Lithium batteries with Windlass

[offpist]

Been using Lifepo4 for windlass/start/thruster for a while.
Works great.

I use 115AH in 4S2P setup.

[zboss]

Originally Posted by offpist

Been using Lifepo4 for windlass/start/thruster for a while.
Works great.

I use 115AH in 4S2P setup.

What is interesting is that you are showing you have actually pulled down over 500 amps at some point.

[offpist]

Yes, for two seconds.
Could be the windlass, the split second when it almost comes to a stop.

It really holds the voltage well on high loads, and for me it was easier to have only Lifepo4 on-board instead of mixing battery types.

[zboss]

Originally Posted by offpist

Yes, for two seconds.
Could be the windlass, the split second when it almost comes to a stop.

It really holds the voltage well on high loads, and for me it was easier to have only Lifepo4 on-board instead of mixing battery types.

Or maybe when its trying to pull an anchor out.

Even over 200 amps is amazing... we don't have any time over 200 amps. We didn't have any time over 100 amps until we got our electric windlass. We used it for two months in the Bahamas and racked up about 5 minutes above 100.

[offpist]

Its not only the wind lass connected.

-Start main engine.
-Start generator.
-Wind Lass
-Bow thruster.

The bow thruster uses well over 200A.

[JBPohle]

Hey Offpist, what do you collect and output the data with. I like the information and how it is presented.


Sent from my iPad using Cruisers Sailing Forum

[offpist]

Originally Posted by JBPohle

Hey Offpist, what do you collect and output the data with. I like the information and how it is presented.


Sent from my iPad using Cruisers Sailing Forum

I use the Mastervolt Mastershunt.
It does not have controll of each cell like an BMS, but it does have Lithium program so it is very accurate at calculating SOC% and it can also be setup to give an alarm if over or under voltage.

I also have an Masterbus to NMEA2000 converter, so so i display all info on the Raymarine E127.

-Voltage service battery.
-Ampere service battery.
-SOC Service Battery.
-Temperature Port Alternator.

-Voltage start battery.
-Ampere start battery.
-SOC Start Battery.
-Temperature babord Alternator.

The Mastervolt Alpha Pro II regulator communicates with the Shunt, so alternators are seeing the voltage directly on the battery.
This makes a lot of sense since i have one 100A Balmar and one 120A Balmar. Even with 70mm2 cable there will be some voltage drop.

[zboss]

I also have a mastervolt but found that it did NOT do a good job at calculations. In fact, it shows my voltage to be off by .02 volts. May not seem like a big deal to some folks but I could never figure out why I could only charge to 4.6 volts when I had the charger set to charge to 4.8 volts.

I have since complemented it with a Balmar SmartGauge which we like much better and does a better job at calculating battery levels.

FYI - my mastervolt easyview recently went bad (display bonkers) and when replaced with a new one (that took about 2 minutes) and it maintained all the history and other info, so I think that data is actually stored in the shunt or the charger, not the panel display.

[OceanPlanet]

We have been using Super B starting batteries for starting/power applications. Have been good and very lightweight however the chemistry is low density in Ah's. Which would be an issue if you needed to run a windlass for an extended time. We'll soon be announcing new Li batts with higher energy density and with internal circuitry that can handle starting/windlass currents yet still protect the battery.

[zboss]

Originally Posted by OceanPlanet

We have been using Super B starting batteries for starting/power applications. Have been good and very lightweight however the chemistry is low density in Ah's. Which would be an issue if you needed to run a windlass for an extended time. We'll soon be announcing new Li batts with higher energy density and with internal circuitry that can handle starting/windlass currents yet still protect the battery.

Bruce that's great news, I've been very very happy with the service you have provided so far.

The Genasun batteries are way way expensive.

I think Mainesail's explanation on an external connector makes a lot of sense. It seems to me that there are quite a few changes that would need to be made if we switched over to lithium at some point.

I am wondering if someone can answer a question regarding charging speeds.

How much actual benefit - in terms of reduction in solar/wind charge time - can one expect from a lithium vs. a lead acid? Sometimes we don't get a full charge on a perfectly sunny day using our lead acid batteries - in the winter there is just not enough time in the day to complete charging. Also, "full voltage" on the Trojans are much higher than that of other batteries, so it takes them longer to get there than other batteries... or am I misunderstanding how that works?

What I am getting at is this... our fridge is old. The cost of us tearing out the old fridge and building a new fridge with more insulation is in the thousands of dollars, basically in the range of the same cost of just buying a lithium system. Obviously there are benefits to both but what is the best bang for the buck when costs are the same - increasing storage and reducing charge time, or reducing consumption? In our case, we MAY be able to reduce our fridge consumption in half - to maybe 60 amp/hours a day vs. 120.

But increasing our usable storage capacity maybe INCREASE our capacity by 120 amp hours, providing us a 60 amp/hour windfall for the same price.

[OceanPlanet]

Well, Ah's are Ah's, however Lithium batteries are more efficient than Pb, being almost 100% efficient as far as amps in/out. However that is not truly 100% in watts, as the charging voltage is a bit higher then when discharging. So even if the same Ah's go in as out, the watts going in are more than going out.


Pb batteries can actually approach 100% efficiency (again talking in Ah's, not true watts) if charging/loading in the middle range of capacity. Absorption charging is very inefficient as energy is lost in heat and gassing (even sealed Pb will gas internally). But of course if you don't do the absorption charging then most Pb batts will get permanent sulfation and capacity will spiral downwards.


To answer your question as to whether going Li would allow you longer run times for the same amount of charging...slightly, yes. However maybe not as much as you are looking for.

[OceanPlanet]

I forgot to mention that the only Pb batteries that we know of that won't suffer permanent sulfation damage from extended PSOC (Partial State Of Charge) cycling (that is, not going through enough absorption time to fully charge and desulfate the negative plates) are the Firefly MCF (Microcellular Carbon Foam) AGM's.


Now if we could get the Firefly factory to keep up with the orders we already have...