Researchers have achieved breakthroughs in battery materials and electrolytes, including the development of a quasi-solid 3D-SLISE electrolyte for lithium-ion batteries offering safety and sustainability advancements, and a delocalized electrolyte enhancing lithium metal batteries to achieve 600 Wh/kg energy density. Complementary studies unravel lithium growth mechanisms governed by substrate and electrolyte interfaces, underscoring significant progress towards next-generation energy storage solutions critical for electric vehicles and portable electronics.