Abstract: A frameless battery cavity formed in a device enclosure retains a battery housing. Cantilever tabs on a battery end of a wall of the device housing have detents that forcibly engage the battery housing when the battery housing is fully inserted into the battery cavity. The detents are restrained from springing away from the battery housing when it is fully inserted by notches in a battery cover. The notches engage the detents after the battery has been fully inserted. The battery cover is secured in the opening to the battery cavity so that the detents are prevented from expanding away from the battery, and thus releasing the battery from the cavity, unless the cover is removed by a user. A guiding mechanism guides the battery housing into the cavity to facilitate electrical engagement of a connection between the battery housing and the device housing.

Abstract: A frameless battery cavity formed in a device enclosure retains a battery housing. Cantilever tabs on a battery end of a wall of the device housing have detents that forcibly engage the battery housing when the battery housing is fully inserted into the battery cavity. The detents are restrained from springing away from the battery housing when it is fully inserted by notches in a battery cover. The notches engage the detents after the battery has been fully inserted. The battery cover is secured in the opening to the battery cavity so that the detents are prevented from expanding away from the battery, and thus releasing the battery from the cavity, unless the cover is removed by a user. A guiding mechanism guides the battery housing into the cavity to facilitate electrical engagement of a connection between the battery housing and the device housing.

Abstract: An algorithm extends the serviceable life of a Li Ion battery by charging a battery to a predetermined percentage of its rated charge capacity. The amount of energy impressed into the battery during charging is determined by periodically measuring the charge energy impressed at a given instance, and integrating the instantaneous energy measurements with respect to time over the charging period. Each time the battery is subsequently recharged, charging the battery to this same amount of energy provides the same amount of energy during discharge. Upon each subsequent recharge following the initial charge, the battery terminal voltage is slightly higher than at the end of the previous recharge. When the terminal voltage measured before the end of a recharge period exceeds the battery's rated voltage, the algorithm ends and indicates that the battery can no longer be used in the given application and should be replaced.