WO2023050180A1

WO2023050180A1 - Electrochemical device and electrical apparatus

Info

Publication number: WO2023050180A1
Application number: PCT/CN2021/121784
Authority: WO
Inventors: 刘道林; 林森; 丁宇; 何平
Original assignee: 东莞新能源科技有限公司
Priority date: 2021-09-29
Filing date: 2021-09-29
Publication date: 2023-04-06
Also published as: CN115315846A

Abstract

Provided in the present application are an electrochemical device and an electrical apparatus. The electrochemical device comprises a packaging shell, a partition, a first electrode assembly and a second electrode assembly. A first packaging body of the packaging shell comprises a first main body portion and a first edge sealing portion, and a second packaging body of the packaging shell comprises a second main body portion and a second edge sealing portion. The first main body portion and the second main body portion are stacked in a first direction. The partition comprises a third main body portion between the first main body portion and the second main body portion, and a third edge sealing portion between the first edge sealing portion and the second edge sealing portion; and the third main body portion comprises a first edge connected to the third edge sealing portion. In the first direction, the distance t1 from the end of the first main body portion away from the third main body portion to the first edge is greater than the distance t2 from the end of the second main body portion away from the third main body portion to the first edge. The first edge sealing portion, the third edge sealing portion and the second edge sealing portion are bent towards the first main body portion, and have a relatively low risk of extending beyond the packaging shell.

Description

Electrochemical devices and electrical equipment

technical field

The present application relates to the technical field of energy storage, and in particular to an electrochemical device and electrical equipment.

Background technique

With the improvement of market demand, it is more and more urgent to increase the working voltage of lithium-ion batteries. An existing method to increase the working voltage of lithium-ion batteries is to package two bare cells in the same packaging case and connect them in series. However, when the packaging case is sealed and folded, there are bending edges. Exceeding the body of the package case, resulting in a higher risk of package failure when subjected to external impact.

application content

The purpose of this application is to provide an electrochemical device and electrical equipment to solve or at least partly solve the problem in the prior art that when the edge sealing of the packaging shell is folded, the folded edge exceeds the main body of the packaging shell, which will lead to packaging when receiving external impact. Issues with a high risk of failure.

According to one aspect of the present application, there is provided an electrochemical device including a packaging case, a separator, a first electrode assembly, and a second electrode assembly. The packaging shell includes a first package body and a second package body, the first package body includes a first main body part and a first edge sealing part, the second package body includes a second main body part and a second edge sealing part, the first main body part and The second main body parts are stacked and arranged along the first direction. The partition plate includes a third main body portion and a third edge sealing portion, the third main body portion is arranged between the first main body portion and the second main body portion along the first direction to define between the first main body portion and the second main body portion A first cavity and a second cavity separated from each other; the third edge sealing part is arranged between the first edge sealing part and the second edge sealing part, wherein the first edge sealing part, the third edge sealing part and the The second edge sealing portion is bent toward the first main body portion; the third main body portion includes a first edge connected to the third edge sealing portion. The first electrode assembly is arranged in the first cavity. The second electrode assembly is arranged in the second cavity. Along the first direction, the distance from the end of the first body part away from the third body part to the first edge is t1, and the distance from the end of the second body part away from the third body part to the first edge is t2, wherein t1 is greater than t2 . Compared with the situation in the prior art that the first packaging body and the second packaging body are arranged symmetrically with respect to the third main body, in the electrochemical device provided by this application, the first sealing part, the third sealing part and the second sealing part The risk of the bent edge protruding beyond the packaging shell after the edge portion is bent is low.

In an optional manner, the third main body part includes a first part and a second part, and the second part is recessed toward the first main body part to form a recess. The recess can increase the depth of the second cavity, so that the second electrode assembly disposed in the second cavity can be partially accommodated in the recess, thereby expanding the thickness of the second electrode assembly along the first direction.

In an optional manner, along the first direction, the first main body part, the second main body part and the concave part satisfy the following formula:

0<t3≤(t1-t2)/2

Wherein, t3 is the depth of the concave portion along the first direction. By reasonably setting the distance between the first main body, the second main body and the concave part, the different size requirements of the first electrode assembly in the first cavity and the second electrode assembly in the second cavity along the first direction can be met , and then the first electrode assembly and the second electrode assembly with similar design system, size and capacity can be used, and the overall consistency of the electrochemical device is better.

In an optional manner, along the first direction, t1 is not less than 2.5 mm, which can reduce the risk that the folded edges of the first edge sealing part, the third edge sealing part and the second edge sealing part exceed the packaging shell after bending .

In an optional manner, the first electrode assembly and the second electrode assembly are connected in series.

In an optional manner, the first edge sealing part, the third edge sealing part and the second edge sealing part jointly constitute the edge sealing part, and the edge sealing part includes a bent part, so as to extend on the first edge sealing part In the direction of the first main body part, the size of the electrochemical device becomes smaller; further, along the first direction, the height of the bent part is h, which satisfies: h≤t1, so as to ensure that the first edge sealing part and the third sealing part After the edge portion and the second edge sealing portion are bent, the folded edge does not exceed the packaging shell, thereby reducing the risk of package failure.

In an optional manner, the electrochemical device further includes a bonding member, and the bonding member is disposed between the first main body portion and the bending portion. Because the bent part is bonded to the first main body through the adhesive, the impact damage to the bent part by external force can be reduced, and the risk of warping and deformation of the bent part can be reduced, and the overall size of the electrochemical device is small.

In an optional manner, the bent part includes a first hem and a second hem, and the second hem is located between the first body part and the first hem, so that the first hem sealing part, the second hem are further reduced. The folded edges formed after the three edge-sealing parts and the second edge-sealing part are bent exceed the risk of the package shell, and can improve the reliability of the package.

In an optional manner, the bonding element is disposed between the first main body portion and the second hem. Since the second folded edge is bonded to the first main body through the bonding member, impact damage to the second folded edge by external force can be reduced, and the risk of warping and deformation of the second folded edge can be reduced, and the overall size of the electrochemical device is small.

In an optional manner, the separator includes an intermediate layer and an encapsulation layer located on a surface of the intermediate layer, and the encapsulation layer is located at least on the third edge sealing portion.

In an optional manner, the intermediate layer includes at least one of a metal material, a polymer material, or a carbon material, and the encapsulation layer includes a polymer material.

In an optional manner, the metal material includes Ni, Ti, Cu, Ag, Au, Pt, Fe, Co, Cr, W, Mo, Al, Mg, K, Na, Ca, Sr, Ba, Si, At least one of Ge, Sb, Pb, In, Zn, stainless steel (SUS), and combinations or alloys thereof.

In an optional manner, the above polymer materials include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyether ether ketone, polyimide Amine, polyamide, polyethylene glycol, polyamideimide, polycarbonate, cyclic polyolefin, polyphenylene sulfide, polyvinyl acetate, polytetrafluoroethylene, polymethylene naphthalene, polyylidene fluoride Ethylene, polyethylene naphthalate, polypropylene carbonate, poly(vinylidene fluoride-hexafluoropropylene), poly(vinylidene fluoride-co-chlorotrifluoroethylene), silicone, vinylon, poly Propylene, anhydride-modified polypropylene, polyethylene, ethylene and its copolymers, polyvinyl chloride, polystyrene, polyether nitrile, polyurethane, polyphenylene ether, polyester, polysulfone, amorphous α-olefin copolymer and at least one of its derivatives.

In an optional manner, the carbon material includes at least one of carbon felt, carbon film, carbon black, acetylene black, fullerene, conductive graphite film or graphene film.

In an optional manner, the first package further includes a first top seal, the second package further includes a second top seal, the partition further includes a third top seal, and the third top seal is arranged on Between the first top seal and the second top seal; the electrochemical device also includes a first tab, one end of the first tab is connected to the first electrode assembly, and the other end of the first tab is connected from the first top seal and the third top seal portion protrude from the packaging shell; the electrochemical device also includes a second tab, one end of the second tab is connected to the second electrode assembly, and the other end of the second tab is connected from the second top seal portion and The packaging shell protrudes between the third top sealing parts.

In an optional manner, the first top sealing part, the second top sealing part and the third top sealing part are arranged on the first side of the first main body part, and the first edge sealing part, the second edge sealing part and the second Three edge sealing parts are arranged on the third side of the first main body part, and the first side is opposite to the third side; and/or, the first edge sealing part, the second edge sealing part and the third edge sealing part are arranged on the first main body The second side of the portion, the first side being adjacent to the second side.

In an optional manner, the first top sealing part, the second top sealing part and the third top sealing part are arranged on the first side of the first main body part, and the first edge sealing part, the second edge sealing part and the second The three edge sealing parts are arranged on the second side of the first main body part, and the first side is adjacent to the second side. The first package also includes a first bottom seal, the second package also includes a second bottom seal, the partition further includes a third bottom seal, and the third bottom seal is arranged on the first bottom seal and the second bottom seal. Between the sealing parts, the first bottom sealing part, the second bottom sealing part and the third bottom sealing part are arranged on the third side of the first main body part, and the third side is opposite to the first side.

In an optional manner, the first bottom seal part, the third bottom seal part and the second bottom seal part are further bent toward the first main body part.

In an optional manner, the number of the first edge sealing part, the second edge sealing part and the third edge sealing part is more than two.

According to another aspect of the present application, an electrical device is provided, including the above-mentioned electrochemical device.

The beneficial effects of the present application include that, compared with the situation in the prior art where the first packaging body and the second packaging body are arranged symmetrically with respect to the third main body, the electrochemical device provided by the application reduces the number of the first sealing part, the second sealing part The risk that the folded edges of the third edge sealing part and the second edge sealing part exceed the packaging shell after bending.

Description of drawings

One or more embodiments are exemplified by the pictures in the corresponding drawings, and these exemplifications do not constitute a limitation to the embodiments. Elements with the same reference numerals in the drawings represent similar elements. Unless otherwise stated, the drawings in the drawings are not limited to scale.

FIG. 1 is a schematic diagram of an electrochemical device provided in Embodiment 1 of the present application;

Fig. 2 is a schematic diagram of a packaging case provided in Embodiment 1 of the present application;

Fig. 3 is a schematic diagram of an unpackaged and folded packaging shell provided in Embodiment 1 of the present application;

Fig. 4 is an exploded schematic view of the electrochemical device provided in Example 1 of the present application;

FIG. 5 is a schematic diagram of another implementation of the electrochemical device provided in Example 1 of the present application;

FIG. 6 is another schematic form of the electrochemical device in FIG. 1 in Embodiment 1 of the present application;

Fig. 7 is a schematic diagram of the relative arrangement of the first top seal part and the first edge seal part in the electrochemical device provided in Embodiment 1 of the present application;

Fig. 8 is a schematic diagram of the relative arrangement of the first top seal and the first bottom seal in the electrochemical device provided in Embodiment 1 of the present application;

Fig. 9 is a schematic diagram of the electrochemical device provided in Example 2 of the present application;

Fig. 10 is a schematic diagram of an electrochemical device provided in Embodiment 3 of the present application;

Fig. 11 is a schematic diagram of another electrochemical device provided in Embodiment 3 of the present application;

Fig. 12 is a schematic diagram of an electrical device provided by an embodiment of the present application.

Detailed ways

In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions in this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of this application Examples, not all examples. It should be understood that the specific embodiments described here are only used to explain the present application, not to limit the present application. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments in this application belong to the protection scope of this application.

It should be noted that when an element is said to be "fixed" to another element, it may be directly on the other element, or there may be one or more intervening elements therebetween. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or one or more intervening elements may be present therebetween. The terms "vertical", "horizontal", "left", "right" and similar expressions are used in this specification for the purpose of description only.

In addition, the technical features involved in the various embodiments of the present application described below may be combined with each other as long as they do not conflict with each other.

Embodiment one

FIG. 1 is a schematic diagram of an electrochemical device 100 provided in Embodiment 1 of the present application. The electrochemical device 100 includes a packaging case 1 , a separator 2 , a first electrode assembly 3 and a second electrode assembly 4 . The separator 2 is disposed in the packaging case 1 , and the first electrode assembly 3 and the second electrode assembly 4 are disposed in the packaging case 1 .

For the packaging case 1 mentioned above, please refer to FIG. 2 , the packaging case 1 includes a first packaging body 11 and a second packaging body 12 . The first packaging body 11 is used to accommodate the first electrode assembly 3 , and the second packaging body 12 is used to accommodate the second electrode assembly 4 .

The first packaging body 11 includes a first main body portion 111 and a first edge sealing portion 112, the second packaging body 12 includes a second main body portion 121 and a second edge sealing portion 122, and the first main body portion 111 and the second main body portion 121 are along the The first direction L1 is stacked. The first edge sealing portion 112 is formed by extending outward from the peripheral side of the first main body portion 111 . The second edge sealing portion 122 is formed by extending outward from the peripheral side of the second main body portion 121 .

The above-mentioned first direction L1 can be expressed as the thickness direction of the electrochemical device 100, the thickness direction of the electrochemical device 100 is perpendicular to the main plane of the first body part 111, or the thickness direction of the electrochemical device 100 is perpendicular to the second body part 121 main plane. Wherein, the main plane of the first main body portion 111 is the plane with the largest area in the first main body portion 111 . Wherein, the main plane of the second body part 121 is the plane with the largest area in the second body part 121 .

In the embodiment of the present application, for the convenience of expression, the first direction L1 is defined from the first main body part 111 to the second main body part 121, that is, the first direction L1 is from the center of the first main body part 111 to the center of the second main body part 121 . When the main plane of the first main body 111 is parallel to the main plane of the second main body 121 , the first direction L1 is from the main plane of the first main body 111 to the main plane of the second main body 121 .

It should be noted that the "first direction L1" is only set for convenience of expression.

In some embodiments, referring to FIG. 3 , the first packaging body 11 and the second packaging body 12 are integrally formed, and the first packaging body 11 and the second packaging body 12 can be folded along their connecting positions (dotted line in FIG. 3 ), so as to The first main body portion 111 and the second main body portion 121 are overlapped along the first direction L1, and the first edge sealing portion 112 and the second edge sealing portion 122 are overlapped.

In some embodiments, the first packaging body 11 and the second packaging body 12 are molded separately, and when the first packaging body 11 and the second packaging body 12 are assembled to form the packaging shell 1, the first main body part 111 and the second packaging body 111 The two main body parts 121 are stacked along the first direction L1, and the first edge sealing part 112 and the second edge sealing part 122 are overlapped.

For the above separator 2, please refer to FIG. 4, the separator 2 includes a third body part 21 and a third edge sealing part 22, and the third body part 21 is arranged on the first body part 111 and the second body part along the first direction L1. 121, the third sealing portion 22 is disposed between the first sealing portion 112 and the second sealing portion 122, thereby defining a first cavity 11s between the third main body portion 21 and the first main body portion 111 , and a second cavity 12s is defined between the third body portion 21 and the second body portion 121 . Wherein, the first cavity 11s is used for accommodating the first electrode assembly 3 , and the second cavity 12s is used for accommodating the second electrode assembly 4 .

In some embodiments, please refer to FIG. 5 , the separator 2 includes an intermediate layer 21 s and an encapsulation layer 22 s located on the surface of the intermediate layer 21 s, and the encapsulation layer 22 s is located at least on the third sealing portion 22 . That is, optionally, the encapsulation layer 22s only covers the third edge sealing portion 22, or, optionally, the encapsulation layer 22s covers the middle layer 21s of the third edge sealing portion 22, and partially covers the middle layer of the third main body portion 21 21s, or, optionally, the encapsulation layer 22s covers the middle layer 21s of the third edge sealing part 22 and the middle layer 21s of the third main body part 21, that is, the middle layer covering the entire separator.

In some embodiments, the intermediate layer 21s includes at least one of a metal material, a polymer material, or a carbon material, and the encapsulation layer 22s includes a polymer material.

Among them, the above-mentioned metal materials include Ni, Ti, Cu, Ag, Au, Pt, Fe, Co, Cr, W, Mo, Al, Mg, K, Na, Ca, Sr, Ba, Si, Ge, Sb, Pb, At least one of In, Zn, stainless steel (SUS), a combination or alloy thereof, and the like.

Among them, the above polymer materials include polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyether ether ketone, polyimide, polyamide, polyethylene Diol, polyamideimide, polycarbonate, cyclic polyolefin, polyphenylene sulfide, polyvinyl acetate, polytetrafluoroethylene, polymethylene naphthalene, polyvinylidene fluoride, polynaphthalene Ethyl ester, polypropylene carbonate, poly(vinylidene fluoride-hexafluoropropylene), poly(vinylidene fluoride-co-chlorotrifluoroethylene), silicone, vinylon, polypropylene, anhydride-modified polypropylene , polyethylene, ethylene and its copolymers, polyvinyl chloride, polystyrene, polyether nitrile, polyurethane, polyphenylene ether, polyester, polysulfone, amorphous α-olefin copolymer and its derivatives kind.

Wherein, the carbon material includes at least one of carbon felt, carbon film, carbon black, acetylene black, fullerene, conductive graphite film or graphene film.

Regarding the above packaging case 1 and partition 2 , please refer to FIG. 4 and FIG. 6 , it can be understood that the first cavity 11s is formed by the first body part 111 being recessed away from the third body part 21 . The second cavity 12s is formed by indenting the second body portion 121 in a direction away from the third body portion 21 . The third main body portion 21 includes a first edge 221 connected to the third edge sealing portion 22 .

Along the first direction L1, the distance from the end of the first main body 111 away from the third main body 21 to the first edge 221 is t1, and the distance from the end of the second main body 121 away from the third main body 21 to the first edge 221 is t1. t2, where t1 is greater than t2.

Wherein, the end of the first body part 111 away from the third body part 21 is the surface of the first body part 111 facing away from the third body part 21 .

Wherein, the distance from the end of the first main body 111 away from the third main body 21 to the first edge 221 is the distance from the end of the first main body 111 away from the third main body 21 to the central section c1 of the first edge 221 .

Wherein, the end of the second body part 121 away from the third body part 21 is the surface of the second body part 121 facing away from the third body part 21 .

Wherein, the distance from the end of the second main body 121 away from the third main body 21 to the first edge 221 is the distance from the end of the second main body 121 away from the third main body 21 to the central section c1 of the first edge 221 .

Wherein, t1 is greater than t2, which means that along the first direction L1, the maximum distance from the point on the surface of the first body part 111 facing away from the third body part 21 to the first edge 221 is greater than that of the second body part 121 facing away from the third body part 21. The maximum distance from a point on the surface of the third body part 21 to the first edge 221 .

Please refer to FIG. 6 , the above-mentioned first edge sealing part 112 , third edge sealing part 22 and second edge sealing part 122 are bent toward the first main body part 111 to form the first edge folding 10 . A folded edge 10 is the bent portion 120. In FIG. 6, the first folded edge 10 is the area in the dotted line frame. In addition, the dotted line frame in FIG. 100 components.

Since the distance from the end of the first body part 111 away from the third body part 21 to the first edge 221 is greater than the distance from the end of the second body part 121 away from the third body part 21 to the first edge 221, thus compared with the existing In the case where the first packaging body 11 and the second packaging body 12 are arranged symmetrically with respect to the third main body part 21 in the technology, the first sealing part 112, the third sealing part 22 and the second sealing part 122 after the bending of the first sealing part The risk of a flap 10 protruding beyond the packaging shell 1 is low.

It is worth noting that, in some embodiments, along the first direction L1, the distance t1 from the end of the first body part 111 away from the third body part 21 to the first edge 221 is not less than 2.5 millimeters, so that the first edge sealing part 112 1. The risk that the first edge 10 formed by bending the third edge sealing part 22 and the second edge sealing part 122 toward the first main body part 111 beyond the packaging shell 1 is reduced. In some embodiments, along the first direction L1, the height of the bent portion 120 is h, that is, the height of the first folded edge 10 is h, satisfying: h≦t1.

Wherein, the height of the bent portion 120, or the height h of the first folded edge 10 is taken along the first direction L1, from the end of the first folded edge 10 facing away from the second main body portion 121 to the central section c1 of the first edge 221. distance.

In some embodiments, referring to FIG. 6 , an adhesive member 5 is further provided between the first hem 10 and the first main body portion 111 , and the first hem 10 is bonded to the first main body portion 111 by the adhesive member 5 , so as to reduce the collision damage of the first folded edge 10 by the external force, and reduce the risk of warping and deformation of the first folded edge 10 , and the overall size of the electrochemical device 100 is small.

It is worth noting that, in some embodiments, please refer to FIG. 6 , the wall thickness of the first body part 111 and the wall thickness of the second body part 121 are the same, because the end of the first body part 111 away from the third body part 21 to The distance t1 of the first edge 221 is greater than the distance t2 from the end of the second body part 121 far away from the third body part 21 to the first edge 221, so as to set a band for the differentiation of the first electrode assembly 3 and the second electrode assembly 4 come possible.

For the above packaging shell 1 and partition 2, please refer to FIG. The top seal part 23 , the first top seal part 113 , the third top seal part 23 and the second top seal part 123 are stacked along the first direction L1 . The electrochemical device 100 also includes a first tab 6, one end of the first tab 6 is connected to the first electrode assembly 3, and along the second direction L2, the other end of the first tab 6 is separated from the first top sealing part 113 and the second The packaging shell 1 protrudes between the three top sealing parts 23 to connect with external electrical equipment. The electrochemical device 100 also includes a second tab 7, one end of the second tab 7 is connected to the second electrode assembly 4, and along the second direction L2, the other end of the second tab 7 is separated from the second top seal portion 123 and the second tab 7. The packaging shell 1 protrudes between the three top sealing parts 23 .

Wherein, the second direction L2 is perpendicular to the first direction L1.

Wherein, in some embodiments, the second direction L2 may also be referred to as the length direction of the electrochemical device 100 .

In some embodiments, please refer to FIG. 7 , the first top seal portion 113 and the first edge seal portion 112 are disposed on opposite sides of the first main body portion 111 along the second direction L2, and the second top seal portion 123 and the second The edge sealing portion 122 is disposed opposite to both sides of the second main body portion 121 along the second direction L2, and the third top sealing portion 23 and the third edge sealing portion 22 are disposed opposite to both sides of the third main body portion 21 along the second direction L2. side.

In other embodiments, please refer to FIG. 6 , the first edge sealing portion 112 is disposed on both sides of the first main body portion 111 along the third direction L3, and the second edge sealing portion 122 is disposed on the second body along the third direction L3. The third edge sealing portion 22 is disposed on both sides of the third main body portion 21 along the third direction L3.

Wherein, the third direction L3 is perpendicular to the first direction L1 and the second direction L2 respectively.

Wherein, in some embodiments, the third direction L3 may also be referred to as a width direction of the electrochemical device 100 .

It can be understood that there are at least two first tabs 6 , one of which is a positive tab, and the other first tab 6 is a negative tab.

It can be understood that there are at least two second tabs 7 , one of which is a positive tab, and the other second tab 7 is a negative tab.

It is worth noting that, please refer to FIG. 6 and FIG. 8 together. When the first edge sealing portion 112 is arranged on both sides of the first main body portion 111 along the third direction L3, the second edge sealing portion 122 is arranged along the third direction L3. On both sides of the second body part 121, the third edge sealing part 22 is arranged on both sides of the third body part 21 along the third direction L3, and the first packaging body 11 also includes a first bottom seal part 114, the first bottom seal part 114 and the first top seal part 113 are oppositely disposed on both sides of the first main body part 111 along the second direction L2, and the second package body 12 also includes a second bottom seal part 124, a second bottom seal part 124 and a second top seal part 124. The sealing part 123 is disposed opposite to the two sides of the second main body part 121 along the second direction L2. The separator 2 also includes a third bottom sealing part 24, and the third bottom sealing part 24 and the third top sealing part 23 are arranged along the second direction L2. They are oppositely disposed on two sides of the third main body portion 21 .

In some embodiments, the first bottom seal portion 114 , the third bottom seal portion 24 and the second bottom seal portion 124 are also bent toward the first main body portion 111 .

It is worth noting that, referring to FIG. 6 , when the first edge sealing portion 112 is arranged on both sides of the first main body portion 111 along the third direction L3, the second edge sealing portion 122 is arranged on the second main body portion along the third direction L3. 121, the third edge sealing part 22 is provided on both sides of the third main body part 21 along the third direction L3, the number of the first edge sealing part 112 is two, and the two first edge sealing parts 112 are arranged along the third The direction L3 is oppositely arranged on both sides of the first main body portion 111, the number of the second edge sealing portion 122 is two, and the two second edge sealing portions 122 are oppositely arranged on both sides of the second main body portion 121 along the third direction L3 , the number of the third edge sealing portion 22 is two, and the two third edge sealing portions 22 are disposed on opposite sides of the third main body portion 21 along the third direction L3.

For the above-mentioned first electrode assembly 3 , please refer to FIG. 4 , the first electrode assembly 3 is disposed in the first cavity 11 s, and the first electrode assembly 3 is used to supply power to external electrical equipment. The external power supply can also charge the first electrode assembly 3 .

For the above-mentioned second electrode assembly 4 , please refer to FIG. 4 , the second electrode assembly 4 is disposed in the second cavity 12 s, and the second electrode assembly 4 is used to supply power to external electrical equipment. The external power source can also charge the second electrode assembly 4 .

In some embodiments, the first electrode assembly 3 and the second electrode assembly 4 are connected in series, and are used to supply power to external electrical equipment.

For the above-mentioned first electrode assembly 3 and second electrode assembly 4, please refer to FIG. 6, from the above, since along the first direction L1, the depth h1 of the first cavity 11s is greater than the depth h2 of the second cavity 12s, then along the In the first direction L1, the thickness of the first electrode assembly 3 disposed in the first cavity 11s is greater than the thickness of the second electrode assembly 4 disposed in the second cavity 12s. In some embodiments, the first electrode assembly 3 The capacity is consistent with the capacity of the second electrode assembly 4.

In the present application, along the first direction L1, the distance from the end of the first body part 111 away from the third body part 21 to the first edge 221 is t1, and the distance from the end of the second body part 121 away from the third body part 21 to the first edge 221 is t1. The distance between the edge 221 is t2, wherein t1 is greater than t2, therefore, the risk of the first edge sealing part 112, the third edge sealing part 22 and the second edge sealing part 122 protruding beyond the packaging shell 1 is reduced.

Embodiment two

FIG. 9 is a schematic diagram of an electrochemical device 100 provided in Embodiment 2 of the present application. The difference between the second embodiment and the first embodiment is that the first edge sealing part 112 , the third edge sealing part 22 and the second edge sealing part 122 are bent toward the first main body part 111 to form the first hem 10 , and the first hem sealing 10 is bent toward the first main body portion 111 to form a second folded edge 20 , and the second folded edge 20 is located between the first main body portion 111 and the first folded edge 10 . That is, the first edge sealing part 112 , the third edge sealing part 22 and the second edge sealing part 122 are bent once to form the first edge folding 10 , and the first edge sealing 10 is bent again to form the second edge folding 20 . In the second embodiment of the present application, the bent portion 120 includes the first folded edge 10 and the second folded edge 20 . The areas in the two dotted boxes in FIG. 9 illustrate the first hem 10 and the second hem 20 respectively. The two dotted boxes in FIG. 9 are only set for the convenience of expressing the text of this application, and it does not mean that the electrochemical device 100 of this application includes these two dotted boxes.

In some embodiments, a bonding member 5 is provided between the second folded edge 20 and the first main body portion 111, and the second folded edge 20 is bonded to the first main body portion 111 through the sealing member 5, thereby reducing the impact of external force on the first main body portion 111. The collision damage of the second folded edge 20 can reduce the risk of warping and deformation of the second folded edge 20 , and the overall size of the electrochemical device 100 is small.

It is worth noting that other technologies in the first embodiment can also be combined with the second embodiment, and the technical solutions formed by them are also within the protection scope of the present application.

In the embodiment of the present application, the first edge sealing part 112 , the third edge sealing part 22 and the second edge sealing part 122 are bent toward the first main body part 111 to form the first hem 10 and then face the first main body part 111 again. The bending forms the second edge 20 , thereby further reducing the risk that the edge formed by bending the first edge sealing part 112 , the third edge sealing part 22 and the second edge sealing part 122 exceeds the packaging shell 1 .

Embodiment three

FIG. 10 is a schematic diagram of an electrochemical device 100 provided in Embodiment 3 of the present application. The third embodiment differs from the first embodiment in that the third main body 21 of the separator 2 includes a first part 211 and a second part 212 , and the second part 212 is recessed toward the first main body 111 to form a recess 2 s. The distance from the end of the first main body 111 away from the first portion 211 to the first edge 221 is t1, and the distance from the end of the second main body 121 away from the first portion 211 to the first edge 221 is t2. Wherein, t1 is greater than t2.

Wherein, the end of the first body portion 111 away from the first portion 211 is the surface of the first body portion 111 facing away from the first portion 211 .

Wherein, the end of the second body part 121 away from the first part 211 is the surface of the second body part 121 facing away from the first part 211 .

Wherein, t1 is greater than t2, which means that along the first direction L1, the maximum distance from the point on the surface of the first main body 111 facing away from the first part 211 to the first edge 221 is greater than that of the second main body 121 facing away from the first part. The maximum distance from a point on the surface of 211 to the first edge 221.

It is worth noting that, in some embodiments, along the first direction L1, the following formula is satisfied:

0<t3≤(t1-t2)/2

Wherein, t3 is the depth of the recess 2s along the first direction L1, that is, the distance from the end of the second portion 212 close to the second main body 121 to the central section c1 of the first edge 221 along the first direction L1.

Wherein, an end of the second portion 212 close to the second main body 121 is a surface of the second portion 212 facing the second main body 121 .

In other embodiments, the first cavity 11s, the second cavity 12s and the recess 2s satisfy the following formula:

Among them, 0.4mm is the tolerance.

The above-mentioned concave portion 2s serves as a part of the second cavity 12s, and the second electrode assembly 4 provided in the second cavity 12s can be partially accommodated in the concave portion 2s. When t1-t3=t2+t3, that is, the depth of the first cavity 11s ( When t1-t3) is equal to the depth (t2+t3) of the second cavity 12s, the thicknesses of the first electrode assembly 3 and the second electrode assembly 4 along the first direction L1 can be set to be similar, so that the first electrode The assembly 3 and the second electrode assembly 4 have similar design systems, design dimensions and capacities, so the overall consistency of the electrochemical device 100 is better.

It should be noted that, in some embodiments, the first part 211 is disposed on the peripheral side of the second part 212 .

It is worth noting that the third embodiment can also be combined with the above second embodiment, and the technical solution formed by it is also within the protection scope of the present application.

The electrochemical device 100 formed in combination of Embodiment 3 and Embodiment 2 can be referred to FIG. 11 . The difference between FIG. 11 and the electrochemical device 100 provided in Embodiment 1 is that the third main body 21 of the separator 2 includes the above-mentioned first part 211 and the second part 212, the first hem 10 formed by bending the first hem portion 112, the third hem portion 22 and the second hem portion 122 toward the first main body portion 111 is bent toward the first main body portion 111 Second hem 20.

In the embodiment of the present application, the third main body portion 21 of the separator 2 includes a first portion 211 and a second portion 212, and the second portion 212 is recessed toward the first main body portion 111 to form a recess 2s. The concave portion 2s serves as a part of the second cavity 12s, so that the second electrode assembly 4 disposed in the second cavity 12s can be partially accommodated in the concave portion 2s, thereby expanding the thickness of the second electrode assembly 4 along the first direction L1, and further By reasonably setting the depths of the first cavity 11s, the second cavity 12s and the recess 2s, the first electrode assembly 3 in the first cavity 11s and the second electrode assembly 4 in the second cavity 12s can be set have the same thickness along the first direction L1, and then the first electrode assembly 3 and the second electrode assembly 4 with similar design system, arrangement size and capacity can be used, and the overall consistency of the electrochemical device 100 is better.

Embodiment Four

Embodiment 4 provides an example of an electric device 200 , please refer to FIG. 12 , the electric device 200 includes a load 201 and any electrochemical device 100 in Embodiment 1, Embodiment 2 and Embodiment 3. The electrochemical device 100 is connected to a load 201 , and the electrochemical device 100 is used to supply power to the load 201 .

The electric device 200 may be an energy storage product, a mobile phone, a tablet, a drone, an electric vehicle with one wheel or more than two wheels, or an electric cleaning tool.

For example, for the above-mentioned unmanned aerial vehicle, the battery pack is carried on the unmanned aerial vehicle, and the battery pack is used to supply power to the loads on the unmanned aerial vehicle including the flight system, control system and camera system.

It should be noted that preferred embodiments of the application are given in the specification and accompanying drawings of the application, but the application can be implemented in many different forms, and are not limited to the embodiments described in the specification. These embodiments are not intended as additional limitations on the content of the present application, and the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive. Moreover, the above-mentioned technical features continue to be combined with each other to form various embodiments not listed above, which are all regarded as the scope of the description of the present application; furthermore, for those of ordinary skill in the art, improvements or changes can be made according to the above description , and all these improvements and transformations should belong to the scope of protection of the appended claims of this application.

Claims

An electrochemical device, characterized in that, comprising:

The packaging shell includes a first package body and a second package body, the first package body includes a first main body part and a first edge sealing part, and the second package body includes a second main body part and a second edge sealing part, The first main body part and the second main body part are arranged stacked along the first direction;

The separator includes a third main body part and a third edge sealing part, the third main body part is arranged between the first main body part and the second main body part along the first direction, so that A first body portion and the second body portion define a first cavity and a second cavity spaced apart from each other; the third edge sealing portion is disposed on the first edge sealing portion and the second edge sealing portion Between, wherein, the first edge sealing part, the third edge sealing part and the second edge sealing part are bent toward the first main body part; the third main body part includes the third edge sealing part abutting first edges;

a first electrode assembly disposed in the first cavity;

a second electrode assembly disposed in the second cavity;

Along the first direction, the distance from the end of the first main body away from the third main body to the first edge is t1, and the distance from the end of the second main body far away from the third main body to the first edge is t1. The distance of the first edge is t2, wherein t1 is greater than t2.
The electrochemical device according to claim 1, wherein the third body part includes a first part and a second part, and the second part is recessed toward the first body part to form a recess.
The electrochemical device according to claim 2, characterized in that, along the first direction, the first main body, the second main body and the recess satisfy the following formula:

0<t3≤(t1-t2)/2

Wherein, the t3 is the depth of the concave portion along the first direction.
The electrochemical device according to claim 1, wherein at least one of the following conditions is satisfied:

(1) Along the first direction, the t1 is not less than 2.5 mm;

(2) The first electrode assembly and the second electrode assembly are connected in series.
The electrochemical device according to claim 1, wherein the first sealing part, the third sealing part and the second sealing part jointly constitute a sealing part, and the sealing part comprises a bent part; Along the first direction, the height of the bent portion is h, which satisfies: h≦t1.
The electrochemical device according to claim 5, wherein at least one of the following conditions is satisfied:

(i) the bent portion includes a first folded edge and a second folded edge, and the second folded edge is located between the first main body portion and the first folded edge;

(ii) The electrochemical device further includes an adhesive member disposed between the first main body portion and the bent portion.
The electrochemical device according to claim 1, wherein the separator comprises an intermediate layer and an encapsulation layer located on the surface of the intermediate layer, and satisfies at least one of the following conditions:

(a) the encapsulation layer is located at least on the third edge sealing portion;

(b) The intermediate layer includes at least one of a metal material, a polymer material, or a carbon material, and the encapsulation layer includes a polymer material.
The electrochemical device according to claim 1, wherein the first package further comprises a first top seal, the second package further comprises a second top seal, and the separator further comprises a first top seal. Three top seal parts, the third top seal part is arranged between the first top seal part and the second top seal part; the electrochemical device also includes a first tab, and the first tab One end of the first tab is connected to the first electrode assembly, and the other end of the first tab protrudes from the packaging shell between the first top seal part and the third top seal part; the electrochemical device It also includes a second tab, one end of the second tab is connected to the second electrode assembly, and the other end of the second tab is connected between the second top seal and the third top seal. protrude from the packaging shell.
The electrochemical device according to claim 8, wherein the first top seal part, the second top seal part and the third top seal part are arranged on the first side of the first main body part and satisfy the following conditions At least one of:

(c) the first edge sealing part, the second edge sealing part and the third edge sealing part are arranged on a third side of the first main body part, and the first side is opposite to the third side;

(d) The first edge sealing part, the second edge sealing part and the third edge sealing part are arranged on the second side of the first main body part, and the first side is adjacent to the second side.
An electrical device, characterized by comprising the electrochemical device according to any one of claims 1-9.