The invention provides a battery
state prediction method and
system. The method comprises steps of: establishing a random
data assimilation function model I*t = f(U, I, T) representing a function relationship between the dischargeable time t of a battery and
voltage U, current I, and temperature T; computing the complete
discharge curve Ik*t = f(U, Ik, Tk) and the dischargeable time tk:tk= f(Uk, Ik, Tk) / Ik of the battery to be tested on a current operating condition by using the random
data assimilation function model I*t = f(U, I, T) and according to the
voltage Uk, the current Ik, and the temperature Tk, measured in real time, of the battery to be tested; and predicting the SoC value and the SoH value of the battery to be tested according to the complete
discharge curve and the dischargeable time of the battery to be tested on the current operating condition. The battery
state prediction method and
system may perform assimilation treatment on battery parameters on different operating conditions, adapt to operating conditions with continuously changed
discharge current and ambient temperature, may accurately predict the
state of health and the
state of charge of the battery, and is good in instantaneity, high in accuracy, and easy to implement.