Series Connected Cell Monitoring System of Li-ion Battery with I2C and Cloud Interfacing

Battery Monitoring System is a crucial part of a Battery Management System (BMS). In commercial Electrical Vehicles (EV) battery packs and battery-powered devices, the two most important parameters are the State of Charge (SOC) and State of Health (SOH) of the battery. The EV has multiple cells connected in Series and parallel and makes the Battery Packs to drive the motor. So, the battery real-time Status monitoring is a preliminary part of the SOC estimation and Cell Balancing algorithm. Battery monitoring System helps to detect the current status of the battery’s cell pack and makes alert of any unpredicted situation and avoid damages. This paper proposed series-connected Lithium-ion battery real-time monitoring with the help of the Internet of Things (IoT) with state-of-charge estimation methods for Battery cells pack. Also, the individual cell status will be updated in the internet cloud and onboard the HMI (Human to Machine interface) LCD Display. With the help of the Battery Open circuit voltage (OCV), the initial SOC is predicted and finally implemented with the Coulomb counting method using the current integral. The total pack voltage of the Battery and the charging-discharging currents were measured by the LEM LA-55p current sensor and LV-25p Voltage sensor respectively. The ESP8266 system on-chip wi-fi microcontroller is used for cloud computing and the data is displayed using Blynk IoT cloud.