Lithium-ion Full Cell Manufacturing Process Training--Separator section

1.Role and Selection Criteria of Separators

1.1.Role of Separator

1) The separator is an important component of lithium-ion batteries.

2) Electronic insulation and ionic conductivity.

 

1.2.Requirement of Separator

Characteristics of separators

1)Electronic insulation - mechanical isolation between the positive and negative electrodes;

2)Certain pore sizes and porosity, low resistance and high ionic conductivity, allowing good permeability for lithium ions;

3)Resistant to corrosion by electrolytes, with sufficient chemical and electrochemical stability;

4)Good wettability to electrolytes and sufficient ability to absorb and retain moisture;

5)Sufficient mechanical properties - such as puncture strength and tensile strength, while maintaining as thin a thickness as possible;

6)Good spatial stability and flatness;

7)Excellent thermal stability and automatic shutdown performance;

8)Higher requirements for separators in power batteries, typically using composite membranes.

 

1.3.Main Performance Parameters of Separators