Towards Fire-Safe Polymer Electrolytes for Lithium-Ion Batteries: Strategies for Electrolyte Design and Structural Design

Khang Le Truong; Joonho Bae

doi:10.3390/polym17212828

journal article Open Access Oct 23, 2025

Towards Fire-Safe Polymer Electrolytes for Lithium-Ion Batteries: Strategies for Electrolyte Design and Structural Design

Khang Le Truong Joonho Bae

Polymers Vol. 17 No. 21 pp. 2828 · MDPI AG

View at Publisher Save 10.3390/polym17212828

Abstract

Lithium-ion batteries, widely used in phones and electric vehicles, pose safety concerns due to the flammability of conventional liquid electrolytes, which are prone to ignition under elevated temperatures and mechanical stress, increasing the risk of fire. Polymer electrolytes have been employed as a safer solution thanks to their superior thermal stability and mechanical strength. However, despite these advantages, many polymer matrices pose a fire hazard, limiting their potential. This review assesses recent advances in enhancing the flame retardancy of polymer electrolytes through a variety of strategies, namely the incorporation of flame-retardant additives, the addition of nanoscale fillers to improve thermal resistance, and the design of layered or hybrid polymer membrane structures that function as thermal barriers. This review evaluates the effectiveness of these methods, examining their flame-retardancy as well as their influences on ionic conductivity and overall battery performance. By highlighting recent progress and enduring safety challenges in solid-state batteries, it aims to offer insights for developing lithium batteries with enhanced safety and high performance.

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Details

Published: Oct 23, 2025
Vol/Issue: 17(21)
Pages: 2828
License: View

Authors

K

Khang Le Truong

Department of Physics and Semiconductor Science, Gachon University, Seongnam-si 13120, Republic of Korea

J

Joonho Bae

Department of Physics and Semiconductor Science, Gachon University, Seongnam-si 13120, Republic of Korea

Funding

National Research Foundation of Korea Award: NRF-2021R1A2C1008272

Cite This Article

Khang Le Truong, Joonho Bae (2025). Towards Fire-Safe Polymer Electrolytes for Lithium-Ion Batteries: Strategies for Electrolyte Design and Structural Design. Polymers, 17(21), 2828. https://doi.org/10.3390/polym17212828

Towards Fire-Safe Polymer Electrolytes for Lithium-Ion Batteries: Strategies for Electrolyte Design and Structural Design

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