WO2024148846A1

WO2024148846A1 - Battery pack and vehicle

Info

Publication number: WO2024148846A1
Application number: PCT/CN2023/118990
Authority: WO
Inventors: 赵家瑜; 胡敏艳; 聂洪强; 彭青波; 鲁志佩
Original assignee: 比亚迪股份有限公司
Priority date: 2023-01-13
Filing date: 2023-09-15
Publication date: 2024-07-18
Also published as: CN220321454U

Abstract

A vehicle, comprising a battery pack, which comprises a battery group, a tray, a first thermal insulation assembly and a second thermal insulation assembly, wherein the tray is provided with an accommodation cavity in which the battery group is arranged, and the tray is respectively provided with airflow channels at two ends; the airflow channels are in communication with the accommodation cavity, and a first thermal insulation member is provided in each airflow channel; the first thermal insulation assembly comprises an upper cover plate and a second thermal insulation member, the upper cover plate being arranged above the tray in a covering manner, and the second thermal insulation member being arranged on the side of the upper cover plate away from the tray; and the second thermal insulation assembly comprises a heat insulation member that is arranged on the side of the battery group away from the first thermal insulation assembly.

Description

Battery pack and vehicle

CROSS-REFERENCE TO RELATED APPLICATIONS

This disclosure claims priority to the Chinese patent application filed with the State Intellectual Property Office of China on January 13, 2023, with application number 202320143341.9 and title “Battery Pack and Vehicle,” the entire contents of which are incorporated by reference into this disclosure.

Technical Field

The present disclosure relates to the field of vehicle technology, and in particular to a battery pack and a vehicle.

Background technique

At present, when the battery is at extremely low temperature, the active polarized molecules inside the battery are greatly affected, seriously affecting the use and lifespan. In addition, the driving conditions of vehicles are very complex, such as high temperature, high cold, shallow water road surface, rainy days and snowy days, etc. The battery pack encounters a sudden change in temperature, which easily leads to a local temperature of the battery pack being too low, thus affecting the service life of the battery pack or destroying the activated molecules. The existing battery pack insulation measures are not effective enough.

Public Content

The present disclosure aims to solve at least one of the technical problems existing in the prior art. To this end, the present disclosure proposes a battery pack that can ensure heat control in multiple directions, reduce heat loss, and increase the service life of the battery pack.

The present disclosure further provides a vehicle.

According to the battery pack disclosed in the present invention, it includes: a battery pack; a tray, wherein a accommodating cavity is provided in the tray, wherein the battery pack is arranged in the accommodating cavity, and air flow channels are respectively provided at both ends of the tray, wherein the air flow channels are communicated with the accommodating cavity, and wherein a first thermal insulation member is provided in the air flow channel; a first thermal insulation component, wherein the first thermal insulation component includes: an upper cover plate and a second thermal insulation member, wherein the upper cover plate is covered on the top of the tray, and the second thermal insulation member is arranged on a side of the upper cover plate away from the tray; and a second thermal insulation component, wherein the second thermal insulation component includes: a heat insulation member, wherein the heat insulation member is arranged on a side of the battery pack away from the first thermal insulation member.

According to the battery pack disclosed in the present invention, by providing a first thermal insulation component, a second thermal insulation component and a heat insulating component, the first thermal insulation component can reduce heat loss in the lateral direction of the battery pack, the second thermal insulation component can reduce heat loss above the battery pack, and the heat insulating component can reduce heat loss below the battery pack, thereby ensuring heat control of the battery pack in multiple directions, reducing heat loss, allowing the battery pack to work normally under low temperature conditions, and prolonging the service life of the battery pack.

In some examples of the present disclosure, the air flow channel includes: a first channel and a second channel, the first channel is connected to the accommodating cavity, the second channel is adjacent to the first channel and is arranged on a side of the first channel away from the battery pack, and the first thermal insulation component is arranged inside the second channel.

In some examples of the present disclosure, a plurality of partitions are disposed on the inner wall of the first channel, and a multi-layer channel is formed between the plurality of partitions.

In some examples of the present disclosure, the upper cover plate is a composite material of glass fiber and polyurethane.

In some examples of the present disclosure, the battery pack further includes: a liquid cooling plate and a lower guard plate, the liquid cooling plate being disposed on a side of the battery pack away from the first insulation component, the lower guard plate being disposed on a side of the liquid cooling plate away from the battery pack, and the thermal insulation member being disposed between the liquid cooling plate and the lower guard plate.

In some examples of the present disclosure, the thermal insulation member includes: a honeycomb panel and a thermal insulation member, the honeycomb panel is arranged between the liquid cooling plate and the lower guard plate, and the thermal insulation member is arranged inside the honeycomb panel.

In some examples of the present disclosure, the battery pack further includes: an insulating member disposed between the battery pack and a side wall of the tray, and between the battery pack and the liquid cooling plate.

In some examples of the present disclosure, the battery pack further includes: a pre-tightening member, wherein the pre-tightening member is disposed on a side wall of the tray, and the battery pack abuts against the pre-tightening member.

In some examples of the present disclosure, the pre-tensioner is an MPP insulating member.

A vehicle according to the present disclosure includes: the battery pack described above.

Additional aspects and advantages of the present disclosure will be given in part in the following description and in part will be obvious from the following description or learned through practice of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or additional aspects and advantages of the present disclosure will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

FIG1 is an exploded view of a battery pack according to an embodiment of the present disclosure;

FIG2 is a schematic diagram of a first partial structure of a battery pack according to an embodiment of the present disclosure;

FIG3 is a schematic diagram of a second partial structure of a battery pack according to an embodiment of the present disclosure;

FIG4 is an enlarged view of portion A in FIG3 ;

FIG5 is a schematic diagram of a third partial structure of a battery pack according to an embodiment of the present disclosure;

FIG6 is a schematic diagram of the structure of a heat insulation member;

FIG7 is a schematic partial enlarged view of the portion A of the heat insulating member in FIG6 , wherein a partial schematic view of a honeycomb structure of a honeycomb panel and a portion of the heat insulating member inside the honeycomb panel are shown;

FIG. 8 is a schematic block diagram of a vehicle according to an embodiment of the present disclosure.

Reference numerals:
1. Battery pack;
10. battery pack; 20. tray; 21. receiving chamber; 22. air flow channel; 220. first channel; 221. second channel; 23. first heat preservation member;
30. First thermal insulation component; 31. Upper cover plate; 32. Second thermal insulation component; 40. Second thermal insulation component; 41. Liquid cooling plate; 42. Lower guard plate; 50. Thermal insulation component; 51. Honeycomb panel; 52. Thermal insulation component; 60. Insulation component; 70. Pre-tightening component; Vehicle 100.

Detailed ways

Embodiments of the present disclosure are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. Embodiments of the present disclosure are described in detail below.

A battery pack 1 according to an embodiment of the present disclosure will be described below with reference to FIGS. 1 to 6 .

As shown in FIG1 , the battery pack 1 according to the embodiment of the present disclosure includes: a battery pack 10, a tray 20, a first thermal insulation component 30 and a second thermal insulation component 40. The battery pack 10 can provide electrical energy so that the vehicle can operate normally. The tray 20 is the outer shell part of the battery pack 1, which can play the role of installation and protection. Other components of the battery pack 1 can be installed on the tray 20, and the tray 20 can protect the internal components from being damaged by contact with external objects. The first thermal insulation component 30 and the second thermal insulation component 40 can play the role of insulation, reduce the heat loss in the battery pack 1, help to keep warm, and improve thermal efficiency.

As shown in Fig. 1 to Fig. 3, there are multiple battery packs 10, and a receiving cavity 21 is provided in the tray 20. Multiple battery packs 10 are provided in the receiving cavity 21, so that multiple battery packs 10 can be better placed and fixed, so that multiple battery packs 10 can work stably, and multiple battery packs 10 are connected in series, which is convenient for arrangement, and can provide more energy, thereby improving the endurance of the vehicle. In addition, the battery pack 10 may include multiple blade batteries, and the blade batteries are divided into long blade batteries and short blade batteries according to capacity or size. The blade batteries can be arranged horizontally or vertically according to the needs of the vehicle, and the positive and negative poles are connected in an orderly manner to form a total positive and negative path. In the present disclosure, the tray 20 can be used once or reused multiple times. In addition, the tray 20 can also be used on multiple different platforms to enhance the universal effect of the tray 20.

As shown in Figures 2 and 3, both ends of the tray 20 are provided with airflow channels 22, which are connected to the accommodating chamber 21. When the battery discharges hot air, it can pass through the accommodating chamber 21 to the airflow channel 22, so that it can be discharged through the airflow channel 22. A first heat preservation member 23 is provided in the airflow channel 22. The first heat preservation member 23 has a low thermal conductivity and can play a role in heat preservation, blocking the heat source inside the battery pack 1 from being discharged into the air through the airflow channel 22, so as to better maintain the consistency of the temperature inside the battery pack 1. In addition, the first heat preservation member 23 is flame retardant and can be a glass fiber and honeycomb composite. The first heat-insulating member 23 may be heat-insulating cotton.

As shown in FIG1 , the first thermal insulation component 30 includes: an upper cover plate 31 and a second thermal insulation component 32. The upper cover plate 31 can play a covering role. The upper cover plate 31 is covered on the top of the tray 20, so that the space above the tray 20 can be closed to prevent the battery pack 10 in the tray 20 from touching the objects above and being damaged. The second thermal insulation component 32 can also play a role in heat preservation. The second thermal insulation component 32 is set on the side of the upper cover plate 31 away from the tray 20. It should be noted that part of the hot air in the battery pack 1 will be discharged from the top through the upper cover plate 31, while the second thermal insulation component 32 can block the hot air from being discharged upward, so that the inside of the battery pack 1 can work normally even under low temperature conditions. The second thermal insulation component 32 can be thermal insulation cotton.

As shown in Figures 1 and 5, the second heat preservation component 40 includes: a heat insulation member 50, which is arranged on the side of the multiple battery packs 10 away from the first heat preservation component 30. The heat insulation member 50 can play a heat insulation effect. The heat insulation member 50 is arranged on the side of the multiple battery packs 10 away from the first heat preservation component 30, that is, arranged below the multiple battery packs 10, so that the heat insulation member 50 can prevent the heat in the battery pack 1 from transferring downward. In other words, it can play a role in heat preservation for the interior of the battery pack 1, so that the battery pack 10 can work better at low temperatures.

Therefore, by providing the first thermal insulation component 23, the second thermal insulation component 32 and the thermal insulation component 50, the first thermal insulation component 23 can reduce the heat loss in the lateral direction of the battery pack 1, the second thermal insulation component 32 can reduce the heat loss above the battery pack 1, and the thermal insulation component 50 can reduce the heat loss below the battery pack 1, thereby ensuring the control of the heat of the battery pack 1 in multiple directions, reducing the heat loss, allowing the battery pack 1 to work normally under low temperature conditions, and can increase the service life of the battery pack 10.

In addition, as shown in FIG. 1 and FIG. 5 , the second heat preservation component 40 further includes: a liquid cooling plate 41 and a lower guard plate 42. The liquid cooling plate 41 is arranged on the side of the plurality of battery packs 10 away from the first heat preservation component 30. The lower guard plate 42 is arranged on the side of the liquid cooling plate 41 away from the battery pack 10. The heat insulation member 50 is arranged between the liquid cooling plate 41 and the lower guard plate 42. In other words, the liquid cooling plate 41 is arranged on the lower surface of the plurality of battery packs 10. The liquid cooling plate 41 not only supports the plurality of battery packs 10, but also cools the battery packs 10 to prevent the battery packs 10 from being damaged under high temperature and heat. Of course, the liquid cooling plate 41 can heat the battery packs 10 so that the battery packs 10 can work normally under low temperature conditions. The lower guard plate 42 is arranged below the liquid cooling plate 41. The lower guard plate 42 can support the battery pack 1 as a whole and protect the internal battery packs 10 from being damaged. The heat insulating member 50 is disposed between the liquid cooling plate 41 and the lower guard plate 42, so that the heat insulating member 50 can prevent the heat of the liquid cooling plate 41 from transferring downward, thereby allowing the heat of the liquid cooling plate 41 to transfer toward the battery pack 10, allowing the battery pack 10 to work better at low temperatures.

As shown in FIG. 4 , the air flow channel 22 includes: a first channel 220 and a second channel 221. The first channel 220 is connected to the accommodating chamber 21. The second channel 221 is adjacent to the first channel 220 and is arranged on the side of the first channel 220 away from the battery pack 10. The second channel 221 is provided with a first heat preservation member 23. That is, the second channel 221 is arranged outside the first channel, and the high-temperature gas generated by the battery can pass from the accommodating chamber 21 to the first channel 220, so that it can be discharged from the first channel 220. The second channel 221 plays an isolating role to reduce the loss of heat, and the first heat preservation member 23 is arranged inside the second channel 221. In this way, the first heat preservation member 23 can block the heat to prevent the heat from being discharged, and can prevent the hot gas from condensing in the second channel 221 to form water droplets, which can easily affect the battery pack 10. It can be understood that the second channel 221 can also be connected to the first channel 220, and there is no limitation on this.

Of course, the inner walls of the first channel 220 and the second channel 221 can be provided with multiple partitions 222, and then a multi-layer channel can be formed between the multiple partitions 222. This can not only reduce the heat conduction area, reduce the cross-sectional area of the heat transfer path, and minimize heat loss, but also reduce the overall weight of the tray 20 to achieve a lightweight effect.

It should be noted that the upper cover plate 31 is a glass fiber and polyurethane composite material, and the lower guard plate 42 is a glass fiber and steel composite material. In other words, the material of the upper cover plate 31 is a glass fiber and polyurethane composite material, and the material of the lower guard plate 42 is a glass fiber and steel composite material. The glass fiber and polyurethane composite material can be adjusted in thickness according to the safety requirements of each battery pack 1 to meet the needs of different vehicle battery packs 1. Moreover, due to the low density of the composite material, the weight of the upper cover plate 31 formed is very light, which is 4Kg-6Kg lighter than the steel plate or aluminum plate of the same volume. In addition, compared with the upper cover plate 31 made of SMC material, its strength is increased by 2 times, which improves the overall strength and toughness of the battery pack 1 and optimizes the mass energy density of the vehicle.

The lower guard plate 42 not only protects the liquid cooling plate 41, preventing the liquid cooling plate 41 from being deformed by external collision, or being broken by sharp objects, causing the liquid cooling plate 41 to leak and lose the heating or cooling function of the liquid cooling plate 41, but also the lower guard plate 42 can keep the liquid cooling plate 41 warm. The traditional lower guard plate 42 is generally made of aluminum profiles or all steel profiles, but the glass fiber and steel composite material can be used to take advantage of the low thermal conductivity of glass fiber and Steel has the characteristics of strong strength, etc. Steel and glass fiber are compounded in a certain thickness, which not only meets the requirements of strength, but also heat preservation, while reducing the weight of the lower guard plate 42 and reducing costs.

The material of the upper cover plate 31 and the lower guard plate 42 can also break through the traditional simple aluminum profile, SMC profile or steel profile to form a plate, and can also be a plate composed of glass fiber, steel, honeycomb and glass fiber. This type of plate not only meets the thermal insulation requirements, but also meets the structural strength requirements. Each material is integrated and adjusted according to the safety requirements of the envelope of each battery pack 10, thereby meeting the design of the upper cover plate 31 and the lower guard plate 42 for vehicles with different scenarios and configurations, shortening the development cycle, reducing costs, and improving product reliability and replicability.

Furthermore, as shown in Fig. 6, the heat insulating member 50 is a honeycomb aluminum member. It should be noted that the heat insulating member 50 is designed by referring to the honeycomb structure of bees, which can not only make the heat insulating member 50 lighter and reduce the cost, but also, the heat insulating member 50 is set as an aluminum member, that is, the heat insulating member 50 is made of aluminum material, which can increase the compressive strength of the heat insulating member 50 and is not easily damaged.

Specifically, as shown in Figures 6 and 7, the heat insulating member 50 includes: a honeycomb panel 51 and a heat insulating member 52, the honeycomb panel 51 is arranged between the liquid cooling plate 41 and the lower guard plate 42, and the heat insulating member 52 is arranged in the honeycomb panel 51. It should be noted that the liquid cooling plate 41 is divided into two layers, the upper liquid cooling plate 41 contacts the battery pack 10, and the lower liquid cooling plate 41 contacts the honeycomb panel 51. The upper liquid cooling plate 41 and the lower liquid cooling plate 41 are integrally formed by extrusion or casting, and a liquid flow channel is formed between the upper liquid cooling plate 41 and the lower liquid cooling plate 41, and the liquid flow channel is mainly used for the circulation of cooling liquid. The honeycomb panel 51 mainly utilizes the honeycomb structure of bees, and adopts polygonal honeycombs to be combined in a certain order to form a rectangular or cube-shaped honeycomb panel 51. The upper surface of the honeycomb panel 51 is in full contact with the liquid cooling plate 41, and the lower surface of the honeycomb panel 51 is in close contact with the lower guard plate 42. A plurality of honeycomb holes are arranged in the honeycomb panel 51, and the heat insulating member 52 can be arranged in the honeycomb holes. The heat insulating member 52 can play a role of heat insulation, preventing the heat of the liquid cooling plate 41 from transferring to the side away from the battery pack 10. At the same time, the honeycomb panel 51 can absorb the impact energy of the lower guard plate 42, reduce the external impact force on the liquid cooling plate 41, and ensure that the liquid cooling plate 41 is not damaged.

In addition, as shown in FIG1 , the battery pack 1 further includes an insulating member 60, which is disposed between the plurality of battery packs 10 and the side wall of the tray 20, and between the plurality of battery packs 10 and the liquid cooling plate 41. The insulating member 60 is disposed between the plurality of battery packs 10 and the side wall of the tray 20, and between the plurality of battery packs 10 and the liquid cooling plate 41. The insulating member 60 has the functions of high temperature resistance and insulation, and prevents the internal or external short circuit of the battery pack 1, which causes local high voltage arcing and causes fire.

According to an optional embodiment of the present disclosure, as shown in FIG. 1 and FIG. 2 , the battery pack 1 further includes: a pre-tightening member 70, which is arranged on the side wall of the tray 20, and a plurality of battery packs 10 abut against the pre-tightening member 70. That is, a plurality of battery packs 10 are arranged closely to the pre-tightening member 70, and the thickness of the pre-tightening member 70 is adjustable, and the thickness of the pre-tightening member 70 is increased or decreased according to the spacing distance between the battery pack 10 and the side wall of the tray 20. For example, when the number of battery packs 10 is small, the thickness of the pre-tightening member 70 can be increased to ensure the pre-tightening force between the pre-tightening member 70 and the side wall of the tray 20. In this way, the tray 20 can be applied to different battery packs 1, and the amount of electricity in the battery pack 1 can be adjusted by simply increasing or decreasing the thickness of the pre-tightening member 70. In addition, the density of the pre-tightening member 70 is very small, about 0.104Kg/m3, and it is compressible, and the thermal conductivity is low, only 0.0447W/mK, so that the heat loss in the battery pack 1 can be reduced.

Optionally, the thermal insulation 52 is an MPP insulation, the insulation 60 is an epoxy coating insulation, and the preload 70 is an MPP insulation. Both the thermal insulation 52 and the preload 70 are MPP insulations, which are composed of high temperature resistant materials and compressible MPP. They are not only resistant to high temperatures but also have low density, light weight, and compressibility, which can restrain the battery pack 10. The insulation 60 is an epoxy coating insulation. After the epoxy coating dries, a very thin protective film (similar to a block structure, but very thin) will be formed. It has high temperature resistance and high voltage insulation, which prevents residual substances or erupted liquid from remaining on the inner wall of the liquid cooling plate 41 or the tray 20 after thermal runaway of the battery pack 10, which can easily cause secondary runaway due to high voltage short circuit.

A vehicle 100 according to an embodiment of the present disclosure, as shown in FIG8 , includes: the battery pack 1 described in the above embodiment.

In the description of the present disclosure, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present disclosure.

In the description of the present disclosure, "first feature" and "second feature" may include one or more of the features. In the description of the present disclosure, "plurality" means two or more. In the description of the present disclosure, a first feature "above" or "below" a second feature may include the first and second features being in direct contact, or the first and second features being in contact not directly but through another feature between them. In the description of the present disclosure, a first feature "above" or "below" a second feature may include the first and second features being in direct contact, or the first and second features being in contact through another feature between them. When a feature is “on”, “above” or “over” a second feature, it includes the first feature being directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature.

In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example.

Although embodiments of the present disclosure have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present disclosure, the scope of which is defined by the claims and their equivalents.

Claims

A battery pack (1), characterized by comprising:

Battery pack (10);

A tray (20), wherein a receiving cavity (21) is provided in the tray (20), the battery pack (10) is arranged in the receiving cavity (21), air flow channels (22) are respectively provided at both ends of the tray (20), the air flow channels (22) are connected to the receiving cavity (21), and a first heat-insulating member (23) is provided in the air flow channel (22);

a first heat-insulating component (30), the first heat-insulating component (30) comprising: an upper cover plate (31) and a second heat-insulating component (32), the upper cover plate (31) being arranged above the tray (20), and the second heat-insulating component (32) being arranged on a side of the upper cover plate (31) away from the tray (20); and

A second heat preservation component (40), the second heat preservation component (40) comprising: a heat insulation component (50), the heat insulation component (50) being arranged on a side of the battery pack (10) away from the first heat preservation component (30).
The battery pack (1) according to claim 1 is characterized in that the air flow channel (22) comprises: a first channel (220) and a second channel (221), the first channel (220) is connected to the accommodating cavity (21), the second channel (221) is adjacent to the first channel (220) and is arranged on a side of the first channel (220) away from the battery pack (10), and the first thermal insulation component (23) is arranged inside the second channel (221).
The battery pack (1) according to claim 2 is characterized in that a plurality of partitions (222) are provided on the inner wall of the first channel (220), and a multi-layer channel is formed between the plurality of partitions (222).
The battery pack (1) according to any one of claims 1 to 3, characterized in that the upper cover plate (31) is a glass fiber and polyurethane composite material.
The battery pack (1) according to any one of claims 1 to 4, characterized in that it also includes: a liquid cooling plate (41) and a lower guard plate (42), the liquid cooling plate (41) being arranged on a side of the battery pack (10) away from the first insulation component (30), the lower guard plate (42) being arranged on a side of the liquid cooling plate (41) away from the battery pack (10), and the thermal insulation member (50) being arranged between the liquid cooling plate (41) and the lower guard plate (42).
The battery pack (1) according to claim 5 is characterized in that the thermal insulation member (50) comprises: a honeycomb panel (51) and a thermal insulation member (52), the honeycomb panel (51) being arranged between the liquid cooling plate (41) and the lower guard plate (42), and the thermal insulation member (52) being arranged inside the honeycomb panel (51).
The battery pack (1) according to claim 5 or 6 is characterized in that it also includes: an insulating member (60), wherein the insulating member (60) is arranged between the battery pack (10) and the side wall of the tray (20), and between the battery pack (10) and the liquid cooling plate (41).
The battery pack (1) according to any one of claims 1 to 7 is characterized in that it also includes: a pre-tightening member (70), wherein the pre-tightening member (70) is arranged on the side wall of the tray (20), and the battery pack (10) abuts against the pre-tightening member (70).
The battery pack (1) according to claim 8, characterized in that the pre-tightening member (70) is an MPP insulating member.
A vehicle (100), characterized by comprising: a battery pack (1) according to any one of claims 1 to 9.