Various types of amorphous Li-Fe-P-B-O were investigated for use as a cathode material. The samples were prepared by the melt quench technique with a single roll. The samples had monotonically decreasing charge-discharge profiles peculiar to amorphous materials, and were between 76 and 119 mAh g-1. The electrochemical performance of these amorphous Li-Fe-P-B-O materials improved with increasing boron ratio, improving from 85 to 119 mAh g-1. Although the redox potentials of amorphous Li-Fe-P-O did not shift with changing P/Fe ratio, those of amorphous Li-Fe-P-B-O did shift with changing B/P ratio. The redox potentials of the Li-Fe-P-B-O in the ratios of 2/1/2/0, 2/1/1/1, 2/1/0.5/1.5, and 2/1/0/2 were approximately 3.1, 2.9, 2.6, and 2.2 V vs. Li/Li+, respectively. This demonstrates that the redox potentials of amorphous polyanionic materials can be tuned by adjusting the electronegativity of the glass former, such as phosphorus and boron.
All Science Journal Classification (ASJC) codes
- Renewable Energy, Sustainability and the Environment
- Energy Engineering and Power Technology
- Physical and Theoretical Chemistry
- Electrical and Electronic Engineering