A new cooling structure with two cooling plates for power batteries

Abstract

The present invention belongs to the technical field of thermal management of power batteries, and specifically, is a novel cooling structure with two layers of cooling plates applied to power batteries, comprising a single cooling plate and a second cooling plate, wherein the single cooling plate comprises an upper plate and a lower plate, the upper plate and the lower plate are integrated by high-temperature brazing, the second cooling plate is also composed of an upper plate and a lower plate, the single cooling plate and the second cooling plate are connected by a second liquid inlet pipe and a second liquid outlet pipe, a total liquid inlet pipe and a total liquid outlet pipe are installed on the single cooling plate; a flow channel is arranged on the lower plate, the flow channel is obtained by a stamping process, and the coolant in the flow channel flows through the bottom of each battery cell; battery cell modules are respectively placed on the single cooling plate and the second cooling plate; the present invention can reduce the development cost of the thermal management system, reduce the occupied space in the battery pack, and improve the thermal management performance.

Description

Technical Field

[0001] The present invention belongs to the technical field of thermal management of power batteries, and in particular is a novel cooling structure with two layers of cooling plates applied to power batteries. Background Art

[0002] With the rapid development of the domestic new energy industry and the crazy internal competition in the new energy vehicle market, most OEMs have to speed up the research and development progress to cope with various market demands. High mileage has always been the focus of clients.

[0003] The close coordination between the various parts of the car and the good use of space create a comfortable and reliable means of transportation. However, increasing the range will increase the overall space layout of the power battery. As a result, there will be a superposition of batteries in the height space, and at this time, the test of the thermal management system becomes particularly important.

[0004] Obviously, the design of thermal management structure will be relatively complicated due to the space stacking of batteries. So, how to break through the conventional structural design and maximize the space utilization in a limited space during the design process will face huge challenges.

[0005] The cooling plate solutions commonly used in the industry currently also have a two-layer cooling plate design, but they occupy a large space, have relatively low thermal management performance, and are costly. Therefore, compared with these traditional cooling plate solutions, the present invention has good thermal management performance, occupies less space, and has a lower development cost. Summary of the invention

[0006] In order to make up for the deficiencies of the prior art, reduce the development cost of the thermal management system, reduce the occupied space in the battery pack, and improve the thermal management performance, the present invention proposes a new cooling structure with a two-layer cooling plate applied to a power battery.

[0007] The technical solution adopted by the present invention to solve its technical problem is: the present invention is a new type of cooling structure with two cooling plates applied to a power battery, comprising a cooling plate and a cooling plate, wherein the cooling plate comprises an upper plate and a lower plate, the upper plate and the lower plate are integrated by high-temperature brazing, the cooling plate also consists of an upper plate and a lower plate, the cooling plate and the cooling plate are connected through a second liquid inlet pipe and a second liquid outlet pipe, a total liquid inlet pipe and a total liquid outlet pipe are installed on the cooling plate, a total liquid inlet end is installed on the total liquid inlet pipe, a total liquid outlet end is installed on the total liquid outlet pipe, and the total liquid inlet end and the total liquid outlet end are connected to a vehicle water pump through a pipeline; when the cooling structure is working, the internal coolant will flow through the total liquid inlet end, the total liquid inlet pipe, the cooling plate, the second liquid inlet pipe, the second cooling plate, the second liquid outlet pipe, the cooling plate, the total liquid outlet pipe and the total liquid outlet end in sequence;

[0008] The lower plate is provided with a flow channel, which is obtained by a stamping process. The direction of the flow channel is specially designed according to the distribution of the battery cells, and the coolant in the flow channel flows through the bottom of each battery cell;

[0009] The first cooling plate and the second cooling plate are respectively provided with battery core modules, and thermal conductive adhesive is installed between the first cooling plate, the second cooling plate and the modules. The first cooling plate and the second cooling plate are different in size, area and internal flow channel.

[0010] Preferably, the edge of the lower plate in the two-layer cooling plate is bent, and the area of ​​the lower plate in the two-layer cooling plate is larger than the area of ​​the upper plate.

[0011] Preferably, the first layer of cooling plate is provided with interface 1 and interface 2, and both interface 1 and interface 2 on the first layer of cooling plate are located on the upper plate, there are three groups of interface 1 on the first layer of cooling plate, and there is one group of interface 2 on the first layer of cooling plate, the total liquid inlet pipe, the total liquid outlet pipe, and the second layer liquid outlet pipe are connected to the first layer of cooling plate through interface 1, and the second layer liquid inlet pipe is connected to the first layer of cooling plate through interface 2;

[0012] Interface 1 and interface 3 are installed on the second layer cooling plate. The second layer liquid outlet pipe is connected to the second layer cooling plate through interface 3. The second layer liquid inlet pipe is connected to the second layer cooling plate through interface 1. Interface 1 and interface 3 on the second layer cooling plate are both located on the lower plate.

[0013] Preferably, the upper plate is provided with a pressing groove, the pressing groove is located on the surface of the upper plate facing the lower plate, the surface of the upper plate facing the module is kept flat, and the pressing groove corresponds to the flow channel.

[0014] Preferably, the pressing groove includes a forward groove and a transverse groove, the forward groove corresponds to the flow channel, the transverse groove connects two adjacent flow channels, and the forward groove and the transverse groove do not contact each other;

[0015] A heat pipe is installed in the pressing groove by brazing.

[0016] Preferably, the heat pipes are provided in a plurality of groups, and the heat pipes are staggered in the length direction;

[0017] The width of the forward groove is greater than the width of the transverse groove, and the width of the heat pipe is equal to the width of the transverse groove.

[0018] Preferably, a protection hole is opened on the upper plate, and the protection hole is blocked by brazing;

[0019] The brazing temperature at the protection hole is lower than the brazing temperature between the upper plate and the lower plate;

[0020] The protection hole is connected to the flow channel, and the coolant in the cooling structure contains fire-retardant components.

[0021] Preferably, the protection hole is located in the forward groove, and the heat pipe in the forward groove blocks the protection hole.

[0022] The beneficial effects of the present invention are as follows:

[0023] 1. The present invention discloses a novel cooling structure with two cooling plates for power batteries. A first cooling plate and a second cooling plate are provided. After the first cooling plate and the second cooling plate are connected to each other, cooling water circulates between the first cooling plate and the second cooling plate. This makes the structure of the thermal management system and the cooling water circulation relatively simple, which can reduce the development cost of the thermal management system and reduce the space occupied by thermal management components in the battery pack. At the same time, it improves the thermal management performance and increases the service life of the battery pack.

[0024] 2. The present invention describes a novel cooling structure with a two-layer cooling plate for a power battery. By setting an interface on the lower plate of the two-layer cooling plate, the pipeline forming process is simplified, bending tooling is reduced, and the same pipeline is shared, the types of materials are reduced, and the forming process of thermal management components can be simplified to facilitate processing and production.

[0025] 3. The present invention describes a new cooling structure with a two-layer cooling plate for a power battery. By arranging transverse grooves, longitudinal grooves, heat pipes and protection holes, the heat between the cooling water in different flow channels and positions in the cooling plate is conducted and balanced, so that the surface temperature of the cooling plate is uniform, thereby avoiding temperature differences between different battery cell modules, affecting the service life of the battery cell and causing safety hazards. In addition, when thermal runaway occurs in the battery cell, the protection hole is opened to release the fire-retardant coolant to delay or prevent the thermal runaway of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention will be further described below in conjunction with the accompanying drawings.

[0027] Figure 1 It is a schematic diagram of the structure of the heat pipe system of the battery pack composed of the cooling structure of the present invention;

[0028] Figure 2 It is a schematic diagram of the locations of the parts of the cooling structure in the heat pipe system of the battery pack in the present invention;

[0029] Figure 3 It is a front view of a cooling plate in the present invention;

[0030] Figure 4 It is a front view of an upper plate in a layer of cooling plates in the present invention;

[0031] Figure 5It is a front view of the lower plate in a cooling plate of the present invention;

[0032] Figure 6 It is a front view of interface 1 and interface 2 on a cooling plate of the present invention;

[0033] Figure 7 It is a front view of the two-layer cooling plate in the present invention;

[0034] Figure 8 It is a front view of the upper plate in the two-layer cooling plate of the present invention;

[0035] Fig. 9 It is a front view of the lower plate in the two-layer cooling plate of the present invention;

[0036] Fig.10 It is a front view of the interface 3 in the two-layer cooling plate of the present invention;

[0037] Fig.11 It is a schematic diagram of the structure of the upper plate in the present invention;

[0038] Fig.12 yes Figure 7 A partial enlarged picture of the upward perspective at point A in the middle;

[0039] Fig.13 yes Fig.11 A partial enlarged view of point B in the middle.

[0040] In the figure: a first layer cooling plate 1, a second layer cooling plate 11, an upper plate 12, a lower plate 13, a total liquid inlet pipe 2, a total liquid outlet pipe 21, a second layer liquid inlet pipe 22, a second layer liquid outlet pipe 23, an interface 1 24, an interface 2 25, an interface 3 26, a total liquid inlet end 27, a total liquid outlet end 28, a battery cell module 3, a thermal conductive adhesive 31, a pressed groove 4, a forward groove 41, a transverse groove 42, a heat pipe 5, and a protective hole 6. DETAILED DESCRIPTION

[0041] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0042] like Figures 1 to 13As shown, the present invention discloses a novel cooling structure with two cooling plates 11 for a power battery, comprising a first cooling plate 1 and a second cooling plate 11, wherein the first cooling plate 1 comprises an upper plate 12 and a lower plate 13, wherein the upper plate 12 and the lower plate 13 are integrated by high temperature brazing, and the second cooling plate 11 also comprises an upper plate 12 and a lower plate 13, wherein the first cooling plate 1 and the second cooling plate 11 are connected by a second liquid inlet pipe 22 and a second liquid outlet pipe 23, wherein the first cooling plate 1 A total liquid inlet pipe 2 and a total liquid outlet pipe 21 are installed on the top, a total liquid inlet end 27 is installed on the total liquid inlet pipe 2, a total liquid outlet end 28 is installed on the total liquid outlet pipe 21, and the total liquid inlet end 27 and the total liquid outlet end 28 are connected to the vehicle water pump through a pipeline; when the cooling structure is working, the internal coolant will flow through the total liquid inlet end 27, the total liquid inlet pipe 2, a first cooling plate 1, a second liquid inlet pipe 22, a second cooling plate 11, a second liquid outlet pipe 23, a first cooling plate 1, the total liquid outlet pipe 21 and the total liquid outlet end 28 in sequence;

[0043] The lower plate 13 is provided with a flow channel, which is obtained by stamping and forming. The direction of the flow channel is specially designed according to the distribution of the battery cells, and the coolant in the flow channel flows through the bottom of each battery cell;

[0044] The first cooling plate 1 and the second cooling plate 11 are respectively provided with a battery module 3, and a heat conductive adhesive 31 is installed between the first cooling plate 1, the second cooling plate 11 and the module. The first cooling plate 1 and the second cooling plate 11 are different in size, area and internal flow channel;

[0045] During operation, the liquid outlet of the vehicle water pump is connected to the total liquid inlet end 27, and the coolant is introduced so that the coolant passes through the flow channel of the first cooling plate 1. At this time, the coolant has a temperature, and the heat or cold is transferred to the battery module 3 on the first cooling plate 1 through the thermal conductive adhesive 31 through the good thermal conductivity of the cooling plate. At this time, the temperature in the coolant has already been heat exchanged, and then, the coolant in the first cooling plate 1 enters the second cooling plate 11 through the second liquid inlet pipe 22, and transfers the heat or cold to the battery module 3 on the second cooling plate 11 through the thermal conductive adhesive 31. After that, after the coolant completes the circulation inside the second cooling plate 11, the coolant flows back to the first cooling plate 1 through the second liquid outlet pipe 23 again, and heat is exchanged with the remaining battery module 3 on the first cooling plate 1 again. Finally, the coolant flows out to the liquid inlet of the vehicle water pump through the total liquid outlet end 28, completing a cycle;

[0046] At the same time, through the mutual connection between the first cooling plate 1 and the second cooling plate 11, the circulation process of the coolant can be good and simple, the development cost of the heat management system can be reduced, and the space occupied by the components of the heat management system in the power battery pack can be reduced. At the same time, through the relatively simple circulation process of the coolant, the load of the vehicle water pump is reduced, the good cooling effect of the battery module 3 is ensured, the heat management performance is improved, and the service life of the battery pack is increased;

[0047] At the same time, the cooling plate composed of the upper plate 12 and the lower plate 13 integrated by brazing can have efficient heat transfer performance. In addition, according to the distribution of battery cells inside the power battery pack, the flow channel on the lower plate 13 is specially designed, so that the coolant passing through the flow channel can flow through the bottom of each battery cell, and take away the heat or cold of the battery cell in the form of heat exchange, so that the temperature between the battery cells inside the power battery can be relatively uniform, the temperature uniformity is improved, and the temperature difference and temperature rise between different battery cells are avoided, which affects the safety and service life of the battery cells. At the same time, through the special flow channel design, the temperature of the battery cell is managed, so that the charging and discharging of the battery is under comfortable working conditions, thereby extending the service life of the battery pack.

[0048] As an embodiment of the present invention, the edge of the lower plate 13 in the two-layer cooling plate 11 is bent, and the area of ​​the lower plate 13 in the two-layer cooling plate 11 is larger than the area of ​​the upper plate 12;

[0049] Since the second-layer cooling plate 11 needs to support the battery cell module 3 above it, the second-layer cooling plate 11 is subjected to a greater force than the first-layer cooling plate 1. Therefore, the edge of the lower plate 13 in the second-layer cooling is bent to improve the strength of the second-layer cooling plate 11, so that the second-layer cooling plate 11 is not prone to deformation, bending, etc. during use, thereby avoiding affecting the normal use of the second-layer cooling plate 11 and the sufficient fixation of the battery cell module 3 on the second-layer cooling plate 11, thereby affecting the safe use of the battery cell.

[0050] As an embodiment of the present invention, the first layer of cooling plate 1 is installed with interface 1 24 and interface 2 25, the interface 1 24 and interface 2 25 on the first layer of cooling plate 1 are both located on the upper plate 12, there are three groups of interface 1 24 on the first layer of cooling plate 1, and there is one group of interface 25 on the first layer of cooling plate 1, the total liquid inlet pipe 2, the total liquid outlet pipe 21, and the second layer liquid outlet pipe 23 are connected to the first layer of cooling plate 1 through interface 1 24, and the second layer liquid inlet pipe 22 is connected to the first layer of cooling plate 1 through interface 2 25;

[0051] The second layer cooling plate 11 is provided with an interface 1 24 and an interface 3 26, the second layer liquid outlet pipe 23 is connected to the second layer cooling plate 11 through the interface 3 26, the second layer liquid inlet pipe 22 is connected to the second layer cooling plate 11 through the interface 1 24, and the interface 1 24 and the interface 3 26 on the second layer cooling plate 11 are both located on the lower layer plate 13;

[0052] By making an opening on the lower plate 13 of the second cooling plate 11 and installing interface 1 24 and interface 3 26, it is avoided that the interface is installed on the upper plate 12 of the second cooling plate 11 to occupy the space in the battery pack. At the same time, since interface 1 24 and interface 3 26 on the second cooling plate 11 are located on the lower plate 13, the interface direction on the second cooling plate 11 is directly toward the first cooling plate 1. Therefore, during production, the second liquid inlet pipe 22 and the second liquid outlet pipe 23 can share a common model to reduce the types of materials. At the same time, when connecting the first cooling plate 1 and the second cooling plate 11, the forming of the second liquid inlet pipe 22 and the second liquid outlet pipe 23 is relatively simple, and no additional bending processing is required, avoiding unnecessary bends in the pipeline, increasing the flow resistance when the coolant flows, thereby reducing the workload of the vehicle water pump, so that the coolant inlet temperature at the total liquid inlet end 27 can maintain temperature consistency, better heat and cool the battery cell module 3, and improve the thermal management performance.

[0053] As an embodiment of the present invention, the upper plate 12 is provided with a pressing groove 4, the pressing groove 4 is located on the surface of the upper plate 12 facing the lower plate 13, the surface of the upper plate 12 facing the module is kept flat, and the pressing groove 4 corresponds to the flow channel;

[0054] A groove 4 is pressed out on the surface of the upper plate 12 by stamping, and the groove 4 corresponds to the flow channel on the lower plate 13, so that when the coolant flows through the flow channel, the coolant will also contact the groove 4, so that the groove 4 produces a fin effect, thereby increasing the heat exchange area and heat exchange efficiency between the coolant and the upper plate 12, and making the temperature of the surface of the upper plate 12 as uniform as possible, that is, the temperature of the surface of the cooling plate is uniform. At the same time, the upper plate 12 exchanges heat with the battery module 3 through the thermal conductive adhesive 31. When the contact area between the upper plate 12 and the coolant is increased and the heat exchange effect is improved, the heat exchange capacity and heat exchange effect of the battery module 3 are improved, and the heat accumulated on the battery module 3 is conducted away, so that the temperature between each battery module 3 is relatively uniform, and the temperature difference and temperature rise between the battery module 3 are avoided to be too large, which affects the normal operation and service life of the battery module 3.

[0055] As an embodiment of the present invention, the pressure groove 4 includes a forward groove 41 and a transverse groove 42, the forward groove 41 corresponds to the flow channel, the transverse groove 42 connects two adjacent flow channels, and the forward groove 41 and the transverse groove 42 do not contact each other;

[0056] A heat pipe 5 is installed in the pressure groove 4 by brazing;

[0057] Since the area of ​​the cooling plate is relatively large, the length of the flow channel will be relatively long. With the heat exchange between the coolant and the battery module 3, the temperature of the coolant in the cooling plate far away from the flow channel entrance will be relatively high, which will cause uneven temperature on the surface of the cooling plate, and then the temperature between the battery modules 3 that are heat-pipe-controlled by the cooling plate will also be uneven, resulting in that the heat generated during the operation of the battery module 3 cannot be effectively dissipated, thereby affecting the safety and service life of the power battery. Therefore, a forward groove 41 and a transverse groove 42 are provided, and heat pipes 5 are installed in both: the forward groove 41 and the heat pipe 5 therein are distributed along the direction of the flow channel, so as to conduct and balance the heat in the length direction of the flow channel, reduce the temperature difference between the coolant near the flow channel entrance and the coolant far away from the flow channel entrance in the cooling plate, and ensure that the temperature of the coolant at different positions in the same flow channel is the same as much as possible;

[0058] The transverse grooves 42 and the heat pipes 5 therein are distributed along the direction perpendicular to the flow channel, so as to conduct and balance the heat in adjacent or mutually parallel flow channels, reduce the temperature difference between the coolants in different flow channels, and ensure that the temperature of the coolants in different flow channels is the same as much as possible;

[0059] Therefore, by conducting and evenly distributing heat through the transverse grooves 42 and the heat pipes 5 in the forward grooves 41, the temperatures of the coolants in different parts of the cooling plate can be made as similar as possible, and the surface temperature of the cooling plate can be evenly distributed, ensuring that the temperatures of the various battery modules 3 are uniform and the heat is dissipated in time, thereby avoiding the cooling plate area being too large, resulting in temperature differences between the coolants at different positions inside it, and then resulting in temperature differences between the battery modules 3 at corresponding positions, affecting the service life of the battery cells and creating safety hazards.

[0060] As an embodiment of the present invention, the heat pipes 5 are provided in a plurality of groups, and the heat pipes 5 are staggered in the length direction;

[0061] The width of the forward groove 41 is greater than the width of the transverse groove 42 , and the width of the heat pipe 5 is equal to the width of the transverse groove 42 ;

[0062] When the length of the heat pipe 5 is relatively long, the heat pipe 5 has a large heat conduction resistance, which affects the use effect of the heat pipe 5. Therefore, multiple groups of heat pipes 5 are provided, and the heat pipes 5 are staggered in the length direction, so that the length of each heat pipe 5 is relatively short, ensuring that the heat pipe 5 has a good heat conduction effect, facilitating heat conduction and balance between coolants in various places in the cooling plate, and ensuring uniform temperature on the surface of the cooling plate;

[0063] At the same time, since the transverse groove 42 will penetrate and cross two or more adjacent flow channels, in order to prevent the coolant from flowing directly through the transverse groove 42 and affecting the flow path and flow direction of the coolant, the width of the transverse groove 42 and the heat pipe 5 are made the same, so that after the heat pipe 5 is installed in the transverse groove 42 and fixed by brazing, the part of the transverse groove 42 located between the two flow channels is blocked and closed, so as to prevent the coolant from flowing and transferring directly through the transverse groove 42, affecting the normal flow of the coolant and causing a dead angle for the flow of the coolant;

[0064] At the same time, since the forward grooves 41 are distributed along the direction of the flow channel, and multiple groups of forward grooves 41 can also produce the effect of fins, the width of the forward grooves 41 is greater than the width of the transverse grooves 42, that is, after the heat pipe 5 is installed in the forward grooves 41, there is still a gap between the heat pipe 5 and the forward grooves 41, and the coolant can also flow in the gap between the two, thereby ensuring that the heat exchange area between the upper plate and the coolant is increased, and the heat exchange between the coolant and the heat pipe 5 can also be guaranteed, thereby fully ensuring the temperature uniformity of the cooling plate surface and the heat dissipation effect.

[0065] As an embodiment of the present invention, a protection hole 6 is opened on the upper plate 12, and the protection hole 6 is blocked by brazing;

[0066] The brazing temperature at the protection hole 6 is lower than the brazing temperature between the upper plate 12 and the lower plate 13;

[0067] The protection hole 6 is connected to the flow channel, and the coolant in the cooling structure contains fire-retardant components;

[0068] By opening the protection hole 6 on the upper plate 12 and sealing it by brazing, the cooling plate can be used normally. At the same time, when thermal runaway of the battery cell occurs in the battery pack, the high temperature generated by the thermal runaway will cause the brazing on the protection hole 6 to melt, thereby interconnecting the protection hole 6 with the flow channel in the cooling plate, releasing the coolant containing the fire-retardant component, and using the fire-retardant coolant to delay or prevent the thermal runaway of the battery cell in the battery pack, thereby improving the safety of the use of the power battery;

[0069] At the same time, since the upper plate 12 and the lower plate 13 constituting the cooling plate are also connected by brazing, in order to ensure that the cooling plate can maintain a complete and normal structure when thermal runaway of the battery cell occurs in the battery pack, the brazing material protection hole 6 and the cooling plate with different melting temperatures are used for brazing connection, thereby ensuring that the upper plate 12 and the lower plate 13 will not separate from each other when the battery cell thermal runaways, thereby ensuring the smooth flow channel in the cooling plate, so as to smoothly release the fire-retardant coolant to the thermal runaway battery cell, delay or prevent the thermal runaway of the battery cell, and improve the safety of the use of the power battery.

[0070] As an embodiment of the present invention, the protection hole 6 is located in the forward groove 41, and the heat pipe 5 in the forward groove 41 blocks the protection hole 6;

[0071] The protection hole 6 is arranged in the forward groove 41, so that the heat pipe 5 in the forward groove 41 will block the protection hole 6 after being placed, and then when the heat pipe 5 is fixed in the forward groove 41 by brazing, the protection hole 6 will be blocked together. At the same time, since the heat pipe 5 blocks the protection hole 6, it will be convenient to put the solder during brazing and avoid excessive solder from flowing out of the protection hole 6 after melting, resulting in a bulge on the other side of the protection hole 6, affecting the installation of the battery module 3;

[0072] At the same time, by shielding the protection hole 6 through the heat pipe 5, the connection between the heat pipe 5 and the forward groove 41 will also have the effect of sealing the protection hole 6, thereby increasing the area of ​​the protection hole 6 closed by brazing, improving the sealing effect of the protection hole 6, and avoiding incomplete sealing of the protection hole 6, resulting in coolant leakage when the cooling plate is used, affecting the normal use and safety of the power battery.

[0073] The specific workflow is as follows:

[0074] During operation, the liquid outlet of the vehicle water pump is connected to the total liquid inlet end 27, and the coolant is introduced so that the coolant passes through the flow channel of the first cooling plate 1. At this time, the coolant has a temperature, and the heat or cold is transferred to the battery module 3 on the first cooling plate 1 through the thermal conductive adhesive 31 through the good thermal conductivity of the cooling plate. At this time, the temperature in the coolant has already been heat exchanged, and then, the coolant in the first cooling plate 1 enters the second cooling plate 11 through the second liquid inlet pipe 22, and transfers the heat or cold to the battery module 3 on the second cooling plate 11 through the thermal conductive adhesive 31. After that, after the coolant completes the circulation inside the second cooling plate 11, the coolant flows back to the first cooling plate 1 through the second liquid outlet pipe 23 again, and heat is exchanged with the remaining battery module 3 on the first cooling plate 1 again. Finally, the coolant flows out to the liquid inlet of the vehicle water pump through the total liquid outlet end 28, completing a cycle;

[0075] At the same time, by interconnecting the first cooling plate 1 and the second cooling plate 11, the circulation process of the coolant can be good and simple, reducing the development cost of the heat management system and reducing the space occupied by the components of the heat management system in the power battery pack;

[0076] At the same time, according to the distribution of cells inside the power battery pack, the flow channel on the lower plate 13 is specially designed so that the coolant passing through the flow channel can flow through the bottom of each cell, so that the temperature between the cells inside the power battery is relatively uniform;

[0077] The edge of the lower plate 13 in the second cooling layer is bent to improve the strength of the second cooling plate 11;

[0078] By opening the lower plate 13 of the second-layer cooling plate 11 and installing the interface 1 24 and the interface 3 26, the space in the battery pack is avoided. At the same time, during production, the second-layer liquid inlet pipe 22 and the second-layer liquid outlet pipe 23 can share one model, reducing the types of materials. At the same time, the molding of the second-layer liquid inlet pipe 22 and the second-layer liquid outlet pipe 23 is relatively simple, and no additional bending processing is required, avoiding unnecessary bends in the pipeline and increasing the flow resistance when the coolant flows;

[0079] A groove 4 is pressed out on the surface of the upper plate 12 by stamping, and the groove 4 corresponds to the flow channel on the lower plate 13, so that when the coolant flows through the flow channel, the coolant will also contact the groove 4, so that the groove 4 produces a fin effect, so that the temperature of the surface of the upper plate 12 is uniform, that is, the temperature of the surface of the cooling plate is uniform;

[0080] A forward groove 41 and a transverse groove 42 are provided, and heat pipes 5 are installed in both of them: the forward groove 41 and the heat pipes 5 therein are distributed along the direction of the flow channel, so as to conduct and balance the heat in the length direction of the flow channel, reduce the temperature difference between the coolant near the flow channel entrance and the coolant far from the flow channel entrance in the cooling plate, and ensure that the temperature of the coolant at different positions in the same flow channel is the same as much as possible;

[0081] The transverse grooves 42 and the heat pipes 5 therein are distributed along the direction perpendicular to the flow channel, so as to conduct and balance the heat in adjacent or mutually parallel flow channels, reduce the temperature difference between the coolants in different flow channels, and ensure that the temperature of the coolants in different flow channels is the same as much as possible;

[0082] A plurality of groups of heat pipes 5 are arranged, and the heat pipes 5 are staggered in the length direction, so that the length of each heat pipe 5 is relatively short;

[0083] At the same time, the width of the transverse groove 42 and the heat pipe 5 are made the same, so that after the heat pipe 5 is installed in the transverse groove 42 and fixed by brazing, the part of the transverse groove 42 between the two flow channels is blocked and sealed to prevent the coolant from flowing and transferring directly through the transverse groove 42;

[0084] At the same time, the width of the forward groove 41 is made greater than the width of the transverse groove 42, that is, after the heat pipe 5 is installed in the forward groove 41, there is still a gap between the heat pipe 5 and the forward groove 41, and the coolant can also flow in the gap between the two, so that the heat exchange between the coolant and the heat pipe 5 can be ensured while the heat exchange area between the upper plate and the coolant is increased;

[0085] When thermal runaway of the battery cell occurs in the battery pack, the high temperature generated by the thermal runaway will cause the brazing on the protection hole 6 to melt, thereby interconnecting the protection hole 6 with the flow channel in the cooling plate, releasing the coolant containing the fire-retardant component, and using the fire-retardant coolant to delay or prevent the thermal runaway of the battery cell in the battery pack;

[0086] The protection hole 6 is arranged in the forward groove 41, so that the heat pipe 5 in the forward groove 41 will block the protection hole 6 after being placed, and then when the heat pipe 5 is fixed in the forward groove 41 by brazing, the protection hole 6 will be blocked together;

[0087] At the same time, the heat pipe 5 shields the protection hole 6 , so that the connection between the heat pipe 5 and the forward groove 41 can also produce the effect of sealing the protection hole 6 .

[0088] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A novel cooling structure with two cooling plates (11) applied to a power battery, characterized in that: The invention comprises a first cooling plate (1) and a second cooling plate (11), wherein the first cooling plate (1) comprises an upper plate (12) and a lower plate (13), wherein the upper plate (12) and the lower plate (13) are integrated by high-temperature brazing, and the second cooling plate (11) is also composed of an upper plate (12) and a lower plate (13), wherein the first cooling plate (1) and the second cooling plate (11) are connected via a second liquid inlet pipe (22) and a second liquid outlet pipe (23), and a total liquid inlet pipe (2) and a total liquid outlet pipe (21) are installed on the first cooling plate (1); The lower plate (13) is provided with a flow channel, the flow channel is obtained by a stamping process, and the coolant in the flow channel flows through the bottom of each battery cell; The first cooling plate (1) and the second cooling plate (11) are respectively provided with a battery core module (3); the first cooling plate (1) and the second cooling plate (11) are different in size, area and internal flow channel; The upper plate (12) is provided with a pressing groove (4), the pressing groove (4) is located on the surface of the upper plate (12) facing the lower plate (13), the surface of the upper plate (12) facing the module is kept flat, and the pressing groove (4) and the flow channel correspond to each other; The compression groove (4) comprises a forward groove (41) and a transverse groove (42), wherein the forward groove (41) corresponds to the flow channel, the transverse groove (42) connects two adjacent flow channels, and the forward groove (41) and the transverse groove (42) do not contact each other; A heat pipe (5) is installed in the pressure groove (4) by brazing; The heat pipes (5) are provided in a plurality of groups, and the heat pipes (5) are staggeredly distributed in the length direction; The width of the forward groove (41) is greater than the width of the transverse groove (42), and the width of the heat pipe (5) is equal to the width of the transverse groove (42); The upper plate (12) is provided with a protection hole (6), and the protection hole (6) is sealed by brazing; The brazing temperature at the protection hole (6) is lower than the brazing temperature between the upper plate (12) and the lower plate (13); The protection hole (6) is connected to the flow channel, and the coolant in the cooling structure contains fire-retardant components; The protection hole (6) is located in the forward groove (41), and the heat pipe (5) in the forward groove (41) blocks the protection hole (6).

2. A novel cooling structure with two cooling plates (11) applied to a power battery according to claim 1, characterized in that: The edge of the lower plate (13) in the two-layer cooling plate (11) is bent, and the area of ​​the lower plate (13) in the two-layer cooling plate (11) is larger than the area of ​​the upper plate (12).

3. A novel cooling structure with two cooling plates (11) applied to a power battery according to claim 1, characterized in that: The first layer of cooling plate (1) is provided with interface 1 (24) and interface 2 (25); the interface 1 (24) and interface 2 (25) on the first layer of cooling plate (1) are both located on the upper layer plate (12); the total liquid inlet pipe (2), the total liquid outlet pipe (21), and the second layer liquid outlet pipe (23) are connected to the first layer of cooling plate (1) via interface 1 (24); and the second layer liquid inlet pipe (22) is connected to the first layer of cooling plate (1) via interface 2 (25); The second layer cooling plate (11) is provided with interface one (24) and interface three (26); the second layer liquid outlet pipe (23) is connected to the second layer cooling plate (11) via interface three (26); the second layer liquid inlet pipe (22) is connected to the second layer cooling plate (11) via interface one (24); interface one (24) and interface three (26) on the second layer cooling plate (11) are both located on the lower layer plate (13).

Images