The battery builders club

Me too, ok 25A I don’t need :sweat_smile: but 1.5A balance current isn’t bad either :man_shrugging:

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You know, the FMA chargers, if you use their wiring and not JST-XH, can charge through the balance wires. I think this would be ideal, CC/CV for each group. They call it nodal charging, and the rate slow of course. 3A max.

Verses the common method: charge groups to slightly overfull and drain them down slowly until equalized.

Even if it’s slower overall.

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Trying to figure out a more compact solution instead of the parallel XT90, which is incredibly chunky.
Any issue doing something like 5.5mm bullets on the ESC side and AS150 on the battery side?
Besides being non-polarized and potentially very fuckupable :sweat_smile:
Don’t want to do XT60.

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PC building and esk8 building have so much in common.

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Maybe just solder them together?

On another note, I hope you are aware that the bullets are exposed here

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This is temporary for bench testing obviously. All bullets will be double heatshrunk.

That wouldn’t be a connector solution though.

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You could use this with screw and nut fixed.

Still not a plug and play option, but need less space and removable.

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Some bullet connectors

The latter 3 are all stubby, shorter than the usual 5.5mm. I don’t know if you’d save any space over XT90s though.

Here’s a pretty good list of amass stuff

http://shop.smc-powers.com/index.php?route=product/manufacturer/info&manufacturer_id=13&limit=50

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In example it is used for the baja relay.

It’s one of those, but it was from somewhere else, before they sold them directly.

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Much success. 12s8p 30qs got me over 40km with 20% left. 9inch tyres, mostly paved but going hard. That was off the first charge, I am hoping the second charge gets a bit more…

Had some minor remote issues which saw me eat shit but hopefully will sort that today.

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@Trampa i’m slightly confused about the 100a fuse…

The board has 2x60a motors,so Ideally I would want my max battery amps at 120 for maximum power.

Is the 100a fuse now a bottleneck? Or can I run 120 battery amps safely

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100A is the constant current the fuse can handle.
The fuses trampa use should be similar to this ones in the data sheet

You could run 200A for 10sec before the 100A fuse would blow.

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So theoretically if I was balls to the wall full duty cycle for like a minute at 120a, there’s a good chance I could blow the fuse… seems like a small fuse for a high powered board

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Theoretically. Practically you would probably need a big steep hill to reach that current for so long.
I run 125-150A fuses on mine without issues so far. But we also do not have steep hills around here. Max 120A for some seconds is what I could get out of mine @80A per esc.

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These fuses are slow and usually you do see lower battery amps than motor amps.
In practice we never blew up a fuse so far. Even the steepest road in the world is no issue.

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This is the reason to buy branded fuses vs random ebay fuses. Specs and accountability.

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While everyone else is busy building dickasauruses, I’m finally getting back to this flight friendly battery I started a while ago

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Now this is when it gets tricky the minimum curent the can handle safly a 100amp.

The chart is only on a avrage fuse so yours could be bettor or worse depending on all sorts of things but it’s a good middle ground

fuse only needs to blow at 1.5 times the curent so in theary a good fuse should blow between 100-150 amps. At full load all day long so at 120amps some will blow others will never blow.

The chart show it should handle
160A ish for 1000 seconds (16 minuits)
200A ish for 5 seconds
325A ish 0.4seconds

Id be surprised if you could blow it at 120amp in overload but there’s always a small chance. In a nut shell I wouldent worry about it as I would exspect every thing els to over heat and throttle down befor you hit the fuses limit (battery’s over heating VESC over heating cables over heating. This is no guarantee because you’re exceeding the manufacturers limits so there is a chance it could blow

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:ok_hand: cheers bro. I think it’s very unlikely that it will ever see a sustained 120a output, but the dude is 110kg at least and likes to push limits :sweat_smile:

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