Mystery cell possible 15c discharge cells reported on evtv

hal2000

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Sep 20, 2012
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Jack, over at evtv has a gleem in his eye and a spring in his step, that can only mean he has found another goody to sell to the rest of us! How would you like a battery that is a third lighter, and has double the discharge rate of the grey calibs cells Jack has been selling for several years? Jack thinks you will like it quite a bit, and has ordered a couple hundred of these NMC cells after initial testing confirmed some of the manufacturers claims and he tested one cell at 1 C charge and discharge.
The cells showed a usable charge from about 3 to 3.9 volts and come in both a 100 and 50 amp hr cells . Cost is about double his grey calib cells, but so is claimed discharge capacity. http://www.evtv.me/
Apparently the rep for this new cell was a former Winston employee and now is working for a new company making these cells. Jack must not be the only one who knows about these cells as he mistakenly was shipped 10, 100 amp hr cells instead of the 6, 50 amp hr ones he ordered for sample testing. The other cells were destined for a unnamed source in UK...This is your que to chime in unnamed source! While The high c rate is as yet unconfirmed, they sound quite interesting.
What if any impact might these have? High power high cost, but for low cell count applications such as Elmoto, might these not be a viable alternative to lithium iron phosphate cells?
If something sounds to good to be true, it usually is, and in this case it is the cost,which Jack claims is about double the Calib cells, and asJack says " If you can find a higher price on any of my products on the internet.. we'll match it!. Any thoughts on where those of us with champagne taste and beer pocket books might obtain some of these cells? Any one have any knowledge of these cells and able to provide more data such as expected charge cycle life and methods of making up a pack with what appears to be a highly conductive non user friendly friction stir wielded casing?
 
This means i have to watch a 1.5 hour long video to get more details? ;)
Large format NMC is awesome if it is available on a continuous basis. This will be a big deal for conversions..

Ok, i'm off to watch the vid:

[youtube]Hz9D8iXYPbY[/youtube]
 
In the video, he says that he's charging up to 4.3v, but the manufacturer recommends 4.2v or 4.1v, but they settle down to 3.9v.
He says that it averages at about 3.6v. But the voltage curve is weird.

And the battery is about ~100whr/kg and cost twice as much as the lifepo4.

I'm going to venture a wild guess and say that these may be the kind of 'self balancing' cells that konions are. The fact that they charge up to 4.2v and then drop down to 3.9v indicate that there are some abnormal characteristics at play.
 
Jesus. 6 minutes of footage of them setting up to weigh something. :lol:
 
You have some of this correct. Apparently the attention span on Endless Fear precludes you watching a 90 minute video so I'll summarize.

Actually we ordered 6 100Ah LiFePo4 cells that purport 15C continuous and 20C for up to 10seconds. I'm excited about these and we have yet to receive them.

Instead, we received 10 LY-50Ah cells that are NMC cells - Lithium Nickel Manganese Cobalt Oxide (LiNiMnCoO2). This is a not unheard of recent chemistry in the 18650 space but not heretofore seen in a size this large or a prismatic cell.

We did a standard charge and discharge test at 1C noting the curves. We did a 3C fast charge to 95% capacity in 19 minutes with a 27F rise in anode temperature from 83F to 110F.

We have NOT confirmed the 20C as yet nor tested it.

It is QUITE ordinary for any lithium cell to charge to a charge voltage such as 4.1 or 4.2 volts and of course retreat to the open circuit voltage. These drop to about 4.00v static but quickly go to 3.9v at the slightest load. They have an almost linear discharge curve to about 3.3 v and then go very steep down to 2.5 - the recommended cutoff.

They purport to have 2500 cycles.


They weigh 3.8 lbs. We capacity tested one to 64 Ah - in a purported 50Ah cell.

So far they look remarkable. I have ordered 200 of them and still await the 20C LiFePo4 cells for testing.

IThey are roughly twice the cost of our existing CALB cells. ouch.

And yes, don't forget our Internet "price match guarantee". If you can find a higher price ANYWHERE on the Internet - we'll match it!

Jack Rickard
http://www.evtv.me
 
Jack, i watched the whole video, but i am 32 years old. I grew up having the amount of information in your shows selectively pruned into a 30 minute time space. Younger people have even a smaller attention span than me. Just something to consider.

Anyway thanks for clarifying the info. One thing you might want to look into is to see if they have a self-balancing characteristic as Sony's Konions do have - this is a BIG selling point. One could parallel these up to a couple kilowatt hours of weaker batteries of a chemistry that charges up to 4.1v, and ultimately come out of the deal with a larger battery that truly requires no BMS or attention from a top charge.

When you get those lifepo4 batteries in, please do let us know. I for one am curious, i know others will be.
 
Thanks for the corrections Jack, I have edited my initial post to correct errors. The streaming nature of your videos make it impossible to go back after a first viewing and check content without watching the whole show over. 90 min, the first time around, ok...180 min. ..at 11:30 pm....yawn.
 
Oh yea! Watched the video describing this "new" battery. A few notes:
  • he calls it "this year's next generation cell", a LiFePO4 improvement
  • its LiNiMnCo Oxide on the cathode chemistry, so still lithium-ion, but with improvements for C-rate, charge & discharge
  • C-rate is 20C pulse, 15C continuous, enough to satisfy EV racers
  • what he tested is the 50ah cells, but there's also 100ah cells available
  • 4.1 volt charge, 3.3 low discharge, average 3.6 volts, 3.8 lbs, so "high" power density
  • 3.6v X 50Ah = 180 Wh; 180 Wh/1.72kg = 105 Wh/kg (the power density)
  • he's in the process of adding these as a second line of cells, to the CALB, buying a hundred of them for resale initially, in the store by September; expects they'll go quickly
  • will be expensive, expect "sticker shock"
  • He's certified for shipping lithium batteries, using UPS; expect to pay for the service; add extra to ship to a residential address
  • he just bought a Tesla model S and showed it off; I'm jealous; Tesla using the latest Panasonic NCR cells (I'd always wondered about that)
The "strange" charge power curve from the vid:
evtv-vid.png
 
jrickard said:
You have some of this correct. Apparently the attention span on Endless Fear precludes you watching a 90 minute video so I'll summarize.

I thought it was your best video yet. Perhaps highest percentage good content related to batteries to date.

Actually we ordered 6 100Ah LiFePo4 cells that purport 15C continuous and 20C for up to 10seconds. I'm excited about these and we have yet to receive them.

Instead, we received 10 LY-50Ah cells that are NMC cells - Lithium Nickel Manganese Cobalt Oxide (LiNiMnCoO2). This is a not unheard of recent chemistry in the 18650 space but not heretofore seen in a size this large or a prismatic cell.

NMC pouches are used in large format pouches in the 2012 Zero's and 2013 Zero's, as well as GM Volt and a few other platforms. The voltage profile you've mentioned doesn't match the behavior of any NMC cathodes I've had experience with.

We did a standard charge and discharge test at 1C noting the curves. We did a 3C fast charge to 95% capacity in 19 minutes with a 27F rise in anode temperature from 83F to 110F.

That's a pretty substantial amount of heating in charge. When you say this was the anode temp, I'm assuming you mean the terminal of the anode that you could put a sensor on? Still outstanding though, it would be good to do a test at 2C and then 1 C to note the temp deltas and find what portion of that loss/heating was resistive. (hopefully all that charge heating was just resistive)

We have NOT confirmed the 20C as yet nor tested it.

It is QUITE ordinary for any lithium cell to charge to a charge voltage such as 4.1 or 4.2 volts and of course retreat to the open circuit voltage. These drop to about 4.00v static but quickly go to 3.9v at the slightest load. They have an almost linear discharge curve to about 3.3 v and then go very steep down to 2.5 - the recommended cutoff.

This curve you're describing sounds very different than anything I've tested or worked with. NMC stores a sizable amount of energy in the range of 3.9v to 4.15v, and has a small voltage buffering point around 3.30-3.35v where the last ~10-20% of it's energy is left (and typically too high of impedance to do much high-power stuff with) .

They purport to have 2500 cycles.

They weigh 3.8 lbs. We capacity tested one to 64 Ah - in a purported 50Ah cell.

That is outstanding!

So far they look remarkable. I have ordered 200 of them and still await the 20C LiFePo4 cells for testing.

IThey are roughly twice the cost of our existing CALB cells. ouch.

And yes, don't forget our Internet "price match guarantee". If you can find a higher price ANYWHERE on the Internet - we'll match it!

Jack Rickard
http://www.evtv.me


Exciting stuff Jack, thank you for sharing with us.

-Luke
 
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