Before reading any further - I’m not suggesting anyone runs their battery to beyond a safe limit and read any of the below at your own risk etc. etc. I’m aware cells are probably going to last longer if they’re not run flat each time - however for those unaware of the voltage thresholds on the Maytech controller (V3), this may be useful.
Something I’ve been experimenting with on my DIY Foil Assist setup with a Maytech controller is getting as much battery run time out of my small 10S3P pack when the battery is getting low.
Maytech are conservative when they estimate Battery % on the controller. The remote shows 0% when the cell voltage hits 3.2V (I asked Maytech this directly).
This means when you see 0% on the remote the RX is reading 3.2V per cell. Which is conservative. Many cells are rated to 2.5V minimum (such as the Samsing 50S cell). Here is a random capacity curve for the 50S (unsure how accurate this is - but the best I could find). I’ve assumed 20A which is more than what I use (I’m more like 15A per cell), and the capacity left between 3.2V and 2.5V is significant.
Maytech don’t want add a voltage reading as an option so as a work around I have been changing the settings in the remote to be 1 cell less (or 2 ) than what I use in the menu.
In my case with a 10S battery, I set the remote to 9S. Read the Maytech manual if you don’t know how to change this.
This means Maytech remote shows 0% (9S) at 28.8V (9 x 3.2V), which for a 10S battery means 2.88V per cell, still well within limits of the cell.
I’ve tested this 0% and I’m still well within the cell limit (and my esc cutout which is set at 2.6V was never triggered) - next I will be trying 8S setting (this should mean 25.6V at 0%, or 2.56V per cell).
Anyway for those who were ending a session when the remote hit 0% (or 10% etc.), just understand that Maytech have already put quite a lot of margin in this. Don’t get yourself stranded with a flat battery - but if you are like me and like to get the most out of a battery with this method you get a much clearer picture of how much battery you have left right at the low end of the battery when you want to know. The downside to this is for the first half of the session, the remote will read 100% battery, but I’m not bothered by this as who needs to know how much battery they have left when it’s above half full !