CN214588941U

CN214588941U - Composite pole piece and battery

Info

Publication number: CN214588941U
Application number: CN202120259490.2U
Authority: CN
Inventors: 鲁树立; 张进; 罗扬青; 王庆祎
Original assignee: SHENZHEN GREENSUN TECHNOLOGY CO LTD
Current assignee: Shenzhen Greensheng Technology Co ltd
Priority date: 2021-01-29
Filing date: 2021-01-29
Publication date: 2021-11-02
Anticipated expiration: 2031-01-29

Abstract

The utility model relates to a compound pole piece and battery, this compound pole piece include a diaphragm and a pole piece at least, and pole piece and the range upon range of setting of diaphragm are provided with two joining regions along its length direction interval on the pole piece, and at least one joining region is located the length direction's of pole piece tip, and the pole piece is connected fixedly with the diaphragm in joining region department. The connection areas at the two ends of the pole piece are fixedly connected with the diaphragm, so that the connection between the pole piece and the diaphragm is realized, the reduction of the bonding surface between the pole piece and the diaphragm is facilitated, the using amount of glue solution is reduced, the overflow of the glue solution is avoided, the infiltration time of electrolyte is shortened, and the production efficiency is improved.

Description

Composite pole piece and battery

Technical Field

The utility model relates to a battery production technical field especially relates to a compound pole piece and contain battery of this compound pole piece.

Background

The existing pole piece and diaphragm compounding process is a bag making process and a diaphragm adhesive compounding pole piece process respectively. The bag making process mainly aligns the upper and lower surfaces of the positive plate with the diaphragm, makes the positive plate bag after hot pressing the positive plate and the diaphragm for four weeks, and then repeatedly and alternately laminates the positive plate bag and the negative plate to form the battery core. The battery core has the problem of dislocation of positive and negative pole pieces, and the quality of the battery core is influenced. The diaphragm tape glue composite pole piece has high process cost requirement, and the whole diaphragm is coated with more glue, so that the glue easily overflows the diaphragm, and further the adverse effect is caused to the battery core. Meanwhile, liquid injection is carried out after the battery core is formed by laminating the composite pole pieces, and the soaking time is long after the electrolyte is injected into the battery core due to the fact that the diaphragm and the pole pieces are bonded together, so that the production efficiency is low.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a compound pole piece and battery, it annotates liquid infiltration time weak point, and production efficiency is high.

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

the provided composite pole piece at least comprises a diaphragm and a pole piece, wherein the pole piece and the diaphragm are arranged in a laminated mode, two connecting areas are arranged on the pole piece at intervals along the length direction of the pole piece, at least one connecting area is located at the end portion of the pole piece in the length direction, and the pole piece is fixedly connected with the diaphragm at the connecting areas.

Further, one end of the pole piece forms a pole lug, wherein a part of the pole lug extends to the outside of the diaphragm, and the rest part of the pole lug is positioned in the inside of the diaphragm and forms the connecting area.

Further, one of the connection areas is located at one end of the pole piece facing away from the pole lug, and the connection area does not extend beyond the edge of the diaphragm.

Further, the pole piece is bonded to the diaphragm at the connection region.

Furthermore, the diaphragm is provided with a first side face and a second side face which are opposite, the number of the pole pieces is two, the two pole pieces are respectively a positive pole piece and a negative pole piece, the positive pole piece and the negative pole piece are respectively arranged on the first side face and the second side face, and the positive pole piece and the negative pole piece are just arranged.

Further, the size of the positive plate is smaller than that of the negative plate.

Furthermore, the number of the positive plates is multiple, the positive plates are arranged at intervals along the length direction of the diaphragm, and the negative plates correspond to the positive plates one by one.

Furthermore, the number of the diaphragms is two, and the two diaphragms are arranged at intervals;

the positive plate is clamped between the two diaphragms; or, the negative electrode sheet is clamped between the two separators.

Also provides a battery, which comprises the composite pole piece.

The utility model discloses compare in prior art's beneficial effect:

the utility model discloses a compound pole piece and battery is connected fixedly with the diaphragm through the joining region that is located pole piece body both ends, realizes being connected of pole piece and diaphragm, is favorable to reducing the bonding face between pole piece and the diaphragm, reduces the glue solution quantity, and then avoids the glue solution to spill over and reduce the infiltration time of electrolyte, improves production efficiency.

Drawings

Fig. 1 is a schematic diagram of a composite pole piece of an embodiment.

FIG. 2 is a cross-sectional view of a composite pole piece of an embodiment.

FIG. 3 is a cross-sectional view of another embodiment of a composite pole piece.

Fig. 4 is a cross-sectional view of a cell of an embodiment.

Fig. 5 is a cross-sectional view of a cell of another embodiment.

In the figure:

1. pole pieces; 11. a first connection region; 12. a second attachment zone; 13. a tab; 14. a positive plate; 15. a negative plate; 2. a diaphragm; 3. a pole piece assembly.

Detailed Description

In order to make the technical problem solved by the present invention, the technical solution adopted by the present invention and the technical effect achieved by the present invention clearer, the technical solution of the present invention will be further explained by combining the drawings and by means of the specific implementation manner.

Referring to fig. 1 to 3, the utility model provides a composite pole piece includes a diaphragm 2 and a pole piece 1 at least, and pole piece 1 is range upon range of setting with diaphragm 2, and pole piece 1 is last to be provided with two joining regions along its length direction interval, and one of them joining region is located pole piece 1's length direction's tip, and pole piece 1 is connected fixedly with diaphragm 2 in joining region department. It is understood that the pole piece 1 may be a positive pole piece 14 or a negative pole piece 15, the cell includes a plurality of positive pole pieces 14 and a plurality of negative pole pieces 15, the positive pole pieces 14 and the negative pole pieces 15 are alternately arranged, so that one negative pole piece 15 is arranged between two adjacent positive pole pieces 14, or one positive pole piece 14 is arranged between two adjacent negative pole pieces 15, and meanwhile, the adjacent positive pole pieces 14 and the adjacent negative pole pieces 15 are separated by the diaphragm 2. The manufacturing of the battery cell comprises a lamination mode and a winding mode, when the lamination is manufactured, a plurality of positive plates 14, negative plates 15 and the diaphragm 2 are laminated together in a set sequence, then the tabs 13 on all the positive plates 14 are welded together to form positive lugs, and the tabs 13 on all the negative plates 15 are welded together to form negative lugs, so that the manufacturing of the lamination battery cell is realized; during winding, at least one positive plate 14, at least one negative plate 15 and the diaphragm 2 are stacked together in a set order, then the winding is cylindrical or elliptic cylindrical, all the tabs 13 on the positive plates 14 are welded together to form positive tabs, all the tabs 13 on the negative plates 15 are welded together to form negative tabs, and the winding battery core is manufactured. In order to facilitate the lamination operation or the winding operation, the diaphragm 2 is arranged on the surface of the pole piece 1 to form a composite pole piece, so that the lamination or winding operation efficiency is improved. In this embodiment, the pole piece 1 and the diaphragm 2 may be combined together by spraying, inkjet printing, dispensing, screen printing, laser printing, or welding to form a composite pole piece. Preferably, the pole piece 1 and the diaphragm 2 are bonded together in a dispensing manner. The separator 2 is generally a polyolefin porous film having a high strength and a reduced thickness of 20 to 40 μm. The pole piece 1 is adhered to the side surface of the diaphragm 2 and is fixed through glue solution. Two connecting areas are arranged in the length direction of the pole piece 1 and are used for being connected and fixed with the diaphragm 2. The width direction of the connecting area is the same as the length direction of the pole piece 1, the width dimension of the connecting area is smaller than 1/3 of the length dimension of the pole piece 1, and glue is arranged in the connecting area, so that the connecting area is bonded with the diaphragm 2 through the glue, and the connection and fixation of the pole piece 1 and the diaphragm 2 are realized. The structure reduces the adhesive surface between the pole piece 1 and the diaphragm 2, thereby reducing the dosage of glue solution and being beneficial to avoiding the influence of the overflow of the glue solution on the performance of the battery cell. One of the connecting areas is located at the end part of the pole piece 1, so that electrolyte can be favorably infiltrated to the middle part of the pole piece 1 along the end part corresponding to the connecting area in the electrolyte injection operation, the infiltration time of the battery electrolyte injection is reduced, and the production efficiency is improved.

The longitudinal direction of the separator 2 is the X direction in the figure, and the longitudinal direction of the pole piece 1 is the Y direction in the figure.

In particular, one end of the pole piece 1 forms a tab 13, wherein part of the tab 13 extends outside the separator 2 and the remaining part of the tab 13 is located inside the separator 2 and forms a connection zone. It will be understood that the outer portion of the membrane 2 refers to the area on the plane of the side of the membrane 2 that is outside the edge area of the membrane 2. It is also understood that the orthographic projection of part of the tab 13 on the separator 2 is outside the separator 2. In this embodiment, one end of the pole piece 1 is cut to form the tab 13, so that the pole piece 1 includes a pole piece body and the tab 13 located at one end of the pole piece body, and the width (shown in the X direction) of the tab 13 is smaller than the width of the pole piece body. One end of the lug 13 departing from the pole piece body is located outside the diaphragm 2, one end of the lug 13 close to the pole piece body is located inside the diaphragm 2, the lug 13 located inside the diaphragm 2 is made to form a connection area, and the lug 13 can be fixedly connected with the diaphragm 2 through the connection area.

In particular, one of the connection zones is located at the end of the pole piece 1 facing away from the tab 13 and does not project beyond the edge of the diaphragm 2. It is understood that the two connection areas are a first connection area 11 and a second connection area 12, respectively, the first connection area 11 being located at the end of the pole piece 1 facing away from the tab 13, and the second connection area 12 being located at the end of the tab 13 close to the pole piece body. The second connection region 12 is located at the edge of the membrane 2, the first connection region 11 is spaced apart from the edge of the membrane 2, and the orthographic projection of the first connection region 11 on the membrane 2 is located inside the membrane 2. The separator 2 functions to space the positive electrode sheet 14 and the negative electrode sheet 15, and thus, to space the first connection region 11 from the edge of the separator 2, so as to prevent the first connection region 11 from extending to the outside of the separator 2 during the lamination operation or the winding operation, thereby preventing the positive electrode sheet 14 and the negative electrode sheet 15 from being brought into contact.

Specifically, when the pole piece 1 and the diaphragm 2 are bonded, the glue dispensing position of the connecting area is located in the non-edge area of the connecting area, so that glue solution is prevented from overflowing along the edge of the connecting area.

In one embodiment, referring to fig. 2, the composite pole piece includes a diaphragm 2 and two pole pieces 1 respectively disposed on two opposite sides of the diaphragm 2, where the two pole pieces 1 are a positive pole piece 14 and a negative pole piece 15, the diaphragm 2 has a first side and a second side opposite to each other, the positive pole piece 14 is disposed on the first side, the negative pole piece 15 is disposed on the second side, and the positive pole piece 14 and the negative pole piece 15 are disposed opposite to each other, so that a center of the positive pole piece 14 coincides with a center of the negative pole piece 15. Meanwhile, the size of the positive plate 14 is smaller than that of the negative plate 15, so that the charge and discharge performance of the battery cell is improved. This structure sets up positive plate 14 and negative pole piece 15 in the both sides of same diaphragm 2 in order to form compound pole piece through simultaneously, when lamination operation or coiling operation, only needs carry out corresponding range upon range of or convolute to a plurality of compound pole pieces, avoids the operation in-process to adjust the order between well, negative pole piece and diaphragm 2 three and arranges in order, can further improve production efficiency.

Specifically, to facilitate folding of the composite pole piece to form the cell, the composite pole piece includes a separator 2 and a plurality of positive pole pieces 14 disposed on a first side of the separator 2, and a plurality of negative pole pieces 15 disposed on a second side of the separator 2. The positive plates 14 are arranged at intervals along the length direction of the first side face of the diaphragm 2, the positive plates 14 and the negative plates 15 are arranged in a one-to-one correspondence mode, the negative plates 15 are arranged at intervals along the length direction of the second side face of the diaphragm 2, the positive plates 14 and the negative plates 15 are identical in number, and the positive plates 14 are opposite to the corresponding negative plates 15. Of course, the specific number of the positive plates 14 and the negative plates 15 is adaptively selected according to the number of the pole pieces 1 required by the cell.

The composite pole piece of the embodiment can be formed into a battery cell in a lamination mode or a winding mode. Preferably, referring to fig. 5, the composite pole piece is folded back and forth in a "Z" shape along its length direction, and a plurality of positive pole pieces 14 and a plurality of negative pole pieces 15 are laminated together along a first direction, and one negative pole piece 15 is arranged between two adjacent positive pole pieces 14. The first direction is perpendicular to the positive electrode tab 14 or the negative electrode tab 15. The specific method comprises the following steps: along the length direction of the composite pole piece, the pole piece 1 is not arranged on the diaphragm 2 at one end of the composite pole piece to form a diaphragm blank section, the diaphragm blank section is folded to the negative pole piece 15 to cover the negative pole piece 15, and then the positive pole piece 14 and the negative pole piece 15 at one end of the composite pole piece are fixed on the platform. The corresponding positive plate 14 and the negative plate 15 form a small group of pole pieces, the small group of pole pieces is sequentially clamped by a manipulator to be turned over to the platform, and the small group of pole pieces on the platform are laminated together to form the battery cell. The mode can realize quick lamination and has the characteristic of high production efficiency.

In another embodiment, referring to fig. 3 and 4, the composite pole piece includes two diaphragms 2, and the two diaphragms 2 are arranged at intervals; the positive electrode sheet 14 is sandwiched between the two separators 2; alternatively, the negative electrode sheet 15 is sandwiched between the two separators 2. In this embodiment, the plurality of positive plates 14 and the plurality of negative plates 15 are respectively located on two sides of one of the diaphragms 2, the positive plates 14 and the negative plates 15 are arranged in a one-to-one correspondence manner, and each positive plate 14 is arranged opposite to the corresponding negative plate 15. The other separator 2 is located on the side of the negative electrode tab 15 facing away from the positive electrode tab 14 so that the negative electrode tab 15 is sandwiched between the two separators 2. For the lamination operation, the composite pole piece can be cut, and the cutting position is located between two adjacent positive pole pieces 14 or two adjacent negative pole pieces 15 to form the pole piece assembly 3, and the pole piece assembly 3 comprises one positive pole piece 14, one negative pole piece 15 and two diaphragms 2, and the positive pole piece 14, the diaphragms 2, the negative pole piece 15 and the diaphragms 2 are sequentially laminated together in the order of the second direction. The second direction is perpendicular to the positive electrode tab 14 or the negative electrode tab 15. Of course, in other embodiments, the negative electrode sheet 15, the separator 2, the positive electrode sheet 14, and the separator 2 may be stacked in this order. In the lamination operation, a plurality of pole piece assemblies 3 are laminated together in the second direction to form a cell. The method has high lamination speed, and is not used for independently finishing the sequence of the positive and negative plates in the lamination process, thereby being beneficial to improving the production efficiency.

In still another embodiment, referring to fig. 3, the composite electrode sheet includes two separators 2, the two separators 2 are disposed at an interval, and the positive electrode sheet 14 is sandwiched between the two separators 2, or the negative electrode sheet 15 is sandwiched between the two separators 2. Along the length direction of the separator 2, the gap between two adjacent positive electrode sheets 14 can accommodate one positive electrode sheet 14 or negative electrode sheet 15, and the gap between two adjacent negative electrode sheets 15 can accommodate one positive electrode sheet 14 or negative electrode sheet 15. In this embodiment, the plurality of positive plates 14 and the plurality of negative plates 15 are respectively located on two sides of one of the diaphragms 2, the positive plates 14 and the negative plates 15 are arranged in a one-to-one correspondence manner, and each positive plate 14 is arranged opposite to the corresponding negative plate 15. The other separator 2 is located on the side of the negative electrode tab 15 facing away from the positive electrode tab 14 so that the negative electrode tab 15 is sandwiched between the two separators 2. The separator 2 between two adjacent positive electrode sheets 14 or two adjacent negative electrode sheets 15 has a blank section that can cover a side of the positive electrode sheet 14 facing away from the separator 2. During lamination operation, the pole piece assembly 3 positioned at one end of the composite pole piece is fixed on the platform along the length direction of the composite pole piece, and then the pole piece assembly 3 is bent to the platform in a Z-shaped reciprocating manner in sequence through the manipulator and is connected with the pole piece assembly 3 positioned on the platform, so that a battery cell which is smoothly laminated together is formed. The mode lamination is fast, and is efficient.

The beneficial effect of this embodiment does: this composite pole piece is connected fixedly with diaphragm 2 through the joining region that is located pole piece 1 both ends, realizes being connected of pole piece 1 and diaphragm 2, is favorable to reducing the bonding surface between pole piece 1 and the diaphragm 2, reduces the glue solution quantity, and then avoids the glue solution to spill over and reduces the infiltration time of electrolyte, improves production efficiency.

Also provides a battery, which comprises the composite pole piece and a shell. The shell is provided with a containing cavity for containing the battery core and electrolyte, the composite pole pieces form the battery core in a laminated mode, a plurality of positive pole pieces 14 and a plurality of negative pole pieces 15 are laminated together in an interlaced mode, one negative pole piece 15 is arranged between every two adjacent positive pole pieces 14, or one positive pole piece 14 is arranged between every two adjacent negative pole pieces 15, and the adjacent positive pole pieces 14 and the adjacent negative pole pieces 15 are separated through the diaphragm 2. The electric core is installed and is held the intracavity to holding the intracavity and pouring into electrolyte, electrolyte and electric core are fully soaked, in order to guarantee the electrochemical reaction of electric core. Be provided with anodal post and negative pole post on the shell, anodal post is connected with the anodal ear on the electricity core, and the negative pole post is connected with the negative pole ear on the electricity core. According to the battery, the pole piece 1 is bonded with the diaphragm 2 through the connecting piece, so that the bonding surface between the pole piece 1 and the diaphragm 2 is reduced, the electrolyte infiltration time is reduced, and the production efficiency is improved.

The above description is only for the preferred embodiment of the present invention, and for those skilled in the art, there are variations on the detailed description and the application scope according to the idea of the present invention, and the content of the description should not be construed as a limitation to the present invention.

Claims

1. A composite pole piece is characterized by at least comprising a diaphragm and a pole piece, wherein the pole piece and the diaphragm are arranged in a laminated mode, two connecting areas are arranged on the pole piece at intervals along the length direction of the pole piece, one of the connecting areas is located at the end portion of the pole piece in the length direction, and the pole piece is fixedly connected with the diaphragm at the connecting areas.

2. The composite pole piece of claim 1 wherein one end of the pole piece forms a tab, wherein a portion of the tab extends to the exterior of the separator and the remaining portion of the tab is located on the interior of the separator and forms the connection region.

3. The composite pole piece of claim 2 wherein one of the connection areas is located at the end of the pole piece facing away from the tab and the connection area does not extend beyond the edge of the separator.

4. The composite pole piece of claim 1 wherein said pole piece is bonded to said membrane at said connection area.

5. The composite pole piece of claim 1, wherein said separator has a first side and a second side opposite to each other, said two pole pieces are a positive pole piece and a negative pole piece, said positive pole piece and said negative pole piece are respectively disposed on said first side and said second side, and said positive pole piece and said negative pole piece are oppositely disposed.

6. The composite pole piece of claim 5, wherein the size of the positive pole piece is smaller than the size of the negative pole piece.

7. The composite pole piece according to claim 5, wherein the number of the positive pole pieces is plural, the plural positive pole pieces are arranged at intervals along the length direction of the separator, and the negative pole pieces correspond to the positive pole pieces one by one.

8. The composite pole piece of claim 7, wherein there are two said membranes, two said membranes being spaced apart;

9. The composite pole piece of claim 7, wherein along the length direction of the separator, the gap between two adjacent positive pole pieces can accommodate one positive pole piece or negative pole piece, and the gap between two adjacent negative pole pieces can accommodate one positive pole piece or negative pole piece.

10. A battery comprising the composite pole piece of any one of claims 1 to 9.