In this project, we will build an IoT based Battery Monitoring System using ESP8266 where you can monitor the battery charging/discharging status along with Battery Voltage & Percentage. As we know, the battery is the most important component for any device as it powers the entire system. So, it is important to monitor. You will need the following components for the IoT Based Battery Monitoring System Project. You can purchase all the components online from. A lithium-ion battery or Li-ion battery is a type of rechargeable battery. Lithium-ion batteries are commonly used for portable electronics and electric vehicles. In this battery, lithium ions move. In order to Monitor the Battery Data on ThingSpeak Server, you first need to Setup the Thingspeak. To set up the ThingSpeak Server, visit. We will design a system to monitor this battery voltage along with charging and discharging status. For the microcontroller, we use WeMos D1 Mini which has an ESP8266 wifi-enabled.