An evaluation methodology for the Li-Ion battery multiplexed voltage measurement systems
Résumé
In modern era the utilization of battery empowered systems is growing exponentially. In the goal to achieve an optimal system performance, the employment of a BMS (Battery Management System) is inevitable. Data acquisition is an elementary operation of the BMS. Usually a battery is composed of several cells. Therefore, a multiplexed ADC (A/D Converter) is employed for acquiring each cell data. It renders an effective solution in terms of cost and power consumption. However, the multiplexing can render A/D conversion latencies. In this context a performance comparison between two multiplexed data acquisition systems, based respectively on the SigmaDelta and the SAR (Successive Approximation Register) ADCs is made. The application is to measure the Li-Ion battery voltage. A measurement methodology is presented. The pros and cons of both considered systems are described with the experimental results.