Battery heat exchange plate with capillary layer and turbulence structure

Abstract

The application discloses a battery heat exchange plate with a capillary layer and a turbulence structure, and belongs to the technical field of battery thermal management. The battery heat exchange plate comprises a plate-shaped body, and a plurality of parallel heat exchange flow channels are arranged in the plate-shaped body; a capillary layer composed of felt material is arranged above the heat exchange flow channels, the lower surface of the capillary layer is in contact with refrigerant in the flow channels, and the upper surface of the capillary layer serves as a battery heat exchange interface; a plurality of communication holes in the axial direction are arranged on the partition wall surface between adjacent heat exchange flow channels and point to the capillary layer. The capillary layer is used for actively adsorbing and distributing refrigerant by capillary force, so that the heat exchange interface is ensured to be wetted; meanwhile, the refrigerant is guided to flow transversely between the flow channels through the communication holes to form turbulence, steam bubbles are broken, and the refrigerant is redistributed. The structure effectively prevents the gas jam phenomenon, improves the heat exchange efficiency and reliability, and has the advantages of simple structure and low cost.

Description

Technical Field

[0001] This application relates to battery heat exchange plates, and more particularly to a battery heat exchange plate with a capillary layer and a turbulence structure. Background Technology

[0002] In the field of battery thermal management, heat sinks utilizing refrigerants for heat exchange are a common technical solution. These heat sinks rapidly absorb heat generated by the battery through the flow or phase change of the refrigerant (such as Freon or hydrocarbons) within the channels, thereby achieving efficient temperature control. These heat sinks are typically made of metal or plastic and feature complex internal flow channel structures to promote heat exchange between the refrigerant and the battery surface. Currently, refrigerant heat sinks are widely used in electric vehicles, energy storage systems, and other applications due to their high heat exchange efficiency and fast response speed, helping to maintain the battery within its optimal operating temperature range and improving safety and lifespan.

[0003] However, the aforementioned existing technologies have significant shortcomings in practical applications, the most prominent being the "airlock" phenomenon. When the temperature in a localized area of ​​the battery heat sink becomes excessively high, the refrigerant flowing through that area may rapidly vaporize due to heat absorption, forming gas bubbles that block the narrow heat exchange channels. This airlock hinders the continuous flow of refrigerant, resulting in a lack of refrigerant replenishment downstream of the blockage point, hindering effective heat dissipation and causing the local temperature to continue to rise. The reasons for this are twofold: firstly, the flow channel design of existing heat sinks often fails to adequately consider gas expulsion mechanisms, and uneven refrigerant distribution easily leads to gas accumulation; secondly, the refrigerant's flow dynamics rely on external pumping or gravity, and after vaporization at high temperatures, the gas is difficult to remove in time, triggering a vicious cycle and even posing a risk of thermal runaway, threatening the safety of the battery system. Furthermore, existing technologies often employ complex venting structures or high-pressure systems to alleviate the airlock problem, which not only increases manufacturing costs but also complicates the processing technology.

[0004] To address the aforementioned shortcomings, developing new battery heat dissipation plate technologies is of great significance. Utility Model Content

[0005] The purpose of this application is to overcome at least one deficiency of the prior art and provide a battery heat exchange plate with a capillary layer and a turbulence structure. This battery heat exchange plate achieves this through the synergistic effect of capillary drainage and forced turbulence, ultimately significantly improving the reliability, safety and economy of the battery thermal management system.

[0006] To achieve the above objectives, this application discloses a battery heat exchange plate with a capillary layer and a turbulence structure. The battery heat exchange plate includes a plate-shaped body, in which multiple microchannels are arranged in parallel as heat exchange channels.

[0007] A capillary layer made of felt material is laid on top of the heat exchange channel. This capillary layer has good flexibility, porosity, and significant capillary liquid absorption capacity. Its lower surface is in direct contact with the refrigerant in the heat exchange channel, while its upper surface serves as the interface for supporting the battery module and exchanging heat. Through the capillary force generated by its fiber pores, the capillary layer can actively adsorb liquid refrigerant from the channel and uniformly penetrate it throughout the entire heat exchange interface, thereby providing a continuous and stable supply of cooling medium to this interface.

[0008] Furthermore, several connecting holes are formed on the partition walls between adjacent heat exchange channels, with the axes of these connecting holes pointing towards the felt layer. When the refrigerant flows within the channels, some of the refrigerant can flow laterally between different channels through these connecting holes under the influence of pressure difference, forming cross-flow turbulence. This design not only enhances the turbulence effect of the refrigerant and improves the overall heat exchange efficiency, but also destroys vapor bubbles that may form due to local overheating. Furthermore, the turbulence promotes the redistribution of the refrigerant at the bottom of the felt layer, effectively avoiding vapor lock problems caused by vapor accumulation or refrigerant flow interruption.

[0009] This application utilizes the inherent capillary properties of felt material to ensure uniform refrigerant coverage at the heat exchange interface, and combines this with a turbulence design between crossflow channels to synergistically improve the system's heat exchange reliability and thermal runaway prevention capabilities. This solution features a simple structure, inexpensive felt material that is easy to process and integrate, providing a highly efficient and economical solution for battery thermal management.

[0010] The beneficial effects listed above are not exhaustive of all advantages. Other potential beneficial effects and detailed technical implementation methods will be further disclosed in the embodiments or other descriptive sections of this application. Attached Figure Description

[0011] A better understanding of various aspects of this disclosure will be achieved by reading the following detailed description in conjunction with the accompanying drawings. The positions, dimensions, and extents of the structures shown in the drawings, etc., do not always represent actual positions, dimensions, and extents. In the drawings: Figure 1 This is a schematic diagram of the structure of one embodiment disclosed in this application.

[0012] Figure 2 yes Figure 1 Enlarged view of point A. Detailed Implementation

[0013] The present disclosure will now be described with reference to the accompanying drawings, which illustrate several embodiments of the present disclosure. However, it should be understood that the present disclosure can be presented in many different ways and is not limited to the embodiments described below; in fact, the embodiments described below are intended to make the disclosure more complete and to fully illustrate the scope of protection of the present disclosure to those skilled in the art. It should also be understood that the embodiments disclosed herein can be combined in various ways to provide further additional embodiments.

[0014] It should be understood that the same reference numerals denote the same elements in all the accompanying drawings. For clarity, the dimensions of certain features may be modified in the drawings.

[0015] It should be understood that the terminology used in this specification is for describing specific embodiments only and is not intended to limit this disclosure. All terms used in this specification (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. For the sake of brevity and / or clarity, techniques, methods, and apparatus known to those skilled in the art may not be discussed in detail; however, where appropriate, such techniques, methods, and apparatus should be considered part of this specification.

[0016] Unless otherwise specified, the singular forms “a,” “the,” and “the” used in this specification include the plural forms. The terms “comprising,” “including,” and “containing” used in this specification indicate the presence of the claimed feature but do not exclude the presence of one or more other features. The term “and / or” used in this specification includes any and all combinations of one or more of the relevant listed items. Example

[0017] See attached document Figure 1 and 2 This embodiment provides a battery heat exchange plate with a capillary layer and a turbulence structure. Its structure mainly includes a plate-shaped body 1 made of metal. Multiple parallel serpentine or straight-line channels 2 are formed within the plate-shaped body 1. Above these heat exchange channels 2, a capillary layer 3 composed of a capillary porous material is tightly adhered, such as non-woven felt made of polymer fibers, sintered metal felt, or carbon fiber felt.

[0018] Specifically, several connecting holes 4 are provided on the partition wall between adjacent heat exchange channels 2, and the axial direction of these connecting holes 4 is inclined or perpendicular to the capillary layer 3.

[0019] In addition, the plate-shaped body 1 has a liquid inlet and a liquid outlet at both ends that are connected to the heat exchange channel, which are used to connect to the external coolant circulation system. The specific connection method and sealing structure are existing technologies in the field and will not be described in detail here.

[0020] More specifically, the plate-shaped body 1 is preferably made of a material with good thermal conductivity, such as aluminum alloy or copper alloy, and is formed by extrusion, brazing, or precision machining to ensure structural strength and thermal conductivity efficiency. The cross-sectional shape of its internal heat exchange channels 2 can be rectangular, trapezoidal, or circular, and the hydraulic diameter of the channels can be selected between 1 and 3 mm according to the design flow rate and pressure drop requirements. The layout of the channels must ensure that the refrigerant can flow fully through the entire heat exchange area, avoiding flow dead zones.

[0021] The function of the capillary layer 3 is to spontaneously adsorb and transport liquid refrigerant through capillary force. Taking polypropylene nonwoven felt as an example, its thickness can be selected in the range of 0.5 mm to 2 mm, and its porosity is between 60% and 85% to ensure sufficient liquid storage space and efficient liquid transport capacity. This felt layer is fixed to the plate-shaped body 1 by high-temperature resistant thermally conductive adhesive or mechanical pressing, covering at least the heat exchange surface to ensure that its surface can fully contact the refrigerant in the flow channel. When liquid refrigerant is present in the flow channel, the felt layer will continuously adsorb the liquid into its entire porous skeleton through the strong capillary force generated by the micron-sized pores between its fibers until it reaches saturation.

[0022] This process ensures that the upper surface of capillary layer 3 is eventually wetted by a layer of liquid refrigerant, thereby transforming the traditional "point-to-line" contact heat exchange into a large-area "surface-to-surface" liquid film heat exchange, which greatly improves the uniformity and efficiency of heat exchange.

[0023] The connecting holes 4 are a key structure in this embodiment for achieving enhanced heat transfer and suppressing airlock. These channels penetrate the partition wall between adjacent flow channels, and their diameter is preferably 0.5 mm to 2 mm. They can be positioned directly opposite or slightly above the bottom of the flow channel. The axis of the channels can be perpendicular to the partition wall, or it can be designed to be inclined towards the capillary layer 3, for example, at an angle of 30 to 60 degrees to the vertical direction, so as to more effectively guide the refrigerant to impact the capillary layer 3.

[0024] When the refrigerant flows along the main channel under the driving force of the pump, due to the small pressure difference between adjacent channels, some fluid will be injected laterally from one channel to the adjacent channel through these connecting holes 4. This cross-flow generates a strong turbulence effect, which on the one hand enhances the turbulence of the fluid in the channel, thins the thermal boundary layer, and strengthens convective heat transfer; on the other hand, the impact of the fluid on the capillary layer 3 promotes the penetration and redistribution of the refrigerant in the capillary porous structure. In particular, it can promptly disperse vapor bubbles that may form at the top of the channel or the bottom of the capillary layer due to local overheating, preventing them from accumulating and growing to form gas locks.

[0025] During operation, the low-temperature refrigerant is pumped in through the inlet port and flows through each heat exchange channel 2. The heat generated by the battery is transferred to the upper surface of the capillary layer through the thermally conductive interface material, heating the refrigerant wetted in the capillary layer 3 and the refrigerant flowing in the channels. The capillary layer 3 maintains the heat exchange interface wetness through capillary action, effectively preventing local dry burning. At the same time, the cross-turbulence caused by the connecting holes 4 continuously disrupts the thermal boundary layer and removes potential air bubbles, ensuring efficient and uniform heat dissipation. Finally, the heated coolant is discharged from the outlet port, completing one cycle. This design is particularly suitable for the thermal management of electric vehicle battery modules. In actual testing, compared with traditional heat sinks without capillary layers and connecting holes, this embodiment can reduce the temperature difference between the hot spot and the average temperature by more than 40% when simulating hot spots generated by localized battery discharge at high rates, and completely eliminates the risk of thermal runaway caused by airlocks. At the same time, thanks to the low cost of the felt material and the simplification of the channel structure, the overall manufacturing cost is significantly reduced.

[0026] While exemplary embodiments of this disclosure have been described, those skilled in the art will understand that various changes and modifications can be made to the exemplary embodiments of this disclosure without departing from the spirit and scope thereof. Therefore, all changes and modifications are included within the scope of protection of this disclosure as defined by the claims. This disclosure is defined by the appended claims, and equivalents of those claims are also included.

Claims

1. A battery heat exchange plate with a capillary layer and a turbulence structure, characterized in that, include: A plate-shaped body has multiple parallel microchannels inside as heat exchange channels. The two ends of the plate-shaped body are respectively provided with liquid inlet and liquid outlet interfaces that communicate with the heat exchange channels. A capillary layer made of felt material is laid on top of the heat exchange channel. The lower surface of the capillary layer is in direct contact with the refrigerant in the heat exchange channel, and its upper surface serves as the interface for carrying the battery module and exchanging heat. Several connecting holes are formed on the partition wall of adjacent heat exchange channels, and the axis of the connecting holes points towards the capillary layer.

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