Synthesis of LiCoO2 from cobalt—organic acid complexes and its electrode behaviour in a lithium secondary battery

✍ Scribed by Masaki Yoshio; Hirofumi Tanaka; Kenji Tominaga; Hideyuki Noguchi

• Book ID: 103898717
• Publisher: Elsevier Science
• Year: 1992
• Tongue: English
• Weight: 393 KB
• Volume: 40
• Category: Article
• ISSN: 0378-7753
• DOI: 10.1016/0378-7753(92)80023-5

✦ Synopsis

Well-crystallized, layered LiCoO, has been prepared by heating cobalt+rganic acid complexes (such as malic acid and succinic acid) at 900 "C in air after preheating at 400 "C (2 h) and at 650 "C (6 h). LiCoO, obtained by this method shows a high (003) peak intensity and low (104) or ( ) intensities in X-ray diffraction (XRD). The first discharge capacity of LiCoOz obtained from this method in ester-based electrolyte is 132 mA h g-' on cycling between 4.3 and 3.7 V. The value is larger than that obtained by the conventional method. X-ray diffraction studies and open-circuit voltage curves show the presence of at least two types of reaction. A two-phase reaction occurs in the region of 0.71 <x < 1.0 in LiXcO02. The lithiation proceeds as a homogeneous reaction together with expansion of the c-axis in the region of 0.47 <x<O.71. The expansion of the c-axis against dx change at x=0.56 corresponds well with the voltage jump observed in the charge/discharge curves. Experimental Conventional synthesis of LiCo02 Mixtures of Li*CO-, with C&O4 or cOC03 were heated at 900 "C for 20 h in air.