The diaphragm is an important part of the lithium ion battery, which is an important component that supports the lithium ion battery to complete the charge and discharge electrochemical process. It is located between the positive and negative electrodes of the battery, ensuring that the lithium ion is passed, and the electron transfer is hindered. The performance of the diaphragm determines the interface structure, internal resistance, and the like, which directly affects the capacity, cycle, and safety performance of the battery, and the performance excellent in performance has an important role in improving the overall performance of the battery.

Main role of diaphragm in lithium battery

1, the positive, negative electrode, preventive positive and negative contacts are formed by separating the lithium battery;

2, the micropores in the film can pass the lithium ion to form a charge and discharge circuit

Types of lithium-ion battery diaphragm

Depending on the difference in physical and chemical characteristics, the lithium battery diaphragm can be divided into: woven film, nonwoven film (nonwoven fabric), microporous membrane, composite film, diaphragm paper, rolling film, and the like. Although there is a wide variety of types, the primary lithium battery diaphragm material is mainly used by polyethylene, polypropylene microporous membrane.

Performance requirements of lithium-ion battery diaphragm

1, has electron insulation to ensure the mechanical isolation of the positive and negative electrode;

2, there is a certain aperture and porosity, to ensure that low resistance and high ion conductivity, have good permeability to lithium ions;

3, electrolyte corrosion, there is sufficient chemical and electrochemical stability, which is due to the solvent of the electrolyte as a strongly polar organic compound;

4, has a good infiltration of the electrolyte, and the absorbent moisturizing ability is strong;

5, high mechanical stability, including puncture strength, tensile strength, etc., but thickness as small as possible;

6, spatial stability and good harness;

7, thermal stability and automatic shutdown protection performance;

8, the heat shrinkage rate is small, otherwise it will cause short circuits, which can cause battery thermal failure. In addition, the power battery usually uses a composite film and is higher to the diaphragm.

In a lithium battery, after the separator absorbs the electrolyte, it can be isolated, negative to prevent short circuit, but also allows lithium ions to be conducted. When overcharge or temperature increases, the diaphragm has high temperature self-closing performance to block current transfer to prevent explosion. Not only that, the lithium battery diaphragm has a high strength, fire, chemical reagent, acid and alkali-resistant corrosion, biocompatibility, non-toxic and other characteristics.

ACEY new energy provides different size lithium-ion battery diaphragm, welcome to inquiry.