A method for predicting the loading capability of an accumulator by measuring
the
current I, voltage U and temperature T of the accumulator, and comparing the measured
values with the corresponding values of the response of an equivalent circuit diagram
of the accumulator, the parameters of the components of the equivalent circuit
diagram and the state variables are varied so that a match with the measured values
is obtain. The loading capability is deduced from the matched parameters and state
variables determined in this way. The equivalent circuit diagram has the form -Uo-R-CS-
and the input voltage U of the equivalent circuit diagram is a voltage
that is corrected with respect to the measured battery voltage U, the correction
function containing as variables only the current I, the voltage U and the temperature
T and as a nonlinear term a logarithmic dependency on I. By using the equivalent
circuit diagram, the instantaneous loading capability, i.e., the response of the
battery under a hypothetical load with an assumed current value I, is predicted
by imposing this current value I on the equivalent circuit diagram with the found
parameters and evaluating the voltage response calculated.
