CN102437378A

CN102437378A - Winding forming method of lithium ion battery

Info

Publication number: CN102437378A
Application number: CN201110447447XA
Authority: CN
Inventors: 苏文俊
Original assignee: GUANGDONG APOWER ELECTRONICS CO Ltd
Current assignee: GUANGDONG APOWER ELECTRONICS CO Ltd
Priority date: 2011-12-29
Filing date: 2011-12-29
Publication date: 2012-05-02

Abstract

The invention provides a winding forming method of a lithium ion battery. The method comprises the following steps of: preparing a positive pole piece and a negative pole piece; leaving an empty foil part at the middle of the positive pole piece; welding a negative pole ear at the tail end of the negative pole piece, and welding a positive pole ear at the middle empty foil part of the positive pole piece; folding the positive pole piece along middle empty foil part to form a first containing space; folding a membrane to form a second containing space; inserting the head end of the negative pole piece into the second containing space; turning over the head end of the negative pole piece to form a third containing space; inserting the turnover section of the negative pole piece into the first containing space, wherein the membrane separates the negative pole piece and the positive pole piece; and forming the positive and negative pole pieces to be a battery cell from the turnover section of the negative pole piece in a winding mode, wherein the positions of the positive and negative pole pieces have been determined. The positive pole ear is at the middle of the pole ear, which is contributed to transmitting electrons, and the internal resistance of the battery is reduced, therefore the cycle performance of batteries is improved; simultaneously, the length of the pole piece in winding is equivalent to 1/2 of the length of conventional pole piece, therefore the winding efficiency can be improved.

Description

A kind of lithium ion battery is wound into the type method

Technical field

The present invention relates to lithium ion battery, especially lithium ion battery is wound into the type method.

Background technology

At present, the lithium ion battery with very big application prospect of latest development, its maximum characteristics are to have characteristics such as volume is little, in light weight, safety non-pollution.But because along with the high speed of associated electronic device develops; Its performance requirement to lithium ion battery is also more and more harsher; The particularly further investigation of electric automobile recently and developing rapidly; Cycle life and high rate performance to lithium ion battery are had higher requirement, and the performance of lithium ion battery also needs further to promote at present.

Existing conventional winding method is the cathode pole piece that directly will be connected with negative lug, anode pole piece and the barrier film that the is connected with positive pole ear coiling and molding that superposes successively, and the internal resistance of cell of this coiling and molding is generally higher, and cycle life is undesirable.

In patent in the past; Publication number is the method for winding of the disclosed a kind of coiled secondary lithium ion battery of CN1929186; It has also solved the problems referred to above, but it has adopted the winding method of multipole ear, has increased the risk of lug rosin joint; And what its negative pole adopted is spaced manner, has increased the fussy degree of operation virtually.

Summary of the invention

Technical problem to be solved by this invention provides a kind of lithium ion battery and is wound into the type method, can effectively reduce the internal resistance of cell, and can effectively promote the cycle performance of battery; Simultaneously simple to operate, it is convenient to implement.

For solving the problems of the technologies described above, technical scheme of the present invention is: a kind of lithium ion battery is wound into the type method, may further comprise the steps:

(1), preparation anode pole piece and cathode pole piece, on anode pole piece, apply positive electrode active materials, on cathode pole piece, apply negative active core-shell material;

(2), reserve sky paper tinsel position in the middle of the anode pole piece;

(3), the end of cathode pole piece welds negative lug, the empty paper tinsel position welding positive pole ear in the centre of anode pole piece;

(4), empty paper tinsel position is folded to form first accommodation space along the centre with anode pole piece; Barrier film is folded to form second accommodation space, the cathode pole piece head end is inserted in second accommodation space, cathode pole piece and barrier film are become one;

Cathode pole piece that (5), will become one and barrier film turnover form the 3rd accommodation space;

(6), the lower end after the anode pole piece turnover is inserted in the 3rd accommodation space, barrier film separates cathode pole piece and anode pole piece;

(7), the inverted sections from cathode pole piece begins the position is confirmed that good positive and negative electrode pole piece carries out coiling and molding electricity core.

As improvement, said anode pole piece is provided with some positive pole ears, after the electric core winding moulding, said positive pole ear is compressed and welds together; State cathode pole piece and be provided with some negative lug, after the electric core winding moulding, said negative lug is compressed and welds together.

As improvement, the width of empty paper tinsel part is D in the middle of the said anode pole piece, and the positive pole ear width is D ₀, D>=2 D ₀

As improvement, when reeling beginning, the turnover end of the cathode pole piece that has become one and barrier film is placed on the coiler device, this is initiating terminal of coiling.

As improvement, said anode pole piece along the empty paper tinsel in centre partially folded after, be divided into the two sections pole piece, the hypomere pole piece is longer than the epimere pole piece, and said hypomere pole piece places in said the 3rd accommodation space.

The beneficial effect that the present invention is compared with prior art brought is:

Because anode ear is in the centre position of lug, helps the transmission of electronics, to lower the internal resistance of battery, thereby reach the purpose that promotes cycle performance of battery, the length of pole piece is equivalent to 1/2 of routine when reeling simultaneously, can improve the efficient of coiling.

Description of drawings

Fig. 1 launches sketch map for cathode pole piece.

Fig. 2 launches sketch map for anode pole piece.

Fig. 3 is the sketch map after the anode pole piece doubling.

Fig. 4 is anode pole piece and cathode pole piece fiting relation figure.

Fig. 5 is the sketch map behind anode pole piece, cathode pole piece, the barrier film coiling and molding.

Embodiment

Below in conjunction with Figure of description the present invention is described further.

(1), as shown in Figure 1, preparation anode pole piece 4 and cathode pole piece 1 apply positive electrode active materials on anode pole piece 4, on cathode pole piece 1, apply negative active core-shell material;

(2), like Fig. 2, shown in 3, the end of cathode pole piece 1 leaves the two-sided empty paper tinsel position 2 of certain width, reserves two-sided empty paper tinsel position 5 in the middle of the anode pole piece 4, the width of stating the empty paper tinsel position, centre 5 of anode pole piece 4 is D, the positive pole ear width is D ₀, D>=2 D ₀

(3), negative lug 3 are welded, the empty paper tinsel position 5 welding positive pole ears 6 in the centre of anode pole piece 4 in the terminal empty paper tinsel position 2 of cathode pole piece 1; After the welding of positive and negative electrode lug, need covering to be pasted at the solder joint position with adhesive tape;

(4), as shown in Figure 4, anode pole piece 4 is folded to form first accommodation space 7 along the centre position of empty paper tinsel position 5, the anode pole piece 4 after the doubling is divided into two sections pole piece 41,42, hypomere pole piece 42 is longer than epimere pole piece 41; Barrier film 10 is folded to form second accommodation space 8, cathode pole piece 1 head end is inserted in second accommodation space 8, cathode pole piece 1 and barrier film 10 are become one;

Cathode pole piece 1 that (5), will become one and the turnover of the centre position of barrier film 10 form the 3rd accommodation space 9;

(6), when reeling beginning, the turnover end of cathode pole piece that has become one 1 and barrier film 10 is placed on the coiler device;

(7), the inverted sections of cathode pole piece 1 11 is inserted in first accommodation space 7, the hypomere pole piece 42 of the anode pole piece 4 after the doubling inserts in the 3rd accommodation space 9, and barrier film 10 separates cathode pole piece 1 and anode pole piece 4;

(8), as shown in Figure 5, begin the position is confirmed that good positive and negative electrode pole piece carries out coiling and molding electricity core, uses adhesive tape that terminal position is fixed at last from the inverted sections 11 of cathode pole piece 1;

(9), then according to accomplishing follow-up dress box with the routine identical technology mode of reeling, fluid injection changes into, operations such as partial volume.

The present invention helps the transmission of electronics because anode ear is in the centre position of lug, lowers the internal resistance of battery, thereby reaches the purpose that promotes cycle performance of battery, and the length of pole piece is equivalent to 1/2 of routine when reeling simultaneously, can improve the efficient of coiling.

In order to make battery have better charge-discharge performance, said anode pole piece is provided with some positive pole ears, after the electric core winding moulding, said positive pole ear is compressed and welds together; State cathode pole piece 1 and be provided with some negative lug, after the electric core winding moulding, said negative lug is compressed and welds together.

Claims

1. a lithium ion battery is wound into the type method, it is characterized in that, may further comprise the steps:

(2), reserve sky paper tinsel position in the middle of the anode pole piece;

2. a kind of lithium ion battery according to claim 1 is wound into the type method, it is characterized in that: said anode pole piece is provided with some positive pole ears, after the electric core winding moulding, said positive pole ear is compressed and welds together; Said cathode pole piece is provided with some negative lug, after the electric core winding moulding, said negative lug is compressed and welds together.

3. a kind of lithium ion battery according to claim 1 is wound into the type method, it is characterized in that: the width of empty paper tinsel part is D in the middle of the said anode pole piece, and the positive pole ear width is D ₀, D>=2 D ₀

4. a kind of lithium ion battery according to claim 1 is wound into the type method, it is characterized in that: when reeling beginning, the turnover end of the cathode pole piece that has become one and barrier film is placed on the coiler device, this is initiating terminal of coiling.

5. a kind of lithium ion battery according to claim 1 is wound into the type method; It is characterized in that: said anode pole piece along the empty paper tinsel in centre partially folded after; Be divided into the two sections pole piece, the hypomere pole piece is longer than the epimere pole piece, and said hypomere pole piece places in said the 3rd accommodation space.