-d conjugation regulates the cathode/electrolyte interface in all-solid-state lithium-ion batteries

All-solid-state lithium-ion batteries have great scope in the development of advanced secondary batteries owing to their high energy density and nonflammability. However, high contact resistance at the solid/solid (electrode/electrolyte) interface and the possible existence of side reactions limit their large-scale applications. In this study, a pi-d conjugated coordination structure was established between a cathode and electrolyte: 2,5-dihydroxy-1,4-benzoquinone (DHBQ) was the cathode and polyvinylidene fluoride-based Li0.33La0.557TiO3 (PVDF-LLTO) polymer was the solid-state electrolyte. First-principle calculations and performed experiments showed that C00000000000000000000000000000000111111110000000011111111000000000000000000000000O and O-H groups in DHBQ can be coordinated with La3+ in LLTO, and this pi-d conjugate coordination structure strengthens the contact interface between the electrode material and solid electrolyte, which further increases the cycling life and durability of all-solid-state batteries. pi-d Conjugated coordination between the DHBQ electrode and LLTO-PVDF solid electrolyte stabilizes the contact interface.