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Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade A?)

Posted: Feb 09, 2015 6:26 pm
by okashira
I'm looking to buy a newer Model S salvage pack and part out the cells.

The cells are probably NCR18650BE
specs: 3200mah, 3.6V, ~10A cont, ~15-20A burst (P85D does 20A for 5 seconds)

The cells in a Model S are babied, thermally controlled and with a very good BMS system. They should be is essentially new condition, as owners of newer packs have basically seen no range degradation.
I would be testing them on my DC programmable load, of course and sharing their performance (let's assume they are similar to NCR18650BE for this thread for now)

I can offer heat shrink wrapping and basic pack assembly via spot welding for those interested (waiting on spot welder from Riba :-D)

Just curious what kind of market there is here for this type of cell before I move forward.

Re: Tesla Model S Cells - Interest? (NCR18650BE Grade A?)

Posted: Feb 09, 2015 6:30 pm
by cal3thousand
There should be plenty of interest, but you should post in 'used' since these are not new cells.

Also, how to you plan on shipping them? There are strict regulations for shipping lithium packs.

Re: Tesla Model S Cells - Interest? (NCR18650BE Grade A?)

Posted: Feb 09, 2015 6:31 pm
by Ykick
I'm beginning to look into spot welded cans instead of the HK stuff so any talk of high rate, quality and simple spot welding service grabs my attention.

Re: Tesla Model S Cells - Interest? (NCR18650BE Grade A?)

Posted: Feb 09, 2015 6:42 pm
by okashira
Well, I have not researched shipping much, but I would try to find the cheapest way possible. I am sure shipping within the states would be not be expensive.
I could offer local pickup of course if you're near Houston.

On new vs. used... good point. My expectation is to sell them on their "as-is" condition (via test results) and selling as used or new would be a little unfair, but you are right, technically they would be used.
Hell how do you know the "new" NCR's bought from china are not pulled from packs? :-D

I hope to do this to benefit the community here (by offering true grade A cells cheap,) and benefit myself by getting some cells for my self cheap and make a little extra to cover all the labor, risk and time involved.

I know a-lot of folks have concerns over 18650 packs because of assembly issues, which is why I want to offer spot welding. I could even test the whole pack as a whole under a high load before sending it out.

One of the things that makes me interested in getting these cells from a Tesla is that I expect their performance to be EXTREMELY consistent cell to cell, reducing balancing issues. This is because Panasonic has made billions of the exact cell by now and their mfg is top notch.

Ive tested some NCR18650BE's from China:
Image

They perform like PF, with more capacity. After 5 cycles no measurable loss in capacity (included two 10A runs)
My hope/expectation is the Tesla cells should perform better or the same as the China cells are probably "rejects."

They are about 45-46g per cell, so..
~255 W-h/kg
~775 W/kg continuous (you'd want some small air flow for this, they do heat up with no airflow)
~1100 W/kg burst

I think they come out to triple the capacity per weight and volume compared to A123 cells, and something like 66% of the power per volume/weight.

Re: Tesla Model S Cells - Interest? (NCR18650BE Grade A?)

Posted: Feb 09, 2015 6:54 pm
by okashira
Breaking news... the guy accepted my offer on the pack we were looking at. It's a newer one (Vin 21XXX IIRC) from a P85 performance model.

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 09, 2015 7:18 pm
by Ykick
I need to catch up on can pack building methods but for welding I'd be happy with 2P, 3P or 4P welded groups and then I can solder the strips for my series connections, install BMS, etc. 'guess it's time to mock up some configurations and be ready to go if this happens? Please PM if/when things are close...

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 09, 2015 7:19 pm
by teslanv
Subscribed

Re: Tesla Model S Cells - Interest? (NCR18650BE Grade A?)

Posted: Feb 09, 2015 7:20 pm
by liveforphysics
They are unlikely to be the NCR18650BE.

Re: Tesla Model S Cells - Interest? (NCR18650BE Grade A?)

Posted: Feb 09, 2015 7:47 pm
by okashira
liveforphysics wrote:They are unlikely to be the NCR18650BE.
We're 99% sure they are. Well, what I should say is, NCR18650BE's are probably Tesla rejects. Or they are at least equivalent performance.

Please see the thread in the Battery forum on NCR18650BD for our sleuthing... (hint, performance specs match, cell vent style matches, they look exactly the same from photos)

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 09, 2015 8:17 pm
by okashira
Guy says the car has 2800 miles on it (P85), I am trying to get him to send a picture of the dash (batt is still in the car) showing the miles before I commit.

And see how much interest there would be for the cells here...

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 09, 2015 8:45 pm
by teslanv
Estimated price per cell and minimum quantity you'll sell?
Have you ever dismantled a Tesla battery before.
I've seen videos and it doesn't look easy...

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 09, 2015 8:58 pm
by okashira
teslanv wrote:Estimated price per cell and minimum quantity you'll sell?
Have you ever dismantled a Tesla battery before.
I've seen videos and it doesn't look easy...
I'm not worried about the dismantling part. :-D
In big qty (e-bike size), probably ~$3.5 per cell, shipped (to USA) for bare cells.
That's quite a bit lower then shipped from China.

We'd be selling most. (6400 or so probably.)

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 09, 2015 9:15 pm
by ohzee
I would be very interested. Just seems like a big undertaking. Hopefully you have more then just yourself for the project.

Id also want to feel good about knowing who you really are with confirmation.

If that's an issue count me out and call me paranoid.

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 09, 2015 9:24 pm
by okashira
ohzee wrote:I would be very interested. Just seems like a big undertaking. Hopefully you have more then just yourself for the project.
Indeed there will be a lot of effort with packaging and shipping. Obviously I would like to see larger orders for bare cells, but I think with practice, spot welding a pack can be done quickly and reliably. Note, no way would it be 3.5 per cell for a welded up, & tested pack... ;-) MAYBE ~$4.10 per cell, depends on time/cost. I'll have to make a pack first.

I don't mind selling any quantity, but I would charge more for a very small quantity. Based on the prices at amazon, ebay, etc, I would still undercut chinese cells and for grade A cells, seems like a win...?

Heat shrinking them could be done quite quickly, but adds ~.15c to the cell cost by my calculation using bulk chinese heat shrink.
I do want to try a pack where they are welded up bare, with layered Kapton tape separating the parallel sections. That would keep weight, cost, size minimum and heat transfer may be better.

Edit: yes I am not going in alone, but we do have full time jobs. Most work would be done on the weekend.

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 09, 2015 9:38 pm
by mvly
Interested! Keep us posted. Even if i decide not to buy, i like to see how tesla are builsing their cells.

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 09, 2015 10:43 pm
by flathill
You are not going to be able to tear out the individual cells very easy (or maybe not at all) as the cells are glued in place. How much would one complete 24V module go for?

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 09, 2015 10:47 pm
by okashira
flathill wrote:You are not going to be able to tear out the individual cells very easy (or maybe not at all) as the cells are expoxied in place. How much would you sell one 24V module for?
If they are epoxied, it would be to a very smooth metallic surface (the cells look almost polished.)
I expect with the right solvent and care they will come free. Also, the epoxy only covers one side (approx 30% of the side of the cell) meaning it would be easy to get ahold of the cell and saw through the epoxy so it can be cleaned off with solvent later. (yes, we've thought this through, lol)

As for one module, shoot me a PM, I would sell a whole module no problem.

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 09, 2015 11:35 pm
by okashira
I'm off to bed. If you're interested, please PM or reply with

-How many cells you'd be interested in
-What condition... bare, heat shrink-ed, or built-pack
-The level of confidence you'd order cells (assuming they are as described, I will provide test data)

Assume $3.50 per cell for 150 cells min unwrapped and not welded (slightly higher for lower quantity)

I won't hold it against anyone if they said they'd buy cells now and have to cancel later, I just want a gauge. So please give an accurate level of confidence ...
We are looking at about 3 week before we'd be able to start to ship cells, FYI.

For folks concerned about my reliability: I have 10 years of 100% feed back on Heatware and eBay.
I will offer local pickup discount for those in TX, and small orders for the nervous.
Heatware: http://www.heatware.com/user_directory. ... Button.y=0
ebay: jdawn11
Also good feedback on Amazon (I will list cells there as well.) One negative there because of a vengeful person that I had to cancel their order and refund their money. Ha.

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 10, 2015 2:47 am
by Mark-az
100 cells.
If you can spot weld into 4p that would be great.
I'd like to know shipping obviously! I might pick up even if I am not really local...

I too have heard the packs are difficult to disassemble... Hoping you find it easy...

Edit:
Just noted that you asked for a pm, sorry.
Of you'd pm the answer I'd appreciate it.
Thanks,
Mark

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 10, 2015 10:33 am
by okashira
pm or reply is fine, thanks

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 10, 2015 7:21 pm
by okashira
Small update.
The pack we are looking at; the guy is going to send us a video showing the car on with the miles on the dash and showing the battery sticker so that we can ensure that it's a newer pack with little use. This won't happen until late this coming weekend due to logistics of the owner.

The cells are not tab welded! Each cell has a single short (~1cm?) aluminum wire friction welded to the center of the positive terminal and negative terminal. This could actually prove quite useful as this wire could be soldered to anything without impacting the cell, for those who want to purchase bare cells. If you don't want it, just cut it off.

They also don't appear to be epoxied, rather, clamped, thankfully.

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 10, 2015 11:56 pm
by eleven6
I'm interested in just the bare cells, at least 160 of them. Wonder how long the packs have been sitting unused?

Cool thing about these cells in particular is the bonus bragging rights. When showing off the ebike you can be like "yeah it actually runs off of batteries from a Tesla Model S!"

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 11, 2015 12:06 am
by Mark-az
Good news on the short Al tabs.
I will not need the cells tab welded into 4 piece units with those tabs.
I'll up my number of cells to your min qty too.

Mark

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 11, 2015 12:01 pm
by 100volts+
Subscrbed

Re: Tesla Model S Cells - Interest? TX, USA NCR18650BE Grade

Posted: Feb 11, 2015 12:04 pm
by ohzee
I was concerned about sales history and tbh I keep waiting for devries to surface or try to screw people re: buying from people on here.

After talking with okashira via pm and his previous post he seems like he is more then comfortable giving whatever info
is needed including as he stated picking up cells at his home. Thanks for the positive response to my questions.

Look forward to how this unfolds.