Electrochemical device and electronic device

Abstract

An electrochemical device, comprising a housing, an electrode assembly, a first tab, a second tab, an adapter piece and a terminal post, wherein the housing comprises a first wall body, a second wall body and a third wall body, the first wall body being electrically conductive and being disposed opposite the third wall body, the second wall body being connected to the first wall body and the third wall body so as to enclose an accommodating chamber together with the first wall body and the third wall body; the electrode assembly is disposed within the accommodating chamber, and the first wall body has a first opening so as to be in communication with the accommodating chamber; the terminal post seals the first opening and is electrically insulated from the first wall body; the adapter piece is located between the electrode assembly and the first wall body, and the adapter piece is fixed to the second wall body and is electrically connected to the first wall body; the first tab and the second tab have opposite polarities, are electrically connected to the electrode assembly, respectively, and extend from the electrode assembly towards one side of the first wall body; and the first tab is electrically connected to the adapter piece, and the second tab is electrically connected to the terminal post. The electrochemical device described above reduces assembly difficulty and improves the stability of electrical connection. Further disclosed is an electronic device comprising the electrochemical device.

Description

Electrochemical devices and electronic devices Technical Field

[0001] This application relates to the field of energy storage technology, and more particularly to an electrochemical device and an electronic device having the electrochemical device. Background Technology

[0002] Electrochemical devices (such as batteries) are widely used in electronic mobile devices, power tools, and electric vehicles. Traditional hard-shell batteries are assembled by first combining the terminals and the casing cover to form an assembly. The wound battery cell is then placed inside the rigid casing. One electrode tab (e.g., the negative electrode tab) of the cell is welded (e.g., laser welding) to the casing to achieve electrical connection. The other electrode tab is welded to the terminal of the casing. Finally, the cover is welded to the main body.

[0003] Summary of the Invention

[0004] However, the inventors discovered that since the terminal post and the cover of the casing are first assembled to form a component, after the two tabs of different polarities are subsequently welded to the cover and the terminal post respectively, the two tabs will have a certain angle. When the cover is then welded to the body, the operation is restricted and it is not conducive to the stability of the overall structural electrical connection, thus affecting the battery's service life.

[0005] Therefore, this application proposes an electrochemical device that helps reduce assembly difficulty and improves electrical connection stability.

[0006] Additionally, this application also provides an electronic device having the electrochemical device.

[0007] This application provides an electrochemical device, including a housing, an electrode assembly, a first tab, a second tab, an adapter plate, and an electrode post. The housing includes a first wall, a second wall, and a third wall. The first wall is conductive and disposed opposite to the third wall. The second wall connects the first and third walls to form a receiving cavity. The electrode assembly is located within the receiving cavity. The first wall has a first opening communicating with the receiving cavity. The electrode post seals the first opening and is electrically insulated from the first wall. The adapter plate is located between the electrode assembly and the first wall, and is fixed to the second wall and electrically connected to the first wall. The first tab and the second tab have opposite polarities and are electrically connected to the electrode assembly, extending from the side of the electrode assembly toward the first wall. The first tab is electrically connected to the adapter plate, and the second tab is electrically connected to the electrode post.

[0008] In this application, the first and second electrodes with opposite polarities extend from the side of the electrode assembly toward the first wall, i.e., the first and second electrodes extend from the same side of the electrode assembly. When the electrodes are subsequently welded to other components, their welding points are located on the same side of the electrode assembly, thereby improving space utilization and the thinning of the electrochemical device, which in turn improves the overall energy density of the electrochemical device. The first electrode is electrically connected to the first wall via an adapter plate, and the adapter plate is fixed to the second wall. This allows for fixing the shape of the first electrode and the adapter plate by first connecting the adapter plate to the first electrode and then fixing the adapter plate to the second wall. This reduces interference during subsequent electrical connections between the first wall and the adapter plate, and between the second electrode and the electrode post, improving the stability and convenience of electrical connections. Ultimately, this reduces assembly difficulty while extending the lifespan of the electrochemical device.

[0009] In some possible implementations, the first wall includes a recessed portion facing inward toward the receiving cavity, a first opening is disposed in the recessed portion, and the electrode post is fixed in the recessed portion and embedded in the first opening. By disposing the electrode post in the recessed portion, it is beneficial to reduce the overall thinness of the electrochemical device, increase the energy density of the electrochemical device, and also improve the overall flatness of the electrochemical device.

[0010] In some possible implementations, the adapter plate is annular with a second opening, into which a recessed portion is embedded. The annular shape of the adapter plate increases the contact area between it and the first wall, thereby improving the stability of the electrical connection between the adapter plate and the first wall, and consequently, the stability of the electrical connection between the first electrode and the first wall. Simultaneously, the annular shape also facilitates the fixation between the adapter plate and the second wall, improving the connection stability and the morphological stability of the first electrode. Furthermore, the recessed portion embedded in the second opening fully utilizes the internal space of the electrochemical device to accommodate the electrode post, further contributing to the overall thinning of the electrochemical device, increasing its energy density, and improving its overall flatness.

[0011] In some possible implementations, the recess and the adapter piece are snapped together through the second opening, which helps to improve the stability of the electrical connection between the adapter piece and the first wall, and also facilitates the electrical connection between the adapter piece and the first wall. When the recess and the second opening are snapped together, it is possible to electrically connect the adapter piece and the first wall without welding.

[0012] In some possible implementations, the first tab includes a first connecting portion, a first bent portion, and a first transition portion connected in sequence. The first connecting portion is electrically connected to the electrode assembly, and the first transition portion is bent towards the surface of the electrode assembly facing the first wall via the first bent portion, and is electrically connected to the transition piece. The fact that the first tab is bent before being electrically connected to the transition piece via the first transition portion increases the electrical connection area between the first tab and the transition piece, thereby improving the stability of the electrical connection in the electrochemical device.

[0013] In some possible implementations, the electrode assembly includes a first electrode, a second electrode, and a separator between the first and second electrodes. The electrode assembly is a wound structure wound around a central axis. A first connecting portion is electrically connected to the outermost or second outermost ring of the first electrode. A first adapter portion bends towards the central axis of the electrode assembly via a first bending portion. A second tab is electrically connected to the second electrode. Because the bending radius of the outermost or second outermost ring of the first electrode is large, the first connecting portion's electrical connection to the outermost or second outermost ring of the first electrode is beneficial to the stability of the electrical connection between the first electrode and the first tab, and helps reduce the risk of poor electrical connection caused by excessive bending of the first connecting portion with the first electrode. Furthermore, the first adapter portion's bending towards the central axis of the electrode assembly via the first bending portion increases the area of ​​the first adapter portion used for electrical connection with the adapter piece, thereby further improving the stability of the electrical connection between the first electrode and the adapter piece.

[0014] In some possible implementations, the second tab includes a second connecting portion, a second bending portion, and a second transition portion. The second connecting portion is electrically connected to the electrode assembly, and the second transition portion is bent towards the surface of the electrode assembly facing the first wall via the second bending portion, and is electrically connected to the electrode post. The fact that the second tab is bent before being electrically connected to the electrode post via the second transition portion increases the electrical connection area between the second tab and the electrode post, thereby improving the stability of the electrical connection in the electrochemical device.

[0015] In some possible implementations, the electrode assembly includes a first electrode, a second electrode, and a separator between the first and second electrodes. The electrode assembly is a wound structure wound around a central axis. A second connecting portion is electrically connected to the outermost or second outermost ring of the second electrode. A second transition portion bends towards the central axis of the electrode assembly via a second bending portion. A first tab is electrically connected to the first electrode. Because the bending radius of the outermost or second outermost ring of the second electrode is large, the electrical connection of the second connecting portion to the outermost or second outermost ring of the second electrode is beneficial to the stability of the electrical connection between the second electrode and the second tab, and helps reduce the risk of poor electrical connection caused by excessive bending of the second connecting portion. Furthermore, the bending of the second transition portion towards the central axis of the electrode assembly via the second bending portion increases the area of ​​the second transition portion for electrical connection with the electrode post, thereby further improving the stability of the electrical connection between the second electrode and the electrode post.

[0016] In some possible implementations, the second adapter is located on the side of the adapter plate facing the electrode assembly. The surface of the second adapter facing the adapter plate has a first region corresponding to the second opening and a second region other than the first region. The electrode assembly also includes a first insulating layer covering the second region. The second adapter, located on the side of the adapter plate facing the electrode assembly, allows the shape of the second electrode tab to be fixed when the adapter plate is fixed to the second wall, thereby improving the stability of the electrical connection between the second adapter and the electrode post. Furthermore, covering the second region with the first insulating layer reduces the risk of short circuit between the second electrode and the adapter plate, thus improving the safety and extending the lifespan of the electrochemical device.

[0017] In some possible implementations, the first insulating layer also extends to cover a portion of the first region, thereby further reducing the risk of short circuit between the second electrode and the adapter, and also reducing the risk of short circuit between the first region and the first wall, which in turn further improves the safety of the electrochemical device and extends its service life.

[0018] In some possible implementations, the electrochemical device further includes a second insulating layer disposed on the surface of the electrode assembly facing the first wall. The second insulating layer helps to reduce the risk of a short circuit when the adapter directly contacts the surface of the electrode assembly facing the first wall, and also helps to reduce the risk of a short circuit when the first wall directly contacts the surface of the electrode assembly facing the first wall. Furthermore, it helps to reduce the risk of a short circuit when the first tab and the second tab directly contact the surface of the electrode assembly facing the first wall, thereby further improving the safety of the electrochemical device and extending its service life.

[0019] In some possible implementations, the electrochemical device also includes an insulating seal located between the recess and the electrode post. This reduces the risk of a short circuit due to direct electrical connection between the electrode post and the recess, thereby further improving the safety and extending the service life of the electrochemical device. It also improves the sealing between the electrode post and the first wall, reducing the risk of substance leakage within the normally operating electrochemical device.

[0020] In some possible implementations, the electrode post includes a first portion and a second portion protruding from one side of the first portion along a first direction. The recess includes a bottom wall and a side wall connecting to the bottom wall. The first portion is located in the recess and spaced apart from the side wall of the recess. In a second direction perpendicular to the first direction, the width of the first portion is greater than the width of the first opening. The second portion extends into the first opening, and an insulating seal is located between the first portion and the bottom wall of the recess. Firstly, with the first portion located in the recess and the second portion extending into the first opening, when the pressure inside the electrochemical device, i.e., within the containment cavity, is excessive, this excessive pressure can act on the second portion to push the electrode post outward, causing the electrode post to loosen and create a gap between it and the first wall, or even completely separating the electrode post from the recess for pressure relief. This improves the safety of the electrochemical device without requiring a separate pressure relief valve. Secondly, the first part being located within the recessed portion helps reduce the height of the electrode post protruding from the side of the first wall away from the receiving cavity, or even prevents the electrode post from protruding from the side of the first wall away from the receiving cavity. This facilitates the overall thinning of the electrochemical device and increases its energy density. Furthermore, the separation of the first part from the sidewall of the recessed portion further reduces the risk of short circuits between the electrode post and the first wall. The width of the first part is greater than the width of the first opening, and the insulating seal is located between the first part and the bottom wall of the recessed portion, facilitating a seal between the electrode post and the first wall.

[0021] In some possible implementations, the insulating seal is annular and includes an inner periphery and an outer periphery. The projection of the outer periphery of the first part in a first direction is located between the outer periphery of the insulating seal and the inner periphery of the insulating seal. The projection of the inner periphery of the insulating seal in the first direction is located within the first opening. This is beneficial to further improve the insulation safety between the first part / electrode and the bottom wall / first wall, reduce the risk of short circuit, and thus further improve the safety of the electrochemical device.

[0022] In some possible implementations, the electrochemical device also includes an insulating protrusion that extends from the inner periphery of the insulating seal into the first opening, thereby further improving the insulation safety between the electrode and the first wall, reducing the risk of short circuits, and also improving the sealing performance between the electrode and the first wall, thus improving the overall safety and service life of the electrochemical device.

[0023] In some possible implementations, the thickness of the adapter piece is less than or equal to the depth of the recess, which facilitates contact and welding between the electrode post and the second electrode tab, and helps to improve the stability of the electrical connection in the electrochemical device.

[0024] In some possible implementations, the surface of the electrode post away from the electrode assembly does not extend beyond the surface of the first wall away from the electrode assembly, thereby further contributing to the overall thinning of the electrochemical device and improving the energy density of the electrochemical device.

[0025] In some possible implementations, the first tab is the negative tab, and the second tab is the positive tab. The adapter plate is made of stainless steel or nickel, the first wall is made of stainless steel or nickel, and the electrode post is made of aluminum or aluminum alloy, which is beneficial to the overall structural safety of the electrochemical device and to extending the service life of the electrochemical device.

[0026] In some possible implementations, the adapter piece is welded to the end face of the second wall away from the third wall, and the surface of the adapter piece away from the third wall is welded to the first wall, which helps to improve the stability of the adapter piece fixation and thus improve the stability of the electrical connection between the adapter piece and the first wall and the first electrode tab.

[0027] In some possible implementations, the electrochemical device is cylindrical, with a diameter not exceeding 3 cm. For small-sized cylindrical electrochemical devices, the above design significantly improves the overall energy density, stability and convenience of electrical connections, and assembly difficulty.

[0028] This application also provides an electronic device, including a main body and the aforementioned electrochemical device. The electronic device supplies power to the main body through the electrochemical device, and the electrochemical device has high reliability and long service life, thereby helping to extend the service life of the electronic device and reduce its operating costs. Attached Figure Description

[0029] Figure 1 is a schematic diagram of the structure of an electrochemical device provided in an embodiment of this application.

[0030] Figure 2 is an exploded view of an electrochemical device provided in an embodiment of this application.

[0031] Figure 3A is a cross-sectional view of an electrochemical device provided in an embodiment of this application along line III-III shown in Figure 1.

[0032] Figure 3B shows an enlarged view of point Q1 as shown in Figure 3A.

[0033] Figure 4 is an enlarged view of Q2 shown in Figure 3A.

[0034] Figure 5 is a cross-sectional view of an electrochemical device provided in an embodiment of this application along the VV shown in Figure 1.

[0035] Figure 6 is an enlarged view of the electrochemical device provided in another embodiment of this application at point Q2 shown in Figure 3A.

[0036] Figure 7 is a cross-sectional view of an electrochemical device provided in an embodiment of this application in the direction perpendicular to the winding center axis O.

[0037] Figure 8 is an exploded view of an electrochemical device provided in another embodiment of this application.

[0038] Figure 9 is a schematic diagram of the structure of an electronic device according to an embodiment of this application.

[0039] The following detailed description, in conjunction with the accompanying drawings, will further illustrate this application. Detailed Implementation

[0040] The technical solutions in the embodiments of this application are described clearly and in detail below. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Unless otherwise defined, 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 application belongs. The terminology used in the specification of this application is for the purpose of describing particular embodiments only and is not intended to limit this application.

[0041] The embodiments of this application will be described in detail below. However, this application may be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein. Rather, these exemplary embodiments are provided to provide a thorough and detailed understanding of this application to those skilled in the art.

[0042] Additionally, for brevity and clarity, the dimensions or thicknesses of various components and layers may be enlarged in the accompanying drawings. Throughout the text, the same numerical values ​​refer to the same elements. As used herein, the terms "and / or" and "and / or" include any and all combinations of one or more of the associated enumerated items. Furthermore, it should be understood that when element A is referred to as "connecting" element B, element A may be directly connected to element B, or there may be an intermediate element C and element A and element B may be indirectly connected to each other.

[0043] Furthermore, when describing the implementation of this application, the word "may" refers to "one or more implementations of this application".

[0044] The technical terms used herein are for the purpose of describing particular embodiments and are not intended to limit this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. It should be further understood that the term "comprising," as used in this specification, means the presence of the described features, values, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, values, steps, operations, elements, components, and / or combinations thereof.

[0045] Spatial terms, such as "above," may be used herein for convenience in describing the relationship between one element or feature and another element (or feature) or feature (or feature) illustrated in the figures. It should be understood that, in addition to the directions depicted in the figures, spatial terms are intended to include different orientations of the device or apparatus during use or operation. For example, if the device in the figure is flipped, an element described as "above" or "on" other elements or features would be oriented "below" or "under" other elements or features. Therefore, the exemplary term "above" can include both above and below orientations. It should be understood that although the terms first, second, third, etc., may be used herein to describe various elements, components, regions, layers, and / or portions, these elements, components, regions, layers, and / or portions should not be limited by these terms. These terms are used to distinguish one element, component, region, layer, or portion from another element, component, region, layer, or portion. Therefore, a first element, component, region, layer, or portion discussed below may be referred to as a second element, component, region, layer, or portion without departing from the teachings of the exemplary embodiments.

[0046] In this application, the design relationships of greater than, less than, or not equal to parameter values ​​need to exclude reasonable errors of the measuring equipment.

[0047] Please refer to Figures 1 and 2. One embodiment of this application provides an electrochemical device 100, including a housing 10, an electrode assembly 20, a first electrode tab 31, a second electrode tab 33, an adapter plate 40, and an electrode post 50. The electrode assembly 20, the first electrode tab 31, the second electrode tab 33, and the adapter plate 40 are housed within the housing 10.

[0048] In some embodiments, the housing 10 may be a rigid housing, and the housing 10 includes a conductive material, such as, but not limited to, aluminum, steel, etc. In some embodiments, specifically, the housing 10 may be a steel shell or an aluminum shell.

[0049] The housing 10 may include a first wall 11, a second wall 13, and a third wall 15. The first wall 11 is made of a conductive material, and the first wall 11 and the third wall 15 are disposed opposite each other. The second wall 13 connects the first wall 11 and the third wall 15 to cooperate with the first wall 11 and the third wall 15 to form a receiving cavity 10a. In some embodiments, the second wall 13 may be made of a non-conductive or conductive material; the third wall 15 may be made of a non-conductive or conductive material. In some embodiments, the second wall 13 and the third wall 15 may be an integral structure.

[0050] Please refer to Figures 2 and 3A. The first wall 11 has a first opening 11a, and the first opening 11a communicates with the receiving cavity 10a. The pole post 50 is inserted into the first opening 11a from the side of the first wall 11 away from the third wall 15, and the pole post 50 is electrically insulated from the first wall 11.

[0051] Referring to Figure 7, the electrode assembly 20 includes a first electrode 21, a second electrode 23, and a separator 25 disposed between the first electrode 21 and the second electrode 23. In some embodiments, the first electrode 21, the separator 25, and the second electrode 23 are stacked sequentially and can be wound around a winding center axis O along a winding direction D, so that the electrode assembly 20 has a wound structure wound around the winding center axis O. The separator 25 is used to prevent the first electrode 21 and the second electrode 23 from directly contacting each other, thereby preventing the electrode assembly 20 from short-circuiting. As shown in Figure 7, the winding center axis O is perpendicular to the paper surface, and the winding direction D is the direction of counterclockwise rotation around the winding center axis O as shown in Figure 7. In other embodiments, the winding direction D may also be the direction of clockwise rotation.

[0052] The electrode assembly 20 can be generally cylindrical (as shown in Figures 2 and 7), flat (not shown), or other regular or irregular shapes. Correspondingly, the housing 10 generally matches the shape of the electrode assembly 20. For example, as shown in Figures 1 and 2, when the electrode assembly 20 is generally cylindrical, the housing 10 is also generally cylindrical, and when the electrode assembly 20 is generally flat, the housing 10 is also generally flat. In this application, the flat electrode assembly is a common electrode assembly structure in the art, including a straight portion and bent portions connecting opposite ends of the straight portion. The following description will use the cylindrical shape of the electrode assembly 20 and the cylindrical shape of the housing 10 as examples.

[0053] The first tab 31 and the second tab 32 have opposite polarities, and the first tab 31 and the second tab 32 are electrically connected to the electrode assembly 20 and extend from the side of the electrode assembly 20 toward the first wall 11. Specifically, the first tab 31 is electrically connected to the first electrode plate 21, and the second tab 32 is electrically connected to the second electrode plate 23 and the pole post 50.

[0054] The adapter piece 40 is located between the electrode assembly 20 and the first wall 11, and is fixed to the second wall 13. The adapter piece 40 electrically connects the first electrode tab 31 to the first wall 11, thereby realizing the electrical connection between the first electrode 21 and the first wall 11. Specifically, in some embodiments, the adapter piece 40 may also be located between the first wall 11 and the second wall 12, that is, the adapter piece 40 may be welded to the end face of the second wall 12 facing away from the third wall 13, and the surface of the adapter piece 40 facing away from the third wall 13 may be welded to the first wall 11 (as shown in Figure 3B).

[0055] Both the first tab 31 and the second tab 32 extend from the electrode assembly 20 toward the first wall 11, such that the welding point of the first tab 31 to the adapter plate 40 and the welding point of the second tab 32 to the electrode post 50 are located on the same side of the electrode assembly 20. This is beneficial for improving space utilization and for making the electrochemical device thinner, thereby improving the overall energy density of the electrochemical device. During the assembly of the electrochemical device, the electrode post 50 is usually assembled with the first wall 11 to form a cover assembly first, then the first wall 11 and the first tab 31 are electrically connected, and the electrode post 50 and the second tab 32 are electrically connected before the cover assembly is fixed to the second wall. When the first tab 31 and the second tab 32 extend from the same side of the electrode assembly 20, the first tab 31 and the second tab 32 need to be arranged to avoid short circuits and affect subsequent welding. For example, the first connection point of the first tab 31 and the first electrode plate 21 and the second connection point of the second tab 32 and the second electrode plate 23 are respectively located on two lines passing through the winding central axis O and being approximately perpendicular to each other (that is, the first line passing through the first connection point and perpendicular to the winding central axis O and the second line passing through the second connection point and perpendicular to the winding central axis O are approximately perpendicular). As a result, when the first tab 31 is directly welded to the first wall 11 and the second tab 32 is directly welded to the pole post 50, the two affect each other and interfere, affecting the convenience of assembly, increasing the difficulty of assembly, and reducing the stability of electrical connection. This application introduces an adapter plate 40. By first connecting the adapter plate 40 to the first electrode tab 31 and then fixing the adapter plate 40 to the second wall 13, the shape of the first electrode tab 31 is fixed, and the adapter plate 40 is also fixed. This helps to reduce mutual interference between the first wall 11 and the adapter plate 40, and between the second electrode tab 32 and the electrode post 50, thus improving the stability and convenience of electrical connections. This, in turn, helps to reduce assembly difficulty and extend the service life of the electrochemical device. The effects of this design are particularly pronounced when the diameter of the cylindrical shell 10 does not exceed 3 cm.

[0056] Referring to Figures 3A and 4, the first wall 11 may include a recess 110 that is recessed toward the receiving cavity 10a, wherein a first opening 11a is provided in the recess 110. In this case, the electrode post 50 being disposed in the recess 110 is beneficial for the overall thinning of the electrochemical device, for increasing the energy density of the electrochemical device, and for improving the overall flatness of the electrochemical device. Specifically, the recess 110 may include a bottom wall 111 and a side wall 113 connecting the bottom wall 111, and the first opening 11a is provided in the bottom wall 111.

[0057] The electrochemical device 100 also includes an insulating seal 60, which is located between the electrode 50 and the recess 110, thereby achieving electrical insulation between the electrode 50 and the first wall 11. This helps reduce the risk of short circuit between the electrode 50 and the first wall 11. At the same time, the insulating seal 60 can also improve the sealing between the electrode 50 and the first wall 11, reducing the risk of leakage of substances in the electrochemical device during normal operation. Therefore, the installation of the insulating seal 60 helps to improve the safety of the electrochemical device and extend its service life.

[0058] The electrode post 50 may include a first portion 51 and a second portion 53, with the second portion 53 protruding from one side of the first portion 51 along a first direction X. The first portion 51 is located within the recess 110 and extends in a second direction Y perpendicular to the first direction X. The width of the first portion 51 is greater than the width of the first opening 11a. The second portion 53 extends into the first opening 11a. When the pressure inside the electrochemical device 100, i.e., the receiving cavity 10a, is excessive, this excessive pressure can act on the second portion 53 to push the electrode post 50 entirely outward, causing the electrode post 50 to loosen and create a gap between it and the first wall 11, or even completely separating the electrode post 50 from the recess 110 for pressure relief. This improves the safety of the electrochemical device 100 without the need for a separate pressure relief valve. Furthermore, the embedded design of the first portion 51 and the second portion 53 also contributes to the overall thinness of the electrochemical device and improves its energy density. The first part 51 is spaced apart from the side wall 113 of the recess 110. At this time, the insulating seal 60 is located between the first part 51 and the bottom wall 111 of the recess 110, which helps to further reduce the risk of short circuit between the pole 50 and the first wall 11. In addition, the fact that the width of the first part 51 is greater than the width of the first opening 11a also helps to improve the sealing performance of the insulating seal 60 between the pole 50 and the first wall 11. At the same time, when the pressure in the receiving cavity 10a is too high, the above-mentioned arrangement of the insulating seal 60 can facilitate the loosening and gap formation between the pole 50 and the first wall 11.

[0059] The insulating seal 60 is annular and includes an inner periphery 61 and an outer periphery 63. Further, the projection of the outer periphery 51a of the first portion 51 in the first direction X can be located between the inner periphery 61 and the outer periphery 63, and the projection of the inner periphery 61 in the first direction X can be located within the first opening 11a. This further enhances the insulation safety between the first wall 11 of the first portion 51, reduces the risk of short circuits, and thus further improves the safety of the electrochemical device.

[0060] In some embodiments, the surface of the electrode post 50 facing away from the electrode assembly 20 may not extend beyond the surface of the first wall 11 facing away from the electrode assembly 20. Specifically, the surface of the first portion 51 facing away from the electrode assembly 20 does not extend beyond the end of the side wall 113 facing away from the bottom wall 111, thereby further facilitating the overall thinning of the electrochemical device and improving the energy density of the electrochemical device.

[0061] In some embodiments, referring to FIG6, the electrochemical device 100 may further include an insulating protrusion 65, which extends from the inner periphery 61 of the insulating seal 60 into the first opening 11a, thereby further improving the insulation safety between the electrode 50 and the first wall 11, reducing the risk of short circuit, and also improving the sealing between the electrode 50 and the first wall 11, thereby improving the overall safety and service life of the electrochemical device.

[0062] The adapter piece 40 can be annular, for example, circular, as shown in Figures 2 to 5. In this case, the adapter piece 40 has a second opening 41, which corresponds to the recess 110. The annular adapter piece 40 helps to increase the contact area between the adapter piece 40 and the first wall 11, thereby improving the stability of the electrical connection between the adapter piece 40 and the first wall 11 and thus improving the stability of the electrical connection between the first electrode 31 and the first wall 11. At the same time, the annular adapter piece 40 also helps to fix the adapter piece 40 to the second wall 13, thereby improving the connection stability between the adapter piece 40 and the second wall 13, and also improving the stability of the shape of the first electrode 31. In some embodiments, the recess 110 can be further embedded in the second opening 41, thereby making full use of the internal space of the electrochemical device 100 to set the electrode post 50, which further helps to make the electrochemical device 100 thinner overall and improve the energy density of the electrochemical device 100, and also further helps to improve the overall flatness of the electrochemical device 100.

[0063] Furthermore, the recess 110 can also be engaged with the adapter piece 40 through the second opening 41, which helps to improve the stability of the electrical connection between the adapter piece 40 and the first wall 11, and also facilitates the electrical connection between the adapter piece 40 and the first wall 11. When the recess 110 is engaged with the second opening 41, it is possible to electrically connect the adapter piece 40 and the first wall 11 without welding.

[0064] In some embodiments, the first tab 31 can be a negative tab, the second tab 32 can be a positive tab, the adapter plate 40 can be made of stainless steel or nickel, the first wall 11 can be made of stainless steel or nickel, and the electrode post 50 can be made of aluminum or aluminum alloy. Since stainless steel and nickel are less prone to electrochemical corrosion when connected to the negative electrode, the aforementioned material selection for the adapter plate 40 and the first wall 11 helps reduce the risk of electrochemical corrosion. Overall, the above design helps extend the service life of the electrochemical device and improves its overall strength, thereby enhancing its safety. In other embodiments, the first tab 31 can also be a positive tab, and the second tab 32 can also be a negative tab. Correspondingly, the materials of the adapter plate 40, the first wall 11, and the electrode post 50 need to be adjusted accordingly. For example, the materials of the adapter plate 40 and the first wall 11 can both include aluminum or aluminum alloy, and the material of the electrode post 50 can include stainless steel or nickel.

[0065] Referring to Figures 2 to 5 and Figure 7, the first tab 31 may include a first connecting portion 311, a first bending portion 313, and a first adapter portion 315 connected in sequence. The first connecting portion 311 is electrically connected to the first electrode 21. The first adapter portion 315 is bent towards the surface of the electrode assembly 20 facing the first wall 11 via the first bending portion 313, and is electrically connected to the adapter piece 40. The first tab 31 is bent before being electrically connected to the adapter piece 40 via the first adapter portion 315, which increases the electrical connection area between the first tab 31 and the adapter piece 40, thereby improving the stability of the electrical connection in the electrochemical device.

[0066] Furthermore, the first connecting portion 311 can be electrically connected to the outermost or second outermost ring of the first electrode 21. Since the radius of curvature of the outermost or second outermost ring of the first electrode 21 is larger than that of the innermost ring closer to the winding center axis O, the first connecting portion 311 electrically connecting to the outermost or second outermost ring of the first electrode 21 is beneficial to the stability of the electrical connection between the first electrode 21 and the first tab 31, and helps to reduce the risk of poor electrical connection caused by excessive bending of the first connecting portion 311 with the first electrode 21. In this application, the outermost ring refers to the area of ​​the diaphragm, such as the first electrode 21, that wraps around the winding center axis O once from its end in a direction opposite to the winding direction D, and the second outermost ring refers to the area of ​​the outermost ring that wraps around the winding center axis O once from its beginning in a direction opposite to the winding direction D.

[0067] The first adapter portion 315 can be bent toward the winding center axis O by the first bending portion 313, which helps to increase the area of ​​the first adapter portion 315 for electrical connection with the adapter piece 40, and further helps to improve the stability of the electrical connection between the first electrode piece 21 and the adapter piece 40.

[0068] The second tab 32 may include a second connecting portion 321, a second bending portion 323, and a second transition portion 325 connected in sequence. The second connecting portion 321 is electrically connected to the second electrode 23. The second transition portion 325 is bent towards the surface of the electrode assembly 20 facing the first wall 11 via the second bending portion 323, and is electrically connected to the electrode post 50. The second tab 32 is bent before being electrically connected to the electrode post 50 via the second transition portion 325, which increases the electrical connection area between the second tab 32 and the electrode post 50, thereby improving the stability of the electrical connection in the electrochemical device.

[0069] Furthermore, the second connecting part 321 can be electrically connected to the outermost or second outermost ring of the second electrode 23. Since the radius of curvature of the outermost or second outermost ring of the second electrode 23 is larger than that of the inner ring closer to the winding center axis O, the electrical connection of the second connecting part 321 to the outermost or second outermost ring of the second electrode 23 is beneficial to the stability of the electrical connection between the second electrode 23 and the pole post 50, and helps to reduce the risk of poor electrical connection caused by excessive bending of the second connecting part 321 with the second electrode 23.

[0070] The second adapter 325 can be bent toward the winding center axis O by the second bending portion 323, which helps to increase the area of ​​the second adapter 325 for electrical connection with the pole post 50, thereby further improving the stability of the electrical connection between the second pole piece 23 and the pole post 50.

[0071] In some embodiments, the second adapter 325 may be located on the side of the adapter 40 facing the electrode assembly 20. In this case, when the adapter 40 is fixed to the second wall 13, the shape of the second tab 32 can be fixed by the adapter 40, which is beneficial to the stability of the electrical connection between the second adapter 325 and the pole post 50.

[0072] When the outermost or second outermost ring of the second electrode 23 is connected to the second connecting portion 321, the surface of the second transition portion 325 facing the transition piece 40 has a first region 325a corresponding to the second opening 41 and a second region 325b other than the first region 325a. The first region 325a is used for contact and electrical connection with the electrode post 50. It is understood that the second region 325b overlaps with the transition piece 40 in the first direction X. Therefore, in order to reduce the risk of short circuit between the second region 325b and the transition piece 40, the surface of the second region 325b facing the transition piece 40 may be covered with a first insulating layer 71 to improve the safety of the electrochemical device 100 and extend the service life of the electrochemical device 100. Furthermore, the first insulating layer 71 can extend to cover the first region 325a, which helps to further reduce the risk of short circuit between the second electrode 23 and the adapter 40, and also helps to reduce the risk of short circuit between the first region 325a and the first wall 11, thereby further improving the safety of the electrochemical device 100 and extending the service life of the electrochemical device 100.

[0073] In some embodiments, referring to FIG8, the electrochemical device 100 may further include a second insulating layer 73. The second insulating layer 72 is disposed on the surface of the electrode assembly 20 facing the first wall 11, covering the entire surface of the electrode assembly 20 facing the first wall 11. The provision of the second insulating layer 72 helps reduce the risk of a short circuit between the adapter 40 and the surface of the electrode assembly 20 facing the first wall 11, as well as the risk of a short circuit between the first wall 11 and the surface of the electrode assembly 20 facing the first wall 11. Furthermore, it helps reduce the risk of a short circuit between the first tab 31 and the second tab 32 and the surface of the electrode assembly 20 facing the first wall 11, thereby further improving the safety and extending the service life of the electrochemical device 100.

[0074] The electrochemical device 100 of any of the above embodiments can be applied to electronic devices. As shown in FIG9, the electronic device 200 also includes a body 201, and the electrochemical device 100 supplies power to the body 201.

[0075] Electronic devices 200 can be, but are not limited to, electric toys, electric vehicles, mobile phones, wearable devices, tablets, computers, drones, energy storage devices, etc.

[0076] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of this application without departing from the spirit and scope of the technical solutions of this application.

Claims

1. An electrochemical device, comprising a housing, an electrode assembly, a first tab, a second tab, an adapter plate, and an electrode post, wherein the housing includes a first wall, a second wall, and a third wall, the first wall being conductive and disposed opposite to the third wall, the second wall connecting the first wall and the third wall to form a receiving cavity with the first wall and the third wall, and the electrode assembly being located within the receiving cavity, wherein... The first wall has a first opening to communicate with the receiving cavity; The pole seals the first opening, and the pole is electrically insulated from the first wall. The adapter plate is located between the electrode assembly and the first wall, and the adapter plate is fixed to the second wall and electrically connected to the first wall; The first electrode and the second electrode have opposite polarities and are electrically connected to the electrode assembly respectively, extending from the side of the electrode assembly toward the first wall. The first electrode is electrically connected to the adapter piece, and the second electrode is electrically connected to the pole post.

2. The electrochemical device as described in claim 1, characterized in that, The first wall includes a recessed portion facing inward toward the receiving cavity, the first opening is provided in the recessed portion, and the pole is fixed in the recessed portion and embedded in the first opening.

3. The electrochemical device as described in claim 2, characterized in that, The adapter piece is annular and has a second opening, with the recessed portion embedded in the second opening.

4. The electrochemical device as described in claim 3, characterized in that, The recessed portion and the adapter piece are engaged through the second opening.

5. The electrochemical device according to any one of claims 2 to 4, characterized in that, The first electrode tab includes a first connecting portion, a first bending portion, and a first adapter portion connected in sequence. The first connecting portion is electrically connected to the electrode assembly. The first adapter portion is bent toward the surface of the electrode assembly facing the first wall through the first bending portion. The first adapter portion is electrically connected to the adapter piece.

6. The electrochemical device as described in claim 5, characterized in that, The electrode assembly includes a first electrode, a second electrode, and a separating membrane located between the first electrode and the second electrode. The electrode assembly is a wound structure wound around a central axis. The first connecting portion is electrically connected to the outermost or second outermost ring of the first electrode. The first transition portion bends toward the central axis of the winding of the electrode assembly through the first bending portion. The second electrode tab is electrically connected to the second electrode.

7. The electrochemical device according to any one of claims 2 to 5, characterized in that, The second electrode tab includes a second connecting portion, a second bending portion, and a second adapter portion. The second connecting portion is electrically connected to the electrode assembly. The second adapter portion is bent toward the surface of the electrode assembly facing the first wall through the second bending portion. The second adapter portion is electrically connected to the electrode post.

8. The electrochemical device as described in claim 7, characterized in that, The electrode assembly includes a first electrode, a second electrode, and a separator between the first electrode and the second electrode. The electrode assembly is a wound structure wound around a central axis. The second connecting portion is electrically connected to the outermost or second outermost ring of the second electrode. The second transition portion bends toward the central axis of the winding of the electrode assembly through the second bending portion. The first electrode tab is electrically connected to the first electrode.

9. The electrochemical device as described in claim 7 or 8, characterized in that, The second adapter is located on the side of the adapter plate facing the electrode assembly. The surface of the second adapter facing the adapter plate has a first region corresponding to the second opening and a second region other than the first region. The electrode assembly also includes a first insulating layer that covers the second region.

10. The electrochemical device as claimed in claim 9, characterized in that, The first insulating layer also extends to cover a portion of the first area.

11. The electrochemical device according to any one of claims 1 to 10, characterized in that, The electrochemical device further includes a second insulating layer disposed on the surface of the electrode assembly facing the first wall.

12. The electrochemical device according to any one of claims 2 to 11, characterized in that, The electrochemical device further includes an insulating seal located between the recess and the electrode post.

13. The electrochemical device as claimed in claim 12, characterized in that, The pole post includes a first portion and a second portion protruding from one side of the first portion along a first direction. The recess includes a bottom wall and a side wall connecting the bottom wall. The first portion is located in the recess and spaced apart from the side wall of the recess. In a second direction perpendicular to the first direction, the width of the first portion is greater than the width of the first opening. The second portion extends into the first opening. The insulating seal is located between the first portion and the bottom wall of the recess.

14. The electrochemical device as claimed in claim 13, characterized in that, The insulating seal is annular and includes an inner periphery and an outer periphery. The projection of the outer periphery of the first portion in the first direction is located between the outer periphery of the insulating seal and the inner periphery of the insulating seal. The projection of the inner periphery of the insulating seal in the first direction is located within the first opening.

15. The electrochemical device as claimed in claim 14, characterized in that, The electrochemical device further includes an insulating protrusion that extends from the inner periphery of the insulating seal into the first opening.

16. The electrochemical device according to any one of claims 2 to 9, characterized in that, The thickness of the adapter piece is less than or equal to the depth of the recess.

17. The electrochemical device according to any one of claims 1 to 16, characterized in that, The electrode post does not extend beyond the surface of the electrode assembly that is away from the first wall.

18. The electrochemical device according to any one of claims 1 to 17, characterized in that, The first electrode tab is a negative electrode tab, the second electrode tab is a positive electrode tab, the material of the adapter piece includes stainless steel or nickel, the material of the first wall body includes stainless steel or nickel, and the material of the electrode post includes aluminum or aluminum alloy.

19. The electrochemical device according to any one of claims 1 to 18, characterized in that, The adapter piece is welded to the end face of the second wall that is away from the third wall, and the surface of the adapter piece that is away from the third wall is welded to the first wall.

20. The electrochemical device according to any one of claims 1 to 19, characterized in that, The electrochemical device is cylindrical, and its diameter does not exceed 3 cm.

21. An electronic device comprising a body, wherein, The electronic device further includes an electrochemical device as described in any one of claims 1 to 20, the electrochemical device supplying power to the body.

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