Toward Practical Li-Ion Cells With Li/Mn-Rich Layered Oxide Cathodes: A Techno-Economic Perspective on Material and Cell Design.

Abstract

Li/Mn-rich layered oxide (LMR) cathode active materials offer a pathway towards high specific energy and low-cost Li ion batteries (LIBs) due to their high practical specific discharge capacity (>250 mAh g^-1) at moderate discharge voltages (≈3.5 V). However, oxygen redox requires electrochemical activation at high cathode potentials (> 4.5 V vs Li|Li⁺), resulting in bulk degradation and surface reactivity. This perspective first summarizes the literature-known efforts to elucidate the oxygen redox mechanism and then proposes strategies for systematic R&D of LMR, supported with techno-economic analysis. Initially, bulk degradation should be addressed via compositional tuning and crystal modification. Subsequently, the microstructure, interphase, and electrolyte should be engineered, and finally, the charging protocol should be optimized. The various LMR chemistries with different Li to TM, Ni to Mn, and Co to Ni ratios are techno-economically analyzed, and perspectives on the ideal LMR composition are presented. Ultimately, the specific energy, energy density, and costs of LMR || graphite cells are compared to state-of-the-art cell chemistries.