Work

Safe, scalable and reliable solution for solid-state lithium metal polymer batteries

Year: 2025

Type: article

Abstract: Solid-state lithium metal batteries are expected to revolutionize the electric vehicle market due to the safety of the technology as well as their unmatched energy densities. However up to now, the low maturity of the technology and poor electrochemical performance at low temperatures limit its use, mainly due to the poor ionic conductivity and mechanical strength of the solid electrolytes which are usually poly(ethylene oxide) (PEO)-based. In this work, we present ad-hoc formulations of solid-state polymer electrolyte (SPE) and catholyte to obtain a scalable and fire-resistant system with high mechanical integrity and low operating temperature. The proposed SPE is composed by an ethylene oxide (EO) and propylene oxide (PO)-based copolymer, a plasticizer [poly(ethylene glycol) dimethyl ether (PEGDME)] and a cross-linkable polymer [poly(ethylene glycol) diacrylate (PEGDA)] that can block lithium dendrites at 60 ºC. Accordingly, to the proposed SPE, a highly conductive catholyte formulation, composed of Jeffamine® based comb polymer, is introduced in a lithium iron phosphate (LFP) cathode that exhibits high capacities (152 mAh g-1) after 80 cycles at 40 ºC. Furthermore, by fine-tuning the slurry process and formulation a 75 wt. % LFP cathode is scaled up to obtain a proof-of-concept pouch cell capable of delivering 142 mAh g−1 at 40 °C when combined with the developed SPE.

Source: Journal of Energy Storage

DOI: 10.1016/j.est.2025.116547