The main function of the lithium battery separator is to separate the positive and negative electrodes of the battery to prevent short circuit due to contact between the two electrodes, and also has the function of allowing electrolyte ions to pass through. The separator material is non-conductive, and its physical and chemical properties have a great impact on the performance of the battery. Different types of batteries use different separators. For the lithium battery series, since the electrolyte is an organic solvent system, a separator material resistant to organic solvents is required, and a high-strength thin-film polyolefin porous membrane is generally used.

5. PE is more sensitive to environmental stress.