Tesla Lithium battery question.

[a64pilot]

Have you lived in Europe?
I ask as from my perspective they have far fewer RV’s than the US.
They may or may not have more disposable income, they do in fact travel more and for longer times, but they spend less on other items to do that.
However their taxes are higher than ours, and I don’t think you have any idea as to cost of housing over there. Hint, in Germany anyway, it’s not cheap.
I’m afraid you think it’s a Utopia, but it’s actually just different is all. Not better, not worse, just different.

Shipping can’t be too much or things like grain would be sky high, and they aren’t. Cars for example, prices don’t reflect high shipping costs.
I think it’s tariffs, but don’t know.

[john61ct]

Yes I have lived only a few adult years stateside, several decades in Europe, and also Australia, which if anything is more relevant to the factors we're discussing

The innovation and build quality on Euro camper vans is fantastic, but most USian "RVers" are incredulous wrt pricing.

Same with Aussie off-road gear.

Yes of course taxes and tariffs are higher, that is of course a major factor.

But for mobile House bank use, and I'm pretty sure even golf carts, flooded lead is not used much at all, therefore low volume leads to necessarily higher prices.

AGM is more expensive and poorer longevity (especially over there), so LFP got a lot more attractive much earlier, thus that market is leaps and bounds more mature.

Higher volume brings pricing down

Virtuous spiral upwards, by now far ahead of the US.

Which we all know is also happening with alternative energy in general, we're just missing the boat on a huge driver of innovation and economic activity, thanks to FF lobbyists undue influence on US politics.

> Shipping can’t be too much

As a % of total value, getting a few lead batts around the world is much higher than other commodities.

[Dogscout]

So has anyone used a Tesla Powerwall on a yacht yet? Or even one of the others like the LG Chem RESU? It seem to me that one unit with a 10 warranty would be the way to go but I confess to knowing very little about solar and rechargeables.

I am curious if anyone has done this yet.

[Dadrock33]

Originally Posted by newhaul

if you decide to give it a try let us know .
Also let us know where you are so we can watch the papers for a battery caused marina fire.

. . . . or maybe just a fleeting glow in the sky . .

[Rumpi]

Originally Posted by john61ct

The packaged systems are also based on prismatics.

Just means avoid DIY based on cylindricals or pouches.

John I think you missunderstand something. Prismatics, cylindricals and pouches are all the same thing on the inside. How you package and connect the individual pairs of plates composing a battery is a matter of application. Rolling them up and individually stuffing them into metal cylinders is arguably the better method when it comes to mechanical stability and should be preffered in mobile applications. That's why prismatics and pouches need external compression devices, their case is not stable enough. A prismatic is nothing more than a big pouch (actually several in higher Ah batteries) stuffed in a plastic or aluminium case. And inside the pouch are many individual pairs of plates connected in parallel. Electrically it's all the same, and any BMS will see a collection of paralell cells as one, regardless of how they are actually packaged and connected. The real problem in building with cylindricals is handling and weight, and that translates into increased costs. The Tesla module is actually the best design from a pure mechanical point of view.

Realistically speaking LiFePO4 is a dead end and what we got is all there will be. Cost is not coming down, quality is not going up. So one must decide to either stay with LiFePO4 and pay the price or go with more advanced chemistries wich will cost less, because that's where the market and research is. Right now a Tesla module 24V, 233Ah, 5,2kWh is about 1000USD on the second hand market (the only way to get one). Other second hand ev cell blocks like Leaf or Volt go for even less. That's basicly less then half the cost of what you pay for LiFePO4. Yes they can catch fire. So can gasoline and propane and that does not stop people having them on the boat.

Dogscout, Tesla will not sell or install or offer warranty for a Powerwall in a mobile application, be it RV, boat or horse carriage. It's their policy.

[john61ct]

Yes I realize all that.

My point is a set of new prismatics made by Winston/Voltronix, CALB, GBS, A123 or Sinopoly, purchased from a trusted vendor

are a known-good platform to start from.

And that is afaic, the **only** non-lead House bank I consider safe enough to install on a boat myself,

and certainly the furthest out-there bleeding edge solution to recommend in a public forum read by mere mortals.

Now if a battery-specialising engineer was willing to risk his hide using secondhand / recycled cells, or another type of lithium chemistry, fine, just don't take the wife and kids along.

And saying "hey you can save money!" is a far from compelling motive, stick with lead if saving a grand or two is that important to you.

When the ABYC eventually comes out with their lithium specs, I'd put good money on something along those lines being included.

And before then, make sure if you are paying for insurance, your science experiments aren't giving them a great excuse not to cover you.

[Dockhead]

Originally Posted by DeepFrz

Dockhead, how much does a 12 volt LFP battery cost in your local? I see "Battle Born" advertised at around $950. US for 100 ah 12 volt, so probably close to $6,000. for a complete 400 ah system. That doesn't sound cheap to me. Maybe you can do better?

LiFePo4 doesn't come in 12v natively. People should not expect them to be like lead batteries, which you can just drop into a system designed for lead. You CAN buy them packaged up like that and with internal BMS etc. but this is a backwards approach which hardly makes sense. If you have a boat designed for lead and don't want to reconfigure it for lithium, then stick with lead, I would say.



Lithium power comes in 3.2v cells, and it is far more effective to buy them that way yourself and add the BMS. Much more straightforward than trying to adapt an electric car system.


As to what they cost in Europe, you can see here:


https://www.ev-power.eu/Winston-40Ah-200Ah/?cur=0


Roughly $323 each for 260 amp/hour cells. Buy four of them for a nominal 12v system. That's $1300 for the equivalent power of four Trojan T-105's, which cost about $800 in the UK.



You can't just drop in the prismatic cells -- you have to buy a BMS of some kind or another, buy or build a battery box and holddowns, and do some rewiring.



But the OP is not talking about a drop-in system, either. I don't think new, quality LiFePo4 cells are expensive enough to justify playing around with car packs, but YMMV, of course.

[a64pilot]

Originally Posted by Dockhead

LiFePo4 doesn't come in 12v natively.

Neither do lead batteries, in fact of course the word battery itself means a group of cells, packaged together to form a “battery” of cells.
So the 12V lead batteries you buy are just that of course.
So why do you not think it a logical way to package LFP?
Only rarely are single cell applications used, maybe cell phones etc, but anything much larger is of course a “battery” of cells.

I think that Lithium will mature into prepackaged batteries of 12V only because that is sort of s standard voltage, and may well contain a BMS that will either control a “smart” charger directly or do it all itself.

There are drop in replacements for golf carts I believe, how do they work? I’d assume the BMS controls a smart charger, golf cart people are already used to vehicle specific chargers, but that’s just a guess.

[a64pilot]

I think the whole point of people who want to use these car packs want to for their enormous capacity, way beyond what most boats do for their house bank.
The video posted of the guy with the Leopard, his use was obviously to run his AC power system with the obvious idea of running his three airconditioners, that takes HUGE capacity, car sized capacity.
I’m pretty sure he left his lead acid house bank alone.

The Chevy Bolt bank is a 60,000 WH bank, which if I do my math correctly (I’m bad at math) makes it a 5,000 AH bank at 12V.
What would it cost to buy 5,000 AH of LFP cells? That is the attraction of car battery packs, that you can get them from wrecking yards for pennies on the dollar.

[Rumpi]

Just a quick correction about pricing. The often cited ev-power.eu gives prices without VAT. Czech VAT is 21%, so a 260Ah Winston is actually 391USD. If we are talking about matching a Tesla pack in capacity, it would cost 3128USD. The rest of the costs, BMS, etc., are the same.

As to using used ev modules it's not only about cost. It's also often about the quality of the cells and sometimes weight. The Tesla packs are especially convenient, they weigh 55lb for 5,2kWh and come in the convenient to use 24V. As I said mechanicly their design is basicly mil-spec.
The Chevy Volt packs come in the 20lb, 22,5V, 1kWh and 20lb, 45V, 2kWh flavour. A 1kWh pack can cost as little as under 200USD. They have a good reputation for quality and are usually perfectly balanced.
Leaf packs come in "sardine cans" and are more easily disassembled to cell level.

Yes, all of this have the potential to thermal runaway, and could barbecue your boat if overcharged. Some people will want to use them, others will avoid them like the pest. Nothing to do but watch and learn, after all you can also do nothing about that other boats shoddy euro propane instalation, the cigar smoking, drunk powerboater with 100gal of gasoline in his tanks, or the rats nest of 40 years of speaker and telephone wire on some "old salt's" sailboat. Live and let live I say, and move away if you don't like the other boats systems.

What is actually the future are Lithium titanate chemistries that are used in some buses and ev's. They are as safe as LiFePO4, can accept much higher charging currents, and have better life expectancy. Disadvantages are weight and volume because they are only 2,7V. They also cost more new and are very rare on the second hand market. I hope this situation will improve over time, but I know this cells are highly desired on the solar storage market, so my hopes are not high.

[14murs14]

I think there's some major confusion here on exactly what a Tesla Powerwall is. It is a residential product designed for backup power in a home, often installed in conjunction with a solar array. It is not the battery system used in Tesla cars and not designed for mobile use like the car systems are. You can't interchangeably refer to Tesla's car battery and BMS systems and their Powerwall systems, it's not their car system simply pulled out and put in a case.

As to more prosaic problems, you can't go to your local Tesla store a buy a Powerwall, toss it in the back of your pickup and drive it down to your boat to self install. It must be purchased from and installed by a Tesla Powerwall dealer in a fixed structure. That last part is important, you need to either bribe a dealer to sell you the Powerwall without the install cost and lie about having installed it, or you'll have to pay to have it installed in a building, then rip it out and install it yourself in your boat, which also voids the warranty, by the way.

[nebster]

There's another reason people love the Tesla packs: they have the best volumetric density. If your space can fit the minimum viable size (one ~24V "sheet"), you can fit more energy per unit space with those than with anything else on or off the market, pretty much. For some applications, that can be the overriding goal.

I don't think we will see LTO achieve the scale gains that we are already enjoying with NMC and NCA cells. (They are an order of magnitude out on price after being on the market for some time?)

[hellosailor]

Tesla uses the 1860's in the older models, and the Model3 uses the slightly larger new cells instead. As it happens, these are made in the factory which Panasonic partners in, so yes you can call it a Panasonic cell, and yes you can call it a Tesla exclusive since they are absorbing all the output. For now. But as it happens Panasonic have built some of the best rechargeable batteries, in several chemistries, for a number of years. Which is probably why Tesla went with them.

The logic of using masses of flashlight batteries is pretty simple. First, it makes thermal management simple. There's a lot of surface area on each cell and they are packed, in Tesla's case, against "wavy" copper coolant pipes. So there's a LOT of thermal transfer easily made. The battery is both actively heated and cooled. IIRC in the Model3 the car is programmed to consume up to 80% of the battery's own power to keep it warm in the winter, if there's no external charge source. After that, Tesla figures "Good luck Charlie" you're on your own for what happens.
The other big factor is that the small cells typically are connected up by fusible links or fuse wire. If the cells go out of balance and any of them decide to run away, they'll blow the link and take themselves out of the battery, while leaving the vast majority of the other cells unaffected and operating. So they can afford to lose a number of cells over the 8? year guaranteed battery life. That might not be necessary with prismatic battery packs today, but it still works.

[duckpond49]

If you want a glimpse at what the Sailing Gods are up to check this out.
Technology | Daedalus Yachts
These folks are currently building a 78' Zero Emissions "foiling" cruising catamaran.
"Hydrogen is generated onboard and the energy is stored in BMW lithium battery banks."

[DeepFrz]

Here is a review of a Tesla battery module in use for 8 months in an off grid camper trailer. It has performed well and the installer/owner is very happy with the system.

https://www.youtube.com/watch?v=1QC8JAZXZGM