Real time monitoring state-of-charge battery using internal resistance measurements for remote applications

Currently, the use of batteries as energy storage applications in various fields initiates many researchers to maximize the battery performance. One of the most important things to prevent a battery from over-charging or discharging issue is an accurate State-of-Charge (SoC) estimation of the battery. In this paper, real time monitoring SoC battery for the remote applications is proposed by calculating the battery's internal resistance when charging or discharging. When charging process, the battery's internal resistance (r_ic ) is low and will increase according with increasing the level of SoC. While at the discharging process, the battery's internal resistance (r_ids ) is low and will increase in proportional to the decreasing of the SoC level. The calculation of r_ids and r_ich are conducted by measuring open circuit voltage, load voltage, load current, and charging current using a voltage divider mechanism on the Arduino Uno and current sensors, respectively. LORA RA-02 SX 1278 433 MHz is used to transmit the battery parameters from the remote area (transmitter) to the server (receiver). Then the SoC will be estimated based on internal resistance calculation using these parameters on the server. With a simple structure, the proposed systems can be applied to the future remote real time monitoring battery systems.