Build a custom solar weather station using a LiFePO₄ battery
Solar Weather Station Project
To build a safe, autonomous weather station, the choice of battery chemistry is crucial. That’s why the Lithium Iron Phosphate (LiFePO₄) batteries are the recommended choice.
- Safety: Extremely stable, no thermal runaway risk.
- Longevity: 2,000–5,000 cycles (vs. 500–1,000 for standard Li-ion).
- Temperature tolerance: Works well from -20°C to +60°C.
- Low maintenance: Ideal for long-term, low-power applications.
- Eco-friendly: No cobalt, easier to recycle.
- Solar compatibility: Handles frequent partial charging/discharging.
However, there are two main issues:
- The voltage range 2,5 to 3,65 vdc.
- The charging chip, Not widely adopted at the moment.
The prototyping phase
- Battery 32700 LiFePo4 (7200mAh or less)
- SolarPanel 5 Volts (400mA or more)
- Adafruit ESP32-S3 Feather - 4MB Flash, 2MB PSRAM
- BQ25185 USB / DC / Solar Charger with 3.3V (hack require to change the type of battery)
- Internal Temperature (BME280)
- Humidity (BME280)
- Barometric Pressure (BME280)
- Wind Speed ( Sparkfun Weather Meter )
- Wind Direction ( Sparkfun Weather Meter )
We need to put all the electronics and the battery inside a Stevenson screen (3D printed)
A Stevenson screen, or instrument shelter, is a shelter or an enclosure used to protect meteorological instruments against precipitation
The UI to visualize data
The next step will be to create a custom PCB, here is the project repository :
