Modeling and online parameter identification of Li-Polymer battery cells for SOC estimation

Abstract

Finding an accurate and easily to implement model of batteries is an essential step in properly estimating the state of charge (SOC) of the battery in real-time. In this paper, an equivalent circuit based battery model with nonlinear relationship between the open circuit voltage (V OC) and the SOC is projected into several piece-wise linear functions. Moving window Least Squares (LS) parameter identification technique is then utilized to estimate and update the parameters of the battery model in each sampling time. The continuously updated parameters are fed to a linear observer to estimate the SOC of the battery. The effectiveness of the proposed modeling and estimation approach are verified experimentally on Lithium Polymer batteries. © 2012 IEEE

Sensitivity analysis of lithium-ion battery model to battery parameters

“…In our previous publications on online adaptive parameters identification and SOC estimation of different lithium ion batteries [11][12][13], using a Thevenin-based model we showed that the model parameters change under different conditions of SOC, C-rate, temperature and ageing. We also illustrated that ignoring the changes in the parameters with offline identification causes transient and steady-state errors in SOC estimation results.…”

“…(11) . (12) In order to better analyze the system, the steady state value of the change in the response of the system to changes in the parameter α can be calculated by equation 13:…”

Modelling of unmanned aerial vehicle – tricopter

“…In scientific papers there are many elaborations about Li-poly cells, not only including chemical processes [5,7], but also simplified models, which represents battery voltage from state of charge [3,13,17,18]. Author decided to choose simplified model without temperature compensations due to good cooling provided by airflow.…”

Influence of Battery Parametric Uncertainties on the State-of-Charge Estimation of Lithium Titanate Oxide-Based Batteries

“…Electrochemical models are conventional models that use the equations governing the electrochemical phenomena (chemical reactions) that occur in a battery cell [25,26]. The implementation of these models requires extended knowledge about the battery chemical, mechanical and electrical properties and thus they are more appropriate for battery design optimization process than for battery SOC estimation.…”