Realistic non-bs comparison of lithium to lead

[john61ct]

A GC House bank and an LFP one do exactly the same job.

LFP does it better but in the NA market the systems cost 7-10x more.

The DIY approach is fine IMO but takes more research time and a higher skillset than 99% of owners are willing to acquire.

If you don't want to spend those costs, just stick with lead and live within its limitations.

[john61ct]

Originally Posted by CatNewBee

Yellow top spiral cell AGM 75Ah are sold for a fortune in Europe 350$

And they aren't even suitable for true deep cycling.

Trojan T-105s are $110-160 in the US. How much there?

Deka GCs come out to $1 / AH @12V, I doubt anything else is better value worldwide.

[peter57]

Originally Posted by KTP

I went back and checked on stock of the Firefly batteries at Fisheries and I do see that the 4V@425AH L16 cells are in stock! $659 each.

(Some confusion here because in the picture printed on the cell it says 4V@450AH at the 20 hour rate but the literature says 4V@425AH at 20 hr rate)


Ok, so now consider this. 12 of those would be 48V @ 425AH (or 450AH?)

That is 16,320 Wh at the 20 hour rate and 80% DoD! That would be 48V at 21.25A going to the electric drive, or about 1kW, which I have some indication could push our displacement hull at 2.8 to 3 knots in calm water. This would give nearly a 60 nm range at very slow speeds. Alternatively, it is likely we could do 5 to 5.5 knots at 5kW to the motor, giving us probably a 12 to 15 mile range at a quite reasonable speed (again in calm water).

They are 94 pounds each, so not exactly featherweight and 12 of them would put us somewhat over the 700+ pounds of engine/tank/fuel that was removed, but we could discard the two existing house batteries and use a 48V to 12V DC-DC converter for lights + electronics which would be a negligible load on a 16,320 Wh bank. Thus really we would be only adding a couple hundred pounds to the boat over the former diesel engine and support equipment and have a honkin house battery when on the hook for several days.

Cost for 12@$659 would be $7908 plus 10% tax (bummer) vs Lifeline 16@$370=$5920 no tax (free shipping).

Lifeline expected life is 500 cycles at 80% DoD, probably more in the range of 200 cycles if abused and not fully recharged. The L16 from Firefly says an amazing 4900 cycles at 50% DoD and 1500 cycles at 80% DoD. This rivals lithium, with the only big downside being the weight. If only we could remove 2000 pounds of keel...

When your on the hook for a few days your batteries could be already be near flat just getting there.

How do you charge them to get back if there is no wind. A generator big enough to charge all those lifelines would be bigger than the motor your taking out plus the fuel tank or you are going back to the dock to charge, maybe in tow.

I have two 225 amp/h Lifelines, 150amp Balmar alt. MC 612 reg. and if they drop to 50% Dod you need to motor all day to bring them back to 95% no fun when the wind is good for sailing.

Very disappointed with AMGs never again, its back to Trogan 150's or go the whole mile and go lithium. $ ouch

We have a very sad story here of the same dream on a 42' boat , he is $60,000 in, with the generator, Lithium batteries and supposed state of the art electric motor and drive (which has already gone awry) . I have the same design boat and use less fuel. I was keen as when he started thought it was not a bad idea, luckily I did not have the money at the time.

Good luck.

[mainesail]

Through all the BS, in the end lead flooded cell batteries are still, by far, the best batteries for MOST applications. The problem is that they require a commitment to care that many sailors are unwilling to make-thus the opening for AGM etc.. That commitment requires an appropriately sized battery bank to meet to routine loads and charging equipment that will effectively and efficiently keep them in top condition. This means, usually, multiple sources of recharge energy and sophisticated charge management. In essence, typically keep discharges to no lower than to 70-75% charge and NEVER below 50%. Charging capability is required at bulk levels, finish levels and float-typically 3 step charging. Asking your auxiliary to do all that is super inefficient and bad for your engine, so solar, water and wind remain youradditional options. None of this is cheap, though not superbly expensive, but getting it right makes life easier and your electrical system happy.
For more sophisticated needs, I would call Bruce Schwab, of Ocean Planet energy-he advertises here.

A long time rigger, he competed in the Vendee Globe aboard Ocean Planet. I have sailed with him on her and he has long been way ahead of the curve about all things electrical and electronic. Now operating a business designing, developing, selling and servicing cutting edge boat energy systems, he is totally approachable and responsive to his customers.
Cheers, Will

[KTP]

Originally Posted by peter57

When your on the hook for a few days your batteries could be already be near flat just getting there.

How do you charge them to get back if there is no wind. A generator big enough to charge all those lifelines would be bigger than the motor your taking out plus the fuel tank or you are going back to the dock to charge, maybe in tow.

I have two 225 amp/h Lifelines, 150amp Balmar alt. MC 612 reg. and if they drop to 50% Dod you need to motor all day to bring them back to 95% no fun when the wind is good for sailing.

Very disappointed with AMGs never again, its back to Trogan 150's or go the whole mile and go lithium. $ ouch

We have a very sad story here of the same dream on a 42' boat , he is $60,000 in, with the generator, Lithium batteries and supposed state of the art electric motor and drive (which has already gone awry) . I have the same design boat and use less fuel. I was keen as when he started thought it was not a bad idea, luckily I did not have the money at the time.

Good luck.

I plan on having 1600 watts or more of quickly deployable solar, so if we are on the hook all day with no wind and some sun, it should get the batteries back to near full. If it is overcast it might take a few days.

These things are as complicated or simple as you want to make them. Sure you can spend $60,000 and have a system that doesn't meet your expectations. You can also spend $10,000 and go into it with the appropriate expectation (I will be able to enter/leave marinas and locks under electric motor power and I will have enough power to move the boat off of a dangerous spot to the point where I can raise the sails or set an anchor. I will not be able to race a hurricane or power up a channel against a 4 knot tide).

[ramblinrod]

Originally Posted by KTP

I am trying to decide between lithium batteries and lead acid batteries to power an electric drive in our 34 foot Pacific Seacraft sailboat. We have removed a 450 pound diesel engine + transmission, sea water strainer, Racor filter, exhaust riser, 70 pound diesel tank and 210 pounds of diesel fuel. Thus we have about 730 pounds to work with before exceeding the previous displacement of our craft. The new electric brushless motor plus control and reduction/mount will be less than 50 pounds, leaving about 680 pounds for batteries and wire.

I am inclined to start with eight Lifeline 12V AGM in 125AH capacity in a group 31 case. These will fit nicely in the port and starboard storage under the seats in the main cabin which is fairly low and balanced. At 74 pounds each, this would be 592 pounds, or about 90 pounds less than the old engine and fuel. At 48V nominal and 250AH, draining the batteries 50% at a 8 hour rate would yield 5,760Wh with a lab environment lifetime of 1000 cycles according to Lifeline data. Draining to 80% at the same 8 hour rate would yield 9,216Wh with a lab environment lifetime of approximately 500 cycles.

For initial use to enter and leave crowded marina and motor down channels to sailing waters, the 8 hour rate should be realistic and the batteries will be charged back to full after each cycle or within a day or two. Our plan also has quite a bit of solar spread around the boat, hopefully yielding 400 to 800 watts during peak sun from approximately 1600 watts of panels (assuming a lot of shading will prevent the system from ever really achieving the full rated output). Thus a day at anchor might yield something like 2kWh up to 6kWh back into the battery bank. There is also some potential for sailing regen with the electric motor/prop in strong winds but this will have to be tested and is not really expected to contribute much.

Eventually I would like to have a better battery solution than the AGM but I do not think we are quite there yet (it always seems a few years out, like landing on Mars). Companies have come and gone, BMS devices discontinued, very few tried and true off the shelf products that can be trusted to perform for years. Probably Torqeedo is the closest match with their 26V 2700 Wh waterproof, multiple protected packs for ~$2500 but these require individual chargers, special key switches, etc. They also claim only 900 cycles at 80% DoD and the batteries lose 4% a year capacity to age. At 80% DoD and a 8 hour rate, they would have likely double or better the lifetime of the Lifeline AGM but cost $10,000 vs $3000. Still, it is one of the better ideas for a safe, mostly off the shelf solution to get a 10kWh bank into the boat at half the weight of lead acid or better.

While we are on cycle life, it is probably important to point out that any claim of more than about 2000 cycles for a battery is silly, as the aging will come into play long before that amount of cycle life is reached. A typical full time cruiser would likely only be able to cycle 365 times per year and a weekender would most likely cycle about 50 to 100 times per year. Someone using their boat only during sailing season might only cycle 25 times per year.

Based on that, it could be that getting 200 cycles from a Lifeline battery at 80% DoD could yield as much as 8 years of life. Going for 2000 cycles from a lithium bank would take 80 years and the battery would be long dead from aging before that figure is reached. Also there is the factor of fresh batteries vs aged batteries. While a lithium bank might last 3 to 5 times as long as a AGM bank and cost 3x as much, the AGM will have full capacity at each replacement point while the lithium could be down 12% capacity at the first replacement point and 24% capacity at the next due to age. Plus there is the opportunity cost of the money used up in the initial investment, which is negligible in this low interest rate environment but might be significant down the road.

The weight and size are the big factors and probably the one reason I am still considering lithium even with the extra cost. Weight wise, I could probably get 20kWh to 30kWh for the same displacement as 10kWh of the lead acid.

The PS34 is a wonderful cruising vessel.

The average person owns a particular boat for 6 years.

If I was shopping for one, and came across 2 examples in equal condition, one with a good condition 3 cylinder diesel, and one with electric propulsion, I would deduct $25K from my offer for the one with the electric drive.

(This is about what it would cost to rip out the electric drive and install a new diesel (if I couldn't find a decent used one in my time frame), including value of my time at regular rate.)

Some may be interested in electric propulsion, but I think the actual prospects will be relatively limited, and you will devalue the boat at great expense, by this conversion.

Consider that a cruising vessel diesel, well maintained will typically last longer than the current owner (~20 years +/-).

The expensive batteries in an electrically propelled cruising vessel won't. (Average 5, if taken very good care of.)

If resale value (or target market size) doesn't matter to you, and you don't mind low speed and limited range, especially when in the calm before an approaching whirly girl, go for it.

For a day sailer, electric propulsion is viable to get one in and out of harbour before connecting to shore power every night. For a cruisier, may be a consideration for some, but not for me.

A PS34 is a great cruiser; I suspect few would chose one for a day sailer.

[KTP]

Originally Posted by ramblinrod

The PS34 is a wonderful cruising vessel.

The average person owns a particular boat for 6 years.

If I was shopping for one, and came across 2 examples in equal condition, one with a good condition 3 cylinder diesel, and one with electric propulsion, I would deduct $25K from my offer for the one with the electric drive.

(This is about what it would cost to rip out the electric drive and install a new diesel (if I couldn't find a decent used one in my time frame), including value of my time at regular rate.)

I already deducted the $25K when I purchased the boat as I was placing little value in the 28 year old Yanmar which had been poorly maintained. Pulling the engine was also necessary to access the steering quadrant/stuffing box which had also been poorly maintained and had been gurgling up salt water for years. The aluminum quadrant snapped in pieces when I was taking it off and the stainless steel steering cable was frayed 3/4 of the way through near the quadrant. None of this would I have been able to access with the engine in the way (I am 6'7"). Now with no oversized engine for that tiny space, I can get back in there with my head right at the rudder shaft and inspect/repair everything. That alone makes the boat worth more to me than it was with the old engine (which upon pulling out was shown to have more potential problems including external oil lines with severe corrosion, shifter cable linkages that fell apart, and at least one impeller which was starting to disintegrate).

What would you rather have on the open ocean? A PS34 with electric motor and a new steering quadrant/cables with access to the same or a PS34 with a 28 year old diesel engine on the edge of failure and a quadrant you can break in half with your hands? I think I have improved the value of the boat.

Edit: Oh, and I have not even touched the 28 year old aluminum diesel tank of unknown condition but an item which has been known to have problems after shorter time periods than that. Electric motor has no need of that tank, so no headache there either.

[ramblinrod]

Originally Posted by KTP

What would you rather have on the open ocean? A PS34 with electric motor and a new steering quadrant/cables with access to the same or a PS34 with a 28 year old diesel engine on the edge of failure and a quadrant you can break in half with your hands? I think I have improved the value of the boat.

Those aren't the only 2 choices.

Having devalued the boat due to the poor condition engine, you could have:

1. Re and Re the engine, rebuild, addressing the maintenance neglect in the mean time. (This would have eliminated the devalue from average).

2. Re and Re the engine with a good used (replace with same). (This would have eliminated the devalue from average).

3. Re and Re the engine with new diesel. This would have increased value about 80% of parts cost, depreciating by 5% per year for 15 years, then no change in value from average.)

4. Re and Re the engine with electric propulsion. Considerable expense while not really increasing value (for many prospects) much over the hull with no engine at all (as they would want it removed to have a proper diesel installed).

If you have already considered this, and made this choice to go electric anyway, that is absolutely fine and your business; it is your boat.

But for others who may be contemplating jumping on the electric propulsion band wagon, please consider this. Sailing UMA (youtube channel) gutted an engine to put in electric. They have had their share of issues. They have a huge anchor so if a hurricane comes they can hopefully ride it out. Often, they are driving the boat into harbour by lashing their outboard powered dinghy to the side of the boat. For some reason they decided to go chain drive vs direct drive. The chain drive was surprising noisy. They had a battery failure, that I suspect was due to a high impedance connection that high load propulsion drives can turn into a fire in a heart beat.

It's OK, to adopt new or alternate tech; just don't be blinded by the PROs and oblivious to the CONs.

If a prospective customer of mine, requested an electric propulsion conversion, I would have this candid conversation with them, and then if they wished to proceed, would gladly design and install the system for them.

My fear is that some may find someone on the internet bestowing the PROs and disregarding the CONs in order to convince them it is the right thing to do for them.

For the vast majority of cruisers (like 99.5%), I think electric propulsion would be a huge mistake.

[skipmac]

Hi Will,

On a couple of your points I have a slightly different take.

Originally Posted by mainesail

Through all the BS, in the end lead flooded cell batteries are still, by far, the best batteries for MOST applications.

On this I 100% agree.

The problem is that they require a commitment to care that many sailors are unwilling to make-thus the opening for AGM etc..

This is where I have a different opinion, especially comparing FLA to AGM batteries. As far as charging routines, AGMs from all my research and based on testing and data from industry experts, are much
more demanding of a specific charging regimen and less tolerant of deviation from what they need than FLA batteries. The big one, AGMs need to be fully charged on a regular basis to avoid damage and early demise. FLA batteries prefer the same but are much more tolerant of partial SOC. AGMs don't require constant checking of water levels but in my experience that hasn't been a big issue with my FLA batteries.

That commitment requires an appropriately sized battery bank to meet to routine loads and charging equipment that will effectively and efficiently keep them in top condition. This means, usually, multiple sources of recharge energy and sophisticated charge management. In essence, typically keep discharges to no lower than to 70-75% charge and NEVER below 50%. Charging capability is required at bulk levels, finish levels and float-typically 3 step charging. Asking your auxiliary to do all that is super inefficient and bad for your engine, so solar, water and wind remain youradditional options. None of this is cheap, though not superbly expensive, but getting it right makes life easier and your electrical system happy.
For more sophisticated needs, I would call Bruce Schwab, of Ocean Planet energy-he advertises here.

Thanks for the recommendation. I'll certainly check out his business.

A long time rigger, he competed in the Vendee Globe aboard Ocean Planet. I have sailed with him on her and he has long been way ahead of the curve about all things electrical and electronic. Now operating a business designing, developing, selling and servicing cutting edge boat energy systems, he is totally approachable and responsive to his customers.
Cheers, Will

[KTP]

Originally Posted by ramblinrod

They had a battery failure, that I suspect was due to a high impedance connection that high load propulsion drives can turn into a fire in a heart beat.

This is just a failure of the installer and possibly improper maintenance or ignorance of the owner. Quite a few cruisers out there are running with fairly big battery banks and using things like microwaves, air conditioners, water makers which combined can cause a high impedance poor connection to heat up. It doesn't have to be an electric propulsion drive that causes this.

We built our own RV and have a 4kW inverter in that. I used marine wire, proper breakers disconnects and fuses, and I check the torque of the high current connections at least once every few months with a digital torque wrench. We run our A/C off of solar + battery and are routinely drawing 50 to 100 amps through the connections. Another neat gadget that is coming down in price is a FLIR camera which can quickly spot a high impedance connection under while under load and would make it a snap to double check things more often.

Again, I have to ask how the people who scull manage to move out from a hurricane?

[ramblinrod]

Originally Posted by KTP

This is just a failure of the installer and possibly improper maintenance or ignorance of the owner.

Agreed. However, things require maintenance, and stuff can happen if the maintenance is not done soon enough.

Quite a few cruisers out there are running with fairly big battery banks and using things like microwaves, air conditioners, water makers which combined can cause a high impedance poor connection to heat up. It doesn't have to be an electric propulsion drive that causes this.

Correct, but if the microwave goes down, all is not lost. A reliable propulsion system is of great importance. Of all the boats out there, few maintain a 1200 W DC load for greater than a minute or two.

When one gets into an electric propulsion system, that pretty much mandates high loads for lengthy periods. Great risk of failure. Higher consequence of failure. Necessitates high level of preventative maintenance that most boaters (in my experience) don't tend to practice.

We built our own RV and have a 4kW inverter in that. I used marine wire, proper breakers disconnects and fuses, and I check the torque of the high current connections at least once every few months with a digital torque wrench. We run our A/C off of solar + battery and are routinely drawing 50 to 100 amps through the connections. Another neat gadget that is coming down in price is a FLIR camera which can quickly spot a high impedance connection under while under load and would make it a snap to double check things more often.

OK, this is explaining a lot. You like to tinker with electrical stuff. Good on ya. If you actually do perform the maintenance described, better on ya. 99.8% don't.


900W average continuous? In 24 hours that is 21.6 kW-hrs

To have 2 days of usable FLA battery capacity from full charge without charge source, that is almost 2000 A-hrs capacity at 48 Vdc.

That is one MF big bank on a PS34.

To replenish that load drawn in one solar day would require 8.6 kW of solar, properly aimed at the sun and unshaded.

That is one MF big array on a PS34.

Again, I have to ask how the people who scull manage to move out from a hurricane

?

They don't; and their boat will be devalued about $25K because they don't have an engine that 99.8% of prospective buyers want (unless maybe the boat belonged to Lyn and Larry, and then I'm still not so sure).

Again, your boat, your decision, but trying to convince me (or yourself) that it won't devalue the boat at resale time with this kind of logic is not likely to prove fruitful nor valid.

[KTP]

Well ok if all we are talking about is devaluing at resale time then I guess there is no issue. We are at the point where we have no motor in the boat already. We have the old Yanmar undamaged that we pulled out and it is in storage. It would IMO need a rebuild to be reliable but I would never completely trust that since I don't trust mechanics all that much (they work under a time clock). They might reuse some part because it is "good enough" and inevitably that turns out to be the part the fails. Also this 3HM35F is likely fairly expensive to rebuild...I would bet 10k at least around here.

Anyway, in the boating world, $25k is peanuts. Just the new quadrant and chain/cables is nearly $1000 from Edson. Thank goodness we don't need a new pedestal and compass...they are like $4 grand.

Guess that is why a new PS34 sells for $380k

[ramblinrod]

Originally Posted by KTP

Well ok if all we are talking about is devaluing at resale time then I guess there is no issue. We are at the point where we have no motor in the boat already. We have the old Yanmar undamaged that we pulled out and it is in storage. It would IMO need a rebuild to be reliable but I would never completely trust that since I don't trust mechanics all that much (they work under a time clock). They might reuse some part because it is "good enough" and inevitably that turns out to be the part the fails. Also this 3HM35F is likely fairly expensive to rebuild...I would bet 10k at least around here.

Anyway, in the boating world, $25k is peanuts. Just the new quadrant and chain/cables is nearly $1000 from Edson. Thank goodness we don't need a new pedestal and compass...they are like $4 grand.

Guess that is why a new PS34 sells for $380k

Unless you are bound and bent to have an electric drive no matter what, I recommend you talk to other boaters in your area who have had engines rebuilt locally and had no issues.

This can be done for less, you will not have the speed / range limit issues, and will not devalue the boat.

It could be that you are just a lot more comfy with electrical thingies than mechanical thingies and I get that, but there are very few things on this planet more reliable than a tried and true marine diesel engine that has not been abused.

If it has been abused, a rebuild will solve any internal issues. If it is not a candidate for rebuild, you will be told very early.

It is true that infernal combustion engines require maintenance and occasionally break down. (So do electric motors and battery banks.)

With a rebuild, you have two choices with respect to peripherals and maintenance items that were not replaced during the rebuild: (lift pump, high pressure pump, fresh water pump, seawater pump, thermostat, alternator, starter etc.)

a) Leave all as is and repair as they break. This will put you in the same position as if the original engine was old but well cared for.

b) Replace all now and keep original as known fitting and working spares.
This will put you in the next best thing to a new engine at about 40% of the cost, about equal to your electric drive that will have huge maintenance costs (battery replacement) about every 4-6 years, depending on use and abuse.

[john61ct]

I don't know anyone doing EP for financial/practical reasons.

Usually stems from green ideals, and willing to pay lots more and lose a certain amount of practical functionality towards that end.

Often not quite realizing just how much.

[GrowleyMonster]

Originally Posted by john61ct

I don't know anyone doing EP for financial/practical reasons.

Usually stems from green ideals, and willing to pay lots more and lose a certain amount of practical functionality towards that end.

Often not quite realizing just how much.

I did. I needed to replace the aging Atomic and did not want to replace it with an aging diesel or aged diesel. I saw that I could go electric for about 1/3 the cost of a new diesel and I did. A $2000 boat doesn't to me call for an $8k engine. So yeah, basically financial reasons. I didn't really fall in love with electric until I had mine going and really started tinkering with it.