기계적 혼합과 고상법에 의해 합성한 LiNi1-yMyO2(M=Zn2+, Al3+, and Ti4+)의 전기화학적 특성

Abstract

By calcining at 750℃ for 30 h in O₂ stream after milling, LiNi 1-y M y O₂(M=Zn 2+ , Al 3+ , and Ti 4+ , y=0.005, 0.01, 0.025, 0.05, and 0.1) were synthesized and their electrochemical properties were investigated. All the samples had R3m structure. LiNi 1-y Zn y O₂(y=0.025, 0.05, and 0.1) contained ZnO and/or Li₂ZnO₂ as impurities. Among the samples substituted with the same element, the samples with relatively large value of I 003 /I 104 and the smallest R-factor had the largest first discharge capacity and good cycling performance. LiNi 0.975 Al 0.025 O₂ had the largest first discharge capacity (172.5 mAh/g) and good cycling performance (about 89.4% of the first discharge capacity at the 20th cycle). This sample had the largest value of I 003 I 104 and the smallest R-factor among all the sample. In addition, the particles of this sample were finer and their size was more homogeneous than the other samples. LiNi 0.95 Al 0.05 O₂ had relatively large first discharge capacity 150.4 mAh/g and good cycling performance.