I don’t think a space heater would work, it’s AC, unless you have an inverter. Are there any other esk8ers with a board near you, you could try the battery on ?
Good call - I have a car inverter that might work - Thanks
That likely only runs off 12V
You’re just raining on my testing parade @scepterr - There are no electric skaters here besides maybe a couple of boosted boards…
I’m just trying to prevent fires ,
At this point… im secretly wishing this battery pack goes up in flames assuming that it doesn’t catch anything else on fire.
Any chance you’re in or around NYC?
What would be interesting to see would be how hot do they really get… though might be a bit hard unless u have someone with cat phone (infrared camera)… as im not sure how reliable would be to fit just a temp sensor in the battery compartment…
… on a side note, it somewhat looks like it could really be counterfeit cells… but im not sure is this the case, as it looks like they can offer decent punch but then during longer use get really terrible ?
Not saying your cells are not genuine… but it sure looks like tough nut to crack lol…
I suppose yeh, if you got infrared camera it might reveal some spots which are problematic… then it should be possible to see whenever the cells get hot or is it something else in the chain that drags the voltage down (gives huge resistance)
Yea might be worth looking at. I could ride the hell out of it and punish it, remove the cover as fast as possible then use my temp gun to see if i find any hot spots.
As far as counterfeit, they very well could be. I tried to find a reputable seller that had “good” reviews but that was one of the shaky areas of my build.
So where did you order your cells?
Well… u might try to do it with a temp gun but im not sure will you be able to compare the temperature in a decent way…
Though if you do find massive difference in temp between cells, then yeh, maybe you could find which cells heat up more (if there are such cells compared to the rest of the pack, though you said all of them measured just fine and none was out of place or so)
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As about riding conditions - as i understood from your first post - the cutouts/massive sag also happens on flats right? u mentioned something like every 15mins… or after 15mins during the ride…
Would be interesting to see whenever the gear change would improve the situation a lot, when do you think u will get the 40T gears for the wheels?
I ordered them from ebay - based my decision upon reviews - but still an iffy situation.
The massive sag happens all the time (now that I can see the live stats on the phone). After about 15min of riding, it will sag enough or I’ll usually hit a hill to take it into the 30v range to cause a shutoff (which is what seems to be happening) - In the screenshot above, where it goes into sub 30v is when i lost all acceleration. After searching the forums, I have found a decent amount of people with the same issue but never really found a solution (Search VESC cuts out on acceleration).
I have the 40T and waiting on some longer belts which are on the way but after going through all of this analysis, I’m not sure that is the issue at heart. I know that will give higher torque and will use less power starting out…But… Looking at the watts to amps to volts… the dropout shouldn’t be happening like it is.
yeh, ebay might not be the best place to order cells… thats for sure 
I havent really looked into cutouts but i think most could happen due to limit being reached and this should happen more for bms… not for vesc I think
Have u tried to really limit the current output… like 2x lower as it is now?
It sounds to me like you unfortunately bought counterfeit cells, especially considering the article posted earlier about all the fake HG2s
I actually have stopped discharging through the BMS and then added 100A 58V fuse… Then last night I removed the fuse to make sure there wasn’t anything going on there. That’s a good idea. I’ll set VESC at 5A each just to see what happens…but im not hopeful.
@jmasta : i wont argue with that statement as it is possible… however, I figured that some testing might be able to bring the issues to light… They hold charge… Low internal resistance etc.
5A might be too low. If cells are any decent 10A x 3 should be good. So 30A total, 15A per vesc or so. Cant see your original settings but i think.it was 60amp total, what is in theory max of what cells should output
Otherwise set at least 10A per vesc, 5A will be really lowish i think… u still want to ride it after all
yea original was 30Ax2 … At some point in this thread i cut it down to 25Ax2. I’ll chop it down to 10A for experimenting but ultimately will hope the Chi Boards battery is the end game.
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Just a quick update - Got 40/16 up and going now. Although the system is a little snappier, it still does extreme voltage drops when accelerating.
ChiBoards just sent out a new 10s3p - Will report back once I receive and get it installed.
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Received the new 10s3p battery from @barajabali (Chi Boards) today. This happened to the fix to all my problems. Even after extensive acceleration test, I could only get it to drop to 35.5v from 41v.
So that leaves me with the reasoning being faulty/counterfeit batteries or I damaged them somehow. Even after voltage and internal resitance test, they still checked out okay.
Thanks for the help and input everyone.
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Convert the “LG” cells into USB power banks, they’ll be good enough for that, get some use out of them You can get a housing with module that you can just pop 18650s into, they’re no more than $10.
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