GPIO RPI4 manager for van battery stats

Prerequisites

Hardware:

• RPI4
• Breadboard and connectors
• Analog Voltage sensor (it is possible to build it by yourself creating a voltage divider with some resistors)
• Analog Current sensor (ACS758 o WCS1700)
• Analog potentiometer
• ADC converter (MCP3008)
• Some leds and resistors (optional)
• Some physical buttons (optional)

Software

• Pi OS (10 or later)
• MySQL server 8 installed (or docker compose)
• Python3
• NodeJS (12 or later)
• A Web Server where to post the stats data (in this case my own api server, you could comment this part if you want to work locally by directly querying the db)

Installation

Hardware

Sensors and ADC

Leds and buttons

Pictures

Software

• enable serial port interface via sudo rspi-config
• clone this repo in your rpi home dir git clone https://github.com/sacconazzo/gpio-rpi-van-battery-stats.git
• install dep. with yarn install and sudo pip install -r requirements.txt
• create mysql server and database (you can use docker-compose.yaml in /db folder)
• create table battery-snaps (you can create it running yarn db:prepare)
• configure .env file like .env.example
• configure a startup script in your RPI (example in /etc/rc.local) adding:

cd /home/pi/gpio-rpi-van-battery-stats
sleep 30
sudo yarn collect &
sudo yarn manager &

Outputs

Developed to provide updated data in 4 different stacks:

• Publish to external REST/HTTP
• Publish to MQTT
• Expose with a REST/HTTP
• Send with Socket.IO

Output managed example

Realtime data

{
    "dayWeek": [
        {
            "day": "2024-02-25",
            "bmV": 13.26,
            "bmVmin": 11.91,
            "bmVmax": 13.38,
            "b1V": 13.26,
            "b1Vmin": 11.9,
            "b1Vmax": 13.35,
            "b2V": 13.26,
            "b2Vmin": 11.9,
            "b2Vmax": 13.36,
            "b1Ah": 7.2,
            "b2Ah": 2.7,
            "temp": 24,
            "tempMin": 23,
            "tempMax": 35
        },
        {
            "day": "2024-02-26",
            "bmV": 10.55,
            "bmVmin": 10.01,
            "bmVmax": 13.43,
            "b1V": 10.55,
            "b1Vmin": 10.01,
            "b1Vmax": 13.44,
            "b2V": 10.55,
            "b2Vmin": 10.01,
            "b2Vmax": 13.44,
            "b1Ah": -1.2,
            "b2Ah": 29.8,
            "temp": 23,
            "tempMin": 20,
            "tempMax": 35
        },
        ...
    ],
    "realtime": [
        {
            "timestamp": "2024-02-27 12:07:57",
            "bmV": 12.65,
            "b1V": 12.08,
            "b2V": 12.08,
            "b1A": 0,
            "b2A": 0,
            "temp": 34
        },
        {
            "timestamp": "2024-02-27 12:07:47",
            "bmV": 12.35,
            "b1V": 12.3,
            "b2V": 12.64,
            "b1A": 0,
            "b2A": -1,
            "temp": 34
        },
        ...
    ]
}

https://api.giona.tech/domotica/battery

Realtime dashboard

https://app.giona.tech/#battery