  We numerically and analytically calculate the properties of the bipolaron in
an extended Hubbard Holstein model, which has a longer range electron-phonon
coupling like the Fr\" ohlich model. In the strong coupling regime, the
effective mass of the bipolaron in the extended model is much smaller than the
Holstein bipolaron mass. In contrast to the Holstein bipolaron, the bipolaron
in the extended model has a lower binding energy and remains bound with
substantial binding energy even in the large-U limit. In comparison with the
Holstein model where only a singlet bipolaron is bound, in the extended
Holstein model a triplet bipolaron can also form a bound state. We discuss the
possibility of phase separation in the case of finite electron doping.
