Battery pack and vehicle

Abstract

The utility model relates to a battery pack and a vehicle, the battery pack comprises a box body and a cooling system, the cooling system comprises an expansion water tank, a heat exchanger and a cooling waterway arranged in the box body, the input end of the heat exchanger is communicated with the output end of the cooling waterway, and the output end of the heat exchanger is communicated with the input end of the expansion water tank; at least one hot melting valve is arranged on the cooling water way, and the output end of the expansion water tank is further connected with the heat exchanger. The original water path of the battery pack is simply upgraded, the hot melting valve is additionally arranged on the cooling water path in the battery pack, during normal use, the cooling system of the battery pack circularly cools the battery pack, and when the battery pack is subjected to thermal runaway, the hot melting valve in the battery pack is opened due to high-temperature baking; cooling liquid in the expansion water tank can flow through the heat exchanger, enters the cooling water path and enters the battery pack from the hot melting valve to cool the battery pack; and meanwhile, firefighters can quickly inject fire fighting water into the battery pack through the expansion water tank, so that a fire is quickly and effectively extinguished.

Description

Technical Field

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

[0002] As the number of electric vehicles continues to increase, the safety of electric vehicles has attracted more and more attention from consumers, among which the spontaneous combustion of electric vehicle battery packs is particularly noteworthy. The power battery of an electric vehicle is generally arranged directly below the middle of the vehicle chassis to minimize the center of gravity of the vehicle and to protect the battery pack to the maximum extent when the vehicle collides. However, when the power battery of an electric vehicle burns due to thermal runaway, this arrangement brings great inconvenience to the firefighting work. Because the power battery itself is a closed structure and is located at the bottom of the vehicle chassis, it is difficult to spray the fire extinguishing agent and fire water directly into the battery pack, and the fire cannot be extinguished in a timely and effective manner, which may cause greater disasters.

[0003] In order to solve the above problems, although some people have proposed some ideas, due to the complexity of the system, the implementation cost is too high or there are other risks. For example, the patent with application number CN201920614032.9 discloses a power battery fire-fighting device and vehicle, in which a water injection pipe and a drainage pipe are set on the outside of the battery pack. When the temperature of the battery pack is too high, fire-fighting water is injected through the water injection pipe to play a role in extinguishing the fire. However, the device additionally sets a water injection pipe and a drainage pipe on the battery pack, which increases the cost of the battery pack. The additional water injection port and drainage port are likely to affect the waterproof performance of the battery pack; in addition, when the whole vehicle wades or water is added through the water injection pipe by human accident, it will directly cause water to enter the battery pack and damage the battery pack. The patent with application number 202223151823.3 discloses a patent application for a waterway assembly and a vehicle having the same, and proposes a waterway assembly that can be docked with a fire hose, which increases the water injection efficiency, but the waterway assembly also needs to open an additional hole in the battery pack shell, and it cannot avoid the problem of accidental water ingress to the waterway assembly and damage to the battery pack. Utility Model Content

[0004] Based on this, it is necessary to provide a battery pack and a vehicle to address the problem that the current battery pack fire water channel requires additional holes to be opened in the battery pack shell, which can easily affect the waterproof performance of the battery pack and cannot prevent accidental water ingress into the water channel components and damage the battery pack.

[0005] A battery pack proposed in the utility model includes a box body and a cooling system, wherein the cooling system includes an expansion water tank, a heat exchanger and a cooling water circuit arranged inside the electric box body, the input end of the heat exchanger is connected with the output end of the cooling water circuit and its output end is connected with the input end of the expansion water tank; at least one hot melt valve that can be opened at high temperature is arranged on the cooling water circuit, and the output end of the expansion water tank is also connected with the heat exchanger.

[0006] As a further improvement of the above solution of the utility model, the hot melt valve has a hot melt portion. When the temperature is greater than or equal to the melting point of the hot melt portion, the hot melt valve opens; when the temperature is less than the melting point of the hot melt portion, the hot melt valve remains closed. Preferably, the melting point of the hot melt portion is 180°C; preferably, to ensure the normal operation of the battery pack, the hot melt valve needs to remain closed below 150°C.

[0007] As a further improvement of the above-mentioned scheme of the utility model, the cooling water circuit includes a water inlet pipe, a water outlet pipe and multiple cooling plates. The multiple cooling plates are arranged between the water inlet pipe and the water outlet pipe, and a cooling channel is arranged inside the cooling plate. The water inlet end and the water outlet end of the cooling channel are respectively connected to the water inlet pipe and the water outlet pipe; at least one hot melt valve is arranged on the water outlet pipe.

[0008] As a further improvement of the above solution of the utility model, the water outlet pipe is connected to at least one branch pipe, and a hot melt valve is arranged at one end of the branch pipe away from the water outlet pipe.

[0009] As a further improvement of the above solution of the utility model, the water inlet pipe and the water outlet pipe respectively have a water inlet and a water outlet penetrating to the outside of the box body, and the input end of the heat exchanger is connected to the water outlet.

[0010] As a further improvement of the above solution of the utility model, the cooling system also includes a water pump, the input end of the water pump is connected to the output end of the expansion water tank and the output end of the water pump is connected to the water inlet.

[0011] As a further improvement of the above scheme of the utility model, the cooling system also includes a first hose, a second hose, a third hose, a fourth hose and a fifth hose, the two ends of the first hose are respectively connected to the water outlet and the input end of the heat exchanger, the two ends of the second hose are respectively connected to the heat exchanger and the input end of the expansion water tank, the two ends of the third hose are respectively connected to the water pump input end and the heat exchanger, the two ends of the fourth hose are respectively connected to the output end of the expansion water tank and the third hose, and the two ends of the fifth hose are respectively connected to the water pump output end and the water inlet.

[0012] As a further improvement of the above solution of the utility model, the first hose, the second hose, the third hose, the fourth hose and the fifth hose are all fire-resistant metal hoses.

[0013] The utility model also provides a vehicle, which comprises the battery pack as mentioned above.

[0014] As a further improvement of the above solution of the utility model, the vehicle is a pure electric vehicle, a hybrid electric vehicle or a hydrogen fuel vehicle.

[0015] Compared with the prior art, the utility model has the following beneficial effects:

[0016] 1. The utility model simply upgrades the original water circuit of the battery pack and adds a hot melt valve to the cooling water circuit inside the battery pack. During normal use, the cooling system of the battery pack circulates and cools the battery pack. When the battery pack experiences thermal runaway, the hot melt valve inside the battery pack is opened by high temperature baking. The coolant in the expansion water tank can flow through the heat exchanger into the cooling water circuit and enter the battery pack from the hot melt valve to cool the battery pack. At the same time, firefighters can quickly inject fire water into the battery pack through the expansion water tank to quickly and effectively extinguish the fire. The utility model does not make any changes to the original structure of the battery pack, solves the problem that the current battery pack cannot effectively extinguish fires after thermal runaway occurs, does not affect the air tightness and safety of the battery pack due to the addition of too many components, and has a simple structure and is easy to implement.

[0017] 2. The hot melt valve provided inside the battery pack of the utility model will only be opened by high temperature baking when the battery pack is burning, and will not cause unexpected water ingress into the battery pack due to accidental water injection from the outside, so it is safe and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A schematic diagram of the structure of a battery pack proposed in an embodiment of the utility model;

[0019] Figure 2 A schematic diagram of the structure of a cooling water circuit in a battery pack proposed in an embodiment of the utility model;

[0020] Figure 3 A schematic diagram of the structure of a hot melt valve in a battery pack proposed in an embodiment of the utility model.

[0021] Figure numerals: 1. tank; 2. expansion tank; 3. heat exchanger; 4. hot melt valve; 5. water inlet pipe; 6. water outlet pipe; 7. cooling plate; 8. water inlet; 9. water outlet; 10. water pump; 11. first hose; 12. second hose; 13. third hose; 14. fourth hose; 15. fifth hose; 16. branch pipe. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] It should be noted that when a component is referred to as being "mounted on" another component, it may be directly on the other component or there may be a central component. When a component is considered to be "set on" another component, it may be directly set on the other component or there may be a central component at the same time. When a component is considered to be "fixed to" another component, it may be directly fixed on the other component or there may be a central component at the same time.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art in the technical field of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "or / and" used herein includes any and all combinations of one or more related listed items.

[0025] In view of the problem that the current fire-fighting water channel of a battery pack requires additional holes to be opened in the battery pack shell, which easily affects the waterproof performance of the battery pack and cannot prevent accidental water ingress into the water channel components and damage to the battery pack, this embodiment provides a battery pack that simply upgrades the original water channel of the battery pack to solve the problem that the current battery pack cannot effectively extinguish a fire after thermal runaway occurs. The airtightness and safety of the battery pack will not be affected by the addition of too many components, and the structure is simple and easy to implement.

[0026] The battery pack of this embodiment is applied to a vehicle, and the vehicle is provided with a vehicle body. The battery pack of this embodiment is installed on the lower side of the chassis of the vehicle body. The vehicle can be a pure electric vehicle, a hybrid vehicle or a hydrogen fuel vehicle. Figure 1 , Figure 2 The battery pack of this embodiment includes a box body 1, a battery module (not shown) arranged in the box body 1, and a cooling system. The cooling system includes an expansion water tank 2, a heat exchanger 3 and a cooling water circuit, and may also include a water pump 10, a first hose 11, a second hose 12, a third hose 13, a fourth hose 14 and a fifth hose 15.

[0027] The cooling water circuit is arranged inside the box 1, and the cooling water circuit includes a water inlet pipe 5, a water outlet pipe 6 and a plurality of cooling plates 7. The water inlet pipe 5 and the water outlet pipe 6 respectively have a water inlet 8 and a water outlet 9 which are arranged outside the box 1. Figure 3The water outlet pipe 6 is located inside the box body 1 and is connected to a branch pipe 16 near the water outlet 9. A hot melt valve 4 that can be opened at high temperatures is installed at one end of the branch pipe 16 away from the water outlet pipe 6. In this embodiment, the hot melt valve 4 is kept closed below 150°C to ensure the normal operation of the battery pack, and can be opened above 180°C to extinguish the fire when thermal runaway occurs. The hot melt valve 4 can be a plastic plug made of high-temperature resistant material in the prior art or a valve that can be opened at high temperatures through other principles in the prior art. The hot melt valve 4 can be easily obtained in the field of fire protection and will not be described in detail here. A plurality of cooling plates 7 are arranged between the water inlet pipe 5 and the water outlet pipe 6. A cooling channel is arranged inside the cooling plate 7. The water inlet end and the water outlet end of the cooling channel are respectively connected to the water inlet pipe 5 and the water outlet pipe 6.

[0028] The expansion water tank 2 is an important component in the battery pack cooling system, which accommodates the expansion of the system water in the cooling system. A water injection port is provided on the top of the expansion water tank 2 and a sealing cover is connected to the water injection port. The sealing cover is opened to inject coolant into the expansion water tank 2. An output end is provided at the bottom of the expansion water tank 2 and an input end is provided on its side. The output end of the expansion water tank 2 is connected to the fourth hose 14. In this embodiment, the expansion water tank 2 is made of steel plate and can be a circular or rectangular structure.

[0029] The heat exchanger 3 is an important component in the battery pack cooling system, which is used to cool the coolant after heat exchange with the battery module. It adopts the existing technology and will not be described in detail here. In this embodiment, the input end of the heat exchanger 3 is connected to the water outlet 9 through the first hose 11, and the output end of the heat exchanger 3 is connected to the input end of the expansion water tank 2 through the second hose 12.

[0030] The water pump 10 is also an important component in the battery pack cooling system, which provides power to transport the coolant in the expansion tank 2 to the cooling water circuit inside the box body 1. The input end of the water pump 10 is connected to the heat exchanger 3 through the third hose 13, and the third hose 13 is also connected to the fourth hose 14. The output end of the water pump 10 is connected to the water inlet 8 through the fifth hose 15.

[0031] When this embodiment is used, Figure 1As shown in the direction of the solid arrow, when the battery is dissipating heat normally, under the action of the water pump 10, the coolant flows from the expansion water tank 2 through the fourth hose 14 and the fifth hose 15 into the water inlet pipe 5, and then flows into each cooling plate 7 to remove the heat generated by the battery pack through the cooling plate 7. At this time, the coolant temperature rises and the coolant flows from the outlet pipe 6 and the first hose 11 to the heat exchanger 3. The coolant is cooled in the heat exchanger 3. The cooled coolant is divided into two paths: one path flows to the water pump 10 through the third hose 13 to form a circulating cooling water path for the battery pack; the other path flows back to the expansion water tank 2 through the second hose 12 to form a second loop; these two loops work together to allow the battery cooling system to circulate normally. When the battery pack is thermally runaway and burns, the water flow direction of the battery pack cooling water path is Figure 1 In the direction of the dotted arrow, due to the battery pack failure, the water pump 10 no longer works, and the hot melt valve 4 inside the battery pack is opened by high temperature baking. The coolant in the expansion water tank 2 can flow through the fourth hose 14, the third hose 13, the heat exchanger 3, the first hose 11, the water outlet pipe 6, the hot melt valve 4 and then enter the battery pack to cool down the modules and cells inside the battery pack. At the same time, using the aforementioned waterway, firefighters can quickly inject fire water into the battery pack through the expansion water tank 2 to quickly extinguish the fire.

[0032] This embodiment simply upgrades the original water circuit of the existing battery pack and adds a hot melt valve 4 to the cooling water circuit inside the battery pack. During normal use, the cooling system of the battery pack circulates and cools the battery pack. When the battery pack is thermally runaway, the hot melt valve 4 inside the battery pack is opened by high temperature baking, and the coolant in the expansion water tank 2 can flow through the heat exchanger 3 into the cooling water circuit and enter the battery pack from the hot melt valve 4 to cool the battery pack. The hot melt valve 4 set inside the battery pack will only be opened by high temperature baking when the battery pack burns, and will not cause unexpected water inflow into the battery pack due to accidental external water injection, which is safe and reliable.

[0033] It should be noted that, in this embodiment, the first hose 11, the second hose 12, the third hose 13, the fourth hose 14 and the fifth hose 15 are all metal hoses with fire-resistant properties. Such fire-resistant hoses have been widely used in the fire protection field and will not be described in detail here.

[0034] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0035] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A battery pack, comprising a box (1) and a cooling system, wherein the cooling system comprises an expansion water tank (2), a heat exchanger (3) and a cooling water circuit arranged inside the box (1), wherein the input end of the heat exchanger (3) is connected to the output end of the cooling water circuit and the output end thereof is connected to the input end of the expansion water tank (2); characterized in that: At least one hot melt valve (4) capable of opening at high temperature is arranged on the cooling water circuit, and the output end of the expansion water tank (2) is also connected to the heat exchanger (3).

2. The battery pack according to claim 1, characterized in that: The hot melt valve (4) has a hot melt portion. When the temperature is greater than or equal to the melting point of the hot melt portion, the hot melt valve (4) opens; when the temperature is less than the melting point of the hot melt portion, the hot melt valve (4) remains sealed.

3. The battery pack according to claim 1, characterized in that: The cooling water circuit comprises a water inlet pipe (5), a water outlet pipe (6) and a plurality of cooling plates (7); the plurality of cooling plates (7) are arranged between the water inlet pipe (5) and the water outlet pipe (6); a cooling channel is arranged inside the cooling plate (7); a water inlet end and a water outlet end of the cooling channel are respectively connected to the water inlet pipe (5) and the water outlet pipe (6); and at least one hot melt valve (4) is arranged on the water outlet pipe (6).

4. The battery pack according to claim 3, characterized in that: The water outlet pipe (6) is connected to at least one branch pipe (16), and a hot melt valve (4) is provided at one end of the branch pipe (16) away from the water outlet pipe (6).

5. The battery pack according to claim 3, characterized in that: The water inlet pipe (5) and the water outlet pipe (6) respectively have a water inlet (8) and a water outlet (9) which are penetrated to the outside of the box body (1), and the input end of the heat exchanger (3) is connected to the water outlet (9).

6. The battery pack according to claim 5, characterized in that: The cooling system further comprises a water pump (10), the input end of the water pump (10) being in communication with the output end of the expansion water tank (2) and the output end of the water pump (10) being in communication with the water inlet (8).

7. The battery pack according to claim 6, characterized in that: The cooling system further comprises a first hose (11), a second hose (12), a third hose (13), a fourth hose (14) and a fifth hose (15); the two ends of the first hose (11) are respectively connected to the water outlet (9) and the input end of the heat exchanger (3); the two ends of the second hose (12) are respectively connected to the heat exchanger (3) and the input end of the expansion water tank (2); the two ends of the third hose (13) are respectively connected to the input end of the water pump (10) and the heat exchanger (3); the two ends of the fourth hose (14) are respectively connected to the output end of the expansion water tank (2) and the third hose (13); and the two ends of the fifth hose (15) are respectively connected to the output end of the water pump (10) and the water inlet (8).

8. The battery pack according to claim 7, characterized in that: The first hose (11), the second hose (12), the third hose (13), the fourth hose (14) and the fifth hose (15) are all fire-resistant metal hoses.

9. A vehicle, characterized in that: It comprises a battery pack as claimed in any one of claims 1 to 8.

10. The vehicle according to claim 9, characterized in that The vehicle is a pure electric vehicle, a hybrid vehicle or a hydrogen fuel vehicle.

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