This is my stance on the BMS debate 
use it to charge and discharge.
On the set up for now
Will sell the pcb, nickel tabs and enclosure
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Does this mean each 12S3P pack is modular, that I can combine each module with the other even though they might have different cycle life?
e.g. Building a 12S6P out of two kits, then adding another 12S3P kit (to make 12S9P) some months down the line (each having their own BMS).
Why not just make a charger / circuit that limits the recharge to 95% of capacity?
I know from a friend that when fully charged his brakes on his kaly doesn’t work really well, it cuts and freeroll at around 3/4 of the braking distance.
Charging the battery at 95% will also help increase its lifespan, so it might be beneficial both ways.
Back on the discharge BMS, I am also using a discharge BMS, haven’t had any issues yet, and everything seems to work fine. But all the comments are a bit worrying.
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Sure you already know about it, but have you looked into the rheostatic brakes from Maytech?
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My man thanks
I did not know about this
Will get in contact with them ASAP
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Mixing old and new battery packs causes headaches, is ok if the user is willing to manage and monitor the packs.
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Not available for 12s. I would run one if a 12s one exists.
I could care less about the cells, if I could run -100 brake without the esc blowing up and having 0 brakes I would.
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Maytech told me some months ago now that they had a 12s version. Definitely worth getting in touch @Kaly
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Oh shoot, no idea. Need to send them an email i guess, thx for letting me know!
Isn’t it technically just an antispark switch that turns on at a set voltage and dumps to a resistor? Or is it more than that? Any idea?
Oh. Just looked at specs. Maytech claims it can dissipate 5A max. That’s more like overhead protection, not take-over system
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I think it’s more as an emergency thing at full charge, not meant to be abused 
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Damn. I wish there was a system where massive braking currents can be set and have the energy be dumped into a huge copper bus bar or something. Would be especially beneficial for decks with small batteries without sacrificing braking power.
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I have one of the maytech rheo brakes in one of my boards. Charged it to 100% and went to a downhill area with lots of places to bail just in case. Brakes worked fine but I imagine they’d get real hot under continued load.
It’s meant to be wired in parallel with the battery so it will stupidly take whatever amp regen you throw at it until it melts. I wonder if you would feel any change when you hit full charge in the middle of riding and brake energy goes fully to the rbrake 
should just be smooth from the esc standpoint and the bms just cuts recharge.
In the end, I took it out for space reasons and the fact that I never immediately downhill after unplugging my board.
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I’ll get a few units to give it a try and report back
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@Kaly I bought these and in need of some tips. Didn’t realise when I bought, but they’re slightly different from the kit in this thread.
PM me if you didn’t want to cause confusion in this thread, also need some more info on the BMS’.
I have 4 PCB’s and 4 BMS’, does that mean I essentially have enough kits to build 12S12P?
Are there recommended upgrades I should do to the kit before putting it together? Like the broad Nickel strips over the back?
@sesat
Just awaiting on new batch of PCB
But with the corona virus the factory have been delayed.
@malJohann
That kit is for the first generation
A bit different than the one on this post.
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Realised that, hence the ask for tips. Are the BMS’ the same? If you have the time, please PM me some deets.
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bump @kaly it’s my birthday on wednesday let me celebrate by sending you a bunch of money! battery pcb kits, powder coated enclosure tubs, maybe you can find cosmetically damaged deck with gaz pedals and prototype hubs? take my money! you know i’m in it for the long haul!!
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This is what caught my eye. What kind of plastic cover is that? How do you seal it to the aluminum? I assume it’s for light waterproofing.
Edit: after taking apart my board, the double-sided foam tape is what seals the film to the enclosure.
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