Designing lithium ion batteries for high power applications

Abstract

The capacity of a battery can be predicted from calculation if the specific discharge capacity of the electrode active materials is known. In designing high capacity batteries that would increase the discharge lifetime, the size, thickness and area density of the electrode materials can be optimized. Such design is suitable in the operating temperature range between ambient to 60/spl deg/C. Above 60/spl deg/C, the discharge lifetime decreases quite significantly. It is already known that the transport properties of the conducting species in liquid electrolytes can be improved by the addition of fillers. This will further improve the discharge lifetime and lead to higher specific discharge capacity and specific energy. In the present work, the effects of adding fillers to the electrolyte on the performance of the fabricated batteries with LiCoO/sub 2///MCMB couple were investigated. With LICoO/sub 2///MCMB couple, the fabricated battery can be charged to 4.2 V. The performance of the battery was evaluated for constant discharge currents at different temperatures. It was observed that the discharge capacity of the battery improved with the addition of fillers in the electrolyte. The cells also showed low self-discharge performance.