Fix it
gonna start this off with a chat about chargers, BMS and cells being somehow highly damaged in a short period of time.
I will start pulling up sources and info, with all the pics I can find.
oh one issue being the SB fb group post that has lots of people talking about packing being ruined from charging overnight was deleted even though the comments were full of people talking about how you should never leave it plugged in past green. so yeah.
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Just a side note…having even some kind of “top of the line” BMS means nothing if it isn”t set up properly or a “dumb” charger (a power supply) that never turns off is used.
The BMS can watch for overvoltage, overcurrent, and overtemperature and never do a thing for a charger that sits there holding the pack at its full charging voltage continuously.
Some BMS’ can detect the drop in charge current when a pack is full and shut off the current, disconnecting the charger, but it has to be capable of doing that and be set up properly.
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dangit I really should have screencaps the deleted post about battery packs not lasting a full use after being left on charger.
Charlie here has a SBX battery melt down and nearly burn his house down.
remote sitting in storage gets burnt somehow…
the battery came loose and shorted the power switch maybe?
Could that be corrosion and deposits from leaking (salty) electrolyte from the battery?
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If the charge system dose not terminate the charge when the current drops below a threasholed (float charge) I could believe it to happen.
If there charger and bms dose not terminate the charge then thay charger goes agains all manufacture instructions for charging cells that I have seen
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I’d say some sort of short happened and over heated the battry. Age or environmental effects resulting a deterioration of insulators could have created a short in storage. Or just a leak the chemicals inside li_pos are parity nasty
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Quinn from the fb group sent me here. Bought a board 2nd hand. They said remote was hard to turn on. I got it to turn on and connect a few times but it seems to turn itself off. Pretty sure my remote’s power switch is broken. it doesn’t “click” like the brown switch. and it is deformed. hoping to get a part number or recommendation on a replacement. I googled pcb switch types and it seems to be a tactile switch, but I’m not sure what size to look for for. I don’t have any calipers to get specific measurements at that size. I can solder well enough that I feel like I could remove and replace it without much issue with a replacement part.
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hmm glad you made it and were able to post pics! alright hopefully someone knows the switch type and can help
Close enough possibly
CNET review.
I said it was not great to not review any of the maintenance aspects and only the riding experience.
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motorized things are not so easy to diagnose things on the go.
those zz bearings seem to fail quite a bit.
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@Battery_Mooch I found the screenshot my friend took when Aaron was talking about how awesome the battery for the sbx should be.
Talking about what VESC based esc to buy for a v2 esc swap.
then lots of reports of batteries not functioning and needing to be sent in with no report of what is the problem being solved.
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LOL…the bq78350 chip is only a part of what makes up a BMS. This chip monitors the current going in and out (tracking that) and has some health reporting and logging features. But it doesn’t balance or directly control any of the BMS protection features.
It is designed to work with one of three other monitoring/balancing/protection chips, the bq76920/76930/76940, to create a 3S-15S BMS depending on which of the other chips is used.
The bq78350 is a good chip, as are all of the Texas Instruments (TI) chips, but it cannot create a BMS on its own and it’s not the “best” unless it’s exactly what you want for a particular application. I guess it has what he was looking for. 
He might be pairing it up with a microprocessor and his own BMS software, or perhaps one of the other TI chips it pairs with (though I would think he would have mentioned use of a full TI chipset), to create the BMS.
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This is, every picture of the inside of a sbx battery ever posted on fb
![118585750_3323992624331662_9034941395426557013_n|375x500]
(upload://qhG9cOLzka6haNCWi3PJTGnv3hd.jpeg)
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Wow, so much going on inside that board…vibration-sensitive connections, crush damage, all kinds of fun things.
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Could I ask a favor? At your convenience, could you post a picture of the mating connector for this? It’s the main battery connector to the rest of the board?
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