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Li-Ion battery measurement system

Hardware and software for voltage, current, capacity and temperature measurements of Li-Ion battery.

The aim of this work was to realize a circuit that will measure voltage, discharge current, temperature and capacity of the Li-ion batteries, display them on the LCD screen and with software serial connections, using another microcontroller, on a remote computer. In order for the circuit to work independently, it was necessary to provide power to the Arduino Nano microcontroller with battery using a voltage regulator, to provide the required voltage of 5 V. In case the battery is discharged, we provide it with a charger for Li-ion batteries with protection to ensure that the battery will not be overcharged, and with that we have ensured the safety of the assembly itself. For voltage measurement, we used voltage divider with two resistors with a value of 10 kΩ. The Hall sensor is used to measure the current that through the consumer, the DC motor. The LM35 sensor is a temperature sensor that we use to measure the temperature of the battery. Capacity was measured by multiplying the constant current passing through the consumer by the time during which that current flows, and we measure time with the millis() function. In the end everything was placed and soldered on PCB board.

Additionaly, I tried some Serial connection with the other computer so the datas from Arduino Nano was sent with Arduino Mega to the second computer on Serial Monitor.”

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