Fault-tolerant battery management system, circuits and methods

Abstract

A fault tolerant battery management system includes redundancy, with applications including electric vehicles. Portions of its circuitry are constituted in distinct fault domains with control, monitoring, and balancing of cells circuitry fault-effect-isolated from the circuitry associated with built-in real-time testing. Built-in tests are orchestrated in fault domains isolated from the functional circuitry being verified. These built-in tests provide test stimulus unique for each cell measurement. Cell balancing is performed in a fault tolerant manner. It takes at least two independent faults, in two mutually distinct fault domains, to negatively affect balancing capability or to interfere with a redundant circuit's ability to operate. The built-in tests allow operation without the requirement for data cross-compare between redundant measuring electronic elements. Testing and balancing functions are interlocked through encoded enabling methodologies and transmit enables on serial buses. The circuitry is divided into mutually fault-isolated modules, each responsible for a subset of the cells.