Incorporation of High-Entropy Doped Microregions into 5 V Spinel Oxide for Ultra-Long Cycling Lifespan.

As a leading candidate for high-voltage, cobalt-free cathodes, spinel LiNiMnO (LNMO) oxide is highly attractive for next-generation lithium-ion batteries. However, the instability of cation-oxygen bonds (especially Mn-O) and the adverse two-phase transition of LNMO result in rapid crystal collapse during cycling, thus limiting its practical deployment. To address these issues, herein we exploit the differences in miscibility between dopants and the spinel matrix to embed high-entropy doped microregions (HEDRs, 5-15 nm in size) within the spinel.

Micrometer-scale single crystalline particles of niobium titanium oxide enabling an Ah-level pouch cell with superior fast-charging capability.

Wadsley-Roth phase niobium titanium oxide (TiNbO) is widely regarded as a promising anode candidate for fast-charging lithium-ion batteries due to its safe working potential and doubled capacity in comparison to the commercial fast-charging anode material (lithium titanium oxide, LiTiO). Although good fast charge/discharge performance was shown for nanostructured TiNbO, the small size would cause the low electrode compensation density and energy density of batteries, as well as parasitic reactions. Fundamental understanding of the electrochemical lithium insertion/extraction process and the structural evolution for the micrometer-scale single crystalline TiNbO (MSC-TiNbO) could provide insights to understand its inherent properties and possibility for fast-charging application.