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arXiv · 2209.02409

Ultra-Low Temperature Li/CFx Batteries Enabled by Fast-transport and Anion-pairing Liquefied Gas Electrolytes

Yijie Yin·John Holoubek·Alex Liu·Baharak Sayahpour·Ganesh Raghavendran·Guorui Cai·Bing Han·Matthew Mayer·Noah B. Schorr·Timothy N. Lambert·Katharine L. Harrison·Weikang Li·Zheng Chen·Y. Shirley Meng
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Abstract

Lithium fluorinated carbon is one of the most promising chemistries for high-energy-density primary energy storage systems in applications where rechargeability is not required. Though Li/CFx demonstrates high energy density under ambient conditions, achieving such a high energy density when exposed to subzero temperatures remains a challenge, particularly under high current density. Here, we report a liquefied gas electrolyte with an anion-pair solvation structure based on dimethyl ether with a low melting point and low viscosity, leading to high ionic conductivity between a wide temperature range. Besides that, through systematic X-ray photoelectron spectroscopy integrated with transmission electron microscopy characterizations, we evaluate the interface of CFx for low-temperature performance. We conclude that the fast transport and anion-pairing solvation structure of the electrolyte bring about reduced charge transfer resistance at low temperatures, which resulted in significantly enhanced performance of Li/CFx cells. Utilizing 50 mg/cm2 loading electrodes, the Li/CFx still displayed 1530 Wh/kg at reduced temperature. This work provides insights into the electrolyte design that may overcome the operational limits of batteries in extreme environments.

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Yijie Yin, John Holoubek, Alex Liu, Baharak Sayahpour, Ganesh Raghavendran, Guorui Cai, Bing Han, Matthew Mayer, Noah B. Schorr, Timothy N. Lambert, Katharine L. Harrison, Weikang Li, Zheng Chen, Y. Shirley Meng. 2022-09-02. Ultra-Low Temperature Li/CFx Batteries Enabled by Fast-transport and Anion-pairing Liquefied Gas Electrolytes. https://arxiv.org/abs/2209.02409

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