Immersed cooling device for columnar lithium ion battery pack

Abstract

The invention discloses an immersed cooling device for a columnar lithium ion battery pack, relates to the technical field of battery heat exchange, and solves the problems that a battery cooling device is greatly influenced by the environment, large in size, low in heat exchange efficiency, non-uniform in battery cooling and high in cost. Baffle plates are symmetrically arranged on the two sides of a middle baffle. One part of the baffle plate is connected with the upper end cover, and the other part of the baffle plate is connected with the lower end cover; the left baffle plate is connected with the left ends of the uppermost baffle plate and the lowermost baffle plate, and the right baffle plate is connected with the right ends of the uppermost baffle plate and the lowermost baffle plate; the middle baffle divides the interior of the right baffle into two parts and is provided with a liquid outlet and a liquid inlet; and a plurality of columnar batteries are arranged among the plurality of baffle plates, penetrate through the middle baffle plate and are connected with the upper end cover and the lower end cover. The battery main body is completely immersed in the cooling liquid, so that the heat exchange uniformity of the battery is improved, and local hot spots of the battery are reduced; the snake-shaped flow channel enables the flow speed of fluid to be increased at a bend under the action of centrifugal force, and the heat exchange effect is improved.

Description

Technical Field

[0001] The invention relates to the technical field of battery heat exchange, and in particular to an immersion cooling device for a columnar lithium-ion battery pack. Background Art

[0002] As electric vehicles become more and more popular in the market, they are gradually entering thousands of households. Electric vehicle battery cooling devices are devices that reduce the temperature of vehicle batteries. When electric vehicles are working, the battery will generate a certain amount of heat. If the battery heat is not dissipated in time, the battery will be seriously affected in a high temperature environment, such as shortening the battery life, affecting battery charging and endurance, etc. Therefore, some measures must be taken to cool the battery to ensure its normal working temperature.

[0003] Air cooling (wind cooling), indirect liquid cooling, and phase change material (PCM) cooling are the three mainstream cooling methods on the market. The cooling efficiency of air-cooled batteries is low, and the cooling effect is greatly affected by the environment. In a high humidity environment, dew will appear on the surface of the battery, which will eventually lead to battery failure; in a high temperature environment, the cooling effect of the battery is not good. The cooling efficiency of indirect liquid cooling will be affected by the cold plate material and its thermal conductivity. Because the cold plate is in direct contact with the battery, this will increase the volume of the battery pack, increase the space for placing the battery, and increase the cost. In phase change material cooling technology, phase change materials can absorb the heat released by the battery, but the maximum temperature during battery operation depends to a large extent on the phase change temperature and thermal conductivity of the PCM, but the thermal conductivity of the PCM is often very low, which limits the use of phase change material cooling.

[0004] The Chinese patent with publication number CN112490537A discloses "Immersed Cooling Mechanism of Lithium Ion Battery and Lithium Ion Battery Module", which is a closed container and a cooling circulation device composed of multiple wall panels. The closed container has a cooling cavity filled with cooling medium, and the cavity has a mounting position for fixing the lithium ion battery. The lithium ion battery is fixed on the mounting position, and the battery body is wrapped with cooling medium, and the circulating cooling medium is used to cool the lithium ion battery. Compared with the prior art, this device can reduce the use of cooling medium and extend the service life of the cooling medium. However, in this device, all lithium ion batteries are immersed in the cooling medium. If the battery body leaks and the cooling medium conducts electricity, it may cause corrosion, short circuit and other safety problems. In addition, the device is not very closed, and the sealing of the cooling medium is not well demonstrated. If the cooling medium leaks, the maintenance cost of the device will be greatly increased. The Chinese patent with publication number CN117996273A discloses an "Immersed Cooling Battery Box", in which the battery assembly is installed in a accommodating cavity inside the box, and a flow channel for the cooling medium is provided between every two adjacent batteries. There are also flow channels on the sides, top, and bottom. The liquid inlet is connected to the side flow channel, and the liquid outlet is connected to the top flow channel and the bottom flow channel. The cooling is performed by the flow of the cooling medium in the flow channel. Because this device cools the battery by establishing a flow channel on the battery, the uniformity of the battery heat dissipation is not very good, and the local battery temperature will be higher than the battery temperature at the flow channel, and the heat dissipation effect is not very ideal. In summary, how to design a battery heat dissipation device with good airtightness so that the battery body can be cooled evenly is the key issue currently concerned. Summary of the invention

[0005] In order to solve the above-mentioned problems of existing battery cooling devices being greatly affected by the environment, having a large structure volume, low heat exchange efficiency, uneven battery cooling, and high manufacturing and installation costs, the present invention proposes an immersion cooling device for a columnar lithium-ion battery pack. The present invention completely immerses the battery body in the coolant, thereby improving the uniformity of battery heat exchange and reducing the occurrence of local hot spots in the battery; the flow channel is designed to be serpentine through a number of baffles, and the fluid is subjected to centrifugal force at the bend to increase the flow velocity, thereby improving the heat exchange effect.

[0006] The present invention provides an immersion cooling device for a columnar lithium-ion battery pack, which specifically includes an upper end cover, a lower end cover, a plurality of baffle plates, a middle baffle, a left baffle and a right baffle; the plurality of baffle plates are divided into two parts and symmetrically arranged on both surfaces of the middle baffle; one part of the baffle plates is connected to the upper end cover, and the other part of the baffle plates is connected to the lower end cover; a left baffle and a right baffle are arranged between the upper end cover and the lower end cover; the left baffle and the right baffle are respectively arranged on the left side and the right side of the middle baffle; the left baffle is connected to the left ends of the uppermost and lowermost baffle plates among the plurality of baffle plates, and the right baffle is connected to the right ends of the uppermost and lowermost baffle plates among the plurality of baffle plates; the middle baffle divides the interior of the right baffle into two parts, and a liquid outlet and a liquid inlet are respectively opened on the two parts; a plurality of columnar batteries are arranged between the plurality of baffle plates, and the columnar batteries pass through the middle baffle and are respectively connected to the upper end cover and the lower end cover.

[0007] Furthermore, the left baffle and the right baffle are in a C-shaped structure.

[0008] Furthermore, the liquid outlet and the liquid inlet are arranged at the diagonal positions at both ends of the right baffle.

[0009] Furthermore, a plurality of through holes are provided on the upper end cover and the lower end cover, and the tabs of the columnar battery pass through the through holes.

[0010] Furthermore, the baffle plate is in a serpentine structure.

[0011] Furthermore, the columnar battery is arranged on the inner concave side of the arc of the serpentine structure of the baffle plate.

[0012] Furthermore, clamping grooves are provided on the upper end cover and the lower end cover, and the ends of the columnar battery are connected to the clamping grooves.

[0013] Furthermore, a sealing ring is arranged between the clamping groove and the columnar battery.

[0014] Furthermore, a plurality of mounting holes are provided on the middle baffle, and the columnar battery passes through the mounting holes; a sealing ring is arranged between the columnar battery and the mounting holes.

[0015] The beneficial effects of the immersion cooling device for a columnar lithium-ion battery pack according to the present invention are as follows:

[0016] (1) The immersion cooling device for a columnar lithium-ion battery pack according to the present invention overcomes the problems of large influence of the existing battery cooling device by the environment, large structural volume, low heat exchange efficiency, uneven battery temperature reduction, and high manufacturing and installation costs. By immersing the columnar battery body with the coolant, a more uniform heat distribution is achieved, and the occurrence of local hot spots is reduced; the tabs at both ends of the battery pass through the through holes provided on the upper end cover and the lower end cover, which not only helps to prevent the battery from leaking and polluting the coolant, but also facilitates wiring.

[0017] (2) In the immersion cooling device for a columnar lithium-ion battery pack described in the present invention, the baffle is a serpentine structure, and a plurality of parallel baffles form a serpentine flow channel. The coolant is subjected to the centrifugal force at the bend, thereby increasing the flow rate and impacting the battery at a greater flow rate, further enhancing heat transfer and making the battery cooling effect more obvious;

[0018] (3) The immersion cooling device for a columnar lithium-ion battery pack described in the present invention is conducive to balancing the pressure by placing the liquid inlet and the liquid outlet at the diagonal positions of the right baffle, and more effectively avoiding the problem of uneven heat dissipation of the battery caused by the coolant flowing into the cooling device. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0020] In the attached picture:

[0021] Figure 1 It is a three-dimensional structural schematic diagram of a columnar lithium-ion battery pack immersion cooling device according to the present invention;

[0022] Figure 2 It is a bottom view of an immersion cooling device for a columnar lithium-ion battery pack according to the present invention;

[0023] Figure 3 It is a structural schematic diagram of an upper end cover, a baffle, a left baffle and a right baffle of an immersion cooling device for a columnar lithium-ion battery pack according to the present invention;

[0024] Figure 4 It is a structural schematic diagram of a lower end cover and a baffle of an immersion cooling device for a columnar lithium-ion battery pack according to the present invention;

[0025] Figure 5 It is a structural schematic diagram of a middle baffle of a columnar lithium-ion battery pack immersion cooling device according to the present invention;

[0026] Figure 6 It is a structural schematic diagram of a card slot of a columnar lithium-ion battery pack immersion cooling device according to the present invention;

[0027] Figure 7 It is a structural schematic diagram of a sealing ring of a columnar lithium-ion battery pack immersion cooling device according to the present invention;

[0028] Among them: 1-upper end cover, 2-lower end cover, 3-ear, 4-baffle, 5-liquid outlet, 6-middle baffle, 7-liquid inlet, 8-left baffle, 9-right baffle, 10-sealing ring, 11-flow channel outlet. DETAILED DESCRIPTION

[0029] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0031] In the description of the invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the invention can be understood according to specific circumstances.

[0032] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0033] Specific implementation method 1: See Figure 1-Figure 7 The present embodiment is described in detail. The immersion cooling device for a columnar lithium-ion battery pack described in the present embodiment specifically comprises an upper end cover 1, a lower end cover 2, a plurality of baffles 4, an intermediate baffle 6, a left baffle 8 and a right baffle 9; the plurality of baffles 4 are divided into two parts and symmetrically arranged on the two side surfaces of the intermediate baffle 6, and the plurality of baffles 4 are parallel to each other; a part of the baffles 4 is connected to the upper end cover 1, and the other part of the baffles 4 is connected to the lower end cover 2; a left baffle 8 and a right baffle 9 are arranged between the upper end cover 1 and the lower end cover 2; the left baffle 8 and the right baffle 9 are respectively arranged on the left and right sides of the intermediate baffle 6; the left baffle 8 is connected to the left end of the uppermost and lowermost baffles 4 among the plurality of baffles 4, and the right baffle 9 is connected to the right end of the uppermost and lowermost baffles 4 among the plurality of baffles 4, as shown in FIG. Figure 1-Figure 3As shown in the figure; the middle baffle 6 divides the interior of the right baffle 9 into two parts, and a liquid outlet 5 and a liquid inlet 7 are respectively provided on the two parts; a number of columnar batteries are arranged between several baffle plates 4, and the columnar batteries pass through the middle baffle 6 and are respectively connected to the upper end cover 1 and the lower end cover 2.

[0034] The left baffle 8 and the right baffle 9 are in a C-shaped structure, and the open sides of the C-shaped structures of the left baffle 8 and the right baffle 9 face each other; the open sides of the C-shaped structure of the left baffle 8 are respectively connected to the left ends of the uppermost and lowermost baffle plates 4 among several baffle plates 4, and the open sides of the C-shaped structure of the right baffle 9 are respectively connected to the right ends of the uppermost and lowermost baffle plates 4 among several baffle plates 4, cooperating with the upper end cover 1 and the lower end cover 2 to form the cavity of the cooling device; the middle baffle 6 divides the entire cavity into upper and lower parts, extending the flow path of the coolant.

[0035] The liquid outlet 5 and the liquid inlet 7 are arranged at the diagonal positions at both ends of the right baffle 9, the liquid inlet 7 is close to the lower end cover 2, and the liquid outlet 5 is close to the upper end cover 1, which is beneficial to balancing the pressure.

[0036] A number of through holes are provided on the upper end cover 1 and the lower end cover 2, and the tabs 3 of the columnar battery pass through the through holes to prevent the battery from leaking and polluting the coolant.

[0037] The baffle plate 4 is in a serpentine structure, and two adjacent baffle plates 4 form a serpentine flow path. The columnar battery is arranged on the inner concave side of the arc of the serpentine structure of the baffle plate 4.

[0038] Slots are provided on the upper end cover 1 and the lower end cover 2, and the ends of the columnar battery are connected to the slots, thereby fixing the position of the battery; the diameter of the slots is slightly larger than the diameter of the battery. A sealing ring 10 is provided between the slots and the columnar battery.

[0039] A number of mounting holes are provided on the middle baffle 6, and the columnar battery passes through the mounting holes; a sealing ring 10 is provided between the columnar battery and the mounting holes.

[0040] The specific working principle of the immersion cooling device for a columnar lithium-ion battery pack according to the present invention is as follows:

[0041] The coolant enters the immersion cooling device from the liquid inlet 7, and flows into the top of the lower end cover 2 through the flow channel 11 between the baffles 4. Since the baffles 4 are laid on the lower end cover 2 in the form of a serpentine plate, the coolant will generate a greater flow rate under the action of centrifugal force to impact the battery body when flowing between the serpentine baffles 4, which can better help the battery dissipate heat. When the coolant level slowly rises and hits the middle baffle 6, since the middle baffle 6 is closely connected to the right baffle 9 and there is a certain gap between the middle baffle 6 and the left baffle 8, the coolant will only slowly flow into the top from the gap on the left. As the coolant slowly flows in, the liquid level continues to rise and fills the entire immersion cooling device. The heat generated by the battery during operation is transferred to the coolant in the form of heat transfer. When the liquid rises to hit the liquid outlet 5, the coolant will eventually be discharged from the liquid outlet 5 to enter the external circulation system for recirculation, significantly improving the heat dissipation efficiency.

[0042] Summarizing the above implementation cases, the immersion cooling device for a columnar lithium-ion battery pack described in the present invention overcomes the problems of existing battery cooling devices being greatly affected by the environment, having a large structure volume, low heat exchange efficiency, uneven battery cooling, and high manufacturing and installation costs. By immersing the columnar battery body in the coolant, a more uniform heat distribution is achieved, and the occurrence of local hot spots is reduced; the pole ears 3 at both ends of the battery pass through the through holes set on the upper end cover 1 and the lower end cover 2, which is not only conducive to preventing the battery from leaking and contaminating the coolant, but also convenient for wiring; the immersion cooling device for a columnar lithium-ion battery pack described in the present invention, the baffle 4 is a serpentine structure, and a plurality of parallel baffles 4 form a serpentine flow channel. The coolant is subjected to the centrifugal force at the bend, thereby increasing the flow rate, impacting the battery with a greater flow rate, further strengthening the heat transfer, and making the battery cooling effect more obvious; the immersion cooling device for a columnar lithium-ion battery pack described in the present invention, by placing the liquid inlet 7 and the liquid outlet 5 at the diagonal position of the right baffle 9, is conducive to balancing the pressure, and more effectively avoiding the problem of uneven heat dissipation of the battery caused by the coolant flowing into the cooling device.

[0043] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the invention. It can also be a reasonable combination of the features recorded in the above implementation methods. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. An immersion cooling device for a columnar lithium-ion battery pack, characterized in that: It includes an upper end cover (1), a lower end cover (2), several baffle plates (4), an intermediate baffle (6), a left baffle (8) and a right baffle (9); the several baffle plates (4) are divided into two parts and symmetrically arranged on both side surfaces of the intermediate baffle (6); one part of the baffle plates (4) is connected to the upper end cover (1), and the other part of the baffle plates (4) is connected to the lower end cover (2); a left baffle (8) and a right baffle (9) are arranged between the upper end cover (1) and the lower end cover (2); the left baffle (8) and the right baffle (9) are respectively arranged on the left side and the right side of the intermediate baffle (6); the left baffle (8) is connected to the left ends of the uppermost and lowermost baffle plates (4) among the several baffle plates (4), and the right baffle (9) is connected to the right ends of the uppermost and lowermost baffle plates (4) among the several baffle plates (4); the intermediate baffle (6) divides the interior of the right baffle (9) into two parts, and a liquid outlet (5) and a liquid inlet (7) are respectively formed on the two parts; several columnar batteries are arranged between the several baffle plates (4), and the columnar batteries pass through the intermediate baffle (6) and are respectively connected to the upper end cover (1) and the lower end cover (2).

2. The immersion cooling device for a columnar lithium-ion battery pack according to claim 1, characterized in that: The left baffle (8) and the right baffle (9) are in a C-shaped structure.

3. The immersion cooling device for a columnar lithium-ion battery pack according to claim 2, characterized in that: The liquid outlet (5) and the liquid inlet (7) are arranged at the diagonal positions at both ends of the right baffle (9).

4. The immersion cooling device for a columnar lithium-ion battery pack according to claim 1, characterized in that: Several through holes are provided on the upper end cover (1) and the lower end cover (2), and the tabs (3) of the columnar batteries pass through the through holes.

5. The immersion cooling device for a columnar lithium-ion battery pack according to claim 1, characterized in that: The baffle plate (4) is in a serpentine structure.

6. The immersion cooling device for a columnar lithium-ion battery pack according to claim 5, characterized in that: The columnar batteries are arranged on the inner concave side of the arc of the serpentine structure of the baffle plate (4).

7. The immersion cooling device for a columnar lithium-ion battery pack according to claim 1, characterized in that: Slots are provided on the upper end cover (1) and the lower end cover (2), and the ends of the columnar batteries are connected to the slots.

8. The immersion cooling device for a columnar lithium-ion battery pack according to claim 7, characterized in that: A sealing ring (10) is arranged between the slots and the columnar batteries.

9. The immersion cooling device for a columnar lithium-ion battery pack according to claim 1, characterized in that: Several mounting holes are provided on the intermediate baffle (6), and the columnar batteries pass through the mounting holes; a sealing ring (10) is arranged between the columnar batteries and the mounting holes.

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