CN217239543U

CN217239543U - Multi-tab winding type lithium ion battery structure

Info

Publication number: CN217239543U
Application number: CN202220633738.1U
Authority: CN
Inventors: 梁永吉; 薛历兴; 张阔
Original assignee: Chuneng New Energy Co Ltd
Current assignee: Chuneng New Energy Co Ltd
Priority date: 2022-03-22
Filing date: 2022-03-22
Publication date: 2022-08-19
Anticipated expiration: 2032-03-22

Abstract

The utility model relates to a lithium ion battery's technical field, concretely relates to multi-tab coiling formula lithium ion battery structure. Roll up the core including a plurality of parallel connection, roll up the core and form by a negative pole piece and a positive plate coiling, the negative pole piece top evenly is provided with a plurality of negative pole mass flow body polar handle, the positive plate top evenly is provided with a plurality of anodal mass flow body polar handle, negative pole mass flow body polar handle and anodal mass flow body polar handle set up in roll core top both sides oppositely, be provided with insulating cover between negative pole mass flow body polar handle and the anodal mass flow body polar handle, it is equipped with the apron to roll up the core top, negative pole mass flow body polar handle and anodal mass flow body polar handle are connected to the apron bottom through a current splitter respectively. The laminated battery has the same current-carrying area as the laminated battery structure, can improve the high-rate charge-discharge performance, and reduces the welding stress of the lugs. Compared with a laminated structure which adopts a plurality of positive and negative pole pieces, the probability of the edge defect of the pole pieces is greatly reduced, and the risk of internal short circuit is reduced.

Description

Multi-tab winding type lithium ion battery structure

Technical Field

The utility model relates to a lithium ion battery's technical field, concretely relates to multi-tab coiling formula lithium ion battery structure.

Background

The lithium ion battery has the advantages of high energy density, high working voltage, safety, environmental protection, no memory effect, long cycle life and the like, and is widely applied to the fields of digital 3C, power, energy storage, new energy automobiles and the like at present.

The high-rate lithium ion battery uses a lamination structure, and the lamination structure has the following defects:

1. the number of pole pieces is large, the lamination efficiency is low, and the production cost is high;

2. the probability of generating burrs and dust of the die-cut pole piece is high, the self-discharge of the battery is large, the consistency is poor, and the hidden danger of internal short circuit and thermal runaway is large;

3. the negative current collector handle and the positive current collector handle of the roll core are arranged in parallel in the width direction of the roll core, and the width of the negative current collector handle or the positive current collector handle usually only accounts for 20% of the width of the roll core. The negative current collector pole shank or the positive current collector pole shank with small width is easy to deform due to welding stress, so that wrinkles appear, and lithium is precipitated due to lithium intercalation abnormality.

SUMMERY OF THE UTILITY MODEL

The utility model aims at the defects of the prior art, and provides a multi-tab winding type lithium ion battery structure which has the same current carrying area as a laminated battery structure, can improve the charge and discharge performance with large multiplying power, reduces the welding stress of tabs, and can greatly improve the production efficiency by adopting the winding structure; meanwhile, as the winding structure adopts one positive and negative pole piece, compared with a lamination structure adopting a plurality of positive and negative pole pieces, the probability of the edge defect of the pole piece is greatly reduced, and the risk of internal short circuit is reduced.

The utility model discloses a many utmost points ear coiling formula lithium ion battery structure, roll up the core including a plurality of parallel connection, it is formed by a negative pole piece and a positive plate coiling to roll up the core, the negative pole piece top is provided with a plurality of negative current collector polar handle monomer, the positive plate top is provided with a plurality of positive current collector polar handle monomer, it sets up negative current collector polar handle and positive current collector polar handle to roll up opposite in core top both sides, negative current collector polar handle comprises a plurality of negative current collector polar handle monomer, positive current collector polar handle comprises a plurality of positive current collector polar handle monomer, be provided with insulating cover between negative current collector polar handle and the positive current collector polar handle, it is equipped with the apron to roll up the core top, negative current collector polar handle and positive current collector polar handle are connected to the apron bottom through a current distribution piece respectively.

It is comparatively preferred, the negative pole mass flow body pole shank monomer of negative pole piece is located the odd number layer of book core, and each layer the negative pole mass flow body pole shank overlaps each other and forms the negative pole mass flow body pole shank, the anodal mass flow body pole shank monomer of positive pole piece is located the even number layer of book core, and each layer the anodal mass flow body pole shank monomer overlaps each other and forms anodal mass flow body pole shank.

Preferably, the negative current collector handle and the positive current collector handle are both triangular structures.

Comparatively preferred, the insulating boot including set up in the negative pole and collect the body of current the division board between the body of current the polar handle and the anodal body of current the polar handle and with division board both ends vertical fixation's backup pad, the backup pad both ends have the restriction portion of turning over to the inboard, form spacing space between the restriction portion of insulating boot both ends backup pad, negative pole and collect the body of current the polar handle and anodal body of current the polar handle are located in the spacing space.

Preferably, the width of the negative electrode current collector handle or the positive electrode current collector handle accounts for 85% -95% of the width of the winding core.

Comparatively preferred, the flow distribution piece is located the backup pad top, flow distribution piece one end and the outside welded fastening of negative pole mass flow body polar handle or positive pole mass flow body polar handle, the other end and apron bottom welded fastening.

Preferably, the winding cores are connected in parallel through conducting strips.

The utility model has the advantages that: adopt the book core of coiling formula, the thickness direction both sides of this book core are negative pole mass flow body polar handle and anodal mass flow body polar handle respectively, adopt this kind of mode, compare in the width account for than the low traditional parallel design scheme of ratio, and it has the same current-carrying area with lamination battery structure, has improved big multiplying power charge-discharge performance. And only one nearby sheet and one positive plate are needed by adopting a winding structure, so that the production efficiency can be greatly improved. Meanwhile, the winding structure adopts a positive pole piece and a negative pole piece, so that the probability of edge defects of the pole pieces is greatly reduced and the risk of internal short circuit is reduced compared with a plurality of positive pole pieces and negative pole pieces adopted by a lamination structure. And the wider tab can avoid the tab position from being deformed due to the influence of welding stress during welding, thereby avoiding the occurrence of wrinkles and lithium precipitation caused by abnormal lithium embedding. The negative current collector pole handle and the positive current collector pole handle are designed to be triangular structures, so that the weight can be reduced, the energy density can be increased, the space can be saved, and the efficiency can be improved during liquid injection.

Drawings

FIG. 1 is a schematic diagram of the pole piece structure of the present invention;

fig. 2 is a schematic view of the distribution of the negative current collector electrode handle and the positive current collector electrode handle on the roll core;

fig. 3 is the utility model discloses a splitter plate and negative pole mass flow body polar stalk, anodal mass flow body polar stalk and the connection schematic diagram of apron.

Detailed Description

In order to make the technical problems, technical solutions and advantageous effects to be solved by the present application clearer, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

It will be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like, refer to an orientation or positional relationship illustrated in the drawings for convenience in describing the present application and to simplify description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

Example one

Fig. 1 to 3 are schematic structural diagrams of preferred embodiments of the present application, and for convenience of description, only the portions related to the present embodiments are shown, which are detailed as follows:

the utility model provides a many utmost points ear coiling formula lithium ion battery structure, includes a plurality of parallel connection's book core 2, it is formed by coiling under the effect of tension to roll up core 2 by a negative pole piece 11 and a positive plate 13, negative pole piece 11 top evenly is provided with a plurality of negative current collector polar handle monomer 12, positive plate 13 top evenly is provided with a plurality of positive current collector polar handle monomer 14, it sets up negative current collector polar handle 21 and positive current collector polar handle 22 to roll up core 2 top both sides opposition, negative current collector polar handle 21 comprises a plurality of negative current collector polar handle monomer 12, current collector polar handle 22 comprises a plurality of positive current collector polar handle monomer 14, be provided with insulating cover 23 between negative current collector polar handle 21 and the positive current collector polar handle 22, it is equipped with apron 33 to roll up core 2 top, negative current collector polar handle 21 and positive current collector polar handle 22 are respectively through a

current splitter

31, 32 are attached to the bottom of the cover plate 33.

The negative electrode current collector handle single bodies 12 of the negative electrode plate 11 are positioned on odd layers (such as 1, 3, 5, 7 and 9 … …) of the winding core 2, the negative electrode current collector handle 21 of each layer is mutually overlapped to form a negative electrode current collector handle 21, the positive electrode current collector handle single bodies 14 of the positive electrode plate 13 are positioned on even layers (such as 2, 4, 6, 8 and 10 … …) of the winding core 2, and the positive electrode current collector handle single bodies 14 of each layer are mutually overlapped to form a positive electrode current collector handle 22. The interval between the negative current collector handle single bodies 12 of the negative plate 11 is set according to the width of the winding core, and specifically, when the negative plate 11 needs to be wound, each odd layer can just have one negative current collector handle single body 12, and the negative current collector handle single bodies 12 on each layer just coincide. The interval between the positive current collector handle monomers 14 of the positive plate 13 is also set according to the width of the winding core, and particularly, when the positive plate 13 is wound, each even layer can be just provided with one positive current collector handle monomer 14, and the positive current collector handle monomers 14 on each layer are just overlapped.

Negative pole mass flow body utmost point handle 21 and positive pole mass flow body utmost point handle 22 are the triangle-shaped structure, and this triangle-shaped structure is isosceles triangle, and the both sides that these isosceles triangle equals are hypotenuse about the triangle-shaped structure, and the preferred obtuse angle of apex angle of this triangle-shaped structure, this embodiment is 120.

The insulating sleeve 23 comprises a separation plate 231 arranged between the negative current collector pole handle 21 and the positive current collector pole handle 22 and support plates 232 vertically fixed with two ends of the separation plate 231, two ends of the support plates 232 are provided with limiting parts 233 turned inwards, a limiting space is formed between the limiting parts 233 of the support plates 232 at two ends of the insulating sleeve 23, and the negative current collector pole handle 21 and the positive current collector pole handle 22 are positioned in the limiting space.

The width of the negative current collector electrode handle 21 or the positive current collector electrode handle 22 accounts for 85% -95% of the width of the winding core 2, and 90% is adopted in the embodiment.

The

diverter blades

31, 32 are positioned above the support plate 232, and may have gaps or contact with each other. One end of each of the

splitter plates

31 and 32 is welded and fixed with the outer side of the negative current collector pole handle 21 or the positive current collector pole handle 22, and the other end is welded and fixed with the bottom of the cover plate 33.

The winding cores 2 are connected in parallel through conducting strips, and the conducting strips can be made of rigid materials or flexible materials. The winding cores are arranged along the thickness direction of the winding cores, and the connection of the anode and the cathode of the adjacent winding cores and the connection of the cathode and the anode of the adjacent winding cores are realized through the conducting strips.

The shape of book core 2 is square or cuboid, anodal mass flow body utmost point handle 22 is the aluminium foil, negative pole mass flow body utmost point handle 21 is aluminium foil or copper foil.

The winding core of the scheme is sequentially subjected to packaging, baking, liquid injection, standing, formation, aging and capacity grading to prepare the multi-tab winding type lithium ion battery. Because of adopting the multi-tab structure, the capacity of the battery for resisting super-large current is fully ensured, and meanwhile, the production efficiency is greatly improved because only one negative plate 11 and one positive plate 13 are provided; because the number of the pole pieces is reduced, the edge defects of the pole pieces are reduced, the safety performance is improved, and the potential safety hazards of the battery cell are greatly reduced.

The above-mentioned embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.

Claims

1. The utility model provides a multi-tab coiling formula lithium ion battery structure which characterized in that: roll up core (2) including a plurality of parallel connection, roll up core (2) and form by convoluteing a negative plate (11) and a positive plate (13), negative plate (11) top is provided with a plurality of negative current collector polar handle monomer (12), positive plate (13) top is provided with a plurality of anodal current collector polar handle monomer (14), roll up core (2) top both sides are opposite to be provided with negative current collector polar handle (21) and anodal current collector polar handle (22), negative current collector polar handle (21) comprises a plurality of negative current collector polar handle monomer (12), anodal current collector polar handle (22) comprises a plurality of anodal current collector polar handle monomer (14), be provided with insulating cover (23) between negative current collector polar handle (21) and the anodal current collector polar handle (22), it is equipped with apron (33) to roll up core (2) top, negative current collector polar handle (21) and anodal current collector polar handle (22) are respectively through a branch flow piece (31), 32) is connected to the bottom of the cover plate (33).

2. The multi-tab wound lithium ion battery structure of claim 1, wherein: the single negative current collector handle (12) of negative pole piece (11) is located the odd number layer of core (2), and each layer negative current collector handle (21) overlap each other and form negative current collector handle (21), the single positive current collector handle (14) of positive pole piece (13) is located the even number layer of core (2), and each layer single positive current collector handle (14) overlap each other and form positive current collector handle (22).

3. The multi-tab wound lithium ion battery structure of claim 1, wherein: the negative current collector pole handle (21) and the positive current collector pole handle (22) are both triangular structures.

4. The multi-tab wound lithium ion battery structure of claim 1, wherein: insulating boot (23) including set up division board (231) between negative pole current collector polar handle (21) and anodal current collector polar handle (22) and with division board (231) both ends vertical fixation's backup pad (232), backup pad (232) both ends have to the inboard limited part (233) of turning over and rolling over, form spacing space between limited part (233) of insulating boot (23) both ends backup pad (232), negative pole current collector polar handle (21) and anodal current collector polar handle (22) are located in the spacing space.

5. The multi-tab wound lithium ion battery structure of claim 1, wherein: the width of the negative current collector electrode handle (21) or the positive current collector electrode handle (22) accounts for 85-95% of the width of the winding core (2).

6. The multi-tab wound lithium ion battery structure of claim 4, wherein: the flow distribution piece (31, 32) is located backup pad (232) top, flow distribution piece (31, 32) one end and the outside welded fastening of negative pole mass collector polar handle (21) or positive pole mass collector polar handle (22), the other end and apron (33) bottom welded fastening.

7. The multi-tab wound lithium ion battery structure of claim 1, wherein: the winding cores (2) are connected in parallel through conducting strips.