CN220121912U - Cylindrical battery cell and electronic equipment comprising same - Google Patents

Abstract

The utility model provides a cylindrical battery cell and an electronic device comprising the same, wherein the cylindrical battery cell comprises: the electrode assembly is arranged in the shell in a sealing way, and a winding core through hole is formed in the center of the electrode assembly; the pipe body is arranged in the winding core through hole in a penetrating mode, and the outer side wall of the pipe body is coated with a buffer layer; the buffer layer is configured to support a wall of the core through hole. The cylindrical battery cell can buffer the expansion force of the pole piece during expansion, avoid the pole piece from being broken, and avoid the collapse of the position of the through hole of the winding core, thereby improving the safety performance of the cylindrical battery cell.

Description

Cylindrical battery cell and electronic equipment comprising same

Technical Field

The utility model relates to the technical field of batteries, in particular to a cylindrical battery cell and electronic equipment comprising the same.

Background

Energy conservation and environmental protection are advantages of electric vehicles, and in recent years, cylindrical batteries are increasingly applied to electric vehicles, and market acceptance of the cylindrical batteries is also higher. In the cyclic process of charge and discharge, cathode and anode material particles in the cylindrical battery cell can expand, especially anode materials, and when the cylindrical battery cell expands due to the existence of a central hole, the position of an inner ring pole piece close to the central hole is unsupported in the cyclic process, and collapse is easy to occur at the position of the central hole, so that the damage of an electrode assembly is caused, and the safety risk exists. In order to solve this problem, in the prior art, a support member, such as a rigid central tube, is usually implanted in the central hole, but this approach can lead to no release of the expansion force of the inner ring pole piece, eventually causing the pole piece to break, and also presents a safety risk.

Disclosure of Invention

In view of the above drawbacks of the prior art, the present utility model provides a cylindrical battery cell, so as to reduce the safety risk problem caused by expansion of the pole piece during the charging and discharging process of the cylindrical battery cell.

To achieve the above and other related objects, the present utility model provides a cylindrical cell comprising: the electrode assembly is arranged in the shell in a sealing way, and a winding core through hole is formed in the center of the electrode assembly; the pipe body is arranged in the winding core through hole in a penetrating mode, and the outer side wall of the pipe body is coated with a buffer layer; the buffer layer is configured to support a wall of the core through hole.

In one example of a cylindrical cell of the present utility model, the buffer layer is configured to have adsorption properties for an electrolyte.

In an example of the cylindrical cell of the present utility model, the thickness of the buffer layer is 1-2 mm.

In an example of the cylindrical battery cell of the present utility model, a plurality of through holes are formed in the side wall of the tube body, and the plurality of through holes penetrate through the side wall of the tube body.

In one example of the cylindrical cell of the present utility model, the cross-sectional area of the single through hole is 0.5-30 mm ² 。

In an example of the cylindrical battery cell, the diameter of the tube body is 3-5 mm, and the wall thickness of the tube body is 0.2-1 mm.

In one example of the cylindrical cell of the present utility model, the tube body extends beyond the winding core through hole.

In an example of the cylindrical battery cell of the present utility model, the material of the tube body is PE or ceramic.

In an example of the cylindrical battery cell of the present utility model, the material of the buffer layer is foamed silica gel or cellulose aerogel.

The utility model also provides electronic equipment comprising the cylindrical battery cell.

According to the cylindrical battery cell, the pipe body is arranged in the through hole of the winding core in a penetrating way, so that when the cylindrical battery cell is charged and discharged, the expansion of the pole piece can be supported at the position of the through hole of the winding core, the probability of collapse of the electrode assembly at the position of the through hole of the winding core is reduced, and the safety and the cycle life of the cylindrical battery cell are improved; meanwhile, the outer side wall of the pipe body is coated with the buffer layer, and the buffer layer is configured to support the hole wall of the winding core through hole; therefore, the buffer layer can provide buffer force when the pole piece expands, so that the expansion force of the pole piece can be released, the probability of pole piece fracture is reduced, and the safety of the cylindrical battery is further improved.

Drawings

In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the utility model, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a cross-sectional view of the overall structure of an embodiment of a cylindrical cell of the present utility model;

FIG. 2 is a schematic top view of an electrode assembly in a housing according to one embodiment of the present utility model;

FIG. 3 is a schematic diagram showing the mounting position of the buffer layer on the tube in an embodiment of the cylindrical cell of the present utility model;

FIG. 4 is a schematic view of a tube structure of an embodiment of a cylindrical cell according to the present utility model;

fig. 5 is a schematic view of a tube structure of another embodiment of the cylindrical cell of the present utility model.

Description of element reference numerals

100. A cylindrical cell; 110. a housing; 111. an end wall; 112. a sidewall; 120. an electrode assembly; 1201. a winding core through hole; 1202. a positive electrode sheet; 1203. a negative electrode plate; 1204. a diaphragm; 130. a tube body; 1301. a through hole; 1302. a central bore; 140. a buffer layer; 150. an end cap; 160. a seal; 170. a pole; 180. a positive electrode current collecting plate; 190. a negative electrode current collecting plate.

Detailed Description

Other advantages and effects of the present utility model will become apparent to those skilled in the art from the following disclosure, which describes the embodiments of the present utility model with reference to specific examples. The utility model may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present utility model. It should be noted that the following embodiments and features in the embodiments may be combined with each other without conflict. It is also to be understood that the terminology used in the examples of the utility model is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the utility model. The test methods in the following examples, in which specific conditions are not noted, are generally conducted under conventional conditions or under conditions recommended by the respective manufacturers.

Where numerical ranges are provided in the examples, it is understood that unless otherwise stated herein, both endpoints of each numerical range and any number between the two endpoints are significant both in the numerical range. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs and to which this utility model belongs, and any method, apparatus, or material of the prior art similar or equivalent to the methods, apparatus, or materials described in the examples of this utility model may be used to practice the utility model.

It should be understood that the terms such as "upper," "lower," "left," "right," "middle," and "a" and the like are used in this specification for descriptive purposes only and not for purposes of limitation, and that the utility model may be practiced without materially departing from the novel teachings and without departing from the scope of the utility model.

Referring to fig. 1 to 4, the present utility model provides a cylindrical battery cell 100 and an electronic device including the same, where the cylindrical battery cell 100 can provide a supporting force for a position of a core through hole 1201 when a pole piece is expanded, reduce a probability of collapsing of the pole piece at the position of the core through hole 1201, and provide a buffering force when the pole piece is expanded, and reduce a probability of breaking of the pole piece, so as to improve safety of the cylindrical battery cell 100.

Referring to fig. 1, the cylindrical battery cell 100 includes: a case 110, an electrode assembly 120, and a tube 130. The case 110 has a receiving cavity formed therein for receiving the electrode assembly 120, an electrolyte (not shown), and other components, and the receiving cavity may be open at one end or open at both ends. Specifically, the shape of the case 110 may be determined according to the specific size of the electrode assembly 120. The material of the housing 110 may be various, such as copper, iron, aluminum, stainless steel, aluminum alloy, etc.

Referring to fig. 1 and 2, the electrode assembly 120 is sealingly mounted in the case 110, and the specific form of the seal is not limited. The electrode assembly 120 is a component in the cell where electrochemical reactions occur. One or more electrode assemblies 120 may be contained within the case 110. The electrode assembly 120 is formed mainly of a positive electrode sheet 1202 and a negative electrode sheet 1203 wound or stacked, and a separator 1204 is generally provided between the positive electrode sheet 1202 and the negative electrode sheet 1203. The portions of the positive electrode tab 1202 and the negative electrode tab 1203 having active materials constitute the main body of the electrode assembly 120, and the portions of the positive electrode tab 1202 and the negative electrode tab 1203 having no active materials constitute the tabs, respectively.

Specifically, referring to fig. 1, in an example of the cylindrical battery cell 100 of the present utility model, a case 110 includes an end wall 111 and a side wall 112 surrounding the end wall 111, the side wall 112 and the end wall 111 together enclose a housing cavity with one end closed and the other end open, an end cap 150 is sealed at the opening of the housing cavity by a sealing member 160, a post 170 is electrically connected with a positive electrode tab of an electrode assembly 120 by a positive electrode current collecting disc 180, a negative electrode tab of the case 110 and a negative electrode tab of the electrode assembly 120 are electrically connected by a negative electrode current collecting disc 190, the case 110 is negatively charged integrally, and a positive electrode post 170 and an end wall 111 of the case 110 are simultaneously provided on one side of the post 170, so that the post 170 and the end wall 111 respectively form a positive electrode and a negative electrode of the battery cell to realize the same side of the positive electrode and the negative electrode. The end wall 111 of the closed end of the housing 110 is provided with a through pole 170 mounting hole, and the pole 170 is inserted into the pole 170 mounting hole in a sealed and insulating manner, and the mounting manner of the pole 170 on the housing 110 is not limited as long as the sealing insulation between the pole 170 and the housing 110 can be realized. Such a case 110 structure can improve installation efficiency, and is more excellent in assemblability and sealability than the case 110 form having both ends open.

Referring to fig. 1 to 3, in an example of the cylindrical battery cell 100 of the present utility model, the cylindrical battery cell 100 further includes a tube body 130, the tube body 130 is inserted into a core through hole 1201 formed by winding the positive pole piece 1202 and the negative pole piece 1203, one end of the tube body 130, which is close to the pole 170, is abutted to the positive current collecting plate 180, and one end of the tube body 130, which is far away from the pole 170, is flush with the end face of the core through hole 1201 or is higher than the end face of the core through hole 1201, so that the length of the core through hole 1201 can be covered by the tube body 130 in the length direction, and the hole wall of the core through hole 1201 can be supported, thereby ensuring the cylindricity of the core through hole 1201. The pipe body 130 is of a hollow structure with a certain wall thickness, a central hole 1302 is formed in the center of the pipe body 130, and the pipe body 130 can be of a hollow round pipe structure or a polygonal hollow structure; preferably, referring to fig. 2 to 4, in an example of the present utility model, the tube body 130 is a hollow circular tube structure, which can effectively reduce the overall mass of the battery cell on one hand, and the cylindrical outer surface is not easy to damage the pole piece when being extruded by the electrode assembly on the other hand; the outer side wall of the pipe body 130 is coated with a buffer layer 140, and the buffer layer 140 completely covers the outer side wall surface of the pipe body 130; the buffer layer 140 may be coated on the outer sidewall of the tube body 130 by means including, but not limited to, bonding; the material of the buffer layer 140 is not limited, and may be any material capable of playing a role of buffering, for example, a silica gel material, a rubber material, a foam material, or the like; the buffer layer 140 abuts against the hole wall of the core through hole 1201, and is used for supporting the hole wall of the core through hole 1201.

It should be noted that, during the charge and discharge cycle, the cylindrical battery cell 100 may bring about a "respiration effect" of the internal pressure of the electrode assembly 120 due to the volume change of the positive and negative electrode materials, that is, a volume expansion during charging and a volume contraction during discharging. Because of the restraining effect of the side wall 112 of the case 110 on the outer side of the electrode assembly 120, the electrode assembly 120 may expand and bulge toward the inner side winding core through hole 1201, and collapse occurs, resulting in the damage of the electrode assembly 120 interface, thereby affecting the safety and cycle life of the cylindrical battery cell 100.

According to the utility model, the pipe body 130 with the buffer layer 140 coated on the outer side wall is arranged in the core through hole 1201, so that on one hand, the hole wall of the core through hole 1201 can be supported, the pole piece of the inner ring of the electrode assembly 120 is prevented from retracting towards the inner side of the core through hole 1201 when expanding, the position of the core through hole 1201 is prevented from collapsing, the damage of the interface of the electrode assembly 120 is reduced, the safety and the sequential service life of the cylindrical battery cell 100 are improved; on the other hand, the buffer layer 140 is arranged between the winding core through hole 1201 and the pipe body 130, and the buffer layer 140 can provide buffer force in the expansion process of the electrode assembly 120, so that the expansion force of the pole piece is released, rigid contact between the pole piece and the pipe body 130 is prevented when the pole piece expands, the probability of expansion fracture of the pole piece is reduced, and the safety of the cylindrical battery is further improved. In addition, a welding head may protrude from the central hole 1302 of the tube body 130 to a welding position of the positive electrode collector plate 180 and the electrode post 170, facilitating torque welding of the electrode post 170 and the positive electrode collector plate 180 inside the electrode assembly 120. When the tube 130 is not disposed in the core through hole 1201, the welding head may extend into the core through hole 1201, and torque welding is performed between the post 170 and the positive electrode current collecting plate 180, but the hole wall of the core through hole 1201 has a cylindricity not higher than that of the central hole 1302 of the tube 130, so that the welding head is easily damaged during the extending process. And when the welding head extends into the central hole 1302 of the pipe body 130, the welding head is not contacted with the pole piece of the inner ring, so that the problem that the pole piece is damaged by the welding head is avoided.

Referring to fig. 2, in an example of the cylindrical cell 100 of the present utility model, the buffer layer 140 is configured to have adsorption property to the electrolyte. So arranged, the buffer layer 140 can adsorb free electrolyte in the electrode sheet during the injection of electrolyte into the electrode assembly 120, thereby storing a portion of the electrolyte; when the electrode assembly 120 works, the inner ring pole piece expands and compresses the buffer layer 140 inwards, and at this time, the buffer layer 140 can gradually release the stored electrolyte, so that the electrolyte consumed on the pole piece in the cyclic charge and discharge process of the electrode assembly 120 can be supplemented, and the cyclic performance of the cylindrical battery cell 100 is improved. Meanwhile, since the buffer layer 140 has adsorption performance, the electrolyte enriched at both ends of the electrode assembly 120 in the liquid injection process can be gradually adsorbed to the middle position of the electrode assembly 120 with less electrolyte absorption, so that the movement performance of material particles between electrode plates at both ends of the electrode assembly 120 can be improved, and the distribution of the electrolyte in the length direction of the electrode assembly 120 can be balanced, thereby further improving the cycle performance of the electrode assembly 120, and improving the safety performance and the service life of the cylindrical battery.

The greater the thickness of the buffer layer 140, the better the stress buffering effect, but correspondingly occupies more installation space of the pole pieces in the electrode assembly 120, thereby reducing the energy density per unit volume of the cylindrical battery cell 100; conversely, the smaller the thickness of the buffer layer 140, the less the stress buffering effect will be, but less installation space for the pole pieces in the electrode assembly 120 will be occupied, thereby reducing the impact on the energy density per unit volume of the cylindrical cell 100. In an example of the cylindrical battery cell 100 of the present utility model, the thickness of the buffer layer 140 may be any value within a range of 1-2 mm, for example, 1mm, 1.5mm or 2mm, and the thickness of the buffer layer 140 may be controlled within the above range, so that a certain stress buffering effect may be obtained, the requirement of stress release during expansion of the electrode sheet is met, and a larger installation space may not be occupied in the electrode assembly 120, so that the influence on the energy density per unit volume of the cylindrical battery cell 100 may be reduced. It should be noted that, in order to facilitate the installation of the buffer layer 140 in the core through hole 1201, and prevent the damage to the buffer layer 140 caused by the inner ring pole piece in the installation process, a certain gap is provided between the buffer layer 140 and the wall of the core through hole 1201, and the size of the gap is any value in the range of 0.5-2 mm, preferably 1mm. When the cylindrical battery cell 100 starts to perform charge-discharge circulation after liquid injection, at this time, with the expansion action of the pole piece, a gap between the buffer layer 140 and the hole wall of the core through hole 1201 disappears, and at this time, a certain extrusion force exists between the buffer layer 140 and the hole wall of the core through hole 1201 all the time, so as to extrude and fix the buffer layer 140 in the core through hole 1201. In addition, the thickness of the buffer layer 140 in the present embodiment refers to the thickness of the buffer layer 140 when not compressed in the core through hole 1201.

Referring to fig. 5, in an example of the cylindrical battery cell 100 of the present utility model, a plurality of through holes 1301 are formed on a sidewall of the tube 130, and the plurality of through holes 1301 penetrate through the sidewall of the tube 130. The shape of the through hole 1301 may be selected from a variety of shapes, such as a circle, an ellipse, a square, a rectangle, or a prism, and preferably, in consideration of the ease of processing the through hole 1301 on the sidewall, referring to fig. 5, the shape of the through hole 1301 is a circle in this embodiment. The through holes 1301 may be uniformly distributed or unevenly distributed on the sidewall of the pipe body 130, which is not particularly limited. Through set up the through-hole 1301 on the lateral wall of body 130, at electrode assembly 120 annotate the liquid in-process, can be full of electrolyte in the body 130, and the outside infiltration of electrolyte in the body 130 can be through the through-hole 1301 on the lateral wall in the inside pole piece of electrode assembly 120, and then can improve the infiltration effect of the inside electrolyte of electrode assembly 120, reduce inside electrolyte and not enough lead to electrode assembly 120 to take place the lithium phenomenon of separating to electrode assembly 120. Meanwhile, through holes 1301 are formed in the side wall of the pipe body 130, accumulation of electrolyte in the inner hole of the pipe body 130 can be reduced, and the utilization rate of the electrolyte in the electrode assembly 120 can be improved. Preferably, in order to obtain a better wetting effect of the electrolyte inside the electrode assembly 120, referring to fig. 5, in this embodiment, the through holes 1301 are uniformly distributed on the sidewall of the tube body 130. It should be noted that, the sizes of the through holes 1301 of the circular structures on the side wall of the pipe body 130 may be equal or different, and in consideration of the efficiency and cost of processing the through holes 1301, in this embodiment, the sizes of the through holes 1301 on the side wall of the pipe body 130 are equal.

The larger the cross-sectional area of the through hole 1301 on the sidewall of the tube body 130, the faster the electrolyte flows from the through hole 1301, and the better the electrolyte impregnating effect inside the electrode assembly 120 during the injection process, but the overall supporting strength of the tube body 130 may be reduced. Preferably, in an example of the cylindrical cell 100 of the present utility model, the cross-sectional area of the single through hole 1301 is 0.5 to 30mm ² Any number within the range may be, for example, 0.5mm ² 、5mm ² 、15mm ² Or 30mm ² And the like, the cross-sectional area of the through hole 1301 is controlled within the range, so that the requirement of the speed of the electrolyte flowing from the through hole 1301 can be met, the inside of the electrode assembly 120 can obtain better electrolyte infiltration effect, and the side wall of the tube body 130 can be provided withAnd the support strength is certain, the collapse of the position of the through hole 1201 of the winding core during the expansion of the pole piece is prevented, and the safety requirement of the cylindrical battery cell 100 is met.

In an example of the cylindrical cell 100 of the present utility model, the diameter of the tube 130 may be any value in the range of 3 to 5mm, for example, 3mm, 4mm, 5mm, or the like, and the wall thickness of the tube 130 may be any value in the range of 0.2 to 1mm, for example, 0.2mm, 0.5mm, 0.7mm, 1mm, or the like. The diameter of the tube body 130 is controlled within the range of 3-5 mm, and the wall thickness of the tube body 130 is controlled within the range of 0.2-1 mm, so that the arrangement can meet the requirement of the support strength of the tube body 130, ensure the safety performance of the cylindrical battery cell 100, occupy no larger internal space of the electrode assembly 120 and reduce the influence on the volume energy density of the cylindrical battery cell 100; on the other hand, the inner diameter of the tube 130 is sized to meet the size requirements of the weld head to enable the weld head to complete a torque weld between the positive current collector plate 180 and the post 170.

On the premise that the wall thickness of the pipe body 130 meets the requirement of supporting strength, the same pipe body 130 diameter is adopted, the larger the wall thickness of the pipe body 130 is, the smaller the inner hole diameter of the pipe body 130 is, and the smaller the welding head specification size which can be allowed to pass is, so that the welding efficiency between the pole 170 and the positive electrode current collecting disc 180 is lower. Otherwise, the effect is opposite. In one example of a cylindrical cell 100 of the present utility model, the wall thickness of the tube 130 may be any value in the range of 0.2 to 0.5mm, such as 0.2mm, 0.3mm, 0.4mm, 0.5mm, etc. The wall thickness of the pipe body 130 is controlled within the range of 0.2-0.5 mm, so that the side wall of the pipe body 130 can be guaranteed to have certain supporting strength, the requirement of the internal expansion force of the electrode assembly 120 is met, the inner hole of the pipe body 130 can allow welding heads with larger specification and size to pass through, and the efficiency requirement of torque welding between the pole 170 and the positive electrode current collecting disc 180 is met.

In the cylindrical battery cell 100 of the present utility model, the height direction of the tube body 130 exceeds the core through hole 1201, and the tube body 130 may only exceed the core through hole at the end facing the end cap 150, or both ends of the tube body 130 may exceed the core through hole 1201 in the height direction. By the arrangement, when the end cover 150 side is placed vertically downwards in the assembly process of the cylindrical battery cell 100, free electrolyte in the electrode assembly 120 can accumulate on the end cover 150 side, and at the moment, the buffer layer 140 on the part, which is beyond the winding core through hole 1201, of the pipe body 130 can adsorb the electrolyte accumulated on the end cover 150 side and transfer the electrolyte to the electrolyte shortage position in the electrode assembly 120, so that the electrolyte is distributed more uniformly in the battery cell, and meanwhile, the accumulation of the electrolyte at the end part of the battery cell is reduced.

In the cylindrical battery cell 100 of the present utility model, the material of the tube body 130 may be any insulating material with a certain supporting strength, and specific materials can be flexibly selected by those skilled in the art according to actual needs. In an example of the cylindrical battery cell 100 of the present utility model, the tube 130 is made of PE, such as high-density polyethylene, low-density polyethylene, etc. Because the PE material has higher chemical stability and better corrosion resistance, the pollution of electrolyte can not be caused in the use process, so that the service life of the cylindrical battery cell 100 can be prolonged; meanwhile, the PE material has better machining performance and higher strength and toughness, so that the requirement of the internal expansion force of the electrode assembly 120 on the cyclic stress of the tube 130 can be met; and the PE material is lighter in weight, so that the influence on the energy density in the unit mass of the cylindrical battery cell 100 can be reduced.

In an example of the cylindrical cell 100 of the present utility model, the tube 130 is made of ceramic. The ceramic material can be fiber porous ceramic, large-particle sintered ceramic, porous thermal barrier ceramic, composite heat insulation ceramic and the like. Because the ceramic material has better shock resistance and vibration resistance, when the cylindrical battery cell 100 is impacted by a larger external force in the use process, the tube body 130 is not easy to crack, so that the shock resistance of the electrode assembly 120 can be improved; meanwhile, the insulating property of the ceramic material is stable and cannot be reduced along with the use time, so that the stability of the charge and discharge performance of the electrode assembly 120 can be ensured. In addition, the ceramic material has high temperature resistance, so that when the electrode assembly 120 generates a large amount of heat in the working process, the supporting performance of the tube body 130 is not affected, and the normal use of the tube body 130 under the high temperature condition is ensured.

In the cylindrical battery cell 100 of the present utility model, the material of the buffer layer 140 may be any material having a certain stress buffering effect and having an adsorption property to the electrolyte, and specific materials can be flexibly selected by those skilled in the art according to actual needs. In an example of the cylindrical battery cell 100 of the present utility model, the material of the buffer layer 140 is foamed silica gel. On one hand, the foaming silica gel has uniform foaming, good stability and fine and uniform pore diameter of the generated foam, so that the foaming silica gel has stable adsorption performance on electrolyte and uniform adsorption in the use process, and is more beneficial to uniform distribution of the electrolyte in the electrode assembly 120; on the other hand, the foaming silica gel is nontoxic and noncorrosive, cannot pollute the electrolyte in the long-time use process, and ensures the stability of the electrolyte components, thereby ensuring the sequential service life of the cylindrical battery cell 100. In addition, because the foaming silica gel has good elasticity, the foaming silica gel has good retraction performance, can better meet the use requirement of the electrode assembly 120 on the cyclic expansion and retraction of the internal pole piece, and improves the stability of the adsorption performance in the use process of the buffer layer 140.

In an example of the cylindrical cell 100 of the present utility model, the buffer layer 140 is made of cellulose aerogel. Because the cellulose aerogel is an ultra-light solid material, the quality of the buffer layer 140 can be obviously reduced, and the energy density of the cylindrical battery cell 100 can be correspondingly improved; meanwhile, the compression retraction elasticity and the adsorption performance of the cellulose aerogel are excellent, and the compression rebound use requirement of the buffer layer 140 and the adsorption performance requirement of electrolyte can be well met.

It should be noted that, the connection manner between the buffer layer 140 and the tube 130 may be selected in various ways, as long as a stable and fixed connection of the buffer layer 140 on the sidewall of the tube 130 can be achieved, for example, the buffer layer 140 may be fixed on the sidewall of the tube 130 by an adhesive manner, or may be connected on the sidewall of the tube 130 by thermoforming. Preferably, in consideration of the cost of the fixed connection of the buffer layer 140 to the sidewall of the tube body 130, in an example of the present utility model, the buffer layer 140 is fixedly connected to the sidewall of the tube body 130 by means of adhesion.

In an example of the cylindrical battery cell 100 of the present utility model, the tube 130 is made of PE, the thickness of the side wall of the tube 130 is 0.5mm, the length is 110mm, and the outer diameter of the tube 130 is 4mm; in this embodiment, the material of the buffer layer 140 is foamed silica gel, the thickness of the foamed silica gel is 1mm when the foamed silica gel is not compressed, and the thickness of the buffer layer 140 is 110mm, and the buffer layer 140 is adhered to the side wall of the tube 130 through acrylic adhesive. The gap between the buffer layer 140 and the wall of the core through hole 1201 is 2mm, under which the inner ring pole piece does not damage the buffer layer 140 on the sidewall of the tube body 130 when the tube body 130 is mounted to the core through hole 1201, and at the same time does not occupy a large mounting space of the electrode assembly 120. In this embodiment, when the pole 170 expands in the cyclic charge and discharge process of the cylindrical battery cell 100, on one hand, the tube 130 can not only well relieve the expansion of the pole piece and reduce the fracture probability of the pole piece, but also avoid the collapse of the position of the core winding through hole 1201 and improve the safety performance of the cylindrical battery cell 100. On the other hand, since the buffer layer 140 can absorb a part of the electrolyte during the injection process of the electrode assembly 120, the infiltration effect of the electrolyte inside the electrode assembly 120 can be improved during the charge and discharge process of the electrode assembly 120, and the probability of lithium precipitation of the electrode assembly 120 due to insufficient infiltration of the electrolyte inside the electrode assembly 120 can be reduced.

In an example of the cylindrical battery cell 100 of the present utility model, the tube body 130 is made of ceramic material, the thickness of the sidewall of the tube body 130 is 0.4mm, the length is 68mm, the outer diameter of the tube body 130 is 5mm, circular through holes 1301 are uniformly distributed on the sidewall of the tube body 130, and the area of each through hole 1301 is 3.14mm ² . In this embodiment, the material of the buffer layer 140 is cellulose aerogel, and the thickness of the cellulose aerogel is 1mm and the length is 68mm; the cellulose aerogel is adhered and connected to the surface of the side wall of the pipe body 130 through acrylic rubber. The buffer layer 140 is 1mm from the wall of the central bore 1302. When the pole piece expands in the circulation process of the cylindrical battery cell 100, the tube 130 in the embodiment can well relieve the expansion of the pole piece and avoid the collapse at the position of the through hole 1201 of the winding core. And in the circulation process, when the inner ring pole piece expands and inwards extrudes the buffer layer 140, the buffer layer 140 can continuously release electrolyte into the inner ring pole piece, and the electrolyte can be adsorbed to the liquid shortage position inside the electrode assembly 120 under the capillary action, so that the circulation performance of the cylindrical battery cell 100 is improved.

The utility model also provides electronic equipment, which comprises a working part and a battery module or a battery pack, wherein the battery module or the battery pack comprises the cylindrical battery core. The working part is connected with the battery module or the battery pack to obtain electric energy support. The working part may be a unit part capable of acquiring electric energy of the battery module or the battery pack and making corresponding work, such as a blade rotating unit of a fan, a dust suction working unit of a dust collector, a wheel driving unit in an electric automobile, and the like. The electronic device may be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, an electric tool, and the like. The vehicle can be a fuel oil vehicle, a fuel gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle or a range-extended vehicle; spacecraft including airplanes, rockets, space planes, spacecraft, and the like; the electric toy includes fixed or mobile electric toys, such as a game machine, an electric car toy, an electric ship toy, and an electric airplane toy; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railroad power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete shakers, and electric planers, among others. The embodiment of the utility model does not limit the electronic device in particular.

In the cylindrical battery cell 100, the pipe body 130 with the buffer layer 140 coated on the outer side wall is arranged in the coil core through hole 1201, so that the collapse of a pole piece at the position of the coil core through hole 1201 can be avoided, and the safety performance of the cylindrical battery cell 100 is improved; the expansion force released in the expansion process of a part of the pole pieces can be buffered, so that the expansion force of the pole pieces is released, the probability of pole piece fracture is reduced, and the safety of the cylindrical battery is further improved; meanwhile, because the pipe body 130 is of a hollow structure, the welding head can extend into the welding position of the current collecting disc and the pole 170 from the center of the pipe body 130, so that torque welding is conveniently carried out on the pole 170 in the electrode assembly 120. Meanwhile, in the cylindrical battery cell 100 of the present utility model, the buffer layer 140 has the property of adsorbing electrolyte, so that a part of electrolyte can be adsorbed when the electrode assembly 120 is injected, and in the later period of circulation, when the inner ring pole piece expands to press the buffer layer 140 inwards, the buffer layer 140 can continuously release electrolyte into the inner ring pole piece of the electrode assembly 120, and the electrolyte can be adsorbed to the electrolyte shortage of the electrode assembly 120 by capillary action, so that the circulation performance of the cylindrical battery cell 100 is improved. Therefore, the utility model effectively overcomes some practical problems in the prior art, thereby having high utilization value and use significance. The above embodiments are merely illustrative of the principles of the present utility model and its effectiveness, and are not intended to limit the utility model. Modifications and variations may be made to the above-described embodiments by those skilled in the art without departing from the spirit and scope of the utility model. Accordingly, it is intended that all equivalent modifications and variations of the utility model be covered by the claims, which are within the ordinary skill of the art, be within the spirit and scope of the present disclosure.

Claims (10)

1. A cylindrical cell, comprising:

the shell body is provided with a plurality of grooves,

an electrode assembly hermetically installed in the case, the center of the electrode assembly being formed with a winding core through hole;

the pipe body is arranged in the winding core through hole in a penetrating way, and the outer side wall of the pipe body is coated with a buffer layer; the buffer layer is configured to support a wall of the core through hole.

2. The cylindrical cell of claim 1, wherein the buffer layer is configured to have adsorption properties for an electrolyte.

3. The cylindrical cell according to claim 2, wherein the thickness of the buffer layer is 1-2 mm.

4. A cylindrical cell according to any one of claims 1 to 3, wherein a plurality of through holes are provided in the side wall of the tube, a plurality of the through holes penetrating the side wall of the tube.

5. The cylindrical cell of claim 4, whereinWherein the cross-sectional area of each through hole is 0.5-30 mm ² 。

6. The cylindrical cell according to claim 1, wherein the diameter of the tube is 3-5 mm and the wall thickness of the tube is 0.2-1 mm.

7. The cylindrical cell of claim 6, wherein the tube body extends beyond the jellyroll through hole.

8. The cylindrical cell according to claim 1, wherein the tube is made of PE or ceramic.

9. The cylindrical battery cell according to claim 1, wherein the material of the buffer layer is foamed silica gel or cellulose aerogel.

10. An electronic device comprising a cylindrical cell as claimed in any one of claims 1 to 9.