Aaaaaiii 28p 
I thought my builds were crazy
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seems legit. so this design?
I think I know what you mean - the shape of the bay plate would not be as stiff and would bend under the weight of the battery, given the lare distance to the “pivot points” of the trucks?
we’ll see 
if anything goes wrong, I can always screw it to the neck
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Yes and yes 
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This board will be crazy. I thought that you only did groupbuy for the cells and that first 12S28P photo was a joke
If you are not sure if the nickel strip will be able to distribute the current well, you could add cables like this. But probably won’t be necessary if you will always use 4wd.
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And I thought I’m predictable in jokes/sarcasm Well, every day brings something new
Had that idea as well, but I was not able to think it through with nice desing 
we’ll see how it’s gonna behave
Long time no see guys
I’ve spend the weekend welding the battery, tomorrow I should get 3dprinted parts for the deck/enclosure, and then we should be close to first ride.
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Dood 12s28p why… at this point just better to increase voltage than capacity and dear god have you increase the capacity, this is a car not a skateboard anymore 
If I compared that to my 50G 12s9p this should have like 320km of range compensating for that extra weight a bit, with only a 100 pit stops you could do a around the world tour with that board :).
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With a battery that big are you planning to just run it between like 80%-20% at all times? Could improve cell longevity and (IMO almost as importantly) stay within the much flatter part of the discharge curve. Much much less of a difference in performance between “full” and “empty”
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Have you considered adding an xt90 with full pack voltage available? Then you can plug your board into an inverter to power your house during a power outage.
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not sure if that will be the case, most pessimistic guess is 150km. but be sure I’ll find out how much I can get.
you brought me to an interesting idea - do you know that feeling when your battery is almost dead, but you need few more kilometers so you move your cutoffs a bit?
if I set cutoff start to 3.2/cell and cutoff end to 3.1/cell, drain the battery to that point, and still need a few more kilometers to get home, I’ll still have 1.5wh on each cell, about 500wh in the whole pack - that’s like 20 more kilometers I might be able to go full range of some boards
might try to tinker a bit with max/min voltage to keep the battery safe, but to still have the option to max out the range with slightly overcharging and slightly overdischarging it. I think it’s essential to know the capabilities
I’ve added single 14awg line to be for direct charging (bypassing flexibms) to allow me charge faster than 10A without balance. theoretically I could be able to charge with 140A, but I have the system not designed to handle that. the 14awg wire and 25x0.2 strip should handle 50A, and my fastest charger does 25A.
also, I’ll be able to bring TS100 sodering iron with me (with step-down) for longer trips, and plug it to this port.
regarding the inverter-power outage situation - I live in Prague for 4 years, and I’ve never had to deal with this
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You could also power a campsite or charge your buddies boards haha
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Well for me 15% is around 30km so around a full charge i get closer to a 100km before any noticeable drop off and then never pushed that long in a single charge but I would guess 120km if in one sitting, you should be way beyond 150km even 4wd, sure you take more amps because more motor, but also each motor has to do less work, biggest energy loss for you should just be raw weight, as 12s28 is just massive.
As to answer your question, I dont know, I have a soft cut off at around 30% and the board just gets sluggish but the batteries keep giving without issue, yet again you have such massive battery it should never be a concern.
it is
buttake in account I’M used to 150A on these motors sure I’ll make them suffer teribely
that is actually true, and imagine scenario where the conects exists, and how many kilometers you can still get on it. i’m really looking forward to testing this
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My first build was a 12s4p with 26650 LiFePo4 cells that could each do 50A continous and 120A burst, they were more than plenty to haul my ass to oblivion, I think the biggest issue you will have is just sheer weight of the board, as you + board + just everything else securing that battery will increase battery consumption.
Just a thought are those fatboy hangers 8mm or 10mm axels, honestly I could see them snapping or bending with this high amount of weight, you are really pushing these builds in a way I never imagined 
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the battery prob only weighs 20kg or so (1/5 of the weight of a human) it shouldnt be that much of an issue on the axles
I have seen people bending 8mm Axles with just their body weight, 23kg battery + 12 kg board itself is just 35kg, then you need to also consider the board being so heavy will make it really in the danger zone for so thin axles, hopefully the rider is somewhat light but say he’s a “hefty” 90kg like myself thats 125kg on those axles, wouldn’t take much at speed to bend something.
My fluxx build has 12mm Axles and has less than half the weight of this board.
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This build log has me feeling all sorts of ways…so exited/scared/concerned to see the finished product
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fair enough
my point is that if the axles are designed for a standard (reasonably large guy - 120kg+) they should be fine with this
maybe 10mm axles would be better
Holy god that is a big battery, excited to see how this all turns out!
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well, I started this before the finality trucks were available. imo they would be a better option. we’ll se how things go
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