This beautiful ride belongs to @Aubcar! I spent the last few weeks building this out and came out really nice. Lots of inspiration from the enterprise build.
Parts list:
Subsonic Century with eboosted enclosure
12S5P 21700b cells in flexible configuration.
Focbox Unity running Vesc FW 5.1 with smart reverse. 12 awg motor phase wires, XT 90, METR unity module. MR60 motor phase wires.
Avio Mk2 herringbone gear drives on Kahua trucks. Otang purple bushings
Blue bergs
Hoyt Puck
Here’s some photos of the original parts:
The 12S5P came to me built but the owner elected to have me rebuild it. It’s done with 0.2 x10 nickel and series connections are 5x or more. Flex connections are 2x 14awg. This deck was made in their stiffest configuration and still has quite a bit of flex, even with the enclosure installed. The pack can flex in two places to account for this.
The previous configuration was the following. This is what it takes to fit 12S5P into one of these enclosures. It’s very possible, the BMS will just sit above the focbox or VESC.
This arrangement required a long wire to be run from B10 to B11 down the length of the pack. Didn’t love that.
I was already planning to make the new pack flexible, but I also decided to change the configuration of the P groups. This required 5 total folded series connections, compared to 1 on the prior. It was a lot of extra work but the result came out great. Folded connections are reinforced with double fishpaper rings on the positive terminals and a strip of adhesive paper across them which makes the fishpaper layer flush with the top of the positive terminal. This virtually eliminates the possibility of those connections getting near the can of the positive cell, which is the only place they can short their. On the inside of the connection is fishpaper, kapton and 3m double sided tape. This keeps the distance between cells consistent, reducing vibrations on the folded connections. I’m not a fan of folded connections if you can’t tell
.Here’s the new layout. If you see this and are already wondering, yes it made BMS wiring a PITA too
Now the B10 to B11 connection is short. And B11 will be fixed to B10 with glue and fiberglass tape.
Some build photos:
Here’s the new B10 to B11 connection. B10 has a 0.2 mmx10 strip across the P group. Then a second layer joins each half in the center and goes to B11.
The staggered B11 and B12 groups have x2 14awg connections that are continuous pieces of wire, stripped at the connection site but not cut. Nickel is folded 0.2 x25 for 50mm of connection total width. There were a lot of carefully hand cut shapes to provide the right connections without having them cross over each other. The flex connections in the center are 0.2 x75mm width.
Here’s some more build pics. I’ll be logging onto the PC in a bit and can add some more info.
18 miles on it already. Rides beautifully and I’ve had it clear to 35mph without loss of stability. Absolutely great board.
Motor 60/-50
Batt 35/-10
Vesc FW 5.1 and Hoyt have had no hiccups
Back to add more later
And finally, what we all wanted to see.
I’m glad to see that I can cram 12S5P in my board if I decide to upgrade cells!