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Discussion Starter · #1 ·
Hi All
Trying to get my head around this...
For a system running a 40kw motor at 48V I think I will need an 800AH Battery Bank to run it for nearly an hour?
If I am using 2.3V 40amp LTO Batteries I will need 21 Cells in Parallel to make a 48V 40amp unit and I will need 20 units to make 800watts? For a total of 420 cells?

@1.2kg each, total weight = 504kg

@$30 each, total cost = $12600


Can I control it with a 100kw controller?

I haven't even started looking at Battery Chargers yet....
 

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Yes I was under the impression that low energy density pretty much eliminated use of LTO for most propulsion cases where weight matters?
 

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Discussion Starter · #3 ·
Yes I was under the impression that low energy density pretty much eliminated use of LTO for most propulsion cases where weight matters?
Thank You for replying John.
Weight is not an issue as it's actually for a monohull sailboat.

I was just wondering if I have my figures correct, I am trying to learn EV Systems and know nothing : )
 

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Even more so but OK.

40000W draw is max not real call it 30000W.

800Ah, call it 650Ah usable times 48 call it 31000 so yes an hour's runtime, hopefully at hull speed.

Even number's best so 22S gets you 50V nominal
20P gets 40Ah to 800Ah, so 440 cells.

Elcon will do a charger, max 2.85Vpc so 62V, but 2.7V probably better for longevity so 60V even.

As high a charge rate as you can afford, no problem, even at Tesla's highest possible kW rate from 3-phase if you have a private dock.

You'll be the pioneer so expect arrows. . .
 

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Don't even consider solar, wind or hydro, you'll only be using this for short maneuvers to well-powered docks.

Unless also carrying a big diesel genset.
 

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Discussion Starter · #8 ·
Yeah she's quite a bit bigger than that I'm afraid.
she's a 46' Delta, similar to a peterson. 40kw is still under powered for her, 30kw and I imagine I'd get in trouble....

I think the most I have gotten out of this is that battery power is not an option yet.. so I will feel a little less guilty burning dinosaur juice to get her in and out of port.

I do really appreciate your time.
 
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