My first build dickyho 6x2 Samsung 40t

DIY Builds
#1

Long time lurker, finally decided to pull the trigger on a build. Been collecting parts for the last couple months. So far i have.
Skateshred 42"drop-down deck
Dickyho 6x2 drive kit
2 dickyho 6374 motors
Dual maytach ecu
Dickyho controller
eBay 120 amp bms,
For the battery I got 36 Samsung 40t for like 4 bucks a piece on sale. Gonna do a 12s3p. Started working on that first.

Decided I wanted to individually fuse each cell but I didn’t really have the means to test fuse wire so I decided on doing this.

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Also didn’t have a spot welder but I have a 1100 watt soldering station so I just went quick with it. Seemed to work well. Planning on putting ring terminals on the bare wires or maybe bullet connectors so I can remove each parallel group to fly as I travel for work alot.

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#2

People will give you shit for that battery but I’ll give it my not too sketch to not work certification :boom:.

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#3

That’s an interesting way of going about it. I understand the reasoning. Just seems a little overkill .

I hope you lurked the forum for awhile before creating an account.

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If you haven’t read through this thread yet start here

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#4

Haha it does look sketch. Im confident in it though.

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#5

I’ve been lurking on esk8 builders for like 2 years, here for a few months. Really only made an account recently to access marketplace.

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#6

Are you worried at all about blowing fuses and getting a cutoff at high speed? I suppose the VESC should go into low battery slowdown mode if one pgroup dies.

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#7

Phew. Ok good. Just making sure bud. Dont want to see you make a mistake that will result in catastrophe :bomb: :fire: :sparkler:

What about the solder joints on the fuse rubbing a hole in the shrink wrap and shorting .

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#8

If I blow a fuse only one cell will go, still 2 left per p group. However they are 40 amp fuses so really unless 1 cell fails I doubt it will blow.

There’s a few threads on cell level fusing that are pretty interesting. That’s where I got most of this info. However If a cell does go bad, the fuse will likely blow saving the rest of the pack.

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#9

Haven’t thought about the shrink wrap rubbing off, that’s a good thought.

I’ll make sure to insulate the solder joints with something before I shrink wrap them.

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#10

As @b264 always says, smack your board against concrete for 30 min, if nothing breaks you are good.

That doesn’t look like it will withstand too many smacks. Good luck.

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#11

It’s an interesting concept BUT there’s to many places for things to go wrong. The vibrations of a board should never be underestimated.

I think the soldering has to be very good and having good insulation for vibrations will help.

#12

If you tape all the p groupes well with kapton tape to avoid any connection comming loose then it could be possible to withstand the Brian test.
@Itsmedant you forgot the final test where you ride a 30km/h and try and kick a so called empty box and crash bit. If the board survives that then you are good :kissing_heart:

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#13

If you fused the negative side of the cell, then you wouldn’t have to worry about the fuse digging into the cell casing and causing a short. (Because the outside layer is negative)

Also, I see you’re using hot-glue for insulating those fuse connections.

If you’re pulling a lot of amps from the cells, then those fuses are bound to heat up a bit, and that could melt the glue away, making it pointless. (Or vibrations will simply kill it) Please use some normal heat shrink instead, and use kapton tape to stick the fuse flush to the cell.

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#14

There’s a post about individual cell level fusing and that’s not the way to go about it. You need a bus bar and solid core wire.

What you’re doing works, on the bench. But not only are you adding a TON of weigh with all that wire, you’re adding thickness and most importantly— tons of potential failure points. Lose a few fuses during a voltage spike or something in there and you’ve got no brakes if you dont get dumped.

That hot glue better be able to handle 80*

I’ll look for the link

Nevermind. First result
https://forum.esk8.news/t/cell-level-fusing-discussion/4548

You need to reference the amp charts. There’s not bench testing required

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#15

Yeah, that s first pack was more of a test than anything. I have tons of fish paper and kapton tape on order.

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#16

Yeah I agree with your reasoning here too. Theorhetically it should work but there are so many failure points that would make me question the viability of it

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