Is anyone still interested in this?
Iām honestly in talks of having the DieBieBms made at a factory and it will make all sparkswitches obsolete.
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It doesnāt matter where the board is made, the design is the key element here. This one also would make everything obsolete. This has microprocessor so I can do like hold to turn on/off battery level on led blinking speed and etc. Plus this board disconnects positive wire not negative like all others.
P.S. It would also had a aluminium case to cool down those mosfets, and etc.
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Jtag has opensourced this bms and it can be made as low as 60$ in the right quantity wich is the price of a decent bms and sparkswitch,
I can create a sparkswitch with just two pieces of wire 
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Yes, but current wise itās the same as other spark switches, just two MOSFETs without any heatsinks so no more than 40A could be pulled continuously.
Well heās working on that MoreAmpsSheild that apparently handles 240A, and does a bunch of other neat stuff youād probably want if you were running that much current.
Still, get the feeling some people would still like to forgo the complexity of a BMS. So a good switch, is still a good idea.
No matter the quantity itās impossible to go that low. Seriously have a look at the BOM.
On his more amps shield I do not saw any more mosfets to handle more current so I donāt know how he is going to get more current from that PCBā¦
Plus my switch uses the same logic as his board for switching power, its kind the best solution you can get. Just I use more powerful mosfets and mcu 
It would seem that there arenāt more transistors on the board, but rather more parallel/lower resistance shunts so they can measure currents up to 240 A, without melting their current shunt resistors. Or so I would understand from his quoted sentence and the linked pictures in the reply.
I also have to wonder with @Kug3lis how they plan to keep their transistors from escaping into the atmosphere at such high currents.
Thatās why I am really curious how they handle the current, because current does not divide equally between paths so I am bit scepticalā¦
Plus the IRFS7530 has some high heat output at that currentā¦
250A through 0.0014 Ohm dissipates 87.5W of power, P = I^2 * R. 87.5W x 313 K/W gives a junction rise above ambient of 27387 K, or 3500Cā¦ 
(can be really wrong calculation as I donāt remember correct formulas) and itās only for single mosfet.
Where? and in what quantity? That deal sounds like a shenzen bait and switch to me.
Thatās what i was thinking. Maybe under $100 is possibleā¦ somewhereā¦
why is it rated for a 100amp fuse then? I run twin IRFS7730 mosfets at well over 50 amps all the time and theyāre fine. They seem to start having issues right around 60 amps under 200+ pound loads and the speeds associated with those amps, which for my weight class is above 40mph. Are 7530s that much different?
The load of skateboard is not continues, as I am saying for continues load max 40A, but for longboard 50-60A should be enough but not 250A as he states in his messageā¦
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On my board I will just put several SOT227B style mosfets on big ass aluminium plate and will not have any problem even with 200A 
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Also, Iād like to give you some constructive input on your anti-spark switch design.
You really lose the pro of using more powerful MOSFETs if you use them in the fully blocking setup, because you actually end with more dissipated power overall compared to the 2 parallel IRFS7530s in one direction. Your overall Rds(on) will be higher due to the current having to run through 2 silicon dies in series (even in the parallel version). Now if you plan on making a heatsink for it, then you might make up for the increased heat production by being able to pull the heat away more effectively due to more surface area to move the heat off of the packages to the heatsink, but overall wouldnāt it still run hotter, at least power dissipation wise?
IMO, MCU seems a bit overkill. I (personal opinion) believe that most people would want their e-switch to be as simple as possible. AKA itās either on or off. They want to disconnect their battery from their motor controller by holding a switch down for a couple of seconds and connect it back by doing the same again. I doubt they want to start faffing about with firmware and flashing it to the MCU. How are they supposed to flash the firmware again? are you going put a header to the board, which they can use? How many people have the programmers and the know-how needed to do this? Are you going to flash every board yourself you plan to sell? I really donāt think the MCU is the best choice in this case, but rather more simple logic gate based one, whichās output is toggled by holding down a momentary pushbutton.
Just my two cents.
I use them in the fully blocking way just to prevent burning the battery with a current running in from VESC or etc then the board is off. Either way, its how normal BMS looks, this whole switch is just a part of professional grade BMS just the switching part, the same design is in jtag version of BMS too. The MCU will be one time programmed because I saw saying that vibrations can make button switch and turn off the board while riding if anyone wants it can be a simple toggle switch. You will not need to program it or do anything related to it.
On the other note about fully blocking mode is like to prevent inbound current to battery then the battery is fully charged, or etc. It would work partially as BMS without balancing. Turn off the load then minimum voltage is reached or etc.
Yeah I just opened and saw he is using two different paths. My bad but if you look in other reference design of bms and etc you will see
