A TEA-starch combustion method for the synthesis of fine-particulate LiMn2O4

Solution combustion synthesis of fine-particulate LiMn2O4 was carried out with triethanolamine (TEA) and starch as fuels. TEA:starch ratio, calcination temperature and duration of calcination were varied in order to obtain LiMn2O4 with optimal electrochemical properties. Increasing the starch content in the precursor was found to be detrimental to product characteristics. Although the product prepared with a TEA:starch ratio of 1:1 by a 10 h calcination at 800 °C showed the highest first-cycle capacity (127 mAh g−1), the cyclability was the highest for the product synthesized by a 500 °C 10 h calcination of a 1:1 TEA:starch precursor. The latter sample sustained 75 cycles at a 0.1C rate between 3.0 and 4.3 V before reaching 80% capacity retention. The electrochemical properties of the products are explained in terms of their structural and morphological properties as well as the local reaction environments during the formation processes.