New insights into lithium-ion battery failure mechanism

Science Daily  August 25, 2020
Ni-rich layered cathode materials are among the most promising candidates for high-energy-density Li-ion batteries, yet their degradation mechanisms are still poorly understood. Researchers in the UK found that as the battery materials expand and shrink the lithium ions move in and out. With prolonged use the atoms at the surface of the material had rearranged to form new structures that are no longer able to store energy. The areas of reconstructed surface apparently act as stakes that pin the rest of the material in place and prevent it from the contraction which is required to reach the fully charged state. As a result, the lithium remains stuck in the lattice and this fatigued material can hold less charge. The researchers are now seeking effective countermeasures, such as protective coatings and functional electrolyte additives, to mitigate this degradation process and extend the lifetime of such batteries…read more. TECHNICAL ARTICLE