Snake-type tube battery thermal management device

Abstract

The present invention comprises a cooling tube formed in a wave shape to contact the sides of a plurality of battery cells, a first manifold provided on one side of the cooling tube for introducing cooling water into the cooling tube, and a second manifold provided on the other side of the cooling tube for discharging cooling water from the cooling tube, wherein the cooling tube has a flat oval cross-sectional shape and a cooling water flow path formed inside, and includes a first surface that contacts the battery cell and a second surface that is spaced apart from the first surface and forms the cooling water flow path, wherein the cooling water flow path is eccentrically arranged toward the first surface side that contacts the battery cell, spaced apart from the geometric center of the flat oval cross-section, and the tube thickness on the first surface side is formed to be thinner than the tube thickness on the second surface side, and an insulating coating layer for electrical insulation with respect to the battery cell is formed on the surface of the cooling tube, and a heat transfer pad formed of a material having electrical insulation properties, thermal conductivity, and elasticity is located between the battery cell and the insulating coating layer, and the cooling water comprises water and a glycol-based component. The present invention provides a snake-shaped tube-type battery thermal management device characterized by comprising 60 to 85 parts by weight of ethylene glycol and 15 to 40 parts by weight of propylene glycol as glycol components.

Description

Technology Field

[0001] The present invention relates to battery thermal management technology, and more specifically, to a battery thermal management device that performs cooling and heating of battery cells using a snake-shaped cooling tube disposed in contact with a plurality of cylindrical battery cells. Background Technology

[0002] High-energy-density battery packs are widely used in various industrial sectors, such as electric vehicles, hybrid vehicles, and energy storage systems. These battery packs have a structure composed of multiple battery cells, and heat is inevitably generated during the charging and discharging process.

[0003] If the heat generated in battery cells is not effectively controlled, problems such as cell performance degradation, shortened lifespan, and reduced safety may occur; therefore, battery thermal management is recognized as a core technology for ensuring the reliability of battery systems.

[0004] In particular, for battery packs containing cylindrical battery cells, heat tends to concentrate upward along the height direction due to the shape characteristics of the cells; consequently, temperature variations between the upper and lower parts of the battery pack are prone to occur. These temperature variations lead to uneven degradation rates between cells, which ultimately degrades the overall performance and lifespan of the battery pack.

[0005] Conventional battery thermal management technologies, such as cooling plate, cooling channel, and air cooling methods, have been proposed; however, these methods often suffer from insufficient heat transfer efficiency due to limited contact areas with the sides of cylindrical battery cells or reliance on localized contact. Furthermore, the cooling channels fail to provide uniform heat exchange across the entire height of the battery cell, limiting the ability to effectively resolve temperature variations within the battery pack.

[0006] Meanwhile, although the importance of technology for heating batteries for use in low-temperature environments or for pre-conditioning before charging is increasing, conventional technology has problems such as difficulty in efficiently performing cooling and heating within the same structure, or difficulty in securing a uniform temperature distribution across the entire battery cell during heating.

[0007] Therefore, there is a continuous demand for a new type of battery thermal management device that can make contact with the sides and a wide area of ​​the cylindrical battery cell, enable uniform cooling and heating along the height direction of the battery cell, and efficiently perform both cooling and heating functions. The problem to be solved

[0008] The present invention has been devised to solve the above-mentioned problems and aims to provide a battery thermal management device that improves heat transfer efficiency by providing a cooling structure capable of contacting the side of a battery cell with a large surface area in a battery pack including a cylindrical battery cell. means of solving the problem

[0009] The snake-type tube-type battery thermal management device of the present invention comprises a cooling tube formed in a wave shape to contact the side of a plurality of battery cells of the present invention, a first manifold provided on one side of the cooling tube to introduce cooling water into the cooling tube, and a second manifold provided on the other side of the cooling tube to discharge cooling water from the cooling tube, wherein the cooling tube has a flat oval cross-sectional shape and a cooling water flow path formed inside, and comprises a first surface that contacts the battery cell and a second surface that is spaced apart from the first surface to form the cooling water flow path, wherein the cooling water flow path is eccentrically arranged toward the first surface side that contacts the battery cell, spaced apart from the geometric center of the flat oval cross-section, and the tube thickness on the first surface side is formed to be thinner than the tube thickness on the second surface side, and an insulating coating layer for electrical insulation with respect to the battery cell is formed on the surface of the cooling tube, and a heat transfer pad formed of a material having electrical insulation properties, thermal conductivity, and elasticity is positioned between the battery cell and the insulating coating layer. The above cooling water comprises water and a glycol-based component, and the glycol-based component is characterized by comprising 60 to 85 parts by weight of ethylene glycol and 15 to 40 parts by weight of propylene glycol.

[0010] The side of each of the above battery cells may be characterized by being in surface contact with the cooling tube.

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[0013] delete Effects of the invention

[0014] According to the present invention, a snake-shaped cooling tube having a flat oval cross-section is arranged to make surface contact with the side of a cylindrical battery cell, thereby increasing the contact area between the cooling tube and the battery cell and reducing the heat transfer resistance, which has the effect of improving the cooling and heating efficiency of the battery cell.

[0015] And according to the present invention, the cooling tube is formed in a snake shape along the arrangement of the battery cells so that the cooling water or heating fluid flows over the entire height direction of the battery cells, thereby reducing the temperature difference between the upper and lower parts of the battery cells and maintaining a more uniform temperature distribution inside the battery pack.

[0016] In addition, according to the present invention, the cooling water passage inside the cooling tube is eccentrically positioned toward the outer surface side that contacts the battery cell, thereby shortening the heat transfer path between the battery cell and the cooling water passage and improving responsiveness to cooling and heating.

[0017] In addition, according to the present invention, by providing an insulating coating layer and a heat transfer pad on the outer surface of the cooling tube, electrical insulation with respect to the battery cell is ensured and clearance caused by vibration or assembly tolerances is absorbed, thereby simultaneously improving electrical safety and structural stability.

[0018] In addition, according to the present invention, by selectively controlling the inflow position and flow direction of the cooling water, uniform heat exchange can be achieved throughout the battery cell during both cooling and heating of the battery, thereby improving the performance and reliability of the battery system. Brief explanation of the drawing

[0019] FIGS. 1 and 2 are perspective views of a snake-type tube-type battery thermal management device according to an embodiment of the present invention, and FIG. 3 is a drawing showing battery cells arranged in the snake-shaped tube-type battery thermal management device of FIG. 1, and FIG. 4 is a drawing for explaining the structure of one side of a cooling tube of a snake-type tube battery thermal management device of FIG. 1 and FIG. 2, and FIG. 5 is a drawing for explaining the cooling water flow path of the cooling tube of the snake-type tube battery thermal management device of FIG. 1 and FIG. 2, and FIG. 6 is a drawing for explaining battery cooling of a snake-type tube-type battery thermal management device according to one embodiment of the present invention, and FIG. 7 is a drawing for explaining battery preconditioning of a snake-type tube-type battery thermal management device according to one embodiment of the present invention, and FIG. 8 is a drawing for explaining a snake-type tube-type battery thermal management device according to another embodiment of the present invention. Specific details for implementing the invention

[0020] Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. It should be noted that in assigning reference numerals to the components of each drawing, the same components are given the same reference numeral whenever possible, even if they are shown in different drawings.

[0021] Furthermore, in describing embodiments of the present invention, if it is determined that a detailed description of related known configurations or functions would hinder understanding of the embodiments of the present invention, such detailed description is omitted.

[0022] In addition, terms such as first, second, A, B, (a), (b), etc. may be used when describing the components of the embodiments of the present invention. These terms are used merely to distinguish the components from other components, and the essence, order, or sequence of the components is not limited by the terms.

[0024] Hereinafter, a snake-type tube-type battery thermal management device according to one embodiment of the present invention will be described in detail with reference to the drawings.

[0025] FIGS. 1 and 2 are perspective views of a snake-type tube-type battery thermal management device according to one embodiment of the present invention, FIG. 3 is a drawing showing a battery cell arranged in the snake-type tube-type battery thermal management device of FIG. 1, FIG. 4 is a drawing for explaining the structure of one side of a cooling tube of the snake-type tube-type battery thermal management device of FIGS. 1 and 2, FIG. 5 is a drawing for explaining the cooling water flow path of the cooling tube of the snake-type tube-type battery thermal management device of FIGS. 1 and 2, FIG. 6 is a drawing for explaining battery cooling of the snake-type tube-type battery thermal management device according to one embodiment of the present invention, FIG. 7 is a drawing for explaining battery preconditioning of the snake-type tube-type battery thermal management device according to one embodiment of the present invention, and FIG. 8 is a drawing for explaining a snake-type tube-type battery thermal management device according to another embodiment of the present invention.

[0027] Referring to FIGS. 1 to 8, a snake-type tube-type battery thermal management device (100) according to one embodiment of the present invention includes a cooling tube (110), a first manifold (120), and a second manifold (130).

[0028] The cooling tube (110) is formed in a wave shape to contact the sides of a plurality of battery cells (10).

[0029] The above cooling tube (110) can be manufactured through an aluminum extrusion process. Specifically, after heating an aluminum billet, a tube-shaped extruded material is formed by extruding it through an extrusion die having a flat oval cross section shape, thereby forming a cooling water channel (110f) formed inside. Afterward, the extruded material is cut to a predetermined length and then formed into a snake shape through a bending process to form a wave shape along the arrangement of each battery cell (10).

[0030] The above cooling tube (110) may also be manufactured through a hydroforming process. Specifically, by placing a metal tube inside a mold and applying fluid pressure inside to expand the metal tube, it is formed to have a flat oval cross section shape and an outer shape corresponding to the outer curvature of the battery cell (10).

[0031] Here, a flat oval cross-section refers to an elliptical cross-section in which at least a portion of the outer surface is formed flat so as to enable surface contact with the side of the battery cell (10).

[0032] Each of the above battery cells (10) refers to a cylindrical battery cell (10).

[0033] For example, it may be a large-diameter cylindrical battery cell (10) with a diameter of about 18 millimeters or 21 millimeters.

[0034] The side of each battery cell (10) can be in surface contact with the cooling tube (110).

[0035] Specifically, the cooling tube (110) is formed with at least a portion of its outer surface in a curved shape to correspond to the outer curvature of the cylindrical battery cell (10), and is configured to enable surface contact with the side of the battery cell (10) through the curved shape.

[0036] Accordingly, as the surface contact area between the cooling tube (110) and the battery cell (10) increases, the thermal resistance is reduced compared to local contact, and the heat of the battery cell (10) can be dispersed and released more efficiently.

[0037] Meanwhile, the cooling water passage (110f) of the cooling tube (110) may be eccentrically positioned toward the outer surface that contacts the battery cell (10), spaced apart from the geometric center of the flat oval cross-section. Accordingly, the heat transfer path between the cooling water passage (110f) of the cooling tube (110) and the battery cell (10) is shortened, thereby improving cooling responsiveness.

[0038] In addition, the thickness of the tube on the side in contact with the battery cell (10) can be formed relatively thin due to the eccentric arrangement of the cooling water flow path (110f) of the cooling tube (110).

[0039] Specifically, the cooling tube (110) may include a first surface (110a) in contact with the battery cell (10) and a second surface (110b) spaced apart from the first surface (110a) to form a cooling water channel (110f). In this case, the thickness of the first surface (110a) is formed to be thinner than the thickness of the second surface (110b), thereby further improving the heat transfer efficiency in the contact area with the battery cell (10).

[0040] Meanwhile, the coolant passing through the coolant passage (110f) is not particularly limited as long as it is a fluid capable of absorbing or transferring heat generated from the battery cell (10).

[0041] However, the coolant of the present invention may be a water-based coolant having high specific heat and thermal conductivity.

[0042] In addition, the cooling water of the present invention may be a mixed fluid containing glycol-based components to prevent freezing in low-temperature environments and to ensure stable circulation in high-temperature environments.

[0043] For example, the coolant of the present invention may be a mixture of water and ethylene glycol or propylene glycol, and such glycol-based mixed coolant has a relatively stable viscosity so that it can circulate smoothly without a sudden increase in flow resistance inside the snake-shaped cooling tube (110).

[0044] Specifically, the coolant may contain 55 volume percent (vol%) to 75 vol% of water and 25 vol% to 45 vol% of a glycol-based component based on the total coolant. In this range, heat generated from the battery cell (10) can be effectively absorbed due to the high specific heat and thermal conductivity of the water, and the glycol-based component ensures prevention of freezing in low-temperature environments and circulation stability in high-temperature environments.

[0045] In addition, the glycol component may be a mixture of ethylene glycol and propylene glycol, and it is preferable to set 60 to 85 parts by weight of ethylene glycol and 15 to 40 parts by weight of propylene glycol based on 100 parts by weight of the glycol component.

[0046] This mixing ratio ensures excellent heat transfer characteristics and antifreeze performance through ethylene glycol, while simultaneously mitigating the increase in viscosity through propylene glycol and suppressing the increase in flow resistance in snake-shaped bending channels.

[0047] In particular, since the snake-shaped cooling tube (110) of the present invention includes a plurality of curvature changes, it is desirable that the cooling water has rheological characteristics that allow laminar and turbulent flow to be stably maintained even in the curved section.

[0048] Accordingly, water or a mixture of water and glycol coolant suppresses the occurrence of localized stagnation areas in bend sections and enables uniform heat exchange throughout the entire length of the cooling tube.

[0049] An insulating coating layer (111) is formed on the outer surface of the cooling tube (110) to prevent an electrical short circuit caused by direct contact with the battery cell (10).

[0050] The cooling tube (110) is configured to be electrically insulated from the battery cell (10) by the insulating coating layer (111) above.

[0051] The above insulating coating layer (111) may be an anodized layer.

[0052] Additionally, the insulating coating layer (111) may be formed from a ceramic material, a silicone material, an epoxy resin, a polyimide resin, or a resin material including a ceramic filler such as alumina, boron nitride, or aluminum nitride.

[0053] The above snake-shaped tube-type battery thermal management device (100) may further include a heat transfer pad (112).

[0054] The heat transfer pad (112) is formed on the outer surface of the insulating coating layer (111) so as to be located between each battery cell (10) and the insulating coating layer (111).

[0055] The heat transfer pad (112) is configured to improve heat transfer between the battery cell (10) and the cooling tube (110) and to absorb play caused by vibration.

[0056] For example, the heat transfer pad (112) is formed from a material having electrical insulation properties while possessing thermal conductivity and elasticity. Specifically, the heat transfer pad (112) may be formed from an elastic resin material such as a silicone-based material, a thermally conductive elastomer, or a urethane-based material.

[0057] Referring again to FIGS. 6 and FIGS. 7, the first manifold (120) is provided on one side of the cooling tube (110), and the cooling water may be introduced into the cooling tube (110) through the first manifold (120) or the cooling water of the cooling tube (110) may be discharged through the first manifold (120).

[0058] And the second manifold (130) is provided on the other side of the cooling tube (110), and the cooling water of the cooling tube (110) may be discharged through the second manifold (130), or the cooling water may be introduced into the cooling tube (110) through the second manifold (130).

[0059] However, the first manifold (120) and the second manifold (130) are not limited to being provided on each side of the cooling tube (110), and the first manifold (120) and the second manifold (130) may be provided in an up-and-down direction on one side of the cooling tube (110) (see FIG. 8).

[0060] Specifically, the first manifold (120) is provided on the upper side of one side of the cooling tube (110), and cooling water flows into the cooling tube (110) through the first manifold (120). The second manifold (130) is provided on the lower side of the other side of the cooling tube (110), and cooling water from the cooling tube (110) flows out through the second manifold (130).

[0061] When battery cooling is required, for example, during battery use such as driving a vehicle, the heat generated in each battery cell (10) tends to concentrate upward along the height direction of the cell, so a temperature difference between the upper and lower parts of the battery pack may occur. This temperature difference between the upper and lower parts of the battery pack causes uneven cell degradation and is a factor that reduces battery life.

[0062] In the present invention, by placing the cooling water cooler (21) on the side of the first manifold (120), the cooling water with a relatively low temperature can be configured to be supplied first to the upper side of the cooling tube (110).

[0063] Accordingly, heat generated in the upper region of the battery cell (10) can be effectively absorbed, and as the coolant flows along the snake-shaped cooling tube (110) toward the second manifold (130), uniform heat exchange can be achieved throughout the height direction of the battery cell (10). As a result, the temperature difference between the upper and lower parts of the battery cell (10) is reduced when the battery is in use, thereby improving cooling efficiency.

[0064] Meanwhile, if heating is required for the battery, a heater (22) may be included to perform a pre-conditioning function, for example, before charging the battery or for use in a low-temperature environment.

[0065] The heater (22) is positioned on the cooling water circulation path so that it can heat the cooling water and then supply it to the cooling tube (110) through the second manifold (130).

[0066] Accordingly, the heated coolant flows into the cooling tube (110) from the lower side of the second manifold (130) and flows toward the first manifold (120) along a snake shape, and is delivered along the height direction of each battery cell (10). As a result, heat is transferred from the lower side to the upper side of the battery cell (10), making it possible to heat uniformly throughout the battery cell (10).

[0067] Accordingly, by preheating the battery cell (10) to an appropriate temperature during battery charging or in a low-temperature environment, the increase in internal resistance can be suppressed, and charging efficiency and output characteristics can be improved. In addition, the temperature difference between the upper and lower parts of the battery cell (10) can be mitigated by the circulation of a heating fluid through the snake-shaped cooling tube (110).

[0069] Although all components constituting an embodiment of the present invention have been described above as being combined or operating in combination, the present invention is not necessarily limited to such embodiments. That is, within the scope of the purpose of the present invention, all components may be selectively combined in one or more ways to operate.

[0070] Furthermore, all terms, including technical or scientific terms described above, have the same meaning as generally understood by those skilled in the art to which the present invention pertains, unless otherwise defined. Commonly used terms, such as those defined in advance, should be interpreted as consistent with their meaning in the context of the relevant technology and should not be interpreted in an ideal or overly formal sense unless explicitly defined in the present invention.

[0071] Furthermore, the foregoing description is merely an illustrative explanation of the technical concept of the present invention, and those skilled in the art to which the present invention pertains will be able to make various modifications and variations within the scope of the essential characteristics of the present invention. Accordingly, the embodiments disclosed in the present invention are intended to explain, not limit, the technical concept of the present invention, and the scope of the technical concept of the present invention is not limited by such embodiments. The scope of protection of the present invention shall be interpreted by the claims below, and all technical concepts within an equivalent scope shall be interpreted as being included within the scope of rights of the present invention. Explanation of the symbols

[0072] 100: Snake-shaped tube-type battery thermal management device 110: Cooling tube 110a: 1st side 110b: 2nd side 110f: Coolant flow path 120: 1st manifold 130: 2nd manifold

Claims

Claim 1 A cooling tube formed in a wave shape to contact the sides of a plurality of battery cells, a first manifold provided on one side of the cooling tube for introducing cooling water into the cooling tube, and a second manifold provided on the other side of the cooling tube for discharging cooling water from the cooling tube, wherein the cooling tube has a flat oval cross-sectional shape and a cooling water passage formed inside, and includes a first surface that contacts the battery cell and a second surface that is spaced apart from the first surface and forms the cooling water passage, wherein the cooling water passage is eccentrically arranged toward the first surface side that contacts the battery cell, spaced apart from the geometric center of the flat oval cross-section, and the tube thickness on the first surface side is formed to be thinner than the tube thickness on the second surface side, and an insulating coating layer for electrical insulation with respect to the battery cell is formed on the surface of the cooling tube, and a heat transfer pad formed of a material having electrical insulation properties, thermal conductivity, and elasticity is located between the battery cell and the insulating coating layer, and the cooling water comprises water and a glycol-based component, and A snake-shaped tube-type battery thermal management device characterized by the glycol component comprising 60 to 85 parts by weight of ethylene glycol and 15 to 40 parts by weight of propylene glycol. Claim 2 A snake-type tube-type battery thermal management device according to claim 1, characterized in that the side of each battery cell is in surface contact with the cooling tube. Claim 3 delete Claim 4 delete Claim 5 delete

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