The state of energy(SoE) operation region of energy storage lithium battery module was studied in order to improve the control precision and ensure the efficient and stable operation of the battery energy storage system. Base on the analysis of the simulated operating condition of tracking power generation schedule and wind-PV power stabilization

as well as the evaluation indicators

such as range and coefficient of standard deviation of battery voltage

the evaluation method of the SoE operation region for the energy storage lithium battery module was put forward. The actual energy storage lithium battery module was tested in the simulation experiment of tracking power generation schedule and wind-PV power stabilization. The SOE operation range of the lithium battery module under the two operating conditions was determined by analyzing the variation of the battery voltage range and the standard deviation coefficient of the battery voltage. The result show that the SoE operation region of the energy storage lithium battery module can be confirmed effectively according to the range and coefficient of standard deviation of battery voltage in the simulated operation experiment. It provides technical means for the energy utilization improvement of energy storage unit

and it has guiding significance to ensure the lithium BESS running efficiency and stability.