No it is not going to work like that, you need to connect - in the very right of the top row to plus of the lower block straight through! Think it through.
Follow the current flow and you find the mistake.
The plus P row at the bottom is orphaned, you need to arrange the cells in a way you have all “digital” 8 shaped strips at the bottom, alway 6 cells connected.
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How’s that?(above) Thanks for catching that, it’s 4am and I was winging it.
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I’m late to the party, but for context, 12s4p eve 40PL, full BMS (220A/400A), and charger is going to cost me $660 Canadian (all in) from a local builder. (That’s about $485 USD). He builds many batteries for the locals, including for efoil. He says the 12s3p seems to be the sweet spot for those who have built backpack foil assists, so that’s probably a good call. And the 12s3p is nice for power and keeping esc heat down (from what I’ve read in the forum). Curious how the cooling will be in the backpack. Water splashes on the aluminum box for cooling? Maybe passive air cooling is fine for your esc?
Context: I’m also just starting my build and considered building the battery pack myself, but didn’t have the confidence to do the cells myself. Lots of stuff online about safety of the builds, but I’m lucky I found this builder. He knows his stuff for cells, connectors, thermals, etc. Sounds like you have no one local though, even on Oahu :(. I opted for 12s4p with 75200 pro v2 vesc with 6384 motor. I over spec’d for the vesc and the larger battery pack to hopefully have no heating issues because I plan to efoil a bunch at the start and then progress to foil assist (hopefully) for downwinders. Haven’t been to Kauai yet, but love Oahu and Maui
It depends on the prop - how much esc heats
Brand new to this forum and to foiling. I literally just found this diy foil assist this morning and am solidly down the rabbit hole. I have most of a setup in carts but am wondering if you were successful with the greenworks batteries? They are easy to get and I have 2 with chargers already. I would be super excited if they worked out. Thanks
To be honest, I haven’t made much progress in my foil drive assist contraption, just getting some interest back due to wintery lack of wind… But from previous projects, those batteries have been very dependable, and able to happily deliver 40A for long acceleration phases.
When pairing them, you need to make sure they’re both in the same condition. Ideally, both starting from new, and both getting charged and used at same time, to keep a similar number of cycles on each. If you don’t mind those constraints, or the lower power density, or the 10S / 36V voltage limitation, then they can work. A modern12S3P would easily outperform it on every front. Aside from price and modularity.