Preparation method of graphene dry powder for LFP (lithium ferric phosphate) anode paste
The invention discloses a preparation method of graphene dry powder for LFP (lithium ferric phosphate) anode paste. The preparation method of graphene dry powder for LFP anode paste comprises the following steps: (1) putting a baked graphene layer into a stirrer, diluting by using NMP (N methyl pyrrolidinone) and stirring at a low speed till the material is at a wet powder state; (2) adding the baked anode active substances of LFP, SP and PVDF (polyvinylidene fluoride) into the graphene wet powder, and stirring continuously at a low speed for 1 2 hours, thereby preparing anode premix; (3) diluting by using NMP, and stirring the anode premix at a low speed till the anode premix is at a wet powder state and the solid content of the premix is 80% 90% (4) diluting the premix at the wet powder state by using NMP until the solid content is around 65% and stirring the premix at a high speed until each component is uniform and dispersive, thereby preparing a mixed material; and (5) beginning to dilute the mixed material when the mixed material generates a pole climbing phenomenon, controlling the solid content of the mixed material to be around 49% and stirring at a high speed so as to prepare the required paste. The preparation method provided by the invention can effectively disperse graphene and each component of other anode materials without adopting any additive for helping the graphene to disperse, and reduces the influence on the battery performance of substances of the type of additives.