Cost of LiFePo4 vs Lead in Your Market

[ranger58sb]

Originally Posted by a64pilot

Depends on use, when I got mine I spoke with them at Lifeline and was instructed as to their use.
What I said was my use was partial cycling every day to about 90% SOC, but once a week a good, full charge and once a month equalizing (Lifeline’s recommendation).
He told me that in five years I’d be calling him back for another set.

It’s the PSOC that “gets” them, reduce that and of course they will go longer, don’t equalize once a month and they won’t last as long.
I actually get them fully charged twice a week if not more, and have spent way more time on Shorepower than originally planned, so maybe six or seven years?

Yeah, I spoke with them, too, before pulling the trigger... because that bank is also an engine start bank and I wanted to make sure combined cranking amps a) would be sufficient and b) the batteries wouldn't be adversely affected (at least too much) in that kind of service. All good.

But our charging situation is likely easier thatn yours would be on our batteries... We got 11 seasons from the previous 3x Odysssey PC-2150 AGMs that made up that bank... likely because our heavy battery use (electronics and fridge) is mostly while underway unless we have the genset running at the same time. We seldom anchor out for more than a week straight... and even then, we run the genset 2x/day anyway, to cook, heat water, etc.

-Chris

[Singularity]

Originally Posted by Jerry Woodward

Thanks, that is a good price, but if we're comparing costs, we should also include the cost of the BMS and hardware in a DIY setup. Can you share your total cost? Assume the charging sources are all adequate for LFP. Thanks.

Precisely which costs are you looking for? The $17 cost for angle aluminum? There are many options for BMS, from next to nothing to thousands of dollars depending on your comfort level with technology, your specific type of charging system, etc. Cables/connector costs are roughly equal amongst systems. There's nothing hidden or mysterious mysterious here.

[Dockhead]

Originally Posted by mikedefieslife

In my case I’m looking for around 250 usable ah at 12v. I currently have a 675ah bank but it is 5 years old or more.

4x 300ah 3.2 winston cells are €1.580

2x 554 Rolls 6v FLA are €710.

Based on 250ah
Lithium is €6.32 per ah
FLA is €2.84 per ah

The Rolls batteries are guaranteed for 7 years. The Winston cells are DIY so guarantee is limited.

The Winston cells weight 40kg total. The Rolls 112kg. The weight advantage is massive. Though makes little odds considering i have 200kg of batteries at the moment. So either is a saving.

Most likely possible to get a good 10 years out of either set. As much as I’d like the Lithium bank, once the cost per ah in addition to the capital outlay isn’t attractive to me being the reasonable economic man.

Please do tell me if I’m missing something.

Sounds reasonable to me


If you don't need any of the other advantages of lithium, then your analysis looks sound.

[roland stockham]

Trying to argue for litium seems a nonsense and pointless. The numbers given are about 1200 for conversion plus 2000 for the bank. To justify this on purly ecconomic grounds this would need a life expectency of around 30 years. How many people actually keepa boat that long! Also if you consider the interest on the extra investing the money for the life of the FLA bank would go a long way to replacing the bank when needed.


There may be good reasons for moving to lithium but this is no one of them. It strikes me that there maybe an element to trying to justify the option

[newhaul]

Originally Posted by roland stockham

Trying to argue for litium seems a nonsense and pointless. The numbers given are about 1200 for conversion plus 2000 for the bank. To justify this on purly ecconomic grounds this would need a life expectency of around 30 years. How many people actually keepa boat that long! Also if you consider the interest on the extra investing the money for the life of the FLA bank would go a long way to replacing the bank when needed.


There may be good reasons for moving to lithium but this is no one of them. It strikes me that there maybe an element to trying to justify the option

a good reason for conversion
https://relionbattery.com/blog/lithi...ity-efficiency

[john61ct]

Originally Posted by roland stockham

Trying to argue for litium seems a nonsense and pointless

That may be true from your POV.

Maybe decent deep cycle FLA is cheap in your location's market.

In the rest of the world it can cost 3-5x more than where you are, and maybe good LFP systems are available for a lot less than they are in your area.

Some owners are willing to spend a lot to reduce the weight of their boat.

Also there are classes of boat owners that spend $50K a year on their boating expenses, so just delaying another purchase by a year will fund a big LFP bank without any financial strain.

So you are right in the sense that they are not (yet) right for everyone.

But it is certainly not the case that they don't make sense for anyone.

[Jerry Woodward]

Originally Posted by Singularity

Precisely which costs are you looking for? The $17 cost for angle aluminum? There are many options for BMS, from next to nothing to thousands of dollars depending on your comfort level with technology, your specific type of charging system, etc. Cables/connector costs are roughly equal amongst systems. There's nothing hidden or mysterious mysterious here.

I never meant to imply there was anything hidden or mysterious. I'm just trying to get a realistic idea of what a 400ah LFP system will cost me if I go DIY. I realize there is a wide variety of options for BMS, but from all I read, it is best practice to get a good BMS that will allow individual cell monitoring and prevent over and undercharging. Curious what you are using and how well it works.

[roland stockham]

Originally Posted by newhaul

a good reason for conversion
https://relionbattery.com/blog/lithi...ity-efficiency

The comments page has an excellent note that exactly makes my point
"12 volt 400 A/H lead acid battery costs about NZ$800. Life... about 7 years.
12 volt 400 A/H Lithium phosphate battery costs NZ$4840. Life... unknown but supposedly about 10 year."


As a note thought the life expectency of 6v FLA is typically above 10years if they system is correctly sized and set up



I have seen some excellent systems on larger high power use and all electric boats. Wher the requiremnt is for a bank in excess of 1000a/h and particularly where currents of above 50a (12v) are drawn for more than 10min or form a common part of the discharge pattern lithium does look like it has advantages. It seems that in this case, partculrly on a cat which can fit a very large solar array this may avoid needing to fit a generator and the ecconomics make more sense.


The other place where Lithium is a major advantage is for racing where the weight advantage is significant. On a cruising boat however it is irrelevent.

[john61ct]

Originally Posted by roland stockham

"12 volt 400 A/H lead acid battery costs about NZ$800. Life... about 7 years.
12 volt 400 A/H Lithium phosphate battery costs NZ$4840. Life... unknown but supposedly about 10 year."

Yes in that scenario makes little sense.

The supposedly is wrong, properly cared for LFP bank may last 20 or more, 10 is very low.

If EoL is 75% SoH, very few low-cost GCs like Deka will last more than 5 years.

Coddled Rolls-Surrette, maybe.

So, just like all statistics, devil is in the details.

Over-generalized sweeping statements do not help.

[2geer]

Being an owner of a set of aging Lifeline GPL-4CT batteries and facing the decision of what to replace them with, I for one would like to know if LiFePo4 with only internal BMS (Battle Born etc) can be made to work given the the types of events that can kill them (over voltage/over charge etc). I think many of us would like to make the transition but our unable to justify the cost of a complete redesign of our existing equipment. I run Victron Multiplus units for charge/invert btw... Obviously to make that transition depends a great deal on what people currently own however I have read other threads that suggest that internal BMS without external signaling should not be considered.

And - if the answer(s) to the above came from people that do not have a direct commercial interest in the sale, consultation and/or design of marine electrical systems - it would be preferable.

Thanks,

dg

[DeepFrz]

Dockhead, check out "Journey with Jono" on youtube. He has a few vlogs on his Lithium installation including diagrams and some useful money saving tips, charging with alternator, etc. He is on a narrow boat in jolly old.

[lateral]

Originally Posted by roland stockham View Post
"12 volt 400 A/H lead acid battery costs about NZ$800. Life... about 7 years.
12 volt 400 A/H Lithium phosphate battery costs NZ$4840. Life... unknown but supposedly about 10 year."]

And, My US batteries 464Ahr FLA cost $1300NZ ($800 ???)
as ppl have said you could probably get away with half sized LFP
equals , say $3000NZ.
Doesn't look so bad now with the other advantages.

[elandra65]

Has anyone considered what happens when you get hit by lightning. I have been hit and the only electrical stuff that survived were the pb batteries and some simple circuits. Everything dc with a chip died which would of included any fancy BMS etc. Just saying it is a consideration esp if you are remote like I was.

[newhaul]

Originally Posted by elandra65

Has anyone considered what happens when you get hit by lightning. I have been hit and the only electrical stuff that survived were the pb batteries and some simple circuits. Everything dc with a chip died which would of included any fancy BMS etc. Just saying it is a consideration esp if you are remote like I was.

that's what lightening protection system is for. A big plate on the outside of the hull to ground your mast and rigging to . That and prayer.

[a64pilot]

No, lighting can and will take out anything, protection systems have not been shown to do anything.
If they did your Insurence would either require it or give you a discount for having it (my opinion)

It would seem prudent to take spare electronics as required to keep your bank functional, or learn to do without electricity.