Evaluating electrolyte additives for lithium-ion cells: A new Figure of Merit approach

JOURNAL OF POWER SOURCES

卷:365

Article

Tornheim, Adam¹  Peebles, Cameron¹  Gilbert, James A.¹  Sahore, Ritu¹  Garcia, Juan C.¹  Bareno, Javier¹  Iddir, Hakim¹  Liao, Chen¹  Abraham, Daniel P.¹ 

[1] Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA

关键词: Capacity fade;    Impedance rise;    Energy density;    Power density;    Lithium-ion;    Full cells;   

DOI  :  10.1016/j.jpowsour.2017.08.093

来源: Elsevier

【 摘 要 】

Electrolyte additives are known to improve the performance of lithium-ion cells. In this work we examine the performance of Li1.03Ni0.5Mn0.3Co0.3O2-graphite (NMC532/Gr) cells containing combinations of lithium bis(oxalate)borate (LiBOB), vinylene carbonate (VC), trivinylcyclotriboroxane (tVCBO), prop-1ene-1,3-sultone (PES), phenyl boronic acid ethylene glycol ester (PBE), tris(trimethylsilyl) phosphite (TMSPi), triethyl phosphite (TEPi), and lithium difluoro(oxalate)borate (LiDFOB) added to our baseline (1.2 M LiPF6 in EC:EMC, 3:7 w/w) electrolyte. In order to rank performance of the various electrolytes, we developed two separate figures of merit (FOM), which are based on the energy retention and power retention of the cells. Using these two metrics in conjunction, we show that only one of the fifteen electrolyte formulations tested significantly outperforms the baseline electrolyte: this electrolyte contains the 0.25 wt% tVCBO + 1 wt% TMSPi additive mix. Little correlation was observed between the FOMs for energy retention and power retention, which indicates that the mechanisms that govern these performance parameters are likely independent of each other. Our FOM approach has general applicability and can be used to develop electrolyte and electrode formulations that prolong the life of lithium ion batteries. (C) 2017 Elsevier B.V. All rights reserved.

【 授权许可】

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