Tesla House Battery

[beckett]

I have been contemplating installing a Tesla battery module on 53 feet sailboat. Just to play around I purchased a used Tesla battery module from 2015 Tesla Model S with 12,000 miles on.
After researching and playing with the battery I tried to develop a safe electrical schema that would allow me to use it on a sailboat. Here are some thoughts and the underlying challenges of using a Tesla Model S battery module:
1. Do not attempt this unless you have an electrical engineering knowledge, this is NOT by any means a "drop-in" battery solution. There is NO built in BMS or protection from overcharging, over-consumption and low/high temps!
2. If you decided to go with the Tesla battery module and have 24V boat consider every electrical device on your boat and understand what range of effective voltages it needs to operate. The Tesla Model S battery module is 74p6s which means you have 444 18650 cells connected: 74 parallel and 6 modules in sequences. That is one module short from needed 7s configuration, this means you have an effective voltage range of 19V to 24.4V(where I feel the battery could be safely used). This range might be adequate to run all the navigation electronics as they typically can perform in 12V to 30V, an invertor like Victron which is 19V cutoff voltage, however, all other DC driven motors might experience chronic under voltage issues.
3. The battery's operation would be safer if you separate your charge bus and consumption bus in two and protect the battery from overcharging( never charge it to more than 25V the absolute dead max is 25.2V) personally I feel the comfort zone is 24.4. Never discharge it less than 19(dead at 18V) Implement a battery disconnect circuit that would disconnect your battery from the charge bus or the consumption bus if above charging/discharging scenarios would happen,
4. Never charge the battery at close to freezing temps! Some have been using an engine warming blanket that is set to 50F and automatically triggered when the temps drop to 40F or so(that is if you don't want the complexity of using the liquid cooling/warming system. )
5. If you have typical 3 ways to charge your batteries: via Main engine's alternator, the shower power charger and solar. You need to make sure you can control voltages and set to safe limits in my case not to exceed 25V(you will extend the life on the battery if you charge to 80% or ~24.4V. There is no float for this battery so make sure you can control your charger and stop charging when you hit your goal voltage. This could be tricky with the alternator .,. you need an alternator with an external voltage sensing and a smart controller that you can configure, or you need an ability to divert your charging current to another lead-acid battery once you hit the desired voltage, otherwise, you going to burn your diode bridge.
6. Once in a while, you would need a BMS in order to balance multiple cells and avoid overcharging or discharging them as the voltage differences occur due to internal resistance differences of individual batteries. This could be easily accomplished either by manually using something like manual Tenergy 5-in-1 cell meter or full-blown BMS like Orion BMS.

Sorry for all the typos and misspellings ... this was not typed on an iPhone.

[savoir]

Forget Tesla. That company will be bust by New year. Take a look at Sonnen battery products. Sonnen was just bought out by Shell which is a good sign.

[sparrowhawk1]

https://youtu.be/bMDkPb09oZs

Billionaire investor says different about Tesla.

[john61ct]

Only one thing is certain.

The future is known to no one.

[savoir]

Originally Posted by sparrowhawk1

https://youtu.be/bMDkPb09oZs

Billionaire investor says different about Tesla.

What was it that PT Barnum had to say ? While I think of it let's take a look at what is actually happening at Tesla.

Only a few days ago on March 1 Tesla had to make a loan payment of a massive $920 million but at what cost ? Merely days before that in February Elon Musk took out personal mortgages totalling $61 million. Might it be that the corporate loan payment could not be met without a huge shot of Musk money ? That now takes his total personal loans above $500 million.

Then we have the new model Y released this week with great fanfare. Will the first ones be available next month ? No. In three months ? No. Six months ?
No. The factory to build that model has not even been built yet so the first units might well be 18 months or more away if ever and anybody wanting to buy one will be obliged to pay a fee of $2500. Could this be another cash grab by an ailing Tesla ? Remember those fancy electric trucks announced in 2017 with a request for deposits ? How many are on the road so far ? None.

Good luck to Tesla customers. They might just need it.

[sparrowhawk1]

In the video the billionaire talks about one of his high paying Investments that didn't pay off anything for 3 years. The Mega Battery Factory is going to take time. If it's anything like his dream it will change the world. Did you know Elon's partner is Panasonic?

[sparrowhawk1]

drifting a little bit from sailing applications. https://youtu.be/zMJdxX6Lw9Q California is already producing more solar than can be used, also batteries are for more than just storage

[hellosailor]

john-
"The future is known to no one."
Just had an early corned beef dinner with the Oracle of Delphi. She begs to differ, and says the future is all there for all to see. Sort of a "Get your head out of the cockpit!" situation.

[piloto]

Originally Posted by Sailmonkey

Do the vortices contain light or dark crystals?

Dilithium crystals captain, give her all she’s got Scotty! What’s really important here is YOU CAN blow yourself up....

[newhaul]

Originally Posted by piloto

Dilithium crystals captain, give her all she’s got Scotty! What’s really important here is YOU CAN blow yourself up....

Yes but only if there is a cascade failure of containment with no way to vent plasma safely.

[savoir]

Originally Posted by sparrowhawk1

In the video the billionaire talks about one of his high paying Investments that didn't pay off anything for 3 years. The Mega Battery Factory is going to take time. If it's anything like his dream it will change the world. Did you know Elon's partner is Panasonic?

I know only too well. Here is a current assessment of the factory's success, or not.

https://buffalonews.com/2019/01/31/d...or-solar-roof/

Back in 2014 Musk was full of predictions for this factory and NONE of them have come to fruition except the approximately $1 billion bilked out of an ever obliging Governor Cuomo. Cuomo was particularly influenced by Musk's forecast of 4,900 employees but so far not even 1,000 have been hired. Lazy journalists will tell you that Cuomo only paid Tesla $750 million but they fail to factor in the taxpayer subsidized 10 year lease at $2/year. Nope no misprint - $2/year.

The forecast date for full production was Q1 2017 but it still hasn't happened and the recent layoffs of 50 people hasn't helped. The current media estimate of the number of Tesla employees at Buffalo is 400. Tesla continues to repeat its promise of 1460 employees in Buffalo by April 2020. Suuuuurre ! On top of that, delays in delivery of the Powerwall version of the battery system are currently 6 - 9 months.

https://buffalonews.com/2019/01/18/t...t-of-its-jobs/
https://www.greentechmedia.com/artic...ries#gs.1yi2m8

You quite correctly state that Tesla is in partnership with Panasonic but that relationship is not progressing to well due to Tesla's delays. Panasonic have begun selling their cells to all and sundry.

https://electrek.co/2018/08/08/tesla...gigafactory-2/

Telsa's Solar City cell and battery business is best avoided lest you become proof that PT Barnum was right.

[john61ct]

Are these the ones they switched to in the last couple years?

Decent-priced links to a source selling into the US would be appreciated.

[hellosailor]

I think Telsa is still filed under "Nice if it happens."

Elon's new investment in a battery company--not Panasonic--with a new technology is entirely separate from Panasonic's. And apparently there is literally a "line in the sand" at the gigafactory, once anything crosses over, it becomes Tesla property and has to be paid for. They are not quite in bed with each other yet, and Tesla as made some sophomoric goofs like announcing they'd close all their stores--without considering the lease obligations would keep going. Ooops.

There's also a continuing, and perhaps totally false, buzz that owners face large delays with deliveries (until recently) and with any kind of parts and service, especially if they are out of warranty. If Tesla thinks they can build a brand without supporting out of warranty vehicles...without a parts and repair network that can pretty much fix anything within a week...Cue the music, "Night Band on the Titanic".

The Tesla battery pack design, complete with liquid active thermal management, is designed for a purpose. And with the Model3 they already changed & improved that design. And they've restated charging parameters to increase battery pack life. Which, with the third-generation fast charger, may be yet another experiment in progress.

Elon's attack on the US car market was, and still is, amateur night compared to how the Japanese and later Korean car makers did it. Batteries? Uh, yeah, there are at least a dozen labs and firms with patents pending, each of which says THEIR product will change the entire marketplace. (And Elon's only bought one small one of those.)

I wonder how he does the thermal management on the Tesla they put up in Mars-Earth orbit?

[shaneinseattle]

Originally Posted by Dockhead

I disagree entirely! CF probably has the biggest collection of highly knowledgeable people on solar and LiFePo battery installations, and other types of battery installations, as they relate to boats, on the entire planet. There is a wealth of information of an extremely high quality in the archives here.

I feel you're probably correct...DIY folk that will either burn to the waterline and/or drown a thousand miles from shore due to their engineering missteps are likely to be a bit more careful than your average garage gearhead.

marinahowto.com is a really good site for lithium battery info, from a guy that knows what he's talking about.