CN213878232U

CN213878232U - Large-column lithium ion battery structure

Info

Publication number: CN213878232U
Application number: CN202022869818.0U
Authority: CN
Inventors: 郭春泰; 从长杰; 陈保国; 李文文; 马华
Original assignee: Tianjin EV Energies Co Ltd
Current assignee: Tianjin EV Energies Co Ltd
Priority date: 2020-12-03
Filing date: 2020-12-03
Publication date: 2021-08-03
Anticipated expiration: 2030-12-03

Abstract

The utility model provides a big cylinder lithium ion battery structure belongs to power battery technical field, including the apron, the apron includes outer utmost point post, first seal gasket, battery cover, interior utmost point post, second seal gasket and connecting piece, the battery covers there is the hole, there is the arch on the interior utmost point post, and the hole is passed to the arch, first seal gasket is installed at bellied upper surface, outer utmost point post is installed and is kept away from bellied one end at first seal gasket, the one end that first seal gasket was kept away from at interior utmost point post is installed to second seal gasket, interior utmost point post, first seal gasket and outer utmost point post are passed in proper order to the connecting piece. The utility model discloses simple structure has reduced part kind and quantity, has reduced the assembly difficulty, light in weight, and is with low costs, has promoted the energy density of battery.

Description

Large-column lithium ion battery structure

Technical Field

The utility model belongs to the technical field of power battery, a big cylinder lithium ion battery structure is related to.

Background

Along with the development and progress of new energy automobile technology, higher requirements are provided for the energy density, the cycle life, the safety and the reliability of the lithium ion battery, and the advantages of the cylindrical battery in the aspects of process maturity, negative electrode expansion inhibition, thermal runaway propagation inhibition and the like are more and more obvious, so that the requirements of the structure and the assembly method of the cylindrical battery are more diversified and greatly increased.

The cylindrical lithium ion battery structure commonly used at present comprises parts such as book core, the apron, cylinder shell, and the pole piece coating back has been accomplished, and utmost point ear is welded according to the position definition, and the cylindrical book core of taking utmost point ear is rolled up to the pole piece through the coiling mode, and it is good to roll up the mass flow body welding on core and the upper and lower apron, wholly pushes the cylinder shell after, apron and shell are welded together through laser welding, and this kind of battery structure is complicated, the part kind is various, assembly process is many, the uniformity control degree of difficulty is big.

When a winding core is connected with an upper cover through a pole lug to output current, the size of the pole lug is smaller due to space limitation, the overcurrent capacity of a cylindrical battery is limited, the connection impedance of the battery is also increased, the battery generates heat seriously, the cylindrical battery is influenced by the structure, the radial heat transfer rate of the cylinder is slower than the axial heat transfer rate, the heat is accumulated in the winding core and can not be transferred, and thus a heating safety accident is caused, in addition, in the manufacturing process of the winding core, a pole lug welding procedure is required to be added, the risk of poor welding is caused, in addition, a pole lug rubbing and flattening process is adopted, the top of a full pole lug winding core is rubbed and ground through the mechanical outside, a cover plate is provided with a foldable connecting sheet and is welded to the pole lug part of the winding core in a laser welding way, and the process defect is that the rubbed and flattened winding core is difficult to infiltrate electrolyte into each layer of pole piece of the winding core in the subsequent liquid injection procedure, the infiltration is poor, the connecting sheet needs to be folded, a flexible bendable structure is needed, the overcurrent capacity is also affected, and heat cannot be transferred out through the connecting sheet.

SUMMERY OF THE UTILITY MODEL

The to-be-solved problem of the utility model is a big cylinder lithium ion battery structure belongs to power battery technical field, and simple structure has reduced part kind and quantity, has reduced the assembly difficulty, light in weight, and is with low costs, has promoted the energy density of battery.

In order to solve the technical problem, the utility model discloses a technical scheme is: big post lithium ion battery structure belongs to power battery technical field, including the apron, and the apron includes outer utmost point post, first seal gasket, battery cover, interior utmost point post, second seal gasket and connecting piece, there is the hole on the battery cover, there is the arch on the interior utmost point post, and the hole is passed in the arch, first seal gasket is installed at bellied upper surface, outer utmost point post is installed and is kept away from bellied one end at first seal gasket, the one end that first seal gasket was kept away from at interior utmost point post is installed to second seal gasket, interior utmost point post, first seal gasket, outer utmost point post and outer utmost point post connection are passed in proper order to the connecting piece.

Furthermore, an explosion-proof valve is arranged on the battery cover.

Furthermore, the material of outer utmost point post and interior utmost point post is the aluminum alloy, and the material of connecting piece is copper.

Furthermore, the battery cover is made of modified plastics.

Further, still include the conductive adhesive bonding sheet, first insulation piece, roll up the core, second insulating piece and shell, the apron, the conductive adhesive bonding sheet, first insulation piece, roll up the core and the second insulating piece is coaxial to be set gradually from left to right, the one end and the connecting piece that first insulation piece was kept away from to the conductive adhesive bonding sheet are connected, the shell is installed in the outside of rolling up the core, the one end at the shell is installed to the apron, there is utmost point ear in the one end that the core is close to first insulation piece, utmost point ear passes first insulating piece and the conductive adhesive bonding sheet is connected.

Furthermore, a plurality of tabs are arranged, and the bending angle of the tabs is 60-80 degrees or 180 degrees.

Compared with the prior art, the utility model has the advantages and positive effect as follows:

1. the utility model discloses simple structure has reduced part kind and quantity, has reduced the assembly difficulty, light in weight, and is with low costs, has promoted the energy density of battery.

2. The utility model discloses a battery is covered and is had explosion-proof valve, and explosion-proof valve is annular evenly distributed on the apron, and exhaust route and gas vent area are bigger, and the gas pressure who erupts is lower, has reduced high fever, high-pressure gas to the influence of adjacent battery, and the suppression prevents the heat diffusion even to take place.

3. The utility model discloses a material of battery cover is modified plastic, can play fine electric insulating property, and when the thermal runaway aggravation, whole battery cover can melt, increases exhaust passage.

4. The utility model discloses a utmost point ear passes first insulating piece and electrically conducts the sticky piece and connects, and the effective area of overflowing of electricity core can reach 90% of rolling up the core sectional area, and is electrically conductive effectual.

5. The utility model discloses a bending angle of utmost point ear is 60 ~ 80 or 180, and utmost point ear department after the coiling has the design auxiliary wheel to tighten up, and every layer utmost point ear all superposes together again, forms the stable structure of fine and close relatively, the electrolyte infiltration of being convenient for.

Drawings

The accompanying drawings, which form a part hereof, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention without undue limitation. In the drawings:

fig. 1 is a schematic diagram of the structure of a large cylindrical lithium ion battery of the present invention;

fig. 2 is an exploded view of the structure of the large cylindrical lithium ion battery of the present invention;

fig. 3 is an exploded view of the cover plate of the large cylindrical lithium ion battery structure of the present invention;

fig. 4 is a schematic diagram of the rolled core of the large cylindrical lithium ion battery structure according to the present invention after being unfolded;

fig. 5 is a schematic diagram of fig. 4 showing a large cylindrical lithium ion battery according to the present invention;

fig. 6 is a schematic diagram 1 of a tab of a large cylindrical lithium ion battery structure according to the present invention;

fig. 7 is a schematic diagram 2 of a tab of the large cylindrical lithium ion battery structure of the present invention.

Reference numerals:

1. a cover plate; 2. a conductive adhesive sheet; 3. a first insulating sheet; 4. a winding core; 5. a second insulating sheet; 6. a housing; 11. an outer pole; 12. a first sealing gasket; 13. a battery cover; 14. an inner pole; 15. a second sealing gasket; 16. a connecting member; 17. an explosion-proof valve; 41. a tab; 131. a hole; 141. and (4) protruding.

Detailed Description

It should be noted that, in the present invention, the embodiments and features of the embodiments may be combined with each other without conflict.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention. Furthermore, the terms "first", "second", etc. 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," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art through specific situations.

The following detailed description of the embodiments of the present invention will be made with reference to the accompanying drawings.

As shown in fig. 1-7, the utility model discloses a big cylinder lithium ion battery structure belongs to power battery technical field, including apron 1, apron 1 includes outer utmost point post 11, first seal gasket 12, a battery cover 13, interior utmost point post 14, second seal gasket 15 and connecting piece 16, porose hole 131 on the battery cover 13, there is protruding 141 on the interior utmost point post 14, protruding 141 passes hole 131, first seal gasket 12 is installed at protruding 141's upper surface, the one end that protruding 141 was kept away from at first seal gasket 12 is installed to outer utmost point post 11, second seal gasket 15 is installed at the one end that first seal gasket 12 was kept away from in interior utmost point post 14, connecting piece 16 passes second seal gasket 15 in proper order, interior utmost point post 14, first seal gasket 12, outer utmost point post 11 and outer utmost point post 11 are connected, connecting piece 16 can be the rivet.

Preferably, there is explosion-proof valve 17 on battery cover 13, explosion-proof valve 17 is annular evenly distributed on apron 1, explosion-proof valve 17's exhaust route and gas vent area are big, the gas pressure who erupts is lower, the influence of high fever, high-pressure gas to adjacent battery has been reduced, restrain or even prevent the thermal diffusion to take place, the annular groove in explosion-proof valve 17 region has increased creepage distance, the whole insulating withstand voltage grade of battery obtains promoting, battery thermal runaway back, explosion-proof valve 17 can open earlier, the whole security of battery system obtains promoting.

Preferably, the material of the outer pole 11 and the inner pole 14 is aluminum alloy, the material of the connecting piece 16 is copper, preferably T2 red copper, and the outer pole 11, the inner pole 14 and the connecting piece 16 have good conductivity and low internal resistance, so that the battery has good electrical property.

Preferably, the material of the battery cover 13 is modified plastic, the material is modified by blending polyphenylene oxide, polypropylene and glass fiber, the modified plastic has low shrinkage rate, the structural shape of the part can be ensured, and good sealing performance with the shell 6 is ensured, the modified material is resistant to electrolyte corrosion, the performance of the material soaked with the electrolyte for a long time is not attenuated, the service life cycle of the battery is ensured, meanwhile, the modified plastic can play a good role in electrical insulation, the thermal deformation temperature of the modified material is 120-140 ℃, the service temperature requirement of the service life cycle of the battery is met, the flame retardant grade of UL90-V0 is met, the explosion-proof valve 17 can be opened in the early stage of thermal runaway, when the thermal runaway is aggravated, the gas production is increased, the whole battery cover 13 can be melted, and the exhaust passage is increased.

Preferably, the cover plate 1, the conductive adhesive sheet 2, the first insulating sheet 3, the winding core 4 and the second insulating sheet 5 are coaxially and sequentially arranged from left to right, one end of the conductive adhesive sheet 2, which is far away from the first insulating sheet 3, is connected with the connecting piece 16, the shell 6 is installed on the outer side of the winding core 4, the cover plate 1 is installed at one end of the shell 6, one end of the winding core 4, which is close to the first insulating sheet 3, is provided with a tab 41, the tab 41 penetrates through the first insulating sheet 3 to be connected with the conductive adhesive sheet 2, the conductive adhesive sheet 2 is an electrolyte-resistant base material and consists of a base body, a conductive polymer and an inorganic conductive agent, the base body is made of any one or a combination of more than two of silicon rubber, polyurethane rubber, chloroprene rubber, modified acrylic resin, phenolic resin and terpene resin, the conductive polymer is made of any one or a combination of more than two of polypyrrole, polyaniline, polythiophene, polyparaphenylene and polydopamine, the conductive polymer preferably has a doped high-conductivity polymer, the inorganic conductive agent is made of any one or a combination of more than two of silver, copper, gold, aluminum, nickel, iron, tin, zinc, graphite, carbon black, carbon nanotubes, carbon fibers, graphene or VGCF, the conductive adhesive sheet 2 has high conductivity and certain elasticity, the effective flow area of the battery core can reach 90% of the sectional area of the winding core 4, the conductive effect is good, and the heat of the battery can be transmitted to the shell 6 and the cover plate 1 in the axial direction of the battery through the tab 41, so that the heat dissipation effect is achieved.

Preferably, there are a plurality of tabs 41, the bending angle of the tabs 41 is 60 ° to 80 ° as shown in fig. 6 or 180 ° as shown in fig. 7, the wound tabs 41 are tightened by a shaping auxiliary wheel, and each layer of tabs 41 are stacked together to form a relatively compact and stable structure for facilitating the penetration of electrolyte.

In the actual working process, before rolling up core 4 and coiling, need cut whole piece utmost point ear 41, as shown in fig. 5, width m and height n of single utmost point ear 41 after cutting can be adjusted according to the design, the shape also can change according to the technological requirement, the utmost point ear 41 can be got rid of in the first 2 ~ 3 weeks of coiling, it is 1 circle every to coil, can get rid of utmost point ear 41 of certain size, can form utmost point ear 41 at specific size interval according to the pole piece area, guarantee the overcurrent demand of pole piece, it installs in the sealed area that apron 1 and shell 6 constitute to roll up core 4.

While one embodiment of the present invention has been described in detail, the description is only a preferred embodiment of the present invention, and should not be considered as limiting the scope of the present invention. All the equivalent changes and improvements made according to the application scope of the present invention should still fall within the patent coverage of the present invention.

Claims

1. Big cylinder lithium ion battery structure, its characterized in that: including the apron, the apron includes outer utmost point post, first seal gasket, battery cover, interior utmost point post, second seal gasket and connecting piece, there is the hole on the battery cover, there is the arch on the interior utmost point post, and the arch passes the hole, first seal gasket is installed at bellied upper surface, outer utmost point post is installed and is kept away from bellied one end at first seal gasket, the one end that first seal gasket was kept away from at interior utmost point post is installed to second seal gasket, interior utmost point post, first seal gasket, outer utmost point post and outer utmost point post connection are passed in proper order to the connecting piece.

2. The large cylindrical lithium ion battery structure of claim 1, wherein: the battery cover is provided with an explosion-proof valve.

3. The large cylindrical lithium ion battery structure of claim 1, wherein: the material of outer utmost point post and interior utmost point post is the aluminum alloy, and the material of connecting piece is copper.

4. The large cylindrical lithium ion battery structure of claim 1, wherein: the battery cover is made of modified plastics.

5. The large cylindrical lithium ion battery structure according to any one of claims 1 to 4, characterized in that: still include conductive adhesive bonding sheet, first insulation piece, roll up the core, second insulating piece and shell, the apron, conductive adhesive bonding sheet, first insulation piece, roll up the core and the second insulating piece is coaxial to be set gradually from left to right, the one end and the connecting piece that first insulation piece was kept away from to conductive adhesive bonding sheet are connected, the shell is installed in the outside of rolling up the core, the one end at the shell is installed to the apron, the one end that the core is close to first insulation piece has utmost point ear, utmost point ear passes first insulating piece and conductive adhesive bonding sheet and connects.

6. The large cylindrical lithium ion battery structure of claim 5, wherein: the number of the pole lugs is multiple, and the bending angle of the pole lugs is 60-80 degrees or 180 degrees.