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:

1. 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.
2. Better high temperature performance.
3. Long life, 2,000 charge/discharge cycles
4. Large overcharge tolerance and safer performance
   
5. Simplified battery management system and battery charger