A new model-independent parametrization is proposed for the hadronic form factors in the semi-leptonic Bbar -> D l nu decay. By a combined consideration of the recent experimental and lattice QCD data, we determine precisely the following Cabibbo-Kobayashi-Maskawa matrix element and the ratio: |V_{cb}| = 41.01(75) * 10^{-3} and R_D = 0.301(5). The coefficients in this parametrization, related to phase shifts by sumrule-like dispersion relations and hence called phase moments, encode important scattering information of the BD interactions which are rarely known so far. This formalism is also applicable for any other semileptonic processes induced by the weak b->c transition.