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Title: Wide-Temperature Electrolytes for Lithium-Ion Batteries

Abstract

Formulating electrolytes with solvents of low freezing points and high dielectric constants is a direct approach to extend the service temperature range of lithium (Li)-ion batteries (LIBs), for which propylene carbonate (PC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), methyl butyrate (MB) are excellent candidates. In this work, we report such low temperature electrolyte formulations by optimizing the content of ethylene carbonate (EC) in the EC-PC-EMC ternary solvent system with LiPF6 salt and CsPF6 additive. An extended service temperature range from 40°C to 60°C was obtained in LIBs with lithium nickel cobalt aluminum mixed oxide (LiNi0.80Co0.15Al0.05O2, NCA) as cathode and graphite as anode. The discharge capacities at low temperatures and the cycle life at room and elevated temperatures were systematically investigated in association with the ionic conductivity and phase transition behaviors. The most promising electrolyte formulation was identified as 1.0 M LiPF6 in EC-PC-EMC (1:1:8 by wt.) with 0.05 M CsPF6, which was demonstrated in both coin cells of graphite||NCA and 1 Ah pouch cells of graphite||LiNi1/3Mn1/3Co1/3O2. This optimized electrolyte enables excellent wide-temperature performances, as evidenced by the 68% capacity retention at 40C and C/5 rate, and nearly identical stable cycle life at room and elevated temperatures up to 60C.

Authors:
; ; ORCiD logo; ORCiD logo; ; ; ORCiD logo; ; ORCiD logo; ORCiD logo
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V)
OSTI Identifier:
1363998
Report Number(s):
PNNL-SA-124731
Journal ID: ISSN 1944-8244; 49321
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: ACS Applied Materials and Interfaces; Journal Volume: 9; Journal Issue: 22
Country of Publication:
United States
Language:
English
Subject:
25 ENERGY STORAGE; wide temperature performance; low temperature discharge; electrolyte; cesium cation; Environmental Molecular Sciences Laboratory

Citation Formats

Li, Qiuyan, Jiao, Shuhong, Luo, Langli, Ding, Michael S., Zheng, Jianming, Cartmell, Samuel S., Wang, Chong-Min, Xu, Kang, Zhang, Ji-Guang, and Xu, Wu. Wide-Temperature Electrolytes for Lithium-Ion Batteries. United States: N. p., 2017. Web. doi:10.1021/acsami.7b04099.
Li, Qiuyan, Jiao, Shuhong, Luo, Langli, Ding, Michael S., Zheng, Jianming, Cartmell, Samuel S., Wang, Chong-Min, Xu, Kang, Zhang, Ji-Guang, & Xu, Wu. Wide-Temperature Electrolytes for Lithium-Ion Batteries. United States. doi:10.1021/acsami.7b04099.
Li, Qiuyan, Jiao, Shuhong, Luo, Langli, Ding, Michael S., Zheng, Jianming, Cartmell, Samuel S., Wang, Chong-Min, Xu, Kang, Zhang, Ji-Guang, and Xu, Wu. Fri . "Wide-Temperature Electrolytes for Lithium-Ion Batteries". United States. doi:10.1021/acsami.7b04099.
@article{osti_1363998,
title = {Wide-Temperature Electrolytes for Lithium-Ion Batteries},
author = {Li, Qiuyan and Jiao, Shuhong and Luo, Langli and Ding, Michael S. and Zheng, Jianming and Cartmell, Samuel S. and Wang, Chong-Min and Xu, Kang and Zhang, Ji-Guang and Xu, Wu},
abstractNote = {Formulating electrolytes with solvents of low freezing points and high dielectric constants is a direct approach to extend the service temperature range of lithium (Li)-ion batteries (LIBs), for which propylene carbonate (PC), ethyl methyl carbonate (EMC), diethyl carbonate (DEC), methyl butyrate (MB) are excellent candidates. In this work, we report such low temperature electrolyte formulations by optimizing the content of ethylene carbonate (EC) in the EC-PC-EMC ternary solvent system with LiPF6 salt and CsPF6 additive. An extended service temperature range from 40°C to 60°C was obtained in LIBs with lithium nickel cobalt aluminum mixed oxide (LiNi0.80Co0.15Al0.05O2, NCA) as cathode and graphite as anode. The discharge capacities at low temperatures and the cycle life at room and elevated temperatures were systematically investigated in association with the ionic conductivity and phase transition behaviors. The most promising electrolyte formulation was identified as 1.0 M LiPF6 in EC-PC-EMC (1:1:8 by wt.) with 0.05 M CsPF6, which was demonstrated in both coin cells of graphite||NCA and 1 Ah pouch cells of graphite||LiNi1/3Mn1/3Co1/3O2. This optimized electrolyte enables excellent wide-temperature performances, as evidenced by the 68% capacity retention at 40C and C/5 rate, and nearly identical stable cycle life at room and elevated temperatures up to 60C.},
doi = {10.1021/acsami.7b04099},
journal = {ACS Applied Materials and Interfaces},
number = 22,
volume = 9,
place = {United States},
year = {Fri May 26 00:00:00 EDT 2017},
month = {Fri May 26 00:00:00 EDT 2017}
}
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