Battery module and preparation method thereof

Abstract

The invention relates to the technical field of batteries, in particular to a battery module and a preparation method thereof. The battery module comprises a battery cell body, a Breaker assembly and an insulating shell, a tab group is arranged at one end of the battery cell body, the tab group comprises a first tab and a second tab, and first insulating gummed paper is arranged at one end, close to the tab group, of the battery cell body; the Breaker assembly is adhered to the first insulating gummed paper, the Breaker assembly comprises a fuse, a first connecting piece and a second connecting piece, the first connecting piece and the second connecting piece are arranged at the two ends of the fuse, the fuse is adhered to the first insulating gummed paper, the free end of the first connecting piece is connected with the free end of the first tab, and the first connecting piece and the first tab are bent in the length direction of the first connecting piece. The bent first connecting piece, the bent first tab, the fuse and the second connecting piece form a Breaker reinforcing body; and the insulating shell is arranged on the battery cell body in an injection molding manner and wraps the Breaker reinforcing body. Therefore, the bimetallic strip of the Breaker assembly is not afraid of high-temperature and high-humidity use environment and is not oxidized to fail any more, and the use performance and the service life of the battery module are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a battery module and a preparation method thereof. Background Art

[0002] As the capacity, charge and discharge rate, and temperature of lithium batteries increase, people are more concerned about the safety performance of lithium batteries. For safety reasons, the battery cells need to be connected to a breaker component (fuse) for safety protection.

[0003] When setting the Breaker component on the battery, use double-sided tape to stick the Breaker component to the top sealing edge of the battery cell, then use a laser welding machine to weld the input end of the Breaker component to the positive (AL) tab of the battery cell, and finally use insulating paper to insulate and fix it again. The existing method of fixing the Breaker component often fails in viscosity during use, causing the Breaker component to warp up, which is easily damaged when subjected to external force, and the Breaker component will puncture the battery cell when the battery cell falls, causing the battery cell to fail. At the same time, when the battery is used in a high temperature and high humidity environment, the bimetallic strip in the Breaker component will oxidize and fail, affecting the performance and life of the battery. Summary of the invention

[0004] The technical problem to be solved by the embodiments of the present invention is to provide a battery module and a preparation method thereof, so as to solve the problem that the way of fixing the breaker assembly in the prior art often fails in viscosity during use, causing the breaker assembly to warp and be easily damaged when subjected to external force, and the breaker assembly will puncture the battery cell when the battery cell falls, causing the battery cell to fail. At the same time, when the battery is used in a high temperature and high humidity environment, the bimetallic strip in the breaker assembly will oxidize and fail, affecting the performance and life of the battery.

[0005] The present invention discloses a battery module, comprising a battery cell body, a breaker assembly and an insulating shell, wherein a tab group is arranged at one end of the battery cell body, the tab group comprises a first tab and a second tab arranged oppositely, and a first insulating tape is arranged at one end of the battery cell body close to the tab group; the breaker assembly is bonded to the first insulating tape, the breaker assembly comprises a fuse, a first connector and a second connector arranged at both ends of the fuse, the fuse is located on a side close to the battery cell body and bonded to the first insulating tape, the free end of the first connector is connected to the free end of the first tab, the first connector and the first tab are bent at a first notch along the length direction of the first connector, the bent first connector, the bent first tab, the fuse and a part of the second connector form a breaker reinforcement body; the insulating shell is injection molded on the battery cell body, and wraps the first tab, the first connector, the fuse and a part of the second connector of the breaker reinforcement body.

[0006] Optionally, a first notch is formed on the first connecting member, and the first connecting member and the first electrode tab are bent along the first notch in the length direction of the first connecting member.

[0007] Optionally, when the Breaker component is a U-shaped structure, the Breaker component is located between the first pole lug and the second pole lug, a gap is maintained between the second pole lug and the second connecting member, and the first insulating tape faces one side of the first pole lug.

[0008] Optionally, when the Breaker assembly is a return-to-original structure, the first insulating tape is opposite to one side of the first pole ear and one side of the second pole ear, a second notch is formed on the second connecting piece, and the second connecting piece is bent at the second notch along the extension direction of the second connecting piece to make the second connecting piece bend back, and the insulating shell also wraps part of the second pole ear.

[0009] Optionally, a groove is further provided on the insulating shell, and the groove is located at the top of the insulating shell.

[0010] Optionally, the wall thickness of the insulating shell is h1, and the value range of h1 is 0.4mm-4.5mm.

[0011] Optionally, in the rectangular structure of the insulating shell, the difference in wall thickness between every two adjacent side walls does not exceed 25%.

[0012] Optionally, a distance between an edge of the insulating shell close to the first pole lug and the first pole lug is h2, and a value range of h2 is 1.4 mm-6 mm.

[0013] The present invention also discloses a method for preparing a battery module, comprising:

[0014] Take a cell body, one end of which is provided with a tab group, the tab group includes a first tab and a second tab that are arranged opposite to each other, and a first insulating adhesive paper is provided on a side of the cell body close to the tab group, the first insulating adhesive paper is directly opposite to a side of the first tab;

[0015] Take a Breaker assembly, which is a U-shaped structure, and set the Breaker assembly between the first pole lug and the second pole lug. The Breaker assembly includes a fuse, a first connector and a second connector arranged at both ends of the fuse, and the fuse is bonded to the first insulating tape. A first notch is formed on the first connector, and a free end of the first connector and a free end of the first pole lug are welded;

[0016] Bend the first connecting member and the first tab at the first notch along the length direction of the first connecting member;

[0017] An injection-molded insulating shell is arranged at one end of the Breaker assembly on the battery body, and the insulating shell wraps the first pole ear, the first connecting piece, the fuse and part of the second connecting piece.

[0018] The present invention also discloses a method for preparing a battery module, comprising:

[0019] Take a cell body, one end of which is provided with a tab group, the tab group including a first tab and a second tab, and a first insulating adhesive tape is provided on a side of the cell body close to the tab group, the first adhesive tape is directly opposite to a side of the first tab and a side of the second tab;

[0020] Take a Breaker component, the Breaker component is a return-to-original structure, the Breaker component includes a fuse, a first connector and a second connector provided at both ends of the fuse, the fuse is bonded to the first insulating tape, the free end of the first connector and the free end of the first pole ear are welded, the first connector is provided with a first notch, the second connector extends along the length direction of the battery body to the outside of the battery body, and the second connector is provided with a second notch;

[0021] Bend the first connecting member and the first tab at the first notch along the length direction of the first connecting member;

[0022] along the extension direction of the second connecting member, bending the second connection at the second notch so that the second connection is bent back;

[0023] An injection-molded insulating shell is disposed at one end of the breaker assembly on the battery body, and the insulating shell wraps the first pole lug, the first connecting piece, the fuse, part of the second connecting piece and part of the second pole lug.

[0024] Compared with the prior art, the battery module and the preparation method thereof provided by the embodiments of the present invention have the following beneficial effects:

[0025] The setting of the Breaker component can protect the battery body from overload and overheating, and ensure the safety and reliability of the battery body. In the process of setting the Breaker component on the battery body, a first insulating tape is set at one end of the battery body close to the pole ear group, and the fuse is pre-fixed on the battery body through the first insulating tape. The free end of the first connector and the free end of the first pole ear are connected, and the first connector and the first pole ear are bent along the length direction of the first connector. The bent first connector, the bent first pole ear, the fuse and part of the second connector form a Breaker reinforcement body, and a Breaker reinforcement body is set on the battery body. An insulating shell is injection-molded at one end of the Breaker component, and the insulating shell wraps the first pole ear, the first connecting piece and part of the second connecting piece of the Breaker reinforcement, effectively encapsulating the Breaker component and the battery cell body as one, thereby enhancing the mechanical strength of the Breaker component, making the Breaker component less likely to be damaged by external forces, and also preventing the Breaker component from piercing the battery cell body when the battery module falls, and effectively isolating the Breaker component from the external environment, so that the bimetallic strip of the Breaker component is no longer afraid of oxidation failure in the high temperature and high humidity use environment, thereby ensuring the performance and life of the battery module. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments, in which:

[0027] Figure 1 It is a schematic diagram of the structure of a Breaker component of a U-shaped structure provided by an embodiment of the present invention;

[0028] Figure 2 is a schematic flow chart of a method for preparing a battery module provided by an embodiment of the present invention;

[0029] Figure 3 This is one of the structural schematic diagrams of a battery module provided by an embodiment of the present invention;

[0030] Figure 4 This is a second structural schematic diagram of a battery module provided by an embodiment of the present invention;

[0031] Figure 5 is a cross-sectional view of a battery module provided by one embodiment of the present invention;

[0032] Figure 6 is a schematic structural diagram of a Breaker component of a return-to-original-position structure provided by another embodiment of the present invention;

[0033] Figure 7 It is a bending diagram of a Breaker component of a return-to-origin structure provided by another embodiment of the present invention;

[0034] Figure 8 is a schematic flow chart of a method for preparing a battery module according to another embodiment of the present invention;

[0035] Fig. 9 is a structural schematic diagram of a battery module provided by another embodiment of the present invention;

[0036] Fig.10 is a cross-sectional view of a battery module provided by another embodiment of the present invention;

[0037] Fig.11 This is a test chart of an EDS test on a bimetallic strip of a Breaker component after the battery module provided by an embodiment of the present invention is stored under high temperature and high humidity (60° C., 90% RH) conditions for 1000 hours;

[0038] Fig.12 This is a state diagram of the bimetallic strip of the Breaker component after the battery module provided by the embodiment of the present invention is stored under high temperature and high humidity (60° C., 90% RH) conditions for 1000 hours;

[0039] Fig.13 This is an element analysis diagram of the bimetallic strip of the Breaker component after the battery module provided by an embodiment of the present invention is stored under high temperature and high humidity (60° C., 90% RH) conditions for 1000 hours;

[0040] Fig.14 yes Fig.13 The proportion of each element in the graph;

[0041] Fig.15 This is a test chart of the EDS test of the bimetallic strip of the Breaker component after the battery module obtained by fixing the Breaker component with conventional adhesive tape in the prior art was stored under high temperature and high humidity (60°C, 90% RH) conditions for 1000 hours;

[0042] Fig.16 This is a state diagram of the bimetallic strip of the Breaker component after the battery module obtained by fixing the Breaker component with conventional adhesive tape in the prior art is stored under high temperature and high humidity (60°C, 90% RH) conditions for 1000 hours;

[0043] Fig.17This is an elemental analysis diagram of the bimetallic strip of the Breaker component after the battery module obtained by fixing the Breaker component with conventional adhesive tape in the prior art is stored under high temperature and high humidity (60°C, 90% RH) conditions for 1000 hours;

[0044] Fig.18 yes Fig.17 The proportion of each element in the diagram.

[0045] The reference numerals in the figures are:

[0046] 10. Battery cell body; 110. First pole ear; 111. First insulating tape; 120. Second pole ear; 20. Breaker assembly; 210. Fuse; 220. First connector; 2201. First notch; 2202. Second notch; 230. Second connector; 30. Insulating shell; 301. Groove. DETAILED DESCRIPTION

[0047] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. Now, in conjunction with the accompanying drawings, the preferred embodiments of the present invention are described in detail.

[0048] An embodiment of the present invention provides a battery module, such as Figures 1 to 10 As shown, the battery cell body 10, the breaker assembly 20 and the insulating shell 30 are included. A tab group is provided at one end of the battery cell body 10. The tab group includes a first tab 110 and a second tab 120 that are arranged opposite to each other. A first insulating adhesive tape 111 is provided at one end of the battery cell body 10 close to the tab group. The breaker assembly 20 is bonded to the first insulating adhesive tape 111. The breaker assembly 20 includes a fuse 210, a first connector 220 and a second connector 230 that are arranged at both ends of the fuse 210. The fuse 210 is located close to the battery cell body 10 and is connected to the first insulating adhesive tape 111. The adhesive tape 111 is bonded, the free end of the first connector 220 is connected to the free end of the first pole ear 110, and the first connector 220 and the first pole ear 110 are bent at the first notch 2201 along the length direction of the first connector 220, and the bent first connector 220, the bent first pole ear 110, the fuse 210 and part of the second connector 230 form a Breaker reinforcement body; the insulating shell 30 is injection molded on the battery body 10, and wraps the first pole ear 110, the first connector 220, the fuse 210 and part of the second connector 230 of the Breaker reinforcement body.

[0049] The setting of the Breaker component 20 can protect the battery body 10 from the influence of overload and overheating, and ensure the safety and reliability of the battery body 10. In the process of setting the Breaker component 20 on the battery body 10, a first insulating tape 111 is set at one end of the battery body 10 close to the pole ear group, and the fuse 210 is pre-fixed on the battery body 10 through the first insulating tape 111. The free end of the first connector 220 and the free end of the first pole ear 110 are connected, and the first connector 220 and the first pole ear 110 are bent along the length direction of the first connector 220. The bent first connector 220, the bent first pole ear 110, the fuse 210 and part of the second connector 230 form a Breaker reinforcement body. An injection-molded insulating shell 30 is provided on one end of the Breaker component 20, and the insulating shell 30 wraps the first pole ear 110, the first connecting piece 220 and part of the second connecting piece 230 of the Breaker reinforcement, thereby effectively packaging the Breaker component 20 and the battery cell body 10 as a whole, thereby enhancing the mechanical strength of the Breaker component 20, making the Breaker component 20 less susceptible to damage due to external forces, and also preventing the Breaker component 20 from piercing the battery cell body 10 when the battery module falls, and effectively isolating the Breaker component 20 from the external environment, so that the bimetallic strip of the Breaker component 20 is no longer afraid of oxidation failure in the high temperature and high humidity use environment, thereby ensuring the use performance and life of the battery module.

[0050] As a preferred solution of this embodiment, a first notch 2201 is formed on the first connecting member 220 , and the first connecting member 220 and the first electrode tab 110 are bent along the first notch 2201 in the length direction of the first connecting member 220 .

[0051] The arrangement of the first notch 2201 facilitates operation so as to quickly bend the first connector 220 and the first electrode tab 110 .

[0052] In one embodiment of the present application, refer to Figures 1 to 3 When the Breaker assembly 20 is a U-shaped structure, the Breaker assembly 20 is located between the first pole ear 110 and the second pole ear 120 , a gap is maintained between the second pole ear 120 and the second connector 230 , and the first insulating tape 111 faces one side of the first pole ear 110 .

[0053] Among them, the above-mentioned Breaker component 20 is a U-shaped structure, which is mainly used in the battery body 10 with a large distance between the first pole ear 110 and the second pole ear 120. The Breaker component 20 is located between the first pole ear 110 and the second pole ear 120, and the Breaker component 20 does not contact the second pole ear 120. Therefore, it is only necessary to set the first insulating tape 111 on one side facing the first pole ear 110, so that the fuse 210 can be fixed on the battery body 10 through the first insulating tape 111.

[0054] In another embodiment of the present application, refer to Figures 6 to 8 When the Breaker assembly 20 is in a return-to-original structure, the first insulating tape 111 faces one side of the first pole ear 110 and the second pole ear 120, and a second notch 2202 is formed on the second connecting member 230. The second connecting member 230 is bent at the second notch 2202 along the extension direction of the second connecting member 230 so that the second connecting member 230 is bent back, and the insulating shell 30 also wraps a portion of the second pole ear 120.

[0055] Among them, the above-mentioned Breaker component 20 is a return-to-original structure, which is mainly used in the battery body 10 with a small distance between the first pole ear 110 and the second pole ear 120. The first insulating tape 111 is arranged on the side opposite to the first pole ear 110 and the second pole ear 120, so that the fuse 210 is fixed on the battery body 10 through the first insulating tape 111; the second connecting member 230 of the above-mentioned Breaker component 20 will extend to the outside of the battery body 10 along the width direction of the battery body 10. After the Breaker component 20 is installed, the second connecting member 230 is bent at the second notch 2202 along the extension direction of the second connecting member 230 to make the second connecting member 230 bend back, and the insulating shell 30 also wraps part of the second pole ear 120, ensuring that the insulating shell 30 fixes the Breaker component 20 on the battery body 10.

[0056] As a preferred solution of this embodiment, refer to Figure 3 The insulating shell 30 is also provided with a groove 301 , and the groove 301 is located at the top of the insulating shell 30 .

[0057] The setting of the above-mentioned groove 301 can reduce the cooling time during the injection molding process, and can avoid the side wall of the insulating shell 30 being too thick, and causing undesirable conditions such as shrinkage and deformation. The groove 301 is located at the top of the insulating shell 30 and between the first connecting member 220 and the second connecting member 230, which can ensure that the setting of the groove 301 on the insulating shell 30 will not interfere with the wrapping of the first connecting member 220 and the second connecting member 230 by the insulating shell 30, thereby ensuring the fit between the insulating shell 30 and the breaker assembly 20, strengthening the mechanical structure between the breaker assembly 20 and the battery cell body 10, and making the structure more solid and reliable, and not easily damaged by external forces.

[0058] As a preferred solution of this embodiment, refer to Figures 4 to 5 , Figures 9 and 10 The wall thickness of the insulating shell 30 is h1, and the value range of h1 is: 0.4mm-4.5mm.

[0059] Among them, the above-mentioned limitation on the wall thickness of the insulating shell 30 facilitates the flow of rubber during the injection molding process of the insulating shell 30, avoids defects such as insufficient rubber, lack of rubber, and difficulty in glue flow, and further improves the injection molding efficiency and molding effect of the insulating shell 30. The wall thickness h1 of the insulating shell 30 can be 0.4mm, 0.5mm, 0.8mm, 1mm, 2mm, 3mm, 4mm, and 4.5mm; the wall thickness of the insulating shell 30 in this embodiment is 0.5mm.

[0060] As a preferred solution of this embodiment, the insulating shell 30 is a rectangular structure, and the difference in wall thickness between every two adjacent side walls does not exceed 25%.

[0061] Among them, the above definition facilitates the flow of the rubber during the injection molding process of the insulating shell 30 , which can further improve the injection molding efficiency and molding effect of the insulating shell 30 .

[0062] As a preferred solution of this embodiment, refer to Figure 4 and Fig. 9 The distance between the edge of the insulating shell 30 close to the first pole tab 110 and the first pole tab 110 is h2, and the value range of h2 is 1.4 mm-6 mm.

[0063] The above spacing setting provides a 1 mm tolerance setting margin for the first pole ear 110 based on the wall thickness of the insulating shell 30, which facilitates the matching of the insulating shell 30 with the first pole ear 110 and the second pole ear 120. In this embodiment, the wall thickness of the insulating shell 30 is 0.5 mm, and the corresponding h2 is 1.5 mm.

[0064] In one embodiment of the present application, refer to Figure 4 The second pole tab 120 does not contact the insulating shell 30 , and therefore, no limitation is imposed on the second pole tab 120 .

[0065] In another embodiment of the present application, refer to Fig. 9 Part of the second pole lug 120 is also included in the insulating shell 30. Therefore, similarly, a tolerance setting margin of 1 mm is provided for the second pole lug 120. The distance between the edge of the insulating shell 30 close to the first pole lug 110 and the first pole lug 110 is h3, and h3 is 1.5 mm.

[0066] The present application also discloses a method for preparing a battery module. Figure 2 , the method comprises the following steps:

[0067] Take a cell body 10 , a pole lug group is arranged at one end of the cell body 10 , the pole lug group includes a first pole lug 110 and a second pole lug 120 arranged opposite to each other, a first insulating tape 111 is arranged on one side of the cell body 10 close to the first pole lug 110 , and the first insulating tape 111 is opposite to one side of the first pole lug 110 .

[0068] Take a Breaker component 20, which is a U-shaped structure. The Breaker component 20 is arranged between the first pole ear 110 and the second pole ear 120. The Breaker component 20 includes a fuse 210, a first connector 220 and a second connector 230 arranged at both ends of the fuse 210, and the fuse 210 is bonded to the first insulating tape 111. A first notch 2201 is formed on the first connector 220, and the free end of the first connector 220 and the free end of the first pole ear 110 are welded.

[0069] The first connecting member 220 and the first electrode tab 110 are bent at the first notch 2201 along the length direction of the first connecting member 220 .

[0070] An insulating shell 30 is injection-molded at one end of the breaker assembly 20 on the cell body 10 , and the insulating shell 30 encloses the first electrode tab 110 , the first connector 220 , the fuse 210 and part of the second connector 230 .

[0071] The present application also discloses a method for preparing a battery module. Figure 8 Take a cell body 10, a pole ear group is arranged at one end of the cell body 10, the pole ear group includes a first pole ear 110 and a second pole ear 120, and a first insulating tape 111 is arranged on the side of the cell body 10 close to the pole ear group, and the first insulating tape 111 is opposite to one side of the first pole ear 110 and one side of the second pole ear 120.

[0072] Take the Breaker component 20, which is a return-to-original structure. The Breaker component 20 includes a fuse 210, a first connector 220 and a second connector 230 provided at both ends of the fuse 210, the fuse 210 is bonded to the first insulating tape 111, the free end of the first connector 220 and the free end of the first pole ear 110 are welded, the first connector 220 is provided with a first notch 2201, the second connector 230 extends along the length direction of the battery cell body 10 to the outside of the battery cell body 10, and the second connector 230 is provided with a second notch 2202.

[0073] The first connecting member 220 and the first electrode tab 110 are bent at the first notch 2201 along the length direction of the first connecting member 220 .

[0074] The second connection is bent at the second notch 2202 along the extension direction of the second connection member 230 to make the second connection member 230 bend back.

[0075] An insulating shell 30 is injection-molded at one end of the breaker assembly 20 on the cell body 10 , and the insulating shell 30 encloses the first pole tab 110 , the first connector 220 , the fuse 210 , part of the second connector 230 and part of the second pole tab 120 .

[0076] The battery module obtained by the above battery module preparation method, during the preparation process, the setting of the Breaker component 20 can protect the battery cell body 10 from overload and overheating, and ensure the safety and reliability of the battery cell body 10. The setting of the insulating shell 30 effectively encapsulates the Breaker component 20 and the battery cell body 10 as one, thereby enhancing the mechanical strength of the Breaker component 20, making the Breaker component 20 less likely to be damaged by external forces, and also preventing the Breaker component 20 from piercing the battery cell body 10 when the battery module falls, and effectively isolating the Breaker component 20 from the external environment, so that the bimetallic strip of the Breaker component 20 is no longer afraid of oxidation failure in the high temperature and high humidity use environment, thereby improving the service life of the battery module.

[0077] Please refer to the attached Figures 11 to 18 , which are test diagrams of the bimetallic strips of the respective Breaker components of the battery module prepared by the preparation method of this embodiment and the battery module obtained by fixing the Breaker component with conventional adhesive tape in the prior art, both of which were stored under high temperature and high humidity (60°C, 90% RH) conditions for 1000 hours;

[0078] according to Fig.11 and Fig.15 It can be seen from the comparison that the bimetallic strip of the Breaker assembly 20 of the battery module of this embodiment has uniform element distribution, and the red and green parts are evenly distributed, indicating that the contents of oxygen and manganese are comparable. However, in the prior art, the bimetallic strip of the Breaker assembly of the battery module obtained by fixing the Breaker assembly with conventional adhesive tape has uneven element distribution, and it can be clearly seen that the distribution area of ​​the green part is larger than that of the red part, indicating that the content of oxygen is much larger than that of manganese, indicating that the oxidation degree of the bimetallic strip is relatively high.

[0079] according to Fig.12 and Fig.16It can be seen from the comparison that the surface of the bimetallic strip of the Breaker assembly 20 of the battery module of this embodiment is smooth and the bimetallic strip itself is not damaged. However, in the prior art, the bimetallic strip of the Breaker assembly of the battery module obtained by fixing the Breaker assembly with conventional adhesive tape has a large area of ​​powder on its surface, indicating that the surface of the bimetallic strip is oxidized.

[0080] according to Fig.13 , Fig.14 and Fig.17 and Fig.18 It can be seen from the comparison that the oxygen content in the bimetallic strip of the Breaker assembly 20 of the battery module of this embodiment is only 2.62%. However, in the prior art, the oxygen content in the bimetallic strip of the Breaker assembly of the battery module obtained by fixing the Breaker assembly with conventional adhesive tape is 26.86%, indicating that the surface of the bimetallic strip is severely oxidized.

[0081] The battery module prepared above for this embodiment and the battery module obtained by fixing the Breaker component with conventional adhesive tape in the prior art, after being stored for 1000 hours under high temperature and high humidity conditions (60°C, 90% RH), the bimetallic strip of the Breaker component 20 of this embodiment is not afraid of oxidation failure due to the high temperature and high humidity use environment, thereby improving the overall performance and service life of the battery module.

[0082] In this embodiment, the material of the insulating shell 30 includes polyamide, and the insulating shell 30 is formed by low-temperature injection molding.

[0083] Polyamide has the following advantages: it has strong mobility and low molding temperature. Its strong fluidity can improve production efficiency, enable faster glue injection, and is not prone to glue shortage. It also has low molding temperature and fast cooling speed, so it can be cooled and molded quickly. It has strong viscosity and good thermal stability. Strong viscosity allows the glue to adhere better to the surface of the battery cell body 10, and good thermal stability is beneficial to the overall stability of the insulating shell 30 after molding. The insulating shell 30 is not easily deformed when the battery module is used and generates temperature rise. It has high dielectric strength and good flame retardancy. High dielectric strength can play an effective insulating role to avoid micro-short circuits between the Breaker component 20 and the battery cell, and the polyamide glue meets the UL94-V0 grade, which can meet the fire protection grade requirements of the battery module.

[0084] The insulating shell 30 is formed by low-temperature injection molding. This process is simple and easy to implement, which simplifies the process of the battery module preparation method of this embodiment and improves the production efficiency of the battery module.

[0085] Comparative Example:

[0086] A method for preparing a battery module is provided, which differs from the method for preparing a battery module of the above embodiment in that a first insulating tape is not provided on a side of a battery cell body close to a tab group, a breaker assembly is not pre-fixed, and other conditions remain unchanged to obtain a battery module.

[0087] The following influences occurred during the preparation of the battery module in the comparative example: the Breaker component was skewed and floated, resulting in obstruction of the flow of the rubber during the injection molding process.

[0088] The prepared battery module has defects such as lack of glue and white exposure.

[0089] After the obtained battery module was stored under high temperature and high humidity conditions (60°C, 90% RH) for 1000 hours, obvious oxidation occurred at the locations where the glue was missing and the white was exposed at the first and second pole ears. There was oxidized powder on the surface of the bimetallic strip of the Breaker component. The oxygen content of TDS elemental analysis was 17.93%, indicating that the surface of the bimetallic strip was severely oxidized.

[0090] It should be understood that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. For those skilled in the art, the technical solutions described in the above embodiments can be modified, or some of the technical features therein can be replaced by equivalents; and all these modifications and replacements should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A battery module, characterized in that: include: A cell body, wherein a tab group is disposed at one end of the cell body, the tab group comprises a first tab and a second tab that are disposed opposite to each other, and a first insulating adhesive tape is disposed at one end of the cell body close to the tab group; A Breaker component, the Breaker component is bonded to the first insulating tape, the Breaker component includes a fuse, a first connector and a second connector provided at both ends of the fuse, the fuse is located on a side close to the battery body and bonded to the first insulating tape, the free end of the first connector is connected to the free end of the first pole ear, the first connector and the first pole ear are bent along the length direction of the first connector, and the bent first connector, the bent first pole ear, the fuse and part of the second connector form a Breaker reinforcement body; An insulating shell is injection-molded on the battery cell body and wraps the first pole ear, the first connecting piece, the fuse and part of the second connecting piece of the Breaker reinforcement.

2. The battery module according to claim 1, characterized in that: A first notch is formed on the first connecting member, and the first connecting member and the first electrode tab are bent along the first notch in the length direction of the first connecting member.

3. The battery module according to claim 2, characterized in that: When the Breaker component is a U-shaped structure, the Breaker component is located between the first pole lug and the second pole lug, a gap is maintained between the second pole lug and the second connecting member, and the first insulating tape faces one side of the first pole lug.

4. The battery module according to claim 2, characterized in that: When the Breaker assembly is a return-to-original structure, the first insulating tape faces one side of the first pole ear and one side of the second pole ear, a second notch is formed on the second connecting piece, and the second connecting piece is bent at the second notch along the extension direction of the second connecting piece to make the second connecting piece bend back, and the insulating shell also wraps part of the second pole ear.

5. The battery module according to claim 3 or 4, characterized in that: The insulating shell is also provided with a groove, and the groove is located at the top of the insulating shell.

6. The battery module according to claim 3 or 4, characterized in that: The wall thickness of the insulating shell is h1, and the value range of h1 is 0.4mm-4.5mm.

7. The battery module according to claim 3 or 4, characterized in that: The insulating shell has a rectangular structure, and the difference in wall thickness between any two adjacent side walls does not exceed 25%.

8. The battery module according to claim 6, characterized in that: The distance between the edge of the insulating shell close to the first pole lug and the first pole lug is h2, and the value range of h2 is 1.4 mm-6 mm.

9. A method for preparing a battery module, characterized in that: include: Take a cell body, one end of which is provided with a tab group, the tab group includes a first tab and a second tab that are arranged opposite to each other, and a first insulating adhesive paper is provided at one end of the cell body close to the tab group, the first insulating adhesive paper is directly opposite to one side of the first tab; Take a Breaker assembly, which is a U-shaped structure, and set the Breaker assembly between the first pole lug and the second pole lug. The Breaker assembly includes a fuse, a first connector and a second connector arranged at both ends of the fuse, and the fuse is bonded to the first insulating tape. A first notch is formed on the first connector, and a free end of the first connector and a free end of the first pole lug are welded; Bend the first connecting member and the first tab at the first notch along the length direction of the first connecting member; An injection-molded insulating shell is arranged at one end of the Breaker assembly on the battery body, and the insulating shell wraps the first pole ear, the first connecting piece, the fuse and part of the second connecting piece.

10. A method for preparing a battery module, characterized in that: include: Take a cell body, one end of which is provided with a tab group, the tab group including a first tab and a second tab, and a first insulating adhesive paper is provided at one end of the cell body close to the tab group, the first insulating adhesive paper is directly opposite to one side of the first tab and one side of the second tab; Take a Breaker component, the Breaker component is a return-to-original structure, the Breaker component includes a fuse, a first connector and a second connector provided at both ends of the fuse, the fuse is bonded to the first insulating tape, the free end of the first connector and the free end of the first pole ear are welded, the first connector is provided with a first notch, the second connector extends along the length direction of the battery body to the outside of the battery body, and the second connector is provided with a second notch; Bend the first connecting member and the first tab at the first notch along the length direction of the first connecting member; along the extension direction of the second connecting member, bending the second connection at the second notch so that the second connection is bent back; An injection-molded insulating shell is disposed at one end of the breaker assembly on the battery body, and the insulating shell wraps the first pole lug, the first connecting piece, the fuse, part of the second connecting piece and part of the second pole lug.

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