A charged black hole is a black hole that possesses electric charge. Since the electromagnetic repulsion in compressing an electrically charged mass is dramatically greater than the gravitational attraction (by about 40 orders of magnitude), it is not expected that black holes with a significant electric charge will be formed in nature.
A charged black hole is one of three possible types of black holes that could exist in Einstein’s theory of gravitation, general relativity. A black hole can be characterized by three (and only three) quantities:
- its mass M (it will be called a Schwarzschild black hole if it has no angular momentum and no electric charge),
- its angular momentum J (and called a Kerr black hole if it has no charge), and
- its electric charge Q (a charged black hole is called a Reissner–Nordström black hole if the angular momentum is zero or a Kerr–Newman black hole if it has both angular momentum and electric charge).
A special, mathematically oriented article describes the Reissner–Nordström metric for a charged, non-rotating black hole.
The solutions of Einstein’s field equation for the gravitational field of an electrically charged point mass (with zero angular momentum) in empty space was obtained in 1918 by Hans Reissner and Gunnar Nordström, not long after Karl Schwarzschild found the Schwarzschild metric as a solution for a point mass without electric charge and angular momentum.
Source: Wikipedia and http://www.trinhmanhdo.org