Lithium ion batteries.

[Lance Reynolds]

Please lets keep to Lithium IRON Fe or the poor press will surface again.
The last time I checked electric propulsion it was hard to keep enough power storage for lengthy cruising so you still need a fossil generator which I have to supplement my solar when ots cloudy for days .

[Sail power sail]

Lance. Agreed. Not looking to switch out diesel propulsion. Just current agm's for lithium ions

[Sail power sail]

My unresearched plan is to avoid weight and cost of a generator, but have ac if needed with extra capacity of LI. When I met with outremer reps in France they suggested such a systen

[BigBeakie]

Originally Posted by TheThunderbird

Pricing is still a factor.

It can be justified by electric propulsion. For service bank, it is just an option.

I think if you do your sums you might find that LiFePO4 (aka LFP, LiPo, etc.) are better value than you may think. Consider how much useable power you actually get over the life cycle of whatever battery you're considering. You may find, as I did, that Lead acid is false economy. LA is cheaper initial purchase price, but costs you more over equivalent life cycles.

For electric propulsion, there is no contest. Aside from the longevity of LFP compared to LA, the depth of discharge advantage of LFP, the lack of voltage drop of LFP vs LA, the HUGE charge acceptance rate advantage of LFP way shorter charging times), aside from all that, you also have the critical ability of high quality LFP ( and yes, there are significant quality differences in the different brands) to deliver the large amounts of amps/ unit time needed for full power use of electric motors. Lead acid is positively pathetic by comparison.

So, Lead is Dead. May sulphation death of LA batteries remain a thing of the past, at last!

[TheThunderbird]

Electric propulsion within the 30- 50HP range is a tested reality.

Of course, it is designed for medium range scope, not for long passages under power.

For a "true sailor" with little need to potter for long, it is a luxury yet intelligent option.

For heavier boats, complications raise with Voltages in excess of 70V, that which represent an hazard, ensuing expensive and not well tested layout of the grid/system onboard.

Hybrid system could then be considered. (Anyway, you need a DC Genny)

Awfully, very few marine engines have a power output, other than a pulley drive, with obvious draw back (max power extractable).

To my understanding, Lithium cost 4 to 5X more
Sure, you have longer cycle life and discharge capacity, allowing for lower Ah installed. Overall, it may be a thin advantage, yet based on expectations ON PAPER not yet widely tested (2000 cycles? Who did it?)

Points is, if you Value weight savings a lot (racers, small boats, very large house banks...) then it is a sensible option. With lead, l have at stake 1500$, not 6500$ :-)

PS having bought flexible solar panels by GIOCO SOLUTIONS, which work at 49% of rated capacity (in Sicily, flat site, 3hrs a day...), I don't buy in what sellers say about new technologies:-)

[Sail power sail]

Has anyone seen part 2 of the Impi video on Lithium Ion batteries. I thought part 1 was pretty good. It represents an independent view. I hate being educated by the people I am purchasing from as a rule.

[softdown]

The claims about lithium batteries are fantastic. What we do not have, at present, is a viably proven track record. It is easy to claim 15-20 years when you have been broadly available for much less than that.

They are small and lightweight and take a charge in an efficient manner. I might pay 3X but not ready to pay 4-5X. I'll wait until people prove that their lithiums lasted 3-4 times longer.

Youtuber SailingEmeraldSteel is getting 9-10 years from his Trojan T-105s by the way. I'll bet their fridge is pretty tiny. Only uses 120 watts for charging six T-105s as I recall.

[44'cruisingcat]

The cost benefit varies with location. It seems lead/acid batteries are available much more cheaply in the US.

In Australia, lithiums cost more than lead, but for a similar (useable) capacity bank, the cost difference isn't anywhere near as big. In my case, 50% more.

[kcj]

i replaced my 720 ah of AGMs with 600 ah of lifepo last Dec while on a mooring in KeyWest. I had been studying up on the conversion for some time. When I made the conversion i estimated the landed cost of the lifepo batteries to be about +20% more than the AGMs. that and a few hundred $$ and some time to modify the electrical system. toughest part of the conversion was getting the old AGMs off the boat.

best improvement i have made on the boat--i went from running the genset an hour or two a day (frig and freezer...)to basically being off the grid. and i can run the ac watermaker thru the inverter, and i run the genset more to heat water than to charge batteries...

with regard to life expectancy-- well the primary lifepo thread here is approaching its 6 year anniversary, and all reports therein are favorable. don't overcharge them, don't treat them like lead and they seem to do fine. I'm a convert--"lead is dead"


ymmv
good luck with decision

[downunder]

Originally Posted by Sail power sail

Has anyone seen part 2 of the Impi video on Lithium Ion batteries. I thought part 1 was pretty good. It represents an independent view. I hate being educated by the people I am purchasing from as a rule.

My understanding Part 2 has not been completed as yet.