Ring-shaped battery, battery module, and electric device

Abstract

A ring-shaped battery, a battery module, and an electric device. The ring-shaped battery comprises a battery case, wherein the battery case comprises an outer peripheral wall and an inner peripheral wall which runs through the inside of the outer peripheral wall, one end of the inner peripheral wall being sealed. The present solution at least improves the heat dissipation performance of the battery.

Description

Ring batteries, battery modules and electrical equipment

[0001] This application is based on Chinese patent applications with application number 202322307005.6 and application date on August 25, 2023, and application number 202322493104.8 and application date on September 13, 2023, and claims the priority of these two Chinese patent applications. The entire contents of the two Chinese patent applications are hereby introduced into this application as a reference. Technical Field

[0002] The utility model belongs to the technical field of lithium batteries, and specifically relates to a ring-shaped battery, a battery module and electrical equipment. Background Art

[0003] Lithium-ion batteries have the advantages of light weight, high energy density, long cycle life and high safety performance, and have become the mainstream battery.

[0004] The main forms of lithium-ion batteries are prismatic, cylindrical, and pouch cells. Cylindrical batteries offer a high degree of automation, high production efficiency, good consistency, and relatively low cost.

[0005] At present, cylindrical batteries basically adopt a fully closed structure. As the energy density and power density of lithium-ion batteries become higher and higher, the charge and discharge rates are also getting larger and larger, and the heat generation rate of the battery is also increasing accordingly. However, due to the poor radial thermal conductivity of cylindrical batteries, the battery size is limited, and the battery electrical performance and safety performance are reduced.

[0006] Utility Model Content

[0007] In view of the above-mentioned defects or deficiencies in the prior art, it is desired to provide a ring-shaped battery, a battery module, and an electrical device, at least for improving the heat dissipation performance of the battery.

[0008] In a first aspect, the present invention provides a ring-shaped battery, comprising: a battery housing, wherein the battery housing comprises an outer peripheral wall and an inner peripheral wall penetrating the outer peripheral wall, wherein one end of the inner peripheral wall is closed.

[0009] As an implementation manner, a first hole is provided on the inner peripheral wall, the first hole extends along the axis of the inner peripheral wall and is closed at one end.

[0010] As an implementation manner, a first end cover is provided at one end of the outer peripheral wall, one end of the inner peripheral wall is connected to the first end cover, and the first hole is closed at one end close to the first end cover.

[0011] As an achievable manner, the first hole is a through hole provided in the inner circumferential wall, and the first end cover closes one end of the first hole; or, the first hole is a blind hole provided in the inner circumferential wall, and the inner circumferential wall is connected to the first end cover at the end closed by the first hole.

[0012] As an implementation method, a first end cover is provided at one end of the outer peripheral wall, the first end cover is provided with a second hole, the second hole is a through hole, one end of the inner peripheral wall is connected to the first end cover, the first hole is connected to the second hole, and the first hole is closed at the end away from the first end cover.

[0013] As an achievable embodiment, the first hole is a through hole provided in the inner circumferential wall, and a second end cover provided at the other end of the outer circumferential wall closes one end of the first hole; or, the first hole is a blind hole provided in the inner circumferential wall, and the inner circumferential wall is connected to the first end cover at the end open to the first hole.

[0014] As an implementation method, the annular battery further includes an annular battery core, one of the first end cover and the second end cover is provided with a positive electrode column and a negative electrode column, the positive electrode ear of the annular battery core is electrically connected to the positive electrode column, and the negative electrode ear of the annular battery core is electrically connected to the negative electrode column; or,

[0015] One of the first end cover and the second end cover is provided with a positive pole, and the other is provided with a negative pole; the positive pole ear at one end of the annular battery core is electrically connected to the positive pole, and the negative pole ear at the other end of the annular battery core is electrically connected to the negative pole.

[0016] As an implementation method, the outer peripheral wall and the first end cover are an integral structure, or the outer peripheral wall and the first end cover are fixed by welding.

[0017] As an implementation method, the inner circumferential wall and the first end cover are an integral structure, or the inner circumferential wall and the first end cover are fixed by welding.

[0018] As an implementable manner, the maximum straight-line distance between any two points on the cross section of the first hole is 0.11-0.65 of the maximum straight-line distance between any two points on the cross section of the outer peripheral wall.

[0019] As an implementable manner, the maximum straight-line distance between any two points on the cross section of the first hole is 5 mm to 30 mm.

[0020] As an implementable manner, the maximum straight-line distance between any two points on the cross section of the first hole is 8 mm to 25 mm.

[0021] As an implementable manner, the maximum straight-line distance between any two points on the cross section of the first hole is 10 mm to 15 mm.

[0022] As an implementable manner, a plurality of heat dissipation protrusions are provided on the hole wall of the first hole.

[0023] As an implementable manner, each of the heat dissipation protrusions is an annular protrusion arranged around the hole wall, or a point-shaped protrusion or a columnar protrusion uniformly distributed on the hole wall.

[0024] As an implementation method, the annular battery further includes an annular battery core, which is sleeved on the outside of the inner circumferential wall, and an insulating member is provided between the outer side surface of the inner circumferential wall and the inner side surface of the annular battery core.

[0025] As an implementation method, the insulating member includes a layered structure covering the outer side surface of the inner peripheral wall; or,

[0026] The insulating member includes an annular structure provided at at least one end of the inner peripheral wall.

[0027] As an implementation manner, the cross section of the outer peripheral wall and / or the inner peripheral wall is a circle, a regular polygon, an ellipse or a non-equilateral polygon.

[0028] As an implementation manner, the cross section of the first hole is a circle, a regular polygon, an ellipse or a non-equilateral polygon.

[0029] As an implementation manner, the cross section of the toroidal core is a circle, a regular polygon, an ellipse or a non-equilateral polygon.

[0030] In a second aspect, the present invention provides a battery module comprising a plurality of annular batteries as described above, wherein the plurality of annular batteries are connected in series and / or in parallel.

[0031] In a third aspect, the present invention provides an electrical device comprising a plurality of annular batteries as described above; or comprising the battery module described above.

[0032] The above solution, by closing one end of the inner circumferential wall, is simple to process and allows the inner circumferential wall to have a larger specific surface area, thereby improving the heat dissipation performance without the need for additional heat dissipation design. The cooling medium dissipates heat from the middle portion of the annular battery through the first hole in the inner circumferential wall, thereby improving the heat dissipation performance compared to heat dissipation from only the outer circumferential surface of the battery. Based on the improved heat dissipation performance, the battery size can be further increased. In addition, the temperature of the annular battery of this solution will not reach high temperature due to poor heat dissipation, so that the annular battery of this solution can operate in a more ideal temperature environment. The activity of the active material in the annular battery is high, thereby improving the electrical performance of the annular battery. In addition, since the annular battery does not have the problem of high temperature, the problem of battery combustion or even explosion due to high temperature is avoided, thereby improving the safety performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Other features, objects and advantages of the present application will become more apparent upon reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0034] FIG1 is a perspective view of a ring-shaped battery provided in an embodiment of the present invention;

[0035] FIG2 is a top view of FIG1 ;

[0036] FIG3 is a cross-sectional view of the AA portion of FIG2;

[0037] FIG4 is a cross-sectional view corresponding to the portion taken along the line 2A-A of FIG2A;

[0038] FIG5 is a cross-sectional view corresponding to the portion taken along the line 2A-A of FIG2A;

[0039] FIG6 is a cross-sectional view corresponding to the portion taken along the line 2A-A of FIG2A;

[0040] FIG7 is a cross-sectional view corresponding to the portion taken along the line 2A-A of FIG2A;

[0041] FIG8 is a perspective view of a ring-shaped battery provided in another embodiment of the present invention (end caps not shown);

[0042] FIG9 is a perspective view of a ring-shaped battery provided in another embodiment of the present invention;

[0043] FIG10 is an exploded view of a ring-shaped battery provided in another embodiment of the present invention;

[0044] FIG11 is a schematic structural diagram of a toroidal battery provided by another embodiment of the present invention, wherein the positive and negative tabs of the toroidal battery core are not flattened;

[0045] FIG12 is a schematic diagram of the structure corresponding to FIG11 after the positive electrode tab and the negative electrode tab are flattened;

[0046] FIG13 is a top view of a toroidal battery cell provided in another embodiment of the present invention;

[0047] FIG14 is a cross-sectional view of the BB portion of FIG13;

[0048] FIG15 is a cross-sectional view of the CC portion of FIG13;

[0049] FIG16 is a schematic structural diagram of a second end cover provided in another embodiment of the present invention.

[0050] Explanation of the accompanying drawings: battery case 1, first end cover 11, second hole 111, injection hole 113, explosion-proof valve 114, hole 115, inner wall 12, first hole 121, heat dissipation protrusion 122, outer wall 13, second end cover 14, positive electrode column 141, negative electrode column 142; ring-shaped battery cell 2, positive electrode ear 21, negative electrode ear 22, center hole 23; insulation layer 3; ring structure 4. DETAILED DESCRIPTION

[0051] The present application will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the relevant utility model and are not intended to limit the utility model. It should also be noted that, for ease of description, only the portions relevant to the utility model are shown in the accompanying drawings.

[0052] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0053] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The singular forms "a," "the," and "the" used in this application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and encompasses any or all possible combinations of one or more of the associated listed items.

[0054] As shown in Figures 1 to 3, the annular battery provided by the embodiment of the present invention includes: a battery shell 1, the battery shell 1 includes an outer peripheral wall 13 and an inner peripheral wall 12 passing through the outer peripheral wall 13, and one end of the inner peripheral wall 12 is closed. A first hole 121 is provided on the inner peripheral wall 12, and the first hole 121 extends along the axis of the inner peripheral wall 12 and is closed at one end. By providing the first hole on the inner peripheral wall and closing one end of the first hole, on the one hand, the processing is simple, and on the other hand, the closure of one end of the first hole makes the first hole have a larger specific surface area, thereby improving the heat dissipation performance without the need for additional heat dissipation design. The cooling medium passes through the first hole to dissipate heat to the middle part of the annular battery, thereby improving the heat dissipation performance compared to heat dissipation relying solely on the outer peripheral surface of the battery.

[0055] The material of the battery housing 1 is, for example but not limited to, steel, aluminum alloy, etc.

[0056] The battery case 1 includes an outer peripheral wall 13 and an inner peripheral wall 12 extending within the outer peripheral wall 13. A cavity for accommodating a battery cell is formed between the outer side of the inner peripheral wall 12 and the inner side of the outer peripheral wall 13. The battery cell is encapsulated within the cavity. The battery case 1 is used to protect the encapsulated battery cell.

[0057] One end of the first hole 121 can be closed by the following structure. For example, if the first hole 121 itself is a blind hole, one end thereof is naturally closed. If the first hole 121 itself is a through hole, one end thereof can be closed by other components, such as by using the following end cap to close one end thereof.

[0058] Specifically, as shown in Figure 3, a first end cover 11 is provided at one end of the outer peripheral wall 13, one end of the inner peripheral wall 12 is connected to the first end cover 11, and the first hole 121 is closed at one end close to the first end cover 11. In this example, the first hole 121 is a through hole provided in the inner peripheral wall 12, and one end of the first through hole 121 is closed by the first end cover 11.

[0059] In other examples, as shown in FIG. 4 , the first hole 121 is a blind hole provided in the inner peripheral wall 12 , and the inner peripheral wall 12 is connected to the first end cover 11 at one end where the first hole 121 is closed.

[0060] In other examples, as shown in FIG5 , a first end cap 11 may be provided at one end of the outer circumferential wall 13, the first end cap 11 being provided with a second hole 111, the second hole 111 being a through hole, one end of the inner circumferential wall 12 being connected to the first end cap 11, the first hole 121 being in communication with the second hole 111, and the first hole 121 being closed at the end away from the first end cap 11. In this example, one end of the first hole 121 is closed by the second end cap 14. Of course, in other examples, the first through hole 111 may also be a blind hole. In this case, the inner circumferential wall 12 is connected to the first end cap 11 at the end open to the first hole 121, and is connected to the second end cap 14 at the end closed to the first hole 121.

[0061] In order to adapt to the structure of the above-mentioned battery shell 1, the battery cell encapsulated in the above-mentioned cavity is a ring-shaped battery cell 2, which can be prepared by winding. For example, the positive electrode film roll coated with the positive electrode material, the negative electrode film roll coated with the negative electrode material, and the diaphragm roll are respectively provided to the battery cell winding equipment, and the battery cell winding equipment stacks the positive electrode film drawn from the positive electrode film roll, the negative electrode film drawn from the negative electrode film roll, and the diaphragm drawn from the diaphragm roll together, and the diaphragm is located between the positive electrode film and the negative electrode film, and the three are wound to form a ring-shaped battery cell 2 with a central hole 23 in the middle (see at least Figures 9 to 11). After the ring-shaped battery cell 2 is encapsulated in the above-mentioned cavity, the inner peripheral wall 12 passes through the central hole 23.

[0062] In addition, in order to ensure that the inner circumferential wall 12 and the annular battery core 2 are in a good insulation state, an insulating member can be provided between the outer side surface of the inner circumferential wall 12 and the inner side surface of the annular battery core 2 to isolate the inner circumferential wall 12 from the annular battery core 2, and avoid electrical connection between the two, which may cause problems such as leakage and short circuit of the annular battery; specifically, it is mainly used to prevent the pole ears from contacting the inner circumferential wall 12 and causing a short circuit.

[0063] Among them, at least referring to Figure 3, the insulating part may include a layered structure 3 coated on the outer side of the inner circumferential wall 12; in other examples, at least referring to Figure 8, the insulating part may also include an annular structure 4, which is arranged at at least one end of the inner circumferential wall 12.

[0064] For example, in the structure with tabs at both ends shown in FIG8 , that is, the positive and negative tabs are respectively placed at the two ends of the annular battery, the annular structure 4 can be provided at both ends of the inner peripheral wall 12 .

[0065] Of course, in other examples, in a structure with a tab at one end, that is, the positive and negative tabs are placed at one end of the annular battery, the annular structure 4 can also be provided at only one end of the inner circumferential wall 12, and the annular structure 4 is located at the end of the inner circumferential wall 12 close to the tab.

[0066] The annular battery of the present application may have an outer shape of a cylinder, a regular polygonal column, an elliptical column, a non-equilateral polygonal column, etc. Among them, the outer shape of the annular battery shown in Figure 1 is a cylinder, and the outer shape of the annular battery shown in Figure 5 is a regular polygonal column, and it is a regular hexagonal column. Of course, in other examples, it can also be a regular polygonal column with other numbers of sides, such as a regular pentagonal column, a regular octagonal column, etc. Specifically, the cross-section of the outer peripheral wall 13 may be a circle, a regular polygon, an elliptical or a non-equilateral polygon. Correspondingly, the cross-section of the inner peripheral wall 12 may also be a circle, a regular polygon, an elliptical or a non-equilateral polygon. The cross-section of the first hole 121 may also be a circle, a regular polygon, an elliptical or a non-equilateral polygon. The cross-section of the annular battery core 2 may also be a circle, a regular polygon, an elliptical or a non-equilateral polygon.

[0067] The cross section described herein is a cross section perpendicular to the axis of the inner peripheral wall 12 .

[0068] In the above embodiment, by providing the first hole 121 in the inner peripheral wall 12, a cooling medium can pass through the first hole 121 to dissipate heat from the central portion of the annular battery. This improves heat dissipation performance compared to heat dissipation solely from the outer peripheral surface of the battery. With this improved heat dissipation performance, the battery size can be further increased. Furthermore, the annular battery of this embodiment does not reach high temperatures due to poor heat dissipation, allowing the annular battery of this embodiment to operate in a relatively ideal temperature environment. The active material within the annular battery is highly active, thereby improving the electrical performance of the annular battery. Furthermore, since the annular battery does not experience high temperatures, combustion or even explosion of the battery due to high temperatures is avoided, thereby improving safety performance.

[0069] As a possible implementation method, referring to at least FIG5 or FIG6 or FIG7, the outer peripheral wall 13 and the first end cover 11 are an integral structure. For example, a metal plate can be stamped to form the outer peripheral wall 13 and the first end cover 11 connected as one piece. Of course, the outer peripheral wall 13 and the first end cover 11 can also be formed as one piece by casting.

[0070] In other implementations, referring at least to FIG. 3 or FIG. 4 , the outer peripheral wall 13 and the first end cover 11 may also be two independent components that are fixedly connected together by welding.

[0071] In other implementations, as shown in FIG7 , the inner circumferential wall 12 and the first end cap 11 are integrally formed. For example, a metal plate can be stamped to form the integrally connected inner circumferential wall 12 and the first end cap 11. Alternatively, the integrally connected inner circumferential wall 12 and the first end cap 11 can be formed by casting. In this case, the outer circumferential wall 13, the inner circumferential wall 12, and the first end cap 11 can be integrally formed.

[0072] In other implementations, referring at least to FIG. 3 or FIG. 4 , the inner peripheral wall 12 and the first end cover 11 may also be two independent components that are fixedly connected together by welding.

[0073] As an achievable approach, the maximum straight-line distance between any two points on the cross-section of the first hole 121 is 0.11-0.65 of the maximum straight-line distance between any two points on the cross-section of the outer peripheral wall 13. The above relationship between the maximum straight-line distance between any two points on the cross-section of the first hole 121 and the maximum straight-line distance between any two points on the cross-section of the outer peripheral wall 13 can achieve a balance between battery capacity and heat dissipation. Specifically, while ensuring that the annular battery has a large capacity, it also meets the need for heat dissipation in the central portion.

[0074] Among them, the maximum straight-line distance between any two points on the cross section can be understood as follows: when the cross section is a circle, the maximum straight-line distance between any two points on the cross section can refer to the diameter of the circle; when the cross section is an ellipse, the maximum straight-line distance between any two points on the cross section can refer to the major axis of the ellipse; when the cross section is a polygon, the maximum straight-line distance between any two points on the cross section can refer to the maximum distance between any two vertices of the polygon.

[0075] For example, in the example of Figure 1, the cross-section of the outer peripheral wall 13 is circular, and the first hole 121 of the inner peripheral wall 12 is a circular hole. The maximum straight-line distance between any two points on the cross-section of the first hole 121 is 0.11-0.65 of the maximum straight-line distance between any two points on the cross-section of the outer peripheral wall 13 of the battery housing 1, that is, the diameter of the first hole 121 is 0.11-0.65 of the outer diameter of the outer peripheral wall 13.

[0076] As an implementable manner, the maximum straight-line distance between any two points on the cross section of the first hole 121 is 5 mm to 30 mm.

[0077] As an implementable manner, the maximum straight-line distance between any two points on the cross section of the first hole 121 is 8 mm to 25 mm.

[0078] As an implementable manner, the maximum straight-line distance between any two points on the cross section of the first hole 121 is 10 mm to 15 mm.

[0079] For example, but not limited to, the maximum straight-line distance between any two points on the cross section of the first hole 121 is 5.15 mm, 5.3 mm, 6.25 mm, 7 mm, 8.66 mm, 13 mm, 15.35 mm, 18.7 mm, 19 mm, 22.9 mm, 24 mm, 28.4 mm, 29.46 mm, etc. The maximum straight-line distance between any two points on the cross section of the first hole 121 can be determined according to actual needs, as long as the maximum straight-line distance between any two points on the cross section of the first hole 121 is 0.11-0.65 of the maximum straight-line distance between any two points on the cross section of the outer peripheral wall 13 of the battery casing 1. In addition, generally, the longer the length of the annular battery, the larger the maximum value of the straight-line distance between any two points on the cross section of the first hole 121 can be, that is, the maximum value of the straight-line distance between any two points on the cross section of the first hole 121 is positively correlated with the length of the annular battery, so that the cooling medium can fully exchange heat in the first hole 121, so as to take away the heat from the center of the annular battery as much as possible, thereby improving the heat dissipation effect of the annular battery.

[0080] The cooling medium may be gas or liquid. Preferably, liquid is used to dissipate heat from the annular battery to improve heat dissipation performance.

[0081] As an achievable approach, referring at least to FIG3 , to enhance the heat dissipation capability of the annular battery, a plurality of heat dissipation protrusions 122 are provided on the wall of the first hole 121. By providing a plurality of heat dissipation protrusions 122 on the wall of the first hole 121, the surface area of ​​the wall of the first hole 121 is increased. As the surface area increases, the area in contact with the cooling medium also increases, and the area for heat exchange increases accordingly. Heat in the center of the annular battery can be fully exchanged with the cooling medium flowing through the first hole 121, removing heat from the center of the annular battery and reducing the temperature of the annular battery during charging and discharging.

[0082] As an implementation, each heat dissipation protrusion 122 is an annular protrusion disposed around the hole wall. Dissipation protrusions 122 are provided as an annular protrusion surrounding the hole wall, which can evenly dissipate heat around the hole wall. It is understood that heat dissipation protrusions 122 can also be dot-shaped, columnar, or other shaped protrusions, and are not limited to the annular protrusions described in the above implementation.

[0083] As an implementation method, the two ends of the outer peripheral wall 13 are respectively provided with a first end cover 11 and a second end cover 14;

[0084] Generally, the first end cap 11 and the second end cap 14 can be sealed and connected to the outer peripheral wall 13 by welding to prevent leakage of the electrolyte. Of course, in other examples, other connection methods such as riveting and crimping can also be used to fix the first end cap 11 and the second end cap 14 to the ends of the outer peripheral wall 13. In addition, as mentioned above, the first end cap 11 can also be an integral structure with the outer peripheral wall 13.

[0085] As shown in at least FIG. 16 , both the first end cover 11 and the second end cover 14 are provided with a hole 115 exposing the first hole 121 .

[0086] In one implementation, referring at least to Figures 3 and 11-15, the annular battery can have tabs on the same side, that is, a positive electrode column 141 and a negative electrode column 142 are provided on the second end cover 14, and an annular battery cell 2 is encapsulated in the battery shell 1, and a positive tab 21 and a negative tab 22 are provided at the same end of the annular battery cell 2, the positive tab 21 is electrically connected to the positive electrode column 141, and the negative tab 22 is electrically connected to the negative electrode column 142.

[0087] Generally, after the annular battery core 2 is wound and formed, its positive electrode ear 21 and negative electrode ear 22 are still in a sheet structure. In order to electrically connect the positive electrode ear 21 and negative electrode ear 22 with their corresponding positive electrode column 141 and negative electrode column 142, before or after the annular battery core 2 is installed in the battery shell 1, pressure can be applied to the positive electrode ear 21 and negative electrode ear 22 axially along the inner circumferential wall 12 to deform the positive electrode ear 21 and negative electrode ear 22 (this process can be called flattening) so that the positive electrode ear 21 and negative electrode ear 22 form a flat surface in surface contact with the corresponding positive electrode column 141 and negative electrode column 142. Through surface contact, the welding strength between the positive electrode ear 21 and the positive electrode column 141, as well as the welding strength between the negative electrode ear 22 and the negative electrode column 142 can be improved, and the connection resistance between the positive electrode ear 21 and the positive electrode column 141, as well as the connection resistance between the negative electrode ear 22 and the negative electrode column 142 can be reduced.

[0088] The welding referred to herein may be, but is not limited to, laser welding, ultrasonic welding, resistance welding, electromagnetic welding, friction welding, electric resistance welding, and the like.

[0089] In another implementation, at least referring to Figure 10, the annular battery can have pole ears on both sides, that is, a positive pole column 141 is provided on the first end cover 11, and a negative pole column 142 is provided on the second end cover 14. In this example, two positive pole columns 141 and two negative pole columns 142 are provided; an annular battery cell 2 is encapsulated in the battery shell 1, and a positive pole ear 21 is provided at one end of the annular battery cell 2, and a negative pole ear 22 is provided at the other end. The positive pole ear 21 is electrically connected to the positive pole column 141, and the negative pole ear 22 is electrically connected to the negative pole column 142.

[0090] In some examples, as also shown in at least FIG16 , an explosion-proof valve 114 and a liquid injection hole 113 can be provided on the second end cap 14 , and electrolyte can be injected into the annular battery through the liquid injection hole 113 . During the formation process after the electrolyte is injected, the liquid injection hole 113 can serve as a vent for discharging gas generated by the formation from the battery housing 1 . After the formation is completed, the liquid injection hole 113 can be sealed, for example, but not limited to, by welding a sealing nail into the liquid injection hole 113 .

[0091] For annular batteries with positive and negative electrodes located at both ends of the battery, the structures of the first end caps 11 and second end caps 14 provided at both ends may be the same or different. For example, but not limited to, the second end cap 14 on the positive electrode side may be provided with an explosion-proof valve 114 and a liquid injection hole 113, while the first end cap 11 on the negative electrode side may be provided with a liquid injection hole 113 but not an explosion-proof valve 114.

[0092] In a second aspect, the present invention provides a battery module comprising a plurality of annular batteries as described above, wherein the plurality of annular batteries are connected in series and / or in parallel.

[0093] The number of ring batteries used and their series-parallel relationship can be determined based on the output voltage and capacity of the battery module.

[0094] In a third aspect, the present invention provides an electrical device comprising a plurality of annular batteries as described above; or comprising the battery module described above.

[0095] Electrical equipment includes, but is not limited to, new energy vehicles (electric vehicles, hybrid vehicles, etc.), digital products, etc.

[0096] It should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like used above to indicate orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0097] The above description is merely a preferred embodiment of the present application and an illustration of the technical principles employed. Those skilled in the art should understand that the scope of the utility model disclosed in this application is not limited to the technical solutions formed by the specific combination of the above-mentioned technical features, but also encompasses other technical solutions formed by any combination of the above-mentioned technical features or their equivalents without departing from the inventive concept. For example, a technical solution formed by replacing the above-mentioned features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A ring-shaped battery, characterized in that: include: A battery casing (1), the battery casing (1) comprising an outer peripheral wall (13) and an inner peripheral wall (12) penetrating the outer peripheral wall (13), one end of the inner peripheral wall (12) being closed.

2. The annular battery according to claim 1, characterized in that: The inner peripheral wall (12) is provided with a first hole (121), the first hole (121) extends along the axis of the inner peripheral wall (12), and one end of the first hole (121) is closed.

3. The annular battery according to claim 2, characterized in that: A first end cover (11) is provided at one end of the outer peripheral wall (13), one end of the inner peripheral wall (12) is connected to the first end cover (11), and the first hole (121) is closed at one end close to the first end cover (11).

4. The annular battery according to claim 3, characterized in that: The first hole (121) is a through hole arranged in the inner circumferential wall (12), and the first end cover (11) closes one end of the first hole (121); or, the first hole (121) is a blind hole arranged in the inner circumferential wall (12), and the inner circumferential wall (12) is connected to the first end cover (11) at the end closed by the first hole (121).

5. The annular battery according to claim 2, characterized in that: A first end cover (11) is provided at one end of the outer peripheral wall (13), and the first end cover (11) is provided with a second hole (111), and the second hole (111) is a through hole. One end of the inner peripheral wall (12) is connected to the first end cover (11), and the first hole (121) is communicated with the second hole (111), and the first hole (121) is closed at an end away from the first end cover (11).

6. The annular battery according to claim 5, characterized in that: The first hole (121) is a through hole arranged in the inner peripheral wall (12), and a second end cover (14) arranged at the other end of the outer peripheral wall (13) closes one end of the first hole (121); or, the first hole (121) is a blind hole arranged in the inner peripheral wall (12), and the inner peripheral wall (12) is connected to the first end cover (11) at the end open to the first hole (121).

7. The annular battery according to claim 6, characterized in that: The annular battery further comprises an annular battery cell (2), one of the first end cover (11) and the second end cover (14) being provided with a positive electrode column (141) and a negative electrode column (142), the positive electrode ear (21) of the annular battery cell (2) being electrically connected to the positive electrode column (141), and the negative electrode ear (22) of the annular battery cell (2) being electrically connected to the negative electrode column (142); or, One of the first end cover (11) and the second end cover (14) is provided with a positive electrode column (141), and the other is provided with a negative electrode column (142); the positive electrode ear (21) at one end of the annular battery cell (2) is electrically connected to the positive electrode column (141), and the negative electrode ear (22) at the other end of the annular battery cell (2) is electrically connected to the negative electrode column (142).

8. The annular battery according to any one of claims 3 to 7, characterized in that: The outer peripheral wall (13) and the first end cover (11) are an integral structure, or the outer peripheral wall (13) and the first end cover (11) are fixed by welding.

9. The annular battery according to any one of claims 3 to 7, characterized in that: The inner circumferential wall (12) and the first end cover (11) are an integral structure, or the inner circumferential wall (12) and the first end cover (11) are fixed by welding.

10. The annular battery according to any one of claims 3 to 7, characterized in that: The maximum value of the straight-line distance between any two points on the cross section of the first hole (121) is 0.11-0.65 of the maximum value of the straight-line distance between any two points on the cross section of the peripheral wall (13).

11. The annular battery according to claim 10, characterized in that: The maximum value of the straight-line distance between any two points on the cross section of the first hole (121) is 5 mm to 30 mm.

12. The annular battery according to claim 11, characterized in that: The maximum value of the straight-line distance between any two points on the cross section of the first hole (121) is 8 mm to 25 mm.

13. The annular battery according to claim 12, characterized in that: The maximum value of the straight-line distance between any two points on the cross section of the first hole (121) is 10 mm to 15 mm.

14. The annular battery according to any one of claims 2 to 7, characterized in that: A plurality of heat dissipation protrusions (122) are arranged on the hole wall of the first hole (121).

15. The annular battery according to claim 14, characterized in that: Each of the heat dissipation protrusions (122) is an annular protrusion arranged around the hole wall, or a dot-shaped protrusion or a columnar protrusion evenly distributed on the hole wall.

16. The annular battery according to any one of claims 2 to 7, characterized in that: The annular battery further comprises an annular battery core (2), wherein the annular battery core (2) is sleeved on the outside of the inner peripheral wall (12), and an insulating member is provided between the outer side surface of the inner peripheral wall (12) and the inner side surface of the annular battery core (2).

17. The annular battery according to claim 16, characterized in that: The insulating member comprises a layered structure (3) coated on the outer side of the inner peripheral wall (12); or, The insulating member comprises an annular structure (4) arranged at at least one end of the inner peripheral wall (12).

18. The annular battery according to any one of claims 2 to 7, characterized in that: The cross section of the outer peripheral wall (13) and / or the inner peripheral wall (12) is circular, regular polygonal, elliptical or non-equilateral polygonal.

19. The annular battery according to claim 18, characterized in that: The cross section of the first hole (121) is circular, regular polygonal, elliptical or non-equilateral polygonal.

20. The annular battery according to claim 7, characterized in that: The cross section of the annular battery core (2) is circular, regular polygonal, elliptical or non-equilateral polygonal.

21. A battery module, characterized in that: The invention comprises a plurality of annular batteries according to any one of claims 1 to 20, wherein the plurality of annular batteries are connected in series and / or in parallel.

22. An electrical equipment, characterized in that: Comprising a plurality of annular batteries as described in any one of claims 1 to 20; or, comprising the battery module as described in claim 21.

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