Support tube, battery casing, battery, battery pack, and battery mounting method

Abstract

The present application provides a support tube, a battery casing, a battery, a battery pack, and a battery mounting method. The support tube is configured to be embedded in a jelly roll and to support the jelly roll. Thus, supporting the jelly roll by means of the support tube is beneficial for mitigating the problem of the jelly roll collapsing toward a middle position.

Description

Supporting tube, battery shell, battery, battery pack and mounting method of battery

[0001] The present application claims priority to Chinese Patent Application No. 202421551273.0, 202421551166.8, 202421551143.7 and 202410882140.X, filed on July 2, 2024, with the Chinese Patent Office, the contents of which are incorporated herein by reference in their entirety. TECHNICAL FIELD

[0002] The present application relates to the technical field of batteries, in particular to a supporting tube, a battery shell, a battery, a battery pack and a mounting method of a battery. BACKGROUND

[0003] In the related art, a battery generally includes a battery shell and a winding core located inside the battery shell. SUMMARY

[0004] However, the middle position of the winding core has an opening, and the winding core is prone to collapse towards the opening position during long-term cyclic operation of the battery, resulting in lithium precipitation in the central region of the battery and further causing safety accidents.

[0005] The present application provides a supporting tube configured to be embedded in a winding core and support the winding core.

[0006] The present application also provides a battery shell including a surrounding plate having a receiving cavity and a supporting tube located in the receiving cavity, the supporting tube being configured to contact a winding core.

[0007] The present application also provides a battery including a battery shell and an electrode assembly, the battery shell including a surrounding plate having a receiving cavity and a supporting tube located in the receiving cavity, the supporting tube being configured to contact a winding core. The electrode assembly is located in the mounting cavity of the battery shell and is sleeved on the supporting tube; the electrode assembly has a first electrode and a second electrode, the first electrode being electrically connected to a first output terminal of the battery shell, and the second electrode being electrically connected to a second output terminal of the battery shell.

[0008] The present application also provides a battery including a winding core and a supporting tube, the winding core being arranged around the supporting tube, the supporting tube being configured to contact the winding core.

[0009] The present application also provides a battery pack including the battery of any of the above embodiments.

[0010] The application further provides a battery mounting method, which comprises: ironing a center hole of a winding core to form an ironing hole part with a melting trace in a part of a diaphragm of the winding core around the center hole of the winding core; placing the winding core in a shell assembly; and inserting a support tube into the center hole of the winding core and making the support tube contact a side wall of the ironing hole part. Advantages

[0011] For the support tube provided by the application, the support tube can support the winding core, thereby being beneficial to improving the problem that the winding core is easy to collapse to the middle position. BRIEF DESCRIPTION OF DRAWINGS

[0012] FIG. 1 is a structural schematic view of a battery provided by an embodiment of the application;

[0013] FIG. 2 is a sectional view of FIG. 1;

[0014] FIG. 3 is a front view of a support tube according to an embodiment of the application;

[0015] FIG. 4 is a top view of the support tube according to an embodiment of the application;

[0016] FIG. 5 is a structural schematic view of an A area in FIG. 2;

[0017] FIG. 6 is a structural schematic view of a B area in FIG. 2;

[0018] FIG. 7 is a schematic view of relative position relationship between a second cover plate and the support tube according to the application;

[0019] FIG. 8 is a structural schematic view of a battery shell provided by an embodiment of the application;

[0020] FIG. 9 is a top view and a bottom view of the battery shell in FIG. 8;

[0021] FIG. 10 is a structural schematic view of another battery shell provided by an embodiment of the application;

[0022] FIG. 11 is a top view and a bottom view of the battery shell in FIG. 10;

[0023] FIG. 12 is a structural schematic view of a winding core according to an embodiment of the application;

[0024] FIG. 13 is a flow chart of a battery mounting method provided by an embodiment of the application;

[0025] FIG. 14 is a flow chart of step S30 according to an embodiment of the application. Embodiments of the application

[0026] The embodiments of the present application provide a support tube, as shown in FIG. 1 and FIG. 2, the support tube 20 is configured to be embedded in the winding core 30 and support the winding core 30. After being embedded in the winding core 30 and being in contact with the winding core 30, the support tube 20 can provide stable support for the winding core 30, thereby helping to improve the problem that the winding core 30 is easy to collapse to the middle position.

[0027] During the working process of the battery, a large amount of heat is generated, and the winding core 30 will expand after being heated, thereby forming a large extrusion between the winding core 30 and the support tube 20, which is easy to cause at least one of the support tube 20 and the winding core 30 to be damaged, thereby affecting the working of the battery.

[0028] In some embodiments, as shown in FIG. 2 to FIG. 4, the support tube 20 includes a tube body 24 and a sleeve 60, the sleeve 60 is wrapped outside the tube body 24, and the sleeve 60 is configured to be embedded in the winding core 30 and in contact with the winding core 30. After being in contact with the winding core 30, the support tube 20 as a whole provides stable support for the winding core 30, thereby helping to improve the problem that the winding core 30 is easy to collapse to the middle position.

[0029] The sleeve 60 includes a main body part 61 arranged around the tube body 24 and a protruding part 62 arranged at the side of the main body part 61 away from the tube body 24, and the protruding part 62 is configured to contact the winding core 30.

[0030] Through the above arrangement, the protruding part 62 of the sleeve 60 can provide good support for the winding core 30, thereby improving the risk of collapse of the winding core 30. In addition, the two sides of the protruding part 62 can also form recesses, so that when the protruding part 62 and the winding core 30 are extruded, a buffer space is provided for the interaction between the two, thereby improving the problem that the support tube 20 or the winding core 30 is structurally damaged due to excessive extrusion force.

[0031] In some examples, there is a groove 601 between the two adjacent protruding parts 62, and the groove 601 can provide a buffer space for the acting force between the support tube 20 and the winding core 30, thereby improving the problem that the acting force between the two is too large to cause rigid extrusion, and thereby improving the problem that the support tube 20 and the winding core 30 are damaged due to mutual extrusion.

[0032] For example, in the direction of the axis of the groove 601 away from the tube body 24, the opening area of the groove 601 gradually increases. In this way, the groove 601 can provide a larger buffer space for the acting force between the support tube 20 and the winding core 30, so as to improve the protection effect of the support tube 20 and the winding core 30.

[0033] In some examples, the side of the protrusion 62 away from the tube body 24 has a circular arc surface which is in contact with the winding core 30. This can improve the damage to the winding core 30 caused by the sharp contact position between the protrusion 62 and the winding core 30, and can also improve the reduction of the buffer space caused by the large contact surface between the protrusion 62 and the winding core 30.

[0034] For example, the circular arc surface can extend to the groove bottom of the groove 601.

[0035] In some examples, the extension direction of the protrusion 62 is consistent with the extension direction of the main body 61, and both of them extend along the axial direction of the tube body 24.

[0036] For example, the length of the protrusion 62 (i.e. the size of the protrusion 62 along the axial direction of the tube body 24) is the same as the length of the main body 61 (i.e. the size of the main body 61 along the axial direction of the tube body 24). In this way, the protrusion 62 and the winding core 30 can have a larger contact surface, thereby ensuring the stability of the support of the protrusion 62 to the winding core 30.

[0037] In some examples, the plurality of protrusions 62 are uniformly arranged on the circumferential side of the main body 61, thereby facilitating the improvement of the stability of the support of the protrusion 62 to the winding core 30.

[0038] In some embodiments, at least one of the main body 61 and the protrusion 62 is made of insulating material, thereby preventing the short circuit caused by the electrical connection between the support tube 20 and the positive and negative electrode sheets in the winding core.

[0039] In some examples, the main body 61 and the protrusion 62 are both made of insulating material, that is, the tube sleeve 60 is made of insulating material.

[0040] In some examples, the main body 61 and the protrusion 62 can be integrally formed.

[0041] In some embodiments, at least one of the main body 61 and the protrusion 62 is made of elastic material. In this way, the expansion of the electrode sheets (e.g. negative electrode sheets) in the winding core due to charging and the extrusion to the tube body 24 can be alleviated.

[0042] In some examples, the tube sleeve 60 can be made of elastic material. By using the elastic deformation of the tube sleeve 60, the extrusion force generated when the electrode sheets in the winding core expand due to charging can be effectively alleviated, thereby facilitating the extension of the cycle life of the lithium battery.

[0043] It should be noted that the material of the tube sleeve 60 is not specifically required or specially limited in the embodiments of the present application, as long as it has high temperature resistance and chemical stability, and can still be stably attached to the surface of the tube body 24 when the temperature inside the battery rises sharply, thereby preventing the direct contact between the tube body 24 and the electrode sheets in the winding core.

[0044] In some embodiments, as shown in FIG. 2, the tube body 24 is configured in a hollow shape, and the tube sleeve 60 is configured to transfer heat at the winding core 30, and the tube body 24 is configured to transfer heat at the tube sleeve 60.

[0045] In this way, heat at the winding core 30 can be transferred into the hollow inner cavity of the tube body 24 through the tube sleeve 60 and the tube body 24 in sequence, so that the heat dissipation effect of the winding core 30 can be improved, and the use performance of the winding core 30 can be improved.

[0046] In some embodiments, as shown in FIG. 2, at least one end of the tube body 24 is provided with an opening in communication with the outside. In this way, the hollow inner cavity 201 of the tube body 24 can be in communication with the outside of the battery, so that heat in the hollow inner cavity 201 can be discharged to the outside of the battery, and the heat dissipation efficiency of the battery 200 can be improved.

[0047] In some examples, the material of the tube body 24 can be metal, such as one of aluminum alloy, stainless steel, or nickel-plated SPCC, so that the tube body 24 has good support performance, heat dissipation performance, and corrosion resistance.

[0048] In some embodiments, the tube sleeve 60 is configured to expand in an electrolyte environment to make the protruding portion 62 contact the winding core 30.

[0049] In the assembly process of the battery, the support tube 20 with the tube sleeve 60 is first inserted into the center hole of the winding core 30, and there is a certain gap between the support tube 20 and the inner side wall of the winding core 30. Then electrolyte is injected into the battery, so that the winding core 30 is immersed in the electrolyte environment. The tube sleeve 60 expands after contacting the electrolyte and makes the protruding portion 62 contact the winding core 30, thereby providing a certain strength support to the winding core 30.

[0050] In the above manner, after the thicknesses of the tube sleeve 60 and the tube body 24 are reasonably set, the protruding portion 62 can be in contact with the winding core 30 after the expansion of the tube sleeve 60. In this way, on the one hand, the stability of the assembly of the support tube 20 and the winding core 30 can be ensured, and on the other hand, the problem that a large gap exists between the winding core 30 and the support tube 20 or the winding core 30 and the support tube 20 are too tightly pressed when the winding core 30 is directly wound around the support tube 20 can be improved.

[0051] In some examples, the tube sleeve 60 includes any one or a combination of at least two of polyether ester, propylene base, or vinyl base.

[0052] For example, the tube sleeve 60 can be made of polyoxymethylene (POM), polypropylene (PP) or polyethylene (PE) material; for another example, the tube sleeve 60 can also be made of TEPP material.

[0053] In some examples, a gap of 0.5mm to 1mm can be reserved between the winding core 30 and the support tube 20, and the initial maximum thickness of the tube sleeve 60 (i.e. the sum of the initial thickness of the main body part 61 and the initial thickness of the protruding part 62) can be set in the range of 0.25mm to 0.5mm, and the tube sleeve 60 is a limited swelling type tube sleeve, which can swell 2 to 3 times under the action of the components of the electrolyte solvent when it is immersed in the electrolyte. Therefore, the above gap can facilitate the insertion of the support tube 20 into the center hole of the winding core 30. After the swelling of the tube sleeve 60, it can well support the winding core 30.

[0054] It is worth noting that the initial thickness of the main body part 61 refers to the thickness of the main body part 61 in the absence of an electrolyte environment, the initial thickness of the protruding part 62 refers to the thickness of the protruding part 62 in the absence of an electrolyte environment, and the initial maximum thickness of the tube sleeve 60 refers to the maximum thickness of the tube sleeve 60 in the absence of an electrolyte environment.

[0055] In some examples, the swelling degree of the tube sleeve 60 is α, and the initial maximum thickness of the tube sleeve 60 is D, and the swelling amount of the tube sleeve 60 in the electrolyte environment is T, wherein 0

[0056] For example, α=2 and D=0.5mm, so the swelling amount of the tube sleeve 60 is 1mm. In this case, a gap of 1mm is reserved between the winding core 30 and the support tube 20, so that after the swelling of the tube sleeve 60 in the electrolyte environment, the swollen tube sleeve 60 can just contact the inner side wall of the winding core 30, thereby forming a good support for the winding core 30.

[0057] In some embodiments, as shown in FIG. 4, the initial thickness of the main body part 61 is t1, the initial thickness of the protruding part 62 is t2, and 0.5≤t2 / (t1+t2)≤0.8. Wherein the initial thickness t2 of the protruding part 62 is the distance between the protruding top point of the protruding part 62 and its bottom surface (i.e. the surface of the protruding part 62 contacting the main body part 61), and (t1+t2) is the initial maximum thickness of the tube sleeve 60.

[0058] By the above arrangement, the ratio of the initial thickness of the main body portion 61 to the initial maximum thickness of the sleeve 60 is between 0.5 and 0.8, so that the main body portion 61 has a relatively large thickness, thereby providing good support performance for the winding core 30. In addition, since the ratio of the initial thickness of the protrusion portion 62 to the initial maximum thickness of the sleeve 60 is small, the depth of the groove 601 is relatively small, thereby facilitating improvement of the problem that the winding core 30 is easily damaged when the winding core 30 is partially accommodated in the groove 601 due to the groove 601 having a too large depth when the winding core 30 is expanded.

[0059] In some examples, the swelling degree of the main body portion 61 and the protrusion portion 62 is the same as the swelling degree of the sleeve 60, so that the main body portion 61 and the protrusion portion 62 expand synchronously under the electrolyte condition.

[0060] In some embodiments, as shown in FIG. 2, the support tube 20 can be applied to the battery 200. The tube body 24 includes oppositely arranged first and second ends 21 and 22, respectively configured to connect the cover plate assembly 13 of the battery case 100.

[0061] In this way, by connecting the tube body 24 with the cover plate assembly and placing the winding core 30 in the battery case 100, the winding core 30 is supported by the tube body 24 and heat dissipation of the winding core 30 is facilitated, so that the structural stability and heat dissipation performance of the battery 200 are improved.

[0062] In some examples, the first end 21 and / or the second end 22 is provided with an opening in communication with the outside. For example, one of the first and second ends 21 and 22 is provided with an opening in communication with the outside; for another example, the first and second ends 21 and 22 are respectively provided with openings in communication with the outside.

[0063] In some examples, the hollow inner cavity 201 of the tube body 24 can be filled with a heat dissipation medium to improve the heat dissipation efficiency of the hollow inner cavity 201. For example, the heat dissipation medium can be a cooling liquid.

[0064] It should be noted that in the case of the heat dissipation medium being a cooling liquid, the cooling liquid is an insulating medium, thereby improving the problem that the two electrodes of the battery 200 are easily short-circuited.

[0065] In some embodiments, as shown in FIG. 2, the tube body 24 further includes an intermediate section 23, the first and second ends 21 and 22 being located at two ends of the intermediate section 23, and the outer diameters of the first and second ends 21 and 22 are both smaller than the outer diameter of the intermediate section 23.

[0066] In this way, the outer diameters of the first end 21 and the second end 22 are relatively small, which can reduce the welding area between the first end 21 and the second end 22 and the cover plate assembly 13 (e.g., the first cover plate 11 and the second cover plate 12), thereby facilitating the reduction of the opening pressure at the connection position of the first end 21 and the second end 22 and the cover plate assembly. In addition, the relatively small diameters of the first end 21 and the second end 22 also facilitate the smooth insertion of the support tube 20 into the middle cavity of the roll core 30.

[0067] In some examples, the thicknesses of the first end 21, the second end 22, and the middle section 23 are equal. In this case, the diameters of the openings corresponding to the first end 21 and the second end 22 (i.e., the inner diameters of the first end 21 and the second end 22) are smaller than the inner diameter of the middle section 23. In this way, when the heat emitted in the middle section 23 is discharged from the first end 21 or the second end 22, the airflow will speed up due to the decrease in the tube diameter, which facilitates the improvement of the heat dissipation efficiency of the support tube 20.

[0068] For example, at least one of the first end 21 and the second end 22 includes a variable-diameter section and a fixed section, the fixed section is connected to the middle section through the variable-diameter section, and the outer diameter of the fixed section is smaller than the outer diameter of the middle section.

[0069] For example, the first end 21, the second end 22, and the middle section 23 are integrally formed.

[0070] In some examples, along the axial direction of the support tube 20 (i.e., the axial direction of the tube body 24), the size of the sleeve 60 is equal to the size of the middle section 23, i.e., the length of the sleeve 60 is equal to the length of the middle section 23. In this way, the sleeve 60 can form a good coverage of the middle section 23. For example, the length of the main body 61 is equal to the length of the sleeve 60.

[0071] Some embodiments of the present application provide a battery shell, as shown in FIG. 1, the battery shell 100 includes the support tube 20 described in any of the above embodiments.

[0072] Due to the inclusion of the support tube 20, the battery shell 100 has all the technical effects of the support tube 20, which will not be repeated here.

[0073] In the related art, the battery shell 100 has a cover plate assembly, which is usually provided with output terminals to lead the positive and negative electrodes of the electrode assembly out of the protective shell. With the increase of the battery charging and discharging power, the heat generation usually also increases. Since the output terminals are the main output ports of the battery current, heat will be concentrated on the output terminals during the operation of the battery. The output terminals are connected to the electrodes of the electrode assembly, and if the heat cannot be effectively dissipated, the local temperature will be too high, which will affect the stability of the electrode assembly inside, thereby affecting the electrical performance and safety performance of the battery.

[0074] Based on this, the battery shell provided in the embodiments of the present application is shown in FIG. 1, FIG. 8 and FIG. 10. The battery shell 100 comprises a surrounding plate 10 having opposite third and fourth ends 102 and 103. The surrounding plate 10 is formed with a receiving cavity 111, and the extending direction of the receiving cavity 111 is towards the third and fourth ends 102 and 103, i.e. the surrounding plate 10 is of an open-end structure, so as to facilitate the assembly of other structures in the surrounding plate 10. Meanwhile, the surrounding plate 10 serves as a protective shell and can protect the structures located in the surrounding plate 10.

[0075] The battery shell 100 comprises a support tube 20 located in the receiving cavity 111. The support tube 20 is hollow and has a hollow inner cavity 201 extending towards the third and fourth ends 102 and 103 and being in communication with the outside, i.e. the support tube 20 is of a hollow tubular structure and is located in the surrounding plate 10. The support tube 20 and the surrounding plate 10 can be arranged in a concentric ring structure.

[0076] The outer surface of the support tube 20 and the inner surface of the surrounding plate 10 jointly form a mounting chamber 101 for mounting an electrode assembly 301. The support tube 20 is used for sleeving the electrode assembly 301, i.e. when the electrode assembly 301 is mounted into the battery shell 100, the electrode assembly 301 can be directly sleeved on the support tube 20, and the electrode assembly 301 is mechanically supported by the support tube 20, so as to avoid the internal collapse of the electrode assembly 301 due to the expansion of the electrode assembly 301 during the operation, and thus the reliability of the battery 200 as a whole is enhanced.

[0077] In addition, a large amount of heat is generated during the operation of the battery 200, and there is a certain temperature difference between the center temperature and the surface temperature of the battery 200. If the heat cannot be effectively dissipated in time, the internal local temperature of the electrode assembly 301 will be too high, which will cause the increase of the side reaction of the battery 200 and affect the electrical performance and safety performance of the battery 200. In the embodiments of the present application, the support tube 20 is of a hollow structure and is in communication with the outside. The electrode assembly 301 is directly sleeved on the support tube 20, and the material of the support tube 20 comprises a heat-conducting material (for example, the tube body 24 and the tube sleeve 60 of the support tube 20 are made of a heat-conducting material). The heat generated in the electrode assembly 301 can be diffused to the outside through the hollow inner cavity 201 of the support tube 20, so as to avoid the concentration of heat in the electrode assembly 301, and thus the stability of the overall performance of the battery 200 is ensured.

[0078] The battery housing 100 comprises a cover plate assembly 13 connecting the surrounding plate 10 and the support tube 20, and sealing the installation chamber 101, i.e. the cover plate assembly 13, the surrounding plate 10 and the support tube 20 jointly form a sealed installation chamber 101, and the electrode assembly 301 is located in the installation chamber 101 to avoid the influence of the external environment on the electrode assembly 301, thereby affecting the overall performance of the battery 200.

[0079] It should be noted that the cover plate assembly 13 only seals the installation chamber 101, and exposes the hollow inner cavity 201 to ensure the communication between the hollow inner cavity 201 and the outside, i.e. the cover plate assembly 13 forms an opening at the position corresponding to the hollow inner cavity 201, the outer edge of the cover plate assembly 13 is connected with the edge of the containing cavity 111, and the edge of the opening of the cover plate assembly 13 is connected with the edge of the hollow inner cavity 201, thereby forming a sealed installation chamber 101.

[0080] The battery housing 100 further comprises an output terminal assembly 40 installed on the cover plate assembly 13, and the output terminal assembly 40 comprises a first output terminal 41 and a second output terminal 42 insulated from each other, and the first output terminal 41 and the second output terminal 42 are respectively used for electrically connecting with two electrodes of the electrode assembly 301 located in the installation chamber 101, so as to realize the electrical connection between the electrode assembly 301 and the external circuit.

[0081] Among them, at least one of the first output terminal 41 and the second output terminal 42 is connected with one end of the support tube 20. That is, at least one of the first output terminal 41 and the second output terminal 42 is arranged at a position close to the hollow inner cavity 201 of the support tube 20, and the first output terminal 41 and the second output terminal 42 serve as the output terminals of the battery 200 as a whole, and heat will also be concentrated on them. By arranging them at a position close to the hollow inner cavity 201, the heat on the corresponding output terminals can also be diffused to the outside through the hollow inner cavity 201, and the output terminals are used for electrically connecting with the electrodes of the electrode assembly 301 in the installation chamber 101, thereby avoiding the concentration of heat on the electrodes of the electrode assembly 301, and thereby helping to improve the stability of the overall performance of the battery 200.

[0082] The battery shell 100 in the embodiment of the present application comprises a surrounding plate 10, a support pipe 20, a cover plate assembly 13 and an output terminal assembly 40. The surrounding plate 10 has opposite third and fourth ends 102 and 103. The surrounding plate 10 is formed with a receiving cavity 111, and the extending direction of the receiving cavity 111 is towards the third and fourth ends 102 and 103. The support pipe 20 is located in the receiving cavity 111 and is provided with a hollow inner cavity 201. The extending direction of the hollow inner cavity 201 is towards the third and fourth ends 102 and 103. The hollow inner cavity 201 is in communication with the outside. The outer surface of the support pipe 20 and the inner surface of the surrounding plate 10 jointly form a mounting cavity 101 for mounting an electrode assembly 301. The support pipe 20 is used for sleeving the electrode assembly 301. The material of the support pipe 20 comprises a heat-conducting material. The cover plate assembly 13 connects the surrounding plate 10 and the support pipe 20. The cover plate assembly 13 seals the mounting cavity 101. The output terminal assembly 40 is arranged on the cover plate assembly 13. The output terminal assembly 40 comprises first and second output terminals 41 and 42 which are insulated from each other. At least one of the first and second output terminals 41 and 42 is connected to one end of the support pipe 20. In the present application, the hollow structure of the support pipe 20 is formed in the battery shell 100 and is in communication with the outside. At the same time, at least one output terminal is connected to one end of the support pipe 20. When the battery shell 100 is applied to a battery 200, the heat generated can be dissipated to the outside through the hollow inner cavity 201 of the support pipe 20. Therefore, the heat can be prevented from being concentrated on the output terminal, and the heat dissipation effect of the output terminal is improved.

[0083] In some embodiments, as shown in FIGS. 8 and 10, the cover plate assembly 13 comprises first and second cover plates 11 and 12. The first cover plate 11 connects the third end 102 of the surrounding plate 10 and the support pipe 20. The second cover plate 12 connects the fourth end 103 of the surrounding plate 10 and the support pipe 20. That is, the cover plate assembly 13 comprises the first and second cover plates 11 and 12 which are respectively located at the third and fourth ends 102 and 103 of the surrounding plate 10. The first and second cover plates 11 and 12 seal the mounting cavity 101. At least one of the first and second cover plates 11 and 12 is integrally formed with the surrounding plate 10.

[0084] The first output terminal 41 is installed on the first cover plate 11 and connected to one end of the support tube 20, and the second output terminal 42 is installed on the first cover plate 11 or the second cover plate 12, that is, the first output terminal 41 is installed near the hollow inner cavity 201 of the support tube 20, and the second output terminal 42 can be installed on the same cover plate or different cover plates as the first output terminal 41. By installing the first output terminal 41 near the hollow inner cavity 201 of the support tube 20, the heat on the first output terminal 41 can be diffused to the outside through the hollow inner cavity 201, and the first output terminal 41 is used to be electrically connected to one of the electrode assemblies 301 in the installation chamber 101, so as to avoid the concentration of heat on the electrode, thereby helping to improve the stability of the overall performance of the battery 200.

[0085] In some embodiments, the first output terminal 41 extends along the circumference of the support tube 20 in a ring shape, that is, the first output terminal 41 is located on the first cover plate 11 and surrounds the support tube 20, and surrounds a central hole, and the central hole is in communication with the hollow inner cavity 201 of the support tube 20. This kind of structure setting mode is helpful to increase the heat dissipation area between the first output terminal 41 and the hollow inner cavity 201 of the support tube 20, thereby helping to further improve the heat dissipation effect of the first output terminal 41.

[0086] In other embodiments, the first output terminal 41 is integrally formed with the first cover plate 11, that is, the first output terminal 41 and the first cover plate 11 are one body. The first cover plate 11 is partially protruded away from the installation chamber 101 and forms the first output terminal 41, and the first output terminal 41 is connected to the support tube 20, that is, the first output terminal 41 is a part of the first cover plate 11, and the first cover plate 11 is connected to the support tube 20 through the first output terminal 41, thereby helping the heat generated on the first output terminal 41 to be directly transmitted to the support tube 20 and dissipated through the hollow inner cavity 201 of the support tube 20. In addition, by setting the first output terminal 41 and the first cover plate 11 as one body, it is also helpful to simplify the overall structure of the battery shell 100, thereby simplifying the assembly process of the battery shell 100 and improving the production efficiency.

[0087] In some embodiments, the second output terminal 42 is mounted on the second cover plate 12, and the second output terminal 42 is connected to the other end of the support tube 20, and the material of the support tube 20 includes an insulating and heat-conducting material, that is, the first output terminal 41 and the second output terminal 42 are respectively mounted on different cover plates, and the second output terminal 42 is also arranged at a position close to the hollow inner cavity 201 of the support tube 20 but is not electrically connected to the support tube 20, so that the heat on the second output terminal 42 can also be diffused to the outside through the hollow inner cavity 201, and the second output terminal 42 is used to be electrically connected to another electrode of the electrode assembly 301 in the mounting chamber 101, so as to avoid the concentration of heat on the electrode, and further help to improve the stability of the overall performance of the battery 200.

[0088] In some examples, the sleeve 60 of the support tube 20 can be made of polyether ether ketone material.

[0089] In some embodiments, the second output terminal 42 extends along the circumference of the support tube 20 in a ring shape, that is, the second output terminal 42 is located on the second cover plate 12 and surrounds the support tube 20, and this structure helps to increase the heat dissipation area between the second output terminal 42 and the hollow inner cavity 201 of the support tube 20, thereby further improving the heat dissipation effect of the second output terminal 42.

[0090] In other embodiments, the second output terminal 42 is integrally formed with the second cover plate 12, that is, the second output terminal 42 and the second cover plate 12 are one body. The second cover plate 12 is partially protruded away from the mounting chamber 101 and forms the second output terminal 42, and the second output terminal 42 is connected to the support tube 20, that is, the second output terminal 42 is a part of the second cover plate 12, and the second cover plate 12 is connected to the support tube 20 through the second output terminal 42, so as to help the heat generated on the second output terminal 42 to be directly transmitted to the support tube 20 and dissipated through the hollow inner cavity 201 of the support tube 20. In addition, by arranging the second output terminal 42 and the second cover plate 12 as one body, it is also helpful to simplify the overall structure of the battery shell 100, thereby simplifying the assembly process of the battery shell 100 and improving the production efficiency.

[0091] In some embodiments, the first output terminal 41 is electrically connected with the first cover plate 11, and the second output terminal 42 is insulatedly connected with the second cover plate 12, that is, the first output terminal 41 and the second output terminal 42 are respectively arranged on different cover plates, and one is electrically connected with the cover plate and the other is insulatedly connected with the cover plate. Correspondingly, the first cover plate 11 and the second cover plate 12 can be electrically connected or insulated with each other. When the first cover plate 11 and the second cover plate 12 are electrically connected with each other, the first cover plate 11 and the second cover plate 12 can be respectively laser-welded with the edges of the third end 102 and the fourth end 103 of the surrounding plate 10, and at the same time, the first cover plate 11 and the second cover plate 12 are also respectively laser-welded with the edges of the two ends of the support tube 20, that is, the cover plate assembly 13, the surrounding plate 10 and the support tube 20 are directly electrically connected with each other by laser welding. The support tube 20 is used for heat conduction and electrical conduction. This connection mode is simple and convenient, which helps to simplify the assembly of the battery case 100. In addition, the support tube 20 can shorten the overcurrent path of the first output terminal 41 during current transmission, thereby improving the overcurrent capacity of the battery 200. In addition, when the cover plate assembly 13 and the surrounding plate 10 are both conductors, the first output terminal 41 can also transmit current through the surrounding plate 10 and the cover plate assembly 13. At this time, there are two overcurrent paths, which can improve the current collecting capacity of the battery.

[0092] In other embodiments, the first output terminal 41 is electrically connected with the first cover plate 11, and the second output terminal 42 is electrically connected with the second cover plate 12, and the first cover plate 11 and the second cover plate 12 are insulated with each other, that is, the first output terminal 41 and the first cover plate 11 are integrated as one output terminal, and the second output terminal 42 and the second cover plate 12 are integrated as another output terminal. Correspondingly, the first cover plate 11 and the third end 102 of the surrounding plate 10 and one end of the support tube 20 adopt an insulating sealing mode, and the second cover plate 12 and the fourth end 103 of the surrounding plate 10 and the other end of the support tube 20 also adopt an insulating sealing mode. At this time, the support tube 20 is only used for heat conduction and mechanical support, and is not used for electrical conduction. This connection mode makes the overall structure of the first cover plate 11 and the first output terminal 41 and the overall structure of the second cover plate 12 and the second output terminal 42 can be designed to be the same, thereby helping to simplify the cooperation mode between the output terminal assembly 40 and the cover plate assembly 13.

[0093] Since the support tube 20 is arranged to improve the heat dissipation effect of the electrode assembly 301 inside and the output terminal assembly 40, it will occupy a certain space, thereby affecting the energy density of the battery 200 as a whole. Therefore, when designing the support tube 20, its size needs to be considered.

[0094] In some embodiments, the ratio of the diameter of the hollow inner cavity 201 of the support tube 20 to the diameter of the accommodating cavity 111 of the surrounding plate 10 is greater than or equal to 0.05 and less than or equal to 0.1. If the ratio is too small, the support tube 20 cannot effectively dissipate heat. If the ratio is too large, the space occupied by the support tube 20 is too large, which affects the overall energy density of the battery 200.

[0095] In actual production, the ratio of the diameter of the hollow inner cavity 201 of the support tube 20 to the diameter of the accommodating cavity 111 of the surrounding plate 10 can be set to 0.05, 0.06, 0.08, or 0.1, etc. The specific ratio can be selected and adjusted according to actual use requirements, as long as the battery 200 has sufficient overall energy density and the support tube 20 can also have good heat dissipation effect. This is not particularly limited here.

[0096] In some embodiments, when the first output terminal 41 and the second output terminal 42 are located on the same cover plate, for example, the first output terminal 41 and the second output terminal 42 are both mounted on the first cover plate 11, the first output terminal 41 extends along the circumference of the support tube 20 in a ring shape, and the second output terminal 42 is protruded on the first cover plate 11. Since the first output terminal 41 and the second output terminal 42 are respectively used for electrical connection with an external circuit, in order to avoid interference when the first output terminal 41 and the second output terminal 42 are electrically connected with the external circuit, the height of the first output terminal 41 protruding from the first cover plate 11 and the height of the second output terminal 42 protruding from the first cover plate 11 can be set to be equal, so as to facilitate the electrical connection design of the first output terminal 41 and the second output terminal 42 with the external circuit.

[0097] As shown in FIGS. 9 and 11, FIGS. 9 and 11 (a) are respectively a top view of the battery shell, and (b) are respectively a bottom view of the battery shell. The battery shell 100 further comprises a pressure relief valve 140. When the internal pressure of the battery 200 is too large, the pressure relief valve 140 can be opened to discharge the gas inside the battery 200, so as to avoid the safety hazard of explosion caused by the excessive internal pressure of the battery 200. The pressure relief valve 140 can be provided on the first cover plate 11 or the second cover plate 12 in the cover plate assembly 13, or provided on both the first cover plate 11 and the second cover plate 12. The structure of the pressure relief valve 140 can be an annular notch provided on the first cover plate 11 or the second cover plate 12, or a crescent-shaped groove provided on the first cover plate 11 or the second cover plate 12. In addition, the number of pressure relief valves 140 can be one or more. The specific structure shape, setting position, and arrangement number of the pressure relief valve 140 can be selected and adjusted according to actual design requirements, which is not particularly limited here.

[0098] Some embodiments of the present application provide a battery, as shown in FIG. 1, the battery 200 comprises a battery shell 100, the specific structure of the battery shell 100 is referred to the above embodiments, since the battery adopts all the technical solutions of the above embodiments, it at least has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here.

[0099] As shown in FIG. 1, the battery 200 comprises a battery shell 100 and an electrode assembly 301, the electrode assembly 301 is located in the mounting cavity 101 of the battery shell 100 and is sleeved on the support tube 20, the electrode assembly 301 has a first electrode and a second electrode, the first electrode is electrically connected with the first output terminal 41 of the battery shell 100, and the second electrode is electrically connected with the second output terminal 42 of the battery shell 100, the first output terminal 41 and the second output terminal 42 are used to connect with an external circuit, so as to realize the electrical connection between the electrode assembly 301 and the external circuit.

[0100] When the first output terminal 41 and the second output terminal 42 are both mounted on the first cover plate 11 of the cover plate assembly 13, and the first output terminal 41 is electrically connected with the first cover plate 11 and the second output terminal 42 is insulatedly connected with the first cover plate 11, and the first cover plate 11 is electrically connected with the second cover plate 12, the first electrode of the electrode assembly 301 can be electrically connected with the second cover plate 12 through the first current collector 401, so as to realize the electrical connection between the first electrode and the first output terminal 41, and the second electrode of the electrode assembly 301 is separated from the first cover plate 11 and the first output terminal 41 by the lower plastic 500, and realizes the electrical connection with the second output terminal 42 through the second current collector 501 arranged on the side of the lower plastic 500 away from the first cover plate 11.

[0101] It should be noted that the specific connection mode of the first output terminal 41 and the second output terminal 42 with the first electrode and the second electrode of the electrode assembly 301 can be adaptively adjusted according to the specific setting position of the first output terminal 41 and the second output terminal 42, and the electrical connection design mode of the first output terminal 41 and the second output terminal 42 with the corresponding cover plate, which is not specially limited here.

[0102] Specifically, as shown in FIG. 1, the battery shell 100 includes a surrounding plate 10, a support tube 20, a cover plate assembly 13 and an output terminal assembly 40. The surrounding plate 10 has opposite third and fourth ends 102 and 103, and is formed with a receiving cavity 111 extending towards the third and fourth ends 102 and 103. The support tube 20 is located in the receiving cavity 111 and is formed with a hollow inner cavity 201 extending towards the third and fourth ends 102 and 103 and communicating with the outside. The outer surface of the support tube 20 and the inner surface of the surrounding plate 10 jointly form a mounting chamber 101 for mounting an electrode assembly 301. The support tube 20 is used to sleeve the electrode assembly 301. The material of the support tube 20 includes a heat-conducting material. The cover plate assembly 13 connects the surrounding plate 10 and the support tube 20 and seals the mounting chamber 101. The output terminal assembly 40 is arranged on the cover plate assembly 13 and includes first and second output terminals 41 and 42 insulated from each other. At least one of the first and second output terminals 41 and 42 is connected to one end of the support tube 20. By forming the hollow structure of the support tube 20 in the battery shell 100 and communicating with the outside, and connecting at least one output terminal to one end of the support tube 20, the heat generated when the battery shell 100 is applied to the battery 200 can be dissipated to the outside through the hollow inner cavity 201 of the support tube 20, thereby avoiding the concentration of heat on the output terminal and improving the heat dissipation effect of the output terminal.

[0103] In the related art, the roll core generally includes a first separator, a positive electrode sheet, a second separator and a negative electrode sheet arranged in layers. The above-mentioned electrode sheets and separators form the roll core after winding. The center of the roll core is a center hole. The first separator is located on the inner side of the roll core and is prone to wrinkles and other problems, which hinders the insertion of the support tube into the center hole and causes the failure of the installation of the support tube.

[0104] Based on this, in one aspect, some embodiments of the present application also provide a battery. As shown in FIG. 2, the battery 200 includes a roll core 30 and the support tube 20 described in any of the above-mentioned embodiments.

[0105] The battery 100 also includes a shell assembly which can be composed of the surrounding plate 10, the first cover plate 11 and the second cover plate 12. The surrounding plate 10 of the shell assembly is located on the outer side of the support tube 20 and jointly defines a mounting chamber 101 with the support tube 20. The roll core 30 is located in the mounting chamber 101 and arranged around the support tube 20. In this embodiment, the shell assembly, the support tube 20 and the roll core 30 are coaxially arranged.

[0106] The roll core 30 includes a first separator 31 having a hole-burning portion around the axis O of the roll core 30 and having a melting trace. The support tube 20 is in contact with the side wall of the hole-burning portion.

[0107] In some examples, the winding core 30 further comprises a first pole piece 32, a second separator 33 and a second pole piece 34 which are sequentially stacked on one side of the first separator 31.

[0108] As shown in Fig. 12, during the forming process of the winding core 30, the first separator 31, the first pole piece 32, the second separator 33 and the second pole piece 34 are stacked and then wound along the winding direction X. The first separator 31 is wound on the inner side of the winding core 30, while the second pole piece 34 is located on the outer side of the winding core 30. During the winding of the pole pieces and the separators, the winding needle always clamps the first separator 31; after the winding is completed, the winding needle is extracted, so that a central hole is formed in the middle of the winding core 30. During the extraction of the winding needle, the winding needle will extract part of the first separator 31, and the first separator 31 located on the inner side of the winding core 30 has no support and is easy to collapse and form wrinkles, thereby hindering the insertion of the support tube 20 into the central hole.

[0109] Therefore, by providing the first separator 31 with a hole melting part around the central hole, the irregular structure of the first separator 31 can be avoided to hinder the insertion of the support tube 20. The hole melting part can be formed by inserting a hole melting rod with a relatively high temperature (for example, any temperature in the range of 90° to 110°) into the central hole of the winding core 30, so as to form a relatively regular central hole.

[0110] In addition, since the support tube 20 is in contact with the hole melting part of the first separator 31, the hole melting part can be used to conduct the force, so as to avoid the deformation of the first pole piece 32 or the support tube 20 caused by the direct force between the support tube 20 and the first pole piece 32 of the winding core 30.

[0111] In addition, since the support tube 20 is arranged in the middle of the winding core 30, the support tube 20 can provide a certain degree of support for the winding core 30, so as to effectively prevent the collapse of the winding core caused by the expansion of the pole pieces during the charging and discharging of the battery, and also helps to transfer the heat generated during the operation of the winding core 30 to the support tube 20, so as to effectively reduce the temperature inside the winding core 30 and improve the working efficiency.

[0112] On the other hand, some embodiments of the present application provide a mounting method of the battery. As shown in Fig. 13, the mounting method comprises steps S10-S30.

[0113] S10: hole melting is performed on the central hole of the winding core, so that the part of the separator of the winding core around the central hole of the winding core forms a hole melting part with a melting trace.

[0114] For example, a hole-punching rod with a high temperature (for example, any temperature in the range of 90° to 110°) can be inserted into the center hole of the core, so that the part of the diaphragm in contact with the hole-punching rod can form the hole-punched part, and the final core can form a relatively regular center hole.

[0115] S20: placing the hole-punched core into the shell assembly.

[0116] It is worth noting that the shell assembly is composed of the surrounding plate 10, the first cover plate 11 and the second cover plate 12. Before placing the core into the shell assembly, one of the first cover plate 11 and the second cover plate 12 of the shell assembly can not be connected with the surrounding plate 10, so as to reserve an opening for inserting the core, thereby facilitating the placement of the hole-punched core into the shell assembly.

[0117] S30: inserting the support tube 20 into the center hole of the hole-punched core, and making the support tube 20 contact with the side wall of the hole-punched part.

[0118] After hole-punching, the center hole of the core is relatively regular, so that the support tube 20 can be smoothly inserted into the center hole. Since the support tube 20 is in contact with the hole-punched part of the diaphragm, the hole-punched part can be used to conduct force, thereby ensuring the stable contact between the support tube 20 and the core.

[0119] It is worth noting that the order of the step labels in this article does not limit the implementation order of the steps. For example, step S20 can be performed before step S30, or after step S30.

[0120] In some embodiments, as shown in FIG. 14, step S30 includes S301 and S302.

[0121] S301: inserting the support tube 20 into the center hole of the core, and reserving a gap between the support tube 20 and the side wall of the hole-punched part.

[0122] S302: injecting electrolyte into the shell assembly, so that the sleeve 60 of the support tube 20 expands in the electrolyte environment and fills the gap.

[0123] For example, the swelling degree of the sleeve 60 is α, and the initial maximum thickness of the sleeve 60 is D. When the sleeve 60 is in the electrolyte environment, the expansion amount of the sleeve 60 is T, and T = α × D. For example, α = 2, and D = 0.5 mm, so the expansion amount of the sleeve 60 is 1 mm. In this case, a gap of 1 mm is reserved between the core 30 and the support tube 20, so that after the sleeve 60 expands in the electrolyte environment, the expanded sleeve 60 can just contact the side wall of the hole-punched part, thereby being able to form a good support for the core 30.

[0124] At present, when the battery is in a high-temperature, overcharge or short-circuit state, a large amount of gas will be generated in the battery, thereby causing the gas pressure in the battery shell to rise sharply. In order to prevent the battery from exploding, a stress weak part is usually arranged on the battery shell to realize pressure relief and exhaust through the rupture of the stress weak part when the pressure in the battery shell reaches a set pressure.

[0125] In the related art, only the stress weak part is arranged on the battery shell, and if the stress weak part cannot achieve good pressure relief after being broken, the pressure in the battery shell will continue to increase, thereby causing the risk of thermal runaway and violent explosion of the battery.

[0126] Based on this, some embodiments of the present application also provide a battery, as shown in FIG. 2, the battery 200 includes a shell assembly, and a support tube 20 and a winding core 30 arranged in the shell assembly.

[0127] In some embodiments, as shown in FIGS. 2, 5 and 6, the surrounding plate 10 of the shell assembly and the support tube 20 jointly define a mounting chamber 101, and the winding core 30 is located in the mounting chamber 101 and arranged around the support tube 20. For example, the shell assembly, the support tube 20 and the winding core 30 are coaxially arranged.

[0128] The battery 200 also includes a first connecting piece 210 and a second connecting piece 220. The support tube 20 is arranged in a hollow shape, for example, the support tube 20 includes a hollow inner cavity 201, and the support tube 20 has a first end 21 and a second end 22 arranged oppositely, the first end 21 and the shell assembly (for example, the cover plate assembly 13) are connected through the first connecting piece 210, the second end 22 and the shell assembly (for example, the cover plate assembly 13) are connected through the second connecting piece 220, the first connecting piece 210 and the second connecting piece 220 close the mounting chamber 101, and at least one of the first connecting piece 210 and the second connecting piece 220 is a first stress weak part.

[0129] The first stress weak part is configured to open when the mounting chamber 101 is at a first pressure; the shell assembly is provided with a second stress weak part, and the second stress weak part is configured to open when the mounting chamber 101 is at a second pressure, wherein the first pressure is less than the second pressure.

[0130] For the battery 200, the surrounding plate 10 in the shell assembly and the cover plate assembly 13 together with the support tube 20 define a closed installation chamber 101, so that the winding core 30 can be installed in the installation chamber 101. When the battery 200 is in a high-temperature, overcharge, or short-circuit state, a large amount of gas will be generated in the installation chamber 101 and the gas pressure will rise sharply. Since at least one of the first connecting piece 210 and the second connecting piece 220 is the first stress weak part, the gas pressure will cause the first stress weak part to open (i.e. break), thereby realizing the communication between the installation chamber 101 and the outside, and achieving pressure relief and exhaust.

[0131] In addition, since the first stress weak part is arranged at the connecting position between the support tube 20 and the shell assembly, and the connecting position is away from the edge of the shell assembly (for example, the corresponding cover plate in the cover plate assembly 13), the problem that the stress of the first stress weak part changes after the shell assembly is subjected to external impact can be effectively improved, thereby ensuring the opening stability of the first stress weak part. In addition, on the one hand, the support tube 20 can provide a certain degree of support for the winding core 30, thereby effectively preventing the collapse of the winding core due to the expansion of the pole piece during the charging and discharging process of the battery. On the other hand, the support tube 20 is in contact with the winding core 30, and the heat generated during the operation of the winding core 30 can also enter the hollow cavity of the support tube 20, thereby effectively reducing the temperature inside the winding core 30, and further ensuring the stable operation thereof.

[0132] In addition, since the shell assembly is provided with the first stress weak part and the second stress weak part at the same time, and the opening pressure of the second stress weak part is greater than that of the first stress weak part. In this way, when the battery appears thermal runaway, the first stress weak part can be opened first to realize the preliminary pressure relief inside the shell, and the second stress weak part can be opened when the thermal runaway is intensified to realize the further pressure relief inside the shell assembly, so as to effectively reduce the risk of explosion of the battery due to thermal runaway.

[0133] It is worth noting that the first pressure refers to the pressure inside the installation chamber 101 being the first pressure.

[0134] In some examples, the first pressure can be greater than or equal to 0.8 Mpa and less than or equal to 1.2 Mpa. That is, the first stress weak part opens when the installation chamber 101 is in the range of 0.8 Mpa to 1.2 Mpa, thereby realizing the first-stage pressure relief.

[0135] In some examples, the second pressure can be greater than or equal to 1.3 Mpa and less than or equal to 1.9 Mpa. That is, the second stress weak part opens when the installation chamber 101 is in the range of 1.3 Mpa to 1.9 Mpa, thereby realizing the second-stage pressure relief.

[0136] Therefore, when the first stage pressure relief cannot fully meet the pressure release of the installation chamber 101, the second stress weak part is opened when the pressure in the installation chamber 101 continues to increase and reaches the second pressure, thereby effectively meeting the further pressure release requirement of the installation chamber 101.

[0137] It is worth noting that the stress weak part mentioned herein refers to that when the battery 200 is in a high temperature, overcharge or short circuit state, the pressure in the installation chamber 101 increases, and when the pressure increases to a certain extent, the stress weak part can be opened to form an opening, and the opening can communicate the installation chamber 101 with the external environment (i.e. the outside world) where the battery 200 is located, thereby discharging the gas in the installation chamber 101, reducing the risk of battery 200 swelling and even explosion caused by gas production inside the battery 200, and improving the safety of the battery 200.

[0138] In some examples, the stress weak part (the first stress weak part or the second stress weak part) can include at least one of a solid part with a thickness or a strength lower than that of the surrounding area material. Among them, the solid part with a thickness lower than that of the surrounding area material refers to a notch or a groove; the solid part with a strength lower than that of the surrounding area material refers to that the strength of the material of the stress weak part is lower than that of other areas on the shell assembly or the support tube 20, and when there is a certain pressure in the installation chamber 101, the material of the stress weak part is easy to deform and break, thereby forming an opening.

[0139] In some examples, the first stress weak part and the second stress weak part can be arranged in the same way, for example, both of them only include grooves, but the depths of the grooves are different, thereby realizing the opening of the two at different pressures. In some other examples, the first stress weak part and the second stress weak part can also be arranged differently, for example, one of them includes a groove, and the other includes a solid part with a strength lower than that of the surrounding area material.

[0140] In some examples, the first connecting piece 210 is the first stress weak part. In some other examples, the second connecting piece 220 is the first stress weak part. In yet some other examples, the first connecting piece 210 and the second connecting piece 220 are both the first stress weak part.

[0141] For simplicity, some of the following embodiments only describe the case where the first connecting piece 210 is the first stress weak part, and of course, the specific arrangement when the second connecting piece 220 is the first stress weak part can refer to the arrangement when the first connecting piece 210 is the first stress weak part, which will not be described here.

[0142] In some embodiments, as shown in FIG. 5, the housing assembly includes a first weld 1001, and the support tube 20 (e.g., the first end 21) includes a second weld 2101, the first weld 1001 and the second weld 2101 are connected by a first stress weak part, the thickness of the first weld 1001 is greater than the thickness of the second weld 2101. The first weld 1001 is located on the side of the second weld 2101 away from the axis O of the support tube 20, that is, the first weld 1001 is farther away from the axis O of the support tube 20 than the second weld 2101.

[0143] The first stress weak part (e.g., the first connecting piece 210) can be a solder, through which the cover plate assembly in the housing assembly and the support tube 20 are welded and connected.

[0144] When the first connecting piece 210 is the first stress weak part, and the first stress weak part includes a solid part with a strength lower than the material of the surrounding area, the following situations can exist. In the first situation, the material strength of the first connecting piece 210 is lower than the material strength of the housing assembly and the support tube 20, so that under the condition that there is a certain pressure in the installation chamber 101, the first connecting piece 210 can be broken to form an opening and make the gas in the installation chamber 101 exhaust. In the second situation, the material strength of the connection position between the first connecting piece 210 and the housing assembly is lower than the material strength of the surrounding other areas, so that under the condition that there is a certain pressure in the installation chamber 101, the connection position between the first connecting piece 210 and the housing assembly can be broken to form an opening and make the gas in the installation chamber 101 exhaust. In the third situation, the material strength of the connection position between the first connecting piece 210 and the support tube 20 is lower than the material strength of the surrounding other areas, so that under the condition that there is a certain pressure in the installation chamber 101, the connection position between the first connecting piece 210 and the support tube 20 can be broken to form an opening and make the gas in the installation chamber 101 exhaust.

[0145] In some examples, the first connecting piece 210 and the tube body 24 can be integrally formed, and the connection position between the first connecting piece 210 and the housing assembly breaks under the first pressure.

[0146] In other examples, the first connecting piece 210 and the housing assembly can be integrally formed, and the connection position between the first connecting piece 210 and the tube body 24 breaks under the first pressure.

[0147] Since the thickness of the first welding portion 1001 is greater than the thickness of the second welding portion 2101, and the first welding portion 1001 is farther away from the axis O of the support tube 20 than the second welding portion 2101, when the welding point between the first welding portion 1001 and the second welding portion 2101 breaks, the gas in the installation chamber 101 will press the second welding portion 2101 and make it deform towards the axis O of the support tube 20, so that the opening formed after the first stress weak portion is opened is increased, which is more conducive to the pressure relief of the installation chamber 101.

[0148] In some embodiments, the ratio of the thickness of the shell assembly to the thickness of the tube body 24 of the support tube 20 is greater than or equal to 3 and less than or equal to 6. The thickness of the shell assembly can refer to the thickness of one of the first cover plate 11, the second cover plate 12, and the surrounding plate 10. When the thicknesses of the first cover plate 11, the second cover plate 12, and the surrounding plate 10 are all equal, the thickness of the shell assembly is equal to the thickness of the first cover plate 11, the second cover plate 12, and the surrounding plate 10.

[0149] In this way, when the pressure in the installation chamber 101 increases, it is easier to deform the tube body 24, so that the pressure relief of the installation chamber 101 can be achieved by the breakage of the tube body 24. In addition, the thickness of the tube body 24 is relatively small, which on the one hand can improve the area occupied by the tube body 24 and affect the arrangement area of the winding core 30, thereby improving the unit energy density of the battery; on the other hand, it is also conducive to the conduction of heat emitted from the inside of the winding core, thereby enhancing the heat dissipation effect of the winding core.

[0150] In some examples, the thickness of the first welding portion 1001 is the same as the thickness of the shell assembly, and the thickness of the second welding portion 2101 is the same as the thickness of the support tube 20.

[0151] In some embodiments, the first stress weak portion includes a bending segment, and the two ends of the bending segment are integrally connected with the support tube 20 and the shell assembly, respectively. That is, the bending segment, the support tube 20, and the shell assembly are integrally connected. Since the bending segment has a bend, the strength at the bending position is weak, and when the pressure inside the installation chamber 101 is high, the bending segment will be opened and broken, thereby achieving pressure relief inside the shell assembly.

[0152] In some examples, the first connecting member can be solder, and the second connecting member can be a bending segment.

[0153] In some embodiments, as shown in FIGS. 2 and 6, the shell assembly includes a second cover plate 12, and the second connecting member 220 is located between the second end 22 and the second cover plate 12.

[0154] In some embodiments, as shown in FIG. 2 and FIG. 7, the second stress weak part includes a pressure relief valve 140 arranged on the shell assembly, for example, the first notch 120 or a rupture disc. The first notch 120 or the rupture disc can be used to achieve the second stage pressure relief of the installation chamber 101. For example, the second stress weak part can include a first notch arranged on the second cover plate 12, i.e., the first notch 120 is arranged on the second cover plate 12 to achieve the second stage pressure relief of the installation chamber 101.

[0155] In some examples, as shown in FIG. 7, the first notch 120 can be arranged around the axis of the roll core 30, and the axis of the roll core 30 and the axis O of the support tube 20 coincide.

[0156] In some embodiments, a third stress weak part can also be arranged on the shell assembly, and the third stress weak part is configured to open when the installation chamber 101 is at a third pressure, wherein the third pressure is greater than the second pressure.

[0157] In this way, the installation chamber 101 can achieve three-stage pressure relief. That is, when the installation chamber 101 is at the first pressure, the first stress weak part opens to perform the first stage pressure relief; when the pressure in the installation chamber 101 increases to the second pressure, the second stress weak part opens to perform the second stage pressure relief; and when the pressure in the installation chamber 101 continues to increase to the third pressure, the third stress weak part opens to perform the third stage pressure relief.

[0158] In this way, through the multi-level pressure relief design, the installation chamber 101 can be further effectively relieved, thereby effectively improving the problem of violent explosion of the battery caused by battery thermal runaway.

[0159] In some examples, as shown in FIG. 5, the third stress weak part can include a second notch 130 arranged on the second cover plate 12.

[0160] For example, the second notch 130 is arranged around the axis of the roll core 30 and outside the first notch 120. In this way, the second notch 130 can form a larger opening area after breaking, thereby achieving better pressure relief of the installation chamber 101.

[0161] In some embodiments, as shown in FIG. 2, FIG. 5 and FIG. 6, the shell assembly includes a first cover plate 11, a second cover plate 12 and a surrounding plate 10, and the first cover plate 11 and the second cover plate 12 are located at two ends of the surrounding plate 10 and connected with the surrounding plate 10.

[0162] In some examples, the surrounding plate 10 and the second cover plate 12 can be integrally formed. The first cover plate 11 can be fixed on the surrounding plate 10 by welding.

[0163] In some embodiments, the first welding part 1001 is located on the first cover plate 11, the second welding part 2101 is located on the first end 21 of the support tube 20, the first welding part 1001 and the second welding part 2101 are welded through the first connecting piece 210, and the first cover plate 11 can be directly used as the first output terminal 41 of the battery 200.

[0164] Some embodiments of the present application provide a battery pack, which comprises the battery 100 of any of the above embodiments.

[0165] Since the battery pack comprises the battery 100, the battery pack has the technical effects of the battery 100, which will not be described here.

Claims

1. A support tube configured to be embedded in a winding core (30) and support the winding core (30).

2. The support tube of claim 1, wherein, The support tube comprises: a tube body (24); and a tube sleeve (60) covering the tube body (24), the tube sleeve (60) being configured to be embedded in the winding core (30) and contact the winding core (30).

3. The support tube of claim 2, wherein, The tube body (24) is provided in a hollow shape, the tube sleeve (60) is configured to transfer heat at the winding core (30), the tube body (24) is configured to transfer heat at the tube sleeve (60), and at least one end of the tube body (24) is provided with an opening communicating with the outside.

4. The support tube of claim 2, wherein, The tube sleeve (60) comprises a main body portion (61) provided around the tube body (24) and a plurality of protruding portions (62) provided at intervals on a side of the main body portion (61) away from the tube body (24), the protruding portions (62) being configured to contact the winding core (30).

5. The support tube of claim 4, wherein, The side of the protruding portion (62) away from the tube body (24) is provided with a circular arc surface configured to contact the winding core (30).

6. The support tube of claim 4, wherein, The tube sleeve (60) is configured to expand in an electrolyte environment to make the protruding portions (62) contact the winding core (30).

7. The support tube of claim 6, wherein, An initial thickness of the main body portion (61) is t1, an initial thickness of the protruding portion (62) is t2, and 0.5≤t1 / (t1+t2)≤0.

8.

8. The support tube of claim 6, wherein, A swelling degree of the tube sleeve (60) is α, an initial maximum thickness of the tube sleeve (60) is D, and an expansion amount of the tube sleeve (60) in the electrolyte environment is T, where 0 9. The support tube of claim 6, wherein, A material of the tube sleeve (60) is polyether ester, propylene or vinyl, and a material of the tube body (24) is metal.

10. The support tube of claim 2, wherein, The tube body (24) comprises a first end (21) and a second end (22) provided oppositely, and the first end (21) and the second end (22) are configured to connect a cover plate assembly (13) of a battery shell (100) respectively.

11. The support tube of claim 10, wherein, The tube body (24) further comprises an intermediate section (23) between the first end (21) and the second end (22), and an outer diameter of the first end (21) and the second end (22) is smaller than an outer diameter of the intermediate section (23). 12.A battery shell comprising: a surrounding plate (10) having a third end (102) and a fourth end (103) provided oppositely, the surrounding plate (10) being formed with an accommodating cavity (111), and an extension direction of the accommodating cavity (111) being towards the third end (102) and the fourth end (103); and The support tube (20) according to any one of claims 1-11, wherein the support tube (20) is located in the accommodating cavity (111), the support tube (20) is provided with a hollow inner cavity (201), the hollow inner cavity (201) extends towards the third end (102) and the fourth end (103), and the hollow inner cavity (201) is in communication with the outside; an outer surface of the support tube (20) and an inner surface of the surrounding plate (10) jointly form a mounting chamber (101) configured to mount an electrode assembly (301), and the support tube (20) is configured to cover the electrode assembly (301); and the support tube (20) is made of a heat-conducting material. The battery shell (100) further comprises a cover plate assembly (13) and an output terminal assembly (40), the cover plate assembly (13) connects the surrounding plate (10) and the support tube (20), and the cover plate assembly (13) seals the mounting chamber (101); the output terminal assembly (40) is mounted on the cover plate assembly (13), and the output terminal assembly (40) comprises a first output terminal (41) and a second output terminal (42) which are insulated from each other, and at least one of the first output terminal (41) and the second output terminal (42) is connected to one end of the support tube (20).

13. The battery case of claim 12, wherein, The first output terminal (41) extends in a ring shape along the circumference of the support tube (20).

14. The battery case of claim 12, wherein, The cover plate assembly (13) comprises a first cover plate (11) and a second cover plate (12), the first cover plate (11) connects the third end (102) of the surrounding plate (10) and the support tube (20), and the second cover plate (12) connects the fourth end (103) of the surrounding plate (10) and the support tube (20); the first output terminal (41) is mounted on the first cover plate (11), and the first output terminal (41) is connected to one end of the support tube (20); wherein, The second output terminal (42) is mounted on the first cover plate (11); or, the second output terminal (42) is mounted on the second cover plate (12).

15. The battery case of claim 14, wherein, The first output terminal (41) is integrally formed with the first cover plate (11); the first cover plate (11) is partially protruded away from the mounting chamber (101) and forms the first output terminal (41).

16. The battery case of claim 14, wherein, The second output terminal (42) is mounted on the second cover plate (12), and the second output terminal (42) is connected to the other end of the support tube (20); the support tube (20) is made of an insulating heat-conducting material.

17. The battery case of claim 16, wherein, The second output terminal (42) extends in a ring shape along the circumference of the support tube (20).

18. The battery case of claim 16, wherein, The second output terminal (42) is integrally formed with the second cover plate (12); the second cover plate (12) is partially protruded away from the mounting chamber (101) and forms the second output terminal (42).

19. The battery case of claim 16, wherein, The first output terminal (41) is electrically connected with the first cover plate (11), and the second output terminal (42) is insulatedly connected with the second cover plate (12); or The first output terminal (41) is electrically connected with the first cover plate (11), and the second output terminal (42) is electrically connected with the second cover plate (12), and the first cover plate (11) and the second cover plate (12) are insulated from each other.

20. The battery case of any one of claims 12-19, wherein, The ratio of the diameter of the hollow inner cavity (201) to the diameter of the accommodating cavity (111) is greater than or equal to 0.05 and less than or equal to 0.

1.

21. A battery comprising: The battery shell (100) according to any one of claims 12 to 19; And An electrode assembly (301) is located in the mounting chamber (101) of the battery shell (100) and is sleeved on the support tube (20); the electrode assembly (301) has a first electrode and a second electrode, the first electrode is electrically connected with the first output terminal (41) of the battery shell (100), and the second electrode is electrically connected with the second output terminal (42) of the battery shell (100).

22. A battery comprising: The winding core (30) and the support tube (20) according to any one of claims 1 to 11, the winding core (30) is arranged around the support tube (20).

23. The battery of claim 22, wherein, The battery further comprises a shell assembly located outside the support tube (20) and cooperatively defining a mounting chamber (101) with the support tube (20), and the winding core (30) is located in the mounting chamber (101); the winding core (30) comprises a first separator (31) having a heat-sealed hole portion around an axis of the winding core (30) and having a melting trace, and the support tube (20) is in contact with a side wall of the heat-sealed hole portion.

24. The battery of claim 22, wherein, The battery further comprises a shell assembly, a first connecting member (210) and a second connecting member (220), the shell assembly is located outside the support tube (20) and cooperatively defines a mounting chamber (101) with the support tube (20), and the winding core (30) is located in the mounting chamber (101); the support tube (20) is arranged in a hollow shape and comprises a first end (21) and a second end (22) arranged oppositely; the first connecting member (210) is connected with the first end (21) and the shell assembly, and the second connecting member (220) is connected with the second end (22) and the shell assembly; the first connecting member (210) and the second connecting member (220) enclose the mounting chamber (101), and at least one of the first connecting member (210) and the second connecting member (220) is a first stress weak portion configured to be opened when the mounting chamber (101) is under a first pressure; the shell assembly is provided with a second stress weak portion configured to be opened when the mounting chamber (101) is under a second pressure, and the first pressure is less than the second pressure.

25. The battery of claim 24, wherein, The shell assembly includes a first welding portion (1001), and the support tube (20) includes a second welding portion (2101); the first welding portion (1001) and the second welding portion (2101) are welded through the first stress-weak portion.

26. The battery of claim 25, wherein, The first welding portion (1001) has a thickness greater than that of the second welding portion (2101), and the first welding portion (1001) is located on a side of the second welding portion (2101) away from an axis of the support tube (20).

27. The battery of claim 24, wherein, The first stress-weak portion includes a bending section, and two ends of the bending section are integrally connected with the support tube (20) and the shell assembly, respectively.

28. The battery of claim 24, wherein, The ratio of the thickness of the shell assembly to the thickness of the tube body (24) of the support tube (20) is greater than or equal to 3 and less than or equal to 6.

29. The battery of claim 24, wherein, The second stress-weak portion includes a pressure relief valve (140) arranged on the shell assembly.

30. A battery pack comprising: The battery of any one of claims 21-29.

31. A method of installing a battery, comprising: punching a center hole of a jelly-roll (30) to form a punched portion with a melting trace in a part of a separator of the jelly-roll (30) around the center hole of the jelly-roll (30); placing the jelly-roll (30) in a shell assembly; and inserting a support tube (20) into the center hole of the jelly-roll (30) and making the support tube (20) contact a side wall of the punched portion.

32. The method of installing a battery of claim 31, wherein, The inserting the support tube (20) into the center hole of the jelly-roll (30) and making the support tube (20) contact the side wall of the punched portion includes: inserting the support tube (20) into the center hole of the jelly-roll (30) and making a gap between the support tube (20) and the side wall of the punched portion; and injecting an electrolyte into the shell assembly to make a tube sleeve (60) of the support tube (20) swell and fill the gap in the electrolyte environment.

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