PE clapboard is composed of uhmwpe, silicon dioxide, process oil, additive carbon black, antioxidant and so on. The manufacturing process of Pe clapboard is complicated, and it integrates chemical industry, machinery and electronics. In Pe clapboard, silicon dioxide is not only the skeleton of Pe clapboard, but also the pore forming agent of Pe clapboard, accounting for about 60% of the total weight of clapboard. The pore size of Pe clapboard affects the degree of lead dendrite short circuit, the porous structure of the clapboard, the free diffusion of electrolyte and ion migration are allowed, and the resistance and ion conductivity of the clapboard are small. Among many indexes of diaphragm, the porosity of diaphragm is the key index of diaphragm. The porosity of the diaphragm is determined by the pore characteristics of the filler silicon dioxide, so the pore characteristics of the silicon dioxide used in the diaphragm are the key factors affecting the performance of the diaphragm. In addition, the specific surface area of silicon dioxide is required to be 130 ~ 160 M2 / G in the properties of silicon dioxide for PE separators. The silicon dioxide used in PE separators is amorphous silicon dioxide with porous structure, lipophilicity, hydrophilicity, low acid displacement and low impurity content. However, the production technology of PE clapboard silicon dioxide reported in China at present generally exists the problems of complicated operation, large amount of GEL and low yield, the PE separator made by the silicon dioxide also has the disadvantages of high or low specific surface area and low oil absorption value.