Lithium Ion Batteries

I went to a local boat show today and there was a booth promoting Lithium Ion Batteries for boat use. According to the guy in the booth, I could replace my single starting battery and four house batteries (AGM) with just two Lithium Ion Batteries (at a cost of $1,300 each) and save lots of weight.

He gave me a brochure that seems to disagree with what he said. The Lithium Ion Batteries are only 100 AH capacity so to duplicate the house bank I have now, I would still need four. That's 5 X $1,300!

The brochure compares their batteries with lead acid and claims that for each battery I will save $2,436 over a ten year period over lead acid batteries. Checking the brochure, I see that they figure I would need to replace each lead acid battery eleven times over a ten year period! That has not been my experience.

I'm going to pass on this for now.

Don't you love a good salesman?

Let's see . . . my flooded acid batteries are 1300's, cost $173 each and last 10 years on average. 5 x $173 = ???. . awe never mind !!

There is a huge thread on these batteries over on CruisersForum and it gets incredibly complicated. There is nothing about these batteries and their management that is simple. Yes, you can get incredible amp hours out of them and vastly superior discharge cycles and life cycles but understanding is beyond the average boater.

Check out the link you will be amazed at the complexity.

They got me going too: no maintenance, discharge down to 5%, full charge rate to 98%, double the amp hours, for example 100amps = 200 lead-acid amps, standard (gel cell) charger. You don't need as many because you can discharge em so low. I just couldn't justify 3x the cost.

Xsbank said:

They got me going too: no maintenance, discharge down to 5%, full charge rate to 98%, double the amp hours, for example 100amps = 200 lead-acid amps, standard (gel cell) charger. You don't need as many because you can discharge em so low. I just couldn't justify 3x the cost.

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Interesting math...

-Chris

I don' think it's math, I think it's philosophy.

I see that they figure I would need to replace each lead acid battery eleven times over a ten year period! That has not been my experience.

Figures dont Lie ,

But Liars figure,

ANON

There was also one of the hybrid cruisers on display (by a different vendor) but I didn't look at it. It was one of the "Do Not Board without broker" boats.

I did see the Ranger Tug 31 and checked it out but they had the flybridge closed off. interestingly, it's listed as LOA 31', LOA with swim platform 35'. I thought LOA was the length including swim platforms and anchor pulpits.

It's a nice boat and with a big enough truck and overwide permits you can trailer it but it's close to $400K.

WesK said:

I did see the Ranger Tug 31 and checked it out but they had the flybridge closed off. interestingly, it's listed as LOA 31', LOA with swim platform 35'. I thought LOA was the length including swim platforms and anchor pulpits.

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I think that is a cleaver way of saying that the swim platform is an option and part of the base length or price

eseyoung said:

I think that is a cleaver way of saying that the swim platform is an option and part of the base length or price

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According to the website, the swim platform is standard.

If the swim platform or bow pulpit is molded in it is part of the LOA. If it is bolted on it is listed as LOA plus the appurtenance.

Either way you will be paying for the molded LOA or the LOA + bow pulpit + swim platform, so it is a useful number to have.

The lithium guys say that you only need half the amperage rating because the batteries can be discharged to 5%. They have an automatic cutout. Lead acid can only be discharged below 50% at your peril. Also, lithium can be recharged up to 3000 times vs 300 for lead. You only need half the size of a lead bank. They don't need boxes, are better for solar etc etc.

Scoff all you want, they are our future. I have lead acid but if I wasn't distracted by all the other costs on my boat I'd have lithium. The only downside is the cost. Like led light bulbs, which are still too expensive for a house and the makers are still searching for a standard size and brightness. Both will come down eventually and we'll all have 'em.

I wonder if the lithiums are just a group of laptop batteries in a series/parallel setup. That's what some of the electric cars are doing, but it takes a lot of them since they are only 4-5 amp hours each. The other thing to remember about lithiums is the same lesson Boeing learned on the 787 and some people learned on laptops. Charging requires the proper control and monitoring or bad things happen.

Tom

Ideal batteries for the 24V rapid charge of a 12V battery bank in series parallel ala the charging at anchor thread.

Xsbank said:

............ Scoff all you want, they are our future. I have lead acid but if I wasn't distracted by all the other costs on my boat I'd have lithium. The only downside is the cost. Like led light bulbs, which are still too expensive for a house and the makers are still searching for a standard size and brightness. Both will come down eventually and we'll all have 'em.

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No doubt they are the future, but at least in my case, the future isn't here yet. Those batteries are $1,300 each. My AGMs are $280 each. I have five. And the Lithium Ion batteries are unproven in recreational boat use (They are great in power tools but that's a different application.)

Remember, the "leading edge" is often the "bleeding edge"! I'll wait a few years and see how they shake out in price and operation.

They have an automatic cutout.

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Yes, in the tools they do. Your drill or saw doesn't slow down, it just stops. Unnerving until you understand it.

I think I'll wait for Boeing to sort out the problems first!!

Have a friend who's building the replacement very heavy stainless steel battery containment vaults for the 787's. Boeing and the battery manufacture still haven't pinpointed the cause. But they're not finding any problems with the chargers. They're back to looking at the battery supplier for a manufacturing defect which may have caused an internal short.

Which has been a concern with Lithium Ion batteries in other applications as well. Contamination during assembly or something as small as a pinhole in the thin plastic membrane between cells can cause a thermal run-away, which cascades from cell to cell. In that state the battery vents "flaming gas" until the battery melts down.

That's a whole lot of trouble for a 60 lb battery that's no bigger than two car batteries. They had another 787 battery problem about a week ago. Maintenance found fumes venting from one cell in a battery pack.

AS the gov subsidizes more and more battery cars , eventually their batts will be shot.

Replacement is many thousands , so batt re assembler shops will spring to life.

The alt energy folks have been pulling apart the batt packs and tossing the dead cells and reassembling for quite a while.

When this becomes common there is a chance that LI will be common on the few boats that can use the tech.

Big advantage is very rapid charge ability at high amps.

Expensive to create a heavy charging system , so I think most folks will still simply grind away with noisemakers doing the 50% soc to 85% soc as they currently do.