Battery module

Abstract

The application provides a battery module, comprising a battery cell assembly and a fire extinguishing device, the battery cell assembly comprises a plurality of battery cell frames and a plurality of battery cells, the plurality of battery cell frames are arranged in sequence along the length direction of the battery module, and at least part of the battery cell frames are provided with at least one battery cell; each battery cell frame is provided with a fire extinguishing groove, the fire extinguishing grooves on the plurality of battery cell frames are communicated with each other to form a fire extinguishing channel, and the fire extinguishing device is arranged in the fire extinguishing channel; the fire extinguishing grooves extend along the length direction of the battery module and penetrate the battery cell frames, the fire extinguishing channel extends along the length direction of the battery module, and the fire extinguishing device extends along the length direction of the battery module in the fire extinguishing channel. The battery module provided by the application is not only compact in structure, convenient to assemble, but also high in fire extinguishing efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of batteries, in particular to a battery module. BACKGROUND

[0002] With the development of electronic technology, lithium ion batteries have been widely used due to their high specific power, long cycle life, good safety performance and no pollution. Thermal runaway is an important concern in the design of lithium ion batteries. When a battery experiences thermal runaway, it can cause high temperature, smoke, fire and even explosion in a short time, which is extremely dangerous.

[0003] As provided in a battery module with automatic fire extinguishing of Chinese patent No. CN112201884A, it contains a plurality of battery cells, a heat dissipation part connected with the battery cells, and a pipeline connected with the heat dissipation part and easy to break in fire. The pipeline circulates cooling liquid for extinguishing fire. The defects of this scheme are: the pipeline for extinguishing fire is suspended outside the shell for accommodating a plurality of battery cells, the pipeline lacks protection and is easy to be damaged under pressure, and the pipeline needs to occupy additional space, increasing the outer size of the battery module and making the structure of the battery module not compact enough.

[0004] As provided in a battery module with automatic fire extinguishing of Chinese patent No. CN110797476A, it includes a frame and battery cells arranged in the frame. Each frame is provided with a storage room for storing fire extinguishing agent. The advantages of this scheme are: a random number of frames flexibly form a battery module, the fire extinguishing agent is arranged in the frame, the structure is compact, and the fire extinguishing agent can be protected. However, the defects of this scheme are: each storage room is independent, and the fire extinguishing agent needs to be arranged in each storage room one by one, which is complicated to operate.

[0005] Therefore, it is necessary to design a battery module with compact structure, easy assembly and automatic fire extinguishing. SUMMARY

[0006] The purpose of the present application is to provide a battery module which not only has compact structure and easy assembly, but also has high fire extinguishing efficiency.

[0007] The application provides a battery module, which comprises an electric cell assembly and a fire extinguishing device, the electric cell assembly comprises a plurality of electric cell frames and a plurality of electric cells, the plurality of electric cell frames are arranged in sequence along the length direction of the battery module, and at least part of the electric cell frames are provided with at least one electric cell; each electric cell frame is provided with a fire extinguishing groove, the fire extinguishing grooves on the plurality of electric cell frames are communicated with each other to form a fire extinguishing channel, and the fire extinguishing device is arranged in the fire extinguishing channel; the fire extinguishing grooves extend along the length direction of the battery module and penetrate through the electric cell frames, the fire extinguishing channel extends along the length direction of the battery module, and the fire extinguishing device extends along the length direction of the battery module in the fire extinguishing channel.

[0008] In an implementable mode, the fire extinguishing groove is arranged on the outer wall of the electric cell frame.

[0009] In an implementable mode, the fire extinguishing device is provided with a first fire extinguishing material, and when the temperature of the fire extinguishing device reaches the melting point, the fire extinguishing device can be broken to release the first fire extinguishing material in the fire extinguishing device.

[0010] In an implementable mode, the electric cell is provided with a tab, and the fire extinguishing groove is arranged on the electric cell frame on the side corresponding to the tab of the electric cell.

[0011] In an implementable mode, the electric cell frame comprises a cover plate, the cover plate is arranged on the side corresponding to the tab of the electric cell, and the fire extinguishing groove is arranged on the cover plate.

[0012] In an implementable mode, the cover plate is provided with a through hole for the tab of the electric cell to pass through.

[0013] In an implementable mode, the electric cell is provided with two tabs on the same side, and the two tabs are arranged at intervals; the cover plate is arranged on the side corresponding to the tab of the electric cell, the cover plate is provided with two through holes corresponding to the two tabs respectively, and the fire extinguishing groove is arranged between the two through holes; and / or, the fire extinguishing groove is arranged on the outer side of the two through holes (that is, the fire extinguishing groove is not arranged between the two through holes, in other words, in the length direction of the cover plate, the fire extinguishing groove is arranged on one side or both sides of the two through holes).

[0014] In an implementable mode, the electric cell frame further comprises a heat-conducting frame connected to the cover plate, the heat-conducting frame is located on one side of the cover plate, the heat-conducting frame is provided with an electric cell mounting groove, and the electric cell is arranged in the electric cell mounting groove.

[0015] In an implementable mode, the heat-conducting frame is provided with a first cable tie mounting groove for mounting a cable tie.

[0016] In an implementation, the heat-conducting frame is provided with a first step portion formed by concave forming of an outer wall of the heat-conducting frame, and the first cable tie mounting groove is arranged on the outer wall of the heat-conducting frame and corresponds to the position of the first step portion.

[0017] In an implementation, the battery cell is provided with two tab ears arranged on opposite sides, the cell frame includes two cover plates arranged on opposite sides of the battery cell respectively, and the two cover plates correspond to the two tab ears of the battery cell respectively, each cover plate is provided with a through hole, and the fire extinguishing groove is arranged on one side or opposite sides of the through hole.

[0018] In an implementation, the battery module further includes a bus bar arranged on a side of the cover plate away from the battery cell, the bus bar is provided with a tab ear groove for the tab ear of the battery cell to pass through, and the tab ear of the battery cell is electrically connected to the bus bar after sequentially passing through the through hole and the tab ear groove.

[0019] In an implementation, the bottom wall of the fire extinguishing groove is provided with a second cable tie mounting groove for mounting a cable tie.

[0020] In an implementation, the cell frame is provided with a flow guide hole at a position corresponding to the fire extinguishing groove, and heat generated after thermal runaway of the battery cell can enter the fire extinguishing groove through the flow guide hole.

[0021] In an implementation, the second cable tie mounting groove is formed by concave forming of a part of the bottom wall of the fire extinguishing groove, a part of the bottom wall of the fire extinguishing groove not concave forms a second step portion, and the flow guide hole is arranged on the second step portion.

[0022] In an implementation, the fire extinguishing member is arranged corresponding to the second cable tie mounting groove, and the fire extinguishing member does not completely cover the flow guide hole.

[0023] In an implementation, at least part of the cell frame is provided with a plurality of battery cells arranged sequentially in the cell frame, a heat insulation pad and a tab ear edge isolation strip are arranged between adjacent battery cells, and the tab ear edge isolation strip is arranged corresponding to the position of the tab ear of the battery cell.

[0024] In an implementation, the tab ear edge isolation strip is provided with a second fire extinguishing material, and when the temperature of the tab ear edge isolation strip reaches the melting point, the tab ear edge isolation strip can be broken to release the second fire extinguishing material in the tab ear edge isolation strip.

[0025] In an implementable mode, opposite sides of the cell frame along the length direction of the battery module are respectively provided with positioning pins and positioning holes; the positioning pin on one of the adjacent two cell frames can be inserted into the positioning hole on the other cell frame to realize the connection between the adjacent two cell frames.

[0026] In an implementable mode, the battery module further comprises a protective plate, which is arranged on the side of the cell assembly corresponding to the fire extinguishing device; the protective plate is provided with an opening at the position corresponding to the fire extinguishing device.

[0027] In an implementable mode, the fire extinguishing device is in a long strip structure, and the fire extinguishing device extends from one end of the fire extinguishing channel to the opposite end of the fire extinguishing channel.

[0028] In an implementable mode, the battery module further comprises end plates and a cable tie, the end plates are arranged at opposite ends of the cell assembly along the length direction of the battery module; the cable tie is arranged around the cell assembly and the end plates, and the cable tie binds the cell assembly and the end plates together.

[0029] The battery module provided by the application reduces the influence of the arrangement of the fire extinguishing device on the outer size of the battery module, improves the compactness of the structure of the battery module, and protects the fire extinguishing device from being damaged by pressure. At the same time, since the fire extinguishing channel is composed of the fire extinguishing grooves on the plurality of cell frames, when a cell in a certain position of the cell assembly catches fire, the fire extinguishing device can respond in time to extinguish the fire, i.e. the fire extinguishing range of the fire extinguishing device covers the entire cell assembly, so the utilization rate of the fire extinguishing device is high, and the fire extinguishing efficiency is high. Moreover, during assembly, the fire extinguishing device only needs to be arranged in the fire extinguishing channel once, without the need to arrange the fire extinguishing device for each cell frame separately. Furthermore, since the fire extinguishing device is arranged in the fire extinguishing channel along the length direction of the battery module, the number of fire extinguishing devices can be reduced, thereby improving the assembly efficiency of the battery module. The battery module not only has a compact structure and is easy to assemble, but also has high fire extinguishing efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 FIG. 1 is a schematic diagram of the three-dimensional structure of the battery module in the embodiment of the application.

[0031] Figure 2 FIG. 7 is a schematic diagram of the exploded structure of the battery module. Figure 1

[0032] Figure 3 Figure 2 ​​The exploded structural schematic view of the middle battery cell assembly.

[0033] Figure 4 The exploded structural schematic view of the middle battery cell and the battery cell frame. Figure 3 The exploded structural schematic view of the middle battery cell and the battery cell frame.

[0034] Figure 5 The exploded structural schematic view of the middle battery cell and the battery cell frame. Figure 4 The exploded structural schematic view of the middle battery cell and the battery cell frame.

[0035] Figure 6 The exploded structural schematic view of the middle battery cell and the battery cell frame. Figure 5 The exploded structural schematic view of the middle battery cell and the battery cell frame.

[0036] Figure 7 The exploded structural schematic view of the middle battery cell and the battery cell frame. Figure 6 The exploded structural schematic view of the middle battery cell and the battery cell frame.

[0037] Figure 8 The exploded structural schematic view of the middle battery cell and the battery cell frame. Figure 7 The exploded structural schematic view of the middle battery cell and the battery cell frame.

[0038] Figure 9 The exploded structural schematic view of the middle battery cell and the battery cell frame. The exploded structural schematic view of the middle battery cell and the battery cell frame.

[0039] The exploded structural schematic view of the middle battery cell and the battery cell frame. Figure 10 The exploded structural schematic view of the middle battery cell and the battery cell frame. Figure 9 The exploded structural schematic view of the middle battery cell and the battery cell frame.

[0040] Figure 11 The exploded structural schematic view of the middle battery cell and the battery cell frame.

[0041] Figure 12 The exploded structural schematic view of the middle battery cell and the battery cell frame. DETAILED DESCRIPTION

[0042] The specific embodiments of the present application will be further described in conjunction with the drawings and examples. The following examples are used to illustrate the present application, but are not used to limit the scope of the present application.

[0043] The terms "first", "second", "third", "fourth" and the like in the description and claims of the present application (if any) are used for distinguishing between similar objects talking about the technical scheme and not necessarily used to describe a particular sequential or chronological order.

[0044] The terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", and the like (if any) in the description and claims of the present application are defined with reference to the positions of the structures in the drawings and the positions of the structures relative to each other, only to express the technical scheme clearly and conveniently. It should be understood that the use of the terms should not limit the scope of the present application.

[0045] As Figures 1 to 8As shown, the battery module provided by the embodiment of the present application comprises a battery cell assembly 100 and a fire extinguishing device 3. The battery cell assembly 100 comprises a plurality of battery cell frames 1 and a plurality of battery cells 2. The plurality of battery cell frames 1 are arranged in sequence along the length direction L of the battery module. At least part of the battery cell frames 1 is provided with at least one battery cell 2 (i.e. all the battery cell frames 1 are provided with one or more battery cells 2, or part of the battery cell frames 1 can also be provided without battery cells 2). Each battery cell frame 1 is provided with a fire extinguishing groove 111. The positions of the fire extinguishing grooves 111 on the plurality of battery cell frames 1 correspond to each other (i.e. the fire extinguishing grooves 111 on the plurality of battery cell frames 1 are arranged at the same position on each battery cell frame 1). The fire extinguishing grooves 111 at the same position on each battery cell frame 1 are in communication with each other to form a fire extinguishing channel 110. The fire extinguishing device 3 is arranged in the fire extinguishing channel 110.

[0046] Specifically, the battery module provided by the embodiment reduces the influence of the arrangement of the fire extinguishing device 3 on the external size of the battery module, improves the compactness of the structure of the battery module, and protects the fire extinguishing device 3 from being damaged by pressure due to the arrangement of the fire extinguishing device 3 in the fire extinguishing channel 110. At the same time, since the fire extinguishing channel 110 is composed of the fire extinguishing grooves 111 on the plurality of battery cell frames 1 in communication with each other, when a battery cell 2 at a certain position in the battery cell assembly 100 catches fire, the fire extinguishing device 3 in the fire extinguishing channel 110 can respond in time to extinguish the fire, i.e. the fire extinguishing range of the fire extinguishing device 3 in the fire extinguishing channel 110 covers the entire battery cell assembly 100, so that the utilization rate of the fire extinguishing device 3 is high and the fire extinguishing efficiency is high. Moreover, during assembly, the fire extinguishing device 3 only needs to be arranged in the fire extinguishing channel 110 once, without the need to arrange the fire extinguishing device 3 for each battery cell frame 1 separately, thereby facilitating the assembly efficiency of the battery module. The battery module not only has a compact structure and is easy to assemble, but also has high fire extinguishing efficiency.

[0047] As shown in the figures, Figure 4 As an implementation form, the fire extinguishing groove 111 is arranged on the outer wall of the battery cell frame 1.

[0048] As shown in the figures, Figure 1 , Figure 2 and Figure 4As shown, as an embodiment, the fire extinguishing groove 111 is arranged along the length direction L of the battery module and penetrates the battery cell frame 1, and the fire extinguishing channel 110 is arranged along the length direction L of the battery module; the fire extinguishing member 3 is in a long strip structure, and is arranged in the fire extinguishing channel 110 along the length direction L of the battery module, and extends from one end of the fire extinguishing channel 110 to the opposite end of the fire extinguishing channel 110, that is, the fire extinguishing member 3 is a whole long strip structure. Of course, in other embodiments, a plurality of fire extinguishing members 3 can be arranged in the fire extinguishing channel 110 in a head-to-tail manner. The fire extinguishing member 3 can be fixed in the fire extinguishing channel 110 by bonding or binding with a strap.

[0049] As an embodiment, the fire extinguishing member 3 is provided with a first fire extinguishing material, and when the temperature of the fire extinguishing member 3 reaches the melting point, the fire extinguishing member 3 can break to release the first fire extinguishing material in the fire extinguishing member 3. Specifically, the fire extinguishing member 3 includes a low-melting-point tube shell and a first fire extinguishing material arranged in the tube shell. The tube shell can be made of a material with a corresponding melting point according to the corresponding thermal runaway temperature. The first fire extinguishing material can be a phase change material with fire extinguishing function, such as halogenated alkane, specifically perfluorohexanone, etc. When the thermal runaway reaches the trigger temperature of the fire extinguishing member 3, the fire extinguishing member 3 breaks to release the first fire extinguishing material in the fire extinguishing member 3, thereby timely cooling and extinguishing the battery cell 2 that has thermal runaway.

[0050] Of course, in other embodiments, the fire extinguishing member 3 can also be a cooling pipeline, and the cooling pipeline circulates cooling liquid. When the temperature of the cooling pipeline reaches the melting point, the cooling pipeline can break to release the cooling liquid in the cooling pipeline, thereby extinguishing and cooling the battery cell 2 that has thermal runaway.

[0051] As shown in Figure 3 , Figure 4 and Figure 5 , as an embodiment, a plurality of battery cells 2 are arranged along the length direction L of the battery module, and the battery cell 2 is provided with a tab 21, and the fire extinguishing groove 111 is arranged on the battery cell frame 1 on the side corresponding to the tab 21 of the battery cell 2, that is, the fire extinguishing member 3 is also arranged on the side of the tab 21 of the battery cell 2. When the battery cell 2 has thermal runaway, the fire extinguishing member 3 can timely cool and extinguish the tab 21 position of the battery cell 2 prone to thermal runaway, so as to improve the extinguishing efficiency.

[0052] As shown in Figure 4 and Figure 6 , as an embodiment, the battery cell frame 1 includes a cover plate 11, and the cover plate 11 is arranged on the side corresponding to the tab 21 of the battery cell 2, and the fire extinguishing groove 111 is arranged on the cover plate 11.

[0053] As shown in Figure 2 and Figure 4As shown, as an embodiment, the fire extinguishing groove 111 penetrates the cover plate 11 along the thickness direction of the battery cell 2, so that the fire extinguishing grooves 111 on the cover plates 11 of adjacent battery cell frames 1 can be communicated with each other. At the same time, the fire extinguishing groove 111 is an open structure at the upper part, so that the fire extinguishing member 3 can be directly installed in the fire extinguishing groove 111 from top to bottom, avoiding the situation that the fire extinguishing groove 111 is closed at the upper part, the fire extinguishing member 3 needs to be inserted into the fire extinguishing groove 111 along the length direction L of the battery module, which affects the installation efficiency and causes the fire extinguishing member 3 to be damaged or worn.

[0054] As shown, Figures 4 to 7 As an embodiment, the cover plate 11 is provided with a through hole 112 for the tab 21 of the battery cell 2 to pass through, and the tab 21 of the battery cell 2 extends out of the battery cell frame 1 through the through hole 112.

[0055] As shown, Figures 4 to 8 As an embodiment, the through hole 112 is a slot hole structure (i.e. the side wall of one side of the through hole 112 is an open structure), so as to facilitate the tab 21 of the battery cell 2 to pass through.

[0056] As shown, Figures 4 to 8 As an embodiment, the battery cell 2 is provided with two tabs 21, the two tabs 21 are arranged on the same side of the battery cell 2, and the two tabs 21 are arranged in a spaced manner; the cover plate 11 is arranged on the side of the battery cell 2 where the tabs 21 are located, the cover plate 11 is provided with two through holes 112, the two through holes 112 correspond to the two tabs 21 respectively, and the fire extinguishing groove 111 is arranged between the two through holes 112 (i.e. the fire extinguishing groove 111 is arranged at the middle position of the cover plate 11). Of course, in other embodiments, the fire extinguishing groove 111 can also be arranged at other positions simultaneously or individually, such as the outer side of the two through holes 112 (i.e. in the length direction of the cover plate 11, the fire extinguishing groove 111 is not arranged between the two through holes 112, in other words, in the length direction of the cover plate 11, the fire extinguishing groove 111 is arranged on one side or both sides of the two through holes 112, i.e. at both ends of the cover plate 11).

[0057] As shown, Figures 5 to 7 As an embodiment, the battery cell frame 1 further comprises a heat-conducting frame 12, which is located on one side of the cover plate 11 and connected with the cover plate 11 (the heat-conducting frame 12 is specifically located below the cover plate 11, and the top of the heat-conducting frame 12 is connected with the cover plate 11), and the heat-conducting frame 12 is provided with a battery cell mounting groove 123, and the battery cell 2 is arranged in the battery cell mounting groove 123.

[0058] Specifically, the heat-conducting frame 12 is made of a heat-conducting material (for example, a metal material), which can not only support and accommodate the battery cell 2 but also transfer heat, and can quickly conduct the heat generated by the battery cell 2 during normal operation; at the same time, the heat-conducting frame 12 can also block the flow of fire or high-temperature gas between adjacent heat-conducting frames 12 after the battery cell 2 experiences thermal runaway, reducing the impact of the battery cell 2 experiencing thermal runaway on other normal battery cells 2 in the heat-conducting frame 12.

[0059] As an embodiment, the cover plate 11 is made of a plastic material, and the heat-conducting frame 12 is connected to the cover plate 11 by a hot melt process.

[0060] As shown in Figure 5 and Figure 7 , as an embodiment, the heat-conducting frame 12 includes a main body portion 121, the top of the main body portion 121 is connected to the cover plate 11, and the edges of the other three sides of the main body portion 121 are provided with a folded edge 122, and a battery cell mounting groove 123 is formed by the main body portion 121 and the folded edge 122. The battery cells 2 in adjacent battery cell frames 1 are separated by the main body portion 121 of the heat-conducting frame 12, the folded edges 122 of adjacent battery cell frames 1 are lapped together, and the cover plates 11 of adjacent battery cell frames 1 are lapped together, thereby improving the support strength of the battery cell frame 1 and reducing the adverse effects caused by deformation of the battery cell frame 1 during stacking.

[0061] As shown in Figure 6 , Figure 7 ,

[0062] As shown in Figure 4 , Figure 6 , Figure 7 As an embodiment, the heat-conducting frame 12 is provided with a first step portion 124, the first step portion 124 is formed by the bottom wall of the heat-conducting frame 12 being recessed upward (the first step portion 124 is specifically provided on the folded edge 122 of the bottom of the heat-conducting frame 12), and the first step portion 124 can support the battery cell 2 upward. The first cable tie mounting groove 125 is provided on the bottom wall of the heat-conducting frame 12, and the position of the first cable tie mounting groove 125 corresponds to the position of the first step portion 124.

[0063] As shown in Figure 2 , Figure 4 , Figure 7 , Figure 8As shown, as an embodiment, the flow guide hole 1141 is arranged on the position corresponding to the fire extinguishing groove 111 on the battery cell frame 1, and the heat generated after the thermal runaway of the battery cell 2 can enter the fire extinguishing groove 111 from the battery cell frame 1 through the flow guide hole 1141, so that the fire extinguishing member 3 can be quickly heated to perform the fire extinguishing action, and the first fire extinguishing material released by the fire extinguishing member 3 after being broken by heating can enter the battery cell mounting groove 123 through the flow guide hole 1141.

[0064] As shown, Figure 8 As an embodiment, the flow guide hole 1141 is arranged on the bottom wall of the fire extinguishing groove 111.

[0065] As shown, Figure 2 , Figure 8 As an embodiment, the second cable tie mounting groove 113 for mounting the cable tie 6 is arranged on the bottom wall of the fire extinguishing groove 111, the second cable tie mounting groove 113 is formed by concave in the bottom wall of the fire extinguishing groove 111, the part of the bottom wall of the fire extinguishing groove 111 not concave forms a second step part 114, the flow guide hole 1141 is arranged on the second step part 114, the fire extinguishing member 3 is arranged corresponding to the second cable tie mounting groove 113, and the fire extinguishing member 3 is located above the second cable tie mounting groove 113, and the fire extinguishing member 3 does not cover the flow guide hole 1141 completely, so that the heat generated by the battery cell 2 can enter the fire extinguishing groove 111 through the uncovered part of the flow guide hole 1141 in time.

[0066] Specifically, by arranging the second cable tie mounting groove 113 in the fire extinguishing groove 111, it is beneficial to avoid that the second cable tie mounting groove 113 occupies the space of the cover plate 11 in the width direction of the battery module (i.e. the length direction of the cover plate 11) and limits the size of the battery module. At the same time, by arranging the flow guide hole 1141 on the second step part 114, it can avoid that the cable tie 6 or the fire extinguishing member 3 covers the flow guide hole 1141 and blocks the heat from entering the fire extinguishing groove 111, which is beneficial to discharge the heat from the flow guide hole 1141 to the fire extinguishing groove 111 as soon as possible in the initial stage of the thermal runaway, so as to delay the development of the thermal runaway.

[0067] As shown, Figure 8 As an embodiment, the second cable tie mounting groove 113 is arranged at the middle position of the bottom wall of the fire extinguishing groove 111. In the length direction of the cover plate 11, the second step part 114 is formed on the opposite sides of the second cable tie mounting groove 113, and the flow guide hole 1141 is arranged on the second step part 114 of the opposite sides.

[0068] As shown, Figure 2 and Figure 8 As an embodiment, the side wall 1142 of the second step part 114 near the second cable tie mounting groove 113 is arc-shaped or inclined, which is beneficial to the cable tie 6 sliding into the second cable tie mounting groove 113 during installation, and facilitates the installation of the cable tie 6.

[0069] As shown in Figure 4 and Figure 5 , as an embodiment, a plurality of battery cells 2 are arranged in the at least partial battery cell frame 1, and the plurality of battery cells 2 are arranged in sequence in the battery cell frame 1. A heat insulation pad 13 is arranged between the adjacent two battery cells 2 in the battery cell frame 1, and a tab edge isolation strip 14 is arranged on one side of the heat insulation pad 13. The tab edge isolation strip 14 is arranged at the edge position of the tab 21 of the battery cell 2.

[0070] Specifically, the heat insulation pad 13 is mainly used to block the heat transfer between the battery cells 2, delay the heat diffusion when the battery cell 2 is in thermal runaway, and buffer between the battery cells 2 to absorb a certain battery cell expansion and adjust the pressure in the module, thereby improving the service life of the battery cell 2. The heat insulation pad 13 can be made of a single material or a composite material according to requirements, such as a sandwich structure of mica plate + foamed foam or aerogel + mica plate.

[0071] The tab edge isolation strip 14 can separate the edge of the tabs 21 of the adjacent battery cells 2. As an embodiment, the tab edge isolation strip 14 is provided with a second fire extinguishing material. When the temperature of the tab edge isolation strip 14 reaches its melting point, the tab edge isolation strip 14 can break to release the second fire extinguishing material in the tab edge isolation strip 14.

[0072] Specifically, the tab edge isolation strip 14 includes a heat-fused shell and a second fire extinguishing material arranged in the shell. The shell can be made of a material with a melting point corresponding to the thermal runaway temperature. When the thermal runaway reaches the trigger temperature of the tab edge isolation strip 14, the tab edge isolation strip 14 breaks to release the second fire extinguishing material in the tab edge isolation strip 14, thereby cooling and extinguishing the battery cell 2 in thermal runaway in time. The second fire extinguishing material can be the same as the first fire extinguishing material.

[0073] As shown in Figure 1 , Figure 7 and Figure 8 , as an embodiment, the battery cell frame 1 is provided with a positioning pin 115 and a positioning hole 116 on opposite sides along the length direction L of the battery module. The positioning pin 115 on one of the adjacent two battery cell frames 1 can be inserted into the positioning hole 116 on the other battery cell frame 1 to realize the connection between the adjacent two battery cell frames 1.

[0074] As shown in Figure 7 and Figure 8As shown, as an embodiment, the positioning pin 115 and the positioning hole 116 are arranged on the cover plate 11, and the positioning pin 115 and the positioning hole 116 can be arranged at the middle position and / or the two end positions of the cover plate 11. Of course, in other embodiments, the positioning pin 115 and the positioning hole 116 can also be arranged at other positions on the battery cell frame 1, such as the heat-conducting frame 12.

[0075] As shown, Figure 1 and Figure 2 As shown, as an embodiment, the battery module further comprises a protective plate 4 arranged on the side of the battery cell assembly 100 corresponding to the position of the fire extinguishing device 3; the protective plate 4 is provided with an opening 41 at the position corresponding to the fire extinguishing device 3.

[0076] Specifically, the protective plate 4 can be a mica plate, which mainly plays a role of resisting flame impact and heat insulation. The protective plate 4 is provided with the opening 41, and the heat generated by the battery cell 2 can be discharged through the opening 41 in the initial stage of thermal runaway, so as to delay the spread of thermal runaway in the module and prevent explosion.

[0077] As shown, Figure 1 and Figure 2 As shown, as an embodiment, the battery module further comprises an end plate 5 and a cable tie 6, the end plate 5 is arranged at the opposite two ends of the battery cell assembly 100 along the length direction L of the battery module; the cable tie 6 is arranged around the battery cell assembly 100 and the end plate 5, and the cable tie 6 binds the battery cell assembly 100 and the end plate 5 together.

[0078] Specifically, Figure 2 , Figure 7 and Figure 8 As shown, the fire extinguishing groove 111 is arranged at the middle position of the cover plate 11, and the two ends of the cover plate 11 are further provided with third cable tie mounting grooves 117, and the bottom of the heat-conducting frame 12 is provided with three first cable tie mounting grooves 125, the first cable tie mounting groove 125 located at the middle of the heat-conducting frame 12 corresponds to the second cable tie mounting groove 113 at the middle of the cover plate 11, and the two first cable tie mounting grooves 125 located at the two ends of the heat-conducting frame 12 correspond to the two third cable tie mounting grooves 117 at the two ends of the cover plate 11. The number of the cable tie 6 is three, one of which is installed in the second cable tie mounting groove 113 of the cover plate 11 and the first cable tie mounting groove 125 at the middle of the heat-conducting frame 12, and the fire extinguishing device 3 is arranged on the cable tie 6; the other two cable ties 6 are installed in the two third cable tie mounting grooves 117 at the two ends of the cover plate 11 and the two first cable tie mounting grooves 125 at the two ends of the heat-conducting frame 12, so as to firmly fix the battery cell assembly 100 and the end plate 5 together.

[0079] As an embodiment, the fire-extinguishing groove 111 can also be arranged outside the two through holes 112, i.e. at the two ends of the cover plate 11 in the length direction of the cover plate 11. In the length direction of the cover plate 11, the third cable tie mounting groove 117 can not be arranged between the two through holes 112 or outside the two through holes 112.

[0080] As another embodiment, the battery cell 2 is provided with two opposite tabs 21 (i.e. the two tabs 21 on the battery cell 2 are arranged at opposite ends of the battery cell 2, not shown in the figure), and the battery cell frame 1 comprises two cover plates 11 arranged at opposite sides of the battery cell 2, respectively, and the two cover plates 11 correspond to the two tabs 21 of the battery cell 2, respectively. At this time, the two cover plates 11 are arranged at opposite sides of the main body part 121 of the heat-conducting frame 12, and the edge positions of the other two sides of the main body part 121 are provided with the folded edges 122 (not shown in the figure). Further, each cover plate 11 is provided with one through hole 112, and at this time, the through hole 112 is arranged at the middle position of the cover plate 11, and the fire-extinguishing groove 111 is arranged at one side or opposite sides of the through hole 112 in the length direction of the cover plate 11. At the same time, if one side of the two sides of the through hole 112 in the length direction of the cover plate 11 is not provided with the fire-extinguishing groove 111, the third cable tie mounting groove 117 (not shown in the figure) is arranged at the side.

[0081] As an embodiment, the battery module further comprises an insulating guard plate (not shown in the figure) arranged between the battery cell assembly 100 and the protective plate 4, and a signal acquisition plate (not shown in the figure) arranged between the insulating guard plate and the protective plate 4, the signal acquisition plate extends along the length direction L of the battery module, and the extension part of the signal acquisition plate is provided with a notch (not shown in the figure). The end plate 5 is provided with the insulating seat 7, and the insulating seat 7 is provided with the protrusion 71 (the notch on the signal acquisition plate is clamped on the protrusion 71) for cooperating with the notch on the signal acquisition plate, so as to fix the extension end of the signal acquisition plate on the insulating seat 7.

[0082] As shown in Figure 3 , Figure 6 , Figure 9 and Figure 10 , as an embodiment, the battery module further comprises a busbar 8, the busbar 8 is arranged at the side of the cover plate 11 away from the battery cell 2, and the busbar 8 is arranged between the battery cell assembly 100 and the insulating guard plate; the busbar 8 is provided with a tab slot 81 for the tab 21 of the battery cell 2 to pass through, and the tab 21 of the battery cell 2 is sequentially arranged through the through hole 112 and the tab slot 81 and electrically connected with the busbar 8.

[0083] As shown in Figure 9 and Figure 10As shown, as an embodiment, the tab 21 of the battery cell 2 is bent to make the tab 21 adhere to the surface of the busbar 8 away from the battery cell 2 after the tab 21 passes through the tab slot 81 on the busbar 8, and then the tab 21 and the busbar 8 are welded and fixed.

[0084] As shown in Figure 10 , as an embodiment, the busbar 8 includes a first connecting portion 82, a second connecting portion 84, and a grid portion 83 between the first connecting portion 82 and the second connecting portion 84, the grid portion 83 includes a plurality of flow guide strips 831, the plurality of flow guide strips 831 are arranged at intervals along the length direction L of the battery module, and the opposite ends of each flow guide strip 831 are connected to the first connecting portion 82 and the second connecting portion 84, respectively. The tab slot 81 is formed between two adjacent flow guide strips 831.

[0085] As shown in Figure 9 and Figure 10 , as an embodiment, the thickness of the grid portion 83 is less than the thickness of the first connecting portion 82, and a step is formed at the joint of the grid portion 83 and the first connecting portion 82, so that the surface of the tab 21 after bending can be substantially flush with the surface of the first connecting portion 82, without protruding from the surface of the busbar 8. At the same time, the thickness of the second connecting portion 84 is the same as the thickness of the grid portion 83; of course, in other embodiments, the thickness of the second connecting portion 84 can also be the same as the thickness of the first connecting portion 82.

[0086] As shown in Figure 3 , Figure 9 and Figure 10 , as an embodiment, the busbar 8 is provided with a plurality of tab slots 81, and the plurality of tab slots 81 are arranged in sequence along the length direction L of the battery module; each busbar 8 corresponds to one battery cell frame 1, and the plurality of tab slots 81 on each busbar 8 are used for the tabs 21 of the plurality of battery cells 2 in one battery cell frame 1 to pass out.

[0087] As shown in Figure 11 and in conjunction with Figure 3 , as another embodiment, the busbar 8 is provided with a plurality of tab slots 81, and the plurality of tab slots 81 are arranged in sequence along the length direction L of the battery module; each busbar 8 corresponds to a plurality of battery cell frames 1, and the plurality of tab slots 81 on each busbar 8 are used for the tabs 21 of the battery cells 2 in the plurality of battery cell frames 1 to pass out at the same time.

[0088] As shown in Figure 12 and in conjunction with Figure 3As another embodiment, the busbar 8 includes a first connecting portion 82 and a grid portion 83 located on one side of the first connecting portion 82 (i.e. without the second connecting portion 84), and the grid portion 83 includes a plurality of flow guide strips 831 arranged at intervals along the length direction L of the battery module, one end of each flow guide strip 831 being connected to the first connecting portion 82, and the tab slot 81 being formed between two adjacent flow guide strips 831, and each flow guide strip 831 being provided with a chamfer at the other end away from the first connecting portion 82.

[0089] As shown in FIG. 1, as an embodiment, the busbar 8 is provided with a positioning slot 85 for positioning, and the positioning slot 85 is arranged on the first connecting portion 82. The positioning slot 85 is used for positioning the tab bending equipment to align the tab 21 for bending. Figure 10

[0090] As an embodiment, the inner wall of the tab slot 81 on the side close to the cover plate 11 is an outwardly expanding inclined surface structure (i.e. the tab slot 81 on the side close to the cover plate 11 is a trapezoidal structure), so as to facilitate the insertion of the tab 21 into the tab slot 81.

[0091] The battery module provided by the embodiment of the present application reduces the influence of the arrangement of the fire extinguishing member 3 on the outer size of the battery module, improves the compactness of the structure of the battery module, and protects the fire extinguishing member 3 from being damaged by pressure. At the same time, since the fire extinguishing channel 110 is composed of the fire extinguishing slots 111 on the plurality of cell frames 1, when a cell 2 at a position in the cell assembly 100 catches fire, the fire extinguishing member 3 can respond in time to extinguish the fire, i.e. the fire extinguishing range of the fire extinguishing member 3 covers the entire cell assembly 100, so the utilization rate of the fire extinguishing member 3 is high, and the fire extinguishing efficiency is high. Moreover, during assembly, the fire extinguishing member 3 only needs to be arranged in the fire extinguishing channel 110 once, and it is not necessary to arrange the fire extinguishing member 3 for each cell frame 1 separately, thereby facilitating the assembly efficiency of the battery module. The battery module is not only compact and easy to assemble, but also has high fire extinguishing efficiency.

[0092] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which shall be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.​

Claims

1. A battery module, characterized by, The battery module comprises an electric cell assembly (100) and a fire extinguishing device (3), the electric cell assembly (100) comprises a plurality of electric cell frames (1) and a plurality of electric cells (2), the plurality of electric cell frames (1) are arranged in sequence along the length direction (L) of the battery module, and at least part of the electric cell frames (1) are provided with at least one electric cell (2); each electric cell frame (1) is provided with a fire extinguishing groove (111), the fire extinguishing grooves (111) on the plurality of electric cell frames (1) are communicated with each other to form a fire extinguishing channel (110), and the fire extinguishing device (3) is arranged in the fire extinguishing channel (110); the fire extinguishing groove (111) extends along the length direction (L) of the battery module and penetrates the electric cell frame (1), the fire extinguishing channel (110) extends along the length direction (L) of the battery module, and the fire extinguishing device (3) extends along the length direction (L) of the battery module in the fire extinguishing channel (110). A second cable tie mounting groove (113) for mounting a cable tie (6) is arranged on the bottom wall of the fire extinguishing groove (111), a flow guide hole (1141) is arranged on the electric cell frame (1) at a position corresponding to the fire extinguishing groove (111), and heat generated after thermal runaway of the electric cell (2) can enter the fire extinguishing groove (111) through the flow guide hole (1141); the second cable tie mounting groove (113) is formed by concave part of the bottom wall of the fire extinguishing groove (111), a second step part (114) is formed on the bottom wall of the fire extinguishing groove (111) which is not concave, and the flow guide hole (1141) is arranged on the second step part (114).

2. The battery module of claim 1, wherein, The fire extinguishing device (3) is provided with a first fire extinguishing material, and when the temperature of the fire extinguishing device (3) reaches the melting point, the fire extinguishing device (3) can be broken to release the first fire extinguishing material in the fire extinguishing device (3).

3. The battery module of claim 1, wherein, The electric cell (2) is provided with a tab (21), and the fire extinguishing groove (111) is arranged on the electric cell frame (1) at a side corresponding to the tab (21) of the electric cell (2).

4. The battery module of claim 3, wherein, The electric cell frame (1) comprises a cover plate (11), the cover plate (11) is arranged at a side corresponding to the tab (21) of the electric cell (2), and the fire extinguishing groove (111) is arranged on the cover plate (11).

5. The battery module of claim 4, wherein, The cover plate (11) is provided with a through hole (112) for the tab (21) of the electric cell (2) to pass through.

6. The battery module of claim 5, wherein, The electric cell (2) is provided with two tabs (21) on the same side, and the two tabs (21) are arranged at intervals; the cover plate (11) is arranged on the side where the tabs (21) of the electric cell (2) are located, the cover plate (11) is provided with two through holes (112), the two through holes (112) correspond to the two tabs (21) respectively, the fire extinguishing groove (111) is arranged between the two through holes (112); and / or the fire extinguishing groove (111) is arranged outside the two through holes (112).

7. The battery module of claim 6, wherein, The electric cell frame (1) further comprises a heat-conducting frame (12) connected to the cover plate (11), wherein the heat-conducting frame (12) is provided with an electric cell mounting groove (123), and the electric cell (2) is arranged in the electric cell mounting groove (123).

8. The battery module of claim 7, wherein, The heat-conducting frame (12) is provided with a first cable tie mounting groove (125) for mounting a cable tie (6).

9. The battery module of claim 5, wherein, The electric cell (2) is provided with two tab ears (21) located on opposite sides, the electric cell frame (1) comprises two cover plates (11), the two cover plates (11) are arranged on opposite sides of the electric cell (2) respectively, and the two cover plates (11) correspond to the two tab ears (21) of the electric cell (2) respectively, each cover plate (11) is provided with a through hole (112), and the fire extinguishing groove (111) is arranged on one side or opposite sides of the through hole (112).

10. The battery module of claim 5, wherein, The battery module further comprises a bus bar (8), the bus bar (8) is arranged on the side of the cover plate (11) away from the electric cell (2), the bus bar (8) is provided with a tab ear groove (81) for the tab ear (21) of the electric cell (2) to pass through, and the tab ear (21) of the electric cell (2) is sequentially arranged through the through hole (112) and the tab ear groove (81) and electrically connected with the bus bar (8).

11. The battery module of claim 1, wherein, The fire extinguishing member (3) is arranged corresponding to the second cable tie mounting groove (113), and the fire extinguishing member (3) does not cover the flow guide hole (1141) completely.

12. The battery module of claim 1, wherein, The battery module further comprises a protection plate (4), the protection plate (4) is arranged on the side of the electric cell assembly (100) corresponding to the fire extinguishing member (3), and the protection plate (4) is provided with an opening (41) at a position corresponding to the fire extinguishing member (3).

13. The battery module of any one of claims 1-12, wherein, The fire extinguishing member (3) is in a long strip structure, and the fire extinguishing member (3) extends from one end of the fire extinguishing channel (110) to the opposite end of the fire extinguishing channel (110).

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