Impedance Track Based Gas Gauge Improves the Gauge Accuracy andExtends the Battery Running Time

摘要

Applications that use battery fuel-gauge apply the reportedstate of charge information in order to preserve data fromloss or corruption. This is done by initiating a shut-downprocedure when remaining capacity drops below certainthreshold (for example 3%). However, if fuel-gauge reportswrong remaining capacity, this shut-down can happen muchearlier when capacity is still available. As a battery ages,commonly used battery algorithms used in gas gauge Icsmay see a dramatic increase in error rate. Aged batteries aremore likely to be under-utilized, and in fact the unusedenergy can be higher than the energy loss from actualphysical performance degradation. This paper looks at theoperating principle of Impedance Track technology forsingle cell Li-Ion battery applications. In addition toimproving gas gauge accuracy a flexible battery terminationvoltage scheme is proposed to extend the battery run-timebased on chemical and useable capacity analysis.