Lithium Batteries (for the rest of us)

[sailorboy1]

I did read it, but am looking for useful advantages.

Lighter and smaller are of no interest to me. I already have the space for batteries and they aren't taking enough space that "saving" 2 square feet matter in a location not all that useful for something else. And saving 50-100 lbs on a 43' boat isn't of concern (I don't see how 100 lbs of anything could "clearly" rule out anything on cruising boat).

I'm rooting for you people who decide to spend the extra cash, but I'm still not seeing a return on investment.

[ebaugh]

Originally Posted by Maine Sail

I was talking in the opposite spectrum. A coast cruiser does not "wear out" FLA batteries via "cycles" they KILL them from bad practices. I see two to three year old dead banks with well under 100 true cycles on them on a near daily basis..

My point was/is if you can't take care of FLA batts enough to get 7-10 years of "seasonal coastal cruising" then you are likely going to destroy Li batteries too. My point is to work on your battery management practices & get them dialed in before you plunk down big cake/$$$ on Li.......

If you actually wear out FLA batts due to cycles then Li is a great fit.... This is why I specifically mentioned "seasonal coastal cruising"...

Honestly I replace sooooo many batteries with less than 100 cycles on them that it is not even funny.. When those customers ask "what batteries should I buy?".. The answer is the cheapest you can possibly find because you're just going to kill them anyway...

I've got one guy with a 34 footer who runs a single group 27 and has refrigeration. Can't talk him into anything but. He's on his third fridge compressor but "knows" it's not from the chronic low voltage he's feeding it... He gets one season out of a battery and accepts that and thinks it is normal. Forget getting back to 80% he's lucky to get back to 60% SOC.... he'd be a bad candidate for Li....

I don't know hardly anything about boating in you're part of the world, but I have done a few coastal flights from Boston to Baaa Haabah via the scenic low route. What I saw was lots and lots of little harbors and few marinas. Looks like many keep their boats on a mooring for the season?

I agree that the guy that kills his LA in a season is a poor candidate, but maybe a carefully engineered solar system for someone wanting to keep the fridge running all season to have a cold beer handy anytime they popped out to the boat might be a candidate? You could get almost twice the run time to cover cloudy days in the same space (and far less weight). Although, those would be expensive beers! I'd probably just stop at 7-11. But some might be willing to pay?

[skipmac]

Originally Posted by Don L

I'm rooting for you people who decide to spend the extra cash, but I'm still not seeing a return on investment.

Well same here. Methinks the LiFePO batteriies are just not quite ready for prime time. Long ago and far away I was an EE and even with that background the care and feeding of LiFePO batteries seems like a lot of hassle and lot's of potential for screw-ups and trashing a big dollar investment.

For now I'm sticking with plain old ordinary, deep cycle, lead acid batteries. No AGMs, no lithium, no fancy technology that will die if you over charge, under charge, over drain, under balance, don't remember this or forget that.

I have 675 amp hours of deep cycle 6V LA batteries that cost me about $550. Should be good for at least 5-7 years unless I forget and leave the lights on for a month without a charger and kill them (yes I've done that ). Then $550 and I'm good as new as opposed to 3X or 10X the cost.

[ebaugh]

Originally Posted by mcarling

The same could be said about lead acid batteries -- except that 12V lead acid batteries have 6 cells that need to be monitored for maximum life, not 4 cells.

The reality is that the hassle of monitoring individual cells to squeeze some extra life out of the batteries deters almost everyone from monitoring individual lead acid cells. I expect the same will be true for LiFePO4 cells once the market grows past the early adopters who like to tinker.

The other reason is a good charging regimen removes any need to monitor cell voltage for FLA. But until the pricing is similar where you can afford to kill one, and the full risk of overcharging is completely understood, I think monitoring is the only way to go. Like to tinker or not...

[Khagan1227]

Originally Posted by Don L

I did read it, but am looking for useful advantages.

Me too, but I'm looking for the article(s) with the answers to the questions on post #15.

Seriously, I'd rather haul off a bunch of light little batteries than 4 that weigh 100+ lbs when the time comes to replace the battery bank.

Also, I've read several reports that say LiFePO batteries have 10+ x the cycle life. So, while they cost 4 times as much, they might last 10 times as long with more usable power per charge and a faster charge/discharge rate.

[ebaugh]

Originally Posted by Khagan1227

Also, I've read several reports that say LiFePO batteries have 10+ x the cycle life. So, while they cost 4 times as much, they might last 10 times as long with more usable power per charge and a faster charge/discharge rate.

Maybe 10x a group 27 "deep cycle" battery from Sam's Club. I will be happy to see 3x my old Trojan golf carts. And there may be little additional cycle life compared to real 2V traction cells (forklift batteries).

Anyone who can say 10x without any qualification is drinking kool aid.

[nimblemotors]

Originally Posted by Don L

I did read it, but am looking for useful advantages.

Lighter and smaller are of no interest to me. I already have the space for batteries and they aren't taking enough space that "saving" 2 square feet matter in a location not all that useful for something else. And saving 50-100 lbs on a 43' boat isn't of concern (I don't see how 100 lbs of anything could "clearly" rule out anything on cruising boat).

I'm rooting for you people who decide to spend the extra cash, but I'm still not seeing a return on investment.

Then flooded lead acid good enough for ya, you can stop looking, walk right on past the lithium battery store window.
My boat will have a LOT of solar, a lot of batteries.
For a light multihull, weight matters.

[Caracal]

Originally Posted by nimblemotors

Then flooded lead acid good enough for ya, you can stop looking, walk right on past the lithium battery store window.
My boat will have a LOT of solar, a lot of batteries.
For a light multihull, weight matters.

And even medium or heavy weight cruisers will benefit from thinking "reduce weight" at every turn.

To me weight matters regardless. But just as important is the ability to have much more usable Ah (yes, I'm not downgrading) for a given volume, and the ability to quickly charge the thing to most of its capacity, rather than trickle charging, making poor use of the alternator and diesel.

And when it comes to solar, I can either make do with less area covered in solar cells, or have the same area as for lead acids, but have a less lossy setup compared to lead acids, which (of course) again translate to faster charging times.

Other than initial outlay I can see no drawbacks.

[sailorboy1]

be real 100 lbs is worth saving at any cost!

sounds like a case of "we have to have the best", even if that really is a small improvement

seems that the extra money would much better be spent on some extra solar panels

[Ocean Diamond 2]

Hi Guys,
I thought I had the idea of this thread was going to be what to buy and where to place and how to start it all working but alas, I'm Lost.
I'm hearing a lot of debate about the pros and cons, yes that's all good but I'm sold.
I've a plastic euro cubby house and need more power that uses less space so I can get the admirals ice maker to work at sea.
Do I just go on flea bay and buy what pops in the search or do any here have the list?
Not bitter and twisted just not a techo.
Keep Smiling
Derek

[Cotemar]

Maybe this will help jump start the battery revolution.

Battery Breakthrough Offers 30 Times More Power, Charges 1,000 Times Faster.

http://mashable.com/2013/04/17/battery-breakthrough/

BBC News - Super-powered battery breakthrough claimed by US team

[mcarling]

Originally Posted by Don L

I did read it, but am looking for useful advantages.

Lighter and smaller are of no interest to me. I already have the space for batteries and they aren't taking enough space that "saving" 2 square feet matter in a location not all that useful for something else. And saving 50-100 lbs on a 43' boat isn't of concern (I don't see how 100 lbs of anything could "clearly" rule out anything on cruising boat).

I'm rooting for you people who decide to spend the extra cash, but I'm still not seeing a return on investment.

LiFePO4 batteries are also much safer than lead acid batteries, in addition to the advantages listed in the several previous posts.

[mcarling]

Originally Posted by ebaugh

The other reason is a good charging regimen removes any need to monitor cell voltage for FLA.

Again, same for LiFePO4.

Originally Posted by ebaugh

But until the pricing is similar where you can afford to kill one, and the full risk of overcharging is completely understood, I think monitoring is the only way to go. Like to tinker or not...

Monitoring the overall bank, sure, but my point was about the claimed need to monitor the voltages of individual cells.

Batteries like the 12V 90Ah model which inspired this discussion have been for sale for a few years now. I have seen no evidence that divergence of cell voltages is a bigger problem with LiFePO4 than with lead acid. In both cases, I think the cost and hassle of individual cell monitoring is difficult to justify.

[transmitterdan]

I'll take a stab at answering the OP's question.

As of this date there is no "ready to buy" kit or even a bill of materials for a DIY LiFePo battery system for any "standard" boat.

The reason there is no mass market product available at any retailer is simple. The investment required to design, manufacture, market, warrant and service a LA alternative solution is too high, the market size too small, and the average boater too casual to make a profit. If it were not so someone would do it.

When you see a kit or list of parts available at West Marine, Defender, Fisheries Supply or (insert your favorite chandlery here) then you will know it is time for the "rest of us" to think about switching from LA.

[K_V_B]

Drop-in replacements for LA batteries exist. They are expensive though:

http://www.victronenergy.com/upload/...3%20-%20EN.pdf

So the wait is for the manufacturers to have milked the early adopters enough so that the price can go down, and "the rest of us" can afford them too...