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Best battery for electric windlass

Like Mike says. For one thing, even though LFP is capable of high C discharges, it doesn't mean it likes it.
For the other, you shouldn't be using your windlass without your engine running anyway for safety reasons.
So a shallow-cycle starter battery is best. It's basically what they're made for. They're also a lot cheaper, so hey ;·)

Also, putting batteries in the bow... I wouldn't do it. They'll get banged around a lot, and I'm quite sure they won't like the sharp stops of the vertical motions - not would anything they're laid on. Just use thick enough wire.

[EDIT] Also, most LFP have a BMS. In this case, not a good idea. Cheaper to replace a battery than repair a boat :·)
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Erm... starter batteries are not made to run a high load for 3-4 minutes solid. They are made for the 15-20 second start load. You really want more of a dual purpose starter/deep cycle for this in lead acid land.

My windlass spec's in at 1200 watts, at 12v that's 100A, at 14v, more like 85A.
With lifepo4 I do not suggest building say a 100ah battery to run a windlass. I'm looking at more like 280ah for this. The surge of the motor stall is right around 1c, and running load is around .3c. Those are well within the lifepo4 capabilities.

Great point on bow positioning, in my case I have a nice little space that mid-ship but still a bit more forward to reduce the voltage drop than the abomination that was installed by the PO.
 
Guys any Lithium above 150AH is capable of operating your windlass BUT your BMS most likely not as the 4-10x times voltage surge will fry it.
This is for all BMS in drop in batteries (unless explicitly stated) and all BMS that carry current like overkill or Dali and alike. Exception are non current carrying BMS like Electrodacus, one of the reasons I chose this BMS. And the same is also valid for the 2000W starter of your engine....so if you wanna emergency start your engine from the house, you need a BMS that can handle 600-800A spikes...or connecting it directly to LFP before the BMS if possible as a unsafe emergency work around...
And no the best winless battery is not a FLA which is in fact the worst due to its high reistance. LI suits very well as its able to instantly deliver the current the motor really needs but needs a BMS that can handle 300-500A spikes when operating the classic 1000-1200w windlass.
The best available starter and windlass battery are 6 Yinglong 40AH LTO cells in series without a BMS. If you want some extra capacity in case the anchor is heavyly stuck or you have 120m of chain take 12 cells in a 2p6S config. Not working with 24V as 11 LTO in series without BMS will differ to much over time, you can use the electrodacus BMS though with 24V LTO.
 
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The discharge rate on those LTO's is really impressive. Very interesting.
 
@mikefitz please expand on that - why do you think that lead acid is the way to go for a windlass battery? You've given no reason. As long as the battery is built to handle the discharge rate I don't think I agree.
I would like to understand this issue as well. I recently upgraded my windlass to a 1000w version ( Maxwell RC8-8) and looking for a solution to power it.

See this interesting article from Maxwell (pages 36-39) as to what a 1000w motor means in the context of a series wound windlass. They claim stall loads of 5000w for a 1000w windlass.

 
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