A gradient oxy-thiophosphate-coated Ni-rich layered oxide cathode for stable all-solid-state Li-ion batteries.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 36627277.
- Also identified by DOI 10.1038/s41467-022-35667-7 and PMC identifier 9832028.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
High-energy Ni-rich layered oxide cathode materials such as LiNi<sub>0.8</sub>Mn<sub>0.1</sub>Co<sub>0.1</sub>O<sub>2</sub> (NMC811) suffer from detrimental side reactions and interfacial structural instability when coupled with sulfide solid-state electrolytes in all-solid-state lithium-based batteries. To circumvent this issue, here we propose a gradient coating of the NMC811 particles with lithium oxy-thiophosphate (Li<sub>3</sub>P<sub>1+x</sub>O<sub>4</sub>S<sub>4x</sub>). Via atomic layer deposition of Li<sub>3</sub>PO<sub>4</sub> and subsequent in situ formation of a gradient Li<sub>3</sub>P<sub>1+x</sub>O<sub>4</sub>S<sub>4x</sub> coating, a precise and conformal covering for NMC811 particles is obtained. The tailored surface structure and chemistry of NMC811 hinder the structural degradation associated with the layered-to-spinel transformation in the grain boundaries and effectively stabilize the cathode|solid electrolyte interface during cycling. Indeed, when tested in combination with an indium metal negative electrode and a Li<sub>10</sub>GeP<sub>2</sub>S<sub>12</sub> solid electrolyte, the gradient oxy-thiophosphate-coated NCM811-based positive electrode enables the delivery of a specific discharge capacity of 128 mAh/g after almost 250 cycles at 0.178 mA/cm<sup>2</sup> and 25 °C.