Lifetime Improvement by Battery Scheduling

The use of mobile devices is often limited by the lifetime of their batteries. For devices that have multiple batteries or that have the option to connect an extra battery, battery scheduling, thereby exploiting the recovery properties of the batteries, can help to extend the system lifetime. Due to the complexity, work on battery scheduling in literature is limited to either small batteries or to very simple loads. In this paper, we present an approach using the Kinetic Battery Model that combines real size batteries with realistic random loads. The results show that, indeed, battery scheduling results in lifetime improvements compared to the sequential useage of the batteries. The improvements mainly depend on the ratio between the average discharge current and the battery capacity. Our results show that for realistic loads one can achieve up to 20% improvements in system lifetime by applying battery scheduling.