Influence of independent variables on recovering electrode material from Lithium-ion batteries via attrition scrubbing

Abstract

Lithium-ion Batteries (LIBs) have mostly replaced other types of batteries in numerous portable devices and electric vehicles due to their numerous advantages. With the continuous increase in the production of those batteries, the number of spent LIBs that have to be disposed of increases as well. Today, many recycling techniques are used for the spent LIBs, and a key problem is the liberation of metals from non-metals. This paper presents the liberation of electrode materials via attrition scrubbing, i.e. the separation of Al and Cu foil from graphite and LiCoO 2 particles, during which we have determined the influence of three independent variables — solid content, impeller speed and attrition time. To this purpose, the tests were carried out according to a central composite design. It showed that in the sample preparation phase, during comminution, 10% of graphite and LiCoO 2 particles separated by sieving (grain size – 0.1 mm) were recovered. The attrition scrubbing was carried out on the grain size of 8/0.1 mm. Results showed that, depending on the testing conditions, it was possible to recover from 49.52 to 82.30 % of graphite and LiCoO 2 particles. All three tested variables showed a significant influence on the attrition scrubbing process, while the impeller speed proved to have the strongest influence. Regarding the interaction of variables, the interaction of the attrition time and the solid content had the strongest influence, while other interactions were significantly less influential. • The attrition scrubbing is effective in liberating LiCoO 2 and graphite. • The Al and Cu foil are contained in grain size coarser than 0.1 mm. • The recovery of LiCoO 2 and graphite by attrition is within 49.56% and 82.30%. • The impeller speed, attrition time and solid content have an influence. • The impeller speed has the most significant influence on attrition.