This project uses 2.4G BLE or WiFi beacon frame to broadcast sensor data, try to achieve:
1. Low power, able to run on indoor low light solar and super capacitor
2. Low cost, node cost as low as $3
3. Easy to develop
Today I started testing LiFePO4 battery. I had the idea of using LiFePO4 battery for few months. Now I just received the shipment early this week.
Few benefits use LiFePO4 battery:
Can use LiFePO4 battery directly power MCU, without LDO or buck converter. LiFePO4 battery discharge at 3.2V. This is huge for ultra-low power applications that average 3-15 uA. Even the really good LDO still consume 2-5 uA when MCU is sleep.
Better high temperature performance.
Long life, 2,000 charge/discharge cycles
Large overcharge tolerance and safer performance
Simplified battery management system and battery charger