Portable device battery technique

Abstract

When a user has a portable telephone near the absolute end of its available battery power, the user can be caused to behave in a manner that more likely results in the preservation of some battery power for subsequent high priority high priority calls by conveying the illusion that the battery will soon be, or is, depleted even though there actually remains sufficient power in the battery to power the portable telephone for an additional period of time. To this end, at a predetermined time, e.g., two minutes, prior to a projected time at which the battery is expected to have power for only a particular additional amount of time, e.g., eight minutes, the user is signaled with an almost-out-of-power warning. This warning indicates that there remains in the battery enough power to operate the portable telephone only until the projected time, notwithstanding that there actually remains in the battery sufficient power to operate the portable telephone for the additional time beyond the projected time. To enhance the illusion of early battery power depletion, the portable telephone powers off at the projected time. Furthermore, any battery power indicator provides the user with an artificially low power reading that indicates that the battery power will be completely depleted at the projected time. At any point after initiation of the almost-out-of-power warning, the user may take an affirmative action to make available the additional power remaining in the battery. At that point, the display is restored to an accurate indication.