TY - JOUR
T1 - Chemistry evolution of LiNi1/3Co1/3Mn1/3O2-NaHSO4·H2O system during roasting
AU - Zhang, Xiaodong
AU - Wang, Dahui
AU - Chen, Huaijing
AU - Yang, Lixin
AU - Yu, Yueshan
AU - Xu, Li
N1 - Publisher Copyright:
© 2019 Elsevier B.V.
PY - 2019/10/15
Y1 - 2019/10/15
N2 - LiNi1/3Co1/3Mn1/3O2 is one of the key materials used in power lithium-ion batteries. At present, much attention is put on the study of chemical properties of LiNi1/3Co1/3Mn1/3O2 in acidic aqueous solutions. Different from the acidic aqueous solutions reaction system, this paper presents a study on the chemistry evolution of LiNi1/3Co1/3Mn1/3O2-NaHSO4·H2O system with stoichiometric mass ratio of 1:4.30 during roasting process, which is studied by thermogravimetry-differential scanning calorimetry, in-situ X-ray diffraction, X-ray diffraction and X-ray photoelectron spectroscopy. The experimental results show that the quondam phase composition of the mixture is disappeared and transformed to its corresponding sulfates (LiNaSO4 and Na2Ni(SO4)2 etc.). In the temperature range under 425 °C, the original structure of LiNi1/3Co1/3Mn1/3O2 is completely destroyed due to the lack of Li in the α-NaFeO2 layered structure, and the bimetallic sulfates were transformed and existed in the form of Na2M(SO4)2 (M = Ni, Co, Mn) from 425 °C to 550 °C. The occurrence of Li, Ni, Co, and Mn elements evolves as follows: LiNi1/3Co1/3Mn1/3O2 → Li2SO4 → LiNaSO4, LiNi1/3Co1/3Mn1/3O2 → NiSO4 → Na6Ni(SO4)4 → Na2Ni(SO4)2, LiNi1/3Co1/3Mn1/3O2 → CoSO4 → Na6Co(SO4)4 → Na2Co(SO4)2, LiNi1/3Co1/3Mn1/3O2 → MnO2 → Mn2O3 → MnSO4 → Na2Mn(SO4)2, and the change of valence state of Co and Mn is +3 → +2 and + 4 → +3 → +2, respectively. The chemistry reaction mechanism of this roasting process might be reactions as follows: 12LiNi1/3Co1/3Mn1/3O2 + 36NaHSO4·H2O → 18Na2SO4 + 6Li2SO4 + 4NiSO4 + 4CoSO4 + 4MnSO4 + 54H2O + 3O2, Li2SO4 + Na2SO4 → 2LiNaSO4, MeSO4 + 3Na2SO4 → Na6Me(SO4)4 (Me = Ni, Co), Na6Me(SO4)4 → Na2Me(SO4)2 + 2Na2SO4, MnSO4 + Na2SO4 = Na2Mn(SO4)2.
AB - LiNi1/3Co1/3Mn1/3O2 is one of the key materials used in power lithium-ion batteries. At present, much attention is put on the study of chemical properties of LiNi1/3Co1/3Mn1/3O2 in acidic aqueous solutions. Different from the acidic aqueous solutions reaction system, this paper presents a study on the chemistry evolution of LiNi1/3Co1/3Mn1/3O2-NaHSO4·H2O system with stoichiometric mass ratio of 1:4.30 during roasting process, which is studied by thermogravimetry-differential scanning calorimetry, in-situ X-ray diffraction, X-ray diffraction and X-ray photoelectron spectroscopy. The experimental results show that the quondam phase composition of the mixture is disappeared and transformed to its corresponding sulfates (LiNaSO4 and Na2Ni(SO4)2 etc.). In the temperature range under 425 °C, the original structure of LiNi1/3Co1/3Mn1/3O2 is completely destroyed due to the lack of Li in the α-NaFeO2 layered structure, and the bimetallic sulfates were transformed and existed in the form of Na2M(SO4)2 (M = Ni, Co, Mn) from 425 °C to 550 °C. The occurrence of Li, Ni, Co, and Mn elements evolves as follows: LiNi1/3Co1/3Mn1/3O2 → Li2SO4 → LiNaSO4, LiNi1/3Co1/3Mn1/3O2 → NiSO4 → Na6Ni(SO4)4 → Na2Ni(SO4)2, LiNi1/3Co1/3Mn1/3O2 → CoSO4 → Na6Co(SO4)4 → Na2Co(SO4)2, LiNi1/3Co1/3Mn1/3O2 → MnO2 → Mn2O3 → MnSO4 → Na2Mn(SO4)2, and the change of valence state of Co and Mn is +3 → +2 and + 4 → +3 → +2, respectively. The chemistry reaction mechanism of this roasting process might be reactions as follows: 12LiNi1/3Co1/3Mn1/3O2 + 36NaHSO4·H2O → 18Na2SO4 + 6Li2SO4 + 4NiSO4 + 4CoSO4 + 4MnSO4 + 54H2O + 3O2, Li2SO4 + Na2SO4 → 2LiNaSO4, MeSO4 + 3Na2SO4 → Na6Me(SO4)4 (Me = Ni, Co), Na6Me(SO4)4 → Na2Me(SO4)2 + 2Na2SO4, MnSO4 + Na2SO4 = Na2Mn(SO4)2.
KW - Chemistry evolution
KW - Element occurrence
KW - In-situ XRD
KW - LiNiCoMnO
KW - Roasting
UR - http://www.scopus.com/inward/record.url?scp=85067621186&partnerID=8YFLogxK
U2 - 10.1016/j.ssi.2019.05.018
DO - 10.1016/j.ssi.2019.05.018
M3 - Article
AN - SCOPUS:85067621186
SN - 0167-2738
VL - 339
JO - Solid State Ionics
JF - Solid State Ionics
M1 - 114983
ER -