Battery Discharge Logger & Profiler

Overview

This repository contains the Python control software (read_data.py) developed for my BSc thesis. The tool automates the process of recording battery discharge curves by synchronizing voltage readings and current measurements. The set-up is simple: The Arduino is connected parallel to the battery, while the PPK2 is in series with the resistor.

Schematic

It integrates two hardware components:

1. Arduino: Acts as a voltmeter to read the battery's terminal voltage.
2. Nordic Power Profiler Kit II (PPK2): Measures from micro-ampere to ~1ampere level discharge current.

The script logs Time, Voltage (V), and Current (µA) to a CSV file until the battery reaches a defined cutoff voltage.

Hardware

To replicate this setup, you need:

• Nordic PPK2: Connected via USB (Data/Power).
• Arduino (Any model): Connected via USB. Must be running a sketch that prints voltage floats to Serial @ 115200 baud.
• Device Under Test (DUT): The battery being discharged.
• Ohmic Resistor: The resistor in which the battery voltage will drop.

Dependencies

This project relies on Python 3 and the following external libraries:

• pyserial: For communicating with the Arduino.
• ppk2-api: For controlling the Power Profiler Kit II.

Arduino Setup

The Arduino script and required libraries are already included in this repository.

Installation

pip install pyserial
git clone https://github.com/IRNAS/ppk2-api-python

Usefull Links

• https://www.arduino.cc/en/software/
• https://docs.nordicsemi.com/bundle/ug_ppk2/page/UG/ppk/PPK_user_guide_Intro.html
• https://pyserial.readthedocs.io/en/latest/pyserial.html
• https://github.com/IRNAS