Battery pack and electric device

Abstract

The utility model relates to the technical field of batteries, and discloses a battery pack and an electric device. The power utilization device comprises a battery pack, the battery pack comprises a lower box body, a battery module and an upper cover, the lower box body comprises a box main body and a bottom plate, the bottom plate is connected to the bottom end of the box main body, an exhaust channel is defined by the bottom plate and the box main body, and the side face of the box main body is provided with an anti-explosion valve used for communicating the exhaust channel with the exterior of the lower box body; a plurality of exhaust holes communicated with the exhaust channel are formed in the bottom surface of the box main body; the battery module comprises a plurality of battery cells arranged in the box main body, and the pressure release valves of the battery cells are arranged in one-to-one correspondence with the exhaust holes; the upper cover is buckled at the top end of the box body, and the upper cover and the box body are sealed and fixed through sealant. According to the battery pack provided by the utility model, electrified high-temperature gas can be prevented from entering the inner cavity of the box main body to influence other parts, electrical safety risks such as short circuit and the like are avoided, and the safety performance of the battery pack is improved.

Description

Technical Field

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

[0002] At present, with the development of new energy vehicle industry, batteries are widely used. In the development of battery technology, not only the performance of batteries but also the safety of batteries need to be considered.

[0003] The battery pack of the prior art has a high thermal safety risk. The battery pack box usually contains multiple battery cells. When one of the battery cells experiences thermal runaway, the battery cell will discharge a large amount of charged high-temperature gas. If it is not discharged in time, it will fill the entire inner cavity of the box. The high-temperature gas will not only melt the plastic insulation layer of the electrical components and cause a short circuit problem, but may also trigger a short circuit in the remaining battery cells except the single battery cell with thermal runaway, thereby causing heat spread, which can easily cause serious safety accidents and has poor safety performance.

[0004] Therefore, there is an urgent need to provide a battery pack and an electrical device to solve the above problems. Utility Model Content

[0005] One purpose of the utility model is to provide a battery pack, in which high-temperature thermal runaway gas generated by thermal runaway of the battery cell can be directly discharged to the outside from the exhaust channel at the bottom without being transmitted to the inside of the battery pack, thereby not causing electrical safety risks such as short circuit, thereby improving the safety performance of the battery pack.

[0006] Another object of the present invention is to provide an electrical device, which can improve the safety performance of the electrical device by providing the above-mentioned battery pack.

[0007] In order to achieve the above purpose, the utility model is implemented through the following technical solutions:

[0008] A battery pack, comprising:

[0009] The lower box body comprises a box body and a bottom plate, wherein the bottom plate is connected to the bottom end of the box body and defines an exhaust passage with the box body, an explosion-proof valve for connecting the exhaust passage and the outside of the lower box body is provided on the side of the box body, and a plurality of exhaust holes connected with the exhaust passage are provided on the bottom surface of the box body;

[0010] A battery module, comprising a plurality of battery cells arranged inside the box body, wherein a pressure relief valve of each battery cell is arranged in one-to-one correspondence with the exhaust hole;

[0011] The upper cover is buckled on the top of the box body, and the upper cover and the box body are sealed and fixed by a sealant.

[0012] As an optional solution, the bottom end of the box body is ringed with a positioning groove that matches the contour of the bottom plate, and the bottom plate is accommodated in the positioning groove and welded to the bottom end of the box body.

[0013] As an optional solution, a glue groove is provided at the top of the box body, and the glue groove is used to fill the sealant, and a positioning rib matching the glue groove is provided at the bottom edge of the upper cover.

[0014] As an optional solution, the battery module also includes a plastic plate for supporting the plurality of battery cells, a plurality of mounting grooves are provided on one side of the plastic plate, one end of each battery cell equipped with the pressure relief valve is accommodated in the corresponding mounting groove, a pressure relief hole is provided at the bottom of each mounting groove, and the pressure relief hole is partially located in the corresponding exhaust hole.

[0015] As an optional solution, each of the pressure relief holes is provided with an annular convex rib on one end edge away from the battery core, and each of the annular convex ribs is inserted into the corresponding exhaust hole;

[0016] And / or the plastic plate is provided with a plurality of weight-reducing holes arranged at intervals.

[0017] As an optional solution, one of the plastic plate and the bottom surface of the box body is provided with a positioning hole, and the other of the two is provided with a first positioning pin plugged into and matched with the positioning hole; and / or

[0018] One of the peripheral side of the plastic plate and the peripheral side of the box body is provided with a positioning groove, and the other of the two is provided with a second positioning pin plugged and matched with the positioning groove.

[0019] As an optional solution, two glue blocking beams are arranged at intervals along the length direction of the box body, and the two glue blocking beams and the side walls of the box body together define a first accommodating cavity. The battery module is arranged in the first accommodating cavity, and the first accommodating cavity is filled with structural adhesive.

[0020] As an optional solution, the battery pack further includes a CSS assembly, the CSS assembly includes a bracket and a plurality of busbars, the bracket cover is provided on the plurality of battery cells, and the busbar is used to electrically connect the positive electrode and the negative electrode of two adjacent battery cells;

[0021] The bracket is provided with a plurality of heat riveting posts corresponding to the busbars one by one. The busbars are provided with through holes. The heat riveting posts are configured to pass through the through holes and then be heat riveted to fix the busbars on the bracket.

[0022] As an optional solution, the battery pack further includes a BMS module disposed in the box body and located beside the battery module, and the BMS module includes a first positive electrode stud and a first negative electrode stud disposed at the top thereof;

[0023] The plurality of busbars include two output series rows, which are arranged adjacent to the BMS module, wherein one of the output series rows is provided with a positive output terminal, and the other of the output series rows is provided with a negative output terminal, the first positive stud is passed through the positive output terminal, and the first negative stud is passed through the negative output terminal.

[0024] As an optional solution, the battery pack also includes a liquid cooling plate, which is arranged on the top of the battery module, and a thermal conductive adhesive is provided between the liquid cooling plate and the battery module. The liquid cooling plate is provided with two straight tubes for liquid inlet and liquid outlet, respectively, and both straight tubes extend to the outside of the upper cover.

[0025] As an optional solution, the liquid cooling plate includes a stamped plate and a flat plate. The flat plate is connected to a side of the stamped plate close to the battery module to form a closed liquid cooling channel. The flat plate is in contact with the thermal conductive adhesive, and the straight tube is connected to the stamped plate.

[0026] As an optional solution, the upper cover is provided with two recessed portions, and the two straight tubes are respectively located in the corresponding recessed portions.

[0027] As an optional solution, each of the straight tubes is provided with a flange, and the flange is located on the inner side of the upper cover, and the flange is provided with a first sealing groove arranged around the straight tube and a second sealing groove and a connecting hole arranged in a stepped shape;

[0028] The battery pack also includes a sealing assembly, which includes a first sealing ring, a second sealing ring, a pressure plate and a fastener. The first sealing ring is accommodated in the first sealing groove, the second sealing ring is accommodated in the second sealing groove, the pressure plate is located on the outside of the upper cover and is sleeved on the straight tube, and the fastener is sequentially passed through the pressure plate and the upper cover and then matched with the connecting hole.

[0029] An electrical device comprises the above-mentioned battery pack.

[0030] The beneficial effects of the utility model are:

[0031] In the battery pack provided by the utility model, when thermal runaway occurs in one of the battery cells, the charged high-temperature gas discharged from the pressure relief valve of the battery cell will be promptly discharged into the exhaust channel through the exhaust holes at the corresponding positions, and then discharged to the outside of the lower box body by the explosion-proof valve, thereby achieving smooth exhaust and pressure relief, preventing the charged high-temperature gas from entering the inner cavity of the box body and affecting other components, avoiding electrical safety risks such as short circuit, and improving the safety performance of the battery pack.

[0032] The electric device provided by the utility model can improve the safety performance of the electric device by arranging the above-mentioned battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to explain the embodiments of the utility model or the technical solutions in the prior art more clearly and easily, the following is a brief introduction to the drawings required for use in the embodiments or the description of the prior art. The drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] Figure 1 It is a schematic diagram of the structure of a battery pack provided by an embodiment of the utility model;

[0035] Figure 2 is an exploded view of a battery pack provided by an embodiment of the utility model;

[0036] Figure 3 It is an exploded view of the lower box body and the upper cover provided by the embodiment of the utility model;

[0037] Figure 4 is a cross-sectional view of the lower box provided by an embodiment of the utility model;

[0038] Figure 5 It is a partial enlarged cross-sectional view of the cooperation between the lower box and the battery module provided by the embodiment of the utility model;

[0039] Figure 6 It is a partial enlarged cross-sectional view of the lower box body at the explosion-proof valve provided by the embodiment of the utility model;

[0040] Figure 7 It is a structural schematic diagram of the box body provided by an embodiment of the utility model at a first viewing angle;

[0041] Figure 8 This is a schematic diagram of the box body provided by the embodiment of the utility model at a second viewing angle;

[0042] Fig. 9 It is a partial enlarged cross-sectional view of the box body at the glue groove provided by the embodiment of the utility model;

[0043] Fig.10It is a partial enlarged cross-sectional view of the box body and the upper cover provided by the embodiment of the utility model matching at the glue groove;

[0044] Fig.11 It is a structural schematic diagram of the plastic plate provided by an embodiment of the utility model at a first viewing angle;

[0045] Fig.12 is a schematic structural diagram of a plastic plate provided by an embodiment of the utility model at a second viewing angle;

[0046] Fig.13 It is a structural diagram of a CSS component provided by an embodiment of the utility model;

[0047] Fig.14 It is a structural schematic diagram of a BMS module provided by an embodiment of the utility model;

[0048] Fig.15 It is a schematic diagram of the structure of the upper cover provided by an embodiment of the utility model at a first viewing angle;

[0049] Fig.16 is a schematic structural diagram of the upper cover provided by an embodiment of the utility model at a second viewing angle;

[0050] Fig.17 This is a schematic structural diagram of a battery pack provided by an embodiment of the utility model without the upper cover and the liquid cooling plate;

[0051] Fig.18 It is a schematic diagram of the structure of the liquid cooling plate provided by the embodiment of the utility model;

[0052] Fig.19 yes Fig.17 A partial enlarged view of the straight pipe in FIG.

[0053] Fig. 20 It is a partial enlarged cross-sectional view of the liquid cooling plate and the sealing assembly provided by the embodiment of the utility model after being matched.

[0054] In the figure:

[0055] 10. Lower box body; 11. Box body; 111. Exhaust hole; 112. Positioning groove; 113. Glue groove; 114. First positioning pin; 115. Second positioning pin; 116. First accommodating chamber; 117. Second accommodating chamber; 118. Mounting stud; 12. Bottom plate; 13. Exhaust channel; 14. Explosion-proof valve; 15. Sealant; 16. Glue blocking beam; 17. Structural glue;

[0056] 20. Battery module; 21. Battery cell; 211. Positive electrode; 212. Negative electrode; 22. Plastic plate; 221. Mounting groove; 222. Pressure relief hole; 223. Annular rib; 224. Weight reduction hole; 225. Positioning hole; 226. Positioning groove;

[0057] 30. Upper cover; 31. Positioning rib; 32. Output copper bar; 321. Output stud; 33. Assembly socket; 34. Recessed part; 35. Reserved hole; 36. Plastic plug;

[0058] 40, CSS assembly; 41, bracket; 411, hot riveting column; 42, bus bar; 421, middle series row; 4211, positive electrode portion; 4212, negative electrode portion; 4213, first circular hole; 422, output series row; 4221, positive electrode output terminal; 4222, negative electrode output terminal; 4223, second circular hole;

[0059] 50. BMS module; 51. first positive stud; 52. first negative stud; 53. second positive stud; 54. second negative stud; 55. first collection socket; 56. second collection socket; 57. mounting foot; 58. nut;

[0060] 60. PCB board; 61. Collection connector; 62. Collection nickel sheet;

[0061] 70, liquid cooling plate; 71, stamping plate; 72, flat plate; 73, thermal conductive adhesive; 74, straight pipe; 75, flange; 751, first sealing groove; 752, second sealing groove; 753, connecting hole;

[0062] 80. Sealing assembly; 81. First sealing ring; 82. Second sealing ring; 83. Pressing plate; 84. Fastener;

[0063] 90. Wiring harness assembly; 91. First wiring harness; 92. Second wiring harness. DETAILED DESCRIPTION

[0064] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0065] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" 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. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0066] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0067] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0068] like Figure 1 and Figure 2 As shown, this embodiment provides a battery pack, including a lower box 10, a battery module 20 and an upper cover 30. The battery module 20 includes a plurality of cells 21 arranged in a square matrix. The plurality of cells 21 are accommodated in the cavity of the lower box 10. The upper cover 30 is buckled at the top opening of the lower box 10 to form a closed cavity. The lower box 10 can be made of aluminum alloy, and the upper cover 30 can be made of plastic, which is lightweight. The upper cover 30 and the box body 11 can be sealed and fixed by a sealant 15, which reduces costs and is convenient and quick.

[0069] However, the battery pack of the prior art has a high thermal safety risk. When one of the battery cells 21 experiences thermal runaway, the battery cell 21 will discharge a large amount of charged high-temperature gas. If it is not discharged in time, it will fill the inner cavity of the entire box. The high-temperature gas will not only melt the plastic insulation layer of the electrical components and cause a short circuit problem, but may also trigger a short circuit in the remaining battery cells 21 except the single battery cell 21 with thermal runaway, thereby causing heat spread, which can easily cause serious safety accidents. The safety performance is poor and may also melt the upper cover 30 of the battery pack, causing the battery pack to rupture. Flames may be seen from the outside of the battery pack, but it does not meet the safety requirements of GB38031.

[0070] In order to solve the above problems, in this embodiment, Figures 3 to 7As shown, the lower box body 10 includes a box body 11 and a bottom plate 12, the bottom plate 12 is connected to the bottom end of the box body 11 and defines an exhaust channel 13 together with the box body 11, and an explosion-proof valve 14 is provided on the side of the box body 11 for connecting the exhaust channel 13 and the outside of the lower box body 10, and a plurality of exhaust holes 111 connected to the exhaust channel 13 are provided on the bottom surface of the box body 11, and the plurality of exhaust holes 111 are arranged in one-to-one correspondence with the plurality of battery cells 21, and the battery cells 21 all have a pressure relief valve, and the pressure relief valve of each battery cell 21 is arranged toward the corresponding exhaust hole 111 and is directly connected to the corresponding exhaust hole 111.

[0071] When thermal runaway occurs in one of the battery cells 21, the charged high-temperature gas discharged from the pressure relief valve of the battery cell 21 will be promptly discharged into the exhaust channel 13 through the exhaust hole 111 at the corresponding position, and then discharged to the outside of the lower box body 10 by the explosion-proof valve 14, thereby achieving smooth exhaust and pressure relief, preventing the charged high-temperature gas from entering the box body 11 and affecting other battery cells 21, electrical components, and plastic upper cover 30, thereby avoiding the risk of electrical short circuit and the risk of rupture of the upper cover 30, and improving the safety performance of the battery pack.

[0072] In an optional embodiment, if Figure 8 As shown, the bottom of the box body 11 is provided with a positioning groove 112 that matches the contour of the bottom plate 12, and the positioning groove 112 is provided at the edge of the bottom opening of the box body 11, and the bottom plate 12 is accommodated in the positioning groove 112 and is welded and fixed to the bottom of the box body 11. In other words, the box body 11 and the bottom plate 12 are formed separately and then fixed together by welding, which can facilitate the processing and manufacturing of the box body 11 and the bottom plate 12. The positioning groove 112 can position the installation of the bottom plate 12, and during the welding process, the bottom of the positioning groove 112 can provide good support for the bottom plate 12 to ensure the welding quality.

[0073] In an optional embodiment, the box body 11 and the bottom plate 12 are welded together by stir friction welding, which has the characteristics of high efficiency, low consumption, low welding temperature, and small deformation of the welded workpiece. In another optional embodiment, the box body 11 and the bottom plate 12 can also be integrally die-cast, such as sand die-casting.

[0074] In an optional embodiment, in order to achieve the sealing and fixing of the upper cover 30 and the box body 11, as shown in FIG. Figure 3 and Fig. 9 As shown, a glue groove 113 is formed around the top of the box body 11, and the glue groove 113 is used to fill the sealant 15, and a positioning rib 31 is formed around the bottom edge of the upper cover 30 to match the glue groove 113. Fig. 9 and Fig.10Before assembling the upper cover 30, first use a glue-applying tool to apply sealant 15 in the glue groove 113, fill the sealant 15 to about two-thirds of the height in the glue groove 113, and then install the upper cover 30. During installation, insert the positioning rib 31 at the bottom of the upper cover 30 into the glue groove 113 to achieve the positioning installation of the upper cover 30. At the same time, the positioning rib 31 will squeeze the sealant 15, so that the sealant 15 spreads around, and the sealant 15 overflows the glue groove 113 and fills the gap between the upper cover 30 and the box body 11, thereby achieving sealing and fixation between the upper cover 30 and the lower box body 10.

[0075] In an optional implementation, if Figure 2 As shown, the number of battery cells 21 is set to 12, and the 12 battery cells 21 are regularly arranged in three rows and four columns, and the number of exhaust holes 111 corresponds to the number of battery cells 21. In other embodiments, according to actual needs, the number of battery cells 21 can also be adaptively adjusted, which is not specifically limited here.

[0076] In the prior art, the battery cell 21 mostly adopts a square shell battery cell. The capacity of a single battery cell 21 is 19.5Ah and the voltage is 3.66V. Taking the combination of 12 square shell battery cells using 1P12S (1 parallel and 12 series) as an example, the total power J=1×19.5A×3.66V×12=0.856kW, and the total power of the battery pack is relatively low. At this power, the starting ability of the electric vehicle is relatively low.

[0077] In order to solve the above problem, in this embodiment, the battery cell 21 adopts a cylindrical battery cell, specifically a 46XX cylindrical battery cell (46 indicates that the diameter of the battery cell 21 is 46 mm, and XX indicates the height of the battery cell 21), and the gap between two adjacent battery cells 21 is 2 mm. Exemplarily, the height of the battery pack is 160 mm, and the selectable 46XX cylindrical cells include three types of cells 21: 4680, 4695, and 46110. Taking 12 cells 21 in a 1P12S (1 parallel and 12 series) combination as an example, their powers are: J1 = 1×26.5A×3.67V×12=1.167kW (4680 cylindrical cell, capacity is 26.5Ah, voltage is 3.67V); J2 = 1×32.4A×3.67V×12=1.427kW (4695 cylindrical cell, capacity is 32.4Ah, voltage is 3.67V); J3 = 1×38.1A×3.67V×12=1.678kW (46110 cylindrical cell, capacity is 38.1Ah, voltage is 3.67V). From the above, it can be seen that the available power of battery packs using cylindrical cells is higher than that of battery packs using square shell cells. Among them, the battery pack using 46110 cylindrical cells can increase the power by about 2 times. At this power, electric vehicles start faster.

[0078] In an optional embodiment, if Figure 2 and Fig.11 As shown, the battery module 20 also includes a plastic plate 22 for supporting a plurality of battery cells 21. A plurality of mounting grooves 221 are provided on one side of the plastic plate 22. One end of each battery cell 21 equipped with a pressure relief valve is accommodated in a corresponding mounting groove 221 to play a positioning role. The battery cell 21 is supported and fixed in the box body 11 by the plastic plate 22, so that electrical insulation is formed between the battery cell 21 and the box body 11. The plastic plate 22 is used to realize grouping of a plurality of battery cells 21, which helps to reduce the difficulty of grouping and assembling the battery cells 21.

[0079] Combination Figure 5 , Figure 6 indivual Fig.11 A pressure relief hole 222 is provided at the bottom of each mounting groove 221, and a portion of the pressure relief hole 222 is located in the corresponding exhaust hole 111. When thermal runaway occurs in one of the battery cells 21, the charged high-temperature gas discharged from the battery cell 21 enters the exhaust channel 13 through the pressure relief hole 222 in the exhaust hole 111, and is then discharged to the outside of the lower box 10 through the explosion-proof valve 14, achieving smooth exhaust and pressure relief, ensuring exhaust performance, and improving the safety performance of the battery pack.

[0080] In the prior art, some battery packs are complex to group. Generally, the lower shell is formed by welding the end plate and the side plate. After the battery cell 21 is placed in the lower shell, the integrated busbar is welded, and then the upper shell is installed to form a battery module. The battery module is fixed with screws after entering the box. In the battery pack of this embodiment, multiple battery cells 21 are integrated into a group through a plastic plate 22 and then directly put into the box, that is, the CTP solution. After entering the box, the structural glue 17 is poured into the bottom of the battery cell 21 to fix the battery cell 21 and the plastic plate 22 in the box body 11 to ensure the structural strength. Screws and nuts are not required to fix the battery module 20, which simplifies the grouping process, saves the use of many structural parts, and reduces production costs.

[0081] In another optional embodiment, the plastic plate 22 between the battery cell 21 and the box body 11 may be replaced by spraying insulating powder on the bottom surface of the inner side of the box body 11 .

[0082] In an optional embodiment, if Fig.11 and Fig.12 As shown, the plastic plate 22 is provided with a plurality of spaced-apart weight-reducing holes 224. By providing the weight-reducing holes 224, the weight of the plastic plate 22 is reduced while ensuring the structural strength of the plastic plate 22. In addition, the weight-reducing holes 224 can be filled with structural adhesive 17 to increase the bonding contact area between the structural adhesive 17 and the box body 11, thereby ensuring a more secure bonding.

[0083] In an optional embodiment, if Figure 5 and Fig.12As shown, each pressure relief hole 222 has an annular convex rib 223 protruding from the edge of one end away from the battery cell 21, and each annular convex rib 223 is inserted into the corresponding exhaust hole 111. The cooperation between the annular convex rib 223 and the exhaust hole 111 can play a role in positioning the installation position of the plastic plate 22 when the battery module 20 is put into the box.

[0084] In an optional embodiment, if Figure 7 and Fig.11 As shown, the plastic plate 22 is provided with a positioning hole 225, and the bottom surface of the box body 11 is provided with a first positioning pin 114 that is plugged into the positioning hole 225. Through the cooperation between the positioning hole 225 and the first positioning pin 114, the installation position of the plastic plate 22 can be positioned when the battery module 20 is placed in the box. In another optional embodiment, the first positioning pin 114 is provided on the plastic plate 22, and the positioning hole 225 is provided on the bottom surface of the box body 11, which can also achieve the above effect.

[0085] In an optional embodiment, if Figure 7 and Fig.11 As shown, a positioning groove 226 is provided on the circumference of the plastic plate 22, and a second positioning pin 115 is provided on the circumference of the box body 11 to be plugged into and matched with the positioning groove 226. Through the cooperation between the positioning groove 226 and the second positioning pin 115, the installation position of the plastic plate 22 can also be positioned when the battery module 20 is placed in the box. In another optional embodiment, the second positioning pin 115 is provided on the circumference of the plastic plate 22, and the positioning groove 226 is provided on the circumference of the box body 11, which can also achieve the above effect.

[0086] From the above content, it can be known that when the plastic plate 22 is put into the box, the positioning hole 225 thereon cooperates with the first positioning pin 114 as the main positioning, and the positioning groove 226 and the second positioning pin 115 are used as secondary positioning to ensure that each annular rib 223 can be directly opposite to the corresponding exhaust hole 111. After the annular rib 223 is inserted into the exhaust hole 111, the plastic plate 22 is completely put into the box.

[0087] In an optional embodiment, if Figure 7 As shown, two glue blocking beams 16 are arranged in the box body 11 along the length direction thereof, and the two glue blocking beams 16 and the side wall of the box body 11 jointly define a first accommodating cavity 116, the battery module 20 is arranged in the first accommodating cavity 116, and the structural glue 17 is filled in the first accommodating cavity 116. When the structural glue 17 is poured into the bottom of the battery cell 21, it is sufficient to ensure that the structural glue 17 is flush with the glue blocking beam 16. At this time, the height of the structural glue 17 is about 10 mm, so that the battery cell 21 can be fixed and the waste of glue can be avoided.

[0088] In an optional embodiment, if Figure 2As shown, the battery cell 21 has a positive electrode 211 and a negative electrode 212, and the positive electrode 211 and the negative electrode 212 are located at the same end of the battery cell 21 in the axial direction, wherein the positive electrode 211 is a circular end face with a smaller area at the top end of the battery cell 21, and the negative electrode 212 is an annular end face with a larger area at the top end of the battery cell 21, and the positive electrode 211 is higher than the negative electrode 212.

[0089] In an optional embodiment, if Figure 2 and Fig.13 As shown, the battery pack also includes a CSS component 40, which includes a bracket 41 and a plurality of busbars 42. The bracket 41 may be made of plastic, and the busbar 42 may be a copper busbar or an aluminum busbar. The bracket 41 abuts against a plurality of battery cells 21, and the busbar 42 is used to electrically connect the positive electrode 211 and the negative electrode 212 of two adjacent battery cells 21. The bracket 41 is provided with a plurality of heat riveting posts 411 corresponding to the busbars 42 one by one, and the busbars 42 are provided with through holes. The heat riveting posts 411 are configured to pass through the through holes and then be heat riveted to fix the busbars 42 on the bracket 41. This arrangement enables the heat riveting posts 411 to have sufficient connection strength and high stability after heat riveting the busbars 42.

[0090] Combination Figure 2 and Fig.13 In this embodiment, taking 12 battery cells 21 as an example, the busbars 42 are set to 13. The 13 busbars 42 include 11 intermediate series busbars 421 and 2 output series busbars 422. The intermediate series busbars 421 are used to connect two adjacent battery cells 21 in series, and the output series busbars 422 serve as the output end after the 12 battery cells 21 are connected in series. The intermediate busbar 42 includes a positive electrode portion 4211 and a negative electrode portion 4212 connected to each other. The lower surface of the positive electrode portion 4211 abuts against the positive electrode 211 of one of the battery cells 21, and the lower surface of the negative electrode portion 4212 abuts against the negative electrode 212 of the adjacent battery cell 21. Subsequently, the positive electrode portion 4211 can be fixed to the positive electrode 211 of the battery cell 21, and the negative electrode portion 4212 can be fixed to the negative electrode 212 of the adjacent battery cell 21 by welding, so as to realize the series connection of two adjacent battery cells 21. A first circular hole 4213 is formed on the positive electrode portion 4211 , and the first circular hole 4213 is used for being aligned with the positive electrode 211 of the battery cell 21 for welding.

[0091] One of the output series rows 422 is constructed in the form of a positive electrode portion 4211, which is used to connect to the positive electrode 211 of the first-end battery cell 21, and the output series row 422 extends outward to form a negative electrode output terminal 4222. The other output series row 422 is constructed in the form of a negative electrode portion 4212, which is used to connect to the negative electrode 212 of the terminal battery cell 21, and the output series row 422 extends outward to form a positive electrode output terminal 4221.

[0092] In an optional embodiment, if Figure 2 and Figure 7As shown, a second accommodating cavity 117 is further provided in the box body 11, and the second accommodating cavity 117 is arranged adjacent to the first accommodating cavity 116. The battery pack also includes a BMS module 50, and the BMS module 50 is arranged in the second accommodating cavity 117 to be arranged adjacent to the battery module 20. The BMS module 50 is electrically connected to the battery module 20 to perform intelligent management and maintenance on the battery module 20.

[0093] In an optional embodiment, if Fig.13 , Fig.14 and Fig.17 As shown, the BMS module 50 includes a first positive stud 51 and a first negative stud 52 arranged at the top thereof, two output series rows 422 are arranged adjacent to the BMS module 50, that is, the positive output terminal 4221 and the negative output terminal 4222 are arranged adjacent to the BMS module 50, the first positive stud 51 is penetrated through the positive output terminal 4221, and the first negative stud 52 is penetrated through the negative output terminal 4222, thereby realizing the electrical connection between the BMS module 50 and the battery module 20. Among them, a second circular hole 4223 is provided on the positive output terminal 4221 and the negative output terminal 4222, the second circular hole 4223 on the positive output terminal 4221 is used to cooperate with the first positive stud 51, and the second circular hole 4223 on the negative output terminal 4222 is used to cooperate with the first negative stud 52, and then the nuts 58 (reference) are screwed on the first positive stud 51 and the first negative stud 52 respectively. Figure 2 ), thereby achieving a stable electrical connection.

[0094] Through the above arrangement, multiple bus bars 42 can be connected in series between the battery cells 21 through a certain loop, and finally directly connected to the BMS module 50 through the positive output terminal 4221 and the negative output terminal 4222 at one end close to the BMS module 50, which can reduce the problem of cross-connected copper bars of square shell battery cells and simplify the electrical connection structure.

[0095] In an optional embodiment, if Figures 14 to 17As shown, the BMS module 50 also includes a second positive stud 53 and a second negative stud 54. The second positive stud 53 and the first positive stud 51 are electrically connected through the copper bar inside the BMS module 50, and the second negative stud 54 and the first negative stud 52 are electrically connected through the copper bar inside the BMS module 50. Two output copper bars 32 are embedded on the inner side of the upper cover 30, which are respectively a positive copper bar and a negative copper bar. The positions of the two output copper bars 32 correspond to the second positive stud 53 and the second negative stud 54. The second positive stud 53 is inserted into one of the output copper bars 32, and the second negative stud 54 is inserted into the other output copper bar 32. Finally, the corresponding nuts 58 are screwed on the second positive stud 53 and the second negative stud 54 to achieve stable electrical connection. Each output copper bar 32 is provided with an output stud 321, which extends to the outside of the upper cover 30 to achieve the output of current and voltage.

[0096] In the actual assembly process, the nut 58 can be installed on the second positive stud 53 and the second negative stud 54 and tightened after the upper cover 30 is assembled to achieve the conduction of the entire circuit. Therefore, in order to facilitate the external installation and screwing of the nut 58, an optional embodiment, such as Fig.15 As shown, the upper cover 30 is provided with reserved holes 35 at positions corresponding to the second positive stud 53 and the second negative stud 54. After the upper cover 30 and the lower box body 10 are assembled, the nuts 58 are installed on the second positive stud 53 and the second negative stud 54 through the corresponding reserved holes 35 and tightened. After the nuts 58 are tightened, as shown in FIG. Fig.16 As shown, a plastic plug 36 is installed in each reserved hole 35 to seal the reserved hole 35 , and the plastic plug 36 is fixed by laser penetration welding to form a final sealed inner cavity.

[0097] In an optional embodiment, if Figure 2 , Figure 7 and Fig.14 As shown, L-shaped mounting feet 57 are respectively provided at the four corners of the bottom of the BMS module 50, and four mounting studs 118 are integrally formed at the bottom of the second accommodating cavity 117 of the box body 11. When installing the BMS module 50, each mounting stud 118 is passed through the corresponding mounting foot 57, and then a nut 58 is tightened on each mounting stud 118, so as to fix the BMS module 50 in the second accommodating cavity 117.

[0098] In an optional embodiment, if Figure 2 and Fig.17As shown, the battery pack also includes a PCB board 60, which is located on the upper side of the CSS component 40. A collection connector 61 and a plurality of collection nickel sheets 62 are integrated on the PCB board 60. The collection connector 61 is located on the side of the PCB board 60 close to the BMS module 50. The plurality of collection nickel sheets 62 are arranged in a one-to-one correspondence with the plurality of bus bars 42. Each collection nickel sheet 62 is welded and fixed to the corresponding bus bar 42 to electrically connect the PCB board 60 and the CSS component 40, thereby realizing the voltage and temperature collection function.

[0099] In an optional embodiment, if Figure 2 , Fig.14 and Fig.17 As shown, the battery pack also includes a wiring harness assembly 90, which includes a first wiring harness 91 and a second wiring harness 92. The BMS module 50 is also provided with a first acquisition socket 55 and a second acquisition socket 56. One end of the second wiring harness 92 is plugged into the acquisition plug-in 61 on the PCB board 60, and the other end of the second wiring harness 92 is plugged into the second acquisition socket 56 on the BMS module 50, thereby realizing the electrical connection between the PCB board 60 and the BMS module 50. Fig.16 As shown, the upper cover 30 is provided with an assembly socket 33 for plugging in an external connector, one end of the first wiring harness 91 is plugged into the first acquisition socket 55 on the BMS module 50, and the other end of the first wiring harness 91 extends into the assembly socket 33 to be electrically connected to an external device to realize voltage and temperature acquisition. The above electrical connection structure has a compact and reasonable layout and can save space.

[0100] In an optional embodiment, if Figure 2 and Fig.18 As shown, the battery pack also includes a liquid cooling plate 70, which is arranged on the top of the battery module 20, specifically on the upper side of the PCB board 60, and a thermal conductive glue 73 is provided between the liquid cooling plate 70 and the PCB board 60, and two straight tubes 74 are provided on the liquid cooling plate 70 for liquid inlet and liquid outlet, respectively, and both straight tubes 74 extend to the outside of the upper cover 30. The coolant enters the liquid cooling plate 70 through one of the straight tubes 74, and takes away the heat of the battery module 20 by flowing in the liquid cooling plate 70, and finally flows out from the other straight tube 74, thereby realizing the circulation of the coolant, thereby cooling the battery module 20. The thickness of the thermal conductive glue 73 is about 1 mm, which is used to conduct heat and further improve the heat dissipation efficiency. Since the liquid cooling plate 70 is arranged on the upper side of the battery module 20, the heat dissipation performance is best in the axial direction of the battery cell 21.

[0101] In an optional embodiment, if Fig.18As shown, the liquid cooling plate 70 includes a stamped plate 71 and a flat plate 72, wherein the flat plate 72 is connected to the stamped plate 71 to form a closed liquid cooling channel, wherein the flat plate 72 and the stamped plate 71 are fixed together by brazing, and the liquid cooling channel is tortuous and is used for the flow of coolant to improve the heat dissipation effect of the battery module 20.

[0102] In an optional embodiment, if Fig.18 As shown, the flat plate 72 is connected to the side of the stamped plate 71 close to the battery module 20, the flat plate 72 is in contact with the thermally conductive adhesive 73, and the straight tube 74 is welded and fixed to the stamped plate 71. Since the liquid cooling channel is formed on the stamped plate 71, the surface of the stamped plate 71 is uneven. Compared with the arrangement of the flat plate 72 on top and the stamped plate 71 on the bottom, the arrangement of the stamped plate 71 on top and the flat plate 72 on the bottom in this embodiment makes the flat plate 72 contact with the thermally conductive adhesive 73, increases the contact area with the thermally conductive adhesive 73, and improves the heat conduction effect and heat dissipation efficiency.

[0103] In an optional embodiment, if Fig.16 As shown, the upper cover 30 is provided with two recessed portions 34, and the two straight tubes 74 are respectively located in the corresponding recessed portions 34. This arrangement can prevent the straight tubes 74 from protruding from the upper surface of the upper cover 30, thereby reducing the overall height of the battery pack and reducing the space occupied.

[0104] In an optional embodiment, if Fig.19 As shown, each straight tube 74 is provided with a flange 75, and the flange 75 is located on the inner side of the upper cover 30. The flange 75 is provided with a first sealing groove 751 arranged around the straight tube 74, and a second sealing groove 752 and a connecting hole 753 arranged in a stepped shape. The second sealing groove 752 and the connecting hole 753 are connected to form a stepped hole. There are two stepped holes, and the two second sealing grooves 752 are symmetrically arranged relative to the straight tube 74, and the two connecting holes 753 are symmetrically arranged relative to the straight tube 74. Figure 1 and Fig. 20 As shown, the battery pack further includes a sealing assembly 80, which includes a first sealing ring 81, a second sealing ring 82, a pressing plate 83 and a fastener 84. The first sealing ring 81 is accommodated in the first sealing groove 751, the second sealing ring 82 is accommodated in the second sealing groove 752, the pressing plate 83 is made of metal, the pressing plate 83 is located on the outside of the upper cover 30 and is sleeved on the straight tube 74, and the fastener 84 passes through the pressing plate 83 and the upper cover 30 in sequence and is connected with the connecting hole 753. Among them, the connecting hole 753 is a threaded hole, and the fastener 84 is a screw with a flat spring washer.

[0105] During installation, first install the first sealing ring 81 into the first sealing groove 751, install the second sealing ring 82 into the second sealing groove 752, and then assemble the upper cover 30 on the lower box body 10 and seal and fix it with the sealant 15. During the assembly of the upper cover 30, the free end of the straight tube 74 is passed through the outside of the upper cover 30, and then the pressure plate 83 is sleeved on the straight tube 74 and pressed against the upper cover 30. Finally, the fastener 84 is passed through the pressure plate 83 and the upper cover 30 in turn and then threadedly connected to the connecting hole 753, thereby finally achieving the fixation of the straight tube 74 and the sealing of the connection.

[0106] The assembly process of the battery pack is as follows:

[0107] 1) Install the plastic plate 22 into the first accommodating cavity 116 of the lower box 10, then place each battery cell 21 into the corresponding mounting groove 221 on the plastic plate 22, and then pour structural glue 17 into the bottom of the battery cell 21 to fix the battery cell 21 and the plastic plate 22 in the lower box 10;

[0108] 2) Fix the BMS module 50 into the second accommodating cavity 117 of the lower box 10, install the CSS assembly 40, match each bus 42 with the corresponding battery cell 21 to form a series circuit, and then match the first positive stud 51 of the BMS module 50 with the positive output terminal 4221 of the bus 42, and match the first negative stud 52 of the BMS module 50 with the negative output terminal 4222 of the bus 42 to achieve electrical connection between the BMS module 50 and the battery module 20;

[0109] 3) Weld and fix the current collection nickel sheet 62 of the PCB board 60 to the corresponding bus bar 42 to realize the electrical connection between the PCB board 60 and the CSS assembly 40, and then respectively plug the second wiring harness 92 into the current collection connector 61 on the PCB board 60 and the second current collection socket 56 on the BMS module 50, and plug one end of the first wiring harness 91 into the first current collection socket 55 on the BMS module 50;

[0110] 4) Apply thermal conductive adhesive 73 on the upper side of PCB board 60, and then install liquid cooling plate 70, which presses down thermal conductive adhesive 73 to make its thickness uniform;

[0111] 5) Apply sealant 15 in the glue groove 113 until the sealant 15 fills about two-thirds of the height of the glue groove 113, then install the first sealing ring 81 into the first sealing groove 751, and install the second sealing ring 82 into the second sealing groove 752;

[0112] 6) Assemble the upper cover 30. During the assembly process, the other end of the first wiring harness 91 is plugged into the assembly socket 33 of the upper cover 30. At the same time, the corresponding output studs 321 are respectively matched with the second positive studs 53 and the second negative studs 54. At the same time, the free end of the straight tube 74 is passed through the outside of the upper cover 30. Then, the positioning rib 31 at the bottom of the upper cover 30 is inserted into the glue groove 113 to squeeze the sealant 15, so as to achieve sealing and fixation between the upper cover 30 and the lower box body 10;

[0113] 7) The pressing plate 83 is sleeved on the straight tube 74 and pressed against the upper cover 30, and then the fastener 84 is passed through the pressing plate 83 and the upper cover 30 in sequence and threadedly connected to the connecting hole 753 to achieve the fixing of the straight tube 74 and the sealing of the connection;

[0114] 8) Install the nut 58 on the second positive electrode stud 53 and the second negative electrode stud 54 through the corresponding reserved holes 35 and tighten them, and then install the plastic plug 36 in each reserved hole 35 by laser through-welding to form the final sealed inner cavity;

[0115] 9) An explosion-proof valve 14 is installed on the side of the lower box body 10 to form a closed exhaust passage 13.

[0116] This embodiment also provides an electric device, including the above-mentioned battery pack, which can provide electric energy for the electric device. The electric device can be an electric vehicle, a hybrid electric vehicle, or a ship. In other embodiments, the electric device can also be other equipment, which is not specifically limited here. The electric device provided in this embodiment can ensure the safety performance of the electric device by setting the above-mentioned battery pack.

[0117] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. A battery pack, characterized in that: include: The lower box body (10) comprises a box body (11) and a bottom plate (12), wherein the bottom plate (12) is connected to the bottom end of the box body (11) and defines an exhaust passage (13) with the box body (11), an explosion-proof valve (14) for connecting the exhaust passage (13) and the outside of the lower box body (10) is provided on the side of the box body (11), and a plurality of exhaust holes (111) connected to the exhaust passage (13) are provided on the bottom surface of the box body (11); A battery module (20) comprising a plurality of battery cells (21) arranged inside the box body (11), wherein the pressure relief valve of each battery cell (21) is arranged in one-to-one correspondence with the exhaust hole (111); The upper cover (30) is buckled on the top of the box body (11), and the upper cover (30) and the box body (11) are sealed and fixed by a sealant (15).

2. The battery pack according to claim 1, characterized in that: The bottom end of the box body (11) is provided with a positioning groove (112) matching the contour of the bottom plate (12); the bottom plate (12) is accommodated in the positioning groove (112) and is welded and fixed to the bottom end of the box body (11).

3. The battery pack according to claim 1, characterized in that: The top of the box body (11) is provided with a glue groove (113), and the glue groove (113) is used to fill the sealant (15). The bottom edge of the upper cover (30) is provided with a positioning rib (31) that matches the glue groove (113).

4. The battery pack according to claim 1, characterized in that: The battery module (20) further comprises a plastic plate (22) for supporting the plurality of battery cells (21); a plurality of mounting grooves (221) are provided on one side of the plastic plate (22); one end of each battery cell (21) on which the pressure relief valve is mounted is accommodated in a corresponding mounting groove (221); a pressure relief hole (222) is provided at the bottom of each mounting groove (221); and a portion of the pressure relief hole (222) is located in the corresponding exhaust hole (111).

5. The battery pack according to claim 4, characterized in that: An annular convex rib (223) is protruded from the edge of one end of each of the pressure relief holes (222) away from the battery core (21), and each of the annular convex ribs (223) is inserted into the corresponding exhaust hole (111); And / or the plastic plate (22) is provided with a plurality of weight-reducing holes (224) arranged at intervals.

6. The battery pack according to claim 4, characterized in that: A positioning hole (225) is provided on one of the plastic plate (22) and the bottom surface of the box body (11), and a first positioning pin (114) is provided on the other of the two to be plugged into and matched with the positioning hole (225); and / or A positioning groove (226) is provided on one of the peripheral side of the plastic plate (22) and the peripheral side of the box body (11), and a second positioning pin (115) pluggably matched with the positioning groove (226) is provided on the other of the two.

7. The battery pack according to any one of claims 1 to 6, characterized in that: Two rubber blocking beams (16) are arranged in the box body (11) at intervals along its length direction, and the two rubber blocking beams (16) and the side wall of the box body (11) together define a first accommodating cavity (116), the battery module (20) is arranged in the first accommodating cavity (116), and the first accommodating cavity (116) is filled with structural glue (17).

8. The battery pack according to any one of claims 1 to 6, characterized in that: The battery pack further comprises a CSS assembly (40), wherein the CSS assembly (40) comprises a bracket (41) and a plurality of busbars (42), wherein the bracket (41) is covered on the plurality of battery cells (21), and the busbars (42) are used to electrically connect the positive electrodes (211) and the negative electrodes (212) of two adjacent battery cells (21); The bracket (41) is provided with a plurality of heat-riveting columns (411) corresponding one to one with the busbar (42); the busbar (42) is provided with a through hole; the heat-riveting columns (411) are configured to pass through the through hole and then be heat-riveted to fix the busbar (42) on the bracket (41).

9. The battery pack according to claim 8, characterized in that: The battery pack further comprises a BMS module (50) arranged in the box body (11) and located beside the battery module (20), wherein the BMS module (50) comprises a first positive electrode stud (51) and a first negative electrode stud (52) arranged at a top end thereof; The plurality of busbars (42) include two output series busbars (422), the two output series busbars (422) are arranged adjacent to the BMS module (50), one of the output series busbars (422) is provided with a positive output terminal (4221), the other of the output series busbars (422) is provided with a negative output terminal (4222), the first positive stud (51) is passed through the positive output terminal (4221), and the first negative stud (52) is passed through the negative output terminal (4222).

10. The battery pack according to any one of claims 1 to 6, characterized in that: The battery pack further comprises a liquid cooling plate (70), the liquid cooling plate (70) being arranged on the top of the battery module (20), and a heat conductive adhesive (73) being arranged between the liquid cooling plate (70) and the battery module (20), and the liquid cooling plate (70) being provided with two straight tubes (74) for liquid inlet and liquid outlet, respectively, and the two straight tubes (74) both extend to the outside of the upper cover (30).

11. The battery pack according to claim 10, characterized in that: The liquid cooling plate (70) comprises a stamped plate (71) and a flat plate (72), wherein the flat plate (72) is connected to a side of the stamped plate (71) close to the battery module (20) to form a closed liquid cooling channel, the flat plate (72) is in close contact with the thermal conductive adhesive (73), and the straight tube (74) is connected to the stamped plate (71).

12. The battery pack according to claim 10, characterized in that: The upper cover (30) is provided with two recessed portions (34), and the two straight tubes (74) are respectively located in the corresponding recessed portions (34).

13. The battery pack according to claim 10, characterized in that: Each straight tube (74) is provided with a flange (75) in an annular manner, and the flange (75) is located on the inner side of the upper cover (30), and the flange (75) is provided with a first sealing groove (751) arranged around the straight tube (74), a second sealing groove (752) arranged in a stepped shape, and a connecting hole (753); The battery pack also includes a sealing assembly (80), and the sealing assembly (80) includes a first sealing ring (81), a second sealing ring (82), a pressure plate (83) and a fastener (84). The first sealing ring (81) is accommodated in the first sealing groove (751), and the second sealing ring (82) is accommodated in the second sealing groove (752). The pressure plate (83) is located on the outer side of the upper cover (30) and is sleeved on the straight tube (74). The fastener (84) passes through the pressure plate (83) and the upper cover (30) in sequence and then cooperates with the connecting hole (753) to be connected.

14. An electrical device, characterized in that: Comprising a battery pack as claimed in any one of claims 1 to 13.

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