Lithium-Ion Battery Cation Separation

Author: Anna Siekierka

Method of separating a mixture of lithium,
cobalt and nickel cations in lithium-ion battery
solutions
The proposed novel solution involves selective fractionation of transition metal ions from
battery effluent via ultra-selective cation exchange membranes under an external electrical
field. It combines selective electrodialysis and an intensified precipitation process (Fig.1B). In
the first stage, the Co, Ni and Li solution is separated via ED using a membrane modified by 5-
chloro-8-hydroxyquinoline (Fig.1A). The electrodialysis process is conducted at least 5 V until
the equilibrium state of ion exchange between the evaluated cationic membrane occurs or
until the ion exchange is inhibited with access to the anionic exchangeable membrane as a
result of the selected cobalt cation transfer from the feed to the permeate chamber and cobalt
cations diffuse in the permeate chamber. Next, the separated solutions were precipitated to
occur in the transition between metal salts and lithium solution. Individuals use hydroxide or
sulfide, sulfate, phosphate, carbonate, silicate, or chromate as precipitants.

Figure 1. The stack of selective ED (a) and strategy of fractionation battery effluents (b).