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Title: Rechargeable Li/Cl 2 Battery Down to −80 °C
Abstract

Low temperature rechargeable batteries are important to life in cold climates, polar/deep‐sea expeditions, and space explorations. Here, this work reports 3.5–4 V rechargeable lithium/chlorine (Li/Cl2) batteries operating down to −80 °C, employing Li metal negative electrode, a novel carbon dioxide (CO2) activated porous carbon (KJCO2) as the positive electrode, and a high ionic conductivity (≈5–20 mS cm−1from −80 °C to room‐temperature) electrolyte comprised of aluminum chloride (AlCl3), lithium chloride (LiCl), and lithium bis(fluorosulfonyl)imide (LiFSI) in low‐melting‐point (−104.5 °C) thionyl chloride (SOCl2). Between room‐temperature and −80 °C, the Li/Cl2battery delivers up to ≈29 100–4500 mAh g−1first discharge capacity (based on carbon mass) and a 1200–5000 mAh g−1reversible capacity over up to 130 charge–discharge cycles. Mass spectrometry and X‐ray photoelectron spectroscopy probe Cl2trapped in the porous carbon upon LiCl electro‐oxidation during charging. At −80 °C, Cl2/SCl2/S2Cl2generated by electro‐oxidation in the charging step are trapped in porous KJCO2carbon, allowing for reversible reduction to afford a high discharge voltage plateau near ≈4 V with up to ≈1000 mAh g−1capacity for SCl2/S2Cl2reduction and up to ≈4000 mAh g−1capacity at ≈3.1 V plateau for Cl2reduction.

 
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NSF-PAR ID:
10479304
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Materials
ISSN:
0935-9648
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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