A direct cooling plate and an energy storage battery pack

Abstract

The present invention relates to the technical field of liquid cooling heat dissipation, and discloses a direct cooling plate, which includes a first substrate. A flow channel structure is symmetrically arranged along the central axis of the width direction of the first substrate. The first substrate includes an inlet for refrigerant inflow and an outlet for refrigerant discharge. The two flow channel structures share one inlet and one outlet, and the inlet and the outlet are located on the same side and both are located at the middle position in the width direction of the first substrate. The connection between the flow channel structure and the inlet is close to the central axis of the width direction of the first substrate. The flow direction of the refrigerant through the flow channel structure is from the central axis of the width direction of the first substrate to the side close to the width direction of the first substrate. The present invention can improve the heat dissipation efficiency of the battery cells located in the middle of the box body, ensure the consistency of the temperature distribution among multiple battery cells in the box body, that is, ensure good temperature uniformity of the battery pack, improve the service life of the battery pack, and improve the use safety.

Description

Technical Field

[0001] The present invention relates to the technical field of liquid cooling heat dissipation, and particularly relates to a direct cooling plate and an energy storage battery pack. Background Art

[0002] When the battery pack is in use, a large amount of heat is generated by multiple rows and columns of battery cells inside the battery pack box (abbreviated as the box). In order to dissipate heat from the battery cells, a liquid cooling plate made of a metal material is provided below the battery cells in the box. Currently, the liquid cooling plate is internally provided with a wavy flow channel for the coolant to pass through. The two ends of the wavy flow channel are respectively an inlet and an outlet for the coolant to flow through, and the inlet and the outlet are located at the same side ends of the liquid cooling plate.

[0003] When the battery pack is in use, multiple battery cells located in the middle of the box are surrounded by other battery cells, resulting in the temperature of the multiple battery cells located in the middle of the box being higher than that of the battery cells near the side wall of the box. However, when the current liquid cooling plate cools and dissipates heat from the battery cells in the box, the inlet is located at one end of one side of the liquid cooling plate, that is, the coolant first dissipates heat from the battery cells near one side wall of the box, then dissipates heat from the battery cells located in the middle of the box along the wavy flow channel, and then dissipates heat from the battery cells near the other side wall of the box. As a result, the temperature of the coolant flowing through the battery cells located in the middle of the box is higher than that of the coolant near one side wall of the box, resulting in poor heat dissipation effect for the battery cells located in the middle of the box, and also a large temperature difference between the battery cells located in the middle of the box and the battery cells near the side wall of the box, thereby shortening the service life of the battery pack and easily leading to the risk of thermal runaway. Summary of the Invention

[0004] In order to overcome the deficiencies of the prior art, one of the purposes of the present invention is to provide a direct cooling plate, which can improve the heat dissipation efficiency of the battery cells located in the middle of the box, ensure the consistency of the temperature distribution among multiple battery cells in the box, that is, ensure good temperature uniformity of the battery pack, improve the service life of the battery pack, and improve the use safety.

[0005] The technical solution adopted by the present invention is as follows: A direct cooling plate includes a first substrate, and a flow channel structure is symmetrically arranged along the central axis of the width direction of the first substrate. The first substrate includes an inlet for the refrigerant to flow in and an outlet for the refrigerant to flow out. The two flow channel structures share one inlet and one outlet, and the inlet and the outlet are located on the same side and are both located at the middle position in the width direction of the first substrate. The connection between the flow channel structure and the inlet is close to the central axis of the width direction of the first substrate, and the flow direction of the refrigerant through the flow channel structure is from the central axis of the width direction of the first substrate to the side close to the width direction of the first substrate.

[0006] Explanation: The battery pack includes a box and multiple battery modules located inside the box. Each group of battery modules includes multiple battery cells, and the direct cooling plate is located below the battery modules.

[0007] Principle of the technical solution:

[0008] The refrigerant flows into the flow channel structure from the inlet. Since the connection between the flow channel structure and the inlet is close to the central axis in the width direction of the first substrate, the flow direction of the refrigerant through the flow channel structure is from the central axis in the width direction of the first substrate towards the side close to the width direction of the first substrate. The central axis in the width direction of the first substrate corresponds to the battery cell in the middle of the box body. That is, the refrigerant first flows through the battery cell in the middle of the box body and then through the battery cell close to the side wall of the box body. That is, it dissipates heat from the battery cell in the middle of the box body first and then from the battery cell close to the side wall of the box body. Since the two flow channel structures are symmetrically arranged, it is equivalent to artificially dividing the multiple battery cells in the box body into two groups from the central axis in the width direction of the first substrate, and dissipating heat from the corresponding group of battery cells through the flow channel structure respectively.

[0009] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0010] 1) Through the flow channel structure of the present invention, the refrigerant can dissipate heat from the battery cells arranged from the central axis in the width direction of the first substrate towards the side close to the width direction of the first substrate in sequence. That is, it can dissipate heat from the battery cell in the middle of the box body first, that is, it can dissipate heat from the battery cell with a high temperature in the middle of the box body first, which can improve the heat dissipation efficiency of the battery cell in the middle of the box body and prevent thermal runaway of the battery cell in the middle of the battery pack due to untimely heat dissipation. The symmetrically arranged flow channel structure can divide the battery cells inside the box body into two groups with the central axis in the width direction of the first substrate as the boundary line, and simultaneously dissipate heat from the corresponding group of battery cells respectively starting from the middle of the box body, which can quickly dissipate heat from the battery cells in the battery pack and improve the heat dissipation efficiency of the battery pack to ensure the long-term stable operation of the battery pack;

[0011] 2) Since the inlet and the outlet are located on the same side and both are located in the middle position in the width direction of the first substrate, and the connection between the flow channel structure and the inlet is close to the central axis in the width direction of the first substrate, the refrigerant dissipates heat from the battery cells arranged from the central axis in the width direction of the first substrate towards the side close to the width direction of the first substrate through the flow channel structure in sequence, so that the temperature of the refrigerant is the lowest when it passes through the battery cell in the middle of the box body corresponding to the central axis in the width direction of the first substrate, and the temperature of the refrigerant is slightly lower when it passes through the battery cell corresponding to the side close to the first substrate, which can ensure the consistency of the temperature distribution among multiple battery cells in the box body, that is, ensure good temperature uniformity of the battery pack, improve the service life of the battery pack, and improve the use safety.

[0012] As a preferred embodiment of the present invention, the flow channel structure is spiral and winds out inside. The flow channel structure includes multiple flow channels, and adjacent flow channels with opposite flow directions are located below the same group of battery modules.

[0013] Background Introduction: Usually, coolant is used as the cooling medium, and the coolant is usually a mixed solution of ethylene glycol and water. However, the mixed solution of ethylene glycol and water has certain corrosiveness as a coolant. Long-term use will cause severe corrosion to the wavy flow channels. When the liquid cooling plate is corroded comprehensively, the corrosion products are deposited on the side walls of the wavy flow channels in solid form, which easily leads to roughness of the side walls of the wavy flow channels in the liquid cooling plate, reducing the heat transfer efficiency and the heat dissipation efficiency of the battery cells. When the liquid cooling plate is locally corroded, it is easy for the liquid cooling plate to become locally thinner and perforated, resulting in coolant leakage and causing equipment short-circuit, which is likely to trigger a fire.

[0014] Using nitrogen can avoid corrosion of the wavy flow channels. However, the thermal conductivity of nitrogen is relatively low, and its cooling effect is not as good as that of the mixed solution of ethylene glycol and water. Moreover, the nitrogen cooling system can only be used for refrigeration. When used for heating, an electric heater needs to be used to conduct heat exchange with the heat source through a heat exchanger.

[0015] Using refrigerant can avoid corrosion of the wavy flow channels, and the heat exchange efficiency of the refrigerant is also higher than that of the ethylene glycol aqueous solution. Since the chemical properties of the refrigerant are stable, if leakage occurs, a fire can also be avoided. However, also because the heat exchange efficiency of the refrigerant is higher than that of the coolant, when applied in the wavy flow channels, the refrigerant enters the wavy flow channels from the inlet of the wavy flow channels, takes away the heat of the battery cells in the battery pack, and then flows out from the outlet of the wavy flow channels. It is easy for multiple battery cells near the inlet of the wavy flow channels to have more heat taken away than multiple battery cells near the outlet of the wavy flow channels, resulting in a large temperature difference between multiple battery cells near the inlet of the wavy flow channels and multiple battery cells near the outlet of the wavy flow channels, causing uneven temperature among multiple battery cells in the battery pack. The battery cells in a relatively low-temperature environment for a long time may have problems such as electrolyte solidification and active substances not being able to fully participate in the reaction. The battery cells in a relatively high-temperature environment for a long time will accelerate the internal chemical reaction, resulting in a reduction of active substances, thus making the performance of multiple battery cells inconsistent, accelerating the aging process of the battery cells, and shortening the service life of the battery pack. A large temperature difference between multiple battery cells may also cause short-circuit between battery cells or inside the battery cells, further exacerbating the temperature difference and increasing the safety risk.

[0016] Beneficial effects: 1) The heat taken away from the battery cells that are cooled by the refrigerant first is more, and the heat taken away from the battery cells that are cooled by the refrigerant later is less than that of the battery cells that are cooled by the refrigerant first. The temperatures of multiple battery cells are inconsistent. Since the flow channel structure is spiral and winds out inside, the adjacent flow channels with opposite flow directions are located below the same set of battery modules, making the path of the refrigerant also spiral and winding out inside. It can adjust the temperatures of the battery cells that are cooled by the refrigerant first and the battery cells that are cooled by the refrigerant later, ensuring that the temperatures of multiple battery cells are consistent and the temperature uniformity is good. 2) It can be more suitable for the refrigerant, ensuring the consistency of the temperature distribution among multiple battery cells in the battery pack, that is, ensuring good temperature uniformity of the battery pack, improving the service life of the battery pack, and improving the usage safety. 3) After the present invention is applied to the refrigerant, the cost can also be reduced because the coolant replacement period is short. Based on the performance attenuation and impurity accumulation of the coolant, it needs to be replaced every five years. The refrigerant circulates in a closed system, and its chemical composition and physical properties are relatively stable and will not significantly decay over time, so the refrigerant does not need to be replaced. 4) The cooling system using the refrigerant can be directly used for refrigeration or heating without adding heaters and heat exchangers, reducing the cost.

[0017] As a preferred embodiment of the present invention, a plurality of branch flow channels are provided at each position of the flow channel far from the connection with the adjacent flow channel, and the cross-sectional area of the connection of two adjacent flow channels is equal to the cross-sectional area of the branch flow channels.

[0018] Beneficial effects: 1) Since the working pressure of the refrigerant can reach 2-3 MPa, the cross-sectional area of the flow channel for the coolant flow is usually more than one hundred square millimeters, and the bursting pressure is within 5 MPa. If the refrigerant directly flows into the flow channel designed for the coolant flow, it is easy to cause the direct cooling plate of the flow channel designed for the coolant flow to rupture, resulting in refrigerant leakage or explosion. Therefore, when the refrigerant flows into the direct cooling plate, it is required that the corresponding flow channel cross-sectional area is smaller than the corresponding flow channel cross-sectional area when the coolant flows into the direct cooling plate, and the width becomes narrower. However, this also reduces the contact area between the refrigerant and the battery cells when flowing through the battery cells. The design of multiple branch flow channels can ensure sufficient contact with the battery cells to ensure the heat dissipation effect. Moreover, due to the small flow channel cross-sectional area, multiple branch flow channels can also be designed on the direct cooling plate with the same width, improving the heat dissipation efficiency. 2) Moreover, the branch flow channels are far from the connection of the adjacent flow channels, that is, when the refrigerant flows through the adjacent flow channels, it undergoes diversion, aggregation, and then diversion. The refrigerant is distributed and then aggregated multiple times, avoiding the problem of excessive temperature difference between the battery cells caused by uneven distribution of the refrigerant in each branch flow channel after passing through the branch flow channels. 3) When the refrigerant flows into a plurality of branch flow channels respectively from the connection of two adjacent flow channels, since the cross-sectional area of the connection of two adjacent flow channels is equal to the cross-sectional area of the branch flow channels, the flow rate of the refrigerant will be reduced, making the flow rate of the refrigerant in the branch flow channels less than the flow rate of the refrigerant at the connection of two adjacent flow channels. The flow rate of the refrigerant in the branch flow channels slows down, and the residence time increases, fully absorbing heat and improving the heat dissipation efficiency of the battery cells.

[0019] As a preferred embodiment of the present invention, two branch channels are provided at each end of each said channel away from the connection with the adjacent channel.

[0020] Beneficial effects: The design of the two branch channels can ensure sufficient contact with the battery cells while minimizing the number of parallel channels as much as possible. In existing liquid cooling plates, there are many parallel channels. When the refrigerant passes through a liquid cooling plate with a large number of parallel channels, due to excessive flow division, the refrigerant distribution in each channel is uneven, resulting in some channels having no refrigerant passing through, and there will be a dry steaming phenomenon. That is, in the case of insufficient refrigerant flow, the heat generated by the battery cells cannot be effectively removed, resulting in a sharp increase in local temperature, reducing the heat dissipation efficiency and affecting the service life of the battery cells.

[0021] As a preferred embodiment of the present invention, the branch channels are arranged along the length direction or the width direction of the first substrate. The multiple branch channels arranged at intervals along the length direction of the first substrate are arranged at equal intervals, and the multiple branch channels arranged at intervals along the width direction of the first substrate are arranged at equal intervals.

[0022] Beneficial effects: 1) Since multiple battery cells in the box are arranged in rows and columns in the box, that is, along the width direction and the length direction of the box, when the branch channels are arranged along the length direction or the width direction of the first substrate, it can adapt to the distribution of the battery cells and fully dissipate heat for the battery cells; 2) The equal interval arrangement can first ensure the rational layout of the direct cooling plate space and fully arrange multiple channels to evenly dissipate heat for each group of battery modules. Secondly, while dissipating heat for the battery cells, adjacent branch channels can also affect each other, avoiding the formation of local hot spots or cold spots, and further ensuring the consistency of the temperature distribution among multiple battery cells in the box.

[0023] As a preferred embodiment of the present invention, the longitudinal cross-sectional area of the branch channel is 18 - 20 square millimeters.

[0024] Beneficial effects: The cross-sectional area of the existing channel is 100 square millimeters, and the bursting pressure is within 5 MPa, while the working pressure of the refrigerant can reach 2 - 3 MPa. Using the existing channel directly for the refrigerant flow in the direct cooling plate is likely to cause the direct cooling plate to rupture, resulting in refrigerant leakage or explosion. When the longitudinal cross-sectional area of the branch channel is 18 - 20 square millimeters, the bursting pressure of the branch channel can reach more than twenty MPa, which can improve the safety factor and ensure the normal and safe operation of the refrigerant as a cooling medium.

[0025] As a preferred embodiment of the present invention, the channel structure includes a first channel and a second channel located at both ends respectively. The first channel is arranged along the length direction of the first substrate and is close to the central axis of the width direction of the first substrate. The second channel is arranged along the length direction of the first substrate and is located on one side of the first channel. The first channel and the second channel are located below the same group of battery modules.

[0026] Beneficial effects: The design that the first flow channel is arranged along the length direction of the first substrate and close to the central axis of the width direction of the first substrate can dissipate heat from the battery cells in the middle of the battery pack first, preventing thermal runaway of the battery cells in the middle of the battery pack due to untimely heat dissipation.

[0027] As a preferred embodiment of the present invention, the flow channel structure further includes a third flow channel in the shape of a square located on one side of the central axis of the width direction of the first substrate, a fourth flow channel located in the third flow channel, and a fifth flow channel in the shape of a square located in the third flow channel and surrounding the fourth flow channel. The third flow channel is communicated with the first flow channel, and the third flow channel, the fourth flow channel, and the fifth flow channel are sequentially in communication, and the fifth flow channel is communicated with the second flow channel.

[0028] Beneficial effects: The designs that the third flow channel and the fifth flow channel are in the shape of a square, and the fifth flow channel surrounds the fourth flow channel and is located in the third flow channel can ensure that the flow channel structure is spiral and winds out internally, so as to ensure that the refrigerant flows in different directions in two adjacent flow channels, thereby enabling the adjustment of the temperature of the same battery cell, and further making the temperatures of multiple battery cells consistent.

[0029] As a preferred embodiment of the present invention, the fourth flow channel includes a fifth connecting channel and a wavy connecting channel communicated with the fifth connecting channel. The fifth connecting channel is communicated with the fourth connecting channel, and the wavy connecting channel is communicated with the fifth flow channel.

[0030] Beneficial effects: The wavy connecting channel, on the premise of ensuring that the first flow channel structure has a positive rotation (the third flow channel in the shape of a square) and a rotation (the fifth flow channel in the shape of a square), compared with the design of the flow channel continuously rotating inward and then rotating back, the wavy connecting channel can simplify the design, reduce the manufacturing cost, and in the same area, the wavy connecting channel can facilitate the design of as many waves as possible, so as to increase the contact surface with the battery cells and improve the heat dissipation efficiency.

[0031] The second object of the present invention is to provide an energy storage battery pack, which further includes the direct cooling plate described above, and further includes a second substrate. The second substrate is a flat plate, the first substrate and the second substrate are connected by stamping and brazing, and the battery module is attached to the surface of the second substrate.

[0032] Beneficial effects: The second substrate is a flat plate, which can fully fit with the battery module, and then cooperate with the first substrate to effectively dissipate heat from the battery module. Brief Description of the Drawings

[0033] Figure 1 is an exploded view of the direct cooling plate of the present invention;

[0034] Figure 2 is a schematic structural diagram of the first substrate of the present invention;

[0035] Figure 3 is a schematic structural view of the first basic part of the present invention;

[0036] Figure 4 is a schematic structural view of the first substrate of the present invention from another angle;

[0037] Figure 5 is a schematic structural view at position A of the present invention;

[0038] Figure 6 is a schematic structural view of a part of the energy storage battery pack of the present invention;

[0039] Figure 7 is a schematic structural view at position B of the present invention;

[0040] Figure 8 is a schematic structural view of another part of the energy storage battery pack of the present invention from another angle. Detailed embodiments

[0041] Typical embodiments embodying the features and advantages of the present invention will be specifically described in the following description. It should be understood that the present invention can have various variations in different embodiments, all of which do not depart from the scope of the present invention, and the descriptions and illustrations therein are for illustrative purposes in essence and not for limiting the present invention.

[0042] In the description of the present application, the orientation or positional relationship indicated by terms such as "first", "second", "one side", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the structure referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present application.

[0043] The present invention will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0044] Reference numerals include: first substrate 1, second substrate 2, first flow channel 3, second flow channel 4, first confluence 5, second confluence 6, first connecting channel 71, second connecting channel 72, third connecting channel 73, fourth connecting channel 74, fifth connecting channel 81, wavy connecting channel 82, sixth connecting channel 91, seventh connecting channel 92, eighth connecting channel 93, ninth connecting channel 94, branch flow channel 10, battery module 11.

[0045] As Figures 1-6 shown, the direct cooling plate, as Figure 1 shown, includes a first substrate 1 and a second substrate 2 connected to the first substrate 1, as Figure 2As shown in the figure, the first substrate includes an inlet for the refrigerant to flow in and an outlet for the refrigerant to flow out. Along the central axis of the width direction of the first substrate 1, spiral flow channel structures that wind around internally are symmetrically arranged. The two flow channel structures share one inlet and one outlet, and the inlet and the outlet are located on the same side and both are at the middle position in the width direction of the first substrate. The connection between the flow channel structure and the inlet is close to the central axis of the width direction of the first substrate. The flowing direction of the refrigerant through the flow channel structure is from the central axis of the width direction of the first substrate to the side close to the width direction of the first substrate.

[0046] As Figure 3 shown in the figure, the flow channel structure includes a first flow channel 3 and a second flow channel 4 located at both ends respectively, a third flow channel in the shape of a square located on one side of the central axis of the width direction of the first substrate 1, a fourth flow channel located inside the third flow channel, and a fifth flow channel in the shape of a square that surrounds the fourth flow channel and is located inside the third flow channel. The third flow channel is connected to the first flow channel 3, and the third flow channel, the fourth flow channel, and the fifth flow channel are in sequential communication. The fifth flow channel is connected to the second flow channel 4.

[0047] The first flow channel 3 is arranged along the length direction of the first substrate 1 and is close to the central axis of the width direction of the first substrate 1. The third flow channel includes a first connecting channel 71, a second connecting channel 72, and a third connecting channel 73 that are respectively close to the side of the first substrate 1, and a fourth connecting channel 74 that is close to the first flow channel 3. The fourth connecting channel 74 is located between the fifth flow channel and the second flow channel 4. The first flow channel 3 is connected to the first connecting channel 71, and the first connecting channel 71, the second connecting channel 72, the third connecting channel 73, and the fourth connecting channel 74 are in sequential communication. The first flow channel 3 is connected to the first connecting channel 71, and the fourth connecting channel 74 is connected to the fourth flow channel.

[0048] In this embodiment, the first connecting channel 71 and the third connecting channel 73 are close to the side of the width direction of the first substrate 1, and the second connecting channel 72 is close to the side of the length direction of the first substrate 1.

[0049] The fourth flow channel includes a fifth connecting channel 81 and a wavy connecting channel 82 that is connected to the fifth connecting channel 81. The fifth connecting channel 81 is connected to the fourth connecting channel 74, and the wavy connecting channel 82 is connected to the fifth flow channel. In this embodiment, the wavy connecting channel 82 includes one wave.

[0050] The fifth flow channel includes a sixth connecting channel 91, a seventh connecting channel 92, an eighth connecting channel 93, and a ninth connecting channel 94. The sixth connecting channel 91, the seventh connecting channel 92, the eighth connecting channel 93, and the ninth connecting channel 94 are in sequential communication. The sixth connecting channel 91 is connected to the wavy connecting channel 82, and the ninth connecting channel 94 is connected to the second flow channel 4. The second flow channel 4 is arranged along the length direction of the first substrate 1 and is located on one side of the first flow channel 3.

[0051] A plurality of branch channels 10 are provided at positions of the first channel 3, the second channel 4, the third channel, the fourth channel, and the fifth channel away from the connection points. In this embodiment, two branch channels 10 are provided at positions of the first channel 3, the second channel 4, the first connection channel 71, the second connection channel 72, the third connection channel 73, the fourth connection channel 74, the fifth connection channel 81, the wavy connection channel 82, the sixth connection channel 91, the seventh connection channel 92, the eighth connection channel 93, and the ninth connection channel 94 away from the connection points. The longitudinal sectional area of the branch channel 10 is 18-20 square millimeters, and the sectional area at the connection point of two adjacent channels is equal to the sectional area of the branch channel 10.

[0052] In this embodiment, the wavy connection channel 82 has one wave. The branch channels 10 on the first channel 3, the second channel 4, the second connection channel 72, the fourth connection channel 74, the sixth connection channel 91, and the eighth connection channel 93 are arranged at equal intervals along the length direction of the first substrate 1. The branch channels 10 on the first connection channel 71, the third connection channel 73, the fifth connection channel 81, the seventh connection channel 92, and the ninth connection channel 94 are arranged at equal intervals along the width direction of the first substrate 1.

[0053] In this embodiment, as Figure 2 , 8 shown, adjacent channels with opposite flow directions are located below the same set of battery modules.

[0054] As Figures 3-5 shown, the first channels 3 in the two channel structures converge and are connected to form a first convergence point 5 (which is the inlet for refrigerant inflow). The first convergence point 5 is connected to the inlet. The second channels 4 in the two channel structures converge and are connected to form a second convergence point 6 (which is the outlet for refrigerant discharge). The second convergence point 6 is connected to the outlet. In this embodiment, the first convergence point 5 and the second convergence point 6 are located on the same side.

[0055] In this embodiment, when the refrigerant enters the first flow channel 3 through the first confluence 5, the temperature of the refrigerant itself is low. When the refrigerant dissipates heat from the battery cell opposite to the first flow channel 3, more heat is taken away from the battery cell opposite to the first flow channel 3. The refrigerant continues to dissipate heat for other battery cells through the flow channel structure. As the refrigerant flows through various parts of the flow channel structure, while the refrigerant dissipates heat from the battery cells, the temperature of the refrigerant itself is higher than the temperature when the refrigerant initially enters the first confluence 5. That is, more heat is taken away from the battery cell opposite to the first flow channel 3, and the heat taken away from the battery cells opposite to the subsequent flow channel structure through which the refrigerant flows gradually decreases, resulting in inconsistent temperatures of multiple battery cells. Since both flow channel structures are spiral and wind around inside, the first flow channel 3 and the second flow channel 4 are both arranged along the length direction of the first substrate 1, and the second flow channel 4 is located on one side of the first flow channel 3, that is, the first flow channel 3 and the second flow channel 4 are adjacent, and the battery cells opposite to the first flow channel 3 and the second flow channel 4 are the same. The refrigerant that has dissipated heat from multiple battery cells flows into the second flow channel 4. At this time, the temperature of the refrigerant flowing into the second flow channel 4 is higher than the temperature of the refrigerant flowing into the first flow channel 3, and the battery cells opposite to the second flow channel 4 and the first flow channel 3 are the same. The refrigerant flowing into the second flow channel 4 is equivalent to heating the corresponding battery cells, so that the battery cells that dissipated more heat initially are heated again, that is, the temperature of the battery cells is adjusted, and the temperature of the battery cells is increased, thereby ensuring that the temperatures of multiple battery cells opposite to the structure of the first flow channel 3 are all adjusted, so that the temperatures of multiple battery cells are consistent, ensuring good temperature uniformity of multiple battery cells in the battery pack, and also applicable to the refrigerant as the refrigerant, reducing the influence of the battery cells on the service life of the battery pack and improving the use safety.

[0056] Flow direction of the refrigerant in the direct cooling plate:

[0057] As Figure 2 , 3 shown, the refrigerant flows in from the first confluence 5, and then is split and flows into two flow channel structures respectively. The refrigerant sequentially flows through the first flow channel 3, the first connecting channel 71, the second connecting channel 72, the third connecting channel 73, the fourth connecting channel 74, the fifth connecting channel 81, the wavy connecting channel 82, the sixth connecting channel 91, the seventh connecting channel 92, the eighth connecting channel 93, the ninth connecting channel 94, the second flow channel 4, flows to the second confluence 6, and flows out through the second confluence 6.

[0058] Energy storage battery pack, as Figures 6-7 shown, includes multiple groups of battery modules 11, and also includes the above-mentioned direct cooling plate. The second substrate 2 is a flat plate, and the first substrate 1 and the second substrate 2 are connected by stamping and brazing. The battery module 11 is attached to the surface of the second substrate 2.

[0059] The above embodiments are only the preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. Any non-substantive changes and substitutions made by those skilled in the art based on the present invention belong to the scope of protection required by the present invention.

Claims

1. A direct cooling plate, comprising a first substrate, characterized in that: A flow channel structure is symmetrically arranged along the central axis of the width direction of the first substrate. The first substrate includes an inlet for refrigerant inflow and an outlet for refrigerant discharge. The two flow channel structures share one inlet and one outlet, and the inlet and the outlet are located on the same side and both are in the middle position in the width direction of the first substrate. The connection between the flow channel structure and the inlet is close to the central axis of the width direction of the first substrate. The flow channel structure is spiral and winds around inside, and the flowing direction of the refrigerant through the flow channel structure is to flow from the central axis of the width direction of the first substrate to the side close to the width direction of the first substrate and then back to the central axis of the width direction of the first substrate for multiple times; The flow channel structure includes multiple flow channels. The adjacent flow channels with opposite flowing directions are located below the same group of battery modules. The refrigerant path is spiral and winds around inside. The refrigerant passes through the flow channel structure to adjust the temperatures of the battery cells that are cooled by the refrigerant first and the battery cells that are cooled by the refrigerant later, so that the temperatures of multiple battery cells are the same; Each flow channel is provided with multiple branch flow channels away from the connection with the adjacent flow channel. The cross-sectional area at the connection of two adjacent flow channels is equal to the cross-sectional area of the branch flow channels. When the refrigerant flows through the adjacent flow channels, it undergoes flow splitting, aggregation, and then flow splitting again. The refrigerant passes through the flow channel structure and is distributed and then aggregated multiple times; The flow channel structure includes a first flow channel and a second flow channel located at both ends respectively. The first flow channel is arranged along the length direction of the first substrate and is close to the central axis of the width direction of the first substrate. The second flow channel is arranged along the length direction of the first substrate and is located on one side of the first flow channel. The first flow channel and the second flow channel are located below the same group of battery modules; The flow channel structure further includes a third flow channel in the shape of a rectangle located on one side of the central axis of the width direction of the first substrate, a fourth flow channel located inside the third flow channel, and a fifth flow channel in the shape of a rectangle located inside the third flow channel and surrounding the fourth flow channel. The third flow channel is connected to the first flow channel. The third flow channel, the fourth flow channel, and the fifth flow channel are in sequential communication, and the fifth flow channel is connected to the second flow channel.

2. The direct cooling plate according to claim 1, wherein: Each flow channel is provided with two branch flow channels away from the connection with the adjacent flow channel.

3. The direct cooling plate according to claim 1, characterized in that: The branch flow channels are arranged along the length direction of the first substrate or along the width direction of the first substrate. The multiple branch flow channels arranged at intervals along the length direction of the first substrate are arranged at equal intervals, and the multiple branch flow channels arranged at intervals along the width direction of the first substrate are arranged at equal intervals.

4. The direct cooling plate according to claim 1, characterized in that: The longitudinal cross-sectional area of the branch flow channels is 18 - 20 square millimeters.

5. The direct cooling plate according to claim 1, wherein: The fourth flow channel includes a fifth connection channel and a wavy connection channel connected to the fifth connection channel. The fifth connection channel is connected to the fourth connection channel, and the wavy connection channel is connected to the fifth flow channel.

6. Energy storage battery pack, comprising multiple groups of battery modules, characterized in that: It further includes the direct cooling plate according to any one of claims 1 - 5, and further includes a second substrate. The second substrate is a flat plate. The first substrate and the second substrate are connected by stamping and brazing, and the battery module is attached to the surface of the second substrate.

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