Can someone give me a basic 101 overview of LiPo battery percentages and how to interpret (or point me to a resource)? We got our Octoquad flying and I’m doing multiple series of tests to learn about predictable power consumption and flight times possible on a single charge. Here’s what I think I know about LiPo:

- Nominal, resting voltage of a LiPo cell is 3.7
- Max, full charge of a LiPo cell is 4.2
- Storage voltage is +/- 3.8
- Minimum discharge voltage (don’t go lower or you could damage battery) is 3.0-3.3
- I understand we use voltage vice capacity to assess how charged a battery is because of difficulty in measuring capacity.

For discussion purposes, I’m using a Tenergy LiPo 5-in-1 tester on Tattu 30,000 6s batteries.

Here’s what I need help understanding:

What does the percentage rating mean ~ specifically, what constitutes 0%?

Presumably, if a tester says your 6s battery is 98-100% charged and voltage is 25.2 then 100% = 25.2 volts. But clearly 0% is NOT 0 volts since a ‘dead’ battery is not necessarily a fully discharged battery. Is 0% represented as the minimum required 3.0-3.3 per cell or 18-19.8 volts?

If yes, then the 0-100% charge range is measuring how much of the 5.4 volts is available for use (25.2 – 19.8)? That appears to be the case. At 39%, volt total measured was 22.88 which is +/- 39% in the ball park. Battery is smart enough to know how much of total voltage is available for use and testers calculate that as percentage.

Thank you for corrections or validation.

JB