  Growing demand for fast charging and optimised battery designs is fuelling
significant interest in electrochemical models of Li-ion batteries. However,
estimating parameter values for these models remains a major challenge. In this
paper, a structural identifiability analysis was applied to a pseudo-2D Li-ion
electrochemical battery model that can be considered as a linearised and
decoupled form of the benchmark Doyle-Fuller-Newman model. From an inspection
of the impedance function, it was shown that this model is uniquely
parametrised by 21 parameters, being combinations of the electrochemical
parameters like the conductivities and diffusion coefficients. The
well-posedness of the parameter estimation problem with these parameters was
then established. This result could lead to more realistic predictions about
the internal state of the battery by identifying the parameter set that can be
uniquely identified from the data.
