Agreed.
Many people don’t use a BMS too but that would never make it a good idea IMO. 
I would suspect that they are using a significantly more reliable BMS than any of us would though and use cells of known grade and condition, lowering the risks of cell failure.
Excellent.
IMO we can’t apply anyone’s individual testing to all cells. There are too many variables. I agree that LFP cells are a lot less susceptible to runaway, and the reactions a lot less violent, than other cell chemistries but it is still a pretty big risk to seal off a cell’s venting disk. This can significantly increase the pressure the cell bursts at and also force side wall ruptures which can raise the odds that other cells could be forced into thermal runaway.
We definitely all can choose what level of risk to take but I’m always worried about when we say that it’s okay to do because some related thing someone else did hasn’t blown up yet.
Potting does make for one hell of a durable pack though!
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oh yeah I meant like for the garage, not in the enclosure. Sorry didn’t specify
How would I figure a discharge rate for the lipos so they don’t exceed that while charging and riding it without problems
So lipo manufacturers specify the charge and discharge capabilities as a C rate, where 1C for a 2Ah pack is 2A. Your pack claims a 30C discharge on a 4.5Ah pack, so theoretically that would be 135A but that’s nonsense. They usually make continuous and peak discharge claims, but even the continuous ones are not reliable.
I’ll let one of the others give a better guideline for what the real number, but I’ve heard ~1/3 of the stated manufacturer number. That’s still 45A, pretty damn good for a cheap pack, but I’m not very confident in that number. Go through that thread Mutant linked way above, there’s some good resources on voltage sag (basically how much the pack struggles to keep up with high current draw), and I think some on other bits like how much heat gets generated or how much heat is ok. Even if it’s not all in that, it’s a good starting point
Would I find that In the description of the lipos
yeah it’s right in the title! Your screenshot above says 4500mAh 18.5V 5S 30C
Also here’s a diagram of the lipo I’m using, I’ll be using two so it’ll be double the amount
so using two doesn’t double every parameter, this is where you kind of need to know some basics of electronics. Gimme two secs and I’ll add some info
Here is another photo of my older setup (2 x 5s). You can clearly see how its done. this is not a bluetooth bms but same principle.
2 x series will give you 10s 4500mah at 30c.
30c x 4.5 / 3 = 45 amps continous.
Why divide by 3? because all lipo manufacturers lie so dividing by 3 is a good conservative estimate. You can charge these lipos 22.5amps n theory but thats way too much. charge at 1c which is 4.5a so they will go from 0-100 in about an hour.
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Did you add that wire that’s connected to the two lipos and the wires you were explaining to me earlier that gets connected to the cable that’s connected to the lipos?
That’s just with charging or it’s completely different when driving power to the VESC and motor?
Yes, I highlighted in green. the lipo balance plug goes into the extension, which then wires into the harness that comes with the bms. Disconnect everything and the lipos look like how they come from the factory.
What do you mean? The power from the battery will be 45 amps and you can charge the battery at 4.5 amps.
The wires that’s on the lipos that’s connected to the green, was it that way or you had to add them on
Lipos come with balance wires. I added the wire/extension highlighted in green and connected them to the wires going into the bms.
Ok, when you have the chance could you take different angled pictures so I can see it more easily and follow it
I appreciate the help a lot 
and for stopping me from buying a shit battery from meepo
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