🌡️ Minimalistic E-Paper Weather Station

🌈 A beautiful, eco-friendly weather station powered by E-Paper display! 🌱

⚠️ IMPORTANT: Please read the [Notes & Warnings] section carefully before proceeding with this project. It contains crucial safety information about battery configuration, charging, and sensor placement.

🌟 Smart • Efficient • Eco-Friendly 🌟

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🛠️ Hardware Components

🎯 Tested On	• Seeed Studio XIAO ESP32 C3 • Seeed Studio XIAO ESP32 C6
📟 Display	Waveshare 4.2inch TriColor 400x300 E-paper (15s refresh)
🌡️ Sensors	• TMP117 (Temperature) • BH1750 (Light sensing) • DS3231 (Time keeping) • BMP680 (Humidity & pressure)
🔋 Power	LFP 2x4000mAh (8000mAh total) Lithium Iron Phosphate Battery (IFR26700)
🔌 Other	2xBMS, capacitors, resistors, connectors, etc.

📱 Key Features & Updates

🆕 Latest Version v0.2.0-beta 🚀 Power Efficiency improvements

🎯 Coming Soon 📱 Web browser integration 🌐 Enhanced weather data 🎨 New display layouts

⭐ Core Features

🌡️ Medical-grade Temperature	💧 Humidity & Pressure	🔋 Smart Battery	🌍 Weather Data
±0.1°C Precision	Real-time Monitoring	Intelligent Power Mgmt	Global Forecasting
TMP117 Sensor	BME680 Sensor	2000+ Cycles	OpenWeatherMap

🎮 Smart Features

• 🌙 Moon Phase & Day/Night Tracking
• 🔄 Auto WiFi Configuration
• ⏰ Power-efficient Sleep Modes
• 📊 Environmental Monitoring

📊 Battery Performance

📝 Note: Historical data below is from testing with Li-ion ICR batteries. The shorter duration in cycles 2 and 3 (49 and 48 days vs 73 days) was due to incomplete charging (batteries not reaching full 4.2V). New performance data with 8000mAh LFP batteries (which are more cost-effective) is being collected.

ICR Battery Data

Cycle	Duration	Details
First Cycle	73 Days	06/05/2024 - 17/07/2024 (2 months 12 days)
Second Cycle	49 Days	~7 weeks
Third Cycle	48 Days	~7 weeks

LFP Battery Data (Ongoing)

Cycle	Full Charge Date	Battery Dead Date	Duration
First Cycle	January 09, 2025	Coming Soon	Ongoing

📉 Battery Life Trend (ICR Battery Data)

First: ████████████████████ 73 days
Second: █████████████ 49 days
Third: █████████████ 48 days

Current Consumption

⚠️ Note: Precise current consumption measurements for the entire project are not available due to equipment limitations. Please refer to the Battery Performance section above for real-world usage data and longevity estimates.

📸 Gallery

🌱 Eco-Friendly Features

• 📱 E-Paper Display (no backlight needed)
• 🔋 LiFePO4 Batteries (Lithium Iron Phosphate)
  • ✅ Cobalt-free chemistry, reducing environmental impact
  • ✅ 2-3x longer lifespan than traditional Li-ion
  • ✅ Non-toxic and more stable chemistry
  • ✅ Better recyclability due to simpler composition
• 📦 Recycled cardboard construction
• 💡 Smart light sensor for power saving

💫 Technical Specifications

🧠 Core System

Core Components

• 💻 XIAO ESP32 C6 (Recommended)
  • 32-bit RISC-V single-core CPU up to 160MHz
  • 320KB SRAM, 4MB Flash
  • WiFi 6 & Bluetooth 5.0
  • Ultra-low power consumption: ~15µA in deep sleep
  • 11 Digital/Analog pins
  • USB-C interface

Power Consumption Comparison

• ⚡ Deep Sleep Current:
  • XIAO ESP32 C6: ~15µA (Recommended for this project)
  • XIAO ESP32 C3: Higher deep sleep current
  • XIAO ESP32 S3: Potentially lower deep sleep current (untested)
    • Not used due to project's modest performance needs
    • Could be viable alternative for maximum battery life

📡 Sensors & Connectivity

Sensors

• 🌡️ TMP117 High-Precision Temperature Sensor

  • ±0.1°C (max) from -20°C to +50°C
  • 16-bit resolution (0.0078°C)
  • Low power: 3.5µA in shutdown mode
  • Temperature range: -55°C to +150°C

• 💨 Bosch BME680 Environmental Sensor

  • Humidity: ±3% accuracy
  • Pressure: ±0.6 hPa absolute accuracy
  • Gas sensor for air quality
  • Temperature range: -40°C to +85°C

• 💡 BH1750 Light Sensor

  • 1 - 65535 lux range
  • 16-bit resolution
  • Spectral responsivity close to human eye
  • Low power: 120µA active mode

• ⏰ DS3231 RTC Module

  • Accuracy: ±2ppm (±0.432 sec/day)
  • Temperature compensated crystal
  • Battery backup support
  • -40°C to +85°C operating range

⚡ Power System

Power & Display

• 🔋 IFR26700 LiFePO4 Battery

  • Nominal voltage: 3.2V
  • Capacity: 4000mAh (8000mAh total with 2 cells)
  • Cycle life: >2000 cycles
  • Size: 26mm × 70mm
  • Max discharge current: 8A
  • Operating temperature: -20°C to +60°C
  • Self-discharge rate: <3% monthly

• ⚡ TP5000 Charging Module

  • Input voltage: 4.5-8V
  • Charging current: 1000mA (adjustable)
  • Charging accuracy: ±1.5%
  • LiFePO4 mode: 3.6V cutoff
  • Over-voltage protection
  • Temperature protection
  • Short circuit protection

• 📟 Waveshare 4.2" E-Paper Display

  • Resolution: 400×300 pixels
  • Three colors: Black, White, Red
  • Active area: 84.8mm × 63.6mm
  • Refresh time: 15 seconds
  • Viewing angle: >170°
  • Operating voltage: 3.3V
  • Ultra-low power consumption
  • No backlight needed
  • SPI interface

🔧 Setup & Configuration

Initial Setup

1. 📱 Power on the device
2. 🔄 Connect to WCLOCK-WIFI-MANAGER WiFi network
3. 🌐 Navigate to the IP address shown on the display
4. ⚙️ Enter your WiFi credentials
5. 🎉 Device will restart and connect to your network

API Configuration

• 🔑 OpenWeatherMap API key required
• 🌍 Custom API support for personal weather station
• 📍 Configurable location (latitude/longitude)

Debug Mode

• 🐛 Enable via DEBUG_PIN (D6)
• 📊 Shows network diagnostics
• 🔍 Displays detailed error messages

Power Management

• 🔋 Battery voltage monitoring
• ⚡ Configurable sleep intervals (default: 15 mins)
• 🌙 Night mode with reduced updates
• 📉 Low battery failsafe mode

Display Modes

1. Normal Mode
   • Full weather data
   • Temperature, humidity, pressure
   • Moon phase and weather icons
   • Sunrise/sunset times
2. Limited Mode (Low Battery)
   • Basic temperature display
   • Battery status
   • Time and date
3. Night Mode
   • Display sleeps when dark
   • 5-minute wake intervals
   • Power saving features

🌿 Environmental Impact

🔋 Power Efficiency 📱 No backlight needed 💤 Smart sleep modes ⚡ Low power sensors 🔆 Ambient light detection

♻️ Sustainability 🌱 Eco-friendly batteries 📦 Recycled materials 🔄 Long lifecycle 🌍 Low carbon footprint

⚠️ Important Notes & Warnings

🔄 DS3231 Battery Safety ⚡

Most DS3231 modules are sold with CR2032 or similar cells which are not rechargeable. If you are using a non-rechargeable cell then **REMOVE** either the resistor or the diode marked in the above image.

🔌 TP5000 Charging Configuration ⚡

**IMPORTANT**: There are some misinformation over internet regarding the charging mode of TP5000. If you are using LiFePO4 cells with TP5000 then **DO NOT** short the above marked area with caption F.

Battery Configuration Safety

• 🔋 Parallel Cell Configuration: While this project uses two LiFePO4 cells in parallel, this is generally not recommended with TP5000 or similar charging circuits
  • Currently safe due to verified cell balance
  • Long-term balance cannot be guaranteed
  • Only implemented due to ultra-low current draw

Power Management Considerations

• ⚡ Current Draw: This project's extremely low current consumption (well below rated cell capacity) makes the parallel configuration safer
• 🛡️ Protection: Always use proper BMS protection for your cells
• 📝 BMS Setup: Due to limited 1S LiFePO4 BMS availability:
  • Using 4.2V BMS for 2.5V cutoff protection (Low Discharge Cutoff)
  • TP5000 connected directly to cells for proper 3.6V charging
  • This is a temporary solution until better 1S LFP BMS options become available

USB Charging Safety

• ⚡ USB Connection Warning: Disconnect battery when connecting USB to ESP32C6
  • XIAO modules are designed for LiPo/Li-ion batteries (4.2V charging)
  • Not compatible with LFP battery charging (3.6V required)
  • Dedicated USB-C module recommended
  • Connect USB-C module output to TP5000 input
  • Detailed schematics will be provided later
  • Simple setup despite complex explanation

Voltage Compatibility

• ✅ Operating Range:
  • All components work perfectly with LFP's lower voltage
  • Tested operational down to 2.8V
  • No impact on battery life or performance
  • LFP cells maintain stable 3.2V for extended periods
  • 6+ months of testing
  • Components designed for wide voltage range operation

Enclosure Design

• 💨 Ventilation Requirements:
  • Proper air vents are crucial
  • Ensures accurate sensor readings
  • Prevents heat buildup
  • Essential for environmental monitoring
• 🔧 Sensor Orientation:
  • TMP117 and BME680 must be mounted horizontally
  • Sensors should face downward
  • Prevents dust and particle accumulation
  • Ensures accurate long-term readings

⚠️ Please consider these points carefully before replicating this setup. Battery safety is crucial!

🤝 Contributing

📝 License & Credits

📜 License GNU General Public License v3.0 ✅ Freedom to use commercially ✅ Freedom to modify ✅ Freedom to distribute ❗ Must be open source ❗ Must preserve copyright ❗ Must use same license

👏 Credits 🎨 Weather icons by SeBassTian23 📚 GxEPD2 Library 💻 Community Contributors

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Made with 💖 and ♻️ materials