L-shaped micro-channel harmonica-shaped tube type cold plate and power battery pack

Abstract

The utility model discloses an L-shaped microchannel harmonica-shaped tube type cold plate and power battery pack, the L-shaped microchannel harmonica-shaped tube type cold plate comprises a plurality of L-shaped microchannel harmonica-shaped tube units which are arranged in parallel and at intervals, each L-shaped microchannel harmonica-shaped tube unit comprises a microchannel harmonica-shaped tube and two current collecting covers, an L-shaped cavity is formed in the microchannel harmonica-shaped tube, and the two current collecting covers are arranged in the L-shaped cavity. A plurality of partition plates are arranged in the L-shaped cavity, and the L-shaped cavity is divided into a plurality of micro-channel-level medium flow channels with triangular sections. The power battery pack is mainly composed of battery cells, L-shaped micro-channel harmonica-shaped tube type cold plates and a box body assembly, and except for the battery cell in the L-shaped micro-channel harmonica-shaped tube type cold plate located on the outermost edge, three outer surfaces of each battery cell make contact with the micro-channel harmonica-shaped tube type cold plates. The L-shaped micro-channel harmonica-shaped tube type cold plate is large in heat dissipation area, high in heat transfer efficiency and good in temperature uniformity, and the problem of heat accumulation under the working condition of a high-energy-density lithium battery can be solved.

Description

Technical Field

[0001] The utility model relates to an L-shaped micro-channel harmonica tube type cold plate and a power battery pack, belonging to the technical field of power battery cooling. Background Art

[0002] As the promotion of new energy vehicles accelerates, the market demand for power batteries has also been driven, but higher requirements have also been placed on driving range. High-energy-density batteries generate more heat. If the temperature is too high, the battery performance will decline, or even burn or explode. The current mainstream solutions are serpentine harmonica tube cold plates and parallel-flow harmonica tube cold plates, but both solutions have obvious disadvantages of poor heat exchange and complex processing technology, including:

[0003] The serpentine harmonica tube cold plate has complex pipe bending, which easily causes uneven flow of the fluid medium, resulting in a small heat transfer coefficient. The temperature difference between different parts of the tube is not large, and the heat exchange effect is relatively poor. In addition, the serpentine tube heat exchanger is bulky and requires a large space;

[0004] The inlet and outlet of the parallel flow harmonica tube cold plate are respectively on the collecting pipes on both sides of the cold plate, and the temperature uniformity is poor. Because the flow channel direction is single, the contact area between the liquid cold plate and the battery is small, and the thermal resistance is large, resulting in a large temperature difference inside the battery cell. During high current charging and discharging and low temperature heating, it has a great damage effect on battery performance.

[0005] Due to the problems of heat accumulation under high-energy-density lithium battery operating conditions, poor effect of existing heat dissipation solutions, and complex processing of existing solutions, there is an urgent need to propose a new cooling solution. Summary of the invention

[0006] The utility model aims to provide an L-shaped microchannel harmonica tube cold plate and a power battery pack, which can effectively increase the heat dissipation area, increase the fluid disturbance in the tube, and enhance the heat transfer efficiency, thereby improving the battery cooling efficiency and temperature uniformity, and solving the problem of heat accumulation under high energy density lithium battery working conditions.

[0007] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0008] L-shaped micro-channel harmonica tube cold plate, including:

[0009] A microchannel harmonica tube, wherein the outer contour of the cross section of the microchannel harmonica tube forms an L-shaped closed area, the L-shaped closed area is stretched along a straight line perpendicular to the cross section to form an L-shaped cavity, a plurality of partitions are arranged in the L-shaped cavity, and the plurality of partitions are extended along the aforementioned stretching straight line to divide the L-shaped cavity into a plurality of microchannel-level medium flow channels with triangular cross sections;

[0010] A current collecting cover, wherein the current collecting cover comprises a current collecting cavity with an L-shaped cross section, two current collecting covers are respectively connected to the left and right ends of the microchannel harmonica tube in the length direction, and the current collecting cavity is communicated with the medium flow channel;

[0011] A microchannel harmonica tube and two current collecting covers form an L-shaped microchannel harmonica tube unit. A plurality of L-shaped microchannel harmonica tube units are arranged in parallel and at intervals. Adjacent L-shaped microchannel harmonica tube units are connected through nozzles, and the connection position is at the current collecting cover.

[0012] As a solution, the microchannel harmonica tube cold plate also includes a layer partition, which is arranged in the L-shaped cavity and divides the L-shaped cavity into a plurality of mutually parallel L-shaped secondary cavities, each of which contains a plurality of microchannel-level medium flow channels with triangular cross-sections divided by the partitions.

[0013] Furthermore, the current collecting cover comprises an upper current collecting cover and a lower current collecting cover, and a current collecting cavity is formed between the upper current collecting cover and the lower current collecting cover after they are butt-jointed.

[0014] Furthermore, the area of ​​the L-shaped cross section of the manifold is larger than the cross-sectional area of ​​the L-shaped cavity.

[0015] As a solution, the collecting cover is connected to the microchannel harmonica tube by brazing.

[0016] Power battery pack, including:

[0017] L-shaped micro-channel harmonica tube cold plate;

[0018] The battery cells are installed in the intervals between adjacent L-shaped microchannel harmonica tube units in the L-shaped microchannel harmonica tube cold plate, and three outer surfaces of the battery cells are respectively in contact with the microchannel harmonica tubes in the L-shaped microchannel harmonica tube units.

[0019] Furthermore, the power battery pack also includes a box assembly, which is mainly composed of an upper box and a lower box. A groove for installing a nozzle is opened on one surface of the lower box. After the upper box and the lower box are spliced ​​together, the L-shaped microchannel harmonica tube cold plate and the battery cell are encapsulated in the cavity formed by the two.

[0020] Compared with the prior art, the utility model proposes an L-shaped microchannel harmonica tube type cold plate cooling solution to solve the problem of heat accumulation under high energy density lithium battery working conditions, and designs an L-shaped microchannel harmonica tube type direct cold plate system. The utility model has the following features:

[0021] (1) The L-shaped extruded tube is used in the microchannel harmonica tube structure design to achieve three-sided cooling of the battery cell and increase the heat dissipation area.

[0022] (2) A triangular microchannel structure is adopted in the microchannel structure design. Due to the stability of the triangle, the triangular microchannel tube has better mechanical properties than the rectangular and circular microchannel tubes.

[0023] (3) The design of the upper and lower current collecting covers is easier to process and assemble than traditional solutions, and has higher reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the exploded structure of the battery pack;

[0025] Figure 2 This is a schematic diagram of the battery pack after assembly;

[0026] Figure 3 is a schematic diagram of the L-shaped cross-section structure of a microchannel harmonica tube;

[0027] Figure 4 1 is a schematic diagram of the appearance structure of a microchannel harmonica tube;

[0028] Figure 5 is a schematic diagram of the sealing structure of the current collecting cover and the microchannel harmonica tube;

[0029] In the figure: 100 - battery cell, 200 - L-type microchannel harmonica tube unit, 210 - microchannel harmonica tube, 220 - upper current collecting cover, 230 - lower current collecting cover, 240 - nozzle, 300 - box assembly, 310 - upper box, 320 - lower box. DETAILED DESCRIPTION

[0030] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments, but it should not be understood that the scope of the subject matter described in the present invention is limited to the following embodiments. Without departing from the above-mentioned technical ideas of the present invention, various modifications, substitutions and changes made according to the common technical knowledge and customary means in the field are included in the scope of the present invention.

[0031] like Figures 1 to 5 As shown, the L-shaped microchannel harmonica tube cold plate uses multiple L-shaped microchannel harmonica tube 210 assemblies in parallel, with the inlet and outlet at both ends of the cold plate. One microchannel harmonica tube 210 and two current collecting covers form an L-shaped microchannel harmonica tube unit 200, and one current collecting cover is brazed by an upper current collecting cover 220, a lower current collecting cover 230 and a nozzle 240. The middle area of ​​the upper current collecting cover 220 and the lower current collecting cover 230 is raised in two opposite directions (refer to Figure 5The surface where the upper collecting cover 220 is connected to the nozzle 240 is convex, and the surface where the lower collecting cover 230 is connected to another nozzle 240 is also convex), so that the upper collecting cover 220 and the lower collecting cover 230 form a groove on the opposite surfaces respectively, and the two grooves are connected together to form a collecting cavity, which is connected to the inlet or outlet of the microchannel harmonica tube 210.

[0032] Figure 4 The L-shaped microchannel harmonica tube 210 can achieve cooling effect on three sides of the battery cell 100. Figure 3 The interior of the microchannel harmonica tube 210 is a plurality of triangular microchannel flow channels to enhance heat dissipation. Figure 3 The middle left picture shows a scheme without a layer partition, and the microchannel harmonica tube 210 has only one L-shaped cavity inside. Figure 3 The middle right picture shows a solution with a partition, which divides the L-shaped cavity inside the microchannel harmonica tube 210 into two L-shaped secondary cavities, and each L-shaped secondary cavity is divided into multiple microchannel flow paths with triangular cross-sections by the partition.

[0033] like Figure 1 and Figure 2 As shown, a power battery pack using an L-shaped microchannel harmonica tube cold plate includes an L-shaped microchannel harmonica tube cold plate, a battery cell 100 and a box assembly 300. A plurality of battery cells 100 are installed in the intervals between adjacent L-shaped microchannel harmonica tube units 200 in the L-shaped microchannel harmonica tube cold plate, and the three outer surfaces of the battery cells 100 are respectively in contact with the microchannel harmonica tubes 210 in the L-shaped microchannel harmonica tube unit 200. The box assembly 300 is mainly composed of an upper box 310 and a lower box 320. A notch for installing a nozzle 240 is opened on one surface of the lower box 320. After the upper box 310 and the lower box 320 are spliced, the L-shaped microchannel harmonica tube cold plate and the battery cell 100 are encapsulated in the cavity formed by the two.

[0034] In the L-shaped microchannel design of the utility model, the partition is equivalent to a plurality of ribs, which can efficiently conduct the heat of the battery to the microchannel through the ribs, and then take the heat away through liquid cooling. Since the L-shaped microchannel harmonica tube 210 has three contact surfaces with the battery cell 100, the heat dissipation area is increased, and the rib structure formed by the partition increases the fluid disturbance in the tube. At the same time, the rib structure composed of multiple partitions quickly conducts the heat of the battery cell 100 from the three contact heat-conducting surfaces to the refrigerant, thereby enhancing the heat transfer efficiency, thereby improving the battery cooling efficiency and temperature uniformity, and solving the problem of heat accumulation under high energy density lithium battery conditions.

[0035] The above are the main concepts of the present invention. All L-shaped microchannel harmonica tube cold plates and power battery packs designed based on the concepts of the present invention fall within the protection scope of the present invention.

Claims

1. L-type microchannel harmonica tube cold plate, characterized in that: include: A microchannel harmonica tube (210), wherein the outer contour of the cross section of the microchannel harmonica tube (210) forms an L-shaped closed area, the L-shaped closed area is stretched along a straight line perpendicular to the cross section to form an L-shaped cavity, a plurality of partitions are arranged in the L-shaped cavity, and the plurality of partitions are extended along the aforementioned stretching straight line to divide the L-shaped cavity into a plurality of microchannel-level medium flow channels with triangular cross sections; A current collecting cover, the current collecting cover comprising a current collecting cavity with an L-shaped cross section, the two current collecting covers being respectively connected to the left and right ends of the microchannel harmonica tube (210) in the length direction, and the current collecting cavity being in communication with the medium flow channel; A microchannel harmonica tube (210) and two current collecting covers form an L-shaped microchannel harmonica tube unit (200); a plurality of L-shaped microchannel harmonica tube units (200) are arranged in parallel and at intervals; adjacent L-shaped microchannel harmonica tube units (200) are connected via nozzles (240), and the connection position is at the current collecting cover.

2. The L-shaped microchannel harmonica tube cold plate according to claim 1, characterized in that: It also includes a layer partition, which is arranged in the L-shaped cavity and divides the L-shaped cavity into a plurality of L-shaped secondary cavities parallel to each other. Each L-shaped secondary cavity contains a plurality of medium flow channels of microchannel level and triangular cross-section divided by the partition.

3. The L-shaped microchannel harmonica tube cold plate according to claim 1, characterized in that: The current collecting cover comprises an upper current collecting cover (220) and a lower current collecting cover (230), and a current collecting cavity is formed between the upper current collecting cover (220) and the lower current collecting cover (230) after being butt-jointed.

4. The L-shaped microchannel harmonica tube cold plate according to claim 1 or 3, characterized in that: The area of ​​the L-shaped cross section of the manifold is larger than the cross-sectional area of ​​the L-shaped cavity.

5. The L-shaped microchannel harmonica tube cold plate according to claim 1, characterized in that: The current collecting cover is connected to the microchannel harmonica tube (210) by brazing.

6. A power battery pack, characterized in that: include: L-shaped micro-channel harmonica tube cold plate; A battery cell (100), wherein a plurality of battery cells (100) are installed in the intervals between adjacent L-shaped micro-channel harmonica tube units (200) in an L-shaped micro-channel harmonica tube cold plate, and three outer surfaces of the battery cell (100) are respectively in contact with the micro-channel harmonica tubes (210) in the L-shaped micro-channel harmonica tube units (200).

7. The power battery pack according to claim 6, characterized in that: The invention also comprises a box assembly (300), wherein the box assembly (300) is mainly composed of an upper box (310) and a lower box (320), a surface of the lower box (320) is provided with a notch for installing a nozzle (240), and after the upper box (310) and the lower box (320) are spliced ​​together, the L-shaped microchannel harmonica tube cold plate and the battery cell (100) are encapsulated in a cavity formed by the upper box (310) and the lower box (320).

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