CN216288852U

CN216288852U - Electrochemical device and electric equipment

Info

Publication number: CN216288852U
Application number: CN202122628854.2U
Authority: CN
Inventors: 苏士伟; 邓道林; 杨兴富; 陈文�
Original assignee: Ningde Amperex Technology Ltd
Current assignee: Ningde Amperex Technology Ltd
Priority date: 2021-10-29
Filing date: 2021-10-29
Publication date: 2022-04-12
Anticipated expiration: 2031-10-29

Abstract

The application relates to the technical field of energy storage, and particularly discloses an electrochemical device and electric equipment comprising the same. The shell comprises a top wall, a side wall and a bottom wall, and the top wall is provided with a first electrode. The electrode assembly includes a first pole piece and a second pole piece. The first pole piece and the first electrode are connected through the first pole lug, and the first electrode is connected through the first connecting piece. The second pole lug is connected with the second pole piece and the shell, and the second connecting piece is connected with the shell. When the electrochemical device is in a charging/discharging state, the magnetic field generated by the first lug and the magnetic field generated by the first connecting piece can be at least partially offset, and the magnetic field generated by the second lug and the magnetic field generated by the second connecting piece can be at least partially offset, so that the magnetic field generated by the electrochemical device is weakened, and the electromagnetic interference of the electrochemical device on electric equipment is reduced.

Description

Electrochemical device and electric equipment

Technical Field

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

Background

Button cell wide application is in bluetooth headset, and button cell influences user experience because of the noise at the bottom of the self magnetic field production can be to bluetooth headset's audio production influence.

SUMMERY OF THE UTILITY MODEL

In view of the above, it is desirable to provide an electrochemical device to reduce electromagnetic interference to electrical equipment.

In a first aspect of the present application, an electrochemical device is provided that includes a case and an electrode assembly housed in the case. The shell comprises a top wall, a side wall and a bottom wall, and the top wall is provided with a first electrode. The electrode assembly includes a first pole piece and a second pole piece. The electrochemical device satisfies at least one of the following conditions (i) to (ii): (i) the electrochemical device further comprises a first tab and a first connecting member disposed outside the housing. The first tab is connected with the first pole piece and the first electrode, and the first tab comprises a first connecting area connected with the first pole piece. The first connecting piece is connected with the first electrode. Viewed in a direction perpendicular to the top wall, a connecting line between the geometric center of the first connection region and the geometric center of the first electrode is a first reference line, the geometric center of the first electrode is taken as a circle center, a line length L1 between the geometric center of the first connection region and the geometric center of the first electrode is taken as a radius, sector areas of +/-45 degrees on two sides of the first reference line are first areas, the area of the first connecting piece is S1, and the area of an overlapping part of the first connecting piece and the first areas is S2, so that the requirements that: S2/S1 is more than or equal to 50 percent. (ii) The electrochemical device also includes a second tab and a second connecting member disposed outside the housing. The second pole lug is connected with the second pole piece and the shell, and the second pole lug comprises a second connecting area connected with the second pole piece and a third connecting area connected with the shell. The second connecting piece is connected with the shell. Viewed in a direction perpendicular to the bottom wall, a connecting line between the geometric center of the second connecting area and the geometric center of the third connecting area is a second reference line, the geometric center of the third connecting area is taken as a circle center, a line segment length L2 between the geometric center of the second connecting area and the geometric center of the third connecting area is taken as a radius, fan-shaped areas of +/-45 degrees on both sides of the second reference line are second areas, the area of the second connecting piece is S3, and the area of an overlapping portion of the second connecting piece and the second areas is S4, so that the following requirements are met: S4/S3 is more than or equal to 50 percent. When the electrochemical device is in a charging/discharging state, the magnetic field generated by the first pole lug and the magnetic field generated by the first connecting piece can be at least partially offset, and/or the magnetic field generated by the second pole lug and the magnetic field generated by the second connecting piece can be at least partially offset, so that the magnetic field generated by the end face of the electrochemical device is weakened. Compared with other values of S2/S1 and/or S4/S3, when the ratio of S2/S1 is more than or equal to 50% and/or the ratio of S4/S3 is more than or equal to 50%, the magnetic field on the end face of the electrochemical device is weaker, and the electromagnetic interference on electric equipment is smaller.

In some embodiments of the present application, the electrochemical device further satisfies at least one of the following conditions (iii) to (iv): (iii) S2/S1 is more than or equal to 70 percent; (iv) S4/S3 is more than or equal to 70 percent. When the ratio S2/S1 is more than or equal to 70 percent and/or the ratio S4/S3 is more than or equal to 70 percent, the magnetic field generated by the end face of the electrochemical device is smaller, and the difference of the magnetic field intensity at each part of the end face is smaller.

In some embodiments of the present application, the electrochemical device further satisfies at least one of the following conditions (v) to (vi): (v) a fourth connecting area is arranged at the end part of the first connecting piece far away from the first electrode; viewed in a direction perpendicular to the top wall, an angle between a connecting line between the geometric center of the fourth connecting region and the geometric center of the first electrode and a connecting line between the geometric center of the first connecting region and the geometric center of the first electrode is θ, and satisfies: theta is more than or equal to 0 degree and less than or equal to 45 degrees. (vi) A fifth connecting area is arranged at the end part, far away from the third connecting area, of the second connecting piece; viewed in a direction perpendicular to the bottom wall, an angle β between a line connecting the geometric center of the fifth connecting area and the geometric center of the third connecting area and a line connecting the geometric center of the second connecting area and the geometric center of the third connecting area satisfies: beta is more than or equal to 0 degree and less than or equal to 45 degrees.

Compared with the condition that theta is larger than 45 degrees, when theta is smaller than or equal to 45 degrees, the effect of mutual offset of the magnetic field generated by the first pole lug and the magnetic field generated by the first connecting piece is good, and the electromagnetic property of the electrochemical device is good. Compared with beta larger than 45 degrees, when the beta is smaller than or equal to 45 degrees, the effect of mutual offset of the magnetic field generated by the second pole lug and the magnetic field generated by the second connecting piece is better, and the electromagnetic property of the electrochemical device is better.

In some embodiments of the present application, an end of the first connection member remote from the first electrode is provided with a fourth connection region. Viewed in a direction perpendicular to the top wall, a connecting line between a geometric center of the fourth connecting area and a geometric center of the first electrode is a third reference line, the geometric center of the first electrode is taken as a center of a circle, a line length L3 between the geometric center of the fourth connecting area and the geometric center of the first electrode is taken as a radius, fan-shaped areas of ± 45 ° on both sides of the third reference line are third areas, and an area of an overlapping portion of the second connecting piece and the third areas is S5, so that the following requirements are met: S5/S3 is more than or equal to 50 percent. When the electrochemical device is in a charging/discharging state, the magnetic field generated by the first connecting piece and the magnetic field generated by the second connecting piece can be at least partially offset, so that the magnetic field generated by the whole electrochemical device is weakened. Compared with the case that S5/S3 is less than 50%, when S5/S3 is more than or equal to 50%, the effect that the magnetic field generated by the first connecting piece and the magnetic field generated by the second connecting piece are mutually counteracted is better, and the electromagnetic property of the electrochemical device is better.

In some embodiments of the present application, the ratio of area S5 to area S3 satisfies: S5/S3 is more than or equal to 85 percent. When the ratio of S5/S3 is more than or equal to 85 percent, the effect of mutual offset of the magnetic field generated by the first connecting piece and the magnetic field generated by the second connecting piece is better, and the difference of the magnetic field intensity at each position of the end face is smaller.

In some embodiments of the present application, an angle α between the first reference line and the second reference line, viewed in a direction perpendicular to the top wall, satisfies: alpha is more than or equal to 0 degree and less than or equal to 60 degrees. Compared with the alpha larger than 60 degrees, when the alpha is larger than or equal to 0 degrees and smaller than or equal to 60 degrees, the effect of mutual offset of the magnetic field generated by the first lug and the magnetic field generated by the second lug is better, and the magnetic field generated by the whole electrochemical device is smaller.

In some embodiments of the present application, the electrode assembly is in a wound structure. The first pole piece comprises a first active material layer, the first active material layer comprises a first end portion, and the first end portion is arranged at the winding starting end of the winding structure. The second pole piece comprises a second active material layer, the second active material layer comprises a second end portion, and the second end portion is arranged at the winding starting end of the winding structure. The distance between the geometric center of the first connection area and the first end along the length direction of the first pole piece is D1; the distance between the geometric center of the second connection region and the second end portion in the length direction of the second pole piece is D2, satisfying: D1/D2 is more than or equal to 0.5 and less than or equal to 2. Compared with other values of D1/D2, when D1/D2 is not less than 0.5 and not more than 2, the effect of mutual cancellation of the magnetic field generated by the first pole piece and the magnetic field generated by the second pole piece is better, and the influence of the magnetic field generated by the electrochemical device on the electric equipment is smaller. Furthermore, D1/D2 is more than or equal to 0.9 and less than or equal to 1.1, at the moment, the effect of mutual cancellation of the magnetic field generated by the first pole piece and the magnetic field generated by the second pole piece is better, and the difference of the magnetic field intensity at each position of the end face of the electrochemical device is smaller.

In some embodiments of the present application, the electrochemical device further satisfies at least one of the following conditions (a) to (b): (a) a fourth connecting area is arranged at the end part of the first connecting piece far away from the first electrode; a line segment length between the geometric center of the fourth connection region and the geometric center of the first electrode, as viewed in a direction perpendicular to the top wall, is L3, satisfying: L1/L3 is more than or equal to 0.5 and less than or equal to 2. (b) A fifth connecting area is arranged at the end part, far away from the third connecting area, of the second connecting piece; a line segment length between the geometric center of the fifth joining zone and the geometric center of the third joining zone, as viewed in a direction perpendicular to the bottom wall, is L4, satisfying: L2/L4 is more than or equal to 0.5 and less than or equal to 2.

Compared with other values of L1/L3, when the value is more than or equal to 0.5 and less than or equal to L1/L3 and less than or equal to 2, the effect of mutual cancellation of the magnetic field generated by the first tab and the magnetic field generated by the first connecting piece is better, and the difference of the magnetic field intensity at each position of the top wall side of the electrochemical device is smaller. Compared with other values of L2/L4, when L2/L4 is more than or equal to 0.5 and less than or equal to 2, the effect of mutual cancellation of the magnetic field generated by the second lug and the magnetic field generated by the second connecting piece is better, and the difference of the magnetic field intensity at each position of the bottom wall side of the electrochemical device is smaller.

In some embodiments of the present application, the electrochemical device further satisfies at least one of the following conditions (1) to (4): (1) the first and second tabs are located at opposite sides of the electrode assembly; (2) the top wall is provided with a first surface and a second surface which are opposite, the top wall is provided with a through hole which penetrates through the first surface and the second surface, and the first electrode is arranged in the through hole; (3) an insulating part is arranged between the top wall and the first electrode; (4) the housing includes a metallic material.

In a second aspect of the present application, there is also provided an electrical device comprising the electrochemical device in any one of the above embodiments. The electrochemical device can weaken the magnetic field generated by the electrochemical device, has better electromagnetic property, and reduces the influence of the magnetic field on electric equipment.

Drawings

Fig. 1 is a first view of an electrochemical device in one embodiment of the present application.

Fig. 2 is a second view of an electrochemical device in an embodiment of the present application.

Fig. 3 is a partial sectional view of an electrochemical device in an embodiment of the present application.

Fig. 4 is a schematic structural diagram of a first electrode in an embodiment of the present application.

Fig. 5 is a first view of an electrode assembly, a first tab and a second tab in an embodiment of the present application.

Fig. 6 is a second view of the electrode assembly, the first tab and the second tab in an embodiment of the present application.

Fig. 7 is a third view of an electrochemical device in an embodiment of the present application.

Fig. 8 is a third view of the electrode assembly, the first tab and the second tab in an embodiment of the present application.

Fig. 9 is a fourth view of an electrochemical device in another embodiment of the present application.

Fig. 10 is a fifth view of an electrochemical device in an embodiment of the present application.

Fig. 11 is a sixth view of an electrochemical device in an embodiment of the present application.

Fig. 12 is a schematic structural diagram of an electric device in an embodiment of the present application.

Description of the main elements

Electrochemical device 100

Housing 1

Roof wall 11

First electrode 111

First portion 1111

Third surface 1111a

Second portion 1112

First surface 112

Second surface 113

Through hole 114

Side wall 12

Bottom wall 13

Conductive part 131

Volume space 14

Electrode assembly 2

First pole piece 21

First active material layer 211

First end 2111

Second pole piece 22

Second active material layer 221

Second end 2211

Isolation diaphragm 23

First tab 3

First connection region 31

Second tab 4

Second attachment region 41

Third attachment zone 42

First connecting member 5

Fourth attachment region 51

Second connecting piece 6

Fifth attachment zone 61

Insulating member 7

Line W1 connecting the geometric center of the fourth connection region and the geometric center of the first electrode

Line W2 connecting the geometric center of the first connection region and the geometric center of the first electrode

Line W3 drawn between the geometric center of the fifth linking area and the geometric center of the third linking area

Line W4 drawn between the geometric center of the second linking area and the geometric center of the third linking area

A line segment length L1 between the geometric center of the first connection region and the geometric center of the first electrode

Length of line segment L2 between geometric center of second attachment zone and geometric center of third attachment zone

Length L3 of line segment between geometric center of fourth connection region and geometric center of first electrode

Length of line segment L4 between geometric center of fifth attachment zone and geometric center of third attachment zone

First region A1

Second region A2

Third region A3

Power utilization device 200

The device body 210

First direction X

Second direction Y

Third direction Z

The following detailed description will further illustrate the present application in conjunction with the above-described figures.

Detailed Description

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments.

It will be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. When an element is referred to as being "on" another element, it can be directly on the other element or intervening elements may also be present.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

In a first aspect of the present application, there is provided an electrochemical device including a case and an electrode assembly accommodated in the case. The shell comprises a top wall, a side wall and a bottom wall, and the top wall is provided with a first electrode. The electrode assembly includes a first pole piece and a second pole piece. The electrochemical device satisfies at least one of the following conditions (i) to (ii): (i) the electrochemical device further comprises a first tab and a first connecting member disposed outside the housing. The first tab is connected with the first pole piece and the first electrode, and the first tab comprises a first connecting area connected with the first pole piece. The first connecting piece is connected with the first electrode. Viewed in a direction perpendicular to the top wall, a connecting line between the geometric center of the first connection region and the geometric center of the first electrode is a first reference line, the geometric center of the first electrode is taken as a circle center, a line length L1 between the geometric center of the first connection region and the geometric center of the first electrode is taken as a radius, sector areas of +/-45 degrees on two sides of the first reference line are first areas, the area of the first connecting piece is S1, and the area of an overlapping part of the first connecting piece and the first areas is S2, so that the requirements that: S2/S1 is more than or equal to 50 percent. (ii) The electrochemical device also includes a second tab and a second connecting member disposed outside the housing. The second pole lug is connected with the second pole piece and the shell, and the second pole lug comprises a second connecting area connected with the second pole piece and a third connecting area connected with the shell. The second connecting piece is connected with the shell. Viewed in a direction perpendicular to the bottom wall, a connecting line between the geometric center of the second connecting area and the geometric center of the third connecting area is a second reference line, the geometric center of the third connecting area is taken as a circle center, a line segment length L2 between the geometric center of the second connecting area and the geometric center of the third connecting area is taken as a radius, fan-shaped areas of +/-45 degrees on both sides of the second reference line are second areas, the area of the second connecting piece is S3, and the area of an overlapping portion of the second connecting piece and the second areas is S4, so that the following requirements are met: S4/S3 is more than or equal to 50 percent. When the electrochemical device is in a charging/discharging state, the magnetic field generated by the first pole lug and the magnetic field generated by the first connecting piece can be at least partially offset, and/or the magnetic field generated by the second pole lug and the magnetic field generated by the second connecting piece can be at least partially offset, so that the magnetic field generated by the end face of the electrochemical device is weakened. Compared with other values of S2/S1 and/or S4/S3, when the ratio of S2/S1 is more than or equal to 50% and/or the ratio of S4/S3 is more than or equal to 50%, the magnetic field on the end face of the electrochemical device is weaker, and the electromagnetic interference on electric equipment is smaller.

As an example, the electrochemical device is placed on a horizontal plane, the bottom wall is below, and the top wall is above.

Embodiments of the present application will be further described with reference to the accompanying drawings.

As shown in fig. 1, 2 and 3, the embodiment of the present application provides an electrochemical device 100, the electrochemical device 100 including a case 1, an electrode assembly 2, a first tab 3, a second tab 4, a first connecting member 5 and a second connecting member 6. An electrode assembly 2, a first tab 3 and a second tab 4 are provided inside the case 1, and the electrode assembly 2 connects the first tab 3 and the second tab 4. The first connecting piece 5 and the second connecting piece 6 are arranged outside the shell 1, the first connecting piece 5 is electrically connected with the first lug 3, and the second connecting piece 6 is electrically connected with the second lug 4. The first connector 5 and the second connector 6 may be used to externally connect electric devices so that the electrochemical device 100 can supply power to the electric devices.

The casing 1 includes a top wall 11, a side wall 12 and a bottom wall 13, the top wall 11, the side wall 12 and the bottom wall 13 enclose to form a cavity space 14, and the electrode assembly 2, the first tab 3 and the second tab 4 are disposed in the cavity space 14.

The top wall 11 is provided with a first electrode 111, and the first electrode 111 connects the first tab 3 and the first connecting member 5.

In one embodiment, the top wall 11 is provided with a through hole 114 and comprises a first surface 112 and a second surface 113 facing away from each other, the through hole 114 penetrates through the first surface 112 and the second surface 113, the first surface 112 is located on a side of the top wall 11 facing the cavity space 14, and the second surface 113 is located on a side of the top wall 11 facing away from the cavity space 14.

At least a portion of the first electrode 111 is disposed within the via 114. In one embodiment, the electrochemical device 100 further includes an insulating member 7, the insulating member 7 is disposed between the top wall 11 and the first electrode 111, and the insulating member 7 connects the top wall 11 and the first electrode 111 to insulate the top wall 11 from the first electrode 111, thereby reducing the risk of short circuit of the electrochemical device 100.

In one embodiment, the material of the first electrode 111 includes, but is not limited to, aluminum or copper.

In one embodiment, the bottom wall 13 includes a conductive portion 131, and the conductive portion 131 connects the second tab 4 and the second connector 6, so that the second tab 4 and the second connector 6 are electrically connected. In one embodiment, the conductive portion 131 includes a metal material.

In an embodiment, the first connection member 5 comprises a metallic material. In an embodiment, the second connector 6 comprises a metallic material.

In other embodiments, the first electrode 111 can also be disposed in the through hole 114 (not shown), and the insulating member 7 is disposed between the first electrode 111 and the inner wall of the through hole 114.

As shown in fig. 3 and 4, the first electrode 111 includes a first portion 1111 and a second portion 1112.

The first portion 1111 has a third surface 1111a, and the second portion 1112 extends out of the third surface 1111 a.

The first portion 1111 is disposed within the plenum 14 and the second portion 1112 is disposed within the through hole 114.

For convenience of understanding and description, the third direction Z is taken as a direction perpendicular to the top wall 11, and the length direction of the first connecting member 5 is the first direction X and the length direction of the second connecting member 6 is the second direction Y when viewed along the third direction Z.

In one embodiment, the insulator 7 is a ring-shaped structure through which the second portion 1112 of the first electrode 111 passes.

In one embodiment, the insulator 7 includes, but is not limited to, a sealant.

As shown in fig. 5 and 6, the electrode assembly 2 includes a first pole piece 21, a second pole piece 22, and a separator 23, the separator 23 being disposed between the first pole piece 21 and the second pole piece 22. In one embodiment, the first pole piece 21, the separator 23 and the second pole piece 22 are wound.

One of the first pole piece 21 and the second pole piece 22 is a positive pole piece, and the other is a negative pole piece.

One of the first tab 3 and the second tab 4 is a positive tab, and the other is a negative tab.

The first pole piece 21 includes a first active material layer 211, the first tab 3 has a first connection region 31, and the first tab 3 is connected to the first pole piece 21 at the first connection region 31.

The second pole piece 22 includes a second active material layer 221, the second pole ear 4 has a second connection region 41, and the second pole ear 4 is connected to the second pole piece 22 at the second connection region 41.

In one embodiment, the first tab 3 is located on one side of the electrode assembly 2 and the second tab 4 is located on the opposite side of the electrode assembly 2. In other embodiments, the first tab 3 and the second tab 4 may also be located on the same side of the electrode assembly 2 (not shown).

The electrode assembly 2 is in a wound structure. In one embodiment, the first active material layer 211 includes a first end portion 2111, the first end portion 2111 is disposed at a winding start end of the winding structure, and the second active material layer 221 includes a second end portion 2211, the second end portion 2211 is disposed at the winding start end of the winding structure.

The distance D1 is measured along the length of the first pole piece 21 from the geometric center of the first attachment area 31 to the first end 2111. The distance between the geometric center of the second attachment zone 41 and the second end 2211 along the length of the second pole piece 22 is D2. Optionally, D1/D2 is more than or equal to 0.5 and less than or equal to 2.

When the electrochemical device 100 is in the charge/discharge state, the current flowing from the first end 2111 to the first connection region 31 is in the opposite direction to the current flowing from the second end 2211 to the second connection region 41, and the magnetic fields generated by the opposite currents in the first pole piece 21 and the second pole piece 22 can at least partially cancel each other, thereby reducing the influence of the magnetic field generated by the electrochemical device 100 on the electric equipment.

Further optionally, D1/D2 is more than or equal to 0.9 and less than or equal to 1.1. When D1/D2 is not less than 0.9 and not more than 1.1, the effect of mutual cancellation of the magnetic field generated by the first pole piece 21 and the magnetic field generated by the second pole piece 22 is better, and the difference of the magnetic field intensity at each position of the end face of the electrochemical device 100 is smaller.

Referring to fig. 1, 2 and 3, the second tab 4 further has a third connection region 42, and the second tab 4 is connected to the conductive portion 131 of the bottom wall 13 at the third connection region 42.

The end of the first connecting element 5 away from the first electrode 111 is provided with a fourth connecting area 51, the end of the second connecting element 6 away from the third connecting area 42 is provided with a fifth connecting area 61, and the fourth connecting area 51 and the fifth connecting area 61 can be used for externally connecting electric equipment, so that the electrochemical device 100 can be electrically connected with the electric equipment.

Referring to fig. 5, 6 and 7, when viewed along the third direction Z, a connection line between the geometric center of the fourth connection region 51 and the geometric center of the first electrode 111 is W1, a connection line between the geometric center of the first connection region 31 and the geometric center of the first electrode 111 is W2, and an included angle between the connection line W1 and the connection line W2 is θ.

In the present application, θ is an angle between a ray passing through the geometric center of the fourth connection region 51 and a ray passing through the geometric center of the first connection region 31, with the geometric center of the first electrode 111 as an end point, as viewed in the third direction Z.

In one embodiment, θ is 0 ≦ 45. When the electrochemical device 100 is in the charge/discharge state, the flow directions of the current on the first tab 3 and the first connecting member 5 tend to be opposite to each other as viewed along the third direction Z, and the magnetic field generated by the first tab 3 and the magnetic field generated by the first connecting member 5 can at least partially cancel each other out, so that the magnetic field generated by the top wall 11 side of the electrochemical device 100 is weakened, and the influence of the magnetic field generated by the electrochemical device 100 on the electric equipment is further reduced. Compared with the angle theta larger than 45 degrees, when the angle theta is smaller than or equal to 45 degrees, the effect of mutual offset of the magnetic field generated by the first tab 3 and the magnetic field generated by the first connecting piece 5 is better, and the electromagnetic property of the electrochemical device 100 is better.

Viewed in the third direction Z, a line connecting the geometric center of the fifth linking region 61 to the geometric center of the third linking region 42 is W3, a line connecting the geometric center of the second linking region 41 to the geometric center of the third linking region 42 is W4, and an angle β between the line W3 and the line W4 is included.

In the present application, β is the angle between a ray through the geometric center of the fifth connecting region 61 and a ray through the geometric center of the second connecting region 41, as viewed in the third direction Z, with the geometric center of the third connecting region 42 as an end point.

In one embodiment, β is 0 ≦ 45. When the electrochemical device 100 is in the charging/discharging state, the current flow directions on the second pole ear 4 and the second connecting member 6 tend to be opposite to each other as viewed along the third direction Z, and the magnetic field generated by the second pole ear 4 and the magnetic field generated by the second connecting member 6 can at least partially cancel each other out, so that the magnetic field generated by the bottom wall 13 of the electrochemical device 100 is weakened, and the influence of the magnetic field generated by the electrochemical device 100 on the electric equipment is reduced. Compared with beta larger than 45 degrees, when beta is smaller than or equal to 45 degrees, the effect that the magnetic field and the inductance generated by the second pole ear 4 and the magnetic field and the inductance generated by the second connecting piece 6 are mutually offset is better, and the electromagnetic property of the electrochemical device 100 is better.

Viewed in the third direction Z, the line length between the geometric center of the first connection region 31 and the geometric center of the first electrode 111 is L1, and the line length between the geometric center of the fourth connection region 51 and the geometric center of the first electrode 111 is L3.

Optionally, L1/L3 is more than or equal to 0.5 and less than or equal to 2. Compared with other values of L1/L3, when L1/L3 is greater than or equal to 0.5 and less than or equal to 2, the effect of mutual cancellation of the magnetic field generated by the first tab 3 and the magnetic field generated by the first connecting piece 5 is better, and the influence of the magnetic field generated by the electrochemical device 100 on the electric equipment is smaller. Optionally, L1/L3 is more than or equal to 0.9 and less than or equal to 1.1.

The segment length between the geometric center of the second attachment zone 41 and the geometric center of the third attachment zone 42, viewed in the third direction Z, is L2, and the segment length between the geometric center of the fifth attachment zone 61 and the geometric center of the third attachment zone 42 is L4.

In one embodiment, 0.5 ≦ L2/L4 ≦ 2. Compared with other values of L2/L4, when L2/L4 is greater than or equal to 0.5 and less than or equal to 2, the effect of mutual cancellation of the magnetic field generated by the second pole ear 4 and the magnetic field generated by the second connecting piece 6 is better, and the influence of the magnetic field generated by the electrochemical device 100 on the electric equipment is smaller. Optionally, L2/L4 is more than or equal to 0.9 and less than or equal to 1.1.

In one embodiment, the angle between the connecting line W2 and the connecting line W4 is α, optionally, 0 ° ≦ α ≦ 60 °. When the electrochemical device 100 is in a charging/discharging state, the magnetic field generated by the first tab 3 and the magnetic field generated by the second tab 4 may at least partially cancel each other out, so that the magnetic field generated by the electrochemical device 100 as a whole is weakened, and the influence of the magnetic field generated by the electrochemical device 100 on the electric equipment is reduced. In the present application, the angle α is the angle between the ray from the intersection point of the connecting line W2 and the connecting line W4 or extensions thereof to the geometric center of the first connecting region 31 and the ray from the intersection point to the geometric center of the second connecting region 41.

As shown in fig. 8 and 9, when viewed along the third direction Z, the connection line W2 is taken as a first reference line, the geometric center of the first electrode 111 is taken as a center of a circle, the length L1 of the line is taken as a radius, the sector areas of ± 45 ° on both sides of the first reference line are taken as a first area a1, the area of the first connection element 5 is taken as S1, and the area of the overlapping portion of the first connection element 5 and the first area a1 is taken as S2.

Optionally, S2/S1 is more than or equal to 50 percent. Compared with the situation that S2/S1 is less than 50%, when S2/S1 is more than or equal to 50%, the effect that the magnetic field generated by the first tab 3 and the magnetic field generated by the first connecting piece 5 are mutually counteracted is better, and the influence of the magnetic field generated by the top wall 11 side of the electrochemical device 100 on electric equipment is smaller.

Optionally, S2/S1 is more than or equal to 70 percent. When the ratio of S2/S1 is more than or equal to 70%, the effect of mutual cancellation of the magnetic field generated by the first tab 3 and the magnetic field generated by the first connecting piece 5 is better, and the difference of the magnetic fields at the side of the top wall 11 is smaller.

In an embodiment, when viewed along the third direction Z, the connection line W4 is taken as a second reference line, the geometric center of the third connecting region 42 is taken as a center of a circle, the length L2 is taken as a radius, the sector areas of ± 45 ° on both sides of the second reference line are taken as a second area a2, the area of the second connecting element 6 is taken as S3, and the area of the overlapping portion of the second connecting element 6 and the second area a2 is taken as S4.

Optionally, S4/S3 is more than or equal to 50 percent. Compared with the situation that S4/S3 is less than 50%, when S4/S3 is greater than or equal to 50%, the effect that the magnetic field generated by the second lug 4 and the magnetic field generated by the second connecting piece 6 are mutually counteracted is better, and the influence of the magnetic field generated by the bottom wall 13 side of the electrochemical device 100 on the electric equipment is smaller.

Further, S4/S3 is not less than 70%. When the ratio of S4/S3 is 70% or more, the effect of the magnetic field generated by the second pole piece 4 and the magnetic field generated by the second connecting member 6 canceling each other is better, and the difference of the magnetic fields at the bottom wall 13 side is smaller.

As shown in fig. 10 and 11, in an embodiment, when viewed along the third direction Z, the connection line W1 is taken as a third reference line, the geometric center of the first electrode 111 is taken as a center of a circle, the length L3 is taken as a radius, a sector area of ± 45 ° on both sides of the third reference line is a third area A3, and an area of an overlapping portion of the second connection member 6 and the third area A3 is S5.

In one embodiment, S5/S3 is greater than or equal to 50%. When the electrochemical device 100 is in the charge/discharge state, the magnetic field generated by the first connecting member 5 and the magnetic field generated by the second connecting member 6 may at least partially cancel each other out, so that the magnetic field generated by the electrochemical device 100 as a whole is weakened, and the influence of the magnetic field generated by the electrochemical device 100 on the electric equipment is reduced.

Optionally, S5/S3 is more than or equal to 85 percent. When the ratio S5/S3 is 85% or more, the effect of canceling out the magnetic field generated by the first connecting member 5 and the magnetic field generated by the second connecting member 6 is more excellent, and the difference between the magnetic fields at the top wall 11 side and the bottom wall 13 side of the electrochemical device 100 is smaller.

To verify the reduction effect of the present application on the magnetic field generated by the electrochemical device 100, the following comparative tests were performed:

test one:

the magnetic flux density B on the top wall 11 side was recorded by changing the values of S2/S1 and the angle θ, with the first tab being the positive tab and the second tab being the negative tab, the angle β being 0 °, the value of S4/S3 being 100%, the angle α being 0 °, and the angle D1/D2 being 0.9418.

In this application, the magnetic flux density is also referred to as the magnetic induction density, and can be used to indicate the strength of the magnetic field. The larger the value of the magnetic flux density, the stronger the magnetic field, and the smaller the weakening effect on the magnetic field generated by the electrochemical device 100; the smaller the value of the magnetic flux density, the weaker the magnetic field, and the greater the weakening effect on the magnetic field generated by the electrochemical device 100.

TABLE 1 comparison of records from different S2/S1

As is clear from Table 1, the magnetic flux density B was about 4.56X 10 when S2/S1 was 100% and θ was 0%^-6T; when S2/S1 was 50% and θ was 47 °, the magnetic flux density B was about 6.73X 10^-6T (about 1.48 times of 100% for S2/S1 and 0 ° for theta); when S2/S1 was 0% and θ was 70 °, the magnetic flux density B was about 7.47X 10^-6T (about 1.64 times of 100% for S2/S1 and 0 ° for theta); when S2/S1 was 0% and θ was 180 °, the magnetic flux density B was about 9.83X 10^-6T (about 2.16 times of that at 100% for S2/S1 and 0 ℃ for theta).

When S2/S1 is 100%, the projection of the first connecting member 5 overlaps the projection of the first region a1 as viewed in the third direction Z, and the electromagnetic characteristics of the electrochemical device 100 are better. As the value of the included angle θ becomes smaller, the electromagnetic characteristics of the electrochemical device 100 are gradually optimized.

And (2) test II:

the first tab was a positive tab, the second tab was a negative tab, the angle θ was 0 °, the value of S2/S1 was 100%, the angle β was 0 °, the values of S5/S3, the angles α and D1/D2 were changed, and the magnetic flux density B1 on the top wall 11 side and the magnetic flux density B2 on the bottom wall 13 side were recorded.

TABLE 2 comparison of records from different S5/S3

As can be seen from Table 2, the magnetic flux density B1 was about 4.560X 10 when S5/S3 was 100% and α was 0 °^-6T, magnetic flux density B2 of about 3.390X 10^-6And T. When S5/S3 was 55% and α was 45 °, the magnetic flux density B1 was about 5.265X 10^-6T (about 1.15 times of 100% for S5/S3 and 0 DEG. alpha.) and a magnetic flux density B2 of about 4.115X 10^-6T (about 1.21 times of 100% for S5/S3 and 0 ℃ for alpha). When S5/S3 was 0% and α was 90 °, the magnetic flux density B1 was about 5.940X 10^-6T (about 1.30 times of 100% for S5/S3 and 0 DEG for alpha), and B2, which is a magnetic flux density of about 4.850X 10^-6T (about 1.43 times of 100% for S5/S3 and 0 ℃ for alpha).

When S5/S3 is 100%, the projection of the second connection member 6 overlaps the projection of the third region A3 when viewed in the third direction Z, and the electromagnetic characteristics of the electrochemical device 100 are better. As the value α becomes smaller, the electromagnetic characteristics of the electrochemical device 100 become more optimized, and the magnetic flux density on the top wall 11 side and the bottom wall 13 side of the electrochemical device 100 further decreases significantly.

As shown in fig. 12, the embodiment of the present application further provides an electric device 200, where the electric device 200 includes a device body 210 and the electrochemical device 100 according to any of the above embodiments, and the electrochemical device 100 is disposed on the device body 210. The electrochemical device 100 can weaken the magnetic field generated by itself, has good electromagnetic characteristics, and weakens the influence of the magnetic field on the electric equipment 200.

In addition, other changes may be made by those skilled in the art within the spirit of the present application, and it is understood that such changes are encompassed within the scope of the present disclosure.

Claims

1. An electrochemical device, comprising:

the device comprises a shell, a first electrode and a second electrode, wherein the shell comprises a top wall, a side wall and a bottom wall;

an electrode assembly housed within the case, the electrode assembly including a first pole piece and a second pole piece;

characterized in that at least one of the following conditions (i) to (ii) is satisfied:

(i) the electrochemical device further includes:

a first tab connecting the first pole piece and the first electrode, the first tab including a first connection region connected with the first pole piece;

the first connecting piece is arranged outside the shell and connected with the first electrode;

viewed in a direction perpendicular to the top wall, a connecting line between a geometric center of the first connection region and a geometric center of the first electrode is a first reference line, the geometric center of the first electrode is taken as a center of a circle, a line length L1 between the geometric center of the first connection region and the geometric center of the first electrode is taken as a radius, fan-shaped regions of ± 45 ° on both sides of the first reference line are first regions, an area of the first connection element is S1, and an area of an overlapping portion of the first connection element and the first region is S2, so that: S2/S1 is more than or equal to 50 percent;

(ii) the electrochemical device further includes:

the second pole piece is connected with the shell, and the second pole piece comprises a second connecting area connected with the second pole piece and a third connecting area connected with the shell;

the second connecting piece is arranged outside the shell and connected with the shell;

viewed in a direction perpendicular to the bottom wall, a connecting line between a geometric center of the second connecting region and a geometric center of the third connecting region is a second reference line, the geometric center of the third connecting region is taken as a center of a circle, a line length L2 between the geometric center of the second connecting region and the geometric center of the third connecting region is taken as a radius, fan-shaped regions at two sides of the second reference line, which are +/-45 degrees, are second regions, an area of the second connecting member is S3, and an area of an overlapping portion of the second connecting member and the second regions is S4, so that: S4/S3 is more than or equal to 50 percent.

2. The electrochemical device according to claim 1, wherein at least one of the following conditions (iii) to (iv) is satisfied:

(iii)S2/S1≥70％；

(iv)S4/S3≥70％。

3. the electrochemical device according to claim 1, wherein at least one of the following conditions (v) to (vi) is satisfied:

(v) a fourth connecting region is arranged at the end part, far away from the first electrode, of the first connecting piece;

an angle θ formed by a connecting line between the geometric center of the fourth connection region and the geometric center of the first electrode and a connecting line between the geometric center of the first connection region and the geometric center of the first electrode, as viewed in a direction perpendicular to the top wall, satisfies: theta is more than or equal to 0 degree and less than or equal to 45 degrees;

(vi) a fifth connecting area is arranged at the end part, far away from the third connecting area, of the second connecting piece;

viewed in a direction perpendicular to the bottom wall, an included angle β between a line connecting the geometric center of the fifth connecting area and the geometric center of the third connecting area and a line connecting the geometric center of the second connecting area and the geometric center of the third connecting area satisfies: beta is more than or equal to 0 degree and less than or equal to 45 degrees.

4. The electrochemical device according to claim 1,

a fourth connecting region is arranged at the end part, far away from the first electrode, of the first connecting piece;

viewed in a direction perpendicular to the top wall, a connecting line between a geometric center of the fourth connecting area and a geometric center of the first electrode is a third reference line, the geometric center of the first electrode is taken as a center of a circle, a line length L3 between the geometric center of the fourth connecting area and the geometric center of the first electrode is taken as a radius, fan-shaped regions of ± 45 ° on both sides of the third reference line are third regions, and an area of an overlapping portion of the second connecting element and the third regions is S5, so that: S5/S3 is more than or equal to 50 percent.

5. The electrochemical device of claim 4, wherein a ratio of said area S5 to said area S3 satisfies: S5/S3 is more than or equal to 85 percent.

6. The electrochemical device of claim 4 wherein said first reference line and said second reference line, as viewed in a direction perpendicular to said top wall, form an angle α that satisfies: alpha is more than or equal to 0 degree and less than or equal to 60 degrees.

7. The electrochemical device according to claim 1,

the electrode assembly is in a coiled structure;

the first pole piece comprises a first active material layer, the first active material layer comprises a first end part, and the first end part is arranged at the winding starting end of the winding structure;

the second pole piece comprises a second active material layer, the second active material layer comprises a second end part, and the second end part is arranged at the winding starting end of the winding structure;

a distance D1 between a geometric center of the first attachment region and the first end along a length of the first pole piece; the distance between the geometric center of the second connection region and the second end portion in the length direction of the second pole piece is D2, satisfying: D1/D2 is more than or equal to 0.5 and less than or equal to 2.

8. The electrochemical device according to claim 1, wherein at least one of the following conditions (a) to (b) is satisfied:

(a) a fourth connecting region is arranged at the end part, far away from the first electrode, of the first connecting piece; a line segment length between a geometric center of the fourth connection region and a geometric center of the first electrode, as viewed in a direction perpendicular to the top wall, is L3, satisfying: L1/L3 is more than or equal to 0.5 and less than or equal to 2;

(b) a fifth connecting area is arranged at the end part, far away from the third connecting area, of the second connecting piece; a line segment length between a geometric center of the fifth joint region and a geometric center of the third joint region, as viewed in a direction perpendicular to the bottom wall, is L4, satisfying: L2/L4 is more than or equal to 0.5 and less than or equal to 2.

9. The electrochemical device according to claim 1, wherein at least one of the following conditions (1) to (4) is satisfied:

(1) the first and second tabs are located at opposite sides of the electrode assembly;

(2) the top wall is provided with a first surface and a second surface which are opposite, the top wall is provided with a through hole which penetrates through the first surface and the second surface, and the first electrode is arranged in the through hole;

(3) an insulating part is arranged between the top wall and the first electrode;

(4) the housing includes a metallic material.

10. An electric device comprising the electrochemical device according to any one of claims 1 to 9.