A method and an apparatus as described for informing a system user of the remaining battery terminal voltage as the battery approaches the fully discharged condition. One horizontal fuel gauge icon (11) for each battery is displayed on the host system display panel (6). The fuel gauge is displayed as two overlapping rectangles which are left justified. The first layer is a solid outline, always the same width, representing the full charge capacity of the battery. The second layer is a filled-in rectangle representing the present (actual) charge capacity as a percentage of the full charge capacity in a charge depletion mode and representing the battery terminal voltage in a voltage mode. The fuel gauging switches from the charge depletion mode to the voltage mode is response to detection of a battery terminal voltage threshold greater than a shutdown voltage threshold. <；IMAGE>；
