Battery modules, battery packs, electric vehicles and power grid systems

Abstract

The present invention provides a battery module, including a shell, a battery cell, a heat spreader and a heat dissipation device. The shell includes panels in six directions: up, down, front, back, left and right. A plurality of battery cells are arranged in the shell. The heat spreader is installed in the shell and clamped between the battery cells, and the heat spreader is filled with a heat transfer medium. The heat dissipation device includes the functions of heat distribution, heat exchange and heat dissipation. The present invention also provides a battery pack, an electric vehicle and a power grid system having the battery module. The heat spreader filled with a heat transfer medium can quickly absorb the heat generated during the charging and discharging process of the battery cell, and spread the heat evenly to transfer it to the heat dissipation device, so that the internal heat of the battery module can be quickly dissipated. Therefore, it can prevent the battery pack, the electric vehicle and the power grid system from being affected in normal use or causing safety accidents due to insufficient heat dissipation of the battery module.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to a battery module, a battery pack, an electric vehicle and a power grid system. Background Art

[0002] During the charging and discharging process of the battery pack, a large amount of heat will accumulate inside the battery. If the heat is not discharged in time, the battery temperature will be too high or the temperature uniformity will be poor, which will not only affect the battery capacity and service life, but also cause thermal runaway in severe cases, resulting in the battery breaking, smoking, and even causing the battery to explode. On the contrary, if the battery pack is in a low temperature environment, the life will be shortened, the charging and discharging capacity will drop sharply, and the battery utilization efficiency will be low. Therefore, it is particularly important to control the heat and temperature of the battery.

[0003] At present, the following methods are generally adopted for heat exchange of battery packs: (1) natural convection heat dissipation. The battery pack has a large space and good contact with the air. The exposed part can exchange heat with the air naturally. However, this method of heat dissipation is very slow and can easily cause thermal runaway. (2) air-cooled structure heat dissipation. A cooling fan is installed at one end of the battery pack, and ventilation holes are left at the other end to accelerate the flow of air between the battery cells and take away the heat during operation. Compared with natural convection heat dissipation, the heat dissipation speed is increased, but there are still problems such as poor heat uniformity and ineffective heat dissipation when a large amount of heat is accumulated. It is also easy to cause thermal runaway. (3) liquid-cooled structure heat dissipation. The heat of the battery cell is transferred to the liquid cooling pipe through the thermal conductive silicone sheet, and the heat is taken away by the free circulation of the coolant due to thermal expansion and contraction. However, it adopts a closed free liquid cooling cycle (passive liquid cooling). Although the coolant has a large specific heat capacity and can absorb a large amount of heat, the cooling effect is much better than the previous two methods, but the system coolant is limited, the flow rate is also limited, the heat uniformity effect is not good, and therefore the temperature control ability is limited. Summary of the invention

[0004] In view of the shortcomings of the prior art described above, the purpose of the present invention is to provide a battery module, a battery pack, an electric vehicle and a power grid system to solve the problems existing in the prior art of low heat transfer efficiency, easy thermal runaway, and the inability of batteries to charge and discharge in extremely cold areas.

[0005] To achieve the above-mentioned and other related purposes, the present invention provides a battery module, comprising:

[0006] The outer shell includes six panels arranged opposite to each other up, down, front, back, left and right;

[0007] A battery cell, in a rectangular shape, is disposed in the housing, mounted on the bottom panel and extending toward the top panel;

[0008] A heat spreader is installed in the housing and sandwiched between the battery cells. At least one battery cell is sandwiched between two adjacent heat spreaders. The heat spreader is filled with a heat transfer medium.

[0009] The heat dissipation device is installed in the shell and placed on the top or bottom of the battery and the heat spreader to perform heat distribution, heat exchange and heat dissipation. The heat dissipation device includes a thermal superconducting tube line filled with a heat transfer medium. The heat dissipation device also includes a refrigerant channel or a fin.

[0010] Preferably, the upper end or the lower end or both ends of the heat spreader have right-angled edges to increase the contact area with the flexible insulating thermal conductive sheet while stabilizing and protecting the battery core.

[0011] Preferably, the two polarity terminals of the battery cell are respectively on two opposite sides of the battery cell.

[0012] Preferably, a flexible insulating heat-conducting sheet is sandwiched between the heat spreader and the battery cell, and between the heat spreader, the battery cell and the heat dissipation device.

[0013] Preferably, the heat dissipation device has a thermal superconducting tube line, and the thermal superconducting tube line is filled with a heat transfer medium.

[0014] Preferably, the heat dissipation device has a refrigerant channel, the refrigerant channel surrounds the thermal superconducting pipe, both ends of the refrigerant channel are not closed on the heat dissipation device, the refrigerant enters from the refrigerant channel inlet, absorbs heat or releases heat and flows out from the refrigerant channel outlet.

[0015] Preferably, the heat sink has fins, which are arranged at a certain angle θ and connected to the heat sink, wherein 0°<θ<180°.

[0016] The present invention further provides a battery pack, comprising at least two battery modules stacked or arranged side by side.

[0017] The present invention also provides an electric vehicle, comprising the battery pack.

[0018] The present invention further proposes a power grid system, comprising the battery pack, wherein the power grid system is a smart grid system, a wind power system or a solar power system.

[0019] The technical solution of the present invention provides a battery module, including a shell, a battery cell, a heat spreader and a heat sink. The battery cell, the heat spreader and the heat sink are all placed in the shell. The heat spreader is a plate filled with a heat transfer medium, which has the characteristics of fast heat transfer rate and good temperature uniformity. It can quickly absorb the heat generated during the charging and discharging process of the battery cell, and spread the heat to the heat sink to quickly dissipate the heat inside the battery module. The heat sink is provided with a refrigerant channel or fins, which can quickly take away the heat, thereby preventing the battery pack, electric vehicle and power grid system from being affected in normal use or causing safety accidents due to insufficient heat dissipation of the battery module. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Shown is a schematic diagram of the external structure of a battery module according to an embodiment of the present invention.

[0021] Figure 2 Shown is a schematic diagram of a heat spreader in a battery module of the present invention.

[0022] Figure 3 Display as Figure 1 Schematic diagram of the heat sink.

[0023] Figure 4 Shown is a schematic diagram of the external structure of another embodiment of the battery module of the present invention.

[0024] Figure 5 Display as Figure 4 Schematic diagram of the heat sink.

[0025] Component number explanation: 1-battery module, 11-upper panel of the shell, 12-lower panel of the shell, 13-rear panel of the shell, 14-left panel of the shell, 15-right panel of the shell, 16-front panel of the shell, 17-insulating buffer pad, 2-battery cell, 21-first polarity terminal, 22-second polarity terminal, 3-flexible insulating thermal conductive sheet, 41-heat spreader, 411-thermal superconducting pipe, 412-upper folded edge, 413-lower folded edge, 42-heat dissipation plate, 421-refrigerant channel, 422-refrigerant inlet, 423-refrigerant outlet, 43-air cooling plate, 431-base plate, 432-fin, 433-fixing hole, 51-limiting row, 52-connector.

[0026] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0027] The following describes the embodiments of the present invention through specific examples. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. The details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0028] The present invention provides a battery module 1. Figure 1 and Figure 4 As shown, the battery module 1 includes a housing, a battery cell 2, a heat spreader 41 and a heat dissipation device.

[0029] The housing includes panels in six directions: up, down, front, back, left, and right. The upper housing 11 and the lower housing 12 are arranged opposite to each other, the left side 14 and the right side 15 are arranged opposite to each other, and the front side 16 and the rear side 13 are arranged opposite to each other. It can be understood that the housing and the insulating buffer pad 17 are used to protect the battery cell, the heat spreader, and the heat dissipation device.

[0030] A plurality of battery cells 2 are arranged in the housing, mounted on the housing lower panel 12, and extending toward the housing upper panel 11. The battery cells are in a rectangular shape, and the first polarity terminal 21 and the second polarity terminal 22 of the battery cells 2 face the housing left panel 14 and the housing right panel 15, respectively. The plurality of battery cells 2 are arranged in a certain series-parallel arrangement, and the limit row 51 is used to fix the positions of the plurality of battery cells 2. The polarity terminal 21 or 22 of the battery cell 2 passes through the gap in the middle of the limit row 51, and then the connector 52 connects the polarity terminals of two adjacent battery cells.

[0031] The heat spreader 41 is arranged in the shell, and the heat spreader 41 has a closed thermal superconducting tube 411, and the thermal superconducting tube 411 is filled with a heat transfer medium (not shown). It can be understood that the thermal superconducting tube can be a single-sided bulging, double-sided bulging or double-sided flat structure on the heat spreader. Among them, the filled heat transfer medium can be a gas or a liquid or a mixture of a gas and a liquid, such as water, oil and a refrigerant. The upper end or the lower end or the upper and lower ends of the heat spreader have a right-angled fold to increase the contact area between the heat spreader 41 and the flexible insulating thermal conductive sheet 3.

[0032] The heat dissipation device is installed in the shell and placed on the top or bottom of the battery core 2 and the heat spreader 41. The heat dissipation device has a thermal superconducting pipe 411 filled with a heat transfer medium; the heat dissipation device also includes a refrigerant channel 421 or fins 432 to accelerate heat dissipation.

[0033] The battery module provided by the technical solution of the present invention comprises a housing, a plurality of battery cells, a heat spreader and a heat sink. The battery cells, the heat spreader and the heat sink are placed in the housing. The heat spreader quickly absorbs the heat during the charging and discharging process of the battery cells, and evenly spreads the heat and quickly transfers it to the heat sink, so that the heat inside the battery module is quickly dissipated.

[0034] Please also read Figure 2, a thermal superconducting tube 411 is distributed inside the heat spreader 41, and the thermal superconducting tube 411 is used to fill the above-mentioned heat transfer medium. The thermal superconducting tube 411 is a single-sided expansion, double-sided expansion or double-sided flat structure on the heat spreader. Among them, the thermal superconducting tube 411 is a closed structure, and the shape of the closed thermal superconducting tube 411 can be a hexagonal honeycomb that is interconnected, or a quadrilateral, triangle, circle and Z-shape that are interconnected, or a parallel cross-section with a circular, elliptical or polygonal shape, or any combination of any two or more of these shapes. The upper and lower ends of the heat spreader have right-angled folds in the same direction, and the width of the fold is equivalent to the thickness of the battery cell.

[0035] In one embodiment of the present invention, see Figure 1 and Figure 3 As shown, a plurality of the battery cells 2 are arranged in a certain series-parallel arrangement in the housing, the battery cells are in a rectangular shape, and the two polarity terminals of the battery cells 2 are respectively on the left and right sides of the battery cells 2; the battery cells 2 are sandwiched between the heat spreaders 41, and at least one of the battery cells is sandwiched between the two adjacent heat spreaders; the heat spreader 2 has folded edges at both the upper and lower ends. Of course, in other embodiments, the folded edges can be at the upper end or the lower end of the heat spreader 41. The heat dissipation device is a heat sink 42, which is located on the upper part of the battery cells 2 and the heat spreader 41. Of course, in other embodiments, it can also be located at the bottom of the battery cells 2 and the heat spreader 41. A thermal superconducting pipe 411 and a refrigerant channel 421 are distributed inside the heat sink 42. Among them, the thermal superconducting pipe 411 is used to fill the above-mentioned heat transfer medium, and the refrigerant channel 421 is used to pass any one or more refrigerants such as water, oil and air. The thermal superconducting tube 411 and the refrigerant channel 421 are in a single-sided expansion, double-sided expansion or double-sided flat structure on the heat sink 42. Among them, the thermal superconducting tube 411 is a closed structure, and the shape of the closed thermal superconducting tube 411 can be interconnected hexagonal honeycomb, or interconnected quadrilateral, triangle, circle and Z-shape, or parallel to each other in the shape of circular, elliptical or polygonal cross-section, or any combination of any two or more of these shapes. Similarly, the cross section of the refrigerant channel 421 can also be a variety of shapes such as square, circular or diamond.

[0036] Furthermore, the refrigerant channel 421 surrounds the thermal superconducting pipe 411 in a "J" shape, and the two ends of the refrigerant channel 421 are connected. The refrigerant enters from the refrigerant inlet 422 of the refrigerant channel 421, and flows out from the refrigerant outlet 423 after absorbing or releasing heat. It should be noted that any one or more refrigerants such as water, oil and air can be introduced into the refrigerant channel 421. The heat sink filled with heat transfer medium has good thermal conductivity and temperature uniformity, and the function of the refrigerant channel 421 further improves the heat dissipation rate.

[0037] In another embodiment of the present invention, see Figure 4 and Figure 5 As shown, the heat dissipation device is an air-cooling plate 43 with fins, which is located on the upper part of the battery cell 2 and the heat spreader 41. Of course, in other embodiments, it can also be located at the bottom of the battery cell 2 and the heat spreader 41. The substrate 431 of the air-cooling plate 43 is filled with a heat transfer medium (not shown). Fixing holes 433 are respectively provided on the four corners of the substrate 431, and the fixing holes 433 are used to fix the air-cooling plate 43 to the entire battery module 1. The fins 432 are perpendicular to the substrate 431. Of course, in other embodiments, the fins 432 can be distributed on the substrate 432 at different angles. The fins 432 can be connected to the substrate by welding, aluminum extrusion, casting, machining, stamping, etc., so as to further dissipate the internal heat of the battery module 1.

[0038] The battery module 1 also includes a plurality of flexible insulating thermal conductive sheets 3, which are sandwiched between the heat spreader 41, the battery cell 2 and the heat sink. The flexible insulating thermal conductive sheet 3 is used to transfer the heat of the battery cell 2 to the heat spreader 41 and the heat sink. The thermal conductivity of the flexible insulating thermal conductive sheet is conducive to the heat spreader 41 absorbing the heat of the battery cell 2. At the same time, the flexibility and insulation of the flexible insulating thermal conductive sheet can protect the battery cell 2 from the collision and conductive interference of the heat spreader 41. Since thermally conductive silicone has good thermal conductivity and insulation properties, thermally conductive silicone is usually used as the main material of the flexible insulating thermal conductive sheet. Of course, the flexible insulating thermal conductive sheet can also be made of other flexible insulating thermal conductive materials or flexible phase change materials with insulation. It can be understood that the presence of the flexible insulating thermal conductive sheet reduces the probability of air heat transfer between the heat spreader 41 and the battery cell 2, and the heat sink and the heat spreader 41. Since the thermal resistance of air heat transfer is large, this may reduce the heat transfer efficiency of the entire battery module 1.

[0039] The present invention also provides a battery pack. The battery pack includes at least two battery modules 1 stacked or arranged side by side. Please refer to the above embodiment for the specific structure of the battery module 1. Since the battery pack adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here. It can be understood that in addition to the battery module, the battery pack also includes a control system and an electrical system.

[0040] The present invention also provides an electric vehicle. The electric vehicle includes the above-mentioned battery pack, and the battery pack includes the above-mentioned battery module 1. The specific structure of the battery module 1 is referred to the above-mentioned embodiment. Since the electric vehicle adopts all the technical solutions of all the above-mentioned embodiments, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here. It can be understood that the electric vehicle can be an electric car, an electric motorcycle or an electric balance car, etc.

[0041] The present invention also proposes a power grid system. The power grid system includes the above-mentioned battery module 1. The specific structure of the battery module 1 is referred to the above-mentioned embodiment. Since the power grid system adopts all the technical solutions of all the above-mentioned embodiments, it has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here. It can be understood that the power grid system can be a smart grid system, a wind power system or a solar power system, etc.

[0042] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the scope of the present invention. Anyone familiar with the technology may modify or change the above embodiments without violating the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention should still be covered by the rights and interests of the present invention.

Claims

1. A battery module, characterized in that: include: shell; A battery cell, disposed in the housing; A heat spreader is installed in the housing and sandwiched between the cells. The heat spreader has a thermal superconducting tube line filled with a heat transfer medium. A heat dissipation device is installed in the shell and is placed on the top or bottom of the battery core and the heat spreader; the heat dissipation device is filled with a heat transfer medium; the heat dissipation device has a thermal superconducting tube circuit, the thermal superconducting tube circuit is filled with a heat transfer medium, and the heat dissipation device also includes a refrigerant channel or fins, and the refrigerant channel surrounds the thermal superconducting tube circuit.

2. The battery module according to claim 1, characterized in that: The upper end or the lower end or both ends of the heat spreader have right-angled edges, which increases the contact area between the heat spreader and the flexible insulating thermal conductive sheet, while stabilizing and protecting the battery core.

3. The battery module according to claim 2, characterized in that: The two polarity terminals of the battery cell are respectively on two opposite sides of the battery cell.

4. The battery module according to claim 3, characterized in that: A flexible insulating heat-conducting sheet is sandwiched between the heat spreader and the battery core, and between the heat spreader, the battery core and the heat dissipation device.

5. The battery module according to claim 1, characterized in that: The heat dissipation device has a refrigerant channel, and both ends of the refrigerant channel are not closed on the heat dissipation device. The refrigerant enters from the refrigerant channel inlet, absorbs heat or releases heat, and then flows out from the refrigerant channel outlet.

6. The battery module according to claim 1, characterized in that: The heat sink is provided with fins, which are arranged at a certain angle θ and connected to the heat sink, wherein 0°<θ<180°.

7. A battery pack, characterized in that: The invention comprises at least two battery modules as claimed in any one of claims 1 to 6 which are stacked or arranged side by side.

8. An electric vehicle, characterized in that: Comprising the battery pack as claimed in claim 7.

9. A power grid system, characterized in that: Comprising the battery pack as claimed in claim 7, the power grid system is a smart grid system, a wind power system or a solar power system.

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