CN113437427A

CN113437427A - Battery system and vehicle

Info

Publication number: CN113437427A
Application number: CN202010146327.5A
Authority: CN
Inventors: 商光路
Original assignee: Audi AG
Current assignee: Audi AG
Priority date: 2020-03-05
Filing date: 2020-03-05
Publication date: 2021-09-24

Abstract

Provided are a battery system for a vehicle and the vehicle. The battery system comprises a shell, a battery stack and an exhaust guide device. The battery stack includes a plurality of battery cells. The exhaust guide device is arranged above the cell stack and comprises a body and a plurality of covering pieces, wherein the body and the covering pieces are fixedly arranged above the cell stack relative to the shell. The body is provided with a plurality of holes corresponding to the plurality of battery cells. The plurality of covers correspond to the plurality of holes, and each cover covers the corresponding hole on the upper side of the body, wherein the size of the cover is larger than the size of the corresponding hole. According to the scheme of the invention, the battery cell without thermal runaway can be protected from the high-temperature high-pressure gas generated by the battery cell with thermal runaway.

Description

Battery system and vehicle

Technical Field

The present invention relates to the field of vehicle technology, and more particularly, to a battery system for a vehicle and a vehicle having the same.

Background

With the development of vehicle technology, the demand for the safety performance of a battery system of a vehicle is also increasing. If the temperature of a certain battery monomer is too high in the battery system, abnormal thermal runaway is easy to occur, a large amount of high-temperature high-pressure gas is generated, and the high-temperature high-pressure gas is gathered in a shell of the battery system and easily contacts the battery monomer which is not subjected to thermal runaway, so that other battery monomers which are not subjected to thermal runaway are damaged.

Accordingly, it is desirable to provide a battery system for a vehicle and a vehicle having the same to at least partially solve the problems in the prior art.

Disclosure of Invention

To solve the above technical problems, according to an aspect of the present invention, a battery system for a vehicle is provided. The battery system comprises a shell, a battery stack and an exhaust flow guide device. The housing has an interior cavity. The cell stack is disposed in the internal cavity, the cell stack including a plurality of cells. The exhaust guide device is arranged above the cell stack and comprises a body and a plurality of covering pieces. The body is fixedly arranged above the cell stack relative to the shell, and the body is provided with a plurality of holes corresponding to the plurality of battery cells. The plurality of covers correspond to the plurality of holes, and each cover covers the corresponding hole on the upper side of the body, wherein the size of the cover is larger than the size of the corresponding hole.

Preferably, the cover is connected to the body.

Preferably, the battery system further comprises a biasing member fixedly disposed relative to the housing and biased against the body.

Preferably, the holes and the covering member are sized such that, when the covering member is overlaid on the holes corresponding thereto, both sides of the covering member are spaced apart from side edges of the body by a predetermined distance to form pressing portions on the body against which the pressing members are pressed.

Preferably, the battery system further includes a stack holder provided at a longitudinal end of the stack and connected to the housing, the pressing member being connected to the stack holder.

Preferably, the stack holder comprises a first support, a second support and at least one deformable component. The second support is disposed opposite to the first support in a longitudinal direction of the cell stack. The at least one deformable assembly is disposed between the first and second supports, wherein each of the deformable assemblies includes first and second bendable members bendable toward each other.

Preferably, the battery system further includes a heat transfer assembly, at least a portion of which is disposed between the cell stack and the housing, the heat transfer assembly being in thermal contact with each of the battery cells and the housing.

Preferably, the battery system includes a plurality of cell stacks, and the heat transfer assembly includes a plurality of first heat pipes and at least one second heat pipe. The first heat pipe is disposed between the cell stack and the case and extends in a longitudinal direction of the cell stack. The first heat pipe is in thermal contact with the housing and each of the cells of the cell stack. The second heat pipe is disposed between the stack holder and the case and connects a plurality of the first heat pipes, the first heat pipes being connected to the case at the connection of the first heat pipes and the second heat pipes.

Preferably, the heat transfer assembly further comprises a thermal insulator disposed between the first heat pipe and the cell stack, the thermal insulator having a width smaller than a width of any one of the first heat pipe and the battery cell, and the width of the thermal insulator decreases as a distance from the connection increases.

In another aspect of the present invention, a vehicle is provided that includes any of the battery systems described above.

According to the scheme of the invention, when any battery cell in the battery stack is subjected to thermal runaway, the thermal runaway battery cell can generate a large amount of high-temperature and high-pressure gas. The instant these high temperature and high pressure gases are ejected from the thermal runaway cell tends to be discharged upwardly through the hole in the body of the exhaust guide device corresponding to the thermal runaway cell. In this process, these high temperature and high pressure gases can exert a large upward impact force on the cover covering the corresponding hole of the body, blowing the cover away from the hole, and then discharging over the body through the hole. Thereafter, the high-temperature and high-pressure gases diffuse to a space above other battery cells around the thermal runaway battery cell above the body due to being blocked by the top wall of the case and are separated from the other battery cells by the body. For other battery cells around the thermal runaway battery cell, the covering piece covers the holes of the body corresponding to the battery cells on the upper side of the body, and the size of the covering piece is larger than that of the corresponding holes, so that the high-temperature high-pressure gas on the upper side of the body cannot blow the covering piece away from the holes downwards, and the high-temperature high-pressure gas cannot be discharged to the periphery of other battery cells without thermal runaway through the holes, thereby avoiding the high-temperature high-pressure gas from contacting other battery cells without thermal runaway, and protecting the other battery cells from being damaged by the high-temperature high-pressure gas.

Drawings

Non-limiting and non-exhaustive embodiments of the present invention are described by way of example with reference to the following drawings, in which:

fig. 1 is an exploded perspective view of a battery system according to a preferred embodiment of the present invention;

FIG. 2 is a schematic view of an exhaust flow guide of the battery system shown in FIG. 1;

fig. 3 is a schematic perspective view of a stack holder of the battery system shown in fig. 1; and

fig. 4 is a schematic top view of the stack holder shown in fig. 3.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In a first aspect of the present invention, a battery system for a vehicle is provided. Fig. 1 is an exploded perspective view of a battery system 100 according to a preferred embodiment of the present invention. Fig. 2 is a schematic view of the exhaust guide 130 of the battery system 100 shown in fig. 1. Fig. 3 is a perspective view of the stack holder 150 of the battery system 100 shown in fig. 1. Fig. 4 is a schematic top view of the stack holder 150 shown in fig. 3. The battery system 100 provided by the present invention will be described in detail with reference to fig. 1 to 4.

As shown in fig. 1 and 2, the battery system 100 includes a case 110, a cell stack 120 disposed in the case 110, and an exhaust guide 130.

As shown in fig. 1, the housing 110 has an inner cavity 111, and the inner cavity 111 may form an accommodation space to accommodate components such as the cell stack 120 of the battery system 100. Specifically, in the present embodiment, the housing 110 has a substantially box-like shape. The housing 110 includes a bottom wall 112 and a side wall 113 extending upward from a peripheral edge of the bottom wall 112. The bottom wall 112 and the side wall 113 together enclose an inner cavity 111 having an open top. In addition, the housing 110 includes a top wall 114 covering the top opening of the inner cavity 111. The bottom wall 112 and the side wall 113 may be integrally formed, and the top wall 114 may be removably coupled to the side wall 113 to facilitate positioning of components, such as the cell stack 120 of the battery system 100, within the interior cavity 111. Of course, in other embodiments of the invention not shown, the housing 110 may also be any other suitable shape.

At least a portion of the housing 110 may be made of a metallic material (e.g., iron, copper, aluminum, steel, etc.) having good thermal conductivity, which may provide good thermal conductivity, on the one hand, and mechanical strength required to support various components inside the housing 110, on the other hand. For example, in the present embodiment, at least the bottom wall 112 of the housing 110 may be made of a metal material having good thermal conductivity.

As shown in fig. 1, at least one cell stack 120 is disposed in the inner cavity 111 of the case 110. In the present embodiment, twelve cell stacks 120 are disposed in the inner cavity 111 of the housing 110. However, it is understood that any other suitable number of cell stacks 120, e.g., less than or more than twelve, may be disposed in the interior cavity 111 of the housing 110. When a plurality of cell stacks 120 are disposed in the inner cavity 111 of the housing 110, the plurality of cell stacks 120 may be connected in series to provide sufficient battery power to the vehicle.

As shown in fig. 1, each cell stack 120 includes a plurality of unit cells arranged in a longitudinal direction. The plurality of battery cells are connected together in series to be able to provide sufficient battery energy for the vehicle.

As shown in fig. 1 and 2, the exhaust guide 130 is disposed above the cell stack 120. Specifically, in the present embodiment, the exhaust guide 130 is disposed between the cell stack 120 and the top wall 114. The exhaust guide 130 includes a body 131 and a plurality of covers 132.

As shown in fig. 2, the body 131 may be formed in a plate shape. The body 131 is fixedly disposed above the cell stack 120 with respect to the case 110, so that even if a certain cell thermally runaway generates high-temperature and high-pressure gas, the high-temperature and high-pressure gas does not move the body 131. It should be noted that the term "fixed arrangement" as used herein refers to a relatively fixed arrangement, that is, a fixed position in use, and is not completely detachable. The body 131 is provided with a plurality of holes (not shown) corresponding to the plurality of battery cells. The number of holes is the same as the number of battery cells, and each hole corresponds to one of the battery cells. Each hole is located directly above its corresponding cell. When one of the battery cells is out of control due to thermal runaway, high-temperature and high-pressure gas generated due to thermal runaway can be discharged through the corresponding hole. The body 131 may be made of mica or plastic.

As shown in fig. 2, the plurality of covers 132 correspond to the plurality of holes, and each cover 132 covers the hole corresponding thereto on the upper side of the body 131. The number of the covers 132 is the same as the number of the holes. Wherein the cover 132 is larger in size than the corresponding aperture. When any one of the cells in the stack 120 is thermally runaway, the thermally runaway cell may generate a large amount of high-temperature and high-pressure gas. The high-temperature and high-pressure gas at the moment of being ejected from the thermal runaway battery cell tends to be discharged upward through the hole of the body 131 of the exhaust guide device 130 corresponding to the thermal runaway battery cell. In the process, the high-temperature and high-pressure gas applies a large upward impact force to the cover 132 covering the corresponding hole of the body 131, thereby blowing the cover 132 away from the hole and discharging the gas above the body 131 through the hole. Thereafter, the high-temperature and high-pressure gases diffuse to the space above the other cells around the thermal runaway cell above the body 131 due to being blocked by the top wall 114 of the case 110 and are separated from the other cells by the body 131. For other battery cells around the thermal runaway battery cell, since the covering member 132 covers the holes of the body 131 corresponding to the battery cells on the upper side of the body 131 and the size of the covering member 132 is larger than that of the corresponding holes, the high-temperature and high-pressure gas on the upper side of the body 131 does not blow the covering member 132 downward from the holes, and thus the high-temperature and high-pressure gas is not discharged to the periphery of other battery cells without thermal runaway through the holes, thereby preventing the high-temperature and high-pressure gas from contacting other battery cells without thermal runaway and protecting the other battery cells from the high-temperature and high-pressure gas.

In the present embodiment, each cell stack 120 is provided with one exhaust guide 130, that is, twelve exhaust guides 130 are provided in the inner cavity 111 of the housing 110.

Preferably, the cover 132 is connected to the body 131. Specifically, the cover 132 may be attached to the body 131 by gluing, welding, snap-fit connection, or other process. It should be noted that the purpose of the connecting process is not to firmly connect the cover 132 and the body 131, but to form a small bonding force between the cover 132 and the body 131 through the connecting process, the bonding force can normally fix the cover 132 and the body 131 together, but the cover 132 can be separated from the body 131 when being impacted by high-temperature and high-pressure gas. For example, a small bonding force may be formed between the cover 132 and the body 131 through a welding process such as a heat-resistant glue stick welding. High-temperature and high-pressure gas generated by thermal runaway of one battery cell can blow the covering member 132 away from the hole from the lower side of the body 131 from bottom to top, so that the gas is discharged to the upper side of the body 131 through the corresponding hole. The cover 132 may be made of mica.

As shown in fig. 1, the battery system 100 further includes a pressing member 140. The pressing member 140 is fixedly disposed with respect to the housing 110. The pressing member 140 presses against the body 131. The movement of the body 131 in the vertical direction may be restricted by the pressing members 140 and the cell stack 120, and the movement of the body 131 in the horizontal plane may be restricted by the case 110, so that the body 131 is fixed with respect to the case 110. In this manner, when thermal runaway occurs in any one of the cells in the stack 120, the body 131 is not moved by high-temperature and high-pressure gas generated due to the thermal runaway of the cell. Preferably, the pressing member 140 may be made of a metal material (e.g., iron, copper, aluminum, steel, etc.) having good heat conductivity. Therefore, on one hand, good heat conducting performance can be provided, so that the heat of the battery monomer with higher temperature can be timely transferred to other battery monomers before the battery monomer is subjected to thermal runaway, and the possibility that one battery monomer is subjected to thermal runaway due to overhigh temperature is reduced; on the other hand, the mechanical strength required to press against the body 131 can be provided.

Preferably, as shown in fig. 2, the holes and the covers 132 are sized such that, when the covers 132 are covered on the holes corresponding thereto, both sides of the covers 132 are spaced apart from side edges of the body 131 by a predetermined distance to form pressing portions (e.g., first and second

pressing portions

131A and 131B) on the body 131. It should be noted that the "side portion" described herein is with respect to the width direction of the body 131. The longitudinal direction of the body 131 is parallel to the arrangement direction of the battery cells, and the width direction of the body 131 is perpendicular to the longitudinal direction. The pressing member 140 presses against the pressing portion. That is, the press 140 is spaced apart from the cover 132. In this way, when the pressing member 140 presses against the body 131, the pressing member 140 only presses against the pressing portion, and does not press against the covering member 132, so as to avoid that the covering member 132 is obstructed by the pressing member 140 and cannot be blown away by high-temperature and high-pressure gas generated by thermal runaway of one of the battery cells. In addition, a plurality of the covers 132 are spaced apart from each other in the longitudinal direction of the body 131, so that one of the covers 132 is not interfered by the other covers 132 when being blown open by the impact of the high-temperature and high-pressure gas.

It should be noted that, when a plurality of cell stacks 120 are accommodated in the housing 110, the plurality of cell stacks 120 arranged in the longitudinal direction may share one pressing member 140, or may be respectively provided with separate pressing members 140.

As shown in fig. 1, 3, and 4, the battery system 100 further includes a stack holder 150, the stack holder 150 is disposed at a longitudinal end of the cell stack 120 and is connected to the case 110, and the pressing member 140 is connected to the stack holder 150 by means of, for example, a threaded fastener or the like, so that the pressing member 140 is fixed with respect to the case 110. Note that, as with the longitudinal direction of the body 131 mentioned above, the "longitudinal direction" or "longitudinal direction" of the cell stack also refers to a direction parallel to the arrangement direction of the battery cells. Accordingly, the "width direction" of the cell stack, which will be described hereinafter, refers to a direction perpendicular to the longitudinal direction of the cell stack 120. In the present embodiment, a stack holder 150 is provided at a longitudinal end of each cell stack 120. The stack holder 150 is coupled to the side wall 113 of the case 110. The pressing member 140 and each of the stack holders 150 are detachably connected together. Preferably, the cell stack 120 may be coupled with the stack holder 150 by an adhesive such as foam and glue to restrict movement of the cell stack 120 relative to the case 110 so that the battery cells can be aligned with the corresponding holes thereof in a more stable manner.

Alternatively, as shown in fig. 1, 3 and 4, the stack holder 150 includes a first support 151, a second support 152, and at least one deformable member 153. The first and

second supports

151 and 152 are oppositely disposed in the longitudinal direction of the cell stack 120. Alternatively, the first and

second supports

151 and 152 may be made of a metal material (e.g., iron, copper, aluminum, steel, etc.) having a good thermal conductivity. At least one deformable component 153 is disposed between the first support 151 and the second support 152, wherein each of the deformable components comprises a first bendable piece 153A and a second bendable piece 153B bendable toward each other. The first bendable member 153A and the second bendable member 153B may be made of a flexible material.

As shown in fig. 3 and 4, in the present embodiment, the stack holder 150 includes a plurality of deformable members 153. During the charging process of the battery system 100, the battery cell generates an expansion force. When the expansion force is large enough, the stack holder 150 is pressed to deform the deformable members 153 in the stack holder 150, so as to provide a suitable deformation space for the battery cells. When the first bendable member 153A and the second bendable member 153B are deformed to contact each other, the first bendable member 153A and the second bendable member 153B generate a large resistance to the expansion of the battery cells, thereby limiting a deformation space of the battery stack 120 and preventing the battery cells from being infinitely deformed. During the discharging process of the battery system 100, the swelling force generated by the battery cells will gradually decrease, and thus, the degree of deformation of the first and second bendable members 153A and 153B will gradually decrease until the first and second bendable members 153A and 153B return to their natural state. Preferably, in a natural state, the first bendable member 153A and the second bendable member 153B have bent toward each other by themselves. In this way, the deformable members 153 in the stack holder 150 are more likely to deform in a manner of bending toward each other when deformed by the expansion force of the battery cells.

As shown in fig. 1, the battery system 100 also includes a heat transfer assembly 160. At least a portion of the heat transfer assembly 160 is disposed between the cell stack 120 and the housing 110. Specifically, in the present embodiment, a portion of the heat transfer assembly 160 is disposed between the cell stack 120 and the case 110, and the other portion of the heat transfer assembly 160 is disposed between the cell stack holder 150 and the case 110. More specifically, a portion of the heat transfer assembly 160 is disposed between the cell stack 120 and the bottom wall 112 of the housing 110, and the other portion of the heat transfer assembly 160 is disposed between the cell stack holder 150 and the bottom wall 112 of the housing 110. A heat transfer assembly 160 is in thermal contact with each cell and the housing 110. Since the heat transfer assembly 160 is in thermal contact with each battery cell and the case 110, when the temperature of any one of the battery cells in the battery stack 120 is high, the heat of the high-temperature battery cell can be transferred to the heat transfer assembly 160. The heat transfer assembly 160 can transfer heat to the casing 110 and then to the outside of the casing 110 through thermal contact with the casing 110, and can transfer heat to other battery cells through thermal contact with other battery cells, so as to prevent thermal runaway caused by an excessively high temperature of one of the battery cells.

Specifically, in one embodiment of the present invention, as shown in FIG. 1, the heat transfer assembly 160 includes a plurality of first heat pipes 161 and at least one second heat pipe 162. The first heat pipe 161 is disposed between the cell stack 120 and the case 110 and extends in the longitudinal direction of the cell stack 120. One first heat pipe 161 may be provided for each cell stack 120, respectively, and one first heat pipe 161 may be shared by a plurality of cell stacks 120 arranged in the longitudinal direction. The first heat pipe 161 is in thermal contact with the case 110 and each of the battery cells of the cell stack 120. The second heat pipe 162 extends in the width direction of the cell stack 120. The second heat pipe 162 is disposed between the stack holder 150 and the case 110 and connects the plurality of first heat pipes 161. The first heat pipe 161 is connected to the case 110 at the connection of the first heat pipe 161 and the second heat pipe 162.

The first heat pipe 161 and the second heat pipe 162 have a case generally made of a metal material. The interior of the pipe shell is pumped into a negative pressure state and is filled with liquid working medium. The liquid working medium is usually a low-boiling point, volatile working medium. The tube wall of the tube shell is provided with a liquid absorption core which is made of capillary porous materials. The first heat pipe 161 and the second heat pipe 162 can combine heat conduction and vapor-liquid phase change heat transfer of the working medium, and have small heat resistance, so that the heat transfer capacity is high, and heat transfer can be rapidly carried out. When the temperature of any one of the battery cells in the battery stack 120 is high (e.g., 65 ℃ or higher and 120 ℃ or higher), the heat of the high-temperature battery cell can be rapidly transferred to the first heat pipe 161. On one hand, the first heat pipe 161 can transfer a part of heat to the casing 110 through thermal contact with the casing 110 and further to the outside of the casing 110, so that the possibility that one of the battery cells is thermally out of control due to over-high temperature is greatly reduced. On the other hand, the first heat pipe 161 can rapidly transfer another part of heat to other battery cells in the battery module where the battery cell with the higher temperature is located, so that the possibility that thermal runaway occurs to one of the battery cells due to the overhigh temperature is further reduced. On the other hand, a part of the heat may be transferred to the connection point of the other first heat pipe 161 through the first heat pipe 161 corresponding to the battery cell with the higher temperature and the second heat pipe 162 connected to the first heat pipe 161, and transferred to the battery cells in the other battery stack 120 from the connection point of the other first heat pipe 161, thereby further reducing the possibility that one of the battery cells may be thermally runaway due to the over-high temperature.

More specifically, in the present embodiment, the first heat pipe 161 is disposed between the cell stack 120 and the bottom wall 112 of the case 110. A second heat pipe 162 extending in the width direction of the cell stack 120 is provided between the cell stack holder 150 and the bottom wall 112 of the case 110. The second heat pipe 162 is connected to the first heat pipe 161 above the first heat pipe 161, and is in thermal contact with the corresponding stack holder 150 above the second heat pipe 162. In this way, the connection positions of the first heat pipe 161, the second heat pipe 162 and the casing 110 are located between the adjacent cell stacks 120, rather than at the bottoms of the cells of the cell stacks 120, so that the connection between the first heat pipe 161 and the casing 110 and the second heat pipe 162 and the thermal contact between the first heat pipe 161 and the cells in the cell stacks 120 do not interfere with each other, and thus the connection between the first heat pipe 161 and the casing 110, the connection between the first heat pipe 161 and the second heat pipe 162, and the thermal contact between the first heat pipe 161 and the cells in the cell stacks 120 are all more reliable. The first heat pipe 161 may be connected to the housing 110 and the second heat pipe 162 at a connection by way of a welded connection or a threaded fastener connection. The manner of the welded connection or the threaded fastener connection hardly affects the heat transfer effect between the first heat pipe 161 and the housing 110 and between the first heat pipe 161 and the second heat pipe 162.

Further preferably, the heat transfer assembly 160 further comprises an insulation member (not shown), which may be made of an insulating material, or may be a vacuum insulation member. A heat insulator is disposed between the first heat pipe 161 and the cell stack 120, the width of the heat insulator (i.e., the dimension in the direction parallel to the width direction of the cell stack 120) is smaller than the width of any one of the first heat pipe 161 and the battery cell, and the width of the heat insulator decreases as the distance from the connection increases. That is, the thermal contact area of the first heat pipe 161 with the battery cells in the cell stack 120 increases as the distance from the connection increases. Specifically, in the present embodiment, the thermal contact area of the first heat pipe 161 with the battery cells in the cell stack 120 is largest at the middle position of the cell stack 120. As such, each cell in the cell stack 120 may be made to have substantially the same thermal resistance at the connection with respect to the first heat pipe 161. No matter which battery cell is higher in temperature, the heat of the higher battery cell can be rapidly transferred to the first heat pipe 161. As described above, a part of the heat may be transferred to the connection point of the other first heat pipe 161 through the first heat pipe 161 corresponding to the battery cell with the higher temperature and the second heat pipe 162 connected to the first heat pipe 161, and may be transferred to the battery cell of the other battery stack 120 from the connection point of the other first heat pipe 161. Since each cell of the stack 120 has substantially the same thermal resistance relative to the junction, each cell of the other stacks 120 absorbs substantially the same amount of heat from the junction, reducing the possibility of thermal runaway due to excessive temperature of the cells in the other stacks 120 that are closer to the junction. In addition, for the entire battery system, no matter which battery cell has a higher temperature, during the heat transfer from the higher temperature battery cell to the battery cells in the other battery stacks 120, particularly, in the initial stage, a plurality of battery cells having the same thermal resistance with respect to a certain connection simultaneously absorb heat from the battery cell having a higher temperature from the connection, compared with the case where no thermal insulation member is provided or a thermal insulation member with the same width is provided (in this case, the thermal resistance of the battery cell close to the connection is relatively small, and the thermal resistance of the battery cell far from the connection is relatively large), it is more favorable for the heat of the battery cell with higher temperature to be rapidly transferred to the battery cell far from the connection in the other battery stacks 120, more battery monomers absorb heat from corresponding connecting positions at the same time, and the temperature of the battery monomer with higher temperature is greatly reduced.

Optionally, the heat transfer assembly 160 further comprises a heat transfer pad (not shown) made of a flexible material. The flexible material is, for example, heat conductive silicone rubber, heat conductive foam rubber, or the like. The thermal delivery pad is disposed between the thermal insulation and the cell stack 120. In the assembled state, the bottoms of the cells of the cell stack 120 may not be flat. In the present embodiment, a heat insulator having a non-uniform width dimension is further provided between the cell stack 120 and the first heat pipe 161. Both of these conditions may adversely affect the thermal contact of the battery cell with the first heat pipe 161. Thermal contact between the cell stack 120 (more specifically, the battery cells) and the first heat pipe 161 may be facilitated by a heat transfer pad made of a flexible material.

Preferably, the size of the heat transfer pad is greater than or equal to the size of the first heat pipe 161 so that each battery cell can make good thermal contact with the first heat pipe 161.

Preferably, a temperature detection device may be provided on the first heat pipe 161 or the second heat pipe 162 to detect a temperature change in the battery cell. The temperature detection device may be connected to a battery management system to output a detection signal through the battery management system.

Optionally, additional thermal insulation (not shown) is disposed between adjacent cells in the stack 120. Similar to the insulation in the heat transfer assembly 160 described above, the additional insulation may be made of an insulating material. The additional insulation may also be vacuum insulation. The additional thermal insulation member may prevent heat transfer between adjacent battery cells by means of direct thermal conduction, particularly in the case where the temperature of one of the battery cells is high. Generally, the heat distribution is unbalanced easily caused by transferring the heat between the adjacent battery cells by direct heat conduction. When a certain battery cell in the battery stack 120 is at a higher temperature and is about to generate thermal runaway or has generated thermal runaway, if direct heat conduction can occur between adjacent battery cells, most of heat of the battery cell at the higher temperature can be transferred to the adjacent battery cell adjacent to the battery cell at the higher temperature through the direct heat conduction, and the heat obtained by other battery cells far away from the battery cell at the higher temperature is less, so that the temperature of the adjacent battery cell is also higher, and the possibility of thermal runaway of the adjacent battery cell is higher.

Optionally, the cell stack 120 further includes a bus bar (not shown) disposed on top of each cell. The bus bar is generally made of a metal material. On the one hand, the bus bars can carry current to realize series connection or parallel connection between the battery cells; on the other hand, because the bus bar is in soaking contact with each single battery, the temperature of each single battery tends to be consistent, and the possibility that thermal runaway occurs due to the fact that the temperature of one single battery is high is greatly reduced.

In a second aspect of the invention, there is also provided a vehicle provided with any one of the battery systems described above. For brevity, further description is omitted here.

The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

While the present invention has been described in connection with the embodiments, it is to be understood by those skilled in the art that the foregoing description and drawings are merely illustrative and not restrictive of the broad invention, and that this invention not be limited to the disclosed embodiments. Various modifications and variations are possible without departing from the spirit of the invention.

Claims

1. A battery system for a vehicle, the battery system comprising:

a housing having an interior cavity;

a cell stack disposed in the internal cavity, the cell stack including a plurality of cells; and

an exhaust flow guide device disposed above the cell stack, the exhaust flow guide device including:

the body is fixedly arranged above the battery stack relative to the shell and is provided with a plurality of holes corresponding to the battery cells; and

a plurality of covers corresponding to the plurality of holes and each covering the corresponding hole on the upper side of the body, wherein the size of the cover is larger than the size of the corresponding hole.

2. The battery system of claim 1, wherein the cover is coupled to the body.

3. The battery system of claim 1 or 2, further comprising a biasing member fixedly disposed relative to the housing and biased against the body.

4. The battery system according to claim 3, wherein the holes and the cover are sized such that, when the cover covers the holes corresponding thereto, both sides of the cover are spaced apart from side edges of the body by a predetermined distance to form pressing portions on the body, the pressing members being pressed against the pressing portions.

5. The battery system of claim 4, further comprising a stack holder disposed at a longitudinal end of the stack and connected to the housing, the press being connected to the stack holder.

6. The battery system of claim 5, wherein the stack holder comprises:

a first support member;

a second support disposed opposite to the first support in a longitudinal direction of the cell stack; and

at least one deformable assembly disposed between the first and second supports, wherein each of the deformable assemblies includes first and second bendable members bendable toward each other.

7. The battery system of claim 5 or 6, further comprising a heat transfer assembly, at least a portion of the heat transfer assembly being disposed between the stack and the housing, the heat transfer assembly being in thermal contact with each of the battery cells and the housing.

8. The battery system of claim 7, wherein the battery system comprises a plurality of cell stacks, and the heat transfer assembly comprises:

a plurality of first heat pipes disposed between the cell stack and the housing and extending along a longitudinal direction of the cell stack, the first heat pipes being in thermal contact with the housing and each of the battery cells of the cell stack; and

at least one second heat pipe disposed between the stack holder and the case and connecting the plurality of first heat pipes, the first heat pipe being connected to the case at a connection of the first heat pipe and the second heat pipe.

9. The battery system of claim 8, wherein the heat transfer assembly further comprises a thermal shield disposed between the first heat pipe and the cell stack, the thermal shield having a width that is less than a width of any of the first heat pipe and the battery cell, and the width of the thermal shield decreases with increasing distance from the connection.

10. A vehicle characterized in that the vehicle includes the battery system according to any one of claims 1 to 9.