Transition-Metal Dissolution from NMC-Family Oxides: A Case Study

• Published in: ACS applied energy materials Vol. 3; no. 3; pp. 2565 - 2575
• Main Authors: Morin, Hannah R, Graczyk, Donald G, Tsai, Yifen, Lopykinski, Susan, Iddir, Hakim, Garcia, Juan C, Dietz Rago, Nancy, Trask, Stephen, Flores, LeRoy, Son, Seoung-Bum, Zhang, Zhengcheng, Johnson, Noah M, Bloom, Ira
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 23.03.2020; American Chemical Society (ACS)
• Subjects: corrosion by electrolyte decomposition; corrosion by HF; INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; kinetics; lithium-ion battery; metal dissolution; positive electrode materials; corrosion by electrolyte decomposition; kinetics; lithium-ion battery; corrosion by HF; positive electrode materials; metal dissolution
• ISSN: 2574-0962; 2574-0962
• DOI: 10.1021/acsaem.9b02277

We investigated the static reactions of highly delithiated Li­(Ni1/3Mn1/3Co1/3)­O2, Li­(Ni0.5Mn0.3Co0.2)­O2, Li­(Ni0.6Mn0.2Co0.2)­O2, and Li­(Ni0.8Mn0.1Co0.1)­O2 positive electrodes with 2,3-butanedione and with tetrabutyl ammonium bifluoride as model leaching agents. In the bifluoride trials, it was found that [Ni] in the leachate was proportional to X Co(X Ni)3, where X M is the ideal stoichiometry in the bulk oxide, and inversely proportional to (X Mn)2; [Mn] to X Co(X Ni); and [Co] to X Co. The relationships between metal concentrations and stoichiometry may indicate that nickel, as a next-nearest neighbor on the positive electrode surface, can make dissolution more favorable in some instances.