Battery monomer and battery

Abstract

The utility model provides a battery monomer and a battery. The battery monomer comprises a shell, a first pole, a battery core assembly and a reference electrode, wherein the shell is provided with an accommodating cavity; the first pole column is arranged on the shell and is used for external electric connection of the battery monomers; the battery core assembly is packaged in the accommodating cavity of the shell; the reference electrode comprises a main body part and a handle part; two ends of the handle part are respectively connected with the main body part and the first pole; one ends, close to the main body part, of the main body part and the handle part are arranged in the battery core assembly in an insulating manner; the main body part is sheet-shaped and is provided with at least one through hole penetrating along the ion movement direction of the battery cell assembly. According to the battery monomer, the lithium precipitation condition in the battery monomer can be monitored more accurately in real time, and meanwhile, the influence of the reference electrode on charging and discharging of the battery monomer is also reduced, so that the comprehensive performance of the battery is effectively improved.

Description

Technical Field

[0001] The utility model relates to the field of new energy batteries, and in particular to a battery monomer and a battery. Background Art

[0002] In the global context, new energy vehicles have experienced rapid development. Taking lithium-ion power batteries as an example, lithium-ion batteries have been widely used in communication base stations, digital and electric vehicles due to their advantages such as high energy density, long cycle life and no memory effect. Lithium-ion power batteries are the core components of new energy vehicles. There are three main types of lithium-ion power batteries: square aluminum shell batteries, cylindrical batteries and soft pack batteries.

[0003] The new energy industry is developing rapidly, and people have put forward higher requirements for the fast charging performance and cycle life of new energy batteries, especially lithium-ion batteries and sodium-ion batteries. These requirements not only give higher expectations to the material system of the battery itself, but also require the battery to have higher safety performance.

[0004] Therefore, how to improve the safety and comprehensive performance of new energy batteries is a technical problem that needs to be urgently solved in this field. Utility Model Content

[0005] The main technical problem solved by the utility model is to provide a battery monomer with higher safety performance, so that the comprehensive performance of the battery is effectively improved.

[0006] According to the first aspect, the utility model provides a battery cell, including a shell, a first pole, a battery cell assembly and a reference electrode. Among them: the shell has a receiving cavity; the first pole is installed on the shell, and is used for external electrical connection of the battery cell; the battery cell assembly is encapsulated in the receiving cavity of the shell; the reference electrode includes a main body and a handle, and the two ends of the handle are respectively connected to the main body and the first pole; the main body and one end of the handle close to the main body are insulated and arranged in the battery cell assembly; the main body is in sheet shape, and the main body is provided with at least one through hole penetrating along the ion movement direction of the battery cell assembly.

[0007] In an optional embodiment, there are multiple via holes, and the multiple via holes are evenly distributed in the main body.

[0008] In an optional embodiment, the cross section of the via hole is circular or square, and the diameter / side length of the via hole is 10 μm to 1000 μm.

[0009] In an optional embodiment, the battery cell assembly includes a positive electrode sheet, a negative electrode sheet and a first separator arranged between the positive electrode sheet and the negative electrode sheet, and the battery cell also includes a second separator, and the second separator is arranged on the side of the first separator away from the positive electrode sheet or away from the negative electrode sheet; the main body is clamped between the first separator and the second separator; the outer surface of the handle extending outside the battery cell assembly has an insulating layer, or the handle is an insulating handle made of insulating material.

[0010] In an optional embodiment, the shell has a first through hole connected to the accommodating cavity; the battery cell also includes a first insulating member, the first insulating member is installed in the first through hole, and the melting point of the first insulating member is 80°C to 120°C.

[0011] In an optional embodiment, the shell also has a second through hole connected to the accommodating cavity, and the battery cell also includes a second insulating member, a second pole and a temperature detection member. The second insulating member is installed in the second through hole, and the temperature detection member is arranged in the accommodating cavity and electrically connected to the second pole to monitor the temperature of the battery cell; of the first insulating member and the second insulating member, one is sleeved on the outer peripheral surface of the first pole, and the other is sleeved on the outer peripheral surface of the second pole.

[0012] In an optional embodiment, the melting point of the second insulating member is 80°C to 120°C.

[0013] In an optional embodiment, the housing includes a cover plate and an outer shell having an opening, the cover plate is connected to the open end of the outer shell; and the first pole is arranged on the cover plate.

[0014] In an optional embodiment, an explosion-proof valve for releasing pressure in response to pressure is also provided on the housing.

[0015] According to a second aspect, the utility model further provides a battery, comprising at least one of the above-mentioned battery cells.

[0016] According to the battery cell of the above embodiment, a reference electrode is set inside the battery cell to monitor the potential of the battery cell in real time, and the structure of the reference electrode is improved. On the one hand, compared with the filamentary reference electrode, the main body is set to a sheet shape. Compared with the filamentary reference electrode, the main body has a larger surface area. At the same time, the presence of the via further increases the surface area of ​​the main body, which can provide more plating sites for lithium ions, which is conducive to the uniform electroplating of lithium on the copper mesh. During the use of the battery cell, the reference electrode can monitor the potential of the battery cell assembly in real time. The first pole is used for external electrical connection to transmit the electrical signal of the reference electrode, and then the lithium precipitation inside the battery cell can be monitored in real time, which is conducive to more accurate judgment of the battery capacity attenuation and the growth of lithium dendrites in the battery cell assembly. It can detect the use status and failure of each battery cell in real time and non-destructively. On the other hand, since the main body is provided with vias for ion transmission, when ions move between the positive electrode and the negative electrode, the ion transmission does not need to completely bypass the main body, thereby effectively shortening the ion movement path compared to the solid main body, reducing the influence of the reference electrode on the local lithium ion transmission speed and the influence on the normal use of the battery cell, thereby effectively improving the overall performance of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A three-dimensional structural diagram of a battery cell provided in some embodiments of the present utility model.

[0018] Figure 2 for Figure 1 Another perspective diagram of the battery cell in FIG.

[0019] Figure 3 for Figure 1 Schematic diagram of the explosion of a battery cell.

[0020] Figure 4 for Figure 3 Front view of the battery cell in .

[0021] Figure 5 for Figure 3 A further exploded view of a battery cell in Figure 1.

[0022] Figure 6 for Figure 5 Front view of the battery cell in .

[0023] Figure 7 Schematic diagram of a battery cell assembly and a reference electrode of a battery cell provided in some embodiments of the present invention.

[0024] Figure 8 A schematic structural diagram of a reference electrode of a battery cell provided in some embodiments of the present utility model.

[0025] Fig. 9 A schematic diagram of a first insulating member and a second insulating member of a battery cell provided in some embodiments of the present utility model.

[0026] Fig.10 Schematic diagram of a battery cell cover provided in some embodiments of the present invention equipped with a first insulating member and a second insulating member

[0027] Figure markings: 100-battery cell; 10-shell; 11-cover; 111-first through hole; 112-second through hole; 12-shell; 21-first pole; 22-second pole; 30-cell assembly; 31-positive pole ear; 32-negative pole ear; 40-reference electrode; 41-main body; 411-circular surface segment; 412-transition segment; 42-handle; 43-via; 51-first insulating member; 52-second insulating member; 53-base; 54-first extended edge; 55-second extended edge; 60-temperature detection member; 70-positive pole output portion; 80-explosion-proof valve. DETAILED DESCRIPTION

[0028] The present invention is further described in detail below by specific embodiments in conjunction with the accompanying drawings. Wherein similar elements in different embodiments adopt associated similar element numbers. In the following embodiments, many detailed descriptions are intended to enable the present application to be better understood. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can be replaced by other elements, materials, and methods. In some cases, some operations related to the present application are not shown or described in the specification, in order to avoid the core part of the present application being overwhelmed by too much description, and for those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations based on the description in the specification and the general technical knowledge in the art.

[0029] In addition, the features, operations or characteristics described in the specification can be combined in any appropriate manner to form various implementations. At the same time, the steps or actions in the method description can also be interchanged or adjusted in a manner that is obvious to those skilled in the art. Therefore, the various sequences in the specification and the drawings are only for the purpose of clearly describing a certain embodiment and are not meant to be a required sequence, unless otherwise specified that a certain sequence must be followed.

[0030] The serial numbers of the components in this document, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in this application, unless otherwise specified, include direct and indirect connections (couplings).

[0031] In the related art, capacity decay may occur in lithium-ion batteries and sodium-ion batteries during actual application cycles, among which lithium plating is one of the most important factors affecting capacity decay. Lithium plating is the precipitation of lithium dendrites on the surface of the negative electrode sheet of the battery cell assembly 30. The growth of lithium dendrites may pierce the diaphragm between the positive electrode sheet and the negative electrode sheet, causing an internal short circuit in the battery cell assembly 30. Lithium plating will not only reduce the capacity of the battery cell 100, but also cause safety hazards to the battery cell 100 during use. Therefore, how to improve the safety performance of new energy batteries is a technical problem that urgently needs to be solved in this field.

[0032] In order to improve the comprehensive performance of the battery cell 100, the utility model provides a battery cell 100, please refer to Figure 1 , Figure 5 and Figure 8 The battery cell 100 includes a shell 10, a first pole 21, a cell assembly 30 and a reference electrode 40. The shell 10 has a receiving cavity; the first pole 21 is mounted on the shell 10 for external electrical connection of the battery cell 100; the cell assembly 30 is encapsulated in the receiving cavity of the shell 10; the reference electrode 40 includes a main body 41 and a handle 42, and the two ends of the handle 42 are respectively connected to the main body 41 and the first pole 21; the main body 41 and the end of the handle 42 close to the main body 41 are both insulated and arranged in the cell assembly 30; the main body 41 is in sheet shape, and the main body 41 is provided with at least one through hole 43 that passes through the ion movement direction of the cell assembly 30.

[0033] According to the battery cell 100 of the above embodiment, a reference electrode 40 is set in the battery cell 100 to monitor the potential of the battery cell 100 in real time, and the structure of the reference electrode 40 is improved. On the one hand, compared with the filamentary reference electrode 40, the main body 41 is set to be sheet-shaped. Compared with the filamentary reference electrode 40, the main body 41 has a larger surface area. At the same time, the presence of the via 43 further increases the surface area of ​​the main body 41, which can provide more plating sites for lithium ions, which is conducive to the uniform electroplating of lithium on the copper mesh. During the use of the battery cell 100, the reference electrode 40 can monitor the potential of the battery cell assembly 30 in real time, and the first pole 21 is used for external electrical connection to transmit the electrical signal of the reference electrode 40, so as to monitor the lithium deposition inside the battery cell 100 in real time, which is conducive to more accurate judgment of the battery capacity attenuation and the growth of lithium dendrites in the battery cell assembly 30, and can detect the use status and failure of each battery cell 100 in real time and non-destructively. On the other hand, since the main body 41 is provided with a via 43 for ion transmission, when ions move between the positive electrode and the negative electrode, the ion transmission does not need to completely bypass the main body 41, thereby effectively shortening the movement path of the ions compared to the solid main body 41, reducing the influence of the reference electrode 40 on the local lithium ion transmission speed and the influence on the normal use of the battery cell 100, thereby effectively improving the overall performance of the battery.

[0034] It should be noted that, in some embodiments, the first pole 21 can be an integral structure with the reference electrode 40; in some embodiments, the first pole 21 can also be formed on the shell 10 and welded to the reference electrode 40; in some embodiments, the first pole 21, the reference electrode 40 and the shell 10 are three independent components, which is not limited in the present utility model.

[0035] In different embodiments, the reference electrode 40 can be any reference electrode 40 that can be implemented in the prior art. Common materials of the reference electrode 40 include silver / silver chloride electrode, copper / copper ion electrode, platinum electrode, mercury / mercury ion electrode, etc. The material selection of the reference electrode 40 can refer to the relevant technology and will not be described here. For example, in some embodiments, the reference electrode 40 can be made of metal materials such as copper and platinum.

[0036] In some embodiments, the handle 42 of the reference electrode 40 can be a filamentary structure. The filamentary handle 42 is light and small in structure, and has little impact on the internal structure of the battery cell assembly 30 . It can further reduce the impact of the reference electrode 40 on ion transmission, which is conducive to a more realistic reflection of the internal conditions of the battery cell assembly 30 .

[0037] In some embodiments, the handle 42 of the reference electrode 40 may also be in a sheet shape, and the handle 42 and the main body 41 may be parallel or coplanar, and the width of the handle 42 is smaller than the width of the main body 41 .

[0038] In some embodiments, the main body 41 includes a circular segment 411 and a transition segment 412, and the through hole 43 is provided on the circular segment 411. The transition segment 412 connects the circular segment 411 and the handle 42. The center angle of the circular segment 411 is between 180° and 360°. For example, it can be 200°, 260°, 300°, 320°, etc. In some embodiments, the center angle of the circular segment 411 is between 300° and 360°.

[0039] In some embodiments, the number of vias 43 may be one or more than two. Figure 8 In some embodiments, there are multiple vias 43, and the multiple vias 43 are evenly distributed on the main body 41, so that lithium ions can be more evenly plated on the main body 41 of the reference electrode 40. In some embodiments, the sizes of the multiple vias 43 can also be set to be consistent.

[0040] In some embodiments, the cross-section of the via hole 43 may be a polygon such as a triangle, a rectangle, a square, or an irregular shape.

[0041] In some embodiments, in order to facilitate processing and ensure the consistency of multiple vias 43, the cross-section of the via 43 can be circular or square, and the diameter / side length of the via 43 is 10μm to 1000μm. Controlling the diameter of the via 43 to 10μm to 1000μm can effectively expand the surface area of ​​the main body 41.

[0042] In different embodiments, the two technical features of "multiple via holes 43 are evenly distributed in the main body 41" and "the cross-section of the via hole 43 can be circular or square, and the diameter / side length of the via hole 43 is 10μm to 1000μm" may be satisfied by only one of them or both, and the present utility model does not make specific limitations thereon.

[0043] In some embodiments, the battery cell assembly 30 includes a positive electrode sheet, a negative electrode sheet, and a first diaphragm disposed between the positive electrode sheet and the negative electrode sheet. In order to achieve insulation between the reference electrode 40, the positive electrode sheet, and the negative electrode sheet, the battery cell 100 also includes a second diaphragm, which is disposed on the side of the first diaphragm away from the positive electrode sheet or away from the negative electrode sheet; the main body 41 is sandwiched between the first diaphragm and the second diaphragm; the outer surface of the handle 42 extending outside the battery cell assembly 30 has an insulating layer, or the handle 42 is an insulating handle made of insulating material. An additional layer of the second diaphragm is placed at the reference electrode 40, and along the thickness direction of the battery cell assembly 30, the structure at the reference electrode 40 is negative electrode sheet / first diaphragm / reference electrode 40 / second diaphragm / positive electrode sheet, or negative electrode sheet / second diaphragm / reference electrode 40 / first diaphragm / positive electrode sheet. At the same time, the setting of the insulating handle or insulating layer can effectively inhibit lithium ion electroplating at the end of the reference electrode 40 close to the first pole 21, thereby effectively avoiding short circuit and failure caused by electrical conduction between the first pole 21 and other electrodes, thereby improving the stability of the battery cell 100.

[0044] It should be noted that the insulation between the handle 42 and the battery cell assembly 30 can be achieved by the first diaphragm and the second diaphragm, or by an additional insulating structure in cooperation with the first diaphragm. Figure 8 The handle 42 is an insulating handle made of insulating material, and the insulating handle can be directly insulated from the battery cell assembly 30 .

[0045] The insulating layer may be an insulating paint layer, an insulating coating, an insulating material layer, etc., and may be any feasible structure in the prior art, which is not limited in this embodiment.

[0046] It should be noted that “extending into the battery cell assembly 30 ” refers to the portion of the battery cell assembly 30 where the positive electrode sheet and the negative electrode sheet are opposite, that is, the region where the positive electrode sheet and the negative electrode sheet have active material layers.

[0047] In addition, in some embodiments, the insulating layer may also extend to the end of the handle 42 extending into the battery cell assembly 30 and away from the main body 41, so as to further improve the insulation safety of the battery cell assembly 30 and the handle 42 at the boundary between the battery cell assembly 30 and the handle 42 extending into and out of the battery cell assembly 30. In some embodiments, the outer peripheral surface of the entire portion of the handle 42 may have an insulating layer, so that lithium ions are more evenly plated on the main body 41.

[0048] It should be noted that the battery cell assembly 30 can be a laminated battery cell or a wound battery cell. Taking the wound battery cell as an example, the step of placing the reference electrode 40 into the battery cell assembly 30 can be performed during the winding process of the battery cell assembly 30, or after the battery cell assembly 30 is wound. In some embodiments, the reference electrode 40 is placed between the negative electrode sheet and the first diaphragm in the winding process of the core. The process of placing the reference electrode 40 in the winding process can minimize the damage to the core caused by human factors in the process compared with the traditional process of disassembling the wound core and placing the reference electrode 40.

[0049] In addition, the number of reference electrodes 40 can be one or more than two. When more than two reference electrodes 40 are provided, the lithium deposition of the negative electrode sheets at multiple positions inside the battery cell 100 can be detected in real time. When the negative electrode reaches the electrode potential of the reference electrode 40, it is determined that lithium deposition occurs at the corresponding position.

[0050] Similar to the prior art, the battery cell assembly 30 also includes a positive pole tab 31 and a negative pole tab 32, and both the positive pole tab 31 and the negative pole tab 32 can be a full pole tab structure or a non-full pole tab structure. The battery cell 100 also has a positive output portion 70 and a negative output portion, and the positive output portion 70, the negative output portion and the first pole 21 need to be electrically isolated from each other. The utility model does not limit the design scheme that can be implemented for the battery cell 100, and any feasible design scheme in the relevant technology can be referred to. For example, in some embodiments, the shell 10 can be directly used as one of the positive output portion 70 and the negative output portion, and the shell 10 is insulated from the remaining two output structures. For example, in some embodiments, the shell 10 can also be directly electrically connected to the first pole 21, and the shell 10 can be insulated from the positive output portion 70 and the negative output portion.

[0051] In some embodiments, in order to better manage the thermal performance of the battery cell 100 and effectively improve the safety factor, safety performance and reliability of the battery cell 100, please refer to Figure 5 and Fig.10 The housing 10 has a first through hole 111 connected to the accommodating cavity; the battery cell 100 also includes a first insulating member 51, which is installed in the first through hole 111, and the melting point of the first insulating member 51 is 80°C to 120°C. The first insulating member 51 is a low melting point component, which can melt in response to the internal temperature of the battery cell 100. If the battery cell 100 has thermal runaway, the internal temperature of the battery cell 100 will rise. When the temperature reaches the melting point of the first insulating member 51, the first insulating member 51 melts / melts, and the accommodating cavity of the housing 10 is connected to the outside through the first through hole 111, which plays a role in timely pressure relief, preventing the battery cell 100 from exploding due to thermal runaway and excessive internal pressure, thereby effectively improving the safety performance of the battery cell 100.

[0052] It should be noted that, in some embodiments, the first insulating member 51 and the first pole 21 can be arranged on the shell 10 at intervals and independently. If the shell 10 is a metal shell 10 and the first pole 21 needs to be insulated on the shell 10, the insulation between the first pole 21 and the shell 10 can be achieved by an additional insulating component.

[0053] In some embodiments, in order to monitor the temperature changes inside the battery cell 100 in real time, the shell 10 also has a second through hole 112 connected to the accommodating cavity, and the battery cell 100 also includes a second insulating member 52, a second pole 22 and a temperature detection member 60. The second insulating member 52 is installed in the second through hole 112, and the temperature detection member 60 is arranged in the accommodating cavity and electrically connected to the second pole 22 to monitor the temperature of the battery cell 100; of the first insulating member 51 and the second insulating member 52, one is sleeved on the outer peripheral surface of the first pole 21, and the other is sleeved on the outer peripheral surface of the second pole 22. On the one hand, by arranging the temperature detection component 60 inside the battery cell 100, the second pole 22 transmits the electrical signal of the temperature detection component 60 to the outside of the battery cell 100, so that the temperature change inside the battery cell 100 can be monitored in real time; on the other hand, by sleeve-connecting the first insulating component 51 and the second insulating component 52 with the first pole 21 and the second pole 22 one by one, the installation and insulation of the first pole 21 and the second pole 22 are achieved, and the positions of the first insulating component 51, the second insulating component 52, the first pole 21 and the second pole 22 can be relatively concentrated, thereby reducing the occupied space on the shell 10.

[0054] Similarly, in some embodiments, the second pole 22 can be an integral structure with the temperature detection element 60; in some embodiments, the second pole 22 can also be formed on the shell 10 and welded and fixed to the temperature detection element 60; in some embodiments, the second pole 22, the temperature detection element 60 and the shell 10 are three independent components, which is not limited in the present utility model.

[0055] In some embodiments, the first pole 21 may be interference fit with the first insulating member 51 , and the second pole 22 may also be interference fit with the second insulating member 52 .

[0056] The temperature detection element 60 can be any component in the prior art that can detect temperature and transmit electrical signals, for example, it can be a thermocouple, a temperature sensor, etc., as long as it can detect the temperature change inside the battery cell 100 or a certain position of the battery cell assembly 30.

[0057] In some embodiments, the temperature detection member 60 may extend into the battery cell assembly 30 and be insulated between the positive electrode sheet and the negative electrode sheet. Figure 7The battery cell assembly 30 can be a wound cylindrical battery cell, the first pole 21 and the second pole 22 are both arranged on the cover plate 11, and one end of the temperature detection member 60 is connected to the second pole 22 and the other end extends into the center hole of the battery cell assembly 30.

[0058] In some embodiments, please refer to Figure 1 and Figure 3 The first insulating member 51 is sleeved on the outer circumference of the first pole 21 , and the second insulating member 52 is sleeved on the outer circumference of the second pole 22 .

[0059] In some embodiments, taking the installation of the first insulating member 51 in the first through hole 111 as an example, in order to facilitate production and manufacturing, the initial shape of the first insulating member 51 is T-shaped, including a connecting base 53 and a first extension edge 54, the base 53 has a center hole for installing the first pole 21, and the first extension edge 54 extends along the circumference of the base 53. After the base 53 is installed in the first through hole 111, the end of the base 53 away from the first extension edge 54 extends out of the first through hole 111, and the end of the base 53 extending out of the first through hole 111 is formed by hot pressing or other processes. The second extension edge 55 is formed, and the first insulating member 51 is positioned and installed on the shell 10 by the first extension edge 54 and the second extension edge 55. The final shape of the first insulating member 51 is an I-shaped structure.

[0060] In some embodiments, in order to further improve the safety performance and reliability of the battery cell 100, the melting point of the second insulating member 52 can also be 80°C to 120°C. When the temperature of the battery cell 100 rises due to thermal runaway, the first insulating member 51 and the second insulating member 52 with a low melting point will melt / melt first, so that the pressure inside the battery cell 100 can be released first from the first electrode 21 and the second electrode 22, thereby effectively avoiding serious thermal runaway accidents.

[0061] Please refer to Figure 1 and Figure 3 In some embodiments, in order to facilitate the assembly of the battery cell assembly 30 and the housing 10, the housing 10 includes a cover plate 11 and a housing 12 having an opening, the cover plate 11 is connected to the open end of the housing 12, the cover plate 11 encapsulates the housing 12, and the housing 12 and the cover plate 11 together form a receiving cavity. The first pole 21 is provided on the cover plate 11, and by at least making the connection between the first pole 21 and the reference electrode 40 at the open end of the housing 12, the connection and fixation of the first pole 21 and the reference electrode 40 are facilitated, and the obstacles to assembly are reduced.

[0062] In different embodiments, the second pole 22 can be arranged on the cover plate 11 or the housing 12, and can be adaptively adjusted according to actual needs, and the utility model does not make specific limitations. For example, in some embodiments. Please refer to Fig. 9 and Fig.10In assembly production, the first pole 21 and the second pole 22 are both installed on the cover plate 11, the first pole 21 is welded to one end of the reference electrode 40 extending out of the battery cell assembly 30, and the second pole 22 is welded to the temperature detection component 60. The welding operation can be performed at the open end of the outer shell 12, or the first pole 21 and the reference electrode 40 with one end extending into the battery cell assembly 30 are welded, and the second pole 22 is welded to the temperature detection component 60, and then the pre-connected cover plate 11 and the battery cell assembly 30 and the pre-connected cover plate 11 and the temperature detection component 60 are placed in the outer shell 12.

[0063] Similar to the prior art, in some embodiments, the housing 10 may be provided with an explosion-proof valve 80 that releases pressure in response to pressure. When the pressure inside the battery cell 100 reaches a certain value, the explosion-proof valve 80 can connect the housing cavity of the housing 10 with the outside, thereby releasing pressure and improving the safety performance and reliability of the battery cell 100. The explosion-proof valve 80 may be any feasible structure in the prior art, which is not limited in this embodiment. For example, a notch groove may be formed on the housing 10 by an etching process.

[0064] In order to finally seal the accommodating cavity of the housing 10, the battery cell 100 further includes a plurality of seals for sealing the gap between two mutually matching components. For example, in some embodiments, one seal is used to seal the gap between the housing 12 and the cover plate 11, one seal is used to seal the gap between the first insulating member 51 and the housing 10, and if the first pole 21 is directly mounted on the housing 10, one seal is used to seal the gap between the first pole 21 and the housing 10.

[0065] In some embodiments, please refer to Figure 2 , Figure 4 and Figure 6 The positive output part 70 is arranged on the bottom wall opposite to the shell 12 and the cover plate 11. The cover plate 11 is the negative output part. The positive output part 70 is electrically connected to the positive pole ear 31. The cover plate 11 is electrically connected to the negative pole ear 32 and the current collecting plate. The first pole 21 is insulated and installed on the cover plate 11 through the first insulating member 51, and the second pole 22 is insulated and installed on the cover plate 11 through the second insulating member 52; the first insulating member 51 and the first pole 21 are integrally sealed and installed on the cover plate 11, and the second insulating member 52 and the second pole 22 are integrally sealed and installed on the cover plate 11. The insulation between the positive output part 70 and the cover plate 11 can be achieved by the insulation between the cover plate 11 and the shell 12, or by the insulation between the positive output part 70 and the shell 12.

[0066] In some embodiments, please refer to Figure 5 and Figure 6The structure of the positive output part 70 can also be an I-shaped structure to achieve fixed positioning of the positive output part 70 on the outer shell 12. The positive output part 70 can be processed into a T-shaped cylindrical structure. The positive output part 70 passes through the hole on the bottom wall of the outer shell 12, and the other end can be formed into a limiting edge by hot pressing, so that the positive output part 70 is finally formed into an I-shaped cylindrical structure on the bottom wall of the outer shell 12.

[0067] Based on the same inventive concept, the utility model also provides a battery, including at least one of the above-mentioned battery cells 100. Since the battery has the above-mentioned battery cells 100, it naturally has all the above-mentioned beneficial effects, and can detect the use status and failure status of each battery cell 100 in real time and non-destructively through the reference electrode 40, and can effectively reduce the influence of the reference electrode 40 on the local lithium ion transmission speed and the influence on the normal use of the battery cell 100, and the safety performance and comprehensive performance of the battery can be effectively improved.

[0068] When the battery cells 100 are assembled into a battery, two probes can be designed for each battery cell 100. One probe is connected to the first pole 21 to receive the electrode potential of the reference electrode 40 in real time for comparison with the negative electrode potential. The other probe is connected to the second pole 22 to receive the temperature change inside the battery in real time. When there are multiple battery cells 100, each battery cell 100 realizes signal transmission through the corresponding two probes.

[0069] It should be noted that the battery here can be a battery pack or other forms of batteries, and the present utility model does not limit this.

[0070] The battery cell 100 and the battery provided by the utility model have at least the following beneficial effects:

[0071] 1. By adopting the solution of building the reference electrode 40 and the temperature sensor in the battery cell 100, the use status of each battery cell 100 in the battery can be detected in real time and non-destructively. Compared with the reference electrode 40 of the traditional copper sheet and copper wire, the mesh reference electrode 40 with multiple evenly distributed vias 43 has a larger surface area, which can provide more electroplating sites for lithium, and is conducive to the uniform electroplating of lithium on the copper mesh.

[0072] 2. By arranging a first insulating member 51 with a low melting point between the cover plate 11 and the first pole 21, and arranging a second insulating member 52 with a low melting point between the cover plate 11 and the second pole 22, the first insulating member 51 can insulate the first pole 21 from the cover plate 11, and the second insulating member 52 can insulate the second pole 22 from the cover plate 11. In addition, when the battery cell 100 has thermal runaway and the temperature rises, the first insulating member 51 and the second insulating member 52 with a low melting point melt first, so that the pressure inside the battery cell 100 is released first from the first pole 21 and the second pole 22, thereby achieving the effect of internal pressure relief of the battery cell 100, which has the advantages of good safety, high reliability and simple structure.

[0073] 3. The battery cell 100 of this design can be adapted for battery assembly production, which optimizes the current situation where the battery cannot detect the internal failure state of the battery cell 100. It only needs to set two probes for each battery cell 100 on the battery to receive the electrical signals transmitted outward by the reference electrode 40 and the temperature detection component 60 one by one, so as to achieve the technical effect of real-time detection of the internal condition of each battery cell 100.

[0074] The above specific examples are used to illustrate the present invention, which are only used to help understand the present invention and are not intended to limit the present invention. For those skilled in the art of the present invention, some simple deductions, deformations or substitutions can be made based on the idea of ​​the present invention.

Claims

1. A battery cell, characterized in that: include: A housing having a receiving cavity; A first pole, mounted on the housing and used for external electrical connection of the battery cell; A battery cell assembly, packaged in the accommodating cavity of the shell; And a reference electrode, the reference electrode includes a main body and a handle, the two ends of the handle are respectively connected to the main body and the first pole; the main body and one end of the handle close to the main body are insulated and arranged in the battery cell assembly; the main body is sheet-shaped, and the main body is provided with at least one through hole penetrating along the ion movement direction of the battery cell assembly.

2. The battery cell according to claim 1, characterized in that: There are multiple via holes, and the multiple via holes are evenly distributed in the main body.

3. The battery cell according to claim 1, characterized in that: The cross section of the via hole is circular or square, and the diameter / side length of the via hole is 10 μm to 1000 μm.

4. The battery cell according to claim 1, characterized in that: The battery cell assembly includes a positive electrode sheet, a negative electrode sheet and a first separator disposed between the positive electrode sheet and the negative electrode sheet, and the battery cell also includes a second separator, and the second separator is disposed on a side of the first separator away from the positive electrode sheet or away from the negative electrode sheet; the main body is sandwiched between the first separator and the second separator; The outer surface of the portion of the handle extending outside the battery core assembly has an insulating layer, or the handle is an insulating handle made of insulating material.

5. The battery cell according to any one of claims 1 to 4, characterized in that: The shell has a first through hole communicating with the accommodating cavity; the battery cell further includes a first insulating member, the first insulating member is installed in the first through hole, and the melting point of the first insulating member is 80° C. to 120° C.

6. The battery cell according to claim 5, characterized in that: The housing further has a second through hole communicating with the accommodating cavity, the battery cell further comprises a second insulating member, a second pole and a temperature detecting member, the second insulating member is installed in the second through hole, the temperature detecting member is arranged in the accommodating cavity and is electrically connected to the second pole to monitor the temperature of the battery cell; One of the first insulating member and the second insulating member is sleeved on the outer circumference of the first pole, and the other is sleeved on the outer circumference of the second pole.

7. The battery cell according to claim 6, characterized in that: The melting point of the second insulating member is 80°C to 120°C.

8. The battery cell according to any one of claims 1 to 4, characterized in that: The shell comprises a cover plate and an outer shell with an opening, wherein the cover plate is connected to the open end of the outer shell; and the first pole is arranged on the cover plate.

9. The battery cell according to any one of claims 1 to 4, characterized in that: The shell is also provided with an explosion-proof valve for releasing pressure in response to pressure.

10. A battery, characterized in that: Comprising at least one battery cell according to any one of claims 1 to 9.

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