context: Against this backdrop, the presently reported work focuses on designing a composition (viz., combination of TM- and non-TM-ions) and suitably tuning some structural features of O3-type Na-TM-oxide based cathode materials to address the main issue concerning stability against hydration and also improve the electrochemical cyclic stability, as well as rate capability. While doing so, a strong correlation between the composition, structure, stability against hydration and electrochemical behavior/performance for such oxides has been established. As will be demonstrated, an air/water-stable (despite long-term exposures under stringent conditions) O3-type Na-TM-oxide has been developed, which is devoid of all the problems mentioned above, so much so that it allows the successful development of stable electrodes using a cost-effective and environment/health friendly ‘water based binder’ (i.e., Na-alginate) and water as solvent during electrode preparation (viz., ‘aqueous processing’). To the best of our knowledge, such excellent stability against hydration and electrochemical performance, despite being ‘aqueous-processed’, have not been reported earlier for O3-type Na-TM-oxide based cathodes.
answer: O3-type Na-TM-oxide based