def Vdiode(Icell, Vcell, Rs):
    """
    Calculate Vdiode from current, voltage and series resistance.

    :param Icell: cell current [A]
    :param Vcell: cell voltage [V]
    :param Rs: cell series resistance [:math:`\Omega`]
    :return: diode voltage [V]
    """
    return Vcell + Icell * Rs