การพัฒนาสารประกอบลิเทียมโลหะออกไซด์เพื่อเป็นขั้วแคโทดสาหรับแบตเตอรี่ลิเทียมไอออน

Abstract

This research studied the development of the metal oxide compound of lithium chromium manganese oxide for cathode materials. The transition metals are Cr and Mn whic have good cycle stability, higher energy density, high capacity, better cycle life, low cost, and nontoxicity. The two main parts of this study were to find the ratio of Cr:Mn and study the transition metal-doped compounds for cathode development. The study results found that the lithium chromium manganese oxide compound (LiCrxMnyO4; x: y = 1:1, 1:2, 2:1) has been synthesized by two steps solid-state reaction method. The compounds were calcined at 600 °C for 6 h and 900 °C for 12 h in the air. A pure phase was of lithium chromium manganese oxide with a ratio of chromium and manganese equal to 1:1 was successfully synthesized and used to make cathode materials. Besides, the electrochemical behavior of the materials was studied. The first cycle showed the capacity of 46.80 mAh/g while for the 10th cycle the value decreased to 43.50 mAh/g, at 120 °C in vacuum baking of the cathoplatestes. After that, the lithium chromium manganese oxide compound (Cr:Mn = 1:1) with Ni doping (1, 2, 3, 4, and 5 wt.%) was developed in the same synthesizing step, comparing between two different temperatures for vacuum baking of the cathode plates (80, and 120 °C). The synthesized lithium chromium manganese nickle oxide compound (Li2Cr1-0.5xMn1-0.5xNixO4; x = 0.01, 0.02, 0.03, 0.04, and 0.05) has a pure phase in all conditions and small size in the nanometer range. In addition, the lithium chromium manganese nickle oxide compound with Ni 4 wt.% has the highest electrochemical behavior. The first cycle showed the capacity of 72.81 mAh/g, while it decreased to 73.49 mAh/g, respectively, for the 10th cycle at 80 °C in vacuum baking of the cathode plates.