The invention discloses reduced order battery thermal dynamics modeling for controls. A vehicle includes a traction battery that is comprised of a number of cells. A controller operates the traction battery according to a temperature for each of the cells. The temperature is based on a number of coefficients representing a contribution of at least one cell boundary thermal condition and a heat generated in the cell to a steady-state temperature at a predetermined location within the cell. The contributions may be filtered to predict a dynamic response of the temperature to changes in the boundary thermal conditions and the heat generated in the cell. The coefficients may be derived from a full-order model. The resulting reduced-order model requires less execution time while achieving accuracy similar to the full-order model. In addition, a range of characteristic temperatures may be obtained for each cell.