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

Abstract

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 Nb_1.60Ti_0.32W_0.08O_5-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 LiNi_0.8Mn_0.1Co_0.1O₂-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.