Advice on buying Lithium Batteries

[B27]

He said lithium house banks. I see no advantage in lithium starter batteries. Its an ideal application for lead. Top end production boats are starting to be sold with house lithium banks now so the move to lithium is going to happen

'Most Boat owners' includes a lot of people with small low tech boats.
A lot of RIBs, dories and sundry power boats.
The average boat in our river must be 20+ years old.
There's a big population of boats out there which, if they have a house battery, also view it as a back-up start battery.

Changes are happening, but take a very long time to work through the system.
I've got a few friends with motorhomes and vans of varying descriptions, an awful lot of shiny new ones leaving the factory with lead leisure batteries it seems? I think it will be some years yet before a lead leisure battery is hard to find or uneconomical to buy. fundamentally, they are cheap to make and highly recyclable.
OTOH, the UPS industry seemed to adopt LiFe quite suddenly.
It could be that better drop in solutions and price parity are not so far away.

 

[geem]

'Most Boat owners' includes a lot of people with small low tech boats.
A lot of RIBs, dories and sundry power boats.
The average boat in our river must be 20+ years old.
There's a big population of boats out there which, if they have a house battery, also view it as a back-up start battery.


It could be that better drop in solutions and price parity are not so far away.

That was the point of posting the latest utube video from Will Prowse. A pretty decent lifepo4 battery for not a lot of money.

My boat is 44 years old. Age has nothing to do with the conversion to lithium. The Tally Ho has just been rebuilt with lithium batteries.
Of course we are talking about domestic battery equiped boats boats ribs and dories.
You can charge a flat starter battery by combining it with your domestic battery via a simple switch. This will charge the lead battery. If the starter battery is defective such as having an internal short, it probably won't work

 

[B27]

....
You can charge a flat starter battery by combining it with your domestic battery via a simple switch. This will charge the lead battery. If the starter battery is defective such as having an internal short, it probably won't work

My friend's recent starter battery failure wouldn't be having any of that!

One downside of having a solar maintenance charger is that batteries don't fail by going flat, they seem to fail by just 'not being a battery any more'.
Maybe it should just have been replaced as being time served, or tested at intervals?

 

[Sea Change]

Possibly in the next few years, the peripheral bits like smart shunts and MPPT's and alternator adaptors will become cheap and that will create a turning point. But for the foreseeable, people are still buying lead batteries by the million.

Shunts and solar charge controllers are either required for your boat, or they aren't. Battery chemistry doesn't change that.
What is happening (in fact has mostly happened already) is that devices are sold with lithium compatibility already included.
So next time you upgrade your shore power charger etc, you'll find that it's now lithium compatible. And that will make a decision to swap your house bank that bit easier and cheaper.

 

[B27]

What shorepower charger?
The real issue is alternators.

 

[Sea Change]

What shorepower charger?
The real issue is alternators.

Yes, the link between the alternator and the lithium bank will generally remain as area where some additional equipment is required. Although we might find that marine engines start coming with lithium-ready alternators.

 

[dune16]

Yes, the link between the alternator and the lithium bank will generally remain as area where some additional equipment is required. Although we might find that marine engines start coming with lithium-ready alternators.

Newer boats might already be OK. My 2021 boar with 2 Yanmar engines already has Valeo alternators with internal temperature control as standard. If the lifepos start being too greedy causing the alternators to get too warm it will drop the amps back. This along with the agm starter batteries always being connected via argofet diodes (again, standard factory fit on our boat) means if the lifepo4 shutdown then any spike from the alternator would be absorbed by the agm rather than frying the alternator.

 

[migs]

Alternators with internal temperature control are a good idea., and our Volvo D2-40 came fitted with one as standard. The problem is that they charge the battery up to 14.4V and hold it here indefinitely - that's not good for LFP batteries.

You could set the BMS to cut out at say 13.8V, but this seems to be considered bad practice upon by some...

 

[dune16]

Alternators with internal temperature control are a good idea., and our Volvo D2-40 came fitted with one as standard. The problem is that they charge the battery up to 14.4V and hold it here indefinitely - that's not good for LFP batteries.

You could set the BMS to cut out at say 13.8V, but this seems to be considered bad practice upon by some...

Ours pumps out 14.2v but I agree, need to do something

 

[Sea Change]

Alternators with internal temperature control are a good idea., and our Volvo D2-40 came fitted with one as standard. The problem is that they charge the battery up to 14.4V and hold it here indefinitely - that's not good for LFP batteries.

You could set the BMS to cut out at say 13.8V, but this seems to be considered bad practice upon by some...

That's only 3.6v per cell, not the end of the world. And who motors indefinitely?
A lot of established best practise around LFP is based on the assumption that they are an expensive investment which needs treated with kid gloves. At today's prices, that's no longer true.

 

[B27]

Yes, the link between the alternator and the lithium bank will generally remain as area where some additional equipment is required. Although we might find that marine engines start coming with lithium-ready alternators.

I've got a 2005 car with a smart alternator.
Boat engines are not at the forefront....

My boat has very little space around the alternator, so upgrading will be difficult.
I suspect that's quite common.

 

[Sea Change]

I've got a 2005 car with a smart alternator.
Boat engines are not at the forefront....

My boat has very little space around the alternator, so upgrading will be difficult.
I suspect that's quite common.

There are several ways of addressing this problem.

1- ignore it, charge your domestic bank from solar alone.
2- hybrid LA-Li system
3- DC-DC charger
4- new regulator or new alternator

There's no need to assume that converting to lithium is scary and expensive. But you do need to think about how you use the system and find a solution that works for you. I knew I was sailing to sunnier climes, and fitting a lot of solar, so option 1 was perfect for me.

If you have a smallish boat with little space for solar, and mostly do short trips in the UK with lots of motoring and shore power, then you'll choose a different solution, which might well be lead acid.

 

[PaulRainbow]

There are several ways of addressing this problem.

1- ignore it, charge your domestic bank from solar alone.
2- hybrid LA-Li system
3- DC-DC charger
4- new regulator or new alternator

There's no need to assume that converting to lithium is scary and expensive. But you do need to think about how you use the system and find a solution that works for you. I knew I was sailing to sunnier climes, and fitting a lot of solar, so option 1 was perfect for me.

If you have a smallish boat with little space for solar, and mostly do short trips in the UK with lots of motoring and shore power, then you'll choose a different solution, which might well be lead acid.

Thank heavens, at last, a Lithium user who understands that for some people Lead Acid is still a possible solution. Well done

 

[geem]

Thank heavens, at last, a Lithium user who understands that for some people Lead Acid is still a possible solution. Well done

Said by a lead user

 

[PaulRainbow]

Said by a lead user

But one who has also fitted Lithium. I have also been asked by customers about Lithium and when asking them how they use their boats have suggested alternatives.

Plenty of times an alternative has been as cheap and simple as fitting an extra battery. Boats kept in marinas and used at weekends, marina hopping, or one night at anchor rarely benefit from Lithium. Your usage is completely different and Lithium makes perfect sense, for you.

Try not to lose sight of the fact that others use their boats differently and for many of them, Lithium makes no sense at all.

I currently use lead because Lithium makes no sense for me, at the moment. Everywhere i go i have two engines running, with 60a 24v alternators and adequate LA storage. In the two years that we have owned this boat we have never, ever, been short of the power we need.

 

[geem]

But one who has also fitted Lithium. I have also been asked by customers about Lithium and when asking them how they use their boats have suggested alternatives.

Plenty of times an alternative has been as cheap and simple as fitting an extra battery. Boats kept in marinas and used at weekends, marina hopping, or one night at anchor rarely benefit from Lithium. Your usage is completely different and Lithium makes perfect sense, for you.

Try not to lose sight of the fact that others use their boats differently and for many of them, Lithium makes no sense at all.

I currently use lead because Lithium makes no sense for me, at the moment. Everywhere i go i have two engines running, with 60a 24v alternators and adequate LA storage. In the two years that we have owned this boat we have never, ever, been short of the power we need.

Paul, I understand. Often people work on the basis of if it's not broken, don't fix it. I get it.
You don't need to see the advantages. That is the beauty in many ways. It can be fit and forget for many people. They would just be there and work, day after day , year after year after year. You don't need to see the advantages but they would still be there.
No drop in coulomb efficiency, no loss of AH capacity, far less effected by heat than lead, better charge acceptance rate, no sulphation, no need to get to 100%. These benefits apply to all cruisers, not just those living aboard for months at a time. But yes, some will just put another lead battery in when the old one dies and that's fine

 

[Pearldiver]

Can I ask about insurance? In other forums I have seen people saying they have had exclusions imposed on fire risk when they fitted lithium or lithium phosphate batteries. Anyone encountered this - or better still, overcome it with an insurer?

 

[geem]

Can I ask about insurance? In other forums I have seen people saying they have had exclusions imposed on fire risk when they fitted lithium or lithium phosphate batteries. Anyone encountered this - or better still, overcome it with an insurer?

Insured with Pantaenius. No problem.
I think it is a developing situation though. Most insurers are ignorant of the issue and look to minimise their risk, of course

 

[Sandy]

Can I ask about insurance? In other forums I have seen people saying they have had exclusions imposed on fire risk when they fitted lithium or lithium phosphate batteries. Anyone encountered this - or better still, overcome it with an insurer?

I'm with Pantaenius they emailed me in the early part of 2024 asking that if you have lithium they must be advised.

 

[Sea Change]

I'm with Pantaenius they emailed me in the early part of 2024 asking that if you have lithium they must be advised.

Did they mention anything about lithium batteries that aren't permanent installed? Things like ebikes are far, far higher risk than a correctly installed LFP bank.