My project contains:
Currently I am powering it from a 10000mAh USB power bank. But in order to avoid brutal powerdown, I need a "smart" battery solution where the battery level and charging/discharging status could be monitored and user informed about it.
My current measurements show that at rest it consumes 220mA, max current is about 800mA, and normal use current is about 500mA.
I'd like it to be able to live from full charge something around 24h. During that time, it would be actively used for about 2h, while the rest of the time it would be in "resting" mode, consuming no more than 220mA. So, I figure I need 2*500+22*220=5840mAh (at 5V) battery solution.
I have checked for the necessary circuitry needed to monitor the battery charging (Sparkfun Battery Babysitter - LiPo Battery Manager) and a voltage regulator. But I am puzzled about the Li-Po element - for a 3.7V Li-Po output voltage, stepped-up to 5V that would mean I need 5840/3.7*5=7892mAh (if my calculation is correct).
So, do 8000mAh Li-Po elements exist? If they do, it seems they are extremely rare.