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How to read battery percentage?



I have two e-boards, both with zippy 6S batteies. Both boards have lipo battery indicators that convert the voltage into remaining capacity, but something I noticed is that both indicators don’t drain in a linear line. When the battery indicator gets to 50%, the reading starts to drop quicker. By the time it gets to 30%, it is only a matter of a couple minutes before it reaches 0%.
The indicators are different brands completely and they suffer the same issue.
Any thoughts on how to accurately read capacity remaining?


Those are accurate. The lower the voltage the faster it drops.


is there any smart battery indicators that counteract this to make a linear drop? Smartphones and other lithium powered devices decrease linearly.


Not that I know of.


I use HobbyKing’s HK-010 Power Analyzer - it measures cell voltage and percentage remaining. It also balances your cells, so that you can maintain healthy batteries. I’m not sure if this will help you? :slight_smile:


The phone’s battery indicator percentage might decrease linearly, but the battery voltage doesn’t, which your battery indicators are showing.

In the below picture is the discharge curve for a LG MJ1 Li-Ion 18650 cell.

The voltage is pretty linear in the 100% - 20% after which it will very quickly drop down. A better way to figure out how much battery life you have left based on your indicators is to charge the Li-Pos with a charger that can show how much capacity it has charged back.

Zippy batteries are Lithium chemistry.


So its basically a monitor and a bms? That would be awesome.


Not simultaneously, you can balance the cells when the battery isn’t in use/under load. It is an epic piece of kit, though :slight_smile: