High-safety pole piece structure, roll core and cylindrical battery

Abstract

The utility model relates to the technical field of batteries, and discloses a high-safety pole piece structure, a roll core and a cylindrical battery, the high-safety pole piece structure comprises a pole piece, a pole piece head part and a pole piece tail part are respectively formed at the end parts of the two sides of the pole piece, and pole piece coating layer areas are covered on the two surfaces of the pole piece; the periphery of the pole piece head part and the periphery of the empty foil at the pole piece tail part are respectively covered with insulating gummed paper in the circumferential direction; the insulation gummed paper is added to the edges of the end faces of the pole piece head and the pole piece tail, so that the reinforced insulation gummed paper is arranged on the position, corresponding to the cathode, of the end face of the positive pole after the pole piece head and the pole piece tail are wound into a roll core, even if the edges of the end faces of the pole piece head and the pole piece tail pierce a diaphragm layer, the insulation gummed paper can be used for isolation to prevent short circuit caused by contact between the positive pole and the cathode, and the purpose of improving the safety of the battery is achieved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of battery, specifically, relate to a high safety pole piece structure, roll core and cylindrical battery. BACKGROUND

[0002] Lithium ion battery is mainly divided into three kinds of cylindrical, square and soft package battery, wherein the production process of cylindrical lithium ion battery is standardized, the production efficiency is high, the cycle performance is excellent and the consistency is good, and the cylindrical lithium ion battery is widely used in portable electronic equipment, electric vehicle, energy storage system and other fields, cylindrical battery usually includes positive pole piece, negative pole piece and diaphragm arranged between adjacent positive pole piece and negative pole piece for preventing positive pole piece and negative pole piece from directly contacting as insulating component.

[0003] The prior art at least has the following problems: when winding and cutting the pole piece, the prior art pole piece adopts the mode of 'cutting material' or 'cutting foil', when adopting the mode of 'cutting material', the cutting position is in the coating area, the pole piece coating layer is extruded by the cutting knife, and dust is easily formed by falling material into the roll core, causing self-discharge of the battery, and in severe cases, fire and explosion; when adopting the mode of 'cutting foil', the cutting position is in the empty foil area, and the empty foil is usually only 6-16 mu, and when the cutting knife is not tightly engaged during the cutting process, it is relatively difficult to cut the empty foil, and the empty foil is easily deformed or generates metal burrs to pierce the diaphragm, causing the positive pole piece and the negative pole piece to contact in the coating area, resulting in short circuit, and in severe cases, fire and explosion. CONTENT OF THE UTILITY MODEL

[0004] The utility model aims at providing a high safety pole piece structure, which solves the problem of material falling or deformation or metal burr piercing the diaphragm during cutting of the pole piece in the prior art.

[0005] The utility model is realized in this way, a high safety pole piece structure, including pole piece, the both sides of pole piece end part is formed with pole piece head and pole piece tail respectively, both sides of pole piece are covered with pole piece coating layer area, the outer periphery of the circumferential direction of the pole piece head and the outer periphery of the circumferential direction of the pole piece tail empty foil are covered with insulating adhesive tape respectively.

[0006] Further, the pole piece includes a positive pole piece and a negative pole piece, the both sides of the positive pole piece end part are formed with a positive pole head empty foil area and a positive pole tail empty foil area, respectively, a positive pole coating layer area is covered between the positive pole tail empty foil area and the positive pole head empty foil area, the outer periphery of the circumferential direction of the positive pole tail empty foil area and the outer periphery of the circumferential direction of the positive pole head empty foil area are covered with insulating adhesive tape, respectively.

[0007] A middle empty foil area is provided on the middle part of the positive pole piece, the middle empty foil area penetrates the positive pole coating layer area, a positive pole lug is provided in the middle empty foil area, the positive pole lug is connected with the positive pole piece, the middle empty foil area is covered with insulating adhesive tape, and the insulating adhesive tape at least partially covers the positive pole coating layer area on both sides of the middle empty foil area.

[0008] The two side end portions of the negative electrode sheet are respectively formed with a negative electrode head empty foil area and a negative electrode tail empty foil area, a negative electrode coating layer area is covered between the negative electrode head empty foil area and the negative electrode tail empty foil area, the negative electrode coating layer area includes a first coating layer area and a second coating layer area, the first coating layer area and the second coating area are respectively arranged on the front and back surfaces of the negative electrode sheet, the first coating layer area and the second coating layer area are arranged in opposite staggered manner, and the outer circumferences of the negative electrode tail empty foil area and the negative electrode head empty foil area are respectively covered with insulating adhesive tape.

[0009] The negative electrode sheet is connected with a negative electrode tab, the negative electrode tab is located in the negative electrode head empty foil area or the negative electrode tail empty foil area, or the negative electrode head empty foil area and the negative electrode tail empty foil area are respectively provided with a negative electrode tab.

[0010] Further, the insulating adhesive tape is at least partially covered on the edge of the positive electrode coating layer area.

[0011] Further, the insulating adhesive tape in the negative electrode head empty foil area is at least partially covered on the first coating layer area and the second coating layer area.

[0012] The negative electrode tail empty foil area includes a first tail empty foil area and a second tail empty foil area, the first tail empty foil area and the second tail empty foil area are respectively arranged on the front and back surfaces of the negative electrode sheet, the length of the first tail empty foil area is greater than the length of the second tail empty foil area, the two side end portions of the first tail empty foil area are respectively covered with insulating adhesive tape, the two insulating adhesive tapes are arranged in side-by-side spaced manner, the insulating adhesive tape is at least partially covered on the first coating layer area of the first tail empty foil area, and the end portion of the second tail empty foil area away from the second coating layer area is covered with insulating adhesive tape.

[0013] Further, the insulating adhesive tape includes a base material layer with insulating effect and an adhesive layer with adhesive effect.

[0014] Further, the base material layer is a thin film layer of polyethylene terephthalate, polyvinylidene fluoride or polyvinylidene fluoride copolymer, polyurethane or thermoplastic polyurethane, thermoplastic polyester, epoxy polyester, polystyrene, polypropylene, polyimide or a combination thereof.

[0015] The adhesive layer is a thin layer of acrylic acid, rubber or silicone or a combination thereof.

[0016] Compared with the prior art, the high-safety pole piece structure increases insulating adhesive paper at the edge of the end face of the pole piece head and the pole piece tail, so that after being wound into a winding core, the positive electrode end face has enhanced insulating adhesive paper at the corresponding position of the negative electrode, even if the edge of the end face of the pole piece head and the pole piece tail pierces the diaphragm layer, the insulating adhesive paper can be used for isolation, so as to prevent the positive electrode from being in contact with the negative electrode and short-circuiting, and the purpose of improving the safety of the battery is achieved.

[0017] The utility model further provides a winding core, including above-mentioned a kind of high-safety pole piece structure, and the positive pole piece and negative pole piece are isolated by diaphragm layer and are wound to form the winding core.

[0018] Further, the positive electrode head empty foil area and the negative electrode head empty foil area are arranged adjacent, and the positive electrode tail empty foil area and the negative electrode tail empty foil area are arranged adjacent.

[0019] Compared with the prior art, the winding core provided by the utility model saves material cost due to the pole piece structure, and improves production safety, and thus the winding core also reduces cost.

[0020] The utility model further provides a cylindrical battery, including above-mentioned winding core.

[0021] Compared with the prior art, the cylindrical battery provided by the utility model saves material cost due to the winding core, and improves production safety, and thus the cylindrical battery also reduces cost. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is the top view structural schematic diagram of the high-safety pole piece structure provided by the utility model;

[0023] Figure 2 is the front view structural schematic diagram of the positive pole piece provided by the utility model;

[0024] Figure 3 is the front view structural schematic diagram of the negative pole piece provided by the utility model;

[0025] Figure 4 is the top view structural schematic diagram of the negative pole piece provided by the utility model;

[0026] Figure 5 is the bottom view structural schematic diagram of the negative pole piece provided by the utility model.

[0027] In the figure: the polar sheet 10, the insulating adhesive paper 20, the positive polar sheet 30, the negative polar sheet 40, the polar sheet head 11, the polar sheet tail 12, the polar sheet coating layer area 13, the positive polar head empty foil area 31, the positive polar tail empty foil area 32, the positive polar coating layer area 33, the middle empty foil area 34, the positive polar lug 35, the negative polar head empty foil area 41, the negative polar tail empty foil area 42, the negative polar coating layer area 43, the negative polar lug 44, the first tail empty foil area 421, the second tail empty foil area 422, the first coating layer area 431, the second coating layer area 432. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical scheme and advantages of the utility model more clearly, the following will be further described in detail in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the utility model, and are not used to limit the utility model.

[0029] The implementation of the utility model will be described in detail in combination with specific examples.

[0030] The same or similar reference numerals in the drawings of the embodiments correspond to the same or similar components; in the description of the utility model, it should be understood that if the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right" and the like are based on the orientations or positional relationships shown in the drawings, they are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore the terms describing the positional relationships in the drawings are only used for exemplary illustration, and cannot be understood as a limitation on the utility model, for those skilled in the art, the specific meanings of the above terms can be understood according to the specific circumstances.

[0031] Referring to Figures 1-5 The preferred embodiment provided by the utility model is shown in the figure.

[0032] A high-safety polar sheet structure, comprising a polar sheet 10, the two side ends of the polar sheet 10 are respectively formed with a polar sheet head 11 and a polar sheet tail 12, the two surfaces of the polar sheet 10 are covered with a polar sheet coating layer area 13, and the outer circumferential periphery of the polar sheet head 11 and the outer circumferential periphery of the polar sheet tail 12 empty foil are respectively covered with an insulating adhesive paper 20.

[0033] The high-safety pole piece structure provided in the above increases the insulating adhesive paper 20 at the end face edges of the pole piece head 11 and the pole piece tail 12, so that after being wound into a core, the positive electrode end face has the insulating adhesive paper 20 at the corresponding position of the negative electrode, even if the end face edges of the pole piece head 11 and the pole piece tail 12 pierce the diaphragm layer, the insulating adhesive paper 20 can be used for isolation to prevent the positive electrode from contacting the negative electrode and causing short circuit, so as to improve the safety of the battery. The insulating adhesive paper 20 is attached to the two side end portions of the pole piece coating layer area 13, which can prevent the occurrence of material falling during cutting; and the problems of material falling, deformation or metal burr piercing the diaphragm during cutting of the pole piece 10 are solved.

[0034] In the embodiment, the pole piece 10 includes a positive pole piece 30 and a negative pole piece 40. The two side end portions of the positive pole piece 30 are respectively formed with a positive pole head empty foil area 31 and a positive pole tail empty foil area 32. The positive pole tail empty foil area 32 and the positive pole head empty foil area 31 are covered with a positive pole coating layer area 33. The outer circumferences of the positive pole tail empty foil area 32 and the positive pole head empty foil area 31 are respectively covered with insulating adhesive paper 20.

[0035] A middle empty foil area 34 is arranged on the middle portion of the positive pole piece 30. The middle empty foil area 34 penetrates the positive pole coating layer area 33. The middle empty foil area 34 is provided with a positive pole tab 35. The positive pole tab 35 is connected with the positive pole piece 30. The middle empty foil area 34 is covered with insulating adhesive paper 20. The insulating adhesive paper 20 at least partially covers the positive pole coating layer area 33 on the two sides of the middle empty foil area 34.

[0036] The two side end portions of the negative pole piece 40 are respectively formed with a negative pole head empty foil area 41 and a negative pole tail empty foil area 42. The negative pole head empty foil area 41 and the negative pole tail empty foil area 42 are covered with a negative pole coating layer area 43. The negative pole coating layer area 43 includes a first coating layer area 431 and a second coating layer area 432. The first coating layer area 431 and the second coating layer area 432 are respectively arranged on the front and back surfaces of the negative pole piece 40. The first coating layer area 431 and the second coating layer area 432 are relatively staggered. The outer circumferences of the negative pole tail empty foil area 42 and the negative pole head empty foil area 41 are respectively covered with insulating adhesive paper 20.

[0037] The negative pole piece 40 is connected with a negative pole tab 44. The negative pole tab 44 is located at the negative pole head empty foil area 41 or the negative pole tail empty foil area 42. Alternatively, the negative pole head empty foil area 41 and the negative pole tail empty foil area 42 are respectively provided with the negative pole tab 44.

[0038] 1), The first coating layer area 431 and the second coating layer area 432 are staggered and coated. The second coating layer area 432 effectively reduces the waste of active material.

[0039] 2), the positive electrode sheet 30 cutting position avoids the positive electrode coating layer area 33, reduces the generation of dust, is favorable to reduce the battery low voltage bad, improves the battery safety;

[0040] 3), the positive and negative electrode winding takes the "cutting rubber + foil + rubber" mode, which is favorable to keep the cut flat and reduce metal debris;

[0041] 4), the positive electrode head empty foil area 31 is provided with insulating rubber paper 20 at the corresponding position of the negative electrode head empty foil area 41 of the winding core, which strengthens the protection, avoids internal short circuit, and can reduce the flatness requirement of the cutting surface of the positive electrode head 11.

[0042] 5), the positive electrode tail empty foil area 32 is provided with insulating rubber paper 20 at the corresponding position of the negative electrode tail empty foil area 42 of the winding core, which strengthens the protection, avoids internal short circuit, and can reduce the flatness requirement of the cutting surface of the positive electrode tail 12. Even if the positive electrode head and the positive electrode tail edge pierce the diaphragm, the positive electrode and the negative electrode can be prevented from contacting and short circuiting, so as to improve the safety of the battery.

[0043] In the embodiment, the insulating rubber paper 20 at least partially covers the edge of the positive electrode coating layer area 33. In this way, the insulating rubber paper 20 can strengthen the protection of the positive electrode coating layer area 33 and prevent the occurrence of the dropping material during the positive electrode cutting process.

[0044] In the embodiment, the insulating rubber paper 20 in the negative electrode head empty foil area 41 at least partially covers the first coating layer area 431 and the second coating layer area 432;

[0045] The negative electrode tail empty foil area 42 includes a first tail empty foil area 421 and a second tail empty foil area 422, which are respectively arranged on the front and back surfaces of the negative electrode sheet 40. The length of the first tail empty foil area 421 is greater than that of the second tail empty foil area 422. The two side ends of the first tail empty foil area 421 are respectively covered with insulating rubber paper 20, and the two insulating rubber papers 20 are arranged side by side and spaced apart. The insulating rubber paper 20 at least partially covers the first coating layer area 431 of the first tail empty foil area 421, and the end of the second tail empty foil area 422 away from the second coating layer area 432 is covered with insulating rubber paper 20.

[0046] The base material thickness of the insulating rubber paper 20 is 5-200 μm, and the total thickness of the insulating rubber paper 20 is 6-250 μm. The insulating rubber paper 20 can be selected from the same type and thickness, or different types and thicknesses.

[0047] The negative electrode head empty foil area 41 comprises a first head empty foil area and a second head empty foil area, the length of the first head empty foil area is less than the length of the second head empty foil area, the first head empty foil area is on the same plane as the first tail empty foil area 421, and the second head empty foil area is on the same plane as the second tail empty foil area 422.

[0048] The length L1 of the first head empty foil area is set to 5-25mm.

[0049] The length L2 of the second head empty foil area is set to L1+center hole diameter*π-10≤L2≤L1+center hole diameter*π+10.

[0050] The length L3 of the positive electrode head empty foil area 31 is 5-25mm and less than L1.

[0051] The length L2' of the second tail empty foil area 422 is 5-25mm.

[0052] The length L1' of the first tail empty foil area 421 is set to L2'+core diameter*π-10≤L1'≤L2'+core diameter*π+10.

[0053] The length L3' of the positive electrode tail empty foil area 32 is 5-25mm and less than L2'.

[0054] The length l1 of the insulating adhesive tape 20 of the first head empty foil area;

[0055] The length l2 of the insulating adhesive tape 20 of the second head empty foil area;

[0056] The length l3 of the insulating adhesive tape 20 of the positive electrode head empty foil area 31 is set to L3~L3+5, and the edge is flush with the edge of the positive electrode head empty foil area 31.

[0057] The length l1' of the insulating adhesive tape 20 of the first tail empty foil area 421 is 5-25mm

[0058] The length l2' of the insulating adhesive tape 20 of the second tail empty foil area 422 is 5-25mm

[0059] The length l3' of the insulating adhesive tape 20 of the positive electrode tail empty foil area 32 is set to L3'~L3'+5, and the edge is flush with the edge of the positive electrode tail empty foil area 32.

[0060] The insulating adhesive tape 20 comprises a base material layer with insulation and an adhesive layer with adhesion.

[0061] The base material layer is a thin film layer of polyethylene terephthalate, polyvinylidene fluoride or a copolymer of polyvinylidene fluoride, polyurethane or thermoplastic polyurethane, thermoplastic polyester, epoxy polyester, polystyrene, polypropylene, polyimide or a combination thereof.

[0062] The adhesive layer is a thin layer of acrylic, rubber, or silicone, alone or in combination.

[0063] The utility model discloses still provided a roll core, including above-mentioned a high safety pole piece structure, the positive pole piece 30 with negative pole piece 40 are isolated through diaphragm layer and are wound and form roll core.

[0064] In the embodiment, the positive head empty foil area 31 is arranged adjacent to the negative head empty foil area 41, and the positive tail empty foil area 32 is arranged adjacent to the negative tail empty foil area 42.

[0065] The positive head empty foil area 31 is provided with the insulating adhesive paper 20 at the corresponding position of the negative head empty foil area 41 of the roll core, so that the protection is strengthened, internal short circuit is avoided, and the flatness requirement of the cutting surface of the pole piece head 11 is reduced.

[0066] The positive tail empty foil area 32 is provided with the insulating adhesive paper 20 at the corresponding position of the negative tail empty foil area 42 of the roll core, so that the protection is strengthened, internal short circuit is avoided, and the flatness requirement of the cutting surface of the pole piece tail 12 is reduced.

[0067] Compared with the prior art, the roll core provided by the utility model saves material cost of the pole piece structure and improves production safety, and thus the roll core also reduces cost.

[0068] The utility model discloses still provided a cylindrical battery, including above-mentioned roll core.

[0069] Compared with the prior art, the cylindrical battery provided by the utility model saves material cost of the roll core and improves production safety, and thus the cylindrical battery also reduces cost.

[0070] The above only is the preferred embodiment of the utility model, and does not limit the utility model, and any modification, equivalent replacement and improvement etc. in the spirit and principle of the utility model should be included in the protection scope of the utility model.

Claims

1. A high safety pole structure, characterized by, The pole piece includes pole piece head and tail, both sides of the pole piece are covered with pole piece coating layer, the outer periphery of the pole piece head and tail are covered with insulating adhesive tape; The pole piece includes positive pole piece and negative pole piece, both sides of the positive pole piece are formed with positive pole head and tail, the positive pole tail is covered with positive pole coating layer, the outer periphery of the positive pole tail and head are covered with insulating adhesive tape; The middle part of the positive pole piece is provided with middle part foil area, the middle part foil area penetrates the positive pole coating layer, the middle part foil area is provided with positive pole lug, the positive pole lug is connected with the positive pole piece, the middle part foil area is covered with insulating adhesive tape, the insulating adhesive tape at least partially covers the positive pole coating layer on both sides of the middle part foil area; The negative pole piece is provided with negative pole head and tail, the negative pole head and tail are covered with negative pole coating layer, the negative pole coating layer includes first coating layer and second coating layer, the first coating layer and second coating layer are arranged on the front and back of the negative pole piece, the first coating layer and second coating layer are relatively staggered, the outer periphery of the negative pole tail and head are covered with insulating adhesive tape; The negative pole piece is connected with negative pole lug, the negative pole lug is located in the negative pole head or tail, or the negative pole head and tail are provided with negative pole lug.

2. The high safety electrode structure of claim 1, wherein The insulating adhesive tape at least partially covers the edge of the positive pole coating layer.

3. The high safety electrode structure of claim 1, wherein The insulating adhesive tape in the negative pole head at least partially covers the first coating layer and second coating layer; The negative pole tail includes first tail and second tail, the first tail and second tail are arranged on the front and back of the negative pole piece, the length of the first tail is greater than that of the second tail, both sides of the first tail are covered with insulating adhesive tape, the two insulating adhesive tapes are arranged side by side, the insulating adhesive tape at least partially covers the first coating layer of the first tail, the end of the second tail away from the second coating layer is covered with insulating adhesive tape.

4. A high safety electrode structure according to any one of claims 1 to 3, wherein The insulating adhesive tape includes base layer with insulation and adhesive layer with adhesion.

5. A core characterized in that The high safety pole piece structure includes the pole piece structure of any one of claims 1 to 4, the positive pole piece and the negative pole piece are separated by the diaphragm layer and wound to form the core.

6. The core of claim 5 wherein, The positive pole head is adjacent to the negative pole head, and the positive pole tail is adjacent to the negative pole tail.

7. A cylindrical battery characterized by The core includes the core of claim 6.

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