CN219642898U

CN219642898U - Winding type battery

Info

Publication number: CN219642898U
Application number: CN202320625310.7U
Authority: CN
Inventors: 任涛; 刘宏勇; 黄亮; 覃律健; 于哲勋
Original assignee: Jiangsu Zenio New Energy Battery Technologies Co Ltd
Current assignee: Jiangsu Zenio New Energy Battery Technologies Co Ltd
Priority date: 2023-03-27
Filing date: 2023-03-27
Publication date: 2023-09-05
Anticipated expiration: 2033-03-27

Abstract

The utility model discloses a coiled battery, which comprises a first pole piece, a second pole piece and an interlayer piece, wherein a first coating area of the first pole piece, the interlayer piece and a second coating area of the second pole piece are sequentially attached to each other and coiled into the coiled battery along a first direction, and a tail-end empty foil area on the first pole piece can be attached to the coiling tail end of the coiled battery in a sealing way; the first empty foil area of the first pole piece and the second empty foil area of the second pole piece extend to the opposite ends of the battery along the second direction to form a positive electrode lug and a negative electrode lug respectively, and a positive compact surface and a negative compact surface are formed respectively through flattening, so that the two compact surfaces are covered at the two ends in a sealing way; the interlayer piece can electrically connect the first pole piece and the second pole piece. The battery can be directly electrically connected with the outside through the two compact surfaces, so that the setting of a top cover is canceled, the battery can be wrapped and sealed through the ending empty foil area, the setting of a shell is canceled, the whole thickness of the battery is reduced, the quality energy density is improved, and the cost is saved.

Description

Winding type battery

Technical Field

The utility model belongs to the technical field of power batteries, and particularly relates to a winding type battery.

Background

With the rapid development of new energy automobiles, lithium ion batteries are widely focused as important component parts, and with the increasing requirements of people on the cruising performance of the new energy automobiles, the lithium ion batteries are also required to have higher quality energy density.

To achieve the above object, there have been lithium ion batteries in the prior art that improve mass energy density by replacing a liquid electrolyte with a gel state electrolyte or an all solid state electrolyte. However, most of the enterprises at present only replace the liquid electrolyte with gel electrolyte or all-solid electrolyte, and most of the produced batteries still comprise a top cover and a shell, and the top cover and the shell still occupy a part of space and quality, so that the quality energy density of the batteries cannot be further improved.

Based on the foregoing, a need exists for a wound battery that solves the technical problems of the prior art.

Disclosure of Invention

The utility model aims to provide a winding type battery which can further improve the quality energy density of the battery and reduce the production and manufacturing cost.

To achieve the purpose, the utility model adopts the following technical scheme:

the winding type battery comprises a first pole piece, a second pole piece and an interlayer piece, wherein the first pole piece comprises a first coating area and a first empty foil area, the first coating area is used for coating a first active material, the first pole piece is provided with a tail empty foil area along a first direction, and the tail empty foil area can be sealed and attached to the winding tail end of the winding type battery;

the second electrode sheet comprises a second coating area and a second empty foil area, the second coating area is used for coating a second active material, the first coating area, the interlayer piece and the second coating area are sequentially attached to each other and wound into the coiled battery along the first direction, the first empty foil area and the second empty foil area extend out to form a positive electrode lug and a negative electrode lug respectively along the second direction, a positive compact surface and a negative compact surface are formed respectively through flattening, so that the positive compact surface and the negative compact surface are covered on the two ends of the coiled battery in a sealing mode, and the first direction is horizontal and perpendicular to the second direction;

the interlayer piece can enable the first pole piece and the second pole piece to be connected in a conductive mode.

Optionally, a solid electrolyte layer is coated on the first active material, and the solid electrolyte layer is the interlayer piece;

and/or the second active material is coated with the solid electrolyte layer.

Optionally, the interlayer member is a diaphragm, and opposite surfaces of the diaphragm are filled with gel-state electrolyte or liquid-state electrolyte.

Optionally, the gel state electrolyte is arranged on two opposite surfaces of the diaphragm, and the gel state electrolyte (4) is arranged in a lattice mode.

Optionally, in the second direction, two ends of the interlayer member respectively extend out of the first coating area and the second coating area.

Optionally, the length of the interlayer member extending from the second coating area along the second direction ranges from 0.5mm to 2mm.

Optionally, at least part of the interlayer member protrudes from the second coating area along the first direction.

Optionally, an insulating seal is also included, covering the ending blank foil region.

Optionally, the first active material is coated in the first coating area by adopting an intermittent coating mode, and the second active material is coated in the second coating area by adopting a continuous coating mode.

Optionally, one of the first pole piece and the second pole piece is aluminum foil, and the other is copper foil.

Compared with the prior art, the utility model has the beneficial effects that:

according to the winding type battery cell provided by the utility model, the two ends of the battery can be covered in a sealing way through the positive compact surface and the negative compact surface which are respectively formed by the positive electrode lug and the negative electrode lug, so that electrolyte in the battery can be prevented from leaking from the two ends, and the battery can be directly and electrically connected with the outside through the two compact surfaces, so that the setting of a top cover is eliminated; in addition, after the battery is wound, the winding end of the wound battery can be sealed and attached through the ending empty foil area arranged on the first pole piece, so that electrolyte in the battery can be prevented from leaking from the winding end, and the arrangement of the shell is canceled. Through the arrangement, the thickness of the whole winding type battery is effectively reduced, so that the quality energy density is improved, and the production and manufacturing cost is saved.

Drawings

Fig. 1 is a front view of a wound battery in the present utility model when it is not wound;

FIG. 2 is a front view of a first pole piece provided by the present utility model;

fig. 3 is a front view of a septum provided by the present utility model.

In the figure:

1. a first pole piece; 11. a first coating zone; 12. a first empty foil region; 13. a first active material; 14. ending the empty foil area;

2. a second pole piece; 21. a second coating zone; 22. a second empty foil region; 23. a second active material;

3. an interlayer member; 31. gel state electrolyte.

Detailed Description

In the description of the present utility model, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Wherein the terms "first position" and "second position" are two different positions.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixed or removable, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

The following description of the embodiments of the present utility model will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the utility model are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present utility model without making any inventive effort, are intended to be within the scope of the present utility model.

The wound battery provided by the present utility model is described below with reference to fig. 1 to 3 and the specific embodiment.

Referring to fig. 1, the wound battery comprises a first pole piece 1, a second pole piece 2 and a sandwich 3, wherein the first pole piece 1 comprises a first coating region 11 and a first empty foil region 12, the first coating region 11 is used for coating a first active material 13, and the first pole piece 1 is provided with a tail-out empty foil region 14 along a first direction; the second electrode sheet 2 comprises a second coating area 21 and a second empty foil area 22, the second coating area 21 is used for coating a second active material 23, the first coating area 11, the interlayer piece 3 and the second coating area 21 are sequentially attached and wound into the wound battery in a first direction (shown by arrow in reference to the implementation of fig. 1), the first empty foil area 12 and the second empty foil area 22 extend towards opposite ends of the wound battery in a second direction (shown by arrow in dotted line in reference to fig. 1) to form a positive electrode lug and a negative electrode lug, and a positive compact surface and a negative compact surface are respectively formed through a leveling treatment process, and the first direction and the second direction are horizontally vertical; the interlayer 3 can electrically connect the first pole piece 1 and the second pole piece 2, and can avoid the direct contact of the first active material 13 and the second active material 23, thereby preventing short circuit.

Through the arrangement, the two ends of the coiled battery can be covered in a sealing way through the positive compact surface and the negative compact surface, electrolyte in the battery can be prevented from leaking from the two ends, and the battery can be directly electrically connected with the outside through the positive compact surface and the negative compact surface, so that the arrangement of the existing top cover is cancelled; in addition, after the winding of the wound battery is completed, the winding end of the wound battery can be sealed and attached by the ending empty foil region 14 arranged on the first pole piece 1, and the electrolyte in the battery can be prevented from leaking from the winding end and the arrangement of a shell in the conventional battery can be canceled. The winding type battery eliminates the arrangement of the shell and the top cover, so that the thickness of the whole winding type battery can be effectively reduced, the quality energy density is improved, and the manufacturing cost for additionally arranging the shell and the top cover sheet is saved.

In this embodiment, the first electrode sheet 1 is defined as a positive electrode sheet, the second electrode sheet 2 is defined as a negative electrode sheet, and accordingly, the first active material 13 is a positive electrode active material, and the second active material 23 is a negative electrode active material, and the materials of the positive electrode active material and the negative electrode active material are not limited in the present utility model, and common positive electrode active materials (for example, cobalt lithium oxide, nickel lithium oxide, lithium iron phosphate, etc.) and negative electrode active materials (for example, carbon materials, tin-based negative electrode materials, etc.) in the market may be selected, and those skilled in the art can select according to the actual working condition requirements.

Preferably, in this embodiment, the first pole piece 1 is made of aluminum foil, and the second pole piece 2 is made of copper foil, so as to ensure the safety of the first pole piece 1 and the second pole piece 2 during use, and effectively ensure good electrical conductivity of the first pole piece 1 and the second pole piece 2.

Preferably, in the present embodiment, since the length of the first pole piece 1 is long in the first direction, in order to simultaneously satisfy the purpose of saving active materials, as shown in fig. 1 to 2, the first active material 13 is coated on the first coating region 11 in a spaced coating manner; since the length of the second pole piece 2 is shorter in the first direction, the second active material 23 is coated on the second coating region 21 in a continuous coating manner, so that tailing can be prevented, and the dimensional accuracy of the second pole piece 2 is ensured.

Alternatively, the interlayer member 3 is a separator having gel-state electrolyte 31 or liquid-state electrolyte on opposite surfaces of the separator. Preferably, in the present embodiment, the electrolyte is gel electrolyte 31, so as to meet the requirements of higher conductivity stability and conductivity under practical conditions.

Further, in this embodiment, as shown in fig. 3, the gel electrolyte 31 is disposed on the separator in a lattice manner, so that the usage amount of the gel electrolyte 31 can be reduced under the condition that the first pole piece 1 and the second pole piece 2 are electrically connected through the gel electrolyte 31, thereby further reducing the production cost; and also can improve the stability and the use safety of the gel state electrolyte 31 on the separator, prolonging the service life of the wound battery. It will be appreciated that the distance between two adjacent gel electrolytes 31 can be adjusted according to practical production requirements, which is not particularly limited in the present utility model.

In some parallel embodiments, the electrolyte may be a liquid electrolyte, and in the process of manufacturing a rolled battery containing the liquid electrolyte, unlike the process of manufacturing a rolled battery containing the gel electrolyte 31, the tab (which may be a positive tab or a negative tab) at one end needs to be flattened to form a compact surface, and then the liquid electrolyte is injected into the rolled battery; after the injection is completed, the tab at the other end is flattened to form another dense surface, so that the liquid electrolyte can be prevented from leaking out from both ends of the wound battery.

It will of course be appreciated that in some juxtaposed embodiments, the above-described sandwich element 3 may also be formed by coating a solid electrolyte layer on the first active material 13 and/or on the second active material 23, taking advantage of the properties of the solid electrolyte layer so that it may act as a separator; in addition, the production requirements of the coiled battery cell on better safety and higher energy density under the actual working condition can be met. Further, the solid electrolyte layer is coated only on the first active material 13 or the second active material 23, and the separation distance between the first and second electrode sheets 1 and 2 can be shortened as compared with the case where the solid electrolyte layer is coated on both the first and second active materials 13 and 23, which is advantageous for further improving the mass energy density of the wound battery.

Further, when the wound battery is wound, the edge of the second coating region 21 along the first direction protrudes from the interlayer member 3, so that a portion of the second active material 23 on the second coating region 21 may be in direct contact with the first active material 13 on the first coating region 11, thereby causing a short circuit of the wound battery, and thus affecting the safety of the wound battery. Therefore, in this embodiment, in order to avoid the occurrence of the short circuit of the battery cell, as shown in fig. 1, at least part of the interlayer member 3 extends out of the second coating region 21 along the first direction, so that after the winding is completed, the wound battery is terminated by the terminated empty foil region 14 at the outermost ring, the sub-outer ring is terminated by the interlayer member 3, and the innermost ring is terminated by the second coating region 21, and the second coating region 21 is completely covered and surrounded by the interlayer member 3, so that the direct contact of the first active material 13 and the second active material 23 can be fundamentally avoided, and the service life of the wound battery is improved.

Optionally, as shown in fig. 1, two ends of the interlayer member 3 extend out of the first coating area 11 and the second coating area 21 respectively along the second direction, so that the phenomenon that the anode tab after being flattened is reversely inserted into the winding battery to cause short circuit can not occur due to the blocking of the interlayer member 3 in the second direction, and the phenomenon that the cathode tab after being flattened is reversely inserted into and directly contacts with the second active material 23 on the anode tab can not occur, thereby effectively improving the use safety of the winding battery. Preferably, in the present embodiment, the length of the interlayer 3 extending from the second coating area 21 along the second direction ranges from 0.5mm to 2mm, so that the winding type battery cell can adjust the length of the interlayer 3 extending from the second coating area 21 according to the actual requirement, so as to ensure that the positive electrode tab is not in direct contact with the second active material 23.

Optionally, the wound battery further comprises an insulating seal (not shown in the figures) covering the tail of the tail-out hollow foil region 14 to seal the wound battery to further ensure tightness and use safety of the wound battery. The insulating sealing piece can be insulating adhesive paper or insulating adhesive tape, or insulating sealing glue formed after glue solution is solidified. For example, when the insulating sealing member is made of insulating adhesive paper or insulating adhesive tape, wrapping and winding at least one circle of insulating sealing member on the outer ring of the coiled battery, and reserving the surfaces of the positive and negative full tabs at two ends of the coiled battery for the subsequent welding process of the battery module, so that a better sealing effect can be formed in the ending empty foil region 14; when the insulating sealing member adopts insulating sealant, the protective films are firstly stuck on the surfaces of the positive electrode lug and the negative electrode lug, then the winding type battery is immersed in the insulating sealant, the winding type battery is taken out after being immersed for a period of time and dried, at the moment, a layer of insulating sealant is attached on the outer surface of the winding type battery, so that a good sealing effect is achieved in the area of the ending empty foil area 14, and finally the protective films on the surfaces of the positive electrode lug and the negative electrode lug are removed. Accordingly, one skilled in the art can choose the material for the insulating seal based on the cost of purchase and the actual circumstances of the manufacturing process.

It is emphasized that the insulating seal is small and lightweight and therefore does not significantly affect the mass and volumetric energy densities of the wound cell.

In order to facilitate understanding, the production and manufacturing process of the wound battery in this embodiment will be described in detail.

S1, preparing a first pole piece 1 by using aluminum materials, coating slurry of a first active material 13 on a first coating area 11 in an intermittent coating mode, and arranging a tail-ending empty foil area 14 at the winding tail end of the first pole piece 1;

s2, preparing a second pole piece 2 by using a copper material, wherein the slurry of a second active material 23 is coated on a second coating area 21 in a continuous coating mode;

s3, preparing a diaphragm by adopting any one material such as polypropylene, polyethylene, polyimide or non-woven fabric, and injecting gel electrolyte 31 on two opposite surfaces of the diaphragm in a lattice arrangement, so as to form an interlayer piece 3;

s4, arranging the interlayer components 3 in a manner of being clamped between the first pole piece 1 and the second pole piece 2, wherein the first empty foil region 12 and the second empty foil region 22 extend towards two opposite ends along the second direction respectively;

s5, after the first pole piece 1, the interlayer piece 3 and the second pole piece 2 are wound in the first direction, ending the ending empty foil area 14 on the first pole piece 1;

s6, performing hot-press shaping on the wound cylindrical battery to form a required square wound battery, and removing wrinkles in a battery core formed by winding through hot-press shaping to improve the flatness of the wound battery;

s7, respectively flattening the first hollow foil area 12 and the second hollow foil area 22 inwards through a flattening treatment process so as to respectively form a positive compact surface and a negative compact surface at two ends of the coiled battery;

and S8, performing insulation sealing treatment on the ending empty foil region 14 by using an insulation sealing member.

Example two

Unlike the first embodiment, in this embodiment, the first electrode sheet 1 is a negative electrode sheet, the second electrode sheet 2 is a positive electrode sheet, the first active material 13 is a negative electrode active material, the second active material 23 is a positive electrode active material, and the ending hollow foil region 14 is disposed at the winding tail end of the negative electrode sheet, that is, the outermost ring of the winding battery is the negative electrode sheet, the second outer ring is the interlayer member 3, and the innermost ring is the positive electrode sheet, and the purpose of extending the ending region of the winding battery can also be achieved by disposing the ending hollow foil region 14 on the negative electrode sheet. Therefore, those skilled in the art can choose whether the ending empty foil region 14 is disposed on the positive plate or the negative plate according to the actual working condition requirement, which is not particularly limited in the present utility model.

Accordingly, the two ends of the interlayer part 3 extend out of the first coating area 11 and the second coating area 21 respectively, so that the phenomenon of short circuit in the reverse-inserted winding type battery can not occur to the flattened positive electrode lug, and the phenomenon that the flattened negative electrode lug is reversely inserted and directly contacted with the positive electrode active material on the positive electrode plate can not occur, thereby effectively improving the use safety of the winding type battery. Preferably, in the present embodiment, along the second direction, the length of the interlayer 3 extending from the second coating area 21 ranges from 0.5mm to 2mm, so that the length of the wound battery extending from the interlayer 3 extending from the second coating area 21 can be adjusted according to actual needs, so as to ensure that the negative electrode tab is not in direct contact with the positive electrode active material on the positive electrode sheet.

It is to be understood that the above examples of the present utility model are provided for clarity of illustration only and are not limiting of the embodiments of the present utility model. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. Any modification, equivalent replacement, improvement, etc. which come within the spirit and principles of the utility model are desired to be protected by the following claims.

Claims

1. The winding type battery comprises a first pole piece (1), a second pole piece (2) and an interlayer piece (3), and is characterized in that:

the first pole piece (1) comprises a first coating area (11) and a first empty foil area (12), the first coating area (11) is used for coating a first active material (13), the first pole piece (1) is provided with a tail empty foil area (14) along a first direction, and the tail empty foil area (14) can be attached to the tail end of the winding battery in a sealing mode;

the second electrode sheet (2) comprises a second coating area (21) and a second empty foil area (22), the second coating area (21) is used for coating a second active material (23), the first coating area (11), the interlayer piece (3) and the second coating area (21) are sequentially attached to each other and wound into the wound battery along the first direction, the first empty foil area (12) and the second empty foil area (22) respectively extend out to the opposite ends of the wound battery along the second direction to form a positive electrode lug and a negative electrode lug, and a positive compact surface and a negative compact surface are respectively formed through flattening, so that the positive compact surface and the negative compact surface are covered on the two ends of the wound battery in a sealing mode, and the first direction is horizontal and perpendicular to the second direction;

the interlayer piece (3) can enable the first pole piece (1) and the second pole piece (2) to be connected in a conductive mode.

2. The wound battery according to claim 1, characterized in that the first active material (13) is coated with a solid electrolyte layer, which is the sandwich element (3);

and/or the second active material (23) is coated with the solid electrolyte layer.

3. The wound battery according to claim 1, characterized in that the interlayer (3) is a separator, the opposite surfaces of which have a gel-state electrolyte (31) or a liquid electrolyte.

4. A wound battery according to claim 3, wherein the opposite surfaces of the separator are filled with the gel state electrolyte (31), the gel state electrolyte (31) being arranged in a lattice.

5. A wound battery according to any one of claims 1-4, characterized in that in the second direction both ends of the sandwich element (3) protrude from the first (11) and the second (21) application zone, respectively.

6. A wound battery according to claim 5, characterized in that the length of the sandwich element (3) extending beyond the second application zone (21) in the second direction ranges from 0.5mm to 2mm.

7. A wound battery according to claim 1, characterized in that at least part of the interlayer member (3) protrudes from the second coating zone (21) in the first direction.

8. The wound battery according to claim 1, further comprising an insulating seal covering the ending empty foil region (14).

9. The wound battery according to claim 1, characterized in that the first active material (13) is applied to the first application zone (11) by intermittent coating and the second active material (23) is applied to the second application zone (21) by continuous coating.

10. The wound battery according to claim 1, wherein one of the first and second pole pieces (1, 2) is an aluminum foil and the other is a copper foil.