Nb1.60Ti0.32W0.08O5−δ as negative electrode active material for durable and fast-charging all-solid-state Li-ion batteries

Li-based all-solid-state batteries (ASSBs) are considered feasible candidates for the development of the next generation of high-energy rechargeable batteries. However, ASSBs are detrimentally affected by a limited rate capability and inadequate performance at high currents. To circumvent these issues, here we propose the use of Nb1.60Ti0.32W0.08O5-δ (NTWO) as negative electrode active material. NTWO is capable of overcoming the limitation of lithium metal as the negative electrode, offering fast-charging capabilities and cycle stability. Physicochemical and electrochemical characterizations of NTWO in combination with the Li6PS5Cl (LPSCl) solid-state electrolyte demonstrate that the formation of LiWS2 at the electrode|electrolyte interphase is the main responsible for the improved battery performance. Indeed, when an NTWO-based negative electrode and LPSCl are coupled with a LiNbO3-coated LiNi0.8Mn0.1Co0.1O2-based positive electrode, the lab-scale cell is capable of maintaining 80% of discharge capacity retention after 5000 cycles at 45 mA cm−2 at 60 °C and 60 MPa.