Abstract: A system and method for determining an estimated battery cell state-of-charge and for determining an estimated battery cell resistance and for determining an estimated battery cell available energy is provided. The method includes measuring at least one of a battery cell voltage, a battery cell current, and a battery cell temperature. The method further includes determining an adapted estimated polarization voltage vector. The method further includes estimating the battery cell state-of-charge based on the adapted estimated polarization voltage vector and at least one of the battery cell voltage, the battery cell current, and the battery cell temperature. The method can further include computing the estimated battery cell resistance. The method further stores values corresponding to the estimated battery cell state-of-charge and the estimated battery cell resistance and the estimated battery cell available energy in a memory.