Creating high-capacity long-life batteries

Science Daily May 16, 2019
Lithium- and sodium-rich layered transition-metal oxides have large capacity because of additional oxygen-redox reactions. However, they exhibit structural degradation such as cation migration, layer exfoliation or cracks upon deep charge. An international team of researchers (Japan, Spain, France) has demonstrated a self-repairing phenomenon of stacking faults upon desodiation from an oxygen-redox layered oxide Na2RuO3. The phase transformations upon charging A2MO3 can be dominated by three-dimensional Coulombic attractive interactions driven by the existence of ordered alkali-metal vacancies, leading to counterintuitive self-repairing of stacking faults. The vacancy in lithium-/sodium-rich layered transition-metal oxides is shown to play an essential role in generating the electro-active nonbonding and stabilizing the phase transformation…read more. Open Access TECHNICAL ARTICLE