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Title: Natural protein as novel additive of a commercial electrolyte for Long-Cycling lithium metal batteries
Suffering from critical instability of lithium (Li) anode, the most commercial electrolytes, carbonate-ester electrolytes, have been restrictedly used in high-energy Li metal batteries (LMBs) despite of their broad implementation in lithium-ion batteries. Here, abundant, natural corn protein, zein, is exploited as a novel additive to stabilize Li anode and effectively prolong the cycling life of LMBs based on carbonate-ester electrolyte. It is discovered that the denatured zein is involved in the formation of solid electrolyte interphase (SEI), guides Li+ deposition and repairs the cracked SEI. In specific, the zein-rich SEI benefits the anion immobilization, enabling uniform Li+ deposition to diminish dendrite growth; the preferential zein-Li reaction effectively repairs the cracked SEI, protecting Li from parasite reactions. The resulting symmetrical Li cell exhibits a prolonged cycling life to over 350 h from <200 h for pristine cell at 1 mA cm􀀀 2 with a capacity of 1 mAh cm^ 2. Paired with LiFePO4 cathode, zein additive markedly improves the electrochemical performance including a higher capacity of 130.1 mAh g^ 1 and a higher capacity retention of ~ 80 % after 200 cycles at 1 C. This study demonstrates a natural protein to be an effective additive for the most commercial electrolytes for advancing performance of LMBs.  more » « less
Award ID(s):
1929236
NSF-PAR ID:
10349896
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Chemical engineering journal
Volume:
437
ISSN:
1385-8947
Page Range / eLocation ID:
135283
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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