Battery pack and assembly method

Abstract

The invention relates to the technical field of power batteries, in particular to a battery pack and an assembling method. The battery pack includes: a case; the battery cell group is mounted in the shell, the battery cell group comprises a battery cell, and the battery cell is provided with a pole end provided with a pole and an exhaust end provided with an anti-explosion valve; the first adhesive layer is filled in the shell so as to fix the pole end of the battery cell in the shell; and the second adhesive layer is located in the shell, the exhaust end of the battery cell is sleeved with the second adhesive layer, the second adhesive layer is provided with an avoiding part corresponding to the anti-explosion valve, and the second adhesive layer and the first adhesive layer are directly bonded and fixed or are bonded and fixed through a connecting adhesive layer located between the first adhesive layer and the second adhesive layer. The second adhesive layer is provided with an avoiding part corresponding to the anti-explosion valve, so that the second adhesive layer can be prevented from blocking the anti-explosion valve; in addition, the first adhesive layer and the second adhesive layer are arranged in a layered manner, so that different types of adhesives can be selected according to requirements and can be independently formed, the cost can be reduced, and the overall structural strength and safety of the battery pack can be improved.

Description

TECHNICAL FIELD

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

[0002] The battery cells inside the battery pack generally need to be fixed by filling with foaming glue. Especially when the battery cells are cylindrical battery cells, foaming glue needs to be used to integrally encapsulate in the box body of the battery pack and fill the gaps between the battery cells. The overall structural strength of the foaming glue is low, and when the glue foams, the glue is easy to overflow to the bottom of the explosion-proof valve of the battery cell, causing blockage of the explosion-proof valve. When the battery cell is in thermal runaway, the opening of the explosion-proof valve is affected, which easily leads to safety accidents. SUMMARY

[0003] The present application provides a battery pack and an assembling method to solve the technical problem that the explosion-proof valve is easily blocked by foaming glue, thereby improving safety.

[0004] To achieve the above object and other related objects, the present application provides a battery pack, which comprises: a shell; a battery cell group, which is installed in the shell and comprises battery cells, the battery cells having a pole column end provided with a pole column and an exhaust end provided with an explosion-proof valve; a first glue layer, which is filled in the shell to fix the pole column end of the battery cell in the shell; a second glue layer, which is located in the shell, at least part of the second glue layer being sleeved on the exhaust end of the battery cell and having a avoiding portion corresponding to the explosion-proof valve, the second glue layer being directly bonded and fixed with the first glue layer or being bonded and fixed with the first glue layer through a connecting glue layer located between the first glue layer and the second glue layer.

[0005] In an embodiment of the present application, the first glue layer and the second glue layer are bonded and fixed through the connecting glue layer, the first glue layer comprises foaming glue, the second glue layer comprises foaming glue, and the connecting glue layer comprises structural glue.

[0006] In an embodiment of the present application, the first glue layer and the second glue layer are bonded and fixed through the connecting glue layer, the first glue layer comprises foaming glue, the second glue layer comprises structural glue, and the connecting glue layer comprises structural glue.

[0007] In an embodiment of the present application, the shell comprises an upper box body and a bottom plate, the pole column end of the battery cell faces the upper box body, the battery cell group further comprises a bus bar assembly, the bus bar assembly is located between the pole column end of the battery cell and the upper box body and is electrically connected with the battery cell, and the exhaust end of the battery cell faces the bottom plate.

[0008] In an embodiment of the present application, the busbar assembly and the upper box are insulated by an insulating plate, at least part of the first adhesive layer fills between the insulating plate and the pole end of the battery cell and covers the pole and the busbar assembly.

[0009] In an embodiment of the present application, a third adhesive layer which insulates the battery cell group and the upper box is further filled between the battery cell group and the upper box, the third adhesive layer comprises a structural adhesive, and the third adhesive layer covers the pole and the busbar assembly and is connected with the first adhesive layer.

[0010] In an embodiment of the present application, part of the second adhesive layer is located between the bottom plate and the exhaust end of the battery cell and supports the exhaust end of the battery cell, and the second adhesive layer is provided with an exhaust passage corresponding to the explosion-proof valve.

[0011] In an embodiment of the present application, the battery pack further comprises a support plate, the second adhesive layer is fixed on the support plate, the support plate is located between the bottom plate and the exhaust end of the battery cell and supports the exhaust end of the battery cell, and the support plate is provided with an exhaust passage corresponding to the explosion-proof valve.

[0012] In an embodiment of the present application, the height of the battery cell is h1, the height of the battery cell covered by the first adhesive layer is h2, and 0.8h1≤h2

[0013] To achieve the above object and other related objects, the present application further provides an assembling method for assembling the battery pack as described above, comprising the following steps: The shell comprises an upper box and a bottom plate, and the upper box is inverted; The battery cell group is inverted and placed in the upper box, and the battery cell group further comprises a busbar assembly located between the pole end of the battery cell and the upper box The first adhesive layer is filled in the upper box to cover at least part of the battery cell so as to fix the pole end of the battery cell in the shell; The second adhesive layer is cured and formed to have a relief part corresponding to the explosion-proof valve of the exhaust end of the battery cell, the cured and formed second adhesive layer is sleeved on the exhaust end of the battery cell and is directly bonded and fixed with the first adhesive layer or is bonded and fixed through a connecting adhesive layer; The bottom plate covers the box opening of the upper box and is connected and locked with the upper box.

[0014] In an embodiment of the present application, before the step of placing the battery cell group into the upper box body in an inverted manner and the step of further comprising the busbar assembly between the pole end of the battery cell and the upper box body, the method further comprises the step of filling a third glue layer into the upper box body; in the step of placing the battery cell group into the upper box body in an inverted manner and the step of further comprising the busbar assembly between the pole end of the battery cell and the upper box body, the third glue layer insulates and separates the upper box body from the busbar assembly, and the third glue layer completely covers the busbar assembly and is suitable for bonding with the shell of the battery cell.

[0015] In an embodiment of the present application, before the step of placing the battery cell group into the upper box body in an inverted manner and the step of further comprising the busbar assembly between the pole end of the battery cell and the upper box body, the method further comprises the step of placing an insulating plate in the upper box body; in the step of placing the battery cell group into the upper box body in an inverted manner and the step of further comprising the busbar assembly between the pole end of the battery cell and the upper box body, the insulating plate insulates and separates the upper box body from the busbar assembly; in the step of filling the first glue layer into the upper box body to cover at least part of the battery cell and fix the pole end of the battery cell in the shell, at least part of the first glue layer is filled between the insulating plate and the pole end of the battery cell and covers the pole and the busbar assembly.

[0016] In an embodiment of the present application, the second glue layer is directly bonded and fixed with the first glue layer before the first glue layer is completely cured, or the second glue layer is bonded and fixed with the first glue layer through the connecting glue layer after the first glue layer is completely cured.

[0017] The present application has the following beneficial effects: the battery pack and the assembling method provided by the present application have the second glue layer with an avoiding part corresponding to the explosion-proof valve, which can avoid the second glue layer from blocking the explosion-proof valve; in addition, the first glue layer and the second glue layer are arranged in layers, which is convenient for selecting different types of glue and respectively independently forming according to the requirement, which is conducive to reducing the cost and improving the overall structural strength and safety of the battery pack. BRIEF DESCRIPTION OF DRAWINGS

[0018] The accompanying drawings, which are incorporated herein and form part of the specification, illustrate embodiments consistent with the present application and, together with the description, further serve to explain the principles behind the application. It is apparent that the accompanying 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 labor on the basis of these drawings.

[0019] In the drawings: Figure 1 The structural schematic diagram of the battery pack provided for the first embodiment of the present application; Figure 2 Fig. 1 is an exploded view of a battery pack according to an embodiment of the present application; Figure 1 Fig. 2 is a schematic view of an explosion of the battery pack according to an embodiment of the present application; Figure 3 Fig. 3 is a front view of the battery pack according to an embodiment of the present application; Figure 1 Fig. 4 is a schematic view of a partial B of the battery pack according to an embodiment of the present application; Figure 4 Fig. 5 is a schematic view of a partial C of the battery pack according to an embodiment of the present application; Figure 3 Fig. 6 is a sectional view of A-A of the battery pack according to an embodiment of the present application; Figure 5 Fig. 7 is a schematic view of a partial D of the battery pack according to an embodiment of the present application; Figure 4 Fig. 8 is a sectional view of B-B of the battery pack according to an embodiment of the present application; Figure 6 Fig. 9 is a sectional view of C-C of the battery pack according to an embodiment of the present application; Figure 3 Fig. 10 is a sectional view of a partial structure of the battery pack according to an embodiment of the present application; Figure 7 Fig. 11 is an exploded view of a partial structure of the battery pack according to an embodiment of the present application; Figure 8 Fig. 12 is a schematic view of a partial D of the battery pack according to an embodiment of the present application; Figure 7 Fig. 13 is a sectional view of a partial structure of the battery pack according to an embodiment of the present application; Figure 9 Fig. 14 is an exploded view of a partial structure of the battery pack according to an embodiment of the present application; Figure 10 Fig. 15 is a sectional view of a partial structure of the battery pack according to an embodiment of the present application; Figure 11 Fig. 16 is an assembly diagram of an embodiment of the assembly method according to the present application.

[0020] Reference signs are as follows: Housing 1, upper box body 11, top plate 111, side plate 112, bottom plate 12, cell group 2, cell 21, pole 211, explosion-proof valve 212, shell 213, busbar assembly 22, first adhesive layer 3, second adhesive layer 4, avoiding part 41, supporting part 42, connecting adhesive layer 5, third adhesive layer 6, insulating plate 7, supporting plate 8, exhaust passage 9. DETAILED DESCRIPTION

[0021] The present application is described in more detail by the following specific examples. Other advantages and effects of the present application can be easily understood by those skilled in the art from the disclosure herein. The present application can also be implemented or applied by different specific embodiments, and the details in the specification can be modified or changed based on different views and applications without departing from the spirit of the present application. The following embodiments and features in the embodiments can be combined with each other without conflict.

[0022] It is to be understood that the figures provided in the following embodiments are only schematic and that the dimensions of the various parts do not correspond exactly to one another but have been chosen for the clarity of presentation; that the embodiments presented are but examples and that many equivalents are possible.

[0023] In the following description, numerous specific details are discussed to provide a thorough understanding of the embodiments of the application. One of ordinary skill in the related art will recognize, however, that the application can be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, devices, and so forth are not shown or described in detail in order to avoid obscuring aspects of the application.

[0024] Please refer to Figures 1 to 7 , Figure 9 In some optional embodiments, the application provides a battery pack, which comprises a shell 1, a cell group 2, a first glue layer 3 and a second glue layer 4. In addition to the above components, the battery pack can further comprise a connecting glue layer 5 and / or an insulating plate 7 and / or a third glue layer 6 and / or a support plate 8. The cell group 2 is installed in the shell 1, and the cell group 2 comprises cells 21, each of which has a pole end provided with a pole 211 and an exhaust end provided with an explosion-proof valve 212. The first glue layer 3 is filled in the shell 1 to fix the pole end of the cell 21 in the shell 1. The cell group 2 comprises a plurality of cells 21 arranged in stacks, and at least part of the first glue layer 3 is filled in the gap between the cells 21 to fix the cells 21. The second glue layer 4 is located in the shell 1, and at least part of the second glue layer 4 sheaths the exhaust end of the cell 21 to fix the exhaust end of the cell 21. The second glue layer 4 has a relief 41 corresponding to the explosion-proof valve 212, which can avoid the explosion-proof valve 212 being blocked to affect the exhaust of the explosion-proof valve 212. The second glue layer 4 is directly bonded and fixed with the first glue layer 3 or is bonded and fixed with the first glue layer 3 through the connecting glue layer 5 located between the first glue layer 3 and the second glue layer 4.

[0025] Optionally, the shell 1 comprises an upper box 11 and a bottom plate 12, and the pole end of the cell 21 faces the upper box 11. The cell group 2 further comprises a busbar assembly 22, which is located between the pole end of the cell 21 and the upper box 11 and is electrically connected with the cell 21. The exhaust end of the cell 21 faces the bottom plate 12. Further, the upper box 11 comprises a top plate 111 and a side plate 112, and the pole end of the cell 21 faces the top plate 111. The busbar assembly 22 is located between the pole end of the cell 21 and the top plate 111. Part of the first glue layer 3 is filled between the side plate of the upper box 11 and the cell group 2, and part of the first glue layer 3 is filled in the gap between the cells 21.

[0026] Optionally, the battery cell 21 further has a shell 213; wherein the battery cell 21 comprises a cylindrical battery cell, and a plurality of cylindrical battery cells are arranged in multiple rows. It should be noted that in the present application, the arrangement direction of the multiple rows of cylindrical battery cells is the same as the width direction of the shell 1, that is, the X direction in the drawings; and the arrangement direction of the multiple cylindrical battery cells in each row of cylindrical battery cells is the same as the length direction of the shell 1, that is, the Y direction in the drawings.

[0027] Optionally, the first adhesive layer 3 and the second adhesive layer 4 are adhesively fixed through the connecting adhesive layer 5, the first adhesive layer 3 comprises foamed glue, the second adhesive layer 4 comprises foamed glue, and the connecting adhesive layer 5 comprises structural glue. The first adhesive layer 3 and the second adhesive layer 4 adopt foamed glue, which has the advantages of light weight and impact resistance, and is beneficial to reducing the weight of the overall structure and improving the impact resistance of the overall structure; the connecting adhesive layer 5 adopts structural glue, which is relatively hard after curing and forming, has a stable structure and is not easy to deform, and is beneficial to improving the connection stability of the first adhesive layer 3 and the second adhesive layer 4.

[0028] Optionally, the first adhesive layer 3 and the second adhesive layer 4 are adhesively fixed through the connecting adhesive layer 5, the first adhesive layer 3 comprises foamed glue, the second adhesive layer 4 comprises structural glue, and the connecting adhesive layer 5 comprises structural glue. The first adhesive layer 3 adopts foamed glue, which not only has light weight but also has elasticity and can resist impact, and is beneficial to reducing the weight of the overall structure and improving the impact resistance of the overall structure; the connecting adhesive layer 5 and the second adhesive layer 4 adopt structural glue, which is relatively hard after curing and has a stable structure, and is beneficial to the assembly of the second adhesive layer 4 and the battery cell group 2 after curing and forming, and to improving the connection stability of the first adhesive layer 3 and the second adhesive layer 4.

[0029] Optionally, the height of the battery cell 21 is h1, the height of the battery cell 21 covered by the first adhesive layer 3 is h2, and 0.8h1≤h2

[0030] The battery pack of the above embodiment has the second glue layer 4 corresponding to the exhaust end of the battery cell 21, which has the avoiding part 41 corresponding to the explosion-proof valve 212. The avoiding part 41 can avoid the explosion-proof valve 212 and avoid blocking the explosion-proof valve 212, which is beneficial to the smooth discharge of smoke by the explosion-proof valve 212 when the battery cell 21 of the battery cell group 2 has thermal runaway. In addition, the first glue layer 3 and the second glue layer 4 are arranged in layers, so that the first glue layer 3 and the second glue layer 4 can be filled or installed respectively, which is convenient for independent molding and flexible selection of suitable types of glue according to different installation positions, and is beneficial to improve the strength of the overall structure of the battery pack, improve safety, reduce weight, improve energy density and reduce cost.

[0031] Referring to Figure 2 and Figure 4 In some optional embodiments, the upper box body 11 is provided with an insulating plate 7, and the busbar assembly 22 is insulated and separated from the upper box body 11 by the insulating plate 7. At least part of the first glue layer 3 is filled between the insulating plate 7 and the pole end of the battery cell 21, and covers the pole 211 and the busbar assembly 22. The filling is simple and convenient, which is beneficial to simplify the assembly process and reduce the cost. Especially when the first glue layer 3 is foamed glue, it is also beneficial to reduce the weight of the overall structure, thereby improving the energy density of the battery pack.

[0032] Referring to Figure 7 and Figure 8 In some optional embodiments, the battery cell group 2 and the upper box body 11 are also filled with a third glue layer 6 which insulates and separates the battery cell group 2 and the upper box body 11. The third glue layer 6 includes structural glue, and the third glue layer 6 covers the pole 211 and the busbar assembly 22 and is connected with the first glue layer 3.

[0033] Optionally, at least part of the third glue layer 6 is located between the top plate 111 of the upper box body 11 and the busbar assembly 22, that is, the busbar assembly 22 and the pole end of the battery cell 21 can be bonded and fixed to the top plate 111 of the upper box body 11 by the third glue layer 6 and insulated and separated, without the need to set an insulating plate, which is beneficial to reduce the number of parts and reduce the weight.

[0034] Optionally, the third glue layer 6 is in contact with and bonded to the shell 213 of the battery cell 21, and the part of the third glue layer 6 in contact with the first glue layer 3 is bonded and fixed.

[0035] The battery pack of the above embodiment, the pole end of the battery cell 21 and the busbar assembly 22 are fixed by the independent third glue layer 6, which is convenient to select the appropriate type of glue according to the needs, especially the use of heat-conducting structural glue, which has good heat conductivity and is conducive to heat dissipation of the busbar assembly 22 and the pole 211; in addition, the heat-conducting structural glue has stable structure and is not easy to deform, and the busbar assembly 22 and the pole 211 are covered by the heat-conducting structural glue, which is conducive to avoiding the deformation of the busbar assembly 22 caused by the first glue layer 3 foaming, thereby avoiding the virtual welding or welding of the busbar assembly 22, and ensuring the stability and reliability of the overall structure.

[0036] Referring to Figures 2 to 6 In some optional embodiments, a part of the second glue layer 4 is located between the bottom plate 12 and the exhaust end of the battery cell 21 and supports the exhaust end of the battery cell 21, and the second glue layer 4 is provided with an exhaust passage 9 corresponding to the explosion-proof valve 212.

[0037] Optionally, the avoiding part 41 includes an opening matched with the exhaust end of the battery cell 21 provided with the explosion-proof valve 212, the exhaust end of the battery cell 21 extends into the opening corresponding thereto, the opening is in communication with the exhaust passage 9, and the aperture of the opening is larger than the width of the exhaust passage 9 in the width direction of the shell 1 so that the second glue layer 4 has a supporting part 42 supporting the exhaust end of the battery cell 21, the end wall of the exhaust end of the battery cell 21 is in contact with the supporting part 42, the supporting part 42 can support the battery cell 21, and the flue gas discharged by the explosion-proof valve 212 enters the exhaust passage 9 after passing through the opening and is discharged.

[0038] Optionally, the shape of the second glue layer 4 is matched with the exhaust end of the battery cell 21, and the second glue layer 4 is suitable for integral molding, for example, it can be pre-solidified and molded on the bottom plate 12 by a tool, and after solidification and molding, it is assembled with the exhaust end of the battery cell 21. Compared with directly filling the second glue layer 4 into the shell 1, pre-solidification and molding are conducive to avoiding overflow and blocking of the explosion-proof valve 212 during filling and molding of the second glue layer 4.

[0039] The battery pack of the above embodiment, the second glue layer 4 is sleeved on the exhaust end of the battery cell 21, or in other words, the second glue layer 4 is covered on the exhaust end of the battery cell 21, which is simple and convenient to install.

[0040] Referring to Figure 9 and Figure 10 In some optional embodiments, the battery pack further includes a supporting plate 8, the second glue layer 4 is fixed on the supporting plate 8, the supporting plate 8 is located between the bottom plate 12 and the exhaust end of the battery cell 21 and supports the exhaust end of the battery cell 21, and the supporting plate 8 is provided with an exhaust passage 9 corresponding to the explosion-proof valve 212.

[0041] Optionally, the second glue layer 4 is coated on the side of the support plate 8 facing the battery cell 21 and solidified to form, and then assembled with the exhaust end of the battery cell 21 after the solidification of the second glue layer 4. The second glue layer 4 is solidified to form and then assembled with the support plate 8 to the exhaust end of the battery cell 21, which is more advantageous than directly filling the second glue layer 4 into the shell 1 to avoid overflow and block the explosion-proof valve 212.

[0042] The battery pack of the above-mentioned embodiments has the second glue layer 4 solidified to form on the support plate 8 and connected with the support plate 8 as a whole, which is simple to manufacture and convenient to assemble.

[0043] Referring to Figure 1 , Figure 2 , Figure 4 , Figure 7 and Figure 11 In some optional embodiments, the present application provides an assembly method for assembling the battery pack in any of the above-mentioned embodiments, which comprises the following steps: inverting the upper box body 11 of the shell 1, i.e. placing the box opening of the upper box body 11 upward. Inverting the stacked and assembled battery cell group 2 and placing it into the upper box body 11, i.e. placing the pole end of the battery cell 21 downward and into the upper box body 11. Filling the first glue layer 3 into the upper box body 11 to cover at least part of the battery cell 21 to fix the pole end of the battery cell 21 in the shell 1. Solidifying the second glue layer 4 on the support plate 8 or directly on the bottom plate 12 to form a relief portion 41 corresponding to the explosion-proof valve 212 of the exhaust end of the battery cell 21, and then sleeving the solidified second glue layer 4 on the exhaust end of the battery cell 21 and directly bonding and fixing it with the first glue layer 3 or bonding and fixing it through the connecting glue layer 5. Covering the bottom plate 12 over the box opening of the upper box body 11 and locking it with the upper box body 11.

[0044] Optionally, when the battery cell group 2 is inverted and placed into the upper box body 11, foam can be used to position and support the battery cell 21 of the battery cell group 2 to prevent the battery cell 21 from deviating or tilting, thereby preparing for subsequent glue pouring.

[0045] Optionally, the second glue layer 4 can be pre-solidified to form a shape suitable for the exhaust end of the battery cell 21 through a tool, so as to form the relief portion 41 corresponding to the explosion-proof valve 212 and the exhaust passage 9, which is simple to form and is also advantageous to avoid blocking the explosion-proof valve 212. The second glue layer 4 is inverted and buckled to cover the exhaust end of the battery cell 21 after solidification, which is convenient to assemble.

[0046] Optionally, in the step of filling the first glue layer 3 into the upper box body 11 to cover at least part of the battery cell 21 to fix the pole end of the battery cell 21 in the shell 1, the first glue layer 3 is foaming glue, the foaming glue is filled into the upper box body 11 and flows into the gap between the battery cells 21, and the height h2 of the battery cell 21 covered by the foaming glue is not less than 80% of the overall height h1 of the battery cell 21.

[0047] Optionally, in a specific embodiment, before the step of placing the battery cell group 2 into the upper box 11 upside down, the method further comprises the step of filling the third glue layer 6 into the upper box 11. In the step of placing the battery cell group 2 into the upper box 11 upside down, the third glue layer 6 insulates and separates the upper box 11 from the busbar assembly 22, and the third glue layer 6 completely covers the busbar assembly 22 and is suitable for bonding with the outer shell 213 of the battery cell group 2, or the thickness of the third glue layer 6 is sufficient to cover the busbar assembly 22 and the pole end of the battery cell 21 and can be bonded and fixed with the outer shell 213 of the battery cell 21. In this embodiment, the battery cell group 2 is insulated and separated from the upper box 11 by the third glue layer 6, and there is no need to further set the insulating plate 7. Further, the third glue layer 6 is a heat-conducting structural glue, the heat-conducting structural glue is filled after the battery cell group 2 is placed upside down, and the heat-conducting structural glue covers the busbar assembly 22 and the pole 211 and contacts the outer shell 213 of the battery cell 21 of the battery cell group 2. The heat-conducting structural glue is stable after solidification, which can effectively avoid the busbar assembly 22 being lifted by the first glue layer 3 foaming during the subsequent filling of the first glue layer 3, thereby facilitating the avoidance of the virtual welding or the welding of the battery cell 21 caused by the busbar assembly 22 being lifted, and further facilitating the improvement of the stability and reliability of the overall structure.

[0048] Optionally, referring to Figure 11 In another specific embodiment, before the step of placing the battery cell group 2 into the upper box 11 upside down, the method further comprises the step of placing the insulating plate 7 in the upper box 11. In the step of placing the battery cell group 2 into the upper box 11 upside down, the insulating plate 7 insulates and separates the upper box 11 from the busbar assembly 22. And in the step of filling the first glue layer 3 into the upper box 11 to cover at least part of the battery cell 21 to fix the pole end of the battery cell 21 in the shell 1, at least part of the first glue layer 3 is filled between the insulating plate 7 and the pole end of the battery cell 21, and covers the pole 211 and the busbar assembly 22. In this embodiment, by setting the insulating plate 7, the third glue layer can be filled, which is beneficial to simplify the assembly process.

[0049] Optionally, the second glue layer 4 is directly bonded and fixed with the first glue layer 3 before the first glue layer 3 is completely solidified, or the second glue layer 4 is bonded and fixed with the first glue layer 3 through the connecting glue layer 5 after the first glue layer 3 is completely solidified.

[0050] The assembly method of the above-mentioned embodiments is simple and convenient, and the first glue layer 3 and the second glue layer 4 are arranged in layers to be assembled in sequence, which is beneficial to fill different glues at different positions, to ensure the reliability of the overall structure while reducing the cost, and to pre-solidify the second glue layer 4 and then assemble the battery cell group 2, so as to avoid blocking the explosion-proof valve 212 of the battery cell group 2 by directly filling the second glue layer 4, and to improve the reliability and safety of the product.

[0051] The battery pack and the assembling method, the first glue layer 3 and the second glue layer 4 are independently arranged, the type selection and the assembling mode of glue are more flexible, the reliability, the safety and the cost reduction of the battery pack are improved.

[0052] The above embodiments only illustrate the principles and effects of the present application, and are not used to limit the present application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes completed by those skilled in the art without departing from the spirit and technical idea disclosed by the present application should be covered by the claims of the present application.

Claims

1. A battery pack, characterized in that, include: case; A battery cell assembly, wherein the battery cell assembly is installed inside the housing, the battery cell assembly includes a battery cell, the battery cell having a terminal end with a terminal post and an exhaust end with an explosion-proof valve; A first adhesive layer is filled inside the housing to fix the terminal end of the battery cell inside the housing; The second adhesive layer is located inside the housing. At least a portion of the second adhesive layer is sleeved over the exhaust end of the battery cell and has a clearance portion corresponding to the explosion-proof valve. The second adhesive layer is directly bonded to the first adhesive layer or bonded to it through a connecting adhesive layer located between the first adhesive layer and the second adhesive layer.

2. The battery pack according to claim 1, characterized in that, The first adhesive layer and the second adhesive layer are bonded and fixed together by the connecting adhesive layer. The first adhesive layer includes expanding foam, the second adhesive layer includes expanding foam, and the connecting adhesive layer includes structural adhesive.

3. The battery pack according to claim 1, characterized in that, The first adhesive layer and the second adhesive layer are bonded and fixed together by the connecting adhesive layer. The first adhesive layer includes foam adhesive, the second adhesive layer includes structural adhesive, and the connecting adhesive layer includes structural adhesive.

4. The battery pack according to claim 2 or 3, characterized in that, The housing includes an upper casing and a bottom plate. The terminal end of the battery cell faces the upper casing. The battery cell assembly also includes a busbar assembly. The busbar assembly is located between the terminal end of the battery cell and the upper casing and is electrically connected to the battery cell. The exhaust end of the battery cell faces the bottom plate.

5. The battery pack according to claim 4, characterized in that, The busbar assembly is insulated from the upper housing by an insulating plate. At least a portion of the first adhesive layer fills the space between the insulating plate and the terminal of the battery cell, and covers the terminal and the busbar assembly.

6. The battery pack according to claim 4, characterized in that, A third adhesive layer, which insulates and separates the battery cell assembly from the upper housing, is also filled between the battery cell assembly and the upper housing. The third adhesive layer includes structural adhesive, and covers the terminal post and the bus assembly and is connected to the first adhesive layer.

7. The battery pack according to claim 4, characterized in that, A portion of the second adhesive layer is located between the base plate and the venting end of the battery cell, and supports the venting end of the battery cell. The second adhesive layer is provided with a venting channel corresponding to the explosion-proof valve.

8. The battery pack according to claim 4, characterized in that, The battery pack also includes a support plate, the second adhesive layer is fixed on the support plate, the support plate is located between the bottom plate and the exhaust end of the battery cell, and supports the exhaust end of the battery cell, and the support plate is provided with an exhaust channel corresponding to the explosion-proof valve.

9. The battery pack according to claim 2 or 3, characterized in that, The height of the battery cell is h1, and the height of the battery cell covered by the first adhesive layer is h2, where 0.8h1≤h2<h1.

10. An assembly method for assembling a battery pack as described in any one of claims 1 to 9, characterized in that, Includes the following steps: The housing includes an upper box and a bottom plate, with the upper box inverted; The battery cell assembly is placed upside down into the upper housing, and the battery cell assembly also includes a bus assembly located between the terminal end of the battery cell and the upper housing; The first adhesive layer is filled into the upper housing to cover at least a portion of the battery cell to fix the terminal end of the battery cell inside the housing; The second adhesive layer is cured and formed to form a clearance part corresponding to the explosion-proof valve of the vent end of the battery cell. The cured second adhesive layer is then fitted onto the vent end of the battery cell and directly bonded and fixed to the first adhesive layer or bonded and fixed through a connecting adhesive layer. The bottom plate is used to cover the opening of the upper box and is then connected and locked to the upper box.

11. The assembly method according to claim 10, characterized in that, Before the step of inverting the battery cell assembly into the upper housing, wherein the battery cell assembly further includes a bus assembly located between the terminal end of the battery cell and the upper housing, the method further includes the following steps: filling the upper housing with a third adhesive layer; in the step of inverting the battery cell assembly into the upper housing, wherein the battery cell assembly further includes a bus assembly located between the terminal end of the battery cell and the upper housing, the third adhesive layer insulates and separates the upper housing from the bus assembly, and the third adhesive layer completely covers the bus assembly and is adapted to be bonded to the outer casing of the battery cell.

12. The assembly method according to claim 10, characterized in that, Before the step of inverting the battery cell assembly into the upper housing, wherein the battery cell assembly further includes a bus assembly located between the terminal end of the battery cell and the upper housing, the method further includes the following steps: placing an insulating plate inside the upper housing; in the step of inverting the battery cell assembly into the upper housing, wherein the battery cell assembly further includes a bus assembly located between the terminal end of the battery cell and the upper housing, the insulating plate insulatingly separates the upper housing from the bus assembly; in the step of filling the upper housing with a first adhesive layer to cover at least a portion of the battery cell to fix the terminal end of the battery cell within the housing, at least a portion of the first adhesive layer fills between the insulating plate and the terminal end of the battery cell, and covers the terminal end and the bus assembly.

13. The assembly method according to claim 10, characterized in that, The second adhesive layer is directly bonded and fixed to the first adhesive layer before the first adhesive layer is fully cured, or the second adhesive layer is bonded and fixed to the first adhesive layer through the connecting adhesive layer after the first adhesive layer is fully cured.

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