Diagnostic of batteries based on microcontroller and smartphone

Abstract

This paper presents an approach to diagnose batteries with the help of microcontroller and smartphone. It aims to determine the available capacity, the state of charge (SoC) and the state of health (SoH) of a battery. A battery is aged by charging and discharging cycles, this process degrades the chemical composition of the battery. Thus, this paper aims at using two-pulse test to determine Ampere hour capacity (AHC), SoC and SoH of a valve regulated lead acid (VRLA). These parameters are related to the voltage drop after each pulse of current discharge. By using a microcontroller and smartphone, it is possible to easily change the controller parameters according to different size of battery. The microcontroller will be used to control current discharge based on two-pulse method and a discrete PID. A smartphone with an application based on Android program and via Bluetooth communication allows to change the parameters for the controller and monitor the performance of battery test. This concept is validated by simulations and experiments on an emulated system for availability reasons. This work takes place in a larger process which aims at providing local solutions for local problems according to the “Jugaad” philosophy, which can be seen as “frugal innovation”. The main idea is to re-use “old” elements such as automotive batteries in this case, to propose cheap and local solutions for off-grid village electrification.