CN207217640U

CN207217640U - A kind of lithium-ion-power cell multilayer composite membrane

Info

Publication number: CN207217640U
Application number: CN201720496578.XU
Authority: CN
Inventors: 陈晓宁; 郎晓黎; 李维; 陈怀友; 张道发; 李国芳
Original assignee: Individual
Current assignee: Individual
Priority date: 2017-05-07
Filing date: 2017-05-07
Publication date: 2018-04-10
Anticipated expiration: 2027-05-07

Abstract

The utility model discloses a kind of lithium-ion-power cell multilayer composite membrane, with five-layer structure, including polymethyl methacrylate internal layer, respectively in the first polyethylene middle layer and the second polyethylene middle layer of polymethyl methacrylate internal layer both sides, and the first ceramic oxide outer layer and the second ceramic oxide outer layer on the outside of the first polyethylene middle layer and the second polyethylene middle layer respectively, polymethyl methacrylate internal layer has 5 40nm endoporus, first polyethylene middle layer and the second polyethylene middle layer have 20 50nm mesopore, first ceramic oxide outer layer and the second ceramic oxide outer layer have 2 30nm exit orifice, the endoporus, mesopore and exit orifice are not corresponded and are not mutually communicated.The beneficial effects of the utility model：Multilayer composite membrane has the advantages that higher mechanical strength, excellent electrical conductivity, heat-resist, safe.

Description

A kind of lithium-ion-power cell multilayer composite membrane

Technical field

It the utility model is related to lithium battery diaphragm technical field, more particularly to a kind of lithium-ion-power cell MULTILAYER COMPOSITE Barrier film.

Background technology

The battery core of lithium battery is mainly made up of positive electrode, negative material, electrolyte and barrier film, and barrier film is the important of battery core Part, the main function of barrier film are to separate positive pole and negative pole, prevent two-stage from contacting and short-circuit, in addition, also with making electrolysis The function that matter ion passes through, the performance of barrier film determine the interfacial structure of battery, internal resistance etc., directly affect the capacity of battery, follow The characteristic such as ring and security performance.But the preparation of current lithium battery still has hidden danger, and explosive incident happens occasionally, peace Full property and durability have much room for improvement.

Nano fiber diaphragm is an important development direction of novel lithium ion battery diaphragm, national materials many in recent years Material researcher attaches great importance to it.Nano fibrous membrane has the characteristics of specific surface area is big, porosity is high, uniform pickup electrolyte And the electrical property and security of battery can be significantly improved, its weak point is that preparation efficiency is relatively low and mechanical strength is weaker.

And vehicle lithium-ion power battery and lithium-ion energy storage battery propose very high requirement to diaphragm material, such as compared with It is strong absorbent, good by heat endurance, uniform hole, good thickness evenness etc..It is accordingly, it is desirable to provide a kind of Meet the Novel lithium ion power battery diaphragm material of above-mentioned requirements.

Utility model content

Therefore, the utility model proposes a kind of lithium-ion-power cell multilayer composite membrane, it can solve the problem that this area Middle power battery diaphragm internal resistance is big, mechanical strength is low, heat resistance and the problems such as imbibition ability difference.

To realize above-mentioned technical purpose, what the technical solution of the utility model was realized in：

A kind of lithium-ion-power cell multilayer composite membrane, it has five-layer structure, including polymethyl methacrylate Internal layer, respectively in the first polyethylene middle layer of polymethyl methacrylate internal layer both sides and the second polyethylene middle layer and The first ceramic oxide outer layer and the second ceramic oxygen on the outside of the first polyethylene middle layer and the second polyethylene middle layer respectively Compound outer layer, polymethyl methacrylate internal layer have a 5-40nm endoporus, in the first polyethylene middle layer and the second polyethylene Interbed has 20-50nm mesopore, and the first ceramic oxide outer layer and the second ceramic oxide outer layer have 2-30nm exit orifice, The endoporus, mesopore and exit orifice are not corresponded and are not mutually communicated.

Preferably, the porosity of lithium-ion-power cell multilayer composite membrane is 40 ~ 70%.

Preferably, polymethyl methacrylate internal layer thickness is 5 ~ 20 microns.

Preferably, the first polyethylene middle layer and the second polyethylene middle layer thickness are 3 ~ 15 microns.

Preferably, the first ceramic oxide outer layer and the second ceramic oxide outer layer thickness are 1 ~ 10 micron.

The utility model has advantages below：

1st, composite diaphragm uses five-layer structure, effectively increases mechanical strength, improves paracentesis resistance, and then improve electricity The security in pond；

2nd, each layer uses the hole of different pore size, so as to improve imbibition ability, and then reduces internal resistance；

3rd, because the hole of each layer does not penetrate, so as to improve electrolyte retention, the ionic conduction of barrier film is improved Ability.

Brief description of the drawings

Fig. 1 is a kind of lithium-ion-power cell multilayer composite membrane section knot according to the utility model embodiment Structure schematic diagram.

Embodiment

The utility model is described more fully referring to Fig. 1, wherein illustrating exemplary reality of the present utility model Apply example.

As shown in figure 1, a kind of lithium-ion-power cell multilayer composite membrane described in the utility model embodiment, it has Have a five-layer structure, including polymethyl methacrylate internal layer 1, respectively in the first poly- second of polymethyl methacrylate internal layer both sides The polyethylene middle layer 3 of alkene intermediate layer 2 and second and respectively outside the first polyethylene middle layer 2 and the second polyethylene middle layer 3 The the first ceramic oxide outer layer 4 and the outer layer of the second ceramic oxide 5 of side, polymethyl methacrylate internal layer 1 have 5-40nm Endoporus, the first polyethylene middle layer 2 and the second polyethylene middle layer 3 have 20-50nm mesopore, the first ceramic alumina beyond the region of objective existence The ceramic oxide outer layer 5 of layer 4 and second has 2-30nm exit orifice, and the endoporus, mesopore and exit orifice do not correspond and not phase Mutually insertion.The porosity of lithium-ion-power cell multilayer composite membrane is 40 ~ 70%, the thickness of polymethyl methacrylate internal layer 1 For 5 ~ 20 microns.First polyethylene middle layer 2 and the thickness of the second polyethylene middle layer 3 are 3 ~ 15 microns.First ceramic oxide The thickness of 4 and second ceramic oxide outer layer of outer layer 5 is 1 ~ 10 micron.

Composite diaphragm uses five-layer structure, effectively increases mechanical strength, improves paracentesis resistance, and then improve battery Security.Each layer uses the hole of different pore size, so as to improve imbibition ability, and then reduces internal resistance.The hole of each layer is not passed through It is logical, electrolyte retention is improved, improves the ion conductivity of barrier film.Lithium-ion-power cell MULTILAYER COMPOSITE every Film, there is higher mechanical strength, excellent electrical conductivity, heat-resist, safe.

Above content is only preferred embodiment of the present utility model, for one of ordinary skill in the art, according to this reality With new thought, there will be changes, this specification content should not be construed as in specific embodiments and applications To limitation of the present utility model.

Claims

1. a kind of lithium-ion-power cell multilayer composite membrane, it has in five-layer structure, including polymethyl methacrylate Layer, respectively in the first polyethylene middle layer and the second polyethylene middle layer, Yi Jifen of polymethyl methacrylate internal layer both sides The first ceramic oxide outer layer and the second ceramic alumina not on the outside of the first polyethylene middle layer and the second polyethylene middle layer Beyond the region of objective existence layer, it is characterised in that：

Polymethyl methacrylate internal layer has 5-40nm endoporus, the first polyethylene middle layer and the second polyethylene middle layer tool There is 20-50nm mesopore, the first ceramic oxide outer layer and the second ceramic oxide outer layer have 2-30nm exit orifice, described interior Hole, mesopore and exit orifice are not corresponded and are not mutually communicated.

2. lithium-ion-power cell multilayer composite membrane according to claim 1, wherein, the lithium-ion-power cell It is 40 ~ 70% with the porosity of multilayer composite membrane.

3. lithium-ion-power cell multilayer composite membrane according to claim 1, wherein, the poly-methyl methacrylate Ester internal layer thickness is 5 ~ 20 microns.

4. lithium-ion-power cell multilayer composite membrane according to claim 1, wherein, among first polyethylene Layer and the second polyethylene middle layer thickness are 3 ~ 15 microns.

5. lithium-ion-power cell multilayer composite membrane according to claim 1, wherein, first ceramic oxide Outer layer and the second ceramic oxide outer layer thickness are 1 ~ 10 micron.