Improvement of electrochemical properties of Li [Ni0.4Co0.2Mn(0.4-x)Mgx]O2-yFy cathode materials at high voltage region

• Published in: Electrochimica acta Vol. 52; no. 4; pp. 1477 - 1482
• Main Authors: SHIN, Ho-Suk, SHIN, Dongwook, SUN, Yang-Kook
• Format: Conference Proceeding Journal Article
• Language: English
• Published: Oxford Elsevier 01-12-2006
• Subjects: Applied sciences; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Exact sciences and technology; Cathode material; Electrode material; Discharge charge cycle; Thermal stability; Surface structure; Coprecipitation; Electrical characteristic; Electrical impedance; Cobalt oxide; Scanning electron microscopy; Chemical precipitation; Cathode; Magnesium oxide; Secondary cell; Fluorides; X ray diffraction; Intercalation compound; Manganese oxides; Morphology; Equivalent circuit; Electric resistivity; Lithion ion batteries; Lithium oxide; Thermal analysis; Interfacial resistance; Carbonate coprecipitation; Lithium secondary batteries; Nickel oxide
• ISSN: 0013-4686; 1873-3859
• DOI: 10.1016/j.electacta.2006.02.048

Spherical Li[Ni0.4Co0.2Mn(0.4-x)Mgx]O2-yFy, (x = ,0.04, y = ,0.08) with phase-pure and well-ordered layered structure have been synthesized by heat-treatment of spherical [Ni0.4Co0.2Mn0.4-xMgx]3O4 precursors with LiOHH20 and LiF salts. The average particle size of the powders was about 10-15 u.m and the size distribution was quite narrow due to the homogeneity of the metal carbonate, [Ni0.4Co0.2Mn(0.4-x)Mgx]CO3 (x = ,0.04) precursors. Although the LifNi0.4Co0.2Mn0.36Mg0.04JO1.92F0.08delivered somewhat slightly lower initial discharge capacity, however, the capacity retention, interfacial resistance, and thermal stability were greatly enhanced comparing to the Li[Ni0.4Co0.2Mn0.4]O2 and Li[Ni0.4Co0.2Mn0.36Mg0.o4]O2.