I honestly like li-ions better. Really, I would want to pull no more than 15 amps, and to do that, I need a 12s6p, which I just can’t fit onto my board and keep some amount of thin appearance.
@PXSS what numbers do you want?
Find out your max power draw and average power draw on the board you ride with LiPos. I’ll get you a configuration that won’t sag too bad.
How many cells can you fit? E: PM me or start another thread, I feel like we’re hijacking @Maxid’s thread lol
It’s cool. We solved my issue (at least so far) and are talking battery technology now - i am all for that. We should just make sure to make all the information public somehow instead of “hiding” it in here
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I started doing an excel calculator late last night that will hopefully solve the power requirement guessing. So far I can estimate the drag force from a standing human and the rolling resistance of our wheels on asphalt. I need some help from you guys to verify my numbers for rolling resistance, on a nonpowered board have someone tow you while each of you hold to different sides of a fish scale to measure the force required to tow, (I attached a rope to a door and pulled myself… i have no friends 
jk). Either way, if you can give me your total weight incl board and pull force, then I can fine tune the rollimg constant.
Now I need to figure out the mechanical torque equations… Does anyone have no load data? I need voltage, rpm, current, and power draw vs time. (I’d do it myself but I still haven’t finished my build)
Maybe this video helps. I was trying to make a constant ride with the cruise control at 25 km/h. But you can’t compare the voltage sag here with proper high discharge Li-Ion cells because i ride with Laptop Cells which are not made for that. But they do the job. But of course the voltage sag is really high with them.
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Have you ridden your board yet?? Was it fixed?
I tried but could not ride long due to cold temperatures. At -4°C it is not a lot of fun to ride - also to see those levels of discharge I would have to first use up quite some battery after charging it yesterday. I changed the cut offs though - will get back to you guys once I have some graphs again.
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And your battery performance is also greatly diminished at those temperatures.
I think that is no problem when you keep the board inside your house and go directly out for a ride. So they will be at room temperatur when you start and during the ride they get a little temperature by being used. You only shouldn’t let them cool down.
Here is also another video with the same round but this time with lots of accelerating and braking. When you compare the used Wh with the previous video then i used roughly 70 % more. It always looks so slow on the videos.
Video was made with my Android app so everybody can make his own video. Just check for my other thread if your interested.
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You were really only getting that kind of millage? That seems like something was wrong. I haven’t messed with my vesc setting much at all and got a pretty easy 15 miles on my 10s4p the other day, and I wasn’t being very conservative on accelerating or speed. However only two large hills in that time and no head wind. I do weigh 190lbs though and my board is about 45 lbs.
Yea, I live in a very hilly area. Most of my riding is either up or down a hill around 11% grade. And regen braking doesn’t replace all of the power needed to get me up the hill, just a bit. I run hubs though, which explain some of that lost range. Generally, hubs need a lot more power.
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Good info here.
I think hubs need more power to create torque but maybe hubs could be more efficient on continuous flats. Will see soon. Anyone near SF with a pulley set-up who wants to come out and compare this week?
Ok that makes a lot more sense! If hub motors were more effecient they would totally monopolize the market. It would be so nice to now have a separate motor, mounts, pulley/sprocket, belt/chain. Lots of weight, room, and build time saved. Potentially money too!
To me, it’s a trade off well worth it.
Hey,
I have serious voltage sag when going up medium hill and pretty much just stops on steeper inclines. Im running 10s4p 30Qs with Vesc and 6374 200KV motor.
I think it might be because Ive got conservative settings in my Vesc but I could be wrong. Here is a bit of a screen grab from the Metr app. Any ideas whats going on!?
When I pushed it up the same hill for 20 secs then jumped on and gave it power, it starting pulling really well… for about 15secs then starting bogging again.
These readings are from a 15min ride with some flat areas and down hill in parts too. The last 5 mins was a significant hill but I felt the bogging even on a slight incline.
Can you upload the whole log from the metr app?
Also post your VESC settings, we can’t point to what is causing the issue without those 
It looks like your ESC is might be overheating. 78A is pretty hot. I think the foldback starts at 80C so maybe not.
I don’t think you are having voltage sag issues since your battery is nore than capable of providing 60A continuous. Something else is wrong
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Lets move over to the other thread… I was already commenting on your settings there. Please try to keep your comments contained to a single thread for one problem unless nobody replies for a day or so