CN220420822U - Battery cell - Google Patents

Abstract

The utility model discloses a battery, which comprises an electrode assembly and a cover plate assembly, wherein the length of a first tab of the electrode assembly is longer than that of a second tab; the cover plate assembly comprises a cover plate and a conductive member, wherein the cover plate is provided with an eccentric through hole deviating from the center of the cover plate; the conductive member penetrates through the eccentric through hole, the cover plate is provided with a first welding area, the conductive member is provided with a second welding area, the first welding area and the second welding area are respectively positioned at two sides of the eccentric through hole, a containing area is arranged between the cover plate and the electrode assembly, and the containing area is positioned at one side, close to the eccentric through hole, of the first welding area; the first tab is welded to the cover plate in a first welding area and is partially accommodated in the accommodating area, and the second tab is welded to the conductive member in a second welding area. According to the scheme, the accommodating area can exist between the conductive member and the first welding area, and the part, which is not welded with the cover plate, of the longer tab can be accommodated in the accommodating area, so that the arrangement requirement of the longer tab is met.

Description

Battery cell

Technical Field

The utility model relates to the technical field of batteries, in particular to a battery.

Background

Known, such as button cells, typically include an electrode assembly that is enclosed by and contained within a housing. The housing generally includes a top cover and a shell having a cavity. The electrode assembly is located in the receiving chamber of the case and covered by the top cap. The electrode assembly includes a positive tab generally drawn from the top and welded to the top cover, and a negative tab generally drawn from the bottom and welded to the bottom of the housing.

The bottom of shell belongs to welded blind area for the welding of negative pole utmost point ear belongs to blind welding, and the defective rate is high, and the finished product is low, and introduces the metal welding slag easily at welded in-process, causes the battery self-discharge bad, and full-weld welding yield is low after annotating the liquid influences efficiency.

Disclosure of Invention

A series of concepts in a simplified form are introduced in the summary of the utility model, which will be described in further detail in the detailed description. The summary of the utility model is not intended to limit the critical and essential features of the claimed subject matter, nor is it intended to be used to determine the scope of the claimed subject matter.

To at least partially solve the above problems, the present utility model provides a battery including:

an electrode assembly having first and second tabs of opposite polarity, the first tab having a length greater than a length of the second tab;

a cover plate assembly, the cover plate assembly comprising:

a cover plate having an eccentric through hole offset from a center of the cover plate; and

a conductive member penetrating through the eccentric through hole,

the cover plate is provided with a first welding area, the conductive member is provided with a second welding area, the first welding area and the second welding area are respectively positioned at two sides of the eccentric through hole, an accommodating area is arranged between the cover plate and the electrode assembly, and the accommodating area is positioned at one side, close to the eccentric through hole, of the first welding area;

wherein the first tab is welded to the cover plate in the first welding region and partially accommodated in the accommodating region, and the second tab is welded to the conductive member in the second welding region.

Optionally, a distance between a center of the eccentric through hole and a center of the cover plate is greater than or equal to 2mm.

Optionally, the conductive member is provided with a liquid injection hole therethrough, or the cover plate is provided with a liquid injection hole therethrough.

Optionally, a center line defined by a center of the cover plate and a center of the eccentric through hole extends through the first welding region.

Optionally, a center line defined by a center of the cover plate and a center of the eccentric through hole extends through a projection area of the second welding area on the cover plate.

Optionally, the conductive member includes a fixing piece and a connecting piece for welding with the second lug, the fixing piece is arranged through the eccentric through hole, and the connecting piece is fixed to the cover plate through the fixing piece.

Optionally, the fixing member includes a head portion located at an outer side of the cover plate and radially convexly disposed around the stem portion, the stem portion is disposed through the eccentric through hole, and a flange portion located at an inner side of the cover plate and radially convexly disposed around the stem portion, the connecting member and the cover plate being sandwiched between the head portion and the flange portion.

Optionally, all of the eccentric through holes are located at one side of the center of the cover plate; and/or the battery further comprises a case having a cavity, the case is connected with the cap plate, and the electrode assembly is accommodated in the cavity of the case and covered by the cap plate.

Optionally, the cover plate assembly further comprises an insulating seal located between the conductive member and the cover plate, the insulating seal being a separate member formed of injected sealing material or having a through hole.

Optionally, the first tab and the second tab are both led out from a side of the electrode assembly facing the cap plate assembly; and/or the first tab has a laminated structure formed by bending; and/or the battery is a button battery.

According to the battery provided by the utility model, the welding areas of the two lugs can be arranged far away from each other, so that the requirements of the two lugs on the welding position in the welding process can be met, the welding position is ensured to be in a required range, and therefore, the welding of the two lugs can be easily operated, and the welding tension is qualified. The mounting position of the conductive member is offset, i.e., offset from the center of the cover plate, so that there may be a receiving area between the conductive member and the first welding area, in which a portion of the longer tab that is not welded to the cover plate may be received, thereby satisfying the arrangement requirement of the longer tab.

The welding of the two tabs can adopt open welding, so that various problems caused by blind welding are effectively solved, such as high tab welding reject ratio and low finished product, and the problems of poor self-discharge of the battery and the like caused by the fact that metal welding slag is easily introduced in the welding process are effectively solved. And because there is not the solder joint of being connected with the utmost point ear in the casing for can accomplish the welding operation of utmost point ear earlier, annotate the liquid again, the product yield is higher, and efficiency is faster.

Drawings

The following drawings are included to provide an understanding of the utility model and are incorporated in and constitute a part of this specification. Embodiments of the present utility model and their description are shown in the drawings to explain the principles of the utility model.

In the accompanying drawings:

fig. 1 is a sectional view of a battery according to a preferred embodiment of the present utility model;

FIG. 2 is a top view of the battery shown in FIG. 1;

FIG. 3 is a cross-sectional view of the cover plate assembly shown in FIG. 1;

fig. 4 is an exploded perspective view of the battery shown in fig. 1;

FIG. 5 is a schematic view of the battery shown in FIG. 1 in a first welding position;

fig. 6 is a schematic view of the battery shown in fig. 1 in a second welding position.

Reference numerals illustrate:

1 Battery 10 electrode Assembly

11 first tab 12 second tab

13 separator layer 14 insulating layer

20 housing 30 cover plate assembly

31 cover plate 32 eccentric through hole

33 conductive member 34 liquid injection hole

35 fixing piece 36 connecting piece

37 head 38 stem

39 flange portion 40 insulating seal portion

41 sealing member 42 outer seal portion

43 inner seal portion

Detailed Description

In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present utility model. It will be apparent, however, to one skilled in the art that the utility model may be practiced without one or more of these details. In other instances, well-known features have not been described in detail in order to avoid obscuring the utility model.

In the following description, a detailed description will be given for the purpose of thoroughly understanding the present utility model. It will be apparent that embodiments of the utility model may be practiced without limitation to the specific details that are familiar to those skilled in the art. Preferred embodiments of the present utility model are described in detail below, however, the present utility model may have other embodiments in addition to these detailed descriptions.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the present utility model. As used herein, the singular is intended to include the plural unless the context clearly indicates otherwise. Furthermore, it will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

Ordinal numbers such as "first" and "second" cited in the present utility model are merely identifiers and do not have any other meaning, such as a particular order or the like. Also, for example, the term "first component" does not itself connote the presence of "second component" and the term "second component" does not itself connote the presence of "first component".

It should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "inner", "outer", and the like are used herein for illustrative purposes only and are not limiting.

Exemplary embodiments according to the present utility model will now be described in more detail with reference to the accompanying drawings. These exemplary embodiments may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. It should be appreciated that these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of these exemplary embodiments to those skilled in the art.

As shown in fig. 1, the present utility model provides a battery 1, and the illustrated embodiment schematically shows that the battery 1 is a button battery. Of course, the battery 1 may be other types of batteries. Button cells are specifically described herein as examples.

The battery 1 includes an electrode assembly 10, a case 20, and a cap plate assembly 30. The electrode assembly 10 has first and second tabs 11 and 12 having opposite polarities. For example, the first tab 11 may be a positive tab, and the second tab 12 may be a negative tab; alternatively, the first tab 11 may be a negative tab and the second tab 12 may be a positive tab. The case 20 has a receiving cavity, and the electrode assembly 10 is received in the receiving cavity of the case 20. The cover assembly 30 includes a cover 31. The housing 20 can be connected, for example welded, to the cover plate 31. The electrode assembly 10 is covered by a cap plate 31. It will be appreciated that both the housing 20 and the cover 31 are made of an electrically conductive material, such as an electrically conductive metallic material, i.e., both the housing 20 and the cover 31 are electrically conductive members.

As shown in fig. 1 to 4, the cover plate 31 has an eccentric through hole 32 offset from the center P1 of the cover plate 31. The cover assembly 30 further includes a conductive member 33, wherein the conductive member 33 is disposed through the eccentric through hole 32, and a part of the conductive member 33 protrudes from the outer surface of the cover 31, and another part of the conductive member protrudes from the inner surface of the cover 31. One of the first tab 11 and the second tab 12 can be connected to the cover plate 31, and the other can be connected to the conductive member 33.

In this embodiment, the two tabs are connected by welding, and further, the two tabs are welded to corresponding positions of the cover assembly 30 on the side of the battery 1 assembly facing the cover assembly 30. In order to facilitate the welding, the length of the first tab 11 is longer than that of the second tab 12, the first tab 11 with a longer length is welded with the cover plate 31, and the second tab 12 with a smaller length is welded with the conductive member 33.

Specifically, referring to fig. 1, the cap plate 31 may have a first welding region R11, and the conductive member 33 has a second welding region R12. The general locations of these areas are only substantially circled in fig. 1 with a dashed box, it being understood that these areas refer to the areas of the cover assembly 30 on the side facing the cell 1 assembly. The cap plate 31 has a receiving region R2 between the electrode assembly 10. As can be seen from fig. 1, the first welding region R11 and the second welding region R12 can be located at both sides of the eccentric through hole 32, respectively, and the receiving region R2 is located at a side of the first welding region R11 close to the eccentric through hole 32. The first tab 11 is welded to the cover plate 31 in the first welding region R11 and partially accommodated in the accommodating region R2, and the second tab 12 is welded to the conductive member 33 in the second welding region R12.

With this embodiment, the welding area of longer utmost point ear and shorter utmost point ear can set up to be far away from, can satisfy the demand of longer utmost point ear and shorter utmost point ear to welding position in the welding process, ensures that the welding position is in the within range that needs, and the welding of two utmost point ears from this can both be operated easily, and welding pulling force is qualified. After the welding is completed, the part of the longer tab, which is not welded to the cover plate 31, needs a certain accommodation position, and the present embodiment biases the installation position of the conductive member 33, that is, the installation position is offset from the center P1 of the cover plate 31, so that an accommodation region R2 may exist between the conductive member 33 and the first welding region R11, and the part of the longer tab, which is not welded to the cover plate 31, may be accommodated in the accommodation region R2, thereby satisfying the arrangement requirement of the longer tab.

The welding of two tabs of this embodiment can all adopt the open welding, has effectively solved various problems that bring because of blind welding, for example has effectively solved tab welding reject ratio height, finished product low, and introduces the metal welding slag easily at welded in-process, causes battery 1 self-discharge bad scheduling problem. And because there is not the solder joint of being connected with the utmost point ear in the casing 20 for can accomplish the welding operation of utmost point ear earlier, annotate the liquid again, the product yield is higher, and efficiency is faster.

The first tab 11 and the second tab 12 may each be drawn from a side of the electrode assembly 10 facing the cap plate assembly 30. The first tab 11 may have a laminated structure formed by bending. For example, as shown in fig. 1, the first tab 11 is bent twice to form a double-layer structure, and the second tab 12 is bent once to form a single-layer structure. Specifically, the first tab 11 is led out from one peripheral position of the electrode assembly 10, bent toward the center of the assembly of the battery 1, and then bent reversely. The second tab 12 is led out from the other peripheral position of the electrode assembly 10 and bent toward the center of the battery 1 assembly.

All of the eccentric through holes 32 are located at one side of the center P1 of the cover plate 31. That is, the eccentric through hole 32 does not pass through the center P1 of the cover plate 31. Of course, a small portion of the eccentric through-hole 32 may span the center P1 of the cover plate 31, if needed and/or desired. It will be appreciated that the center P1 of the cap plate 31 is collinear with the center of the case and the center of the electrode assembly 10.

Referring to fig. 2, a center line L defined by a center P1 of the cover plate 31 and a center P2 of the eccentric through hole 32 extends through the first welding region R11, for example, the first welding region R11 is symmetrical with respect to the center line L, whereby the first tab 11 can be disposed along the center line L; the center line L defined by the center P1 of the cover plate 31 and the center P2 of the eccentric through hole 32 extends through a projection area of the second welding area R12 on the cover plate 31, for example, a projection area of the second welding area R12 on the cover plate 31 is symmetrical with respect to the center line L, whereby the second lug 12 can be arranged along the center line L. Of course, the first welding region R11 may be offset from the center line L defined by the center P1 of the cover plate 31 and the center P2 of the eccentric through hole 32, if needed and/or desired; the projection area of the second welding area R12 on the cover plate 31 may also be offset from the center line L defined by the center P1 of the cover plate 31 and the center P2 of the eccentric through hole 32.

The distance D between the center P2 of the eccentric through hole 32 and the center P1 of the cover plate 31, i.e., the offset distance D, may be greater than or equal to 2mm, although the offset distance D may be set to be less than 2mm if needed and/or desired.

As shown in fig. 2 and 3, the conductive member 33 may be provided with a liquid injection hole 34 therethrough. After the welding operation of the tab and the cap plate 31 is completed, the electrolyte is injected through the electrolyte injection hole 34. Of course, alternatively, the liquid injection hole 34 may be provided through the cover plate 31.

As shown in fig. 3 and 4, the conductive member 33 may include a fixing piece 35 and a connecting piece 36 for welding with the second tab 12. The fixing member 35 can be inserted into the eccentric through hole 32, and a part of the fixing member 35 is exposed from the outside of the cover plate 31 and another part extends from the inside of the cover plate 31. The connection member 36 is located at the inner side of the cap plate 31, and the connection member 36 can be fixed to the cap plate 31 by the fixing member 35, whereby the connection member 36 is in direct contact with the fixing member 35 to be electrically conductive. It will be appreciated that both the fixing member 35 and the connecting member 36 are made of an electrically conductive material, such as an electrically conductive metal material, i.e. both the fixing member 35 and the connecting member 36 are electrically conductive members.

In one exemplary embodiment, the fixture 35 may include a head portion 37, a stem portion 38, and a flange portion 39 that are connected to one another. The head 37 is located outside the cover plate 31 and is arranged radially convexly around the stem 38. In other words, the head 37 circumferentially surrounds the stem 38 and radially protrudes from the stem 38. The stem portion 38 can be provided to pass through the eccentric through hole 32, and the flange portion 39 is located inside the cover plate 31 and radially convexly provided around the stem portion 38, in other words, the flange portion 39 circumferentially surrounds the stem portion 38 and radially protrudes from the stem portion 38. The dimension of the flange portion 39 protruding in the radial direction of the stem portion 38 is smaller than the dimension of the head portion 37 protruding in the radial direction. The connector 36 and the cover plate 31 can be sandwiched between the head 37 and the flange 39. The connecting member 36 may be annular and fit over the stem 38.

The cover plate assembly 30 also includes an insulating seal 40. The insulating seal 40 is located between the conductive member 33 and the cover plate 31, specifically between the fixing piece 35 and the cover plate 31, and between the connecting piece 36 and the cover plate 31. Whereby electrical contact between the cover plate 31 and the conductive member 33 can be avoided. Referring to fig. 3, the insulating seal 40 includes an outer seal portion 42 located outside the cap plate 31 and an inner seal portion 43 located inside the cap plate 31. The outer sealing portion 42 separates the head 37 of the conductive member 33 from the cover plate 31, and the inner sealing portion 43 separates the connector 36 from the cover plate 31. The outer seal portion 42 has a dimension in the radial direction of the conductive member 33 that is larger than the dimension in the radial direction of the head 37 of the conductive member 33; the inner seal portion 43 has a dimension in the radial direction of the conductive member 33 that is larger than the dimension of the connection piece 36 in the radial direction. The insulating sealing part 40 may be formed of an injected sealing material; the sealing material includes, for example, PFA (polytetrafluoroethylene (PFA) or any other suitable material. Alternatively, the insulating seal 40 may be a separate member with a through hole. The conductive member 33 is inserted into the through hole of the insulating sealing portion 40.

The fixing 35 may be, for example, a rivet, more particularly a duralumin rivet. The rivet has a head 37 and a stem 38 before being mounted, and a flange 39 of the rivet is formed by an external force after being inserted into the eccentric through hole 32 and the insulating seal 40 is formed.

Referring to fig. 4, the eccentric through-hole 32 is schematically shown as circular, and the annular connecting member 36 has a shape corresponding to the shape of the eccentric through-hole 32 and is circular. The fixing member 35 has a substantially circular shape corresponding to the shape of the eccentric through hole 32. Of course, the eccentric through-hole 32 may be of any suitable shape, square, rectangular, etc., as needed and/or desired, and the shape of the attachment 36 and securing member 35 may vary accordingly. The cover plate assembly 30 further comprises a sealing piece 41, and the sealing piece 41 can seal the liquid injection port. The sealing member 41 is, for example, a steel ball.

Referring back to fig. 1, the electrode assembly 10 further includes a separator layer 13 and an insulating layer 14. Separator layers 13 are provided at the upper and lower ends of the electrode assembly 10, and an insulating layer 14 is positioned above the separator layers 13 at the upper end of the electrode assembly 10. Alternatively, the separator layer 13 may be formed of separator paper, and the insulating layer 14 may be formed of a separate insulating sheet such as a high temperature glue spacer.

The welding process of the tab is described with reference to fig. 5 and 6.

The second tab 12 of smaller length is first welded. The independent cap plate assembly 30 is laid flat, and the electrode assembly 10 is placed perpendicular to the cap plate assembly 30, i.e., vertically. The second tab 12 is horizontally placed in a predetermined second welding region R12. The second tab 12 may be welded using a laser perpendicular to the cover plate assembly 30. Fig. 5 schematically shows the approximate location of the laser beam path.

After the welding of the second tab 12 is completed, the electrode assembly 10 is inclined toward the cap plate assembly 30, maintaining a certain inclination angle between the electrode assembly 10 and the cap plate assembly 30. For example, fig. 6 schematically shows that the inclination angle is 30 °. And the welding portion and the non-welding portion of the first tab 11 are disposed at right angles, the welding portion being horizontally disposed at a predetermined first welding region R11. The welding portion of the first tab 11 may be welded using a laser perpendicular to the cap plate assembly 30.

After the welding of the first tab 11 is completed, the first tab 11 is bent such that a portion thereof is positioned in the receiving region R2 between the cap plate 31 and the electrode assembly 10. The assembly of the cap plate assembly 30 and the electrode assembly 10 is completed. The electrode assembly 10 is then loaded into the case 20 and the cap plate 31 are laser welded. After the welding process, an electrolyte is injected through the injection port, and the battery 1 is sealed with the sealing member 41, thereby completing the manufacture of the battery.

Unless defined otherwise, technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model pertains. The terminology used herein is for the purpose of describing particular implementations only and is not intended to be limiting of the utility model. Features described herein in one embodiment may be applied to another embodiment alone or in combination with other features unless the features are not applicable or otherwise indicated in the other embodiment.

The present utility model has been described by way of the above embodiments, but it should be understood that the above embodiments are for illustrative and explanatory purposes only and that the utility model is not limited to the above embodiments, but is capable of numerous variations and modifications in accordance with the teachings of the utility model, all of which fall within the scope of the utility model as claimed.

Claims (10)

1. A battery, comprising:

an electrode assembly having first and second tabs of opposite polarity, the first tab having a length greater than a length of the second tab;

a cover plate assembly, the cover plate assembly comprising:

a cover plate having an eccentric through hole offset from a center of the cover plate; and

a conductive member penetrating through the eccentric through hole,

the cover plate is provided with a first welding area, the conductive member is provided with a second welding area, the first welding area and the second welding area are respectively positioned at two sides of the eccentric through hole, an accommodating area is arranged between the cover plate and the electrode assembly, and the accommodating area is positioned at one side, close to the eccentric through hole, of the first welding area;

wherein the first tab is welded to the cover plate in the first welding region and partially accommodated in the accommodating region, and the second tab is welded to the conductive member in the second welding region.

2. The battery of claim 1, wherein a distance between a center of the eccentric through hole and a center of the cap plate is greater than or equal to 2mm.

3. The battery according to claim 1, wherein the conductive member is provided with a liquid filling hole therethrough, or the cap plate is provided with a liquid filling hole therethrough.

4. The battery of claim 1, wherein a centerline defined by a center of the cover plate and a center of the eccentric through hole extends through the first welding region.

5. The battery of claim 1, wherein a centerline defined by a center of the cover plate and a center of the eccentric through hole extends through a projected area of the second welding area on the cover plate.

6. The battery according to claim 1, wherein the conductive member includes a fixing member penetrating the eccentric through hole and a connecting member for welding with the second tab, the connecting member being fixed to the cap plate by the fixing member.

7. The battery according to claim 6, wherein the fixing member includes a head portion, a rod portion, and a flange portion, the head portion being located outside the cap plate and being disposed around the rod portion radially protruding, the rod portion being provided through the eccentric through hole, the flange portion being located inside the cap plate and being disposed around the rod portion radially protruding, the connecting member and the cap plate being sandwiched between the head portion and the flange portion.

8. The battery according to any one of claim 1 to 7, wherein,

all the eccentric through holes are positioned on one side of the center of the cover plate; and/or

The battery further includes a case having a cavity, the case being connected with the cap plate, and the electrode assembly being received in the cavity of the case and covered by the cap plate.

9. The battery of any one of claims 1 to 7, wherein the cap plate assembly further comprises an insulating seal between the conductive member and the cap plate, the insulating seal being a separate member formed of an injected sealing material or having a through hole.

10. The battery according to any one of claim 1 to 7, wherein,

the first tab and the second tab are led out from one side of the electrode assembly facing the cover plate assembly; and/or

The first tab has a laminated structure formed by bending; and/or

The battery is a button battery.