The bq2010 Gas Gauge IC is intended for battery-pack or in-system installation to maintain an accurate record of a battery’s available charge. The IC monitors a voltage drop across a sense resistor connected in series between the negative battery terminal and ground to determine charge and discharge activity of the battery.

NiMH and NiCd battery self-discharge is estimated based on an internal timer and temperature sensor. Compensations for battery temperature and rate of charge or discharge are applied to the charge, discharge, and self-discharge calculations to provide available charge information across a wide range of operating conditions. Battery capacity is automatically recalibrated, or "learned," in the course of a discharge cycle from full to empty.

Nominal available charge may be directly indicated using a five- or six-segment LED display. These segments are used to indicate graphically the nominal available charge.Read more