Grand challenges in recovery of critical elements from end-of-life lithium-ion batteries (LIBs)

Lithium-ion batteries (LIBs) are widely used for various applications that vary from consumer electronics to national defence in the field of energy storage and batteries. In recent years, hybrid and electric vehicles have become popular owing to which the demand for LIBs has grown exponentially. The elements such as cobalt (Co), nickel (Ni), lithium (Li), and manganese (Mn) are critical components in LIB manufacturing. Moreover, the chemistry and composition of LIB materials vary widely based on applications. The purity requirements of critical materials in the LIB cathodes are >99.9 wt.%. Thus, there is a critical need of high purity battery grade materials, and it is forecasted to increase very significantly. However, the global resources of these materials are limited and are declining rapidly. On the other hand, the widespread applications of LIBs are expected to generate millions of end-of-life LIBs in future years. Considering the growing demand of high purity battery grade materials, the scrap LIBs could be potential source of the critical battery materials. However, the LIB industry lacks a clear path to large scale recycling due to several challenges involved in the recovery of critical materials from end-of-life LIBs. These challenges and potential solutions on those challenges are discussed in this review.