Citation

Chou LY, Ye Y, Lee HK, Huang W, Xu R, Gao X, Chen R, Wu F, Tsung CK, Cui Y. Nano Lett. 2021; ePub(ePub): ePub.

Copyright

(Copyright © 2021, American Chemical Society)

DOI

10.1021/acs.nanolett.0c04568

PMID

unavailable

Abstract

Safety issues associated with lithium-ion batteries are of major concern, especially with the ever-growing demand for higher-energy-density storage devices. Although flame retardants (FRs) added to electrolytes can reduce fire hazards, large amounts of FRs are required and they severely deteriorate battery performance. Here, we report a feasible method to balance flame retardancy and electrochemical performance by coating an electrolyte-insoluble FR on commercial battery separators. By integrating dual materials via a two-pronged mechanism, the quantity of FR required could be limited to an ultrathin coating layer (4 μm) that rarely influences electrochemical performance. The developed composite separator has a four-times better flame retardancy than conventional polyolefin separators in full pouch cells. Additionally, this separator can be fabricated easily on a large scale for industrial applications. High-energy-density batteries (2 Ah) were assembled to demonstrate the scaling of the composite separator and to confirm its enhanced safety through nail penetration tests.

Language: en

Keywords

fire extinguishing; Flame-retardant separator; lithium-ion battery; ultrathin coating