  The Borel summation technique of infrared renormalons is applied to the
lattice determination of heavy quark mass. With Borel summation a physical
heavy quark pole mass and binding energy of a heavy-light meson can be defined
in a rigorous and calculable manner. A notable feature of the Borel summation,
compared to the usual perturbative cancellation of IR renormalons, is an
automatic scale separation. The two approaches of handling renormalon
divergence are compared in the B-meson as well as in an (imaginary) heavy-light
meson with a mass much larger than the inverse of the lattice spacing.
