  We systematically examine the properties of an electrically charged black
hole in Eddington-inspired Born-Infeld gravity with not only the positive but
also the negative coupling constant in the theory. As a result, we numerically
find that the black hole solution exists even with the negative coupling
constant, where the electric charge of black hole can be larger than the black
hole mass. We also clarify the parameter space where the black hole solution
exists. On the other hand, to examine the particle motion around such black
hole, we derive the geodesic equation. The behavior of the effective potential
for the radial particle motion is almost the same as that in general
relativity, but the radius of the innermost stable circular orbit and the
angular momentum giving the innermost stable circular orbit can be changed,
depending on the coupling constant. In particular, we find that the radius of
innermost stable circular orbit with the specific value of the coupling
constant can be smaller than that for the extreme case in general relativity.
Such a particle can release the gravitational binding energy more than the
prediction in general relativity, which could be important from the
observational point of view.
