Electric vehicles powered with large-scale battery packs are gaining popularity as gasoline price soars. Large-scale battery packs usually consist of an estimated 12,000 battery cells connected in series and parallel, which are susceptible to battery cell failures. Currently available battery-management systems are often dedicated to micro-scale batteries based on static configuration, and hence limited to physical processes. As a result, more interactive computations online are required to cope with a large-scale battery-management system are required.
Researchers at the University of Michigan have developed a dynamic reconfiguration framework that monitors, reconfigures, and controls large-scale battery packs online. The framework is built upon a syntactic bypassing mechanism that provides a set of rules for changing the battery-pack configuration, and a semantic bypassing mechanism by which the battery-cell connectivity is reconfigured to recover from a battery-cell failure. In particular, the semantic bypassing mechanism is dictated by constant-voltage-keeping and dynamic voltage- allowing policies. The former policy is effective in preventing unavoidable voltage drops during the battery discharge, while the latter policy is effective in supplying different amounts of power to meet a wide-range of application requirements.
Applications and Advantages
- Monitoring, reconfiguration, and control of large set battery packs online
- Lengthened battery pack operation time due to high resilience to battery cell failures
- Increased level of fault-tolerance as compared to a legacy scheme
- Enhanced applicability and deployability owing to customizability of reconfiguration framework