Tesla House Battery

[skipmac]

Originally Posted by CharlieJ

I need to buy a bigger BS meter shunt. My original shunt burned up with post #10. ;-)

I think that post actually transcends standard BS and requires a whole new kind of meter. To start it would have to be wrapped in tinfoil and would require calibration by a tech certified in paranormal activity.

[TreblePlink]

I would NEVER buy a used battery.

[Melissa36]

Originally Posted by K_V_B

Damn. Now I have to get my ******** meter unstuck again...

Oh, ok. It's wrong. That's why "wind" (as in air that blows) is saying to you "wind" (as in rotate).
The periodic "table" actually functions like this:
Periodic Table Database | Chemogenesis

See "The Case Against The Nuclear Atom"
D. B. Larson: "The Case Against the Nuclear Atom"
for the technical fallacies of the bogus nuclear atom model and the electron. Also, see "America's Secret Establishment" by Antony Sutton for an explanation of its fabricators.

Anyways, I was just explaining some of the errors in the Secrets of Cold War Technology book, which is otherwise spectacular.

[TheThunderbird]

Originally Posted by Melissa36

Oh, ok. It's wrong. That's why "wind" (air that blows) is saying to you "wind" (as in rotate).
The periodic "table" really functions like this:
Periodic Table Database | Chemogenesis

See "The Case Against The Nuclear Atom"
D. B. Larson: "The Case Against the Nuclear Atom"
for the technical fallacies of the bogus nuclear atom model and the electron. Also, see "America's Secret Establishment" by Antony Sutton for an explanation of its fabricators.

Anyways, I was just explaining some of the errors in the Secrets of Cold War Technology book, which is otherwise spectacular.

does it all pertain to having better batteries? Thanks

[belizesailor]

Originally Posted by TheThunderbird

does it all pertain to having better batteries? Thanks

Only in a vortex.

[K_V_B]

Originally Posted by Melissa36

Oh, ok. It's wrong. That's why "wind" (as in air that blows) is saying to you "wind" (as in rotate).
The periodic "table" actually functions like this:
Periodic Table Database | Chemogenesis

See "The Case Against The Nuclear Atom"
D. B. Larson: "The Case Against the Nuclear Atom"
for the technical fallacies of the bogus nuclear atom model and the electron. Also, see "America's Secret Establishment" by Antony Sutton for an explanation of its fabricators.

Anyways, I was just explaining some of the errors in the Secrets of Cold War Technology book, which is otherwise spectacular.

Will you stop doing this? You broke it again!

[TheThunderbird]

You all know how easy it is to cancel a contributor :-)

[Melissa36]

It's sad how a lot of people end up treating others as "adults" after they were raised by parents who didn't care about them.

[Sailmonkey]

Do the vortices contain light or dark crystals?

[Pete7]

Theo, pop down to Sams Club and buy yourself a couple of 6v golf cart batteries. Come back in 6 or 7 years and let us know how you are getting on with them. With the change left over buy something less risky, like a fraction of a bitcoin.

Pete

[Melissa36]

Originally Posted by Sailmonkey

Do the vortices contain light or dark crystals?

Good question. Which is it?

[john61ct]

Originally Posted by hellosailor

Tesla packs are designed to be used with a battery management system AND an active liquid cooling system, they are not designed to just plug into an alternator. And that cooling system is also critical. FWIW.

^^this

One day, likely within two years, the smart open-source hardware engineering types will likely have kickstarted projects allowing EV packs to be used for DIY low-voltage House banks.

But I doubt I would trust them for use on a boat for at least a few years after that point.

An off-grid home or even RV/camper/van is a lot safer context for such experimentation.

[john61ct]

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 agree, but the more knowlegeable the member, the less good they would have to say about using even new OOTB EV packs on a boat, much less recycled

[theo886]

Thanks everyone for all the interesting responses.

First I'll apologize if you felt the question should have been posted in an established lithium thread. I've been doing my research and searched throughout the forum and hadn't found these batteries mentioned. Since their availability is a fairly new development and their $/kWh is a bit of a game changer I thought they deserved their own topic.

I welcome all comments, especially the critics, but I'd like to focus on what it would take to put together a safe and reliable system before jumping to a judgment that its not worthwhile.

So a few points made already:

Originally Posted by TreblePlink

I would NEVER buy a used battery.

I would agree with you if I were buying this pack off ebay from some Tesla that was wrecked in a flood and the condition isn't well known. But these are being sold by a fairly reputable company in the EV world, and they have a 1 year warranty that should protect you from getting a dud pack. I've emailed them asking for more information on exactly where they are sourcing them and how they are able to guarantee their condition, I'll let you know what I hear.

Originally Posted by hellosailor

Tesla packs are designed to be used with a battery management system AND an active liquid cooling system, they are not designed to just plug into an alternator. And that cooling system is also critical. FWIW.

I do think a BMS will be required as a safety precaution, but I don't believe active cooling is going to be necessary for the type of loads it will see as a house battery. The pack is rated at 500 amps and meant to run an EV, we won't be drawing nearly as much.

From the site- "They have an integrated liquid cooling/heating system, but they can also be air cooled in light duty cycle applications."

The fact that they already have the heating/cooling circuits built in is a huge advantage. If for some reason I do find that my usage is overheating the batteries, the BMS and integrated thermistors will catch it and shut the battery down. Adding a cooling loop isn't as hard or expensive as it might sound. I actually expect low temperature to be a bigger issue when charging. I'd like to have it set up so that if the battery is too cold to charge, the source is disconnected and the heating loop is activated.

Originally Posted by K_V_B

Tesla uses lithium - cobalt batteries. These have the advantage of providing the highest power density, and the disadvantage of being a real fire hasard if you are not extremely careful. I would not use these in a DIY project...

I agree this is the biggest downside, but without the lithium cobalt technology we would not have this great price and size. With this hazard there has to be multiple layers of safety. The fact that it is a well made, double fused, Tesla battery pack is a great place to start.

The cobalt cells need to be provoked by charging them to a higher voltage than they are rated in order to combust. So I plan on only using charging source controllers (shore and solar) with programmable voltage limits so that they should never send a voltage higher than the pack limits. I also plan to program them to leave a buffer on both the high and low side of the charge. So if the max voltage is 25.2V then I will set the charge limit to say 24.4V which is about 85% full. This will keep the cells a safe distance form the voltage limits as well as make the battery happy and last longer as it doesn't like resting at full charge. And since I am getting so much more capacity for my money with these packs, I don't mind giving it a little more buffer than I would with a LiFePo4 pack.

I think for alternator charging, since I have a 12V vehicle I am going to send the 12V through a small inverter and feed the AC current into my charger which will then convert it to the 24.4V required. I know I am wasting some energy converting back and forth, but it seems to be the safest way to ensure that the charging voltage is controlled (and I plan to only charge off the alternator when absolutely necessary as it is the least efficient of all charging methods)

Then as a backup you have the BMS. If either the charge controllers fail to regulate the voltage, the BMS will identify a high or low voltage threshold set slightly outside the controller limits and open the contactor to the loads or sources depending. It will also monitor cell temps and balance cells.

What do you all think? Am I missing anything?

Although intriguing, I think we should pivot away from talking about vortices, I already go down enough rabbit holes reading about lithium setups

[john61ct]

The DIY EV forums have more specific knowledge on these packs.

Volt, Leaf and Prius packs are a bit further along in the reverse engineering timeline.

I think you're underestimating the technical challenges involved in doing things safely.

Also the costs incurred

both financial and in energy inefficiencies

of converting voltages up and down, even sticking to DC only

And powering an inverter to run a charger sounds not just out of the box, but IMO craycray.

To do this right will take very high level engineering and electrical skills, and a lot of time and money spent.

Not saying at all that it can't be done, but if that prototyping resources are going to be invested, IMO only the payback of potentially founding a profitable company would justify it.

For a once off personal project, investing $3-4000 in a properly designed LFP system would be cheaper, sensible and yield a much better result.