CPS:Small: Imposing Recovery Period for Battery Health Monitoring, Prognosis, and Optimization

Abstract: The prevalence of battery-powered systems such as electric vehicles, smartphones, and IoT devices has made batteries crucial to everyone's daily life and business. Battery health, however, degrades over time, not only decreasing system reliability such as unexpected system shutoffs, but also causing overheating/gassing which, in turn, increases safety risks such as thermal runaway or even battery fire/explosion. To address these problems, we must monitor, prognose, and optimize battery health throughout the physical system life. However, existing battery management systems (BMSes) are usually treated as complementary system components attached/embedded to/in batteries, and are unable to make optimal health management decisions adaptively based on system dynamics or user requirements. Our approach tightly integrates the cyber (battery management software) and the physical (sensing of battery state) to enable significant improvements in battery life and performance. The research, outreach, and education activities of this project will have broader impacts on the CPS research and industry communities, bridging the gap between them, providing environment-friendly solutions, increasing the awareness of CPS, and developing skilled human resources. It will also make significant economical and environmental impacts by enabling longer battery life and improved performance. This project will develop R-AWARE, a recovery period-assisted battery health management that schedules system operation while considering both system/user requirements and battery health. R-AWARE will improve battery health via relaxation-aware battery scheduling of battery charging/discharging, and recovery-based thermal control. It will advance the science of CPS by uncovering a thorough understanding of battery recovery and exploiting it via a recovery-aware scheduler during system operation. Specifically, R-AWARE is grounded on a thorough understanding of the physical recovery effects on battery health -- a new dimension for system optimization existing BMSes fail to exploit. R-AWARE then takes a cyber-physical approach for battery health management by adapting its decisions based on various physical properties of batteries/systems/environment. Finally, R-AWARE improves battery health by exploiting the opportunities offered by user behavior/requirements without degrading user experience. A performance goal of the project is to enable a 40% slowdown in battery health degradation.