The invention relates to the field of
lithium battery diaphragms, and particularly discloses an
aramid diaphragm for a
lithium battery and a preparation method of the
aramid diaphragm. The
aramid diaphragm for the
lithium battery comprises aramid
slurry and a base membrane, the aramid
slurry is coated on two sides of the base membrane to form an aramid
coating, and the aramid
slurry is prepared from the following raw materials in parts by weight: 20-40 parts of aramid
polymer liquid, 5-10 parts of tencel
fibrillation slurry, 1-3 parts of
titanium aluminum
lithium phosphate nanoparticles, 3-5 parts of nano
ceramic particles and 8-15 parts of
solvent; the aramid
polymer liquid is prepared from the following raw materials in parts by weight: 1 to 3 parts of p-phenylenediamine, 60 to 80 parts of polar
solvent, 5 to 10 parts of paraphthaloyl
chloride, 1 to 3 parts of 3, 4 '-
diaminodiphenyl ether, 1 to 3 parts of o-chloro-p-phenylenediamine and 0.5 to 1 part of polyether surfactant; the aramid
polymer liquid is combined with the nano
ceramic particles and the tencel
fibrillation slurry component to form an intercommunicated porous three-dimensional
network structure, so that the air permeability, the
thermal stability and the
porosity of the aramid diaphragm are improved.