MEB Dirty Dervish | 12S Stealth Battery | Twin ESC | Hub Motor

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12S 5.2Ah is just 225Wh (double boosted and they hit about 5miles under normal conditions). from my experience i always need 10Wh/kilometer minimum (last record run exactly 9Wh/km!!!), usually more like 13Wh/km under normal riding conditions (with single motor) … so with your battery thats max 20km range for all my builds under “cruise” conditions and more like 15km range under my “normal” conditions (heavy carving at 30kph+).

you might have found the holy grail of hubmotor+esc combos or had really helpful wind/slopes. :stuck_out_tongue:

advertising at 260Wh is not correct in my books - you multiply the nominal voltage with the capacity, not full loaded cell voltage. thats because on avg, a cell will have its nominal voltage, so its 12x 3.6V x 5.2Ah = 225Wh

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I agree. The cells usually drop from 4.2v to 3.6 shortly after you start riding.

@whitepony Mmm thanks for the tip. I’ll change the calculation. I’m sorry about that, I always thought it was calculated at Full Charge. BTW, I love all your builds man! They all look Perfect :ok_hand:

@Pantologist 20mph cruising is pretty quick for cruising around specially if there’s people around. But yeah 20+mph is fine on the streets!

Have you noticed any voltage sag?

@Michaelinvegas Sorry about the late reply, I’m not getting notifications for this post and I’m not seeing it on the forum unless I search for it… It’s kinda weird. (Just found this topic got switches to muted on my profile and I didn’t realize) But anyway, I’m not really getting voltage sags on this battery. It’s kinda crazy because I’m so used to it for Lipos I’m expecting this to just do a hard cut off when I accelerate to hard but it just slowly goes into the cut off.

Just Updating with new Hubs! Same 12S Battery and Twin Motor ESC. Urethane Came off last hubs, waiting on screws to come in to test again.

#Super Smooth Standstill Start up!

Smooth Riding Also!

Had to cut my ride short grub screw came loose and started twisting around truck :confused:

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did you file a flat spot on the axle for the grub screw? I filed 2 flat spots (one on each side) for the grub screws and then i used loctite to hold them in.

hopefully you didn’t break a phase wire like I did on mine

@oriol360 What’s ur eta on the battieries I may give it a shot

@lowGuido I was nervous about grinding a flat spot on the actual axle, so I just tightened everything very tight! worked great for the one on the right but the left one not so much! Now That I know you have a flat spot I’ll go ahead and file a little spot for it. And yes loctite it all! And motor is still working perfectly!

@Michaelinvegas ETA on batteries are late July early August, So far first batch (which I ordered few extras also) looks on track to be shipping before August!

When I get my hubs I’m going to tap some treads right into the truck

@Bender That axle is tough!

Ahh I thought it was the thick part of the truck not the axle I guess a flat spot and lock-tite is the way to go

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Ha! I read this in Fry’s voice in my head.

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hey @oriol360 what brand of cells are you using in your production run?

They are a Chinese brand called Cham. They’ve been great for the 500 miles of stress testing I’ve been doing.

How many recharge cycles are they supposed to get? You’ve done about 40 cycles?

They’re rated for 1000+ cycles! I have around 34-36 cycles on this one. I’ve been testing for a month charging/discharging every day and some days twice a day! Going up and down parking garages as I do not have any hills in Miami :confused: and going full throttle with hubs. I have yet to go full throttle with a satellite motors as I have 250kv geared pretty low and it’s over 40mph which I’m too scared to hit.

So these are jacobs hubs ?

I’m sure most liion 18650s can do 1000+ but their capacity drops below 50%. Hopefully you can get to around 300 cycles and then test the battery capacity.

Pretty awesome using cells that are uncommon on esk8. Where did you buy them?