Battery module and battery pack

Abstract

The utility model provides a battery module and a battery pack. The battery module comprises a plurality of single batteries, an integrated busbar and a fireproof belt, a pressure release valve is arranged at the top of each single battery, the integrated busbar is arranged on one side of the top of each single battery, the fireproof belt is arranged on one side, away from the single batteries, of the integrated busbar, and through holes in one-to-one correspondence with the pressure release valves are formed in the fireproof belt. According to the embodiment of the invention, the fireproof belt is arranged on one side, far away from the battery monomers, of the integrated busbar, the fireproof belt is provided with a plurality of through holes, and the through holes are exposed out of the pressure release valves at the tops of the battery monomers, so that when the battery monomers are subjected to thermal runaway, the pressure release valves are opened, and conductor substances sprayed out along with gas can be separated by the fireproof belt; and the technical problem of continuous heat diffusion caused by short circuit of other battery monomers in the battery module due to contact between the conductor substance and the battery monomers and / or the integrated busbar is avoided.

Description

TECHNICAL FIELD

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

[0002] The battery module includes a plurality of battery cells. In the related art, after thermal runaway of a battery cell, a pressure relief valve of the battery cell is opened to release the pressure inside the battery cell. The conductive substances inside the battery cell, such as pole pieces, graphite, and metal particles, will be ejected upwards along with the airflow inside the battery cell. The conductive substances can easily cause short circuits of other battery cells in the battery module, thereby triggering continuous thermal diffusion.

[0003] Therefore, it is urgent to solve the above technical problems. UTILITY MODEL CONTENT

[0004] Embodiments of the present application provide a battery module and a battery pack, which can improve the technical problem that the conductive substances ejected after thermal runaway of a battery cell cause short circuits of other battery cells in the battery module, thereby triggering continuous thermal diffusion.

[0005] In a first aspect, embodiments of the present application provide a battery module, which includes:

[0006] a plurality of battery cells, a top portion of each battery cell being provided with a pressure relief valve;

[0007] an integrated busbar provided on one side of the top portion of each battery cell;

[0008] a fireproof belt provided on a side of the integrated busbar away from the battery cells, the fireproof belt being provided with a through hole corresponding to each pressure relief valve.

[0009] In an embodiment, an insulating portion is arranged in the through hole, and the insulating portion is connected to the side wall of the through hole through a weak structure.

[0010] In an embodiment, the weak structure includes a plurality of connecting ribs, and the connecting ribs are arranged along the edge of the insulating portion.

[0011] In an embodiment, one side surface of the fireproof belt is provided with an insulating film, the insulating film covers each through hole, and the thickness of the insulating film is less than the thickness of the fireproof belt.

[0012] In an embodiment, each battery cell includes a first electrode and a second electrode arranged on the same end surface of the battery cell as the pressure relief valve, the first electrode is arranged around the pressure relief valve, and the pressure relief valve is arranged around the second electrode.

[0013] In an embodiment, the integrated busbar includes a busbar, the busbar includes a plurality of busbars arranged in a first direction, the busbars are connected in series to a plurality of the battery cells, the busbar includes a first sub-portion connected to the first electrode, a second sub-portion connected to the second electrode, and a first weak portion connecting the first sub-portion and the second sub-portion, the through hole exposes the second sub-portion and at least part of the first weak portion, the cross-sectional area of the first sub-portion and the second sub-portion is greater than the cross-sectional area of the first weak portion, and the second sub-portion is connected to the second electrode.

[0014] In an embodiment, the busbar includes a second weak portion, the second weak portion connects two adjacent second sub-portions, the through hole exposes the second weak portion, and the cross-sectional area of the second sub-portion is greater than the cross-sectional area of the second weak portion.

[0015] In an embodiment, the integrated busbar includes a bracket, the bracket is arranged between the busbar and the battery cell, the bracket is used to support the busbar, the busbar includes a connecting arm, two ends of the connecting arm are respectively connected to a second weak portion, and the bracket is provided with a groove, and a connecting arm is arranged in the groove.

[0016] In an embodiment, the pressure relief valve is in a circular ring shape, the through hole is a circular hole, the diameter of the through hole is greater than the outer diameter of the pressure relief valve and less than the outer diameter of the cylindrical battery cell.

[0017] In a second aspect, embodiments of the present application provide a battery pack, the battery pack including the battery module described above.

[0018] The beneficial effects of embodiments of the present application are as follows:

[0019] In embodiments of the present application, by arranging a fireproof belt on the side of the integrated busbar away from the battery cell, the fireproof belt is provided with a plurality of through holes, the through holes expose the pressure relief valve at the top of the battery cell, when the battery cell is in thermal runaway, the pressure relief valve is opened, and the conductor material sprayed with gas can be separated by the fireproof belt, avoiding the conductor material from contacting the battery cell and / or the integrated busbar to cause short circuit of other battery cells in the battery module and trigger the technical problem of continuous thermal diffusion. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0021] Figure 1is a perspective view of a battery module provided by an embodiment of the present application;

[0022] Figure 2 is Figure 1 is an exploded view of the battery module in

[0023] Figure 3 is Figure 1 is an enlarged structural view of the battery cell in

[0024] Figure 4A is Figure 2 is a top view of the fireproof belt in

[0025] Figure 4B is Figure 2 is another top view of the fireproof belt in

[0026] Figure 5A is Figure 2 is an exploded view of the integrated busbar in

[0027] Figure 5B is Figure 1 is a top view of a partial structure of the battery module in

[0028] Figure 6 is Figure 5A is an enlarged structural view of the flow guide in

[0029] Figure 7 is Figure 5A is an enlarged structural view of A in

[0030] Figure 8 is a structural view of a battery pack provided by an embodiment of the present application.

[0031] Legend:

[0032] battery module 1;

[0033] battery cell 10, shell 12, cover plate assembly 11, pressure relief valve 111, pole 112, first electrode 113, second electrode 114;

[0034] integrated busbar 20, busbar 21, flow guide 211, first sub-portion 2111, second sub-portion 2112, first weak portion 2113, second weak portion 2114, connecting arm 2115, first busbar end 212, second busbar end 213, bracket 22, recess 221, flexible circuit board 23, connecting tab 231;

[0035] fireproof belt 30, through hole 31, insulating portion 32, weak structure 34, insulating film 33;

[0036] first direction D1, second direction D2;

[0037] Battery pack 2. Detailed Implementation

[0038] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. In addition, it should be understood that the specific embodiments described herein are only for illustration and explanation of this application and are not intended to limit this application. In this application, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in actual use or operation, specifically the drawing directions in the accompanying drawings; while "inner" and "outer" refer to the outline of the device.

[0039] In a first aspect, embodiments of this application provide a battery module 1, such as... Figures 1 to 3 As shown, the battery module 1 includes multiple battery cells 10, an integrated busbar 20, and a fireproof strip 30. A pressure relief valve 111 is provided on the top of the battery cell 10. The integrated busbar 20 is located on one side of the top of the multiple battery cells 10. The fireproof strip 30 is located on the side of the integrated busbar 20 away from the battery cells 10. The fireproof strip 30 is provided with through holes 31 that correspond one-to-one with the pressure relief valve 111.

[0040] In this embodiment, the battery cell 10 can be a cylindrical battery, a prismatic battery, etc. The accompanying drawings of this application use a cylindrical battery as an example for illustration and should not be construed as limiting the scope of this application.

[0041] like Figure 3 As shown, the top of the battery cell 10 refers to the end of the battery cell 10 where the cover assembly 11 is provided. The battery cell 10 typically includes a housing 12 with an opening. The cover assembly 11 is provided corresponding to the opening of the housing 12, and the cover assembly 11 and the housing 12 form a sealed receiving space to accommodate electrode sheets (not shown in the figure) and other materials disposed inside the housing 12.

[0042] The top of the battery cell 10 is provided with a pressure relief valve 111. The battery cell 10 includes oppositely arranged top and bottom surfaces, and the surface connecting the top and bottom surfaces is a side surface. The cover plate assembly 11 is arranged corresponding to the top surface of the battery cell 10, and the shell 12 is arranged corresponding to the bottom and side surfaces of the battery cell 10. The pressure relief valve 111 can be arranged on the cover plate assembly 11. When the battery cell 10 experiences thermal runaway, the air pressure inside the shell 12 increases, the pressure relief valve 111 opens, and an outlet for gas flow is formed. The conductor substances in the battery cell 10, such as the pole piece, graphite, and metal particles, are ejected from the outlet along with the gas. After the valve is opened, the gas in the battery cell 10 can be normally discharged, avoiding explosion of the battery cell 10 due to high internal pressure.

[0043] The integrated busbar 20 refers to a CCS (Cells Contact System) assembly. As shown in Figure 2 , the integrated busbar 20 is arranged on one side of the top of the battery cell 10. The integrated busbar 20 is mainly used to realize series and parallel connection of a plurality of battery cells 10 to output current. The integrated busbar 20 can also be used to collect voltage data of the battery cell, monitor the temperature of the battery cell, and provide an equalization channel to ensure safe and stable operation of the battery module 1.

[0044] As shown in Figure 1 and Figure 2 , the fireproof belt 30 is arranged on the side of the integrated busbar 20 away from the battery cell 10. The fireproof belt 30 is provided with a plurality of through holes 31, one through hole 31 corresponding to one pressure relief valve 111 of the battery cell 10, and the through hole 31 is used to expose the pressure relief valve 111. When the pressure relief valve 111 is opened, the ejected gas can be ejected from the through hole 31. By arranging the through hole 31 on the fireproof belt 30, the flow of the opened valve can be avoided to be blocked by the arranged fireproof belt 30.

[0045] The outer shape of the fireproof belt 30 does not exceed the outer shape of the integrated busbar 20, so as to avoid increasing the outer dimension of the battery module 1 due to the arrangement of the fireproof belt 30. A plurality of positioning holes can be arranged on the fireproof belt 30, and a plurality of positioning columns can be arranged on the integrated busbar 20, so as to realize positioning and assembly of the fireproof belt 30 and the integrated busbar 20.

[0046] The fireproof belt 30 can be made of fireproof and insulating material. The fireproof belt 30 can separate the conductor substances ejected along with the flow of the opened valve, and prevent the conductor substances from contacting the integrated busbar 20 and / or the battery cell 10 to cause short circuit of the adjacent battery cell 10. After the adjacent battery cell 10 is short-circuited, continuous thermal runaway will be caused, leading to failure of the battery module 1.

[0047] The material of the fireproof belt 30 can be made of fireproof, high-temperature resistant and insulating material. In this way, not only can the contact between the conductor material and the integrated busbar 20 and / or the battery monomer 10 be prevented, which can cause short circuit of the adjacent battery monomers 10, but also the heat diffusion and heat spread after the valve of the battery monomer 10 is opened can be effectively inhibited.

[0048] In some embodiments, the fireproof belt 30 can be composed of a single layer or multiple layers of material. For example, the fireproof belt 30 can include a double-sided adhesive tape, a fiberglass cloth and a ceramic silicone rubber layer. The double-sided adhesive tape is used to bond with the integrated busbar 20 to fix the fireproof belt 30. The fireproof belt 30 can also be made of other fireproof and insulating materials, and the material of the fireproof belt 30 is not limited in the present application.

[0049] In some embodiments, the fireproof belt 30 can be made of a phase change material. At high temperature, the surface layer of the phase change material can quickly obtain high strength, and at the same time, a large number of micropores can be generated in the material, and the thermal conductivity coefficient can be sharply reduced to achieve good heat insulation effect.

[0050] When the pressure in the battery monomer 10 is large, the pressure relief valve 111 can be separated from the shell 12 and fall off. The position where the pressure relief valve 111 falls off is random. When the fallen pressure relief valve 111 is connected with the integrated busbar 20 and / or the adjacent battery monomer 10, it can cause short circuit between the battery monomer 10 and / or the integrated busbar 20 in the adjacent two through holes 31, and can cause continuous heat diffusion phenomenon.

[0051] In view of this, as shown in FIG. 3, in some embodiments, an insulating part 32 is arranged in the through hole 31 of the fireproof belt 30, so that the insulating material in the through hole 31 can separate the pressure relief valve 111, and prevent the fallen pressure relief valve 111 from causing short circuit between the battery monomer 10 and / or the integrated busbar 20 in the adjacent two through holes 31. Figure 4A In some embodiments, as shown in FIG. 3, the insulating part 32 is connected with the fireproof belt 30 through a weak structure 34. The insulating part 32 in the through hole 31 can be made of the same material as the fireproof belt 30. Through the above arrangement, the insulating part 32 and the fireproof belt 30 can be integrally formed, and the manufacturing process of the insulating part 32 can be simplified.

[0052] Figure 4A The mechanical strength of the weak structure 34 is less than that of the fireproof belt 30 and the insulating part 32. When the pressure relief valve 111 is opened, the airflow of the opened valve can cause the weak structure 34 to break, so that the insulating part 32 is separated from the fireproof belt 30.

[0053] Optionally, as shown in FIG. 3, the insulating part 32 can be arranged in the through hole 31 of the fireproof belt 30. The insulating part 32 can be made of a material with high thermal conductivity, such as aluminum foil, so that the heat generated by the battery monomer 10 can be quickly conducted away, and the temperature rise of the battery monomer 10 can be effectively inhibited.

[0054] Optionally, as shown in FIG. 3, the insulating part 32 can be arranged in the through hole 31 of the fireproof belt 30. The insulating part 32 can be made of a material with high thermal conductivity, such as aluminum foil, so that the heat generated by the battery monomer 10 can be quickly conducted away, and the temperature rise of the battery monomer 10 can be effectively inhibited. Figure 4A ​As shown, the weak structure 34 can be a connecting rib, and there can be multiple connecting ribs. The multiple connecting ribs are distributed circumferentially along the through hole 31, connecting the edge of the insulating part 32 to the side wall of the through hole 31. It should be noted that the number and size of the connecting ribs can be set as needed, as long as it is ensured that the connecting ribs can be broken by the airflow when the valve is opened.

[0055] In some embodiments, the weak structure 34 can be a notch, and the insulating part 32 and the fireproof strip 30 are connected by multiple notches. The material at the notch is thinner and can be broken by the airflow when the valve is opened. The shape of the notch can be set as needed so that when the notch breaks, the insulating part 32 separates from the fireproof strip 30.

[0056] Because the connection between the insulation part 32 and the fireproof strip 30 is weak, when the pressure relief valve 111 is opened, the impact force of the airflow can break the weak structure 34, thereby preventing the insulation part 32 from obstructing the airflow. The fallen pressure relief valve 111 can be separated by the insulation part 32, thereby preventing the fallen pressure relief valve 111 from causing a short circuit between the battery cells 10 and / or the integrated busbar 20 in the two adjacent through holes 31.

[0057] In one embodiment, such as Figure 4B As shown, an insulating film 33 is provided on one side surface of the fireproof strip 30, covering each through hole 31. The thickness of the insulating film 33 is less than the thickness of the fireproof strip 30. The insulating film 33 can be bonded to the fireproof strip 30. The material of the insulating film 33 can be the same as or different from the material of the fireproof strip 30. The insulating film 33 can be a fireproof, high-temperature resistant, and insulating material, thereby achieving an insulating effect on the one hand, and isolating the airflow from the valve opening from other non-thermal runaway battery cells 10 on the other hand, preventing other non-thermal runaway battery cells 10 from failing due to the high-temperature airflow.

[0058] The thickness of the insulating film 33 is less than the thickness of the fireproof strip 30. The thickness of the insulating film 33 can be set as needed, as long as it can be broken by the airflow when the valve is opened.

[0059] When the pressure relief valve 111 is opened, the impact force of the airflow can break through the insulating membrane 33, thereby preventing the insulating membrane 33 from obstructing the airflow. The fallen pressure relief valve 111 can be separated by the insulating membrane 33, thereby preventing the fallen pressure relief valve 111 from causing a short circuit between the battery cells 10 and / or the integrated busbar 20 in the two adjacent through holes 31.

[0060] In some embodiments, the insulating film 33 can be a single sheet of film. When the insulating film 33 is a single sheet of film, the processing technology of the insulating film 33 is relatively simple.

[0061] In some embodiments, the insulating film 33 may also include a plurality of independent insulator portions, with one insulator portion corresponding to a through hole 31.

[0062] In an embodiment, as shown in FIG. 1, the battery cell 10 includes a housing 12 and a cover plate assembly 11, the cover plate assembly 11 forms a sealed structure with the housing 12, the cover plate assembly 11 includes a pole 112 and a pressure relief valve 111, the cover plate assembly 11 is provided with a notch to form the pressure relief valve 111, and the notch is arranged around the pole 112. Figure 3

[0063] In the embodiment, the housing 12 can be a metal material, such as aluminum, copper, etc. The notch can be in the form of a groove, a cutout, etc. Since the thickness at the notch is smaller than the thickness at other positions, when the pressure inside the battery cell 10 reaches the valve opening threshold, the notch breaks to facilitate pressure relief. The notch is a closed figure around the pole 112, so that when the valve is opened, the pressure relief valve 111 can be detached together with the pole 112.

[0064] The pressure relief valve 111 is insulated and connected with the pole 112, for example, a sealing ring is arranged between the pressure relief valve 111 and the pole 112, which can realize the connection and sealing between the pressure relief valve 111 and the pole 112. When the pressure relief valve 111 is detached, the pole 112 is detached together with the pressure relief valve 111. Thus, the current loop of the battery cell 10 can be broken, avoiding the influence of the thermal runaway battery cell 10 on other battery cells 10.

[0065] For example, as shown in FIG. 1, the pressure relief valve 111 is coaxially arranged with the pole 112, the pressure relief valve 111 is in the form of a circular ring, and the pole 112 is arranged at the center region of the circular ring of the pressure relief valve 111. Figure 3

[0066] In an embodiment, as shown in FIG. 2, the cover plate assembly 11 includes a first electrode 113 and a second electrode 114, the first electrode 113 is arranged around the pressure relief valve 111, the outer edge of the first electrode 113 is connected with the housing 12, the inner edge of the first electrode 113 is connected with the pressure relief valve 111, and the second electrode 114 is connected with the pole 112. Figure 3 One of the first electrode 113 and the second electrode 114 can be a positive electrode, and the other can be a negative electrode. For example, the first electrode 113 can be a negative electrode, and the second electrode 114 can be a positive electrode. The first electrode 113 is arranged around the pressure relief valve 111, and the first electrode 113 can also be in the form of a circular ring. The first electrode 113 is coaxially arranged with the pole 112.

[0067]

[0068] ​​​The inner edge of the first electrode 113 is arranged in connection with the pressure relief valve 111, and the outer edge of the first electrode 113 is arranged in connection with the shell 12. The inner edge of the first electrode 113 corresponds to the inner edge of the annular ring of the first electrode 113, and the outer edge of the first electrode 113 corresponds to the outer edge of the annular ring of the second electrode 114. The second electrode 114 is arranged in connection with the pole column 112, for example, the second electrode 114 can be arranged in welding connection with the pole column 112. Through the above arrangement, the first electrode 113, the second electrode 114, and the pressure relief valve 111 can be arranged at one end of the shell 12, thereby simplifying the structure of the battery monomer 10 and reducing the process difficulty.

[0069] In an embodiment, as shown in Figure 5A , Figure 5B and Figure 6 , the integrated busbar 20 includes a busbar 21, the busbar 21 includes a plurality of flow guides 211 arranged in a first direction, the flow guides 211 are connected in series to a plurality of battery monomers 10, the flow guides 211 include a first sub-portion 2111 connected with the first electrode 113, a second sub-portion 2112 connected with the second electrode 114, and a first weak portion 2113 connecting the first sub-portion 2111 and the second sub-portion 2112, and the through hole 31 exposes the second sub-portion 2112 and at least part of the first weak portion 2113.

[0070] As shown in Figure 5A and Figure 5B , the integrated busbar 20 includes a busbar 21, the busbar 21 is used to realize the series-parallel connection of a plurality of battery monomers 10 to output current. Specifically, the busbar 21 includes a second busbar end 213, a plurality of flow guides 211, and a first busbar end 212 arranged in a first direction D1 in sequence. When the first electrode 113 is a negative electrode and the second electrode 114 is a positive electrode, the second busbar end 213 can be used to output a positive voltage, and the first busbar end 212 can be used to output a negative voltage. The busbar 21 is used to connect two adjacent battery monomers 10 in series in the first direction D1 and connect two adjacent battery monomers 10 in parallel in the second direction D2. The first direction D1 is the length direction of the busbar 21, and the second direction D2 is the width direction of the busbar 21.

[0071] As shown in Figure 5B and Figure 6 , each flow guide 211 includes a plurality of first sub-portions 2111 and a plurality of second sub-portions 2112, the first sub-portions 2111 are connected with the first electrodes 113, and the second sub-portions 2112 are connected with the second electrodes 114. The first electrode 113 and the second electrode 114 can not be in the same horizontal plane. For example, the plane where the second electrode 114 is located can be higher than the plane where the first electrode 113 is located, thereby avoiding short circuit of the busbar 21 when connecting the first electrode 113 and the second electrode 114.

[0072] The first weak portion 2113 is arranged between the first sub portion 2111 and the second sub portion 2112, and has a cross-sectional area smaller than that of the first sub portion 2111 and smaller than that of the second sub portion 2112. The cross-sectional area is perpendicular to the direction of the current in the bus bar 211.

[0073] The material of the bus bar 21 can be metal such as aluminum or copper. When the battery cell 10 is in thermal runaway, the current in the first weak portion 2113 corresponding to the battery cell 10 increases, causing the first weak portion 2113 to melt. The first weak portion 2113 functions as a fuse, and is used to disconnect the battery cell 10 in thermal runaway from the series circuit, thereby avoiding the influence of the battery cell 10 in thermal runaway on other battery cells 10.

[0074] In an embodiment, the bus bar 211 includes a second weak portion 2114, which connects two adjacent second sub portions 2112. The through hole 31 exposes the second weak portion 2114.

[0075] The bus bar 211 includes a plurality of second weak portions 2114, each of which connects two adjacent battery cells 10 in the second direction D2. At least two second weak portions 2114 are arranged between the two adjacent battery cells 10, and each of the two second weak portions 2114 is used to disconnect one of the battery cells 10. The second weak portion 2114 also functions as a fuse, and has a similar principle of action as the first weak portion 2113. The difference is that when the battery cell 10 is in thermal runaway, the first weak portion 2113 melts, and at this time the second weak portion 2114 does not melt. When a short circuit occurs in the integrated bus bar 20, the second weak portion 2114 melts. This means that although the first weak portion 2113 can melt in time when the battery cell 10 is in thermal runaway, the battery cell 10 in thermal runaway cannot be disconnected from the parallel-connected plurality of battery cells 10, which can easily cause continuous thermal runaway.

[0076] To this end, the second weak portion 2114 is arranged on the bus bar 211, and the first weak portion 2113 and the second weak portion 2114 are exposed to the through hole 31. When the pressure relief valve 111 is opened, the second weak portion 2114 can be disconnected under the impact force of the gas jet, thereby disconnecting the battery cell 10 in thermal runaway from the parallel-connected plurality of battery cells 10, and further reducing the influence of the battery cell 10 in thermal runaway on other battery cells 10. In this way, even if a short circuit does not occur in the integrated bus bar 20, the battery cell 10 in thermal runaway can be disconnected from the parallel circuit in time.

[0077] The second sub-portion 2112 and at least part of the first weak portion 2113 are exposed to the through hole 31, so when the battery monomer 10 is in thermal runaway, the pole 112, the second sub-portion 2112, and the pressure relief valve 111 fall off together, and then fly out of the through hole 31 along with the valve opening gas flow, so that the pressure relief valve 111 of the battery monomer 10 can normally open, and the gas in the battery monomer 10 can be normally discharged, avoiding explosion and deflagration of the battery monomer 10.

[0078] In an embodiment, as shown in Figure 2 、 Figure 5A 、 Figure 5B and Figure 7 , the integrated busbar 20 includes a bracket 22, which is arranged between the busbar 21 and the battery monomer 10, and is used to carry the busbar 21. The flow guide 211 includes a connecting arm 2115, both ends of which are connected to a second weak portion 2114. The bracket 22 is provided with a groove 221, and a connecting arm 2115 is arranged in a groove 221.

[0079] As shown in Figure 5A and Figure 5B , the bracket 22 is provided with a carrying groove on one side surface close to the busbar 21, which is used to accommodate the busbar 21. The bracket 22 is also provided with a plurality of openings, which expose the top of each battery monomer 10. The busbar 21 passes through the opening and is electrically connected to the battery monomer 10. Specifically, the first sub-portion 2111 is electrically connected to the first electrode 113, and the second sub-portion 2112 is electrically connected to the second electrode 114.

[0080] As shown in Figure 5B and Figure 6 , the flow guide 211 includes a plurality of connecting arms 2115, which connect two adjacent battery monomers 10 in the second direction D2. Both ends of the connecting arm 2115 are provided with a second weak portion 2114. When the second weak portion 2114 at both ends of the connecting arm 2115 is broken by the valve opening gas flow, the connecting arm 2115 will fall between the two adjacent battery monomers 10, which is easy to cause the shell 12 of the two adjacent battery monomers 10 to be conductive, causing a short circuit of the circuit.

[0081] To this end, a groove 221 corresponding to the connecting arm 2115 can be arranged on the bracket 22. When the connecting arm 2115 falls off, the connecting arm 2115 is carried by the bottom of the groove 221, so it cannot fall between the two adjacent battery monomers 10.

[0082] The integrated busbar 20 can further include a flexible circuit board 23 for collecting and transmitting voltage data. The flexible circuit board 23 is arranged on the side surface of the bracket 22 away from the battery monomer 10, and the flexible circuit board 23 is located at the edge of the bracket 22. The flexible circuit board 23 can be connected to the busbar 21 through a plurality of connecting pieces 231. One end of the connecting piece 231 is connected to the edge of the flexible circuit board 23, and the other end is connected to the busbar 21. The material of the connecting piece 231 can be nickel, but is not limited thereto. One connecting piece 231 is connected to the first busbar end 212, and the other connecting piece 231 is connected to the second busbar end 213. A plurality of connecting pieces 231 are connected to a plurality of busbars 211 one by one. Through the above arrangement, the grouping of the integrated busbar 20 can be made simpler, and the production efficiency is higher.

[0083] In an embodiment, the pressure relief valve 111 is in the shape of a ring, and the through hole 31 is a circular hole. The diameter of the through hole 31 is greater than the outer diameter of the pressure relief valve 111 and less than the outer diameter of the cylindrical battery monomer 10. The diameter of the through hole 31 is greater than the outer diameter of the pressure relief valve 111, so that the pressure relief valve 111 can pass through the through hole 31.

[0084] The diameter of the through hole 31 is less than the outer diameter of the cylindrical battery monomer 10, so that the fireproof belt 30 can cover at least the gap between the adjacent two battery monomers 10, preventing the conductive objects in the gas flow sprayed by the opened pressure relief valve 111 from falling between the adjacent two battery monomers 10, causing short circuit.

[0085] Optionally, the battery monomer 10 is a cylindrical battery or a square electrode, but is not limited thereto.

[0086] In a second aspect, as shown in the drawings, the embodiments of the present application provide a battery pack 2, which includes the above-mentioned battery module 1. Figure 8

[0087] In an embodiment, the battery pack 2 can include a plurality of battery modules 1 and a battery box, and the plurality of battery modules are placed in the battery box.

[0088] The above describes the embodiments of the present application in detail. The specific examples are applied to the principles and implementation modes of the present application, and the above embodiment descriptions are only used to help understand the method and core idea of the present application. Meanwhile, for those skilled in the art, according to the idea of the present application, the specific implementation mode and application range can be changed. In summary, the content of the specification should not be understood as a limitation of the present application.​

Claims

1. A battery module (1), characterized in that The application relates to a battery pack. The battery pack comprises: a plurality of battery cells (10), each of which is provided with a pressure relief valve (111) on the top; an integrated busbar (20) arranged on one side of the top of the plurality of battery cells (10); 2. The battery module (1) according to claim 1, characterized in that a fireproof belt (30) arranged on the side of the integrated busbar (20) away from the battery cells (10), wherein the fireproof belt (30) is provided with a through hole (31) corresponding to each pressure relief valve (111).

3. The battery module (1) according to claim 2, characterized in that The through hole (31) is provided with an insulating part (32), and the edge of the insulating part (32) is connected to the side wall of the through hole (31) through a weak structure (34).

4. The battery module (1) according to claim 1, characterized in that The weak structure (34) comprises a plurality of connecting ribs arranged at intervals along the edge of the insulating part (32).

5. The battery module (1) according to claim 1, characterized in that One side surface of the fireproof belt (30) is provided with an insulating film (33), the insulating film (33) covers each through hole (31), and the thickness of the insulating film (33) is smaller than the thickness of the fireproof belt (30).

6. The battery module (1) according to any one of claims 1 to 5, characterized in that The pressure relief valve (111) is in the shape of a ring, the through hole (31) is a circular hole, the diameter of the through hole (31) is greater than the outer diameter of the pressure relief valve (111) and smaller than the outer diameter of the battery cell (10).

7. The battery module (1) according to claim 6, characterized in that The battery cell (10) comprises a first electrode (113) and a second electrode (114) arranged on the same end surface of the battery cell (10) as the pressure relief valve (111), the first electrode (113) surrounds the pressure relief valve (111), and the pressure relief valve (111) surrounds the second electrode (114).

8. The battery module (1) according to claim 7, characterized in that The integrated busbar (20) comprises a busbar (21) comprising a plurality of flow guide bars (211) arranged in a first direction, the flow guide bars (211) are connected in series to the plurality of battery cells (10), the flow guide bars (211) comprise a first subpart (2111) connected to the first electrode (113), a second subpart (2112) connected to the second electrode (114), and a first weak part (2113) connecting the first subpart (2111) and the second subpart (2112), the through hole (31) exposes the second subpart (2112) and at least part of the first weak part (2113), the cross-sectional area of the first subpart (2111) and the second subpart (2112) is greater than that of the first weak part (2113), and the second subpart (2112) is arranged in connection with the second electrode (114). The flow guide bar (211) comprises a second weak part (2114) connecting two adjacent second subparts (2112), and the through hole (31) exposes the second weak part (2114), wherein the cross-sectional area of the second subpart (2112) is greater than that of the second weak part (2114).

9. The battery module (1) according to claim 8, characterized in that The integrated busbar (20) comprises a support (22) arranged between the busbar (21) and the battery cell (10), the support (22) is used for carrying the busbar (21), the flow guide bar (211) comprises a connecting arm (2115), two ends of the connecting arm (2115) are connected to a second weak part (2114) respectively, and the support (22) is provided with a groove (221), and the connecting arm (2115) is arranged in the groove (221).

10. A battery pack (2) characterized by, A battery module (1) comprising any one of claims 1 to 9.

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