TWI750543B - Battery module cooling cover - Google Patents

Abstract

The present invention provides a heat dissipation cover for a battery module, comprising: a cover body with a fluid flow space inside the cover body, a fluid inlet at one end of the cover body and a fluid outlet at the other end; The fluid inlet and the fluid outlet communicate with the fluid flow space, the lower surface of the cover body is thermally conductively contacted with the positive and negative copper bars of a battery module; a plurality of cylindrical fins are arranged on the The fluid flow space is in thermally conductive contact with the cover plate body.

Description

Battery module cooling cover

The present invention is related to battery heat dissipation technology, and particularly relates to a battery module heat dissipation cover plate used for a battery module composed of square-can type cells.

In an electric vehicle battery pack, rapid charging or the flow of electrons at high loads will generate a lot of heat, and too much heat can damage the battery. Therefore, in order to make the electric vehicle battery operate in the most efficient way and maximize its life, an effective cooling system is required. According to different cooling designs, it can be divided into air-cooled, such as Nissan's Leaf; or liquid-cooled, such as Chevrolet Volt. Both General Motors and Tesla Motors use liquid cooling. Because battery life depends on the thermal management system, as electric vehicle manufacturers introduce higher specification charging power to shorten the charging time, thermal management systems should play a greater role in suppressing the large amount of heat that is usually removed from the battery. Liquid cooling is the most widely used.

Both General Motors and Tesla's thermal management use liquid ethylene glycol as a coolant, similar to the fluid used in traditional car engine cooling systems. Glycol flow channels are distributed throughout the battery pack to cool all cells. Tesla's patent application for a cooling system based on ribbon metal cooling tubes that run throughout The battery pack directly contacts the wall of the "cylindrical cell" to take away heat. This design is a thermal management system design for a single large-scale battery pack, and is difficult to apply to a modular battery system that is divided into parts and a square can type of cell. Surface heat dissipation. GM uses "soft pack-shaped" cells, each of which is liquid-cooled by an aluminum cooling plate sandwiched between the cells. There are five separate coolant paths through the cooling plate in parallel in the aluminum cooling plate. Each pouch cell is then housed in a plastic frame. The frame with the cooling plate is then stacked vertically to make the entire battery pack. There is a pipeline connection between the plate and the heat sink to form a complete liquid cooling circuit. If the single battery cell in the middle needs to be repaired, the pipeline wiring involved is complicated, and there is a leakage problem after the connection is disconnected.

The domestic Xing Mobility relies on "cylindrical" cells immersed in a non-conductive liquid to directly dissipate heat. There is no need to design a water-cooled flow channel. The flame can be suppressed by immersing in a high-boiling liquid. The building blocks are used between the battery modules. The stacking design, but how to prevent the leakage of the whole box is a big challenge. In addition, this lithium battery module mainly relies on the expensive 3M ^TM Novec ^TM liquid to dissipate heat, and the cost is quite high, although this method is applicable For square-can type batteries, the cost is relatively high, and it is only suitable for high-priced vehicles. For example, Xing Mobility applies it to electric sports cars.

In order to solve the shortcomings of the prior art, the present invention provides a battery module heat dissipation cover. The present invention utilizes the hollow battery module heat dissipation cover to design fins of different sizes and different density to achieve the drainage effect. this invention The battery module heat dissipation cover can be adapted to various sizes and types of battery modules, and the internal structure design of the battery module does not need to be changed.

The present invention relates to a heat dissipation cover for a battery module, comprising: a cover body with a fluid flow space inside the cover body, a fluid inlet at one end of the cover body and a fluid outlet at the other end. The fluid inlet and the fluid outlet communicate with the fluid flow space, the lower surface of the cover body is thermally conductively contacted with the positive and negative copper bars of a battery module; a plurality of cylindrical fins are arranged on the The fluid flow space is in thermally conductive contact with the cover plate body.

In one embodiment of the present invention, the cover plate body is made of aluminum, and the outer surface of the cover plate body in contact with the battery module is surface-treated (eg, hard anodized) to prevent conductivity.

In an embodiment of the present invention, a layer of thermally conductive silicone pad is provided between the cover body and the battery module.

In one embodiment of the present invention, the fluid flow space has a flowing liquid, and the flowing liquid is water, or a mixed liquid of water and ethylene glycol, or a liquid with cooling effect.

In an embodiment of the present invention, the cylindrical fins are relatively sparsely distributed at the local heat-generating locations of the battery module, and the distribution density (density) is 0.5-0.625 times that of the non-local heat-generating locations.

The above summary and the following detailed description and accompanying drawings are all for the purpose of further illustrating the manners, means and methods adopted by the present invention to achieve the intended purpose. effect. The other objects and advantages of the present invention will be explained in the following descriptions and drawings.

11‧‧‧Battery module

111‧‧‧Rectangular Can Cell

112‧‧‧Copper bar

12‧‧‧Battery module cooling cover

21‧‧‧Cover body

211‧‧‧Fluid flow space

212‧‧‧Fluid inlet

213‧‧‧Fluid outlet

214‧‧‧Lower surface

22‧‧‧Cylinder fins

31‧‧‧Battery module cooling cover

32‧‧‧Thermal Silicone Pad

33‧‧‧Copper bar

34‧‧‧Cells

41‧‧‧Cylinder fins

41A‧‧‧Sparse

41B‧‧‧Close place

42‧‧‧Local heating surface

FIG. 1 is a schematic diagram showing the use state of the heat dissipation cover of the battery module of the present invention.

FIG. 2 is a structural diagram of the first embodiment of the heat dissipation cover plate of the battery module of the present invention.

FIG. 3 is a schematic diagram of an embodiment of the thermally conductive silicone pad of the present invention.

FIG. 4 is a schematic diagram of an embodiment of the distribution of cylindrical fins of the present invention.

The following describes the embodiments of the present invention with specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

FIG. 1 is a schematic diagram of the use state of the battery module heat dissipation cover plate of the present invention. The battery module 11 referred to in the present invention is composed of square can-shaped cells, that is, a plurality of rectangular can-shaped cells 111 are arranged and integrated in a In the square box of the battery module 11, as shown in FIG. 1, the copper bar 112 connecting the positive and negative terminals of the battery module 11 in series is usually located at the uppermost edge of the battery module 11, and due to the relationship of contact resistance, usually It is the heating point of the battery module 11. The battery module heat dissipation cover plate 12 of the present invention is used as the upper cover of the battery module 11. After being directly covered, it can contact the heating surface of the series/parallel copper bars 112, and conduct its ohmic heat to the battery. The circulating fluid in the module heat dissipation cover plate 12 is used to control the high temperature of the battery module 11 to prevent the occurrence of thermal runaway.

FIG. 2 is the first embodiment of the heat dissipation cover plate of the battery module according to the present invention. As shown in the structure diagram, this embodiment includes: a cover body 21 with a fluid flow space 211 inside the cover body, a fluid inlet 212 at one end of the cover body and a fluid outlet 213 at the other end, the fluid inlet 212 and the fluid outlet 213 are in communication with the fluid flow space 211, and the lower surface 214 of the cover body 21 is in thermally conductive contact with the positive and negative copper bars of a battery module (refer to FIG. 1); a plurality of cylindrical fins The fins 22 , the cylindrical fins 22 are disposed in the fluid flow space 211 and have thermal conductive contact with the cover body 21 .

In one embodiment of the present invention, the cover plate body is made of aluminum. In order to avoid short circuit caused by contact between the aluminum cover plate body and the copper bars, the surface of the aluminum cover plate body can be converted into Non-conductor, or as shown in FIG. 3 , by using a thermally conductive silicone pad 32 as the thermal conductive medium between the battery module heat dissipation cover 31 and the battery module copper bar 33, the heat generated by the battery core 34 is upward (in the direction of FIG. 3 ). whichever is the case) is transmitted to the battery module heat dissipation cover 31 through the thermally conductive silicone pad 32, while also taking into account the insulating effect.

In one embodiment of the present invention, the cylindrical fins can be evenly distributed in the fluid flow space to dissipate heat on a large heating surface. However, in practical application, the heating surface of the battery module is not evenly distributed, but there are many local areas. At this time, the density of the fins can be changed to guide relatively more fluid to dissipate heat on the local heating surface.

In one embodiment of the present invention, the design of the present invention for locally changing the density of fins is as follows:

In a fluid space, the diameter D , the height Z and the number N of cylindrical fins (1) are evenly distributed in the original X*Y area, and the overall fin coverage is:

An existing local area x * y is a heating surface, the number of fins in this heating surface x * y area is N 1, and the contact area between the fins and the fluid in this local area is:

Original contact area = N 1 × D × π × Z

Change the fin design of the local heating surface into a cylindrical fin (2), its diameter d , height Z, number n , and should comply with the following two principles: (1) After changing the design, the relationship between the fin and the fluid should be Later Contact Area" needs to be equal to or greater than the "Original Contact Area". (2) The "partial fin coverage" after changing the design should be smaller than the "overall fin coverage", for example, 0.625 times or 0.5 times. The calculation is as follows:

Later contact area = n × d × π × Z

Please refer to FIG. 4 , which is a schematic diagram of an embodiment of the distribution of the cylindrical fins of the present invention. In this embodiment, the distribution of the cylindrical fins 41 has a relatively sparse part 41A and a relatively dense part 41B, corresponding to the copper bars of the battery module The local heating surface 42 (as shown in the dotted line box in Figure 4), thinning the distribution of fins in this local area can increase the water flow through this area, and improve the heat dissipation of the local heating surface when the contact area remains unchanged. Effect. This type of design is specially used for square can type battery modules to solve the liquid cooling method of local series/parallel copper row heating plane.

Therefore, the present invention provides a battery module heat dissipation cover. The present invention utilizes the hollow battery module heat dissipation cover to design different sizes and different sizes inside. The fins with the same density can achieve the drainage effect. This design can guide relatively more fluid to the heat-generating area. Without reducing the contact area between the fins and the liquid, the local heat dissipation effect is enhanced, and the battery The module heat dissipation cover is applied to the heating plane of the local series/parallel copper bars of the square can type battery module. The liquid cooling plate with cylindrical fins evenly distributed can help the square tank type battery module from the original high temperature of 51 ℃ to 36 ℃. The local thinning of the fin distribution can effectively increase the flow of coolant and locally strengthen the heat dissipation of hot spots Effect. The battery module heat dissipation cover plate of the present invention has a simple structure, can be adapted to various sizes and types of battery modules, does not need to change the internal structure design of the battery module, and has no fear of leakage of the cooling liquid to the battery module cells. Use flexibility and reliability.

The above-mentioned embodiments are only used to illustrate the features and effects of the present invention, and are not intended to limit the scope of the essential technical content of the present invention. Anyone skilled in the art can make modifications and changes to the above embodiments without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be as listed in the patent application scope described later.

21‧‧‧Cover body

211‧‧‧Fluid flow space

212‧‧‧Fluid inlet

213‧‧‧Fluid outlet

214‧‧‧Lower surface

22‧‧‧Cylinder fins

Claims (6)

A battery module heat dissipation cover plate, comprising: a cover plate body with a fluid flow space inside the cover plate body, a fluid inlet at one end of the cover plate body and a fluid outlet at the other end, the fluid inlet and the fluid The outlet communicates with the fluid flow space, the lower surface of the cover body is thermally conductively contacted with the positive and negative copper bars of a battery module; a plurality of cylindrical fins are arranged in the fluid flow space 2. Have a thermally conductive contact with the cover body; wherein the cylindrical fins are sparsely distributed at the local heat-generating place corresponding to the battery module, which can increase the fluid flow through the local heat-generating place. Under the condition that the contact area between the sheet and the fluid remains unchanged, the heat dissipation effect of local heat generation is improved. The battery module heat dissipation cover plate according to claim 1, wherein the cover plate body is made of aluminum. The battery module heat dissipation cover plate according to claim 2, wherein the outer surface of the cover plate body in contact with the battery module is surface-treated and not conductive. The battery module heat dissipation cover plate according to claim 1, wherein a layer of thermally conductive silicone pad is provided between the cover plate body and the battery module. The heat dissipation cover plate of the battery module according to claim 1, wherein the fluid flow space has a flowing liquid, and the flowing liquid is water, or a mixture of water and ethylene glycol, or a liquid with cooling effect. The heat dissipation cover plate for a battery module according to claim 1, wherein the distribution density of the cylindrical fins at the location corresponding to the local heat generation of the battery module is 0.5-0.625 times that of the non-local heat generation location.

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