Battery pack series labyrinth cold plate and battery pack

Abstract

The invention relates to the field of liquid cooling heat dissipation, in particular to a battery pack series connection labyrinth cold plate and a battery pack, the battery pack series connection labyrinth cold plate comprises a liquid cooling plate body, the liquid cooling plate body is provided with a first flow channel circling inwards and a second flow channel circling outwards, and the first flow channel and the second flow channel are arranged in parallel at an interval; the adjacent first flow channels and second flow channels are located below the same battery cell, the first flow channels and the second flow channels are spirally arranged and are parallel to each other at intervals, cooling liquid enters from any flow channel and flows out from the other flow channel, the paths are the same, and the heat dissipation effects are the same, so that the first flow channels and the second flow channels can be used as inlet and outlet flow channels of the cooling liquid; the problem of cooling effect reduction caused by wrong connection of inlets and outlets is avoided; meanwhile, the first flow channels and the second flow channels are connected in series, so that original gas in the flow channels can be exhausted, and the whole flow channels are filled with the cooling liquid, so that the contact area between the cooling liquid and the cold plate is increased, and the cooling effect of the cold plate on the battery cell is better.

Description

Technical Field

[0001] The present invention relates to the field of liquid cooling and heat dissipation, and in particular to a battery pack series-connected labyrinth cold plate and a battery pack. Background Art

[0002] As a form of energy storage, electrochemical energy storage is widely used on the power generation side, the grid side and the user side. The battery pack is the basic component unit of electrochemical energy storage. Each battery pack contains multiple single cells. Each cell will inevitably heat up during the charging and discharging process. At this time, an effective thermal control solution will directly determine the safety of the battery pack. There are two main existing thermal control methods, one is heat dissipation through air cooling, and the other is liquid cooling. Liquid cooling is also the mainstream heat dissipation method on the market. Compared with air cooling, liquid cooling has higher heat dissipation efficiency and better temperature uniformity.

[0003] When the same coolant is used, the design of the cold plate flow channel is often the key to determining the performance of a cold plate. Conventional cold plates have the following problems. First, in order to reduce costs, the flow channel will not be vacuumed before injecting coolant. The cold plate flow channels used in the prior art are mostly parallel flow channels, with many branches in parallel. The inlet is located in the middle of multiple parallel branches, and the outlet is located on one side of the parallel branch. When filling the coolant, after the branch close to the inlet is filled, the coolant is easy to flow back into the branch far away from the inlet, blocking the gas, leaving some gas inside the branch, squeezing the coolant space, and the coolant cannot fill the entire flow channel. , reducing the contact area between the coolant and the battery pack, affecting the heat dissipation performance. At the same time, the coolant outlet of this parallel cold plate is located on one side of the parallel branch. The wrong connection of the inlet and outlet can easily make the coolant unable to fill the farther branch, thereby reducing the heat dissipation performance; the second is to use an S-shaped flow channel cold plate with the inlet and outlet at both ends. The coolant flows in the flow channel, but because the coolant gradually absorbs heat, the temperature difference of the coolant near the inlet and outlet is large, the battery cell near the flow channel inlet drops sharply, and the battery cell near the flow channel outlet drops slightly, which can easily lead to a large temperature difference between the battery cells at the flow channel inlet and outlet, and poor temperature uniformity of the battery cells inside the battery pack, affecting the service life of the battery pack. Summary of the invention

[0004] In order to overcome the deficiencies of the prior art, one of the objectives of the present invention is to provide a battery pack series labyrinth cold plate to solve the problem that the gas in the flow channel of the existing cold plate cannot be discharged, affecting the heat dissipation performance and the temperature uniformity effect is poor.

[0005] To achieve the above-mentioned objectives, the present invention provides a battery pack series labyrinth cold plate, comprising a liquid cooling plate body, on which a first flow channel spiraling inward and a second flow channel spiraling outward are provided, the first flow channel and the second flow channel being arranged in parallel with each other; adjacent first flow channel and second flow channel are both located under the same battery cell.

[0006] Principle and beneficial effects of the technical solution: 1) The first flow channel and the second flow channel are both spirally arranged and spaced apart from each other in parallel. The coolant enters from any flow channel and flows out from the other flow channel. The paths are the same and the heat dissipation effect is the same. Therefore, the first flow channel and the second flow channel can both be used as inlet and outlet channels for the coolant. The inlet and outlet can be selected at will, effectively avoiding the problem of misconnecting the inlet and outlet and reducing the cooling effect.

[0007] 2) In the labyrinth cold plate flow channel solution of the present invention, the first flow channel and the second flow channel are both in series, which can discharge the original gas in the flow channel so that the coolant fills the entire flow channel, thereby increasing the contact area between the coolant and the cold plate, so that the cold plate has a better cooling effect on the battery cell.

[0008] 3) The labyrinth cold plate flow channel of the present invention is designed by spiral flow channel, so that the first flow channel and the second flow channel are arranged in parallel at intervals, so that the flow channels across the two sides of the bottom of a battery cell are one inlet and one outlet. The temperature of the incoming coolant is lower, while the temperature of the outgoing coolant is higher. Both of them dissipate heat to the battery cell at the same time, so that the heat taken away by each battery cell in the inlet area and the outlet area of ​​the flow channel is similar, effectively avoiding the coolant temperature gradient that causes a large temperature difference between each battery cell. The labyrinth flow channel solution can achieve a uniform temperature performance of the battery cell within 2°C.

[0009] 4) The labyrinth cold plate flow channel of the present invention allows two flow channels, one for inlet and one for outlet, to flow under the same battery cell. The coolant in and out of the flow channels can take away the heat of the battery cell between the inlet area and the outlet area, further improving the cooling effect.

[0010] As a preferred embodiment of the present invention, an intermediate flow channel is provided in the middle of the liquid cooling plate body, the intermediate flow channel is used to connect the first flow channel and the second flow channel, and the intermediate flow channel is provided with a plurality of parallel branch flow channels.

[0011] Beneficial effect: The intermediate flow channel is used to connect the first flow channel and the second flow channel. The multiple parallel branch flow channels are used to increase the contact area between the coolant and the battery pack, thereby improving the heat dissipation effect on the intermediate battery cell. At the same time, the branch flow channels also reduce the flow rate, take away more heat, and further improve the heat dissipation effect.

[0012] As a preferred embodiment of the present invention, interfaces of the first flow channel and the second flow channel are located on the same side.

[0013] Beneficial effect: The interfaces of the first flow channel and the second flow channel are located on the same side, which makes it easier to connect with the pipeline of the coolant unit and is also easier to install and maintain.

[0014] As a preferred embodiment of the present invention, an extension portion is provided at the interface of the second flow channel, and the extension portion and the first flow channel are spaced apart and arranged in parallel, so that the number of the side flow channels is an even number.

[0015] Beneficial effect: The extension portion of the second flow channel is used to extend the second flow channel, so that the flow channels on this side are an even number. No matter how many battery cells are arranged, there are two flow channels, one inlet and one outlet, under each battery cell, so that the temperature balance effect between each battery cell is better.

[0016] As a preferred embodiment of the present invention, the first flow channel and the corresponding positions of the positive electrode and the negative electrode of the battery pack are all provided with outwardly protruding bending sections.

[0017] Beneficial effect: The bending section corresponds to the positive and negative electrodes of the battery pack. The heat generated by the positive and negative electrodes is relatively high. The provision of the bending section allows the flow channel to cover the bottom of the positive and negative electrodes, thereby improving the heat dissipation effect near the positive and negative electrodes.

[0018] As a preferred embodiment of the present invention, the cross-sectional area of ​​one side of the bending section is smaller than the cross-sectional area of ​​the other side; the side of the bending section with a larger cross-sectional area corresponds to the positive and negative electrodes of the battery pack.

[0019] Beneficial effect: The cross-sectional areas on both sides of the bending section are different. The side with a larger cross-sectional area corresponds to the positive and negative electrodes of the battery pack. The flow rate is slower when the cross-sectional area is larger, and the contact area with the positive and negative electrodes becomes larger, which can take away more heat and improve the heat dissipation effect; while the side with a smaller cross-sectional area can increase the flow rate of the coolant, allowing it to quickly pass through the position where heat dissipation is not required.

[0020] As a preferred embodiment of the present invention, the bending section is located on the outer circle of the first flow channel.

[0021] Beneficial effect: The bending section is located on the outer circle of the first flow channel, so that the coolant can enter the bending section first. The coolant has a lower temperature when entering, and can bring out more heat from the positive and negative electrodes, thereby improving the heat dissipation effect.

[0022] As a preferred embodiment of the present invention, the liquid cooling plate body is formed by stamping a thin plate, a sealing plate is arranged above the liquid cooling plate body, and the sealing plate and the liquid cooling plate body are brazed to form an integrated structure.

[0023] Beneficial effect: In the liquid cooling plate body, the sealing plate is used to cover the liquid cooling plate body to close its upper surface, and the flow channel is both a flow path for the coolant and a reinforcing rib of the sealing plate, which can effectively improve the rigidity of the cold plate.

[0024] A second object of the present invention is to provide a battery pack, which uses the battery pack connected in series with a labyrinth cold plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0026] Figure 1 It is a schematic structural diagram of an embodiment of a battery pack in series with a labyrinth cold plate of the present invention.

[0027] Figure 2 This is an exploded view of the liquid cooling plate body of the battery pack series labyrinth cold plate embodiment of the present invention.

[0028] Figure 3 This is an assembly diagram of a battery pack and a liquid cooling plate body in an embodiment of a battery pack connected in series with a labyrinth cooling plate of the present invention.

[0029] Figure 4 This is a graph showing the actual results of the temperature measurement of the battery cells in an embodiment of the battery pack of the present invention connected in series with a labyrinth cold plate.

[0030] The figure numbers in the drawings of the specification include: 1 liquid cooling plate body, 2 first flow channel, 2-1 bending section, 3 second flow channel, 3-1 extension part, 4 middle flow channel, 4-1 branch flow channel, 5 interface, 6 sealing plate, 7 battery pack. DETAILED DESCRIPTION

[0031] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the embodiments of the present invention, and should not be construed as limiting the present invention.

[0032] In the description of the embodiments of the present invention, it should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0033] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0034] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0035] Embodiment 1 As attached Figure 1 As shown, the present invention provides a battery pack series labyrinth cold plate: comprising a liquid cooling plate body 1, on which a first flow channel 2 spiraling inwardly and a second flow channel 3 spiraling outwardly are arranged, the first flow channel 2 and the second flow channel 3 are arranged in parallel at intervals; the adjacent first flow channel 2 and the second flow channel 3 are both located under the same battery cell; an intermediate flow channel 4 is arranged in the middle of the liquid cooling plate body 1, the intermediate flow channel 4 is used to connect the first flow channel 2 and the second flow channel 3, and the intermediate flow channel 4 is provided with a plurality of parallel branch flow channels 4-1; the entire flow channel scheme is that the first flow channel 2 spiraling inwardly is connected to the intermediate flow channel 4, the intermediate flow channel 4 is connected to the second flow channel 3 spiraling outwardly, the first flow channel 2 and the second flow channel 3 are arranged in an alternate manner at intervals, so as to realize a battery cell bottom. The flow channels on both sides of the cross section are one inlet and one outlet. The temperature of the incoming coolant is lower, while the temperature of the outgoing coolant is higher. Both of them dissipate heat to the battery cells at the same time, so that the heat taken away by each battery cell in the inlet area and the outlet area of ​​the flow channel is similar, effectively avoiding the coolant temperature gradient that causes a large temperature difference between each battery cell; at the same time, except that the middle flow channel 4 is provided with a branch, the other positions are all in series, which can effectively discharge the gas in the flow channel, increase the contact area between the coolant and the cold plate, and make the cold plate have a better cooling effect on the battery cell; at the same time, two flow channels, one inlet and one outlet, flow under the same battery cell, and the coolant in and out of the flow channels can take away heat, further improving the cooling effect; and the multiple branch flow channels 4-1 of the middle flow channel 4 are used to increase the contact area between the coolant and the battery pack 7, and improve the heat dissipation effect on the middle battery cell.

[0036] As attached Figure 1 As shown, the interface 5 of the first flow channel 2 and the second flow channel 3 is located on the same side, and an extension portion 3-1 is provided at the interface of the second flow channel 3. The extension portion 3-1 and the first flow channel 2 are spaced and parallel to each other, so that the number of flow channels on this side is an even number; the interface 5 of the first flow channel 2 and the second flow channel 3 is located on the same side, which can be more convenient for connection with the coolant unit pipeline, and is also convenient for installation, maintenance and replacement, and the provision of the extension portion 3-1 can extend the second flow channel 3, so that the interfaces 5 of the two flow channels are on the same side, and the number of flow channels on this side is an even number. No matter how many battery cells are arranged, there are two flow channels, one inlet and one outlet, under each battery cell, so that the temperature balance effect between each battery cell is better.

[0037] As attached Figure 1As shown, the first flow channel 2 and the positions corresponding to the positive and negative electrodes of the battery pack 7 are all provided with outwardly protruding bending sections 2-1, and the cross-sectional area of ​​one side of the bending section 2-1 is smaller than the cross-sectional area of ​​the other side; the side with a larger cross-sectional area of ​​the bending section 2-1 corresponds to the positive and negative electrodes of the battery pack 7, and the bending section 2-1 is located on the outer circle of the first flow channel 2; the bending section 2-1 corresponds to the positive and negative electrodes of the battery pack 7, and the setting of the bending section 2-1 allows the flow channel to cover the bottom of the positive and negative electrodes to dissipate heat for the positive and negative electrodes; the cross-sectional areas on both sides of the bending section 2-1 are different, and the side with a larger cross-sectional area corresponds to the positive and negative electrodes of the battery pack 7. The flow rate is slower due to the larger cross-sectional area. The larger the contact area with the positive and negative electrodes, the more heat can be taken away and the heat dissipation effect can be improved; and the side with a smaller cross-sectional area can increase the flow rate of the coolant, allowing it to quickly pass through the position where heat dissipation is not required; the bending section 2-1 is located on the outer circle of the first flow channel 2, so that the coolant can enter the bending section 2-1 first when entering. The temperature of the coolant is lower when entering, and more heat can be taken away from the positive and negative electrodes, thereby improving the heat dissipation effect; the heat generated by the positive and negative electrodes is relatively high. By setting the bending section 2-1 on the outer circle of the first flow channel 2 and changing the cross-sectional area of ​​the bending section 2-1, the heat dissipation effect on the positive and negative electrodes is effectively improved.

[0038] As attached Figure 2 and Figure 3 As shown, in this embodiment, the liquid cooling plate body 1 is formed by stamping a thin plate, and a sealing plate 6 is arranged above the liquid cooling plate body 1. The sealing plate 6 and the liquid cooling plate body 1 are brazed to form an integrated structure. In the liquid cooling plate body 1, the sealing plate 6 is used to cover the liquid cooling plate body 1 to close its upper surface, and the flow channel is both a flow path for the coolant and a reinforcement rib of the sealing plate 6, which can effectively improve the rigidity of the cold plate.

[0039] Attached Figure 4 Explanation: The first figure is a temperature curve diagram of 28 battery cells during charging and discharging. The vertical axis is temperature and the horizontal axis is time. Using the cold plate of this solution, the temperature difference of each battery cell is within 2°C. The second figure is a temperature difference curve diagram, that is, the difference between the maximum temperature and the minimum temperature during the charging and discharging process.

[0040] Embodiment 2 As attached Figure 3 As shown: Based on the first embodiment, the present invention also provides a battery pack, which adopts the battery pack connected in series with the labyrinth cold plate, the battery cells of the battery pack correspond to the liquid cold plate body, and there are two flow channels under each battery cell, which improves the heat dissipation effect while making the heat dissipation effect of each battery cell similar, thereby improving the temperature uniformity.

[0041] The preferred implementation modes of the present application are described in detail above in conjunction with the accompanying drawings. Typical known structures and common knowledge technologies in the preferred implementation modes are not described in detail here. Ordinary technicians in the relevant field can improve and implement the technical solutions of the present invention based on their own abilities under the inspiration given by the present implementation modes. Some typical known structures, known methods or common knowledge technologies should not become obstacles for ordinary technicians in the relevant field to implement the present application.

[0042] The scope of protection required by this application shall be based on the contents of its claims, and the contents recorded in the invention content, specific implementation methods and drawings of the specification shall be used to interpret the claims.

[0043] Within the technical concept of the present application, several modifications may be made to the specific implementation methods of the present application, and these modified specific implementation methods should also be regarded as within the protection scope of the present application.

Claims

1. A battery pack series labyrinth cold plate, comprising a liquid cold plate body, characterized in that: The liquid cooling plate body is provided with a first flow channel spiraling inwardly and a second flow channel spiraling outwardly, the first flow channel and the second flow channel are arranged in parallel with each other; the adjacent first flow channel and the second flow channel are both located under the same battery cell.

2. The battery pack series labyrinth cold plate according to claim 1, characterized in that: An intermediate flow channel is arranged in the middle of the liquid cooling plate body, and the intermediate flow channel is used to connect the first flow channel and the second flow channel. The intermediate flow channel is provided with a plurality of parallel branch flow channels.

3. The battery pack series labyrinth cold plate according to claim 1, characterized in that: The interfaces of the first flow channel and the second flow channel are located on the same side.

4. The battery pack series labyrinth cold plate according to claim 1, characterized in that: An extension portion is provided at the interface of the second flow channel, and the extension portion and the first flow channel are spaced apart and parallel to each other, so that the number of the side flow channels is an even number.

5. The battery pack series labyrinth cold plate according to claim 1, characterized in that: The first flow channel and the corresponding positions of the positive electrode and the negative electrode of the battery pack are all provided with bending sections protruding outwards.

6. The battery pack series labyrinth cold plate according to claim 5, characterized in that: The cross-sectional area of ​​one side of the bending section is smaller than the cross-sectional area of ​​the other side; the side of the bending section with a larger cross-sectional area corresponds to the positive and negative electrodes of the battery pack.

7. The battery pack series labyrinth cold plate according to claim 6, characterized in that: The bending section is located on the outer circle of the first flow channel.

8. The battery pack series labyrinth cold plate according to claim 1, characterized in that: The liquid cooling plate body is formed by stamping a thin plate, a sealing plate is arranged above the liquid cooling plate body, and the sealing plate and the liquid cooling plate body are brazed to form an integrated structure.

9. A battery pack, characterized in that: A battery pack as described in any one of claims 1 to 8 is used in series with a labyrinth cold plate.

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