Aluminum oxide as a multi-function agent for improving battery performance of LiMn2O4 cathode

Aluminum oxide was used with three different applications to improve battery performance of LiMn2O4 cathode. Indeed, Al2O3 was placed beneath, within and upon the electroactive film. In the first application, aluminum oxide was deposited onto the current collector to strengthen connection of the electroactive material with the substrate surface. In the second one, Al2O3 particles were dispersed within the electroactive film to improve Li intercalation/deintercalation process. And in the last one, Al2O3 was used as a surface-coating agent to cover the spinel surface to avoid Mn dissolution. The influence of these three approaches on the battery performance of LiMn2O4 cathode was examined separately and in combination. The results were indicative of the fact that Al2O3 could be used as a multi-function agent to improve various problems of LiMn2O4 to achieve an acceptable behavior for battery performance. Indeed, it was demonstrated how combination of different methods using a single agent can lead to superiority improvement of the battery performance. The LiMn2O4 cathode prepared based on these three approaches exhibits 1000 charge/discharge cycles at room temperature and 400 cycles at an elevated temperature (55 degreesC), retaining 90% of its initial specific capacity. As Al2O3 is a simple and low-cost agent, the results are of interest for the practical performance. (C) 2004 Published by Elsevier B.V.