plate

29 riser 30 corner fitting

31 sidepiece 32 pipe section

33 lifting lug 34 mounting bracket

35 screw 36 sealing ring

37 high-voltage electrical installation port of battery module 38

39 inlet connection 40 outlet connection

Detailed Description

The following detailed description of specific embodiments of the present disclosure is provided in connection with the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present disclosure, are given by way of illustration and explanation only, not limitation.

In the present disclosure, unless otherwise specified, use of directional terms such as "upper" and "lower" generally refer to upper and lower in the actual use or operating condition of the device, particularly in the direction of the drawing in the drawings; the terms "inner and outer" refer to the outline of the device.

The present disclosure provides a battery pack lower case and a battery pack including the same, referring to fig. 1 to 11. The battery pack comprises a cover plate 24 and a battery pack lower box body, the battery pack lower box body comprises an annular surrounding frame 1 and a bottom plate 2, and the cover plate 24 covers the surrounding frame 1.

The enclosure frame 1 is attached to the base plate 2, forming a chamber for accommodating the battery module 37. A medium circulation conduit 3 is arranged in the chamber. Under operating condition, to the interior input circulation medium of medium circulation pipeline 3, this circulation medium circulates in medium circulation pipeline 3, can effectively take away the heat of battery module when the temperature of battery module is too high, and when external temperature was lower, also can play isolated microthermal effect. Wherein, the circulation medium can be for can realizing the medium of above-mentioned purpose, for example water, and water has higher specific heat, can realize cooling and heat preservation to battery module betterly.

The medium circulating pipeline 3 is bent and extended on a plane parallel to the bottom plate 2, which is beneficial to fully improving the utilization rate of the pipeline. The ratio of the pipe height to the pipe diameter of the medium circulation pipeline 3 is 1: (1.2-6), more preferably 1: (2-4). Wherein, the pipe height and the pipe diameter of the medium circulation pipe 3 are for the size of the medium circulation pipe 3 on the longitudinal section, referring to fig. 11, the pipe height refers to the maximum longitudinal distance a of the longitudinal section of the medium circulation pipe 3, and the pipe diameter refers to the maximum transverse distance b of the longitudinal section of the medium circulation pipe 3. The shape of the medium circulation pipe 3 is not particularly limited as long as the above ratio of the pipe height to the pipe diameter is satisfied, and for example, the longitudinal section of the medium circulation pipe 3 may be rectangular, rounded rectangular, oval, kidney-shaped, inverted triangular, inverted trapezoidal, or the like (as shown in fig. 11). This is disclosed through set up the medium circulating line 3 that extends of buckling in the battery package, and set up special pipe height and pipe diameter to this medium circulating line 3 and compare, but furthest performance circulating medium's heat conduction effect realizes better cooling or heat preservation effect, is showing the space occupation proportion that has reduced medium circulating line 3 simultaneously in height, saves the inner space of battery package, improves space utilization and battery energy density, reduce cost.

The medium circulation pipeline 3 can be bent at will, and can be bent in a linear type or a curve type. The extended area of the medium circulation pipe 3 may cover the entire bottom plate 2, or at least the area where the battery module is assembled, to achieve better heat conduction and insulation effects. In an embodiment, referring to fig. 6 and 7, the medium circulation pipeline 3 is at least partially bent and extended in a (straight line) S shape to form a plurality of parallel pipeline sections 32, and the pipeline sections 32 are uniformly arranged above the bottom plate 2 at intervals. In other embodiments, the medium circulation pipe 3 may also be bent and extended in a zigzag, spiral, or the like form.

The medium circulation pipeline 3 is provided with a medium inlet 4 and a medium outlet 5, the medium inlet 4 and the medium outlet 5 are arranged on the outer side of the surrounding frame 1, and further, the medium circulation pipeline 3 is integrally formed, namely, the medium circulation pipeline 3 in the surrounding frame 1 is not provided with interfaces or joints, so that the influence on the battery module caused by liquid leakage in the battery pack can be prevented. Furthermore, the media inlet 4 and the media outlet 5 are located on the same side of the enclosure 1, facilitating docking with an external interface.

Enclose frame 1 and can be formed with a breach, breach department be equipped with enclose 1 sealing connection's of frame adaptor 6, seted up two pipeline mounting holes on the adaptor 6, medium entry 4 and medium export 5 are sealed mounting respectively in a pipeline mounting hole. The medium inlet 4 is connected with the medium outlet 5 of the inlet joint 39 and is connected with the outlet joint 40 through the adapter 6, and the inlet joint 39 and the outlet joint 40 are arranged on the outer side of the enclosure frame 1 and are used for inputting and outputting circulating media. Further, a sensor hole can be formed in the adaptor 6 and communicated with the pipeline mounting hole, a temperature sensor 7 is mounted in the sensor hole in a sealing mode, and a temperature sensing probe of the temperature sensor 7 is in contact with a circulating medium. The temperature sensor 7 can be used for monitoring the temperature of the circulating medium in real time and sending a temperature signal to a battery management system, and can also give an alarm signal when the temperature is too high or too low. The shape of the sensor hole can be designed according to the shape of the temperature sensor 7, preferably, the sensor hole is a round hole, the temperature sensor 7 can be installed in the sensor hole through adhesive glue, or the inner wall of the sensor hole can be designed into a threaded opening, the temperature sensor 7 is screwed in the threaded opening, and good sealing performance is achieved.

The material of the medium circulation pipe 3, the adaptor 6, the inlet connector 39 and the outlet connector 40 can be aluminum, so as to reduce the total weight of the battery pack. Further, the medium circulation pipe 3 may be made of Al3003, and the adaptor 6, the inlet joint 39, and the outlet joint 40 may be made of Al 6063. During preparation, the inlet joint 39 and the outlet joint 40 can be welded with the adapter 6 through argon arc welding, and the medium inlet 4 and the medium outlet 5 of the medium circulating pipeline 3 can be welded with the adapter 6 through brazing.

The medium circulation duct 3 may be bonded to the bottom plate 2 by a first glue layer 8, the shape of the first glue layer 8 being the same as the cross-sectional shape of the medium circulation duct 3. Further, the material of the first adhesive layer 8 may be structural adhesive.

In order to further enhance the heat management effect of the battery pack, a temperature equalizing plate 9 can be arranged above the medium circulating pipeline 3, and the temperature equalizing plate 9 is fixedly connected with the enclosure frame 1. The temperature equalizing plate 9 is close to the battery module 37 and used for promoting heat equalization between the battery module 37 and the medium circulating pipeline 3 and avoiding influence of severe temperature change on battery performance. The material of the temperature equalizing plate 9 can be aluminum, such as Al 6061. The medium circulation pipe 3 can be bonded with the temperature equalizing plate 9 through a second glue layer 10, and the shape of the second glue layer 10 is the same as the cross-sectional shape of the medium circulation pipe 3. Further, the material of the second adhesive layer 10 may be a heat conducting adhesive, so as to effectively transfer the heat of the temperature equalization plate 9 to the medium circulation pipe 3.

A third glue layer 11 can be arranged above the temperature equalization plate 9. The third adhesive layer 11 can transfer heat of the battery modules 37 to the vapor chamber 9, and also has a function of bonding the battery modules 37. The disposition area of the third paste layer 11 may be the same as the size of the bottom of the battery module 37. Further, the third adhesive layer 11 may be made of a heat conductive adhesive.

The shape of the temperature-uniforming plate 9 may be designed to be the same as the shape of the bottom surface of the battery module 37, and is generally rectangular. The number of the temperature equalizing plates 9 can be adjusted according to the requirement, and the temperature equalizing plates can be a whole plate or a plurality of plates with smaller areas. The bottom of the temperature-uniforming plate 9 can be provided with a plurality of first supporting blocks 12 for supporting the temperature-uniforming plate 9, and an interval is formed between the temperature-uniforming plate 9 and the bottom plate 2, so that a sufficient height space is provided for installing the medium circulating pipeline 3, the temperature-uniforming plate 9 is prevented from being directly pressed on the medium circulating pipeline 3, and the safety of the medium circulating pipeline 3 is guaranteed. A plurality of first supporting blocks 12 are arranged in the space formed by the bending and extending of the medium circulation pipe 3, namely between the adjacent pipe sections 32. Further, a plurality of first supporting blocks 12 may be disposed along a center line of the temperature-uniforming plate 9, wherein the center line of the temperature-uniforming plate 9 may include a plurality of straight lines passing through a center point of the temperature-uniforming plate 9; in addition, the plurality of first supporting blocks 12 can also be arranged in an axisymmetric manner by taking the center line of the temperature-uniforming plate 9 as an axis, so that effective support is achieved.

In an embodiment, the bottom plate 2 can be provided with a limiting hole matched with the first supporting block 12, when the battery pack is assembled, the first supporting block 12 is inserted into the corresponding limiting hole, and then welding is performed, so that the temperature-equalizing plate 9 is fixedly connected with the bottom plate 2, the overall strength is enhanced, and the temperature-equalizing plate 9 is prevented from generating overlarge deformation and abnormal sound in the vibration process. In another embodiment, the first support block 12 may be directly welded from the outer side (bottom) of the base plate 2 without forming a stopper hole in the base plate 2.

Enclose frame 1 and can include first curb plate 13, first end plate 14, second curb plate 15 and the second end plate 16 of end to end connection in proper order, the tip of adjacent curb plate and end plate all can be designed to be the tangent plane that is 45 jiaos with respective extending direction, two liang mutually support to adopt friction stir welding in cooperation department, form the frame 1 that encloses of rectangle. The first side plate 13, the first end plate 14, the second side plate 15 and the second end plate 16 can adopt structures connected by triangular staggered ribs, and are manufactured by adopting an aluminum extrusion molding process respectively, so that the weight is reduced and the material is saved on the premise of ensuring the mechanical strength and the rigidity. The first side plate 13, the first end plate 14, the second side plate 15 and the second end plate 16 may be welded by friction stir welding to form the enclosure frame 1. The medium inlet 4 and the medium outlet 5 may be arranged outside the first end plate 14.

Further, a first mounting beam 17 and a second mounting beam 18 may be disposed between the first side plate 13 and the second side plate 15, the first mounting beam 17 and the second mounting beam 18 are parallel to the first end plate 14, and both the first mounting beam 17 and the second mounting beam 18 are connected to the temperature equalizing plate 9. The first mounting beam 17 is connected to the first end plate 14 and the second mounting beam 18 is located on the midline of the vapor chamber plate 9. A third mounting beam 20 can be arranged between the first mounting beam 17 and the second mounting beam 18, a fourth mounting beam 21 is arranged between the second mounting beam 18 and the second end plate 16, the third mounting beam 20 and the fourth mounting beam 21 are respectively parallel to the first side plate 13, and the third mounting beam 20 and the fourth mounting beam 21 are also connected to the temperature equalizing plate 9. Further, the third mounting beam 20 and the fourth mounting beam 21 may be disposed on a center line of the vapor chamber plate 9. In addition, a fifth mounting beam may be provided on the second end plate 16, and the fifth mounting beam may be integrally formed on the second end plate 16. The first mounting beam 17, the second mounting beam 18 and the fifth mounting beam can be respectively provided with a convex part 19, and the convex part 19 is provided with a fixing hole for connecting with a fixing bolt of the battery module 37, so that the battery module 37 can be fixedly mounted and the mechanical strength of the lower box body of the battery pack can be enhanced; the number of the projections 19 may be plural, and the plural projections 19 are uniformly spaced on one mounting beam. The first mounting beam 17, the second mounting beam 18 and the fifth mounting beam can be respectively of a hollow structure, so that the total weight of the battery pack is reduced. Through setting up first installation roof beam 17, second installation roof beam 18, third installation roof beam 20, fourth installation roof beam 21 and fifth installation roof beam, can install battery module 37 in the battery package steadily, strengthen the mechanical strength of box under the battery package and the roughness of temperature-uniforming plate 9, avoid producing the abnormal sound among the vibration process.

The first mounting beam 17 may be welded to the inner side of the first end plate 14 by friction stir welding, and the second mounting beam 18 may be welded to the first side plate 13 and the second side plate 15 at both ends by friction stir welding, respectively. The first mounting beam 17, the second mounting beam 18 and the fifth mounting beam on the second end plate 16 can be welded to the vapor chamber plate 9 by friction stir welding. Two ends of the third mounting beam 20 can be respectively welded with the first mounting beam 17 and the second mounting beam 18 in an argon arc welding manner, two ends of the fourth mounting beam 21 can be respectively welded with the second mounting beam 18 and the second end plate 16 in an argon arc welding manner, and bottoms of the third mounting beam 20 and the fourth mounting beam 21 are welded on the uniform temperature plate 9 in an argon arc welding manner. The first mounting beam 17, the second mounting beam 18, the third mounting beam 20, the fourth mounting beam 21 and the fifth mounting beam are made of aluminum, such as Al6061, respectively, so that the total weight of the battery pack is reduced.

A battery management system is generally required to be arranged in the battery pack and used for monitoring the service state of the battery and protecting the use safety of the battery. In order to stably mount the battery management system, the first side plate 13 and the second side plate 15 may be respectively provided with a second supporting block 22, the third mounting beam 20 or the fourth mounting beam 21 may be provided with a third supporting block 23, upper surfaces of the second supporting block 22 and the third supporting block 23 are on the same plane, that is, vertical heights of the second supporting block 22 and the third supporting block 23 are the same, and the second supporting block 22 and the third supporting block 23 are on a straight line, so as to form a mounting and supporting component of the battery management system. Further, the second supporting block 22 and the third supporting block 23 may be respectively provided with a fixing hole for connecting with a fixing bolt of the battery management system. The second supporting block 22 and the third supporting block 23 can be welded and fixed on the required positions of the first side plate 13, the second side plate 15, the third mounting beam 20 or the fourth mounting beam 21 respectively by adopting an argon arc welding mode.

Besides the above components, the enclosure frame 1 may also be provided with other components for implementing functions such as installation. For example, 2 lifting lugs 33 may be provided at the outer side of the first end plate 14 for mounting the battery pack in an external device; the first end plate 14 may also begin with a high voltage electrical mounting port 38, and so on. These components may be designed as desired and will not be described further herein. The enclosure frame 1 can be welded with the bottom plate 2 by means of friction stir welding.

The cover plate 24 is fixedly connected with the enclosure frame 1. In order to improve the connection stability, the cover plate 24 may be provided with an annular press-fitting member 25, and referring to fig. 8 to 10, the press-fitting member 25 matches with the shape of the enclosure frame 1 to provide a downward pressure at the connection portion, so that the cover plate 24 and the lower case of the battery pack are more uniformly pressed. The cover plate 24 can be riveted with the enclosure frame 1, and at this time, the edge of the cover plate 24, the press fitting piece 25 and the enclosure frame 1 are respectively provided with a fixing hole for riveting the press fitting piece 25, the cover plate 24 and the enclosure frame 1 through a fixing piece.

In one embodiment, the edge of the cover plate 24 extends downward to form a first lower edge portion 26, and the first lower edge portion 26 extends outward horizontally to form a second lower edge portion 27, i.e. the edge of the cover plate 24 is formed in an "L" shape. Accordingly, the press-fitting member 25 is formed with the flat plate 28 and the vertical plate 29 connected, i.e. both "L" shaped, so that when assembled, the vertical plate 29 contacts the first lower edge 26 and the flat plate 28 contacts the second lower edge 27, which is advantageous for further improving the strength of the press-fitting member 25 and the stability of the connection of the cover plate 24 to the enclosure 1.

In one embodiment, the press-fitting members 25 may include corner members 30 and side members 31. The corner pieces 30 are formed in a right-angled shape and are provided at four corners of the cover plate 24; the side members 31 are formed in a long strip shape and are provided at the edges of the cover plate 24, and the edges of the adjacent corner members 30 and the side members 31 are fitted. The advantage of this arrangement is that the press-fitting 25 is easier to machine and more convenient to install. When the press-fitting part 25 needs to be provided with a fixing hole, the edges of the corner piece 30 and the side piece 31 can be respectively reserved with mounting hole notches, that is, the corner piece 30 and the side piece 31 are fixed at the joint of the two by a fixing piece. In other embodiments, the press-fitting member 25 may also be integrally formed.

A sealing ring 36 can be arranged between the cover plate 24 and the enclosure frame 1 to play a good sealing role, and when the connection mode is riveting, the sealing ring 36 is correspondingly provided with a fixing hole.

According to the battery pack, the medium circulating pipeline 3 and the lower box body of the battery pack are integrated, the medium circulating pipeline 3 has a special pipe height and pipe diameter ratio, the internal space of the battery pack can be effectively saved, the energy density is improved, and meanwhile, the cost is reduced. Medium circulating line 3 is the extension of buckling in the box down, has fully improved the utilization ratio of pipeline, and the heat dissipation is high with heating efficiency, reduces the risk that the circulating medium revealed, and the reliability is high. In addition, this disclosed battery package still has the installation of being convenient for and maintains, lightweight, advantages such as manufacturability good.

The preferred embodiments of the present disclosure are described in detail with reference to the accompanying drawings, however, the present disclosure is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present disclosure within the technical idea of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

It should be noted that the various features described in the above embodiments may be combined in any suitable manner without departing from the scope of the invention. In order to avoid unnecessary repetition, various possible combinations will not be separately described in this disclosure.

In addition, any combination of various embodiments of the present disclosure may be made, and the same should be considered as the disclosure of the present disclosure, as long as it does not depart from the spirit of the present disclosure.

Claims

1. The lower box body of the battery pack is characterized by comprising an annular surrounding frame (1) and a bottom plate (2), wherein the surrounding frame (1) is connected to the bottom plate (2) to form a cavity for accommodating a battery module;

a medium circulating pipeline (3) is arranged in the cavity, the medium circulating pipeline (3) is provided with a medium inlet (4) and a medium outlet (5), the medium inlet (4) and the medium outlet (5) are arranged on the outer side of the enclosing frame (1), the medium circulating pipeline (3) is bent and extended on a plane parallel to the bottom plate (2), and the ratio of the pipe height to the pipe diameter of the medium circulating pipeline (3) is 1: (1.2-6).

2. The battery pack lower case body according to claim 1, wherein the medium circulation duct (3) is at least partially bent and extended in an S-shape to form a plurality of parallel duct sections (32), and the plurality of duct sections (32) are uniformly spaced above the bottom plate (2).

3. The lower case of battery pack according to claim 1, wherein the medium circulation duct (3) is integrally formed.

4. The battery pack lower box body according to claim 1, wherein a gap is formed in the surrounding frame (1), an adapter (6) connected with the surrounding frame (1) in a sealing manner is arranged at the gap, two pipeline mounting holes are formed in the adapter (6), and the medium inlet (4) and the medium outlet (5) are respectively mounted in one pipeline mounting hole in a sealing manner.

5. The lower box body of the battery pack as claimed in claim 4, wherein the adaptor (6) is further provided with a sensor hole, the sensor hole is communicated with the pipeline mounting hole, and a temperature sensor (7) is hermetically mounted in the sensor hole.

6. The lower box body of the battery pack as claimed in claim 1, wherein the medium circulation duct (3) is bonded to the bottom plate (2) by a first glue layer (8), and the shape of the first glue layer (8) is the same as the cross-sectional shape of the medium circulation duct (3);

furthermore, the first adhesive layer (8) is made of structural adhesive.

7. The lower box body of the battery pack as claimed in claim 1, wherein a temperature-equalizing plate (9) is arranged above the medium circulating pipeline (3), and the temperature-equalizing plate (9) is fixedly connected with the enclosure frame (1).

8. The lower box body of the battery pack according to claim 7, wherein the medium circulation duct (3) is bonded to the temperature equalizing plate (9) through a second adhesive layer (10), and the shape of the second adhesive layer (10) is the same as the cross-sectional shape of the medium circulation duct (3);

furthermore, the second adhesive layer (10) is made of heat-conducting adhesive.

9. The lower box body of the battery pack as claimed in claim 7, wherein a third glue layer (11) is arranged above the temperature equalizing plate (9);

furthermore, the third adhesive layer (11) is made of heat-conducting adhesive.

10. The lower box body for the battery pack according to claim 7, wherein a plurality of first supporting blocks (12) are arranged at the bottom of the temperature equalizing plate (9) and used for supporting the temperature equalizing plate (9) and enabling the temperature equalizing plate (9) to be spaced from the bottom plate (2), and the plurality of first supporting blocks (12) are arranged in a gap formed by bending and extending the medium circulating pipeline (3).

11. The lower case for battery packs as claimed in claim 10, wherein a plurality of the first support blocks (12) are disposed along a center line of the temperature-uniforming plate (9), and/or a plurality of the first support blocks (12) are disposed axisymmetrically with respect to the center line of the temperature-uniforming plate (9).

12. The lower box body of the battery pack as claimed in claim 10, wherein the bottom plate (2) is provided with a limiting hole matched with the first supporting block (12).

13. The lower box body for the battery packs as claimed in claim 7, wherein the enclosure frame (1) comprises a first side plate (13), a first end plate (14), a second side plate (15) and a second end plate (16) which are sequentially connected end to end, a first mounting beam (17) and a second mounting beam (18) are arranged between the first side plate (13) and the second side plate (15), the first mounting beam (17) and the second mounting beam (18) are respectively parallel to the first end plate (14), the first mounting beam (17) and the second mounting beam (18) are both connected to the temperature equalizing plate (9), the first mounting beam (17) is connected to the first end plate (14), and the second mounting beam (18) is located on the center line of the temperature equalizing plate (9);

further, the medium inlet (4) and the medium outlet (5) are arranged outside the first end plate (14).

14. The lower box body of the battery pack as claimed in claim 13, wherein the first mounting beam (17) and the second mounting beam (18) are respectively provided with a protruding part (19), and the protruding parts (19) are provided with fixing holes; and/or the presence of a gas in the gas,

the first mounting beam (17) and the second mounting beam (18) are respectively of a hollow structure.

15. The lower box body for the battery pack according to claim 13, wherein a third mounting beam (20) is arranged between the first mounting beam (17) and the second mounting beam (18), a fourth mounting beam (21) is arranged between the second mounting beam (18) and the second end plate (16), the third mounting beam (20) and the fourth mounting beam (21) are respectively parallel to the first side plate (13), and the third mounting beam (20) and the fourth mounting beam (21) are both connected to the temperature equalizing plate (9);

further, the third mounting beam (20) and the fourth mounting beam (21) are arranged on the center line of the temperature equalizing plate (9).

16. The lower box body for the battery pack according to claim 15, wherein the first side plate (13) and the second side plate (15) are respectively provided with a second supporting block (22), the third mounting beam (20) or the fourth mounting beam (21) is provided with a third supporting block (23), the vertical heights of the second supporting block (22) and the third supporting block (23) are the same, and the second supporting block (22) and the third supporting block (23) are in a straight line;

furthermore, fixing holes are respectively formed in the second supporting block (22) and the third supporting block (23).

17. A battery pack, comprising a cover plate (24) and the lower case of the battery pack as claimed in any one of claims 1 to 16, wherein the cover plate (24) is covered on the surrounding frame (1).

18. The battery pack according to claim 17, wherein the cover plate (24) is fixedly connected to the enclosure frame (1), and an annular press fitting (25) is disposed on the cover plate (24), wherein the press fitting (25) matches the shape of the enclosure frame (1).

19. The battery pack according to claim 18, wherein the edge of the cover plate (24) extends downward to form a first lower edge (26), the first lower edge (26) extends outward horizontally to form a second lower edge (27), the press fitting (25) is formed with a flat plate (28) and a riser (29) connected, the riser (29) is in contact with the first lower edge (26), and the flat plate (28) is in contact with the second lower edge (27).

20. The battery pack according to claim 18 or 19, wherein the press-fitting member (25) comprises a corner piece (30) and an edge piece (31), the corner piece (30) being provided at a corner of the lid plate (24), and the edge piece (31) being provided at an edge of the lid plate (24).

21. The battery pack according to claim 18 or 19, wherein fixing holes are respectively formed in the edge of the cover plate (24), the press-fitting member (25) and the enclosure frame (1) for riveting the press-fitting member (25), the cover plate (24) and the enclosure frame (1) by a fixing member.