Batteries - What The Future Holds.......

Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
Somewhere over the horizon Lithium battery technology, namely, LiFePO4 or a similar inherently safe variant, will come to cruising boats.

This thread is about LiFePO4 technology not any other Li technology. LiFePO4 is a very safe Li technology but is not yet a "drop in" replacement for LA batteries.

I say that, but the reality is LiFePO4 already here. The cost for pre-made factory packs however keeps the "average Joe sailor" away from it currently... I am installing Genasun LiFePO4 batteries next week that are in the 24k range for the entire bank and system..

IMHO this technology is NOT yet ready for "drop in" or DIY level installations. It will eventually trickle down but is not ready for DIY prime time just yet..


Genasun, Mastervolt and Victron are all in the Li arena with good offerings for marine installations but it is very early in the technology and still quite expensive for factory made..

I physically built and engineered my own LFP battery pack but this level of build is a long way from DIY level. I would not advise folks to try and undertake this on their own without a vast knowledge of the technology.

This morning, after a number of testing cycles, I am load testing the bank. The bank is 400Ah made up of four Winston 3.2V 400Ah cells in series.

One amazing thing about this technology is there is virtually no Peukert effect. The Peukert is about 1.03..... The picture below shows the pack supplying a 100A load after a full hour of doing so. The pack voltage is still 12.85V !!!!!!!! :D

The big benefit to me with LiFePO4 is that there is virtually no acceptance limiting. You charge back to 98% - 100% with ease, if you have the current. This bank could be charged at 3C or 1200A if one had the capability. Once it starts limiting current it does so only for about 20-25 minutes and this is with a .35 C charge current....

With lead acid batteries you can only cycle to 50% SOC or you risk a drastic reduction in cycle life. You can also only ever re-charge, when off cruising, to about 80% SOC due to acceptance and current limiting.

This means the usable capacity of the bank is about 30-35%. You are hauling around 65% of your batteries that are virtually unusable. With LiFePO4 you are only hauling around 20% that you don't use and 80% of the capacity you paid for you can actually use.. Even at 80% DOD they still claim 3000 cycles.

Do I believe this? No, not entirely. Hell Lifeline claims 1000 cycles to 50% DOD on their AGM's yet I see them dead with 100-300 "real world" cycles on a regular basis. Real world and "lab coat" world are usually vastly different. But still guys in the EV world are claiming these cells are actually doing this. I will play the "wait & see"...

The technology is complex, different and requires a battery management system to keep from over charging the cells and discharging to deeply. It requires individual cell level monitoring. The BMS also ensures that no cell can exceed the safe voltage.

These batteries literally charge until full then "hockey stick"/spike in voltage if you don't control the voltage well. This means the voltage rises VERY quickly at the end and can over shoot the safe level and destroy a cell in the process.

My boat systems will need to be modified. I need to have a charge bus and a load bus both controlled and monitored by contactors/relays. The load bus will disconnect the load away if a any cell hits the low voltage threshold. My solar, battery charger and alternator will also all be controlled by their own high voltage cut relays to prevent any cell from going over voltage. Because of the immense energy stored in these batteries the fuse for them is Class T at a bare minimum. I measured the bank last night at over 5200 cranking amps!!!!!:eek: The short circuit capability of this bank could potentially explode an ANL fuse.....

This 400Ah bank is also smaller and 76 pounds lighter than our group 31 375Ah flooded bank.. It is also rated for 3000 cycles to 80% depth of discharge (believe that when I see it). I will cycle to 50% - 60% DOD and that puts me over 5000 "rated" cycles (believe that when I see it too)...

This is what the future of batteries on boats may look like... Darn bank is heating my garage right now......! I just checked and at 170Ah's removed from a 400Ah rated battery pack, at a 102-105A constant load, the pack voltage is still 12.79V!!!!!)...
 
Jan 30, 2012
1,123
Nor'Sea 27 "Kiwanda" Portland/ Anacortes
This is very cool stuff.

As to DIY one would expect the engineeers at Boeing would have got the charging system designed to absolutely protect from overcharge=>overheat voltage appplied to LI batteries in the 787. Evidently things were not completely thought through despite the efforts of some of the best talent on the planet.

Do the designs and componenets you are using absolutely protect from these type risks?

Charles
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
This is very cool stuff.

As to DIY one would expect the engineeers at Boeing would have got the charging system designed to absolutely protect from overcharge=>overheat voltage appplied to LI batteries in the 787. Evidently things were not completely thought through despite the efforts of some of the best talent on the planet.

Do the designs and componenets you are using absolutely protect from these type risks?

Charles
LiFePO4 / Lithium Iron Phosphate (LFP) is a totally different technology than LiCoO2 / Lithium Cobalt Oxide (LCO). The "Li" part is the only thing the same. LCO technology is more energy dense but also a lot more unstable than LFP...

So far I don't know of or have read of any LFP cells catching fire from such things as dead short circuiting or over charging.. There are actually a number of tests done which included short circuiting LiFePO4 cells and they did not explode or catch fire they got warmer and discharged.....

Some home made BMS systems "reportedly" caught/caused fires but I've not seen proof it was caused by the batteries.. Lots of people have over charged LiPO4 batteries and had them bulge and split open but no fires that I have read about. They usually "smoke". In a fire, one already burning, they will accelerate and cells may pop but you'd need to already have your boat burning at that point..

LiFePO4 is one of the most stable & safe of the Li technologies. Is any battery 100% safe, absolutely NOT.... Not lead acid not Li not NiCad not NiMh.... Many argue LiFePO4 is actually safer than LA technology but for me I treat all batteries with respect..
 
Apr 18, 2007
53
Jeanneau Sun Oddysey 40.3 Chicago, IL, USA
This is very cool stuff. One inevitable result of this will be electric motors replacing diesel and charging with renewable sources (like you already use).

I will also mention that for others wanting to experiment with this at a smaller scale that most of this technology is commonly used by radio control models like airplanes, helicopters, and cars/trucks with LiPo and LiFe cells. While I wouldn't ever classify this as 'safe' you can learn alot and replace some other battery usage without breaking the bank or taking excessive risk.

I'll be looking forward to hearing how this turns out for you Maine Sail.
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
I shot this video at the tail end of capacity testing this bank. The long and short is this is a 400Ah pack and I drew 425Ah's out of it before shutting down the test. The cell voltages were still well within in the safe zone.

Remember that in this video this 400Ah bank has been subjected to a 100A+ load for over 4 hours and the voltage was still just a tad below 12V when 425Ah's had been removed..

I've never seen a battery perform like this and never thought it would be possible...

 
Sep 15, 2009
6,243
S2 9.2a Fairhope Al
how much would a set of theses cost on average and what is the foot print of the bank if you will .........

regards

woody

ps ...this is great news on a 50amp day draw that would mean you could go for 8 days with no charge or restocking the batts....
 
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May 27, 2012
1,152
Oday 222 Beaver Lake, Arkansas
I dont know. Boeing just had their new Dreamliner grounded, worldwide, because of lithium batteries catching fire. Cell phones catch fire with the same batteries. If my phone catches fire I can throw it. If I had a lithium battery in a car I could slam on the brakes and bail out, or throw my kid or wife out. If a plane catches fire at 35,000 feet over the ocean, its likely to end very, very badly. A sailboat far from shore could be in peril real fast with a burning battery. And from what ive read, a lithium battery can burn real hot.

Lead acids may be inferior from a physical watt hour per pound per cu/ft perspective, compared to some of the new technology. But I would take a dead battery, over a burning battery, any day. Lead acids dont burn. They might blow their tops off, blow some acid, make a big mess, maybe set the cables on fire, but the batteries arent really that dangerous, and quick chop with a hatchet can generally stop the fun.

Whats the best guess Boeing will do to fix their problem? I bet they resort to lead acids, at least in the short term.
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
I dont know. Boeing just had their new Dreamliner grounded, worldwide, because of lithium batteries catching fire. Cell phones catch fire with the same batteries. If my phone catches fire I can throw it. If I had a lithium battery in a car I could slam on the brakes and bail out, or throw my kid or wife out. If a plane catches fire at 35,000 feet over the ocean, its likely to end very, very badly. A sailboat far from shore could be in peril real fast with a burning battery. And from what ive read, a lithium battery can burn real hot.

Lead acids may be inferior from a physical watt hour per pound per cu/ft perspective, compared to some of the new technology. But I would take a dead battery, over a burning battery, any day. Lead acids dont burn. They might blow their tops off, blow some acid, make a big mess, maybe set the cables on fire, but the batteries arent really that dangerous, and quick chop with a hatchet can generally stop the fun.

Whats the best guess Boeing will do to fix their problem? I bet they resort to lead acids, at least in the short term.
Read post #3, not the same Li technology...
 
Apr 29, 2011
134
Finnsailer 38 Massachusetts
Don't LiFePO4 batteries suffer from irreversible capacity loss if you operate them below 0 degrees celsius? I suppose most of us don't use our boats at that temperature, but it would mean taking the batteries off the boat every winter.
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
Don't LiFePO4 batteries suffer from irreversible capacity loss if you operate them below 0 degrees celsius? I suppose most of us don't use our boats at that temperature, but it would mean taking the batteries off the boat every winter.
The operating range of the Winston cells is -45C or -49F to +85C or 185F....
 
May 27, 2012
1,152
Oday 222 Beaver Lake, Arkansas
From all I have read, all Lithium batteries are prone to thermal runaway. The Dreamliner may have had Lithium Cobalts, and these are Lithium Iron, but Lithium Iron, or any lithium based battery, is not something I would want to deal with far from shore should it decide its no longer happy. Not today anyway.

For me, I will wait and see. I am pretty sure Boeing had the best and brightest engineers, and the best quality put into their batteries, far better than anything consumer grade, and they failed, and thankfully without loss of life. I will be watching to see how they fix the problem, but I would be surprised if they try anything Lithium based again.
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
From all I have read, all Lithium batteries are prone to thermal runaway. The Dreamliner may have had Lithium Cobalts, and these are Lithium Iron, but Lithium Iron, or any lithium based battery, is not something I would want to deal with far from shore should it decide its no longer happy. Not today anyway.

For me, I will wait and see. I am pretty sure Boeing had the best and brightest engineers, and the best quality put into their batteries, far better than anything consumer grade, and they failed, and thankfully without loss of life. I will be watching to see how they fix the problem, but I would be surprised if they try anything Lithium based again.
Your post is exactly why DIY level installations are not ready for prime time. I stated this in the first post. The future will come but right now the only option is a factory built system for the DIY level and they are very expensive..

Planes today are using Li technology as are computers, cell phones, cordless tools, wheel chairs, cars, trucks, buses, fork trucks, industrial machines etc. etc. etc..... We are surrounded by Li battery technology..
 
Sep 15, 2009
6,243
S2 9.2a Fairhope Al
how much would a set of theses cost on average and what is the foot print of the bank if you will .........

regards

woody

ps ...this is great news on a 50amp day draw that would mean you could go for 8 days with no charge or restocking the batts....
i see why you didn't answer my question after looking up theses battries.....holy c*#^ theses things cost more than my boat is so making the foot print irrelevant:eek:......

regards
'
woody

r
 
Apr 29, 2011
134
Finnsailer 38 Massachusetts
It is interesting that the Winston cells claim such a wide temperature range because some sources indicate that LiFePO4 batteries are not to be used below 0 celsius. They must have come up with some better chemistry. I imagine the car market is providing lots of bucks for battery research, and obviously low temperature operation is critical in that market. I know that GE just built a new research factory near here for their new Durathon batteries, which use sodium nickel chemistry. Of course, they claim all sorts of efficiencies and superiority over other battery types. I suspect we're just seeing the tip of the iceberg in new battery tech.
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
i see why you didn't answer my question after looking up theses battries.....holy c*#^ theses things cost more than my boat is so making the foot print irrelevant:eek:......

regards
'
woody

r
Yes today they are very expensive but that will change. My pack will cost about the same as a premium AGM bank of the same Ah capacity but that EXCLUDES my time & labor which is quite extensive when building your own pack.

The initial cell balancing requires a bench top power supply with adjustable voltage and current and these are not inexpensive. The initial balancing and cycling and testing has already taken about 8-10 hours of time. They are now balanced and have been cycled to 50% DOD 7 times and the balance is within 0.01V on each cell.. My BMS will only be used as a "fail safe" and not relied upon for cell protection on a regular basis. The design and charging parameters I have set up keep the cells well within the safe range.

Again this is a ways from DIY and pre-made packs from Genasun, Mastervolt or Victron are still quite expensive. The bank I am flying to Puerto Rico to install today through Thursday cost about 24k for a 70 footer, excluding labor, but at the cycle design the bank should have 4000 - 5000 cycles.............
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
It is interesting that the Winston cells claim such a wide temperature range because some sources indicate that LiFePO4 batteries are not to be used below 0 celsius. They must have come up with some better chemistry. I imagine the car market is providing lots of bucks for battery research, and obviously low temperature operation is critical in that market. I know that GE just built a new research factory near here for some sort of new battery tech. they are working on. I'll have to look into what they are doing there.
They added Yttrium to the cells to help them deal with lower temps. They lose usable capacity, like any battery, when cold but most sailors are not "using them" in those temps so capacity is a non issue because when it warms back up they capacity is there.

That said my pack will come off winters for top balancing. The individual cells weigh about 30 pounds each so they are simple and light to remove..
 
Jan 4, 2010
1,037
Farr 30 San Francisco
Look at electric vehicle forums for experience with Winston/Thundersky batteries.
Balancing at all times is important
 
Jan 4, 2010
1,037
Farr 30 San Francisco
House bank is a really good application, charge rates are modest even with the biggest alternator compared to the capability of the cells, and discharge rates are tiny.

The cost isn't so bad if, you replace usable capacity for usable capacity. 400aHr lead acid has 200aHr usable can be replaced by 240Ahr lithium and with 2k charge discharge cycles your cost per cycle isn't so bad.

Also Li can be left in a intermediate charged state for any time so you don't have to fully charge it as you do with lead acid, and charge acceptance is far higher so charging will require much less engine time and diesel which could be a factor in the boonies.
 
Feb 6, 1998
11,667
Canadian Sailcraft 36T Casco Bay, ME
House bank is a really good application, charge rates are modest even with the biggest alternator compared to the capability of the cells, and discharge rates are tiny.
Yes the max charge rate of these prismatic cells is 3C or 1200A for a 400AH bank but the ideal charge rate is 0.3C.. A sailboat can not generate anywhere near a 3C current current so heat is a non issue during charging. You still want to stay out of the upper charge knee, but that is pretty easy to do..

The cost isn't so bad if, you replace usable capacity for usable capacity. 400aHr lead acid has 200aHr usable can be replaced by 240Ahr lithium and with 2k charge discharge cycles your cost per cycle isn't so bad.
But the cost gets even better when you consider the true capacity of an LA battery is 30-35%, once you are more than a day away from a dock.

With LA batteries declining acceptance makes it very, very difficult for sailboats to ever get back above 80-85% SOC and when you are only discharging to 50% SOC that gives you a real usable capacity of just 30-35%.. LiFePO4 will charge up into the high 90's before current limiting happens, and when it does, it happens fast.....

Also Li can be left in a intermediate charged state for any time so you don't have to fully charge it as you do with lead acid, and charge acceptance is far higher so charging will require much less engine time and diesel which could be a factor in the boonies.
Exactly, no need to get back to 100% SOC, no sulfation, essentially no Peukert effect and no charge efficiency hit. Take 100Ah out of of a LA batt and you're putting back 110-120% of that over 8-16 hours, to get to 100%, regardless of charge capacity. With LiFePO4 take out 100Ah's you put back 100Ah's and it is full. 100Ah's could be replaced in as little as 15 minutes if you had the current available to hit 3C... On our boat I will be able to replace 100Ah's in about 40 minutes and get back to 100%..

Very cool technology but unless you have deep pockets right now not really ready for a DIY install.

I am on my way to Puerto Rico (at JFK right now) to install a Genasun 24v and 12V LiFePO4 system on a 70 footer.

I have been on the EV forums for a while, almost two years. Lots of great info over there...