Battery pack cooling structure and battery pack

Abstract

The utility model provides a battery pack cooling structure and a battery pack, the battery pack cooling structure is used for cooling the battery pack, the cooling structure comprises: a cold plate main body, the cold plate main body is arranged at the bottom of the battery pack; the heat transfer assembly is fixedly kept on the cold plate main body so as to form heat transfer between the heat transfer assembly and the cold plate main body; a containing cavity is formed between the heat transfer assembly and the cold plate body, and the inner wall of the containing cavity abuts against the battery cell to form heat transfer between the heat transfer assembly and the battery cell. According to the battery pack cooling structure, the heat transfer area of the cold plate is expanded through the heat transfer assembly, so that the cooling effect is improved, and the use quality of the battery pack is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of battery packs, and in particular to a battery pack cooling structure. The utility model also relates to a battery pack equipped with the battery pack cooling structure. Background Art

[0002] In modern electric vehicles, the battery pack undoubtedly plays a vital role. As the "heart" of the car, it provides a continuous source of power to ensure the stable operation of the car. However, the performance and stability of the battery pack are not only related to the power output of the car, but also directly related to the safety and reliability of the vehicle.

[0003] When the battery pack is in a high-load operation state for a long time, a large amount of heat will inevitably be generated inside the battery cell. If this heat is not removed in a timely and effective manner, it will have a serious impact on the quality of the battery pack. Excessive temperature will not only cause the battery performance to decline, affecting the driving range and charging efficiency, but it may also accelerate battery aging and shorten the battery life. More seriously, excessive temperature may also cause thermal runaway of the battery, which in turn may cause safety accidents such as fire, posing a threat to the life safety of the occupants.

[0004] Therefore, a cooling structure is provided inside the battery pack to cool the battery cells. The existing cooling structure is generally a cold plate provided inside the battery pack. The cold plate takes away the heat generated by the battery cells through the circulation of liquid or gas, thereby reducing the temperature of the battery pack. However, the existing cold plate often only cools one side of the battery pack, and the cooling effect is not ideal.

[0005] Specifically, the existing cold plate design can often only cool one side of the battery pack. The heat generated by the battery cell during operation is dissipated in all directions and at multiple angles, but the cold plate can only exchange heat on one side. This one-way cooling method obviously cannot fully meet the heat dissipation requirements of the battery cell, so it is difficult to achieve an ideal cooling effect, which is not conducive to improving the quality of the battery pack. Utility Model Content

[0006] In view of this, the utility model aims to provide a battery pack cooling structure, so as to improve the use quality of the battery pack by optimizing the cooling structure.

[0007] In order to achieve the above object, the technical solution of the utility model is implemented as follows:

[0008] A battery pack cooling structure is used for cooling the battery pack, and the cooling structure comprises:

[0009] A cold plate body, the cold plate body being arranged at the bottom of the battery pack;

[0010] A heat transfer component, wherein the heat transfer component is fixedly held on the cold plate body to form heat transfer between the heat transfer component and the cold plate body;

[0011] An accommodating cavity is formed between the heat transfer component and the cold plate body, and an inner wall of the accommodating cavity abuts against the battery core to form heat transfer between the heat transfer component and the battery core.

[0012] Furthermore, the heat transfer component includes a heat transfer body having a flow channel, and a pressure relief valve disposed on the heat transfer body;

[0013] The flow channel is in one-way communication with the whole vehicle water system.

[0014] Furthermore, the heat transfer body includes a top plate, and fins extending from the top plate toward the cold plate body;

[0015] The fins divide the accommodating cavity into a plurality of chambers, and the inner wall of each chamber abuts against the battery core.

[0016] Furthermore, the heat transfer body is made of metal material.

[0017] Furthermore, a check valve connected to the flow channel is provided on the top plate, and a liquid inlet end of the check valve is connected to the vehicle water system.

[0018] Furthermore, the heat transfer body is provided with a three-way pipe connected with the flow channel;

[0019] The pressure relief valve and the check valve are respectively arranged at two free ends of the three-way pipe, and the pressure relief valve is located above the check valve.

[0020] Furthermore, a liquid level sensor is provided on the three-way pipe, and the liquid level sensor is used to detect the liquid level of the three-way pipe.

[0021] Furthermore, it also includes a heat-conducting layer, which is fixedly maintained on the contact surface between the heat transfer component and the cold plate body.

[0022] Furthermore, the heat-conducting layer is a heat-conducting structural adhesive.

[0023] Compared with the prior art, the utility model has the following advantages:

[0024] The battery pack cooling structure described in the utility model realizes heat transfer between the side surface of the battery cell and the cold plate body through the arrangement of the heat transfer component, so that the heat exchange area between the cold plate body and the battery cell is increased, which is beneficial to the heat extraction of the battery cell, effectively improving the cooling effect and improving the use quality of the battery pack.

[0025] The flow channel in the heat transfer body and the arrangement of the pressure relief valve can, on the one hand, help improve the heat transfer effect of the heat transfer component; on the other hand, when thermal runaway occurs in the battery cell, the heat of the battery cell is transferred to the water in the flow channel, so that the water temperature rises and turns into water vapor and is discharged through the pressure relief valve, which helps reduce the loss caused by thermal runaway of the battery cell. The structure is simple and easy to design and implement.

[0026] The setting of the fins further increases the heat transfer area between the heat transfer body and the battery cell, thereby improving the cooling effect of the cold plate body. The setting of the fins divides the battery cell into multiple chambers, which is beneficial to preventing heat spread after thermal runaway of the battery cell and improving the safety of the battery pack.

[0027] The heat transfer body is made of metal material, which is beneficial to improving the heat transfer efficiency of the heat transfer body and can improve the structural strength of the heat transfer body itself, thereby protecting the battery cells arranged in the accommodating cavity and facilitating design implementation.

[0028] The one-way connection between the heat transfer body and the vehicle water system is achieved through the check valve, which can prevent the liquid in the heat transfer body from flowing back into the vehicle water system. The structure is simple and is conducive to design implementation.

[0029] The arrangement of the three-way pipe allows the pressure relief valve and the check valve to share a common installation base on the heat transfer body, and the pressure relief valve is arranged above the check valve to facilitate exhaust and pressure relief, and the three-way pipe can be arranged below the check valve to store some water as a transition between pressure relief and water replenishment, so as to avoid dry burning after water in the flow channel evaporates, which is conducive to design implementation.

[0030] By setting the liquid level sensor, the liquid level in the three-way pipe can be detected, so as to control the liquid replenishment of the flow channel of the whole vehicle water system.

[0031] The provision of the heat-conducting layer facilitates heat transfer between the heat transfer component and the cold plate body and can avoid collision between the heat transfer component and the cold plate body, thereby helping to ensure safe use of the cold plate body and the heat transfer component and facilitating design implementation.

[0032] The heat transfer component can be bonded to the cold plate body by the heat conductive structural adhesive, which is easy to install and can ensure heat transfer between the heat transfer component and the cold plate body, which is beneficial to design implementation.

[0033] The utility model further provides a battery pack, in which the battery pack cooling structure as described above is installed.

[0034] The battery pack described in the present invention has the same beneficial effects as the battery pack cooling structure described above compared to the prior art, so they will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation on the present invention. In the accompanying drawings:

[0036] Figure 1 This is a schematic diagram of the structure of the battery pack cooling structure according to an embodiment of the utility model;

[0037] Figure 2 A schematic diagram of the structure of the battery pack cooling structure assembled with battery cells according to an embodiment of the utility model;

[0038] Figure 3 A schematic diagram of the internal structure of the battery pack cooling structure according to an embodiment of the utility model;

[0039] Figure 4 for Figure 3 A magnified image of point A;

[0040] Description of reference numerals:

[0041] 1. Cold plate body;

[0042] 101. Liquid inlet; 102. Liquid outlet;

[0043] 2. Heat transfer components;

[0044] 201, heat transfer subject;

[0045] 2011, flow channel; 2012, top plate; 2013, fins;

[0046] 202, pressure relief valve; 203, check valve;

[0047] 204, tee pipe;

[0048] 2041, first end; 2042, second end; 2043, third end;

[0049] 205, liquid level sensor;

[0050] 3. Battery cells;

[0051] s, containing cavity; t, chamber. DETAILED DESCRIPTION

[0052] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0053] In the description of the present invention, it should be noted that if there are terms such as "upper", "lower", "inner", "outer" and the like indicating orientation or positional relationship, they are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, if there are terms such as "first" and "second", they are also used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0054] Taking the battery pack where the battery pack cooling structure described in the utility model is located as an example, the directional words such as "up, down, left, right, front, and back" used in the embodiments are defined based on the up and down direction (also known as the height direction, or the Z direction of the whole pack), the left and right direction (also known as the width direction, or the Y direction of the whole pack), and the front and back direction (also known as the length direction, or the X direction of the whole pack) of the battery pack. "Inside and outside" are defined based on the contour of the corresponding parts. For example, "inside" and "outside" are defined based on the contour of the battery pack, and the side of the battery pack contour close to the middle of the battery pack is "inside", and the opposite is "outside".

[0055] In addition, in the description of the present invention, unless otherwise clearly defined, the terms "installation", "connection", "connection" and "connector" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood in combination with specific circumstances.

[0056] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0057] Embodiment 1

[0058] The present embodiment relates to a battery pack cooling structure, in order to improve the use quality of the battery pack by optimizing the cooling structure.

[0059] In terms of overall structure, combined Figure 1 and Figure 2 As shown, the battery pack cooling structure in this embodiment is used for cooling the battery pack, and the cooling structure includes: a cold plate body 1, which is arranged at the bottom of the battery pack. A heat transfer component 2, which is fixed on the cold plate body to form heat transfer between the heat transfer component 2 and the cold plate body 1. A receiving cavity s is formed between the heat transfer component 2 and the cold plate body 1, and the inner wall of the receiving cavity s abuts against the battery cell 3 to form heat transfer between the heat transfer component 2 and the battery cell 3.

[0060] As configured above, the battery pack cooling structure in this embodiment forms heat transfer between the side of the battery cell 3 and the cold plate body 1 through the setting of the heat transfer component 2, so that the heat exchange area between the cold plate body 1 and the battery cell 3 is increased, which is beneficial to the heat extraction of the battery cell 3, and effectively improves the cooling effect to improve the use quality of the battery pack.

[0061] The cold plate body 1 in this embodiment is arranged at the bottom of the battery pack, Figure 1 As shown, the cold plate body 1 has a liquid inlet 101 and a liquid outlet 102. The liquid inlet 101 inputs low-temperature coolant, and the liquid outlet 102 outputs the circulated coolant. The internal structure of the cold plate body 1 can refer to the cold plate in the prior art.

[0062] In order to improve the safety of battery pack, Figures 1 to 4 As shown, the heat transfer component 2 in this embodiment includes a heat transfer body 201 having a flow channel 2011, and a pressure relief valve 202 arranged on the heat transfer body 201. The flow channel 2011 is unidirectionally connected to the vehicle water system. The flow channel 2011 in the heat transfer body 201 and the pressure relief valve 202 are arranged. On the one hand, the heat transfer effect of the heat transfer component 2 is improved. On the other hand, when the battery cell 3 has thermal runaway, the heat of the battery cell 3 is transferred to the water in the flow channel 2011, so that the water temperature rises and turns into water vapor and is discharged through the pressure relief valve 202, which is beneficial to reduce the loss caused by the thermal runaway of the battery cell 3. The structure is simple and easy to design and implement.

[0063] Specifically, the heat transfer body 201 in this embodiment has a hollow plate body, and the flow channel 2011 is the inner cavity of the hollow plate body, so that the water storage capacity in the heat transfer body 201 can be increased, and it is convenient for water to be discharged through the pressure relief valve 202 when evaporating. The vehicle water system and the flow channel 2011 are unidirectionally connected, so that the water in the flow channel 2011 will not enter the vehicle water system when evaporating, thereby avoiding the evaporation of water in the flow channel 2011 affecting the use of the vehicle water system.

[0064] In order to increase the heat transfer area of ​​the heat transfer body 201, the Figures 1 to 4 As shown, the heat transfer body 201 in this embodiment includes a top plate 2012, and fins 2013 extending from the top plate 2012 to the cold plate body 1. The fins 2013 divide the accommodating cavity s into a plurality of chambers t, and the inner wall of each chamber t abuts against the battery cell 3. The arrangement of the fins 2013 further increases the heat transfer area between the heat transfer body 201 and the battery cell 3, thereby improving the cooling effect of the cold plate body 1. The arrangement of the fins 2013 divides the battery cell 3 into a plurality of chambers t, which is beneficial to preventing the heat spread after the thermal runaway of the battery cell 3, and is beneficial to improving the safety of the battery pack.

[0065] Specifically, the top plate 2012 and the fins 2013 in this embodiment both have hollow plates, and the inner cavities of the top plate 2012 and the fins 2013 are connected to facilitate water storage. The chamber t between two adjacent fins 2013 is used to accommodate the battery cell 3. Preferably, when the spacing between two adjacent fins 2013 meets the thickness of the battery cell 3, the side surfaces of each battery cell 3 in the battery pack can be abutted against the side walls of the fins 2013 to form heat transfer between the side walls of the battery cell 3 and the fins 2013, which is conducive to increasing the heat transfer area between the battery cell 3 and the heat transfer body 201.

[0066] In more detail, the top plate 2012, two adjacent fins 2013 arranged below the top plate 2012 and the cold plate body 1 together form a chamber t, and the inner walls of the chamber t are all in contact with the battery cells 3. Such an arrangement can conduct heat to multiple surfaces of the battery cells 3, and better conduct the heat generated during the use of the battery cells 3 to the cold plate body 1, and take away the heat through the circulation of the coolant in the cold plate body 1, thereby reducing the operating temperature of the battery cells 3.

[0067] In order to further improve the heat transfer efficiency of the heat transfer body 201, the heat transfer body 201 in this embodiment is made of metal material, for example, it can be made of aluminum alloy plate or stainless steel plate in the prior art. The heat transfer body 201 is made of metal material, which is conducive to improving the heat transfer efficiency of the heat transfer body 201, and can improve the structural strength of the heat transfer body 201 itself, and can protect the battery cell 3 arranged in the accommodating cavity s, which is conducive to design implementation.

[0068] In order to better realize the one-way flow of flow channel 2011, combined with Figures 2 to 4 As shown, a check valve 203 connected to the flow channel 2011 is provided on the top plate 2012 of the heat transfer body 201 in this embodiment, and the liquid inlet end of the check valve 203 is connected to the water system of the whole vehicle. The one-way connection between the heat transfer body 201 and the water system of the whole vehicle is achieved through the check valve 203, which can prevent the liquid in the heat transfer body 201 from flowing back into the water system of the whole vehicle, and the structure is simple, which is conducive to design and implementation.

[0069] In order to better exhaust pressure relief, combined Figure 3 and Figure 4As shown, the heat transfer body 201 in this embodiment is provided with a three-way pipe 204 connected with the flow channel 2011, and the pressure relief valve 202 and the check valve 203 are respectively arranged at the two free ends of the three-way pipe 204, and the pressure relief valve 202 is located above the check valve 203 in the height direction of the battery pack. Through the arrangement of the three-way pipe 204, the pressure relief valve 202 and the check valve 203 share a common installation base on the heat transfer body 201, and the pressure relief valve 202 is arranged above the check valve 203 to facilitate exhaust and pressure relief, and the three-way pipe 204 can be arranged below the check valve 203 to store some water as a transition between pressure relief and water replenishment, so as to avoid the situation of dry burning after the water in the flow channel 2011 evaporates, which is conducive to design implementation.

[0070] Specifically, combined with Figure 4 As shown, the three-way pipe 204 is arranged to protrude from the top of the top plate 2012, the first end 2041 of the three-way pipe 204 is connected to the inner cavity of the top plate 2012, the second end 2042 and the third end 2043 of the three-way pipe 204 are the two free ends of the three-way pipe 204, the second end 2042 of the three-way pipe 204 is connected to the check valve 203, and the third end 2043 of the three-way pipe 204 is connected to the pressure relief valve 202. In this way, a certain amount of water can be stored between the second end 2042 of the three-way pipe 204 and the top plate 2012. When the water in the heat transfer body 201 evaporates at high temperature due to thermal runaway of the battery cell 3, the water in the three-way pipe 204 flows into the top plate 2012 under the action of gravity, and flows into each fin 2013 through the top plate 2012, which can avoid the heat transfer body 201 from drying out before the vehicle water system replenishes water into the heat transfer body 201.

[0071] In order to better detect the liquid level in the flow channel 2011, combined with Figure 4 As shown, a liquid level sensor 205 is provided on the three-way pipe 204 in this embodiment. The liquid level sensor 205 is used to detect the liquid level in the three-way pipe 204. The liquid level sensor 205 is electrically connected to the BMS (Battery Management System). Through the setting of the liquid level sensor 205, the liquid level height in the three-way pipe 204 can be detected, and the liquid level monitoring information can be transmitted to the BMS, so as to control the whole vehicle water system to replenish the flow channel 2011.

[0072] Specifically, the liquid level sensor 205 is arranged below the check valve 203. When the liquid level sensor 205 detects that the liquid level drops, the liquid level monitoring information can be transmitted to the BMS, and the liquid level monitoring information is transmitted to the vehicle ECU (Electronic Control Unit) through the BMS. The vehicle ECU controls the vehicle water system to replenish the heat transfer body 201 with liquid.

[0073] In order to facilitate heat transfer between the heat transfer component 2 and the cold plate body 1, the battery pack cooling structure in this embodiment also includes a heat conductive layer, which is fixedly maintained on the contact surface between the heat transfer component 2 and the cold plate body 1. The provision of the heat conductive layer facilitates heat transfer between the heat transfer component 2 and the cold plate body 1 and can avoid collision between the heat transfer component 2 and the cold plate body 1, thereby helping to ensure the safe use of the cold plate body 1 and the heat transfer component 2 and facilitating design implementation.

[0074] In order to facilitate the fixation of the heat transfer component 2 on the cold plate body 1, the heat conductive layer in this embodiment is a heat conductive structural adhesive. The heat transfer component 2 can be bonded to the cold plate body 1 through the heat conductive structural adhesive, which is easy to install and can ensure heat transfer between the heat transfer component 2 and the cold plate body 1, which is beneficial to design implementation.

[0075] When the battery pack cooling structure of this embodiment is in use, firstly, a thermal conductive structural adhesive is applied to the surface of the bottom of the heat transfer body 201 that contacts the cold plate body 1, and the heat transfer body 201 is bonded to the cold plate body 1 through the thermal conductive structural adhesive. Then, the check valve 203 is connected to the vehicle water system, and liquid is injected into the heat transfer body 201. When the liquid level sensor 205 detects that the liquid level is at a preset position, the injection is stopped.

[0076] Under normal use, the heat generated by the battery cell 3 is transferred to the cold plate through the heat transfer body 201, which can ensure the normal operating temperature of the battery cell 3. When the battery cell 3 has thermal runaway, there is water in the fins 2013 on both sides of the thermal runaway battery cell 3. The temperature of the thermal runaway battery cell 3 causes the water temperature in the fins 2013 to rise. As the water temperature rises, the evaporated water vapor causes the pressure relief valve 202 to exhaust and relieve pressure. As the water in the fins 2013 decreases, the temperature generated by the thermal runaway of the battery cell 3 is taken away. The water in the top plate 2012 flows to the fins 2013, causing the liquid level to drop. At this time, the liquid level sensor detects the drop in the liquid level, and the vehicle water system injects water into the heat transfer body 201 through the check valve 203, thereby forming a cooling cycle to continuously cool the thermal runaway battery cell 3 and avoid the heat spread of the thermal runaway of the battery cell 3.

[0077] The battery pack cooling structure in this embodiment can increase the heat transfer area between the cold plate body 1 and the battery cell 3 by setting the heat transfer component 2, thereby improving the cooling efficiency of the cooling structure. It can also absorb the high temperature of the battery cell 3 during thermal runaway by setting the fins 2013 of the heat transfer component 2, thereby preventing the thermal runaway of the battery cell 3 from spreading to other normal battery cells 3, thereby improving the safety of the battery pack. The setting of the battery pack cooling structure in this embodiment improves the cooling efficiency and safety of the battery pack, thereby improving the quality of the battery pack.

[0078] Embodiment 2

[0079] This embodiment relates to a battery pack, in which the battery pack cooling structure of the first embodiment is installed.

[0080] The battery pack of this embodiment, through the arrangement of the battery pack cooling structure in the first embodiment, can increase the heat transfer area between the cold plate body 1 and the battery cell 3, improve the cooling efficiency of the cold plate body 1, and facilitate the discharge of heat from the battery cell 3 in the battery pack. It can also prevent the thermal runaway of the battery cell 3 from spreading through the evaporation of water in the flow channel of the heat transfer component 2, which is beneficial to the safety of the battery pack and helps to improve the quality of the battery pack.

[0081] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A battery pack cooling structure for cooling a battery pack, characterized in that: The cooling structure includes: A cold plate body, the cold plate body being arranged at the bottom of the battery pack; A heat transfer component, wherein the heat transfer component is fixedly held on the cold plate body to form heat transfer between the heat transfer component and the cold plate body; An accommodating cavity is formed between the heat transfer component and the cold plate body, and an inner wall of the accommodating cavity abuts against the battery core to form heat transfer between the heat transfer component and the battery core.

2. The battery pack cooling structure according to claim 1, characterized in that: The heat transfer component includes a heat transfer body having a flow channel, and a pressure relief valve disposed on the heat transfer body; The flow channel is in one-way communication with the whole vehicle water system.

3. The battery pack cooling structure according to claim 2, characterized in that: The heat transfer body includes a top plate, and fins extending from the top plate toward the cold plate body; The fins divide the accommodating cavity into a plurality of chambers, and the inner wall of each chamber abuts against the battery core.

4. The battery pack cooling structure according to claim 3, characterized in that: The heat transfer body is made of metal material.

5. The battery pack cooling structure according to claim 3, characterized in that: A check valve connected to the flow channel is provided on the top plate, and a liquid inlet end of the check valve is connected to the vehicle water system.

6. The battery pack cooling structure according to claim 5, characterized in that: The heat transfer body is provided with a three-way pipe connected with the flow channel; The pressure relief valve and the check valve are respectively arranged at two free ends of the three-way pipe, and the pressure relief valve is located above the check valve.

7. The battery pack cooling structure according to claim 6, characterized in that: The three-way pipe is provided with a liquid level sensor, and the liquid level sensor is used to detect the liquid level of the three-way pipe.

8. The battery pack cooling structure according to any one of claims 1 to 7, characterized in that: It also includes a heat-conducting layer, which is fixedly retained on the contact surface between the heat transfer component and the cold plate body.

9. The battery pack cooling structure according to claim 8, characterized in that: The heat-conducting layer is a heat-conducting structural adhesive.

10. A battery pack, characterized in that: The battery pack is equipped with a battery pack cooling structure as described in any one of claims 1 to 9.

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