Awesome dooooood!
But calm down and be patient hahahaha you are right good in time with what you have built 
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OK - action videos galore! 
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Did you manage to get your battery working ?
Not yet. Battery works I just can’t charge it. Daughter wanted to try and ride it so I took some videos of that. I don’t have any 2 pin connectors so not sure what I’m going to do just yet.
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This is the clean way, but you can just use some bare wire really if you stay on low current
I’m not sure it’s an issue, but I forgot to put the small rubber insulator around my 5.52.1 charge port and the enclosure. I skinned the enclosure in aluminum carbon fiber. While I was making the battery two of the BMS wires touched the aluminum carbon fiber and short circuited. Confused me for a while as I couldn’t figure out what had burned / happened. Then I saw the two burnt BMS wires and realized the aluminum carbon fiber was conductive. So I think the outside of my 5.52.1 connector is probably touching the carbon fiber. Could this be the reason it won’t charge?
Thanks for your help. I wish I knew enough about electronics to trouble shoot this myself!
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That could be the reason why the cells discharged that much, and that could have killed/put in safe mode the bms
Did you unplugged everything from the bms then plugged again after that ?
Yeah be carefull with carbon fiber, it’s definitly conductive, you should capton/fishpaper everything
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I’m going to increase the charging port hole diameter and wrap the charge port in kapton tape. Hopefully eliminating any potential contact issues with the carbon fiber. I’ve got the insulator on the outside and heat shrink wrapped both terminals on the inside.
I’ve charged another 48 batteries (bought enough for 2 boards three months ago) to 4.20V give or take ± 0.02 using the LiitoKala charger and plan to rebuild the battery tomorrow with them.
I couldn’t find a way to jump two ports on the BMS to charge one 4 pack at a time within my soldering / connecting abilities. The space between pins is pretty tight and I figured I’d screw it up at some point and short something. Better safe than sorry I suppose.
Hopefully, when I get the battery re-built with balanced cell packs the BMS charges and works as planned! I’ll post results either way 
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So I rebuilt the battery and put in fully charged cells today. BMS listed everything at 4.17… 4.16… and I rode for an hour or so to where they now read 3.8 and some change. All within 0.05V of one another.
Still can’t get it to charge. I read a Voltage of 50.2 from battery positive to C-. And a Voltage of 46.2 from battery positive to B-. Should they be different?
I unplugged sensor wires, etc. Still get the same results. Charger indicates it’s fully charged and BMS says it’s charging but doesn’t seem like anything is happening?
See if you can get hold of another charger. The one you have might be wonky, so good to troubleshoot that if possible
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It says “temperature below charging temperature limit” and it reads “-30°”
I assume you don’t have the thermistors plugged, so i’d try deactivating the temperature protection in the configuration tab of the BMS.
Also, stupid question, but have you tryed hitting the “charging” button ? I had a smart BMS that wanted to be said to get to charge mode every single time
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I have a feeling I know what’s wrong…
Did you plug in the temp sensors into the BMS?
Your app shows they are both at -30°C. If the temp sensors are not connected, the BMS won’t turn on charging.
Connect them and it should work. There is a way around them if you don’t have them tho.
Go into settings and disable the temp sensors or change the limit for the temp sensors. Also turn on charging
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Haha at the same time
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I was faster than you on this one ^^
But the fact he gets to different voltage reading before and after the BMS ticks me, most of the time it means bad connection somewhere between the p-groups
@MarkVa1
When you do connect the BMS, try 1) connecting just the battery leeds without the balance leeds, and mesure the voltage after BMS
2)then plug the balance and mesure again
Edit: i’d try also mesuring the difference between the pgroups manually and not only relying on the bms readings
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I think it is because he had the charger plugged in while measuring. The 50,2V comes from the charger and the 46,2 is the actual battery voltage. They are different because the bms locked charging.
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Thanks guys! You’re the best! I didn’t realize the BMS came with temperature sensors and they were not plugged in. Plugged them in and it seems to be working quite well now. What a relief. I feel a bit stupid for not remembering the BMS came with two small black wires but that’s probably more of an organizational issue for me
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Added a stabilizing bar to the front trucks tonight. From riding around the pressure from the hex nuts / lock washers on the octagonal couplings isn’t enough to keep them from misaligning and skewing the front one side or the other after a few miles of riding. Hopefully this bar will help prevent the misalignment from occurring. On future builds I’ll probably put two bars opposite one another to provide more stability. But clearance around the bushing washers is an issue…
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Took it apart today and replaced the batteries with Molicel P26A and added some LED lights. The lights fit well, just needed to drill some holes in the aluminum base plate and run the wiring. Didn’t get to ride in complete darkness due to storms, but the Molicels make a huge difference with braking. Just a much better overall ride. Had the helmet on - might have even reached 25 mph 
… I can foresee a daredevil future… 
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I feel the industrial designer in me getting emotional when seeing works like this! Great work mate!
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Ya your garage setup is cool 
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