CN210692651U

CN210692651U - Environment-friendly lithium battery diaphragm with high strength

Info

Publication number: CN210692651U
Application number: CN201921863472.4U
Authority: CN
Inventors: 李军
Original assignee: Shishi Shentai New Material Technology Co Ltd
Current assignee: Shishi Shentai New Material Technology Co Ltd
Priority date: 2019-10-31
Filing date: 2019-10-31
Publication date: 2020-06-05
Anticipated expiration: 2029-10-31

Abstract

The utility model relates to the technical field of lithium batteries, in particular to an environment-friendly lithium battery diaphragm with high strength, which mainly solves the problem of low strength of the lithium battery diaphragm in the prior art and comprises a frame body, the diaphragm comprises a frame body and a substrate made of epoxy resin material and arranged in the frame body, wherein the substrate and the frame body are fixedly connected to form a diaphragm substrate with a plate-shaped structure, the front and back surfaces of the diaphragm substrate are respectively provided with diaphragm membrane bodies, the opposite surfaces of the two diaphragm membrane bodies are uniformly sprayed with a plurality of ceramic layer sheets, the ceramic layer sheets are in a circular sheet structure, are distributed in an array form, are sprayed with a protective layer made of partial methyl methacrylate, through holes are formed in the positions, corresponding to the ceramic layer pieces, of the protective layer, the ceramic layer pieces are exposed to the outside, and the peripheries of the through holes on the protective layer cover the peripheries of the ceramic layer pieces.

Description

Environment-friendly lithium battery diaphragm with high strength

Technical Field

The utility model relates to a lithium cell technical field especially relates to an environmental protection lithium cell diaphragm with high strength.

Background

With the upgrading of consumer electronics and the rapid development of power vehicles, energy storage devices are being developed toward higher energy density, longer service life and higher safety. Among all secondary batteries, lithium ion batteries have characteristics of high specific energy, high specific power, long cycle life, excellent high and low temperature performance, and the like, and have been widely used in various fields. But is limited by the nature of the material itself and the process. When the energy density of the lithium ion battery is improved, the power performance, the cycle life, the high-temperature performance, the safety and other performances of the lithium ion battery are limited in different degrees, and the diaphragm is deformed in the use process due to low strength, namely, the diaphragm expands in the thickness direction in the charge-discharge use process of the lithium ion battery, and then certain internal stress exists in the diaphragm, if the surface of the diaphragm is not bound by the diaphragm and a pole piece by adhesive glue, the battery deforms, and finally the performance of the battery deteriorates; the influence on the safety performance related to the diaphragm is that when the lithium ion battery is heated or internal short circuit occurs, the diaphragm can be heated and contracted, so that large-area internal short circuit in the battery is caused, thermal runaway is caused, and the phenomena of smoking, firing and explosion of the battery are caused.

Chinese patent application No.: 201821333124.1 discloses a multilayer lithium battery diaphragm, including the lithium battery diaphragm membrane body, the intermediate position department of lithium battery diaphragm membrane body is provided with the polyurethane substrate layer, and the both sides of polyurethane substrate layer all are provided with the back up coat, and the both sides of back up coat all are provided with the porous fiber layer, the outside of polyurethane substrate layer is provided with the stability structural layer, and the non-woven fabrics basic unit has been laid to the inboard of stability structural layer, the ultra high molecular polyvinyl chloride layer has been laid to the outside of non-woven fabrics basic unit, and the polyvinyl alcohol material layer has been laid to the outside on ultra high molecular polyvinyl chloride layer, the outside on stability structural layer evenly is provided with the ion hole, and the ion hole runs through polyvinyl alcohol material layer and ultra high molecular polyvinyl chloride layer, the outside on stability structural layer is provided with the SiO. This battery diaphragm is provided with the SiO material coating through setting up stability structural layer and outside for the intensity of battery diaphragm membrane body is strengthened, but, the bonding interface intensity of SiO material coating and diaphragm is very weak in the use, has caused whole SiO material coating to drop easily in the inflation of diaphragm membrane body, and the ceramic powder piece that not only does not improve lithium ion battery diaphragm's intensity on the contrary has influenced lithium ion battery's electrical property because of droing.

SUMMERY OF THE UTILITY MODEL

Therefore, to foretell problem, the utility model provides an environmental protection lithium cell diaphragm with high strength, it has mainly solved the problem that lithium cell diaphragm's intensity is low among the prior art.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

the utility model provides an environmental protection lithium cell diaphragm with high strength, includes the framework, the framework and locate the base plate of being made by the epoxy material in the framework, base plate and framework fixed connection form platelike structure's diaphragm base plate, the two sides are provided with the diaphragm membrane body respectively around the diaphragm base plate, two equal even spraying has a plurality of ceramic lamina on the diaphragm membrane body opposite face, the ceramic lamina is circular sheet structure, each the ceramic lamina is array distribution, the spraying has the protective layer of being made by local methyl methacrylate on the ceramic lamina, there is the through-hole with each ceramic lamina corresponding position on the protective layer for the ceramic lamina exposes in the outside, the week that lies in the through-hole on the protective layer is covered on the week edge of ceramic lamina.

Furthermore, the ratio of the area of each through hole to the area of the corresponding ceramic layer sheet is 0.3-0.7.

Furthermore, the framework includes upper frame strip, lower framework, left frame strip and the right framework that connects through bolt lock, the interior frame face of upper frame strip, lower framework, left frame strip and right framework all is provided with the bar groove for the end edge embedding of base plate is connected.

Further, the distance between the middle points of two adjacent ceramic layer sheets is 50-80 μm.

By adopting the technical scheme, the beneficial effects of the utility model are that: the environment-friendly lithium battery diaphragm with high strength is characterized in that a diaphragm substrate is formed by arranging a frame body and a substrate made of epoxy resin materials, and a diaphragm membrane body is arranged on the diaphragm substrate, so that the physical stability of the diaphragm membrane body is good, ceramic lamina is uniformly sprayed on the diaphragm membrane body, the strength of the diaphragm membrane body is increased, the thermal stability of the diaphragm membrane body is improved, meanwhile, the ceramic lamina is prevented from falling off through a protective layer, through holes in the protective layer ensure the permeability of lithium ions, the electrical property of a lithium ion battery is prevented from being influenced, further, the ceramic lamina is arranged on the opposite surfaces of the two diaphragm membrane bodies, a protective effect is achieved, the strength of the diaphragm membrane body is ensured, and meanwhile, the durability of the diaphragm membrane body is better; furthermore, the ratio of the area of each through hole to the area of the corresponding ceramic layer sheet is 0.3-0.7, so that the protective layer can well cover the ceramic layer sheet and prevent the ceramic layer sheet from being separated, and meanwhile, the passing performance of lithium ions is guaranteed to be maximum; furthermore, the substrate is embedded into the frame body formed by the upper frame strip, the lower frame body, the left frame strip and the right frame body, so that the connection is firm, and the physical strength of the diaphragm substrate is ensured.

Drawings

FIG. 1 is a schematic cross-sectional structural view of an embodiment of the present invention;

FIG. 2 is a schematic diagram of the distribution structure of the diaphragm membrane, the ceramic layer sheet and the connection layer in the embodiment of the present invention;

fig. 3 is a schematic structural diagram of the frame and the substrate in the embodiment of the present invention.

Detailed Description

The present invention will now be further described with reference to the accompanying drawings and detailed description.

The embodiment of the utility model provides a do:

referring to fig. 1, 2 and 3, an environment-friendly lithium battery separator with high strength includes a frame 1, the frame 1 and a substrate 2 made of an epoxy resin material and disposed in the frame 1, the substrate 2 and the frame 1 are fixedly connected to form a separator substrate 3 with a plate-shaped structure, two front and back surfaces of the separator substrate 3 are respectively provided with a separator film body 4, twenty-three ceramic sheets 5 are uniformly sprayed on opposite surfaces of the two separator film bodies 4, the ceramic sheets 5 are in a circular sheet structure, each ceramic sheet 5 is distributed in an array form, a distance between midpoints of two adjacent ceramic sheets 5 is 60 μm, a protective layer 6 made of localized methyl methacrylate is sprayed on the ceramic sheets 5, through holes 7 are disposed on the protective layer 6 corresponding to the ceramic sheets 5, so that the ceramic sheets 5 are exposed to the outside, a circumferential edge of the protective layer 6 located at the through hole 7 covers a circumferential edge of the ceramic sheet 5, the ratio of the area of each through-hole 7 to the area of the corresponding ceramic layer sheet 5 was 0.4.

In this embodiment, the frame body 1 includes an upper frame strip 11, a lower frame body 12, a left frame strip 13, and a right frame body 14 that are connected by bolt locking, and the inner frame surfaces of the upper frame strip 11, the lower frame body 12, the left frame strip 13, and the right frame body 14 are all provided with a strip-shaped groove 8, so that the end edges of the substrate 2 are connected in an embedded manner.

The utility model discloses a working method is: the environment-friendly lithium battery diaphragm with high strength is characterized in that a diaphragm substrate 3 is formed by arranging a frame body 1 and a substrate 2 made of epoxy resin materials, and a diaphragm membrane body 4 is arranged on the diaphragm substrate 3, so that the physical stability of the diaphragm membrane body 4 is good, the strength of the diaphragm membrane body 4 is increased by uniformly spraying a ceramic layer sheet 5 on the diaphragm membrane body 4, the thermal stability of the diaphragm membrane body 4 is improved, meanwhile, the ceramic layer sheet 5 is prevented from falling off by an arranged protective layer 6, through holes 7 on the protective layer 6 ensure the permeability of lithium ions, the electrical property of a lithium ion battery is prevented from being influenced, further, the ceramic layer sheets 5 are arranged on the opposite surfaces of the two diaphragm membrane bodies 4, the protective effect is achieved, and the durability of the diaphragm membrane body 4 is better while the strength of the diaphragm membrane body 4 is ensured; the ratio of the area of each through hole 7 to the area of the corresponding ceramic layer sheet 5 is 0.4, so that the protective layer 6 can well cover the ceramic layer sheet 5 and prevent the ceramic layer sheet 5 from being separated, and meanwhile, the passing performance of lithium ions is ensured to be maximum; the substrate 2 is embedded into the frame body 1 formed by the upper frame strip 11, the lower frame strip 12, the left frame strip 13 and the right frame strip 14, so that the connection is firm, and the physical strength of the diaphragm substrate 3 is ensured.

While the invention has been particularly shown and described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. The utility model provides an environmental protection lithium cell diaphragm with high strength which characterized in that: the improved diaphragm plate comprises a frame body, the framework and locate the base plate of being made by the epoxy material in the framework, base plate and framework fixed connection form platelike structure's diaphragm base plate, the two sides are provided with the diaphragm membrane body respectively around the diaphragm base plate, two equal even spraying has a plurality of ceramic lamella on the diaphragm membrane body opposite face, the ceramic lamella is circular sheet structure, each ceramic lamella is array distribution, the spraying has the protective layer of being made by local methyl methacrylate on the ceramic lamella, there is the through-hole with each ceramic lamella relevant position on the protective layer for the ceramic lamella exposes in the outside, the week that lies in the through-hole on the protective layer is along covering on the week of ceramic lamella.

2. The separator for a lithium battery having high strength according to claim 1, wherein: the ratio of the area of each through hole to the area of the corresponding ceramic layer sheet is 0.3-0.7.

3. The separator for a lithium battery having high strength according to claim 2, wherein: the framework includes upper frame strip, lower framework, left frame strip and the right framework that connects through bolt lock, the interior frame face of upper frame strip, lower framework, left frame strip and right framework all is provided with the bar groove for the end edge embedding of base plate is connected.

4. The separator for a lithium battery having high strength according to claim 3, wherein: the distance between the middle points of two adjacent ceramic layer sheets is 50-80 μm.