The invention discloses a battery and
capacitor diaphragm
filter material formed by wet nonwoven fabrics and a preparation method of the
filter material. The
fiber materials are as follows in percentage by weight: 0.1%-2.5% of
plant fibers and 80%-99.9% of synthetic fibers, inorganic
powder being 45%-1000% of the weight of the
fiber, organic
powder being 0-50% of the weight of the fibers, and strengthening binder being 0.5%-15% of the weight of the fibers. The preparation method of the
filter material comprises the following steps of: pulping the
plant fiber and the synthetic fibers, respectively; homogenizing and mixing the inorganic
powder with the organic powder under
high pressure, and forming the mixture into a single layer or a plurality of
layers by a mixer;
coating, thermally rolling and modifying the mixture, so that various physical and chemical indexes of the diagram are improved, the
pore diameter size can be effectively controlled and the uniformity of the
pore diameter is improved; moreover, treelike crystals can be prevented from being generated by maze type bent holes; the filtering precision and the efficiency are high; the inner resistance of the diagram is high; the liquid retaining rate and the high
temperature resistance of the diagram are improved; the over-temperature closed-
cell protection is improved; the dimension deformation is small; the service life is long; and the
economic benefits and the
social benefits are better.