Battery module, battery pack and electric device

Abstract

The utility model relates to the battery module which comprises a box body, a plurality of battery cells, a sealing plate and sealant, and the cooling liquid can circulate in the immersion bin and directly exchange heat with the battery cells, so that heat generated by the battery cells during working can be taken away in time, and the temperature in the battery module is maintained in a proper range. Furthermore, an annular flange extending in the circumferential direction of the shell is formed on the cover plate, so that the bonding area between the sealant and the battery cell can be increased. Moreover, the sealant can be bonded with the side wall of the shell, so that two vertical bonding interfaces can be formed between the sealant and the battery cell by matching the cover plate with the shell. Therefore, the sealing performance between the battery cell and the sealing plate can be obviously improved, and the cooling liquid in the immersion bin is not easy to leak even after being used for a long time. Therefore, the battery module has relatively high reliability. In addition, the utility model also provides a battery pack and an electric device.

Description

Technical Field

[0001] The utility model relates to the technical field of new energy, and in particular to a battery module, a battery pack and an electric device. Background Art

[0002] With the continuous development of new energy vehicles, there is a demand for fast charging of lithium battery products as power batteries. However, when the fast charging rate reaches 4C or above, the heat is serious, and air cooling and indirect liquid cooling can no longer meet the thermal management requirements. More and more power batteries have adopted immersion liquid cooling. The immersion liquid cooling method directly immerses the battery cell in the coolant, which has obvious advantages such as low thermal resistance and high heat transfer efficiency.

[0003] The immersion liquid cooling method requires the coolant to be sealed and isolated to prevent the coolant from adversely affecting the circuit in the module. At present, most power batteries use cylindrical batteries. Compared with square shell batteries, cylindrical batteries are smaller in size and more in number, resulting in more interfaces in the structural parts of the module and difficulty in sealing. After long-term use, the coolant may leak due to sealing failure, resulting in a series of problems such as short circuit and failure. Utility Model Content

[0004] Based on this, it is necessary to provide a battery module, a battery pack and an electrical device with higher reliability to address the above problems.

[0005] A battery module, comprising:

[0006] A box body is formed with a containing cavity;

[0007] A plurality of battery cells are accommodated in the accommodating cavity, each of the battery cells comprises a shell, a pole and a cover plate, the cover plate is arranged at one end of the shell near the pole, and the edge of the cover plate protrudes along the radial outer side of the shell and forms an annular flange extending along the circumference of the shell;

[0008] A sealing plate is installed in the accommodating cavity and is surrounded by the inner wall of the box to form an immersion chamber for containing the coolant, a plurality of fixing holes are opened on the sealing plate, a plurality of the battery cells are respectively inserted into the plurality of fixing holes and the cover plate is located on a side of the sealing plate facing away from the immersion chamber; and

[0009] The sealant fills the annular flange and the gap between the shell and the sealing plate to seal the immersion chamber.

[0010] In one of the embodiments, a plurality of positioning grooves are formed at the bottom of the box body, and a through hole is opened at the bottom of the positioning grooves. A plurality of battery cells can be respectively placed in the plurality of positioning grooves and cover the plurality of through holes, and the explosion-proof valve of each battery cell is arranged relative to the corresponding through hole.

[0011] In one of the embodiments, a sealing groove is formed at the bottom of the positioning groove along the circumference of the through hole, and a sealing ring is accommodated in the sealing groove.

[0012] In one of the embodiments, a liquid inlet assembly and a liquid outlet assembly are provided on the side wall of the box body, and both the liquid inlet assembly and the liquid outlet assembly are connected to the immersion chamber.

[0013] In one embodiment, the shell is cylindrical, the cover plate is annular, and the diameter of the cover plate is larger than the diameter of the shell. The cover plate covers the end surface of the shell where the pole is provided and exposes the pole.

[0014] In one of the embodiments, the outer periphery of the shell is covered with an insulating layer, and the insulating layer isolates the shell from the cooling liquid in the immersion tank.

[0015] In one of the embodiments, the insulating layer forms blank areas at both ends of the shell in the length direction, and the blank areas at both ends are located outside the immersion chamber.

[0016] In one of the embodiments, a CCS assembly is further included, and the CCS assembly is installed on a side of the sealing plate facing away from the immersion chamber.

[0017] In the above-mentioned battery module, the coolant can circulate in the immersion chamber and directly exchange heat with the battery cell, so that the heat generated by the battery cell can be taken away in time, thereby maintaining the temperature inside the battery module within a suitable range. Furthermore, since the cover plate is formed with an annular flange extending along the circumference of the shell, the bonding area between the sealant and the battery cell can be increased. Moreover, the sealant can also be bonded to the side wall of the shell, so the cover plate and the shell can cooperate to form two vertical bonding interfaces between the sealant and the battery cell. Therefore, the sealing performance between the battery cell and the sealing plate can be significantly improved, and the coolant in the immersion chamber is not easy to leak even after long-term use. It can be seen that the above-mentioned battery module has high reliability.

[0018] A battery pack comprises a plurality of battery modules as described in any one of the preferred embodiments above, wherein the plurality of battery modules are electrically connected in series and / or in parallel.

[0019] An electrical device comprises a battery module as described in any one of the preferred embodiments above or a battery pack as described in the preferred embodiments above. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 This is a schematic diagram of the structure of a battery module in a preferred embodiment of the utility model;

[0022] Figure 2 for Figure 1 An exploded view of the battery module shown;

[0023] Figure 3 for Figure 2 A partial enlarged schematic diagram of a box in the battery module shown;

[0024] Figure 4 for Figure 1 A transverse cross-sectional view of the battery module shown;

[0025] Figure 5 for Figure 4 An enlarged schematic diagram of a local A in the battery module shown;

[0026] Figure 6 for Figure 1 A schematic diagram of the structure of the battery cell in the battery module shown;

[0027] Figure 7 for Figure 6 A partial enlarged schematic diagram of the battery cell shown. DETAILED DESCRIPTION

[0028] In order to make the above-mentioned purposes, features and advantages of the utility model more obvious and easy to understand, the specific implementation methods of the utility model are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the utility model. However, the utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the utility model, so the utility model is not limited by the specific embodiments disclosed below.

[0029] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0030] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0031] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like 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 an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0033] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0034] The utility model discloses an electric device, a battery pack and a battery module, wherein the electric device comprises the battery pack or the battery module, and can be provided with electric energy by the battery pack and the battery module. The battery pack comprises a plurality of the battery modules, and the plurality of the battery modules can be electrically connected in parallel, in series or in combination of parallel and series.

[0035] The above-mentioned electrical devices can be vehicles, ships, spacecraft, electric toys, electric tools, energy storage equipment, amusement equipment, elevators and lifting equipment, etc. Vehicles can be fuel vehicles, gas vehicles or new energy vehicles, and new energy vehicles can be pure electric vehicles, hybrid vehicles or extended-range vehicles, etc.; spacecraft include aircraft, rockets, space shuttles and spacecraft, etc.; electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys or electric airplane toys, etc.; electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators and electric planers, etc.; energy storage equipment can be energy storage walls, base station energy storage, container energy storage, etc.; amusement equipment can be carousels, jumping machines, etc.

[0036] This application does not impose any special restrictions on the above-mentioned power-consuming devices. For new energy vehicles, the above-mentioned battery packs and battery modules can be used as driving power sources, thereby replacing fossil fuels to provide driving power.

[0037] See also Figure 1 and Figure 2 The battery module 10 in the preferred embodiment of the present invention includes a box body 100, a battery cell 200, a sealing plate 300 and a sealant 400.

[0038] The housing 100 is formed with a receiving chamber 101, and the receiving chamber 101 is used to receive components such as coolant, battery cells 200 and sealing plates 300. The shape of the housing 100 can be set according to actual needs, and is generally in the shape of a rectangular parallelepiped. Specifically in the present embodiment, the side wall of the housing 100 is provided with a liquid inlet assembly 110 and a liquid outlet assembly 120. Both the liquid inlet assembly 110 and the liquid outlet assembly 120 can be holes provided on the side wall of the housing 100, or joints embedded in the side wall of the housing 100. The liquid inlet assembly 110 and the liquid outlet assembly 120 can be connected to an external coolant circulation system (not shown), so that the coolant can circulate in the housing 100, thereby cooling the battery cells 200 accommodated in the receiving chamber 101.

[0039] The battery cell 200 is a single battery cell. A plurality of battery cells 200 are provided, and the plurality of battery cells 200 can be electrically connected in series, in parallel, or in a combination of series and parallel, and are generally distributed in the accommodating cavity 101 in a matrix arrangement.

[0040] Please also read Figure 3 In this embodiment, a plurality of positioning grooves 130 are formed at the bottom of the box body 100, and a through hole 131 is opened at the bottom of the positioning groove 130. A plurality of battery cells 200 can be respectively placed in the plurality of positioning grooves 130 and cover the plurality of through holes 131, and an explosion-proof valve (not shown) of each battery cell 200 is arranged opposite to the corresponding through hole 131.

[0041] The plurality of battery cells 200 are positioned by the plurality of positioning grooves 130, so that the battery cells 200 can be easily assembled and the displacement of the battery cells 200 can be effectively prevented during use. Since the battery cells 200 in the embodiment are cylindrical, the positioning grooves 130 are circular.

[0042] The plurality of positioning grooves 130 are generally distributed in a matrix at the bottom of the box 100, and the positioning grooves 130 in two adjacent columns are staggered along the arrangement direction, and the positioning grooves 130 in one column are aligned with the area between two adjacent positioning grooves 130 in the other column. In this way, the positioning grooves 130 can be arranged more closely, thereby increasing the number of positioning grooves 130 that can be set per unit area, and further increasing the number of battery cells 200 in the battery module 10, which helps to improve the energy density of the battery module 10.

[0043] Moreover, since the explosion-proof valve of each battery cell 200 is arranged opposite to the corresponding through hole 131, once the battery cell 200 has thermal runaway, the high-temperature gas and electrolyte ejected from the explosion-proof valve will be directly discharged to the outside of the box body 100 through the corresponding through hole 131, thereby avoiding sudden changes in pressure and temperature inside the battery module 10.

[0044] The battery cell 20 can be sealed with the assembly surface of the positioning groove 130, thereby preventing the coolant from leaking outward through the through hole 131. Furthermore, in the present embodiment, a sealing groove (not shown) is provided at the bottom of the positioning groove 130 along the circumference of the through hole 111, and a sealing ring (not shown) is accommodated in the sealing groove. When the battery cell 200 is placed in the positioning groove 130, the bottom of the battery cell 200 will cooperate with the sealing ring to form a better seal, thereby improving the sealing performance between the battery cell 200 and the positioning groove 130. Moreover, since the sealing groove can also limit the sealing ring, it can effectively prevent the sealing ring from shifting, thereby ensuring the reliability of the seal.

[0045] Please also read Figure 6 and Figure 7 Each battery cell 200 includes a housing 210, a pole 220 and a cover plate 230. The cover plate 230 is disposed at one end of the housing 210 close to the pole 220, and the edge of the cover plate 230 protrudes radially outward from the housing 210 and is formed on an annular flange (not marked in the figure) extending along the circumference of the housing 210.

[0046] The housing 210 is generally formed of metal materials such as stainless steel and aluminum. The housing 210 is conductive and usually serves as an electrode of the battery cell 200. The pole 220 is disposed on an end face of the housing 210 in the length direction and serves as another electrode of the battery cell 200. The explosion-proof valve is usually disposed at one end of the housing 210 away from the pole 220. The material of the cover plate 230 can be the same as that of the housing 210, and can be assembled with the housing 210 by welding or other methods.

[0047] Specifically in this embodiment, since the battery cell 200 is a cylindrical battery, the housing 210 is cylindrical. Further, the cover plate 230 is annular, and the diameter of the cover plate 230 is larger than the diameter of the housing 210. The cover plate 230 covers the end surface of the housing 210 where the pole 220 is provided and exposes the pole 220.

[0048] The middle of the cover plate 230 is provided with a position avoidance hole (not shown) for avoiding the pole 220. When assembling, the cover plate 230 is first pressed against the end surface of the housing 210, and then the two are welded. Usually, the diameter of the cover plate is 1 to 4 mm larger than the diameter of the housing 210, so the width of the annular flange formed is also about 1 to 4 mm.

[0049] Please also read Figure 4 and Figure 5 The sealing plate 300 is installed in the accommodating chamber 101 and is surrounded by the inner wall of the box body 100 to form an immersion chamber 102. The immersion chamber 102 is a part of the accommodating chamber 101 and is used to contain the coolant. More specifically, the liquid inlet assembly 110 and the liquid outlet assembly 120 are both connected to the immersion chamber 102. Therefore, the coolant can circulate in the immersion chamber 102 with the help of the liquid inlet assembly 110 and the liquid outlet assembly 120.

[0050] Furthermore, the sealing plate 300 is provided with a plurality of fixing holes 310, and the plurality of battery cells 200 are respectively inserted through the plurality of fixing holes 310, and the cover plate 230 is located on the side of the sealing plate 300 facing away from the immersion chamber 102. The fixing holes 310 can limit the end of the battery cell 200 away from the explosion-proof valve, so that the two ends of the battery cell 200 can be better limited in position in cooperation with the positioning groove 130, thereby improving the stability of the battery cell 200 in the box 100.

[0051] Moreover, the battery cell 200 and the sealing plate 300 are sealed by the sealant 400, so the coolant can only flow in the immersion chamber 102 and will not spread to the top of the sealing plate 300. In this way, the pole 220 of the battery cell 200 can be separated from the coolant, thereby preventing the electrical performance of the battery cell 200 from being affected by the coolant.

[0052] Specifically in this embodiment, the battery module 10 further includes a CCS assembly 500, which is mounted on the side of the sealing plate 300 facing away from the immersion chamber 102. The CCS assembly 500 generally includes components such as a plastic plate, a low-voltage circuit, and a conductive bar, and can electrically connect multiple battery cells 200 and monitor the battery cells 200 in real time by collecting various parameters of the battery cells 200. Moreover, under the isolation effect of the sealing plate 300, the CCS assembly 500 will not be affected by the coolant in the immersion chamber 102, thereby ensuring the stability of the electrical performance.

[0053] The sealant 400 fills the gap between the annular flange and the housing 210 and the sealing plate 300, thereby achieving a seal between the battery cell 200 and the sealing plate 300, and further sealing the immersion chamber 102. Specifically, after the sealing plate 300 and the battery cell 200 are assembled, the sealant 400 can be obtained by injecting glue. In addition, the sealant 400 in a film-like shape with a preset shape can also be pre-processed and set between the battery cell 200 and the sealing plate 300 during the assembly process.

[0054] Since the cover plate 230 is formed with an annular flange extending along the circumference of the shell 210, the bonding area between the sealant 400 and the battery cell 200 can be increased. The larger the bonding area, the higher the reliability of the seal. In addition, the sealant 400 can also be bonded to the side wall of the shell 210, so the cover plate 230 and the shell 210 can cooperate to form two vertical bonding interfaces between the sealant 400 and the battery cell 200, so that a more three-dimensional sealing surface can be formed between the battery cell 200 and the sealing plate 300. Therefore, the sealing performance between the battery cell 200 and the sealing plate 300 can be significantly improved, and the coolant in the immersion chamber 102 will not leak to the top of the sealing plate 300 and adversely affect the electrical performance between the battery cells 200 even after long-term use, and the reliability of the battery cell module 10 is significantly improved.

[0055] Please refer again Figure 6 and Figure 7 In this embodiment, the outer periphery of the shell 210 is covered with an insulating layer 240 , and the insulating layer 240 isolates the shell 210 from the coolant in the immersion chamber 102 .

[0056] Since the housing 210 is formed of metal as an electrode of the battery cell 200, it may be exposed to the coolant directly, which may cause corrosion, short circuit and other risks, thereby affecting the safety of the battery cell 200. However, under the isolation effect of the insulating layer 240, the housing 210 will not be in direct contact with the coolant. In this way, the requirements for the electrical insulation and stability of the coolant can be reduced, and there is no need to worry about the coolant being electrolyzed and the housing 210 being corroded by the coolant.

[0057] Furthermore, in the present embodiment, the insulating layer 240 forms blank areas (not marked in the figure) at both ends of the shell 210 in the length direction, and the blank areas at both ends are located outside the immersion chamber 102 .

[0058] That is, the edge of the insulating layer 240 does not have to be aligned with the edges of the two ends of the shell 210, and the height of the insulating layer 240 can be less than the height of the shell 210. In this way, the technical requirements for the insulation layer 240 coating can be reduced, thereby improving the qualified rate of the battery cell 200 and reducing the cost of insulation coating. Moreover, since the blank areas at both ends are located outside the immersion chamber 102, there is no exposed shell 210 in the immersion chamber 102, so that the stability of the battery module 10 will not be affected.

[0059] Specifically, during the assembly process of the battery module 10, the blank area near one end of the pole 220 can be set on the side of the sealing plate 300 facing away from the immersion chamber 102 and sealed with a sealant 400 to prevent it from being exposed in the immersion chamber 102. In addition, the depth of the positioning groove 130 is set to be greater than the width of the blank area. In this way, the blank area near one end of the explosion-proof valve can be buried in the positioning groove 130, thereby preventing it from being exposed in the immersion chamber 102.

[0060] In the above-mentioned battery module 10, the coolant can circulate in the immersion chamber 102 and directly exchange heat with the battery cell 200, so that the heat generated by the operation of the battery cell 200 can be taken away in time, thereby maintaining the temperature inside the battery module 10 within a suitable range. Furthermore, since the cover plate 230 is formed with an annular flange extending along the circumference of the shell 210, the bonding area between the sealant 400 and the battery cell 200 can be increased. Moreover, the sealant 400 can also be bonded to the side wall of the shell 210, so the cover plate 230 and the shell 210 can cooperate to form two vertical bonding interfaces between the sealant 400 and the battery cell 200. Therefore, the sealing performance between the battery cell 200 and the sealing plate 300 can be significantly improved, and the coolant in the immersion chamber 102 is not easy to leak even after long-term use. It can be seen that the above-mentioned battery module 10 has high reliability.

[0061] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0062] The above-mentioned embodiments only express several implementation methods of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A battery module, characterized in that: include: A box body is formed with a containing cavity; A plurality of battery cells are accommodated in the accommodating cavity, each of the battery cells comprises a shell, a pole and a cover plate, the cover plate is arranged at one end of the shell near the pole, and the edge of the cover plate protrudes along the radial outer side of the shell and forms an annular flange extending along the circumference of the shell; A sealing plate is installed in the accommodating cavity and is surrounded by the inner wall of the box to form an immersion chamber for containing the coolant, a plurality of fixing holes are opened on the sealing plate, a plurality of the battery cells are respectively inserted into the plurality of fixing holes and the cover plate is located on a side of the sealing plate facing away from the immersion chamber; and The sealant fills the annular flange and the gap between the shell and the sealing plate to seal the immersion chamber.

2. The battery module according to claim 1, characterized in that: A plurality of positioning grooves are formed at the bottom of the box body, and a through hole is opened at the bottom of the positioning groove. A plurality of battery cells can be respectively placed in the plurality of positioning grooves and cover the plurality of through holes, and the explosion-proof valve of each battery cell is arranged opposite to the corresponding through hole.

3. The battery module according to claim 2, characterized in that: A sealing groove is formed at the bottom of the positioning groove along the circumference of the through hole, and a sealing ring is accommodated in the sealing groove.

4. The battery module according to claim 1, characterized in that: The side wall of the box body is provided with a liquid inlet assembly and a liquid outlet assembly, and the liquid inlet assembly and the liquid outlet assembly are both communicated with the immersion chamber.

5. The battery module according to claim 1, characterized in that: The shell is cylindrical, the cover is annular, and the diameter of the cover is larger than the diameter of the shell. The cover is arranged on the end surface of the shell where the pole is arranged and exposes the pole.

6. The battery module according to claim 1, characterized in that: The outer periphery of the shell is covered with an insulating layer, and the insulating layer isolates the shell from the coolant in the immersion tank.

7. The battery module according to claim 6, characterized in that: The insulating layer forms blank areas at both ends of the shell in the length direction, and the blank areas at both ends are located outside the immersion chamber.

8. The battery module according to claim 1, characterized in that: It also includes a CCS component, which is installed on a side of the sealing plate facing away from the immersion tank.

9. A battery pack, characterized in that: The invention comprises a plurality of battery modules according to any one of claims 1 to 8, wherein the plurality of battery modules are electrically connected in series and / or in parallel.

10. An electrical device, characterized in that: It comprises a battery module as described in any one of claims 1 to 8 or a battery pack as described in claim 9.

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