Nope
It is not for sale yet
Will put it up by next week.
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Very well stated, @Kaly you have to understand its a lot cheaper to buy a new back that you damaged from voltage lows than it is to lose your breaks and get hit by a bus. We bypass the BMS unless its got the fets to do more amps than you need. I like the creativity though, youre really close.
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@Kaly if using this setup in for example a 12s9p and one module was to fail, would the system continue to run as a 12s6p?
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Fucking work of art!
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Yes, it will continue to work.
The main fuses on each pack will disconnect that pack if something comes up.
Loosing a pack will be noticeable by the loss of range and a loss of performance.
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How interesting. This is a scenario where I can definitely see an advantage to using a discharge bms… awesome work dude.
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But I see this causing a cascade effect
Let’s say that the battery is almost full and you are going down a hill, due to some minor variations one the packs detect and over voltage and shutdowns, now you battery is made of only two packs and has a higher combined internal resistance, so for the same braking current the voltage will rise more, and the other two packs will also shut down and you end up with no brakes and probably a blown ESC
I have to agree that not doing bypass is not good, maybe if you say that the BMS has custom settings and a way higher than 4.2 V per cell over voltage setting
Within the first 2 miles this can actually happen and it has to be taken as a known issue by the operator, after this 2 miles the packs can handle pretty big regen current while braking.
The main issue with bypassing the BMS, at least in the USA, is that if there is an incident with the battery your insurance company can denied you coverage base on this bypass, this is a big gamble to take.
With regards to this Regen current I’m working on a system to handle that by transforming it into heat.
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I got lost through all this comments, so are you guy saying bypassing a BMS is a good thing or not?
Another question for kaly, would you sell the whole set in the future? Battery mounted on the PCB+enclosure.
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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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