At 44.7 is when I start accelerating. At 46 I am still braking.
So that would be 5.9V sag then.
evil sorcery and lies.
i wrote 2% but i meant about 2 volts. it depends on the terrain of course. But i’m also not drawing anywhere near the packs actual capacity. a 5P can deliver 75amps continuous on paper and a little more in reality but i’m only drawing 55 in settings.
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Is this a single motor build? You’ve seen mine and sayekim sags compared. I really doubt 2V, but maybe.
how the cool kids say it…
METR OR DIDN’T HAPPEN
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Or as Hulk would say it.
55 puny amps 
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Try it. Reduce your max allowed power draw from your massive battery and see if the sag reduces.
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Oh, I know it will.
I also know that your way ends up with a board with1% less performance and 100% more reliability.
But I am a stubborn stupid fuck sometimes even though I know better.
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its a crazy world i live in. One foot in the DIY realm of turn everything up until it burns then take pictures of the flames, and one foot in the realm of production where shit has to work every time or i get emails and shipping charges and wasted hours fixing shit.
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I sag wayyyy to much
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I may have found a reason for my battery troubles, I noticed my range was down, and sag was up, I figured the cheapo batteries were just getting ready for the bin, but today I received an over voltage fault, searching tells me that’s a broken battery pack nickel strip possibly. Tomorrow I’ll open it up and examine
Well it took 4 years, and 8 builds to get to this point. And working with a lot of talented people in the industry. I’ve spent at least 1/3 of my day on average over the past 4 years building and testing my boards and motors. Just motors alone; I used to spend months at 8 hours a day building and testing the hummie hubs with hummie. But as with anything, you always are left wanting more power lol.
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Guys you should test the Samsung 30Ts, they sag the least amongst favorite cells for esk8 a 4P is enough to draw 140A of maximum current discharge, they can also take high currents for regen/brakes and charge much faster using high current chargers without getting warm.
Some people prefer the 40Ts because of the increased range but I rather have a really torquey and agile board with 25% less range than a average board with average maximum discharge rates.
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I really would like to see a real esk8 life comparison. All the data sheet stuff is nice and good, but our average amp draw never gets close to what they tested and compared.
It will never be the same with different boards and rider, but non the less it would be great if we would have a test line up and people could drive that routine while logging the battery voltage.
Something
flat land 10km average 30km/h urethane
flat land 10km average 30km/h pneumatics
Hill climb 10x 100m at XY degree urethane
Hill climb 10x 100m at XY degree urethane
Etc etc.
I think from a data base like this we would get way better information than on a static discharge test at xA
Nothing will compare to real life testing, I followed the data sheets and trusted the cell brand reputation and the board feels way, I mean WAY, faster even at low current than any of my 30Q variations
What kind of amp draw are you experiencing? What’s the settings?
Maybe @pookybear as well since he’s my local guru.
anybody
Hey everyone, just wanted to see if my battery is working properly. 10s4P 30Q
My remote goes down a rough 20 to 25 % on the battery indicator during WOT.
Now THe Feather remote has weird way of calculating that # so to not read into it too much here’s the Metr Data (just got it and already so clutch)
as data points i submit the time stamp around t =20:18
38V @ 2A,
and then
35V at 47 A
~ 3V worst case therefore.
gearing is tall. I want to say 18:47 on bergs? I honestly forgot the pully size.
Is this indicative of battery issues at all? its my first pack and its already had surgery once 
This was the first ride after that surgery. DIscharge only BMS I had one pack that was lower by ~.3 v. and show voltage fluctuations upon touching the welded areas through the fishpaper/kapton tape.
Disconnected the P group, disassembled the group and verified all the capacities. Chalked it up to a bad weld, though i did not find anything distinctly wrong. rebuilt everything, went for a ride and here we are.
That’s a nice graph. Just wonder how the state of charge does influence the voltage sag. Could imagine that the sag is different at 4.2V than at 3.3V with the same load 
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I took these few days points from all over, from full charge to the end of some rides, and overall it seems to be fairly linear from the looks of it.
I think a voltage sag metric would be a cool addition to metr.
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Yah change in voltage from totally full to totally empty is only a 1.2V difference per cell in series so I wouldn’t suspect the charge level has a huge effect on the sag, that said at lower voltage some sag is likely to put you down under the safe discharge voltage so want lower discharge at lower voltage but luckily the vesc soft and hard cut offs seem to basically handle this if set properly.
Just looked through some of my logs looks like about 2V of dip at about 20A draw for a 10S5P LG HG1 cells I think. My lipo based one is more like .5V to 1V drop with around the same current draw.
Take numbers with grain of salt. No lies but I’m a small dude around 115lbs and on flat ground so my current draw is relatively low. Pneumatics are still about half efficiency compared with urethane build too despite the light load.
Oh also the voltage sag I’m pretty sure is directly related to the internal resistance of a cell and so shouldn’t change much over a single discharge but may change as the battery wears over time and has more cycles.
Just came here to say that upon my recent observation of the exteme decline in acceleration performance, that my Lipo packs now sag a delightful ±5V. I think it is time to save up for a new set lol