Is a new-build without lithiums just plain stupid???

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Mako

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Plenty of threads on TF and CF regarding switching over to LiFePO. However for a new-build I wonder what the justification/advantage would be to stick with FLA instead of going lithiums. A difference in cost of a couple grand would be insignificant to the overall cost of build.

I still think that old fashioned deep cycles are more durable. A concern I've had in the past is that the charging BMS could be taken out by lighting or nearby strikes. However, with external or removable BMS, spares could easily be kept in your Faraday box.
 
I would avoid FLA, personal preface, and go to AGM
 
I understand going low/no maintenance, but why even AGM vs lithium in you opinion?
 
I understand going low/no maintenance, but why even AGM vs lithium in you opinion?

Maybe in my next life when the technology has been (IMO) perfected and the price drops significantly.
Your boat, your money.
 
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If weight and space aren't a limitation, AGM or FLA has the advantage of simplicity, being that their charging needs are less complex. And they'll probably come out a bit cheaper. But that's about it for advantages I can think of.
 
I ocassionally bump into knowledgeable people who believe lithium "just isn't 'there' yet." I'm not sure what 'there' looks like so maybe they are just cautious, perhaps overly so.

For house batteries, I cannot think of a reason not to go LiFePO4, though I confess I had never thought of a lightning strike whacking the BMS. I think the better question is configuration. Daisy chain multiple off-the-shelf batteries, or do a custom build. There may also be a case to be made for a 48v battery bank, especially if meaningful solar will be installed.

Recently saw a knowledgeable review of a SOK LiFePO4 12v/200ah battery for just over $1000. Reviewer was enthusiastic about building quality. Price is definitely coming down.

https://www.sokbattery.com/products/12v-206ah-lifepo4-lithium-iron-phosphate-battery-pack


Peter
 
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While there are clearly advantages to lithium batteries, I can see situations where one might choose another chemistry.

They might not be my choice for a boat in the extreme Northern or Southern hemispheres.

While the BMSs seem reliable, I could see someone planning to cross oceans, choosing a different chemistry to avoid the electronics. This is similar to people choosing mechanically injected motors versus electronic common rail diesels.

Ted
 
Being old school I prefer flooded. Simple, reliable kiss tech, easliy replaceable and long lasting for the cost. I get 6 to 10 years from them. Will batteries costing ie 3x more last 3x more? Also they use no toxic rare earth metals so are 100 percent recycleable and 100 percent USA made.
Your boat your choice.
 
No, I don't think it is stupid to forgo lithium but it would probably be unwise to at least consider them.

If you are planning to go without a generator or really use one minimally, spend a lot of time anchored out and have loads that need to run off of an inverter, lithium really provides a great solution.

If you are a boater that is in a transient slip at least 50% of the time when traveling or you are quick to fire up the generator and run the air conditioning, lithium is of relative less benefit to this style of boating.
 
For me it would depend on the expected use of the boat. If the boat is in weekend or seasonal use (and therefore stored for longish periods) AGM makes a lot of sense, because they require no care in storage - just float charge and walk away. LFP on the other hand should be stored nearer 50% charge, and cycled every so often to maintain the cathodes. This is harder to accomplish, requiring some active maintenance with today's state of the art BMS'.

On a liveaboard, I'd go with LFP since the batteries are in cyclical use, or at least you are present to monitor and maintain the battery.

My boat is stored for 6 months + each winter, 1000 miles away from me. When I replaced the batteries this year I used AGMs for that reason.
 
Imagine you are enjoying life in the Marquesas, or for that matter the Sea of Cortez, or the Exumas and you lost a specialized LiFeP04 battery.

Depending on how you designed your bank that might just be a pretty darn big deal, especially with the larger LiFeP04 batteries coming to the market.

How difficult will it be and how long will it take to get a replacement? :blush:

Now imagine the exact same scenario and you have a bank of FLA batteries, probably something along the lines of a L16.

How hard would it be to replace that battery? Not hard at all. You will probably find someone with it in stock in any decent sized town anywhere. :)

Now take this even further.... While you are waiting for your new LiFeP04 replacedment to be shipped to you, things are probably not so much fun on your boat. Why??? Because many LiFeP04 systems are designed to operate on the edge of their capacity.

Now take that FLA bank and imagine how things would work. Well, since you only generally operate your FLA bank to 50% capacity to increase it's lifespan you can still operate as normal until you get a replacement knowing you are simply reducing the effective life of your battery bank that cost you all of a couple thousand dollars in the first place. In the final analysis you probably won't see much if any difference in lifespan anyway since you will have a replacement battery installed as soon as you make port.

Boats are not just about having the latest greatest. They are about having a functional system that can survive things that happen to all equipment at sea.
 
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that's exactly what I was thinking...availability.
FLA, or I suppose AGM in a similar way, is much more proven and established.
Could even go to an auto parts store and get a starting battery in a pinch!
 
I replaced the house bank in September and chose to switch from FLA to Fireflys. Thought about Lithium and decided the simplicity of the Fireflys was a better match. 6 years ago the Fireflys were newer technology, now more proven. I see the Lithium as a good choice, but see the players and models changing so frequently that I didn't feel as comfortable as first picking Trojan T-105s and later the Fireflys.

Ted
 
Imagine you are enjoying life in the Marquesas, or for that matter the Sea of Cortez, or the Exumas and you lost a specialized LiFeP04 battery.

Depending on how you designed your bank that might just be a pretty darn big deal, especially with the larger LiFeP04 batteries coming to the market.

How difficult will it be and how long will it take to get a replacement? :blush:

Now imagine the exact same scenario and you have a bank of FLA batteries, probably something along the lines of a L16.

How hard would it be to replace that battery? Not hard at all. You will probably find someone with it in stock in any decent sized town anywhere. :)

Now take this even further.... While you are waiting for your new LiFeP04 replacedment to be shipped to you, things are probably not so much fun on your boat. Why??? Because many LiFeP04 systems are designed to operate on the edge of their capacity.

Now take that FLA bank and imagine how things would work. Well, since you only generally operate your FLA bank to 50% capacity to increase it's lifespan you can still operate as normal until you get a replacement knowing you are simply reducing the effective life of your battery bank that cost you all of a couple thousand dollars in the first place. In the final analysis you probably won't see much if any difference in lifespan anyway since you will have a replacement battery installed as soon as you make port.

Boats are not just about having the latest greatest. They are about having a functional system that can survive things that happen to all equipment at sea.

We have ours done as 280ah@24v
We have done three of them, each with their own BMS and MRBF

We could run the boat comfortably enough on one

As for cost, 820ah @ 24v of LFP has cost less to build than 840ah@24v of AGM

The other advantage of LFP is at a later stage I can add additional batteries to the bank, something that is not recommended with AGM or lead.
Usually if a cell goes bad the whole bank need replacing
 
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While there are clearly advantages to lithium batteries, I can see situations where one might choose another chemistry.

They might not be my choice for a boat in the extreme Northern or Southern hemispheres.

While the BMSs seem reliable, I could see someone planning to cross oceans, choosing a different chemistry to avoid the electronics. This is similar to people choosing mechanically injected motors versus electronic common rail diesels.

Ted

BMS is not necessarily required
Plenty of users running LFP without by keeping the charge "between the knees"
 
The power density of Li-ion batteries is, in my opinion, not worth the cost or risk associated with them. Good points have been made about difficulty of replacement should one fail. However these batteries can also present a fire risk if they overheat. Overheat can occur if they are overcharged such as a faulty charge regulator. If they do catch fire they also release toxic fumes (fluoride gas), which in an enclosed area such as boat is very dangerous.

AGM is a good compromise which won't leak but doesn't have the inherent safety risks of Li-ion. Also AGM's are relatively available and if needed a flooded battery can replace a dead AGM (though charging profiles are somewhat different).
 
We have ours done as 280ah@24v
We have done three of them, each with their own BMS and MRBF

We could run the boat comfortably enough on one

As for cost, 820ah @ 24v of LFP has cost less to build than 840ah@24v of AGM

The other advantage of LFP is at a later stage I can add additional batteries to the bank, something that is not recommended with AGM or lead.
Usually if a cell goes bad the whole bank need replacing

I can only compare what is fully developed on the market today from a reputable manufacturer.

Battleborn batteries has a 400AH 12 volt system on sale today for $3796

I found Crown 420 AH batteries for $339 each. four of them would give a 840AH bank for $1356.

Those are todays prices for off the shelf reputable manufacturer, no engineering required batteries.

The OP asked for reasons not to go LiFeP04 and there are are valid tradeoffs.
 
In life cycle costs on a boat you are going to keep for awhile, the LFP will be cheaper than FLA or AGM. That used to be a theoretical prediction, but they have been around long enough now that it is proven experience. LA wins on initial capital investment, but loses by replacement time.
 
Those are todays prices for off the shelf reputable manufacturer, no engineering required batteries.

The OP asked for reasons not to go LiFeP04 and there are are valid tradeoffs.

You buy AGM or LA and you need to connect them all up with cable or busbars to make a usable battery bank

You buy LFP cells and you need to connect them all up with cable or busbars to make a usable battery bank

Same "engineering"
 
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I’m not being sarcastic I’m just wondering what is consuming most of your power I’m assuming you’re not air conditioning with your battery bank or heating water or heating with electricity .I’ll get by fine with very little .I’m just not quite understanding what you need all that power for Refrigerator ,heavy use of the microwave I honestly don’t know, On a new build hydraulic thrusters will definitely be an option .I like them better anyways like I said I’m not being sarcastic I truly don’t understand
 
For those mentioning fire concerns with lithium, that's more of a concern for Li-ion batteries. The stuff typically used in boats is LiFePO4, which is a very different chemistry. Energy density is lower than Li-ion (but still much higher than lead acid) and LiFePO4 doesn't have the big fire danger of a large Li-ion battery.


I’m not being sarcastic I’m just wondering what is consuming most of your power I’m assuming you’re not air conditioning with your battery bank or heating water or heating with electricity .I’ll get by fine with very little .I’m just not quite understanding what you need all that power for Refrigerator ,heavy use of the microwave I honestly don’t know, On a new build hydraulic thrusters will definitely be an option .I like them better anyways like I said I’m not being sarcastic I truly don’t understand

On my boat, the biggest power consumers when we're on battery power are the fridge and the ice maker (via the inverter). We could easily go without the ice maker, but we have the means to power it easily enough and it came with the boat, so might as well use it. Other than that, power is mostly for lights, fans, the onboard wifi setup, charging phones, etc. Oh, and it's nice and convenient to just plug in the coffee maker and use it on inverter/battery power in the morning. We've got far from the biggest electrical system on this forum, however.

If space, weight capacity and budget allows, it's nice to have an electrical system that can power all the stuff you want (which may or may not be a lot depending on your boat and lifestyle), rather than constantly being limited by a small electrical system.
 
I’m not being sarcastic I’m just wondering what is consuming most of your power I’m assuming you’re not air conditioning with your battery bank or heating water or heating with electricity .I’ll get by fine with very little .I’m just not quite understanding what you need all that power for Refrigerator ,heavy use of the microwave I honestly don’t know, On a new build hydraulic thrusters will definitely be an option .I like them better anyways like I said I’m not being sarcastic I truly don’t understand
What you don't understand is people have different needs, priorities and opinions that yours.
Different strokes....
 
How much do you expect to use the batteries? If you overnight connected to shore power most of the time, then your batteries will only ever get used to carry you through short periods of no shore power or no engine running. It's hard to get excited about optimizing batteries for that use.


If, on the other hand, you anchor out a lot, especially for multiple days at a time, then I think LFP will bring a lot of value to your day to day life. People say they require more attention to charging and maintenance. I disagree. They require much less attention to charging and maintenance. The really are better in almost every regard.


But there are a few things to think about. Can you locate them somewhere in the boat where they will stay above 0C/32F, and stay below 40C/105F? Mine are in the laz, and the temp control is very good. The surrounding water keeps it cool enough in the summer, and residual heat from my heater keeps it warm enough in the winter. But if you store your boat in a freezing climate in the winter, you may want to remove the batteries. They can be stored below freezing, but can't really be operated that cold.


As for cost, I would ignore it. I know, easy to say about someone else's money, but hear me out. In a new build, it's pretty easy to accommodate things like operating temp range. Also, the incremental cost will be negligible. You can argue about how much more expensive LFP is to purchase. But you can also argue how much cheaper they are over time. Both are true, and are used to arrive at whatever answer someone is looking for. For me, every time I use the batteries, which is frequently on the boat and every day in my house, I'm reminded how much they are worth every penny I paid for them.


I share other's concerns over BMS electronic failures taking out the batteries, but in both of my installations, I found pretty workable safeguards. In my home system that is also home made, I out in a manual override switch that forces the batteries on regardless of what the BMS thinks. It also let's me work on the system and keep power on while doing so.


On the boat I went a bit fancier and have two separate battery banks, each with it's own BMS. So if one fails in any way, I can keep running on the second one. Additionally, I have manual parallel switches that let me switch either of two start banks in as the house bank. The start banks are AGMs, so I don't have all my eggs in the LFP basket.


In a new build, it's really easy to incorporate stuff like this to achieve the level of redundancy that you want.
 
@Scooby, you commented about hydraulics for a new build for thruster and windlass. However I don’t believe in mixing too many systems for small boats (say 65’ or less) as it’s unnecessary. Would prefer to keep to all electric, with possibly some propane in the galley to augment induction.

My wife likes both for different uses. I like redundancy.
 
From what I see the choices are similar to electronics.

Some folks are happy with a compass and a chart kit, others require a 24 inch flat screen with multiple backups.

Lithium batts seem to be a boating hobby for folks that enjoy the tech side.

WLA seem to be for the folks that just want to go cruising .
 
In life cycle costs on a boat you are going to keep for awhile, the LFP will be cheaper than FLA or AGM. That used to be a theoretical prediction, but they have been around long enough now that it is proven experience. LA wins on initial capital investment, but loses by replacement time.
And will you own the boat or even live long enough to break even on those fancy LFP batteries? And fire? If one of those LFPs gets going, abandon boat cuz you won't be able to squelch it. In short order, it may even burn its way through the bottom of the boat. Amuse yourself and Google electric car fires and how 10,000s of thousands of water hosed by firefighters does almost nothing to knock down the fire. With all of the angst boaters commonly have about unlikely catastrophes, like we MUST have dual Racors, this event, burning LFPs, is far more likely and potentially DEADLY to boot unlike having to change a filter in a pitching seaway. Yet, from the proponents of LFP technology I have seen ZERO concern or discussion or analysis or even rationalization.

If a FLA battery fails, remove it from the bank (or two if a 6-volt array) and carry on till you can get to a port and go to Costco or Sam's Club.
 
And fire? If one of those LFPs gets going, abandon boat cuz you won't be able to squelch it. In short order, it may even burn its way through the bottom of the boat. Amuse yourself and Google electric car fires and how 10,000s of thousands of water hosed by firefighters does almost nothing to knock down the fire.


I don't know of a single electric car using LFP batteries. As far as I know, they're all other lithium chemistries (which are more energy dense, but much less safe from a fire perspective). That danger is one of the big reasons why LFP became common over the other chemistries for boats. It's much safer at the expense of lower energy density (but it's still a big improvement over lead acid in that department, so good enough for boat use where you're not counting every last pound).
 
Yes, when doing a new build plan on a very capable Li battery complete and integrated system. But and a very big but, have a very good charging and inverter system. Add to it complete redundancy for:
- engine and generator starting,
- inverter failure and bypass
- segment separation on Li strings
- large engine driven Alternator or DC power source
- battery temperature cooling/heating

Which raises a question, are builders and designers up to the task of a good Li system? This would be a serious Achilles heel IMHO especially given the lack of agreed upon electrical system best practice design by current builders and slow to the party ABYC recommendations for Li systems.

What would be helpful on this subject would be comments regarding problems and solutions experienced Li system cruisers have endured. Since these are virtually non- existent on TF does this mean Li systems are that good or users are quiet regarding issues?
 
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For those mentioning fire concerns with lithium, that's more of a concern for Li-ion batteries. The stuff typically used in boats is LiFePO4, which is a very different chemistry. Energy density is lower than Li-ion (but still much higher than lead acid) and LiFePO4 doesn't have the big fire danger of a large Li-ion battery.
Since I'm now driving an all electric boat, I have spent countless hours researching all the various battery chemistries. The above comment on LifePO4 batteries is right on the money! Not to mention they are about half the weight of AGMs. Also, they don't have one drop of any kind of liquid and continually put out max power right down to fully discharged. Yes, they are expensive but when you consider the expected number of cycles a FLA or AGM will give you (200-300?) the LIFEPO4s will give you 2000-3000 before failing. More & more golf carts and electric vehicles are switching to LIFEPO4s.

Click on the link below and then scroll down to Lithium iron Phosphate (LIFEPO4) Probably the best article I've found on this subject.



https://ddmotorsystems.com/ElectricBoats.php
 
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