  We investigate the dynamical formation and evaporation of a spherically
symmetric charged black hole. We study the self-consistent one loop order
semiclassical back-reaction problem. To this end the mass-evaporation is
modeled by an expectation value of the stress-energy tensor of a neutral
massless scalar field, while the charge is not radiated away. We observe the
formation of an initially non extremal black hole which tends toward the
extremal black hole $M=Q$, emitting Hawking radiation. If also the discharge
due to the instability of vacuum to pair creation in strong electric fields
occurs, then the black hole discharges and evaporates simultaneously and decays
regularly until the scale where the semiclassical approximation breaks down. We
calculate the rates of the mass and the charge loss and estimate the life-time
of the decaying black holes.
