ABSTRACT Anode‐free solid polymer electrolytes (AF‐SPEs) offer a compelling route to maximize cell‐level energy density while improving safety, cost, and manufacturability by replacing the anode with a bare current collector and leveraging ultrathin, low‐density polymer membranes. This review explores key design strategies for optimizing SPE performance in anode‐free lithium metal batteries (AFLMBs), focusing on their role in regulating lithium deposition, enhancing interfacial stability, and improving electro‐chemo‐mechanical robustness. It also examines the fundamental strategies for enhancing the performance of AF‐SPEs, including polymer chemistry, interfacial engineering, and full‐cell lithium inventory management. The review provides insights into the potential of AF‐SPEs to maximize the cell‐level energy density as well as to drive the commercialization of high‐performance, anode‐free solid‐state batteries.
Liu et al. (2026) studied this question.