The invention relates to a method for preparing a
lithium iron phosphate / carbon
composite material of a
lithium ion battery, which belongs to the technical field of
lithium ion batteries. The method for preparing the
lithium iron phosphate / carbon
composite material of the
lithium ion battery comprises the following steps of: 1) preparing a suspending
graphene-dispersed
aqueous solution system, namely, crushing
graphite to 1 to 5 microns, adding the crushed
graphite into
distilled water or
purified water, adding 0.1 to 5 percent of surfactant, heating with stirring the
mixed solution to 180 to 250 DEG C in a sealing way, performing stirring for 2 to 6 hours and reducing the temperature; 2) crushing
lithium iron phosphate to the particle size of 1 to 5 microns, adding the crushed
lithium iron phosphate into the
distilled water or the
purified water, adding with stirring 0.01 to 1 percent of
coupling agent, performing uniform stirring, adding the
graphene-dispersed
aqueous solution, and performing stirring and
filtration; and 3) vacuum-
drying solid powder obtained by the
filtration, and calcinating the dried
solid powder for 2 to 12 hours to obtain the
graphene-coated lithium
iron phosphate cathode material. The method has the advantages of simple process, high material performance,
high conductivity, high
bulk density, high compacted density and the like.