Efficient state of health estimation of Li-ion battery under several ageing types for aeronautic applications

An accurate state of health (SOH) estimation for Li-ion batteries is essential to provide the electrical performance evolution over time and with operation for users. In this context, an efficient method based on Incremental Capacity Analysis (ICA) is proposed to estimate the SOH for Nickel Manganese Cobalt oxide (NMC)/Graphite battery. We focused on the qualitative and quantitative ICA according to different ageing types under aeronautic conditions: calendar ageing at 55 degrees C and - 20 degrees C, power cycling at 45 degrees C and 0 degrees C. Linear and logarithmic regressions are observed between SOH and dedicated parameters which are location and amplitude of peaks. According to these correlations, a partial charge based on cut-off voltage is investigated to estimate the SOH of unknown ageing state of NMC/Graphite batteries. Using our method, only 1% error is found between estimated and experimental SOH.