Carbonate‐ Versus Hydroxide‐Based Precursor for the Synthesis of Li/Mn Rich Cathodes: Exploring Differences in Discharge Capacities and Cycle Life

Lithium/manganese‐rich (LMR)‐based cathodes can enhance the specific energy of Li ion batteries and are conventionally synthesized via a carbonate‐based precursor (LMR‐CO 3 ). The CO 2 evolution‐related voids and enhanced surface area can be avoided by calcination of a hydroxide‐based precursor [LMR‐(OH) 2 ]. This way, the LMR releases less oxygen during charge, as seen by a decreased Mn 3+/4+ redox activity and decreased voltage fade. However, the lower specific discharge capacity is attributed to a decreased lithiation amount in the initial cycles for LMR‐(OH) 2 and is related to a higher Li + extraction degree, that is, a higher redox oxidation number at the discharged state. Interestingly, this decreases the accompanying amount of detrimental Mn 3+ and is concluded to improve cycle life, due to, for example, minimized Jahn–Teller distortions and disproportionation reactions. The differences in lithiation (e − + Li + ) degrees of the two LMRs emerge at end‐of‐discharge and can stem from differences in either redox resistance and/or resistance of Li + intercalation, for example, due to slight crystal stacking faults in the course of different synthesis conditions and/or simply from bigger particle sizes.