Method of preparing battery grade lithium hydroxide from active waste of lithium ion battery anode

The invention provides a method of preparing battery grade lithium hydroxide from active waste of a lithium ion battery anode. The method comprises the following steps: processing the active waste ofthe lithium ion battery anode by an oxidized acid soaking method to form an acid extract, performing two-step extraction, regulating a pH (potential of hydrogen) value of a solution to separate manganese, cobalt and nickel to achieve comprehensive recovery of valuable metals and deep removal of foreign particles of elements such as Fe, Ni, Ca, Mg, Cu and Al, avoiding the loss of lithium effectively in the process, performing deep purification treatment on extraction raffinate with strong-acid cation exchange resin to form a purified lithium-rich solution, treating the purified lithium-rich solution by a bipolar membrane electrodialysis method to form a lithium hydroxide solution and an acid solution, and performing evaporation and concentration on the lithium hydroxide solution to form thebattery grade lithium hyd