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Title: Porous Polymer Gel Electrolytes Influence Lithium Transference Number and Cycling in Lithium-Ion Batteries
To improve the energy density of lithium-ion batteries, the development of advanced electrolytes with enhanced transport properties is highly important. Here, we show that by confining the conventional electrolyte (1 M LiPF6 in EC-DEC) in a microporous polymer network, the cation transference number increases to 0.79 while maintaining an ionic conductivity on the order of 10−3 S cm−1. By comparison, a non-porous, condensed polymer electrolyte of the same chemistry has a lower transference number and conductivity, of 0.65 and 7.6 × 10−4 S cm−1, respectively. Within Li-metal/LiFePO4 cells, the improved transport properties of the porous polymer electrolyte enable substantial performance enhancements compared to a commercial separator in terms of rate capability, capacity retention, active material utilization, and efficiency. These results highlight the importance of polymer electrolyte structure–performance property relationships and help guide the future engineering of better materials.  more » « less
Award ID(s):
1706370
PAR ID:
10233131
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Electronic Materials
Volume:
2
Issue:
2
ISSN:
2673-3978
Page Range / eLocation ID:
154 to 173
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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