Best battery for electric windlass

rcc

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Greetings,

I did a search on this and never really found a straight answer just dedicated to the windlass. I just upgraded our sail boat's solar and battery system to 2ea - 12v Lithium 280ah (total 560ah) house bank. These each have an Overkill BMS rated at 120amps ea for a total of 240 amp. The starter is a 12v LA 850 CCA. For next season I want to upgrade from my manual windlass to an electric.

I know a windlass power demand is more suited to LA but was wondering if anyone is powering their windlass with lithium. I am looking either the Lewmar H2 or H3 windlass.

Or, there is plenty of room in my sail locker right under and behind the anchor locker to set up a whole new battery dedicated to the windlass.

Thoughts?

RC
 

Ampster

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I know a windlass power demand is more suited to LA
I would start by clarifying the above since I think Lithium is more suited to the demands of a windless. No Peukerts, deeper discharge, lighter weight per kWh, some variations capable of discharging at high rates. The weight is an issue if you really do want to put the battery in the bow.
I don't know the details on those but Lewmar is a respected brand.
 

rcc

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I would start by clarifying the above since I think Lithium is more suited to the demands of a windless. No Peukerts, deeper discharge, lighter weight per kWh, some variations capable of discharging at high rates. The weight is an issue if you really do want to put the battery in the bow.
I don't know the details on those but Lewmar is a respected brand.
I mean that the power demand is similar to a starter battery, high amps for a short period of time then not used for long periods of time. Also it is likely the engine will be running when in use providing alternator amps/charging.
 

Ampster

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I mean that the power demand is similar to a starter battery, high amps for a short period of time then not used for long periods of time.
Precisely why Lithium is better suited in my opinion. It is capable if higher C rates and can be left partially discharged for longer periods of time.
 

deeuubee

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You should have no trouble running the windlass (110A) off those batteries.
Depending on the distance from the batteries to the bow it's gonna be a monster wire run, probably 2/0 awg.
 

Ampster

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Depending on the distance from the batteries to the bow it's gonna be a monster wire run, probably 2/0 awg.
I don't know what affect voltage has on speed but 24 volts could reduce the wire size needed. It does complicate charging so it might not be the best.
I think you were also suggesting using the new pack off the new 280 Ahr LFPs and that is 560 Ahrs and could work well. The wire size is insignificant compared to the weight saving in the forward part of the hull.
 

Cruiserguy

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We had a Lewmar H2 on our last boat running off our 2 8D battery bank mounted 25 ft. away and using #2 cable run from previous owner. The unit would pull over 80 amps when pulling 200 ft. Of 5/16 bbb chain and a 45 lb anchor when doing the last 30 ft or so of dead lift. Yes, the system worked but the motor never sounded happy....and with that long run had no kick to it.
Make sure you mount batteries that can handle that kind of draw and as close as possible, especially if you’re anchoring in deep water or using a long catenary where the motor tends to heat up. I hate lead acid, but I still run them for heavy motors like bow thruster, windlass and starters.
 

rcc

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What are the power requirements of the windlass you have in mind?
Both the H2 and H3 fall well within my current LFP bank range. The H2 draws 700w, 80amp and the H3 draws 1000w and 85 amp. We are on a 20,000lb 37' boat. The specs overlap and I would likely go with the H3 just because it is beefier and on Defender is only $50 more than the H2.
 

codfish

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I built a nice small LFP from 90 ah, Eve cells. They are rated at 3C. A plausible way to keep this remote battery charged is to tie it to the house LFP battery with a long run of smallish wire, say 14 awg. Pick the length of wire so that the intrinsic resistance of the wire limits the replenishment amps for this remote battery to the wire’s rating ( and properly fused on both ends). The battery will always exactly track the voltage on the house battery, just time lagged by a bit after you use it. This Only makes sense for intermittent use. And if you use a BMS on this battery make sure it disconnects the load not just the battery otherwise you will try to power the windlass on the long wire ( blown fuse).
 
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codfish

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The H3 has a retrieval speed of 59’ / min and 85 max amps. So 120’ of chain would only take 2 minutes, and under 3 ah. Easily replenished in a few minutes.
 

mjmcpo

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Curious what you decided to do about the windlass. Coincidentally, I’ve had a Lewmar H2 unboxed onboard for a year waiting for my battery upgrade. Finally in the process of adding 2 of the SOK 206Ah marine batteries and planning to add the windlass next. Will keep one of my LA for start battery. Sounds like no problem running windlass to house bank assuming properly sized cable (2 gauge for my distance). Let me know what you ended up doing. Thanks!
 

pretzel

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I built a nice small LFP from 90 ah, Eve cells. They are rated at 3C. A plausible way to keep this remote battery charged is to tie it to the house LFP battery with a long run of smallish wire, say 14 awg. Pick the length of wire so that the intrinsic resistance of the wire limits the replenishment amps for this remote battery to the wire’s rating ( and properly fused on both ends). The battery will always exactly track the voltage on the house battery, just time lagged by a bit after you use it. This Only makes sense for intermittent use. And if you use a BMS on this battery make sure it disconnects the load not just the battery otherwise you will try to power the windlass on the long wire ( blown fuse)
Interesting idea. And why not just make the windlass bank tied by a bigger conductor which would allow it to supplement the house bank.

Either way it would need its own BMS, so no wasted effort there.

Also, if you needed to take the house bank offline the windlass bank could fill in at a reduced capacity.

This is getting more interesting.
 

Sabre36

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Lewmar V2 windlass. Battleborn battery BMS kept tripping off when the windlass was under load. . We have customers who's windlass motors draw more tha300A.
 
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codfish

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Yes. stalled inrush is a real problem. The 90ah LFP battery I built does Not have a BMS. It does have a low cost active balancer. It regularly handles 300amp inrush of stalled starter motor. Pack level over / under is handled by chargers and alarms. The DIY cost of this was less than a comparable lead acid so I treat it the same.
 

captainrivet

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Due to inrush current won‘t work reliably with 120A overkill, you need a beefier BMS or one that doesn’t carry current like Electrodacus BMS. I run a lofrans cayman with 1000W with Electrodacus BMS and 840AH bank and inrush is sometimes above 300A. No problem for your 560AH LifePo4. A nice beefy cable to windlass is needed.
 

willo

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In my case? AGM. Unless you've gone full electric, you should be running your engine whenever you are running your windlass.
I've got two AGM cells - soon to have an isolator of some sort on them. They are my engine/windlass batteries.
If the engine is running, then I have something like 60A coming (haven't upgraded yet) from the alt on demand.

I also have a large 24v Lifepo4 bank. I haven't added a 24/12 charger yet. I'm leaning toward adding a smaller solar panel with a dedicated 12v controller just to maintain the AGM packs when I'm off shore power.

You may consider adding a capacitor (think audio systems 1 to 5 farads or so. This could take care of the current rush.
 

willo

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A bit ironically, I decided to put in a 24v alt + WS500 to charge my main pack. So I'm looking at making up 2 or 3 packs: Windlass, Engine Start and something to drive my new electric winches.
 

willo

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@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.
 
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