Microcontrollers such as the Arduino Nano can be used for simple battery measurements and tests. With TestLab software on the PC, the controller can be conveniently managed. 

Small rechargeable batteries can be tested without much effort: An Arduino Nano can measure important parameters such as voltage, internal resistance, and capacity to determine the condition of the battery. With TestLab and the TLScript scripting language, presented in two other articles in this 2026 Circuit Special, the controller is managed for the measurement tasks. The software can be downloaded here.

Battery testing project

Button Cell

The small NiMH battery in button-cell form comes from a solar garden light that was completely destroyed by moisture ingress. The label reads 1.2 V 40 mAh. My experience is that such batteries can be reused even after prolonged deep discharge. Usually, the capacity decreases and the internal resistance increases. I wanted to know more about this. The battery is charged and discharged t...