CN114551963A

CN114551963A - Roll up core and battery

Info

Publication number: CN114551963A
Application number: CN202210031401.8A
Authority: CN
Inventors: 黄海宁
Original assignee: Shanghai Lanjun New Energy Technology Co Ltd
Current assignee: Shanghai Lanjun New Energy Technology Co Ltd
Priority date: 2022-01-12
Filing date: 2022-01-12
Publication date: 2022-05-27

Abstract

The invention relates to a winding core and a battery, wherein the winding core comprises a first positive plate, a negative plate and a diaphragm which are wound together, the diaphragm separates the first positive plate from the negative plate, the first positive plate and the negative plate are both connected with lugs, the winding core is characterized in that the first positive plate and the negative plate are both coated with coatings, the negative plate completely covers the first positive plate, the winding core also comprises a second positive plate coated with coatings on both sides, the second positive plate is connected with the lugs and corresponds to the innermost circle of the negative plate, the winding core also comprises a third positive plate coated with coatings on one side, and the third positive plate is connected with the lugs and corresponds to the outermost circle of the negative plate. Compared with the prior art, the invention improves the flexibility of the design of the winding core and the whole energy density of the battery core, reduces the waste of the active material of the negative plate in the winding core, and improves the energy density and the safety of the battery.

Description

Roll up core and battery

Technical Field

The invention relates to the technical field of battery design and manufacture, in particular to a winding core and a battery.

Background

As shown in fig. 1, in order to completely coat the cathode plate with the anode plate, the number of layers of the cathode plate and the anode plate is generally designed to be an even number in the conventional winding core design, the number of layers of the cathode plate is generally 2 more than that of the anode plate, and both surfaces of the cathode plate and the anode plate are coated with coatings. For example, the number of layers of the positive electrode sheet is 2N, and the number of layers of the negative electrode sheet is 2N +2, in this case, however, the negative electrode sheets (without the region facing the positive electrode) on the inner and outer rings thereof always have unused material regions, the negative electrode needs to be fed first because the negative electrode is required to cover the positive electrode in the innermost ring, and for the continuously coated electrode sheets, the negative electrode material layers with two unused surfaces are generated in the innermost ring of the negative electrode. Resulting in waste of the anode material. Especially, when the roll core design with a long roll core length and a large number of roll cores is adopted, the waste of the cathode material is large.

In addition, for the structural design of the conventional cathode sheet ending and coating the anode, the outside of the roll core is ended by the cathode and is in a low potential state. For the structural design of the charged shell, for example, the external diaphragm or the insulating sheet of the winding core is easy to generate short circuit between the shell and the winding core under extreme conditions, such as breakage and package leakage, and the safety of the battery is reduced. For the structural design with uncharged shell, the potential state of the external part of the winding core is low, and similarly, the situation of shell corrosion is easily generated under the extreme conditions of a diaphragm or an insulating sheet outside the winding core, such as breakage and package leakage, and the electrochemical corrosion phenomenon is a common failure case in the uncharged design of the shell of the aluminum shell at present.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide a winding core and a battery, so that the flexibility of the design of the winding core and the overall energy density of the battery core are improved, and the waste of active materials of a negative plate in the winding core is reduced.

The purpose of the invention can be realized by the following technical scheme:

the utility model provides a roll up core, is including convoluteing first positive plate, negative pole piece and the diaphragm together, the diaphragm separate first positive plate and negative pole piece, first positive plate and negative pole piece on all be connected with utmost point ear, first positive plate and the equal two-sided coating of negative pole piece have the coating, the negative pole piece cover first positive plate completely, roll up the core and still include the second positive plate of two-sided coating, the second positive plate be connected with utmost point ear, and with negative pole piece inner circle phase-match.

Furthermore, the winding core also comprises a third positive plate, wherein a coating is coated on one side of the third positive plate and matched with the outermost ring of the negative plate.

Furthermore, the third positive plate is distributed on one side of the winding core.

Furthermore, the third positive plates are distributed on two opposite sides of the winding core.

Further, the casing is a non-charging casing, and the surface of the third positive plate, which is not coated with the coating, is provided with an insulating adhesive tape.

Furthermore, the shell is an electrified shell, and one side of the third positive plate, which is not coated with the coating, is exposed.

Further, the negative plate completely covers the second positive plate, and the distance between the end of the innermost ring of the negative plate and the end of the second positive plate is not less than 0.2 mm.

Further, the diaphragm completely covers the outermost ring of the negative plate.

A battery comprising a can and the winding core of any one of claims 1-8, the winding core being located within the can.

Further, the winding core further comprises a third positive plate, and the shell is an electrified shell or an uncharged shell.

Compared with the prior art, the invention has the following beneficial effects:

(1) the winding core comprises a first positive plate, a second positive plate, a negative plate and a diaphragm, wherein the first positive plate and the first positive plate are wound together, the first positive plate, the second positive plate and the negative plate are all designed into complete double-sided pole pieces, the pole is led out from a pole lug, the negative plate completely covers the first positive plate, and the second positive plate is matched with the innermost ring of the negative plate, so that the layer number setting of the positive plate and the negative plate is not limited by an even-numbered layer, the winding core is more flexible, the flexible design of the product capacity of a battery cell is facilitated, the waste of active materials of the negative plate in the winding core is reduced, and the integral energy density of the battery cell is improved;

(2) according to the invention, the single second positive plate with the double-sided coating is arranged on the inner ring, so that the probability of breaking the innermost ring of the positive plate can be reduced, and the reliability is improved;

(3) the distance between the end part of the innermost ring of the negative plate and the end part of the second positive plate is not less than 0.2mm, so that the innermost ring of the negative plate is ensured to completely cover the second positive plate;

(4) the shell is an uncharged shell, the surface of the third positive plate, which is not coated with the coating, is provided with the insulating adhesive tape, and the outer ring of the winding core is terminated by the insulating adhesive tape surface on the third positive plate and is matched with the uncharged shell, so that the risk of corrosion of the shell is reduced;

(5) the shell is an electrified shell, one side of the third positive plate, which is not coated with the coating, is exposed, and the outer ring of the winding core is terminated by the exposed current collector of the third positive plate and is matched with the electrified shell, so that the short circuit risk is reduced.

Drawings

FIG. 1 is a schematic structural view of a conventional winding core;

FIG. 2 is a schematic view of the structure of a core in example 1;

FIG. 3 is a schematic view of the structure of a core in example 2;

fig. 4 is a schematic structural view of a core in example 3.

Detailed Description

The invention is described in detail below with reference to the figures and specific embodiments. The present embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation manner and a specific operation process are given, but the scope of the present invention is not limited to the following embodiments.

Example 1

A winding core, as shown in figure 2, comprises a first positive plate, a negative plate and a diaphragm which are wound together, wherein the diaphragm separates the first positive plate from the negative plate, the first positive plate and the negative plate are both connected with tabs, the first positive plate and the negative plate are both coated with coatings on both sides, the negative plate completely covers the first positive plate, the winding core also comprises a second positive plate coated with coatings on both sides, the second positive plate is connected with the tabs and is matched with the innermost ring of the negative plate, namely, the two opposite sides of the second positive plate are opposite to the inner side surface of the innermost ring of the negative plate;

the diaphragm completely covers the outermost ring of the negative plate.

The second positive plate is designed as a complete double-sided positive plate, a tab leading-out electrode is arranged on the second positive plate, and the second positive plate enters the inside of the winding core at a fixed position and corresponds to the innermost ring of the negative plate through program setting during winding feeding.

In order to ensure that the innermost circle of the negative pole piece completely covers the second positive pole piece, the distance between the end part of the innermost circle of the negative pole piece and the end part of the second positive pole piece is not less than 0.2 mm.

The number of piles of positive plate and negative pole piece sets up the restriction that does not receive the even number layer, and is comparatively nimble, and the nimble design of the electric core product capacity of being convenient for reduces the waste of the active material of rolling up the inside negative pole piece of core through the setting of second positive plate, promotes the whole energy density of electric core, sets up the second positive plate of monolithic double-sided coating at the inner circle simultaneously, can reduce the probability of the most inner circle pole piece rupture, promotes the reliability.

Example 2

In this embodiment, as shown in fig. 3, the winding core further includes a third positive plate, a single surface of the third positive plate is coated with a coating and is matched with an outermost ring of the negative plate, that is, the surface of the third positive plate coated with the coating is opposite to an outer side surface of the outermost ring of the negative plate, and the third positive plate is distributed on a single side of the winding core. The rest is the same as in example 1.

Example 3

In this embodiment, as shown in fig. 4, the third positive electrode sheets are disposed on opposite sides of the winding core, and the rest is the same as in embodiment 2.

Example 4

A battery comprises a shell and the winding core in embodiment 1, wherein the winding core is positioned in the shell.

The shell is an uncharged shell, and one side of the third positive plate, which is not coated with the coating, is provided with an insulating adhesive tape.

The insulating adhesive tape surface on the outer ring of the winding core is terminated by the third positive plate and is matched with the uncharged shell, so that the risk of corrosion of the shell is reduced.

Example 5

In this embodiment, the casing is electrified casing, and the one side of the uncoated coating of third positive plate is exposed, rolls up the core outer lane and ends with the naked mass flow body of third positive plate, matches with electrified casing, reduces the short circuit risk. The rest is the same as in example 4.

Embodiments 1, 2, 3, 4, and 5 provide a winding core and a battery, which improve the flexibility of the design of the winding core and the overall energy density of the battery core, reduce the waste of the active material of the negative plate inside the winding core, and meet the concept of cost reduction in design.

The foregoing detailed description of the preferred embodiments of the invention has been presented. It should be understood that numerous modifications and variations could be devised by those skilled in the art in light of the present teachings without departing from the inventive concepts. Therefore, the technical solutions available to those skilled in the art through logic analysis, reasoning and limited experiments based on the prior art according to the concept of the present invention should be within the scope of protection defined by the claims.

Claims

1. The utility model provides a roll up core, is including convoluteing first positive plate, negative pole piece and the diaphragm together, the diaphragm separate first positive plate and negative pole piece, first positive plate and negative pole piece on all be connected with utmost point ear, a serial communication port, the equal two-sided coating of first positive plate and negative pole piece have the coating, the negative pole piece cover first positive plate completely, roll up the core and still include the second positive plate of two-sided coating, the second positive plate be connected with utmost point ear, and with negative pole piece inner circle phase-match.

2. The winding core according to claim 1, characterized in that the winding core further comprises a third positive plate, and the third positive plate is coated on one side and matched with the outermost circle of the negative plate.

3. The winding core according to claim 2, wherein the third positive plate is distributed on one side of the winding core.

4. The winding core according to claim 2, wherein the third positive electrode plates are distributed on two opposite sides of the winding core.

5. The battery of claim 2, wherein said case is a non-charged case, and said third positive electrode tab has an insulating tape on a side thereof to which said coating layer is not applied.

6. The battery of claim 2, wherein said casing is a charged casing, and said uncoated side of said third positive electrode tab is exposed.

7. The winding core according to claim 1, characterized in that the negative pole piece completely covers the second positive pole piece, and the distance between the end of the innermost circle of the negative pole piece and the end of the second positive pole piece is not less than 0.2 mm.

8. The winding core according to claim 1, characterized in that the separator completely covers the outermost circle of the negative electrode sheet.

9. A battery comprising a can and the jellyroll of any of claims 1-8, said jellyroll being disposed within the can.

10. The battery of claim 7, wherein the winding core further comprises a third positive plate, and the housing is a charged housing or a non-charged housing.