One is to provide safety guarantee for lithium batteries. Diaphragm material must first have good insulation, in order to prevent the anode contact is short circuit or particle, dendritic spines by burr, wear and short circuit, thus, the diaphragm requires a certain tensile, puncture strength, not easy to tear, and the sudden high temperature under the condition of basic maintain the stability of size and will not melt condensation lead to large area of short circuit and thermal runaway of the battery.



The second is to provide lithium battery to realize the charge and discharge function, rate performance of the microporous channel. Therefore, the diaphragm must be a thin film with high porosity and uniform distribution of micropores. The characteristics of the material itself and the pore characteristics after film formation restrict the migration of lithium ions in the battery, which is reflected in the performance parameter of ion conductivity.



Overview of the production line of lithium battery diaphragm drawing film



This production line model HD/LY1700-3-PP is used to make dry lithium electric diaphragm. The raw material is PP, the roll surface width is 1700, and the film thickness is 10-35μm. The main machine adopts the double-extruding ABA film layer structure into the three-layer compound automatic die, adopts the six-roller drawdown cooling and shaping, equipped with the negative pressure true empty box and the import lock machine device. From drawing forming to double station winding, it adopts low tension design.