<P> Motorola also offered a one - hour desktop charger, though the battery could get quite hot while charging at this accelerated rate . In some cases, this could cause major problems with the battery, occasionally short circuiting it and rendering it unusable . Also, charging the battery at a high enough rate to substantially raise its temperature will cause the battery to wear at an accelerated rate, reducing the number of charge - discharge cycles that can be performed before the battery will need to be replaced . (However, considering the high cost of the DynaTAC, the cost of battery replacement would not typically be a concern to DynaTAC owners .) </P> <P> Available, too, was a snug - fitting zippered leather case which covered the entire body of the phone and had a clear plastic front to make the user interface accessible . It featured a sturdy spring - steel belt clip and a small cutaway at the top to allow the antenna to protrude . Charging could still be performed with the cover on, but change of battery required its removal . </P> <P> Dynatac relates to US phones, used on the Dynatac system in the US, not phones in use in the UK . </P>

When did the first brick phone come out