# K2 Energy 'vs' Calb



## GeoMetric (Aug 13, 2010)

*K2 Energy Specs:*

LFP 73AH Power Battery (1P)
(28P of LFP26650P)
AKA: LFP 300HPS
6.61 lbs each 

For 1800A sag = 2.3V
For 1800A (268V sag voltage) = 116S (766 lbs)


*Calb Specs*

CAFI Series
For 1800A 12C:
40AH = (4P) 1920A (12 lbs)
60AH = (2P) 1440A (8.8 lbs)
100AH = (2P) 2400A (14.8 lbs) 

Weight for 1800A (268V sag) voltage pack? most likely way over 1200lbs.

For more info:
http://www.electricmotorsports.proboards.com/index.cgi?action=display&board=6576567&thread=14&page=2


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## Ziggythewiz (May 16, 2010)

To make it relevant to anyone not racing, can we see a price and cycle life next to each?


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## GeoMetric (Aug 13, 2010)

Ziggythewiz said:


> To make it relevant to anyone not racing, can we see a price and cycle life next to each?


Well, knowing the K2 Power Modules can produce 4200A burst, and Calb's cannot, I would say the K2 Energy Power Modules will last much longer at 1800A.


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## GeoMetric (Aug 13, 2010)

Ziggythewiz said:


> To make it relevant to anyone not racing, can we see a price and cycle life next to each?


[h2]LITHIUM IRON PHOSPHATE[/h2]
Lithium Iron Phosphate (LFP) is a special kind of lithium battery that addresses the 4 major issues with current lithium technologies: Safety, Life, Power, and Environmental Friendliness. 
[h2]LONG LASTING[/h2]


2000+ Cycles
3+ Year Shelf Life
Highest Energy Density LFP Batteries on the Market
http://www.peakbattery.com/technology.html

https://batteryworkshop.msfc.nasa.gov/presentations/Mod_LFP_Batt_Large_Format_App_JHodge.pdf

http://www.electricmotorsports.proboards.com/index.cgi?board=6576567&action=display&thread=14


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## rwaudio (May 22, 2008)

GeoMetric said:


> *K2 Energy Specs:*
> 
> LFP 73AH Power Battery (1P)
> (28P of LFP26650P)
> ...


You are correct, running some quick numbers I'd say 1300-1400lbs to get 1800A. 105-110 of the CA180 cells would do it.


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## GeoMetric (Aug 13, 2010)

rwaudio said:


> You are correct, running some quick numbers I'd say 1300-1400lbs to get 1800A. 105-110 of the CA180 cells would do it.


Thanks for the info.


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## GeoMetric (Aug 13, 2010)

rwaudio said:


> You are correct, running some quick numbers I'd say 1300-1400lbs to get 1800A. 105-110 of the CA180 cells would do it.


Now, put yourself in my shoes, needing 3000A. Calb's would never work, too much weight. I really like these K2 Energy Power Modules, they also sell:

[h2]3.2v[/h2]


Fully customizable packs. From single battery use to application in series with K2's BMS for custom projects.
These are the basic building blocks, perfect for modular designs requiring interchangeability
Whether high capacity or high power, K2 has a product suited to your needs
 
[h2]HIGH CAPACITY:[/h2]


26 Ahr
39 Ahr
51 Ahr
90 Ahr
 
[h2]HIGH RATE:[/h2]


42 Ahr
73 Ahr
http://www.k2battery.com/battery-packs.html


*All modules are built in USA!*


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## Elithion (Oct 6, 2009)

Comparing them for power applications:


K2 power cells: 44 s SDT
K2 energy cells: 81 s SDT
CALB cells: 163 s SDT
Therefore, for a given application, the K2 energy cells will be about twice as efficient as CALB cells and sag half as much, and the K2 power cells will be about 4 times as efficient as CALB cells and sag 1/4 as much.

Price: K2 cells are about 1.5 to 2 times as expensive as CALB cells (but don't quote me, as cell prices are quite variable).


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## GeoMetric (Aug 13, 2010)

Elithion said:


> Comparing them for power applications:
> 
> 
> K2 power cells: 44 s SDT
> ...


Awesome! Thank you.
I will be racing with them in 2013.


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## GeoMetric (Aug 13, 2010)

I am very very satisfied with working with K2 Energy, Mark Stoker, Jim Hodge always answer every question in a timely manner with proven data. The company is located:

1125 American Pacific Drive, Suite C
Henderson, Nevada 89074

Phone: 702.478.3590
Fax: 702.558.0180 
Email:[email protected] 

It's a blessing we have American companies willing to sell to the public.


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## palmer_md (Jul 22, 2011)

how does the 90Ah module compare to Calb on price? What is the price per Ah?


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## GeoMetric (Aug 13, 2010)

palmer_md said:


> how does the 90Ah module compare to Calb on price? What is the price per Ah?


Calb 100AH cell goes for around $150.00 to $170.00 each.

K2 Energy 90AH cell lists for $315.00, but I know when you place a large order the price does go down.


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## palmer_md (Jul 22, 2011)

GeoMetric said:


> Calb 100AH cell goes for around $150.00 to $170.00 each.
> 
> K2 Energy 90AH cell lists for $315.00, but I know when you place a large order the price does go down.


wow, double. that caught me off guard...I expected you to say around $200. I'll be interested in your testing with these cells.


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## Ziggythewiz (May 16, 2010)

Worse than that. $125 is overpaying for a CA100.


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## rwaudio (May 22, 2008)

GeoMetric said:


> Calb 100AH cell goes for around $150.00 to $170.00 each.
> 
> K2 Energy 90AH cell lists for $315.00, but I know when you place a large order the price does go down.


That's fairly high, but works for the right application I guess. I just bought a small pack of Calb CA60FI's at 73.20/cell. A 100Ah cell would be $122 making the K2 just a hair shy of 3x the price per Ah. For racing the cost is less of a concern if they work reliably though.

Is that price for a raw pouch? Or something ready to go into the car?


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## palmer_md (Jul 22, 2011)

rwaudio said:


> Is that price for a raw pouch? Or something ready to go into the car?


They build "lego bricks" like CALB/TS/Sinopoly... Inside are 18650 or 26650 cells all in parallel for a 3.2v "brick".


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## rwaudio (May 22, 2008)

palmer_md said:


> They build "lego bricks" like CALB/TS/Sinopoly... Inside are 18650 or 26650 cells all in parallel for a 3.2v "brick".


That's not so bad if they produce the power then, legit A123 pouches were significantly more than the usual prismatics then required connecting and packaging time and money.


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## Elithion (Oct 6, 2009)

These K2 batteries are pretty clever:


Like prismatic cells, they are easy to mount
Like cylindrical cells, they do not need constraint against expansion (because they are built out of small cylindrical cells)


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## Batterypoweredtoad (Feb 5, 2008)

Wouldn't the prismatic made of cylindrical cells have the worst of both worlds for cooling: the big plastic shell of a prismatic and none of the airflow benefits of a cylindrical? 

Also: is the Calb info based on the old Calb chemistry or new?


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## Elithion (Oct 6, 2009)

Batterypoweredtoad said:


> Wouldn't the prismatic made of cylindrical cells have the worst of both worlds for cooling: the big plastic shell of a prismatic and none of the airflow benefits of a cylindrical?


K2 batteries use hefty copper plates to interconnect cells and to conduct both heat and current from the cells to the terminals. In that sense, they are the same as prismatic cells, maybe a bit better. 

You are correct that non-encased small cylindrical cells have the additional benefit of convection cooling. Though, normally, batteries using small cylindrical cells are enclosed, and rely on conduction cooling through the terminals instead.



Batterypoweredtoad said:


> Is the Calb info based on the old Calb chemistry or new?


The Short Discharge Time article lists only the old SE cell technology: 163 seconds. The SDT for the new CA cell technology is 143 seconds (13 % better). 

While that 13 % improvement is good, it is not good enough to come close to the K2 cells, especially the power cells (which match the A123 M1 cells).


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## Batterypoweredtoad (Feb 5, 2008)

Thank you for the quick and informative reply!


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## DIYguy (Sep 18, 2008)

Elithion said:


> While that 13 % improvement is good, it is not good enough to come close to the K2 cells, especially the power cells (which match the A123 M1 cells).


After a fair bit of testing with A123 cylindrical cells, it's pretty obvious to me that they will not come close to most of the better RC lipo, for power. 
I love A123 cells, but for drag racing, with the lightest battery, and least sag, u gotta go with RC lipo. ( i know u don't want to use Lipo Ron, that's kewl, just sayin')

Elithion . . . have you done any testing with some of the RC lipo and if so. . how much better for power are they than your best contender (Kokam)?

Thanks.


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## Elithion (Oct 6, 2009)

DIYguy said:


> After a fair bit of testing with A123 cylindrical cells, it's pretty obvious to me that they will not come close to most of the better RC lipo, for power.
> Elithion . . . have you done any testing with some of the RC lipo and if so. . how much better for power are they than your best contender (Kokam)?


From a power application perspective,
Kokam > A123 M1 (cylindrical) ~= K2 power > K2 EV > A123 20 Ah (pouch) > CALB

(NOTE: Short Discharge Time is only one parameter to consider. I am not dissing CALB. On the contrary, CALB cells have a good value and are appropriate for most EV applications.)

Hobby LiPo cells are hard to pin down: unclear origin, no specs, uncertain repeatability, hyperbolic claims. If we tested a Turnigy cell, the results could not be trusted to apply to any other cell that happens to have the Turnigy name stamped on it. They may be fine; but, as a pro, I can't afford to go near them.

When we test cells, they come directly from a renown manufacturer: Kokam, Enerdel, Sinopoly, GBS...


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## winzeracer (Apr 3, 2012)

GeoMetric said:


> I am very very satisfied with working with K2 Energy, Mark Stoker, Jim Hodge always answer every question in a timely manner with proven data. The company is located:
> 
> 1125 American Pacific Drive, Suite C
> Henderson, Nevada 89074
> ...


That's good news. Thanks for the info, are the cells manufactured in the U.S.?


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## GeoMetric (Aug 13, 2010)

winzeracer said:


> That's good news. Thanks for the info, are the cells manufactured in the U.S.?


*The cells are produced by K2 Energy/ DLG Battery LTD under specific patents designed and owned by K2 Energy. Another words, you will not find the same cells at DLG Battery. Here is a press release:*

HENDERSON, Nev., Feb. 8, 2012 (GLOBE NEWSWIRE) -- K2 Energy Solutions, Inc. (K2 Energy), a leading, privately held US developer of rechargeable lithium ion battery cells, modules, packs and systems announced today the ongoing expansion of its US and foreign operations.
A photo accompanying this release is available at http://www.globenewswire.com/newsroom/prs/?pkgid=11604
In the fourth quarter of 2011, K2 Energy began a significant expansion of its research, development and manufacturing facilities driven by wide acceptance of its lithium iron phosphate (LFP) storage, military and mobility products. A key driver of K2 Energy's power mobility business is growth in orders for military, zero idle, and utility applications for which the company's technology is uniquely suited. 
To fulfill the demand, K2 Energy (a 2011 Inc. 100 company) is expanding its US footprint located in Henderson, Nevada and expects continued work force growth through 2012 that will complement the approximately 30% increase in staff already experienced during 2011. "It is very satisfying that we have been able to bring highly technical engineering and manufacturing positions to one of the most distressed job markets in the Country," noted Stewart Graham, Director of Operations and co-founder of K2 Energy. 
The company has also acquired land rights in Suzhou Industrial Park, one of China's best high technology development zones, and held ground breaking for the first phase of K2 Energy's manufacturing expansion.
K2 Energy is working with state and local officials to bring an even larger battery production facility to Henderson, Nevada to take advantage of the unique opportunities available in the area, including the growing concentration of clean energy technology companies and a skilled workforce. "We will work throughout 2012 to identify the location and continue the development process which, once completed, will bring hundreds of much needed manufacturing and engineering jobs to Southern Nevada in addition to architectural, construction and related trade jobs," concluded Mr. Graham. 
For more information about K2 Energy Solutions or any of its rechargeable battery options, visit them at the Electric Vehicle Symposium in Los Angeles, California, May 6th through the 8th, booth #931 or online at www.k2battery.com. 
About K2 Energy Solutions, Inc.: K2 Energy is a leading developer and manufacturer of advanced lithium ion batteries, cells, packs, modules and systems for a broad range of mobile and fixed energy storage applications and a 2011 Inc. 100 Company. K2's customers include electric vehicle makers, utility companies, industrial equipment manufacturers and government agencies, among others opting for the safe, clean, cost effective and reliable alternatives to current battery technologies. K2 is a privately funded corporation formed and headquartered in the growing green technology hub of Henderson Nevada, with manufacturing and assembly sites in Nevada, Finland, and China.

http://globenewswire.com/news-relea...nced-by-K2-Energy-Solutions-Inc-for-2012.html


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## GeoMetric (Aug 13, 2010)

DIYguy said:


> After a fair bit of testing with A123 cylindrical cells, it's pretty obvious to me that they will not come close to most of the better RC lipo, for power.
> I love A123 cells, but for drag racing, with the lightest battery, and least sag, u gotta go with RC lipo. ( i know u don't want to use Lipo Ron, that's kewl, just sayin')
> 
> Elithion . . . have you done any testing with some of the RC lipo and if so. . how much better for power are they than your best contender (Kokam)?
> ...


I have used RC "type" cells for racing with good and bad results. The first year, I had a 14P row of series built Turnigy cells catch fire on the dyno. Oli in UK had RC batteries burn his car to the ground, Lowell in FL had a fire in his Porsche with RC cells. IMO, will NEVER use RC or Lipo cells again.


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## Batterypoweredtoad (Feb 5, 2008)

Ron, Were all the Lipo fires you mentioned in packs built using series strings that were then paralleled?


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## GeoMetric (Aug 13, 2010)

Batterypoweredtoad said:


> Ron, Were all the Lipo fires you mentioned in packs built using series strings that were then paralleled?


Two fires where series strings that were paralleled, one was lipo cells paralleled then connected in series with a normal BMS. To my knowledge, the only company that produces a "safe" lipo cell is EiG, according to KleenSpeed. The lipo cells being used in their electric formula car contain a chemical (??) that prevents the cell from overheating which is the main factor with lipo cell technology.


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## rochesterricer (Jan 5, 2011)

Aren't the Dow Kokam cells a form of lipo as well?


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## GeoMetric (Aug 13, 2010)

rochesterricer said:


> Aren't the Dow Kokam cells a form of lipo as well?


Yes, and they will catch fire if overheated. There is a very thin line when using Lipo cells, if you cross it you will regret it. I am so pleased to not be using Lipo cells in 2013.


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## GeoMetric (Aug 13, 2010)

Inside K2 Energy Solutions!

http://www.youtube.com/watch?feature=player_embedded&v=bya43hpTmOk


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## GeoMetric (Aug 13, 2010)

My new cells will be arriving soon!


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## GeoMetric (Aug 13, 2010)

My K2 Energy Modules are complete and shipping to CT, pictures soon!


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## Karter2 (Nov 17, 2011)

Elithion said:


> From a power application perspective,
> Kokam > A123 M1 (cylindrical) ~= K2 power > K2 EV > A123 20 Ah (pouch) > CALB
> 
> (NOTE: Short Discharge Time is only one parameter to consider. I am not dissing CALB. On the contrary, CALB cells have a good value and are appropriate for most EV applications.)
> ...


Davide,
do you have any knowledge of these cells from GEbattery..
http://www.gebattery.com.cn/geb/EN/ProductList.asp?sortID=167&Sortpath=0,133,167
Vague info (3.3v ?) suggests they are LiFePo4, but with a very high (120) "C" rate claimed.
not a special "energy" cell, but could be a good " power" pack.


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## Ziggythewiz (May 16, 2010)

Karter2 said:


> Davide,
> do you have any knowledge of these cells from GEbattery..
> http://www.gebattery.com.cn/geb/EN/ProductList.asp?sortID=167&Sortpath=0,133,167
> Vague info (3.3v ?) suggests they are LiFePo4, but with a very high (120) "C" rate claimed.
> not a special "energy" cell, but could be a good " power" pack.


What vague info are you looking at? It specifically says LiFePO4. I'm guessing of the LiFePO4/Supercapacitor variety. Certainly an interesting find. 

If they can do all they claim I'd think all the drag racers would want them. 

Complete discharge in 15 seconds 

$30 ea


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## Elithion (Oct 6, 2009)

Karter2 said:


> Davide,
> do you have any knowledge of these cells from GEbattery..
> http://www.gebattery.com.cn/geb/EN/ProductList.asp?sortID=167&Sortpath=0,133,167
> Vague info (3.3v ?) suggests they are LiFePo4, but with a very high (120) "C" rate claimed.
> not a special "energy" cell, but could be a good " power" pack.


I didn't. Nice find, and incredible specs!

I included it in the chart of short discharge time for various cells.
Note that it beats all other cells.
Only ultra-capacitors are better performers in high power applications.


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## Hollie Maea (Dec 9, 2009)

Elithion said:


> I didn't. Nice find, and incredible specs!
> 
> I included it in the chart of short discharge time for various cells.
> Note that it beats all other cells.
> Only ultra-capacitors are better performers in high power applications.


So...who's going to test these and find out if it is legit?


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## Ziggythewiz (May 16, 2010)

I contacted them to get the price and was surprised how low it was. Waiting to hear back on ordering test amounts (as opposed to the 500 unit min order listed).


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## Yabert (Feb 7, 2010)

Elithion said:


> ... incredible specs!


I would believe it...

Around 5 Kw / Kg continuous...


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## Genius Pooh (Dec 23, 2011)

Ziggythewiz said:


> I contacted them to get the price and was surprised how low it was. Waiting to hear back on ordering test amounts (as opposed to the 500 unit min order listed).


plz send me price info 

thanks


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## Ziggythewiz (May 16, 2010)

They're $30 each. They generously offered to do an order as small as 300 units for testing purposes.


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## Genius Pooh (Dec 23, 2011)

Ziggythewiz said:


> They're $30 each. They generously offered to do an order as small as 300 units for testing purposes.


do you mean "LFP 73AH Power Battery (1P)" is just 30$?

really?? OMG it's almost 3 times cheaper than A123 wow!! 

Really??

so 1$ is 7.78 wh. it's 12 cent per watt. Hooray!! wow!!

Oh it's 7kwh for just 1000$ wow. I hope they offer more and cheaper. 
21kwh is enough for daily car.

Oh at next year I can make EV car hohoho..


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## Ziggythewiz (May 16, 2010)

Other suppliers list a minimum quantity of 100 , 10, or even 1.


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## Ziggythewiz (May 16, 2010)

Genius Pooh said:


> do you mean "LFP 73AH Power Battery (1P)" is just 30$?


No, it's a 6 AH cell for $30. Poor capacity for the $$ but supposedly unbeatable power.


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## Genius Pooh (Dec 23, 2011)

Ziggythewiz said:


> No, it's a 6 AH cell for $30. Poor capacity for the $$ but supposedly unbeatable power.


OMG sad... I thought it's new begin of EV conquerer T_T


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## Karter2 (Nov 17, 2011)

Ziggythewiz said:


> Poor capacity for the $$ but supposedly unbeatable power.


 Just mulling over some numbers..
Remember Rons K2 data..


> *K2 Energy Specs:*
> 
> LFP 73AH Power Battery (1P)
> (28P of LFP26650P)
> ...


 ..and the only price we have seen for those is $315 each,..
..so that pack is *$36,500* worth!! 

Now, taking the GEB cells on quoted specs..
1800 A needs 3p @ 600A ( 100C) per cell
At that output they sag to 2.5 volts
So, Rons 268 volts needs 110S to be the same
Total = 330 cells =* 250 lbs* ( @ 340gms each) !
And cost is 330 x $30 =* $9900*

Thats 33% of the weight... and 27% of the price ! 
6.5 kWhrs ..should be enough for 20-30 sec of race time ?

You could even go 4P 110S for a 2400 A ( 2800 max) pack ..and still be under half the weight of the K2 pack !


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## Genius Pooh (Dec 23, 2011)

Karter2 said:


> Just mulling over some numbers..
> Remember Rons K2 data..
> ..and the only price we have seen for those is $315 each,..
> ..so that pack is *$36,500* worth!!
> ...



Did you mean this battery? do you know cost of this battery??

I think It's good for military application ^^ hohoh


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## Yabert (Feb 7, 2010)

Karter2 said:


> Thats 33% of the weight... and 27% of the price !


Those numbers just confirmed than K2 cells are 5-6 years old technology...


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## GeoMetric (Aug 13, 2010)

Karter2 said:


> Just mulling over some numbers..
> Remember Rons K2 data..
> ..and the only price we have seen for those is $315 each,..
> ..so that pack is *$36,500* worth!!
> ...



I did weeks of DD on the company GEB and the cell GEB6619140.
I contacted the company requesting additional testing results, failure rates, etc...every "official" had a different set of specs and story, I asked to order 50 cells for testing they did not have in stock and would get back to me. In my opinion, GEB is a broker, they do not build the cells, that spells trouble for me. If they prove to be what they publish, yes they would be a good deal. For me I will use the guaranteed and proven K2 Energy cells.


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## Elithion (Oct 6, 2009)

I think I know how GeB does it: it managed to make an very _low _capacity cell, while leaving the current handling the same. Hence, the C-rating (ratio of max current over capacity) is huge.

The volumetric energy density is the worse we have seen in Li-ion: 109 Wh / liter (close to lead acid). The gravimetric energy density 56 Wh / kg, again the worse we have seen in Li-ion, worse than PowerGenix NiZn cells.

Proving that you can't rely on a single parameter to compare cells and batteries.


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## GeoMetric (Aug 13, 2010)

Karter2 said:


> Just mulling over some numbers..
> Remember Rons K2 data..
> ..and the only price we have seen for those is $315 each,..
> ..so that pack is *$36,500* worth!!
> ...


If I remember correctly the 100C rating of the GEB cell lasts only a few seconds before it drops like a rock, the cell will not deliver 600A for 9 seconds.


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## Ziggythewiz (May 16, 2010)

The spec says 120 C continuous, and shows a discharve curve of 700A from full to empty. You only get a little over half the sticker AH at that rate though.


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## GeoMetric (Aug 13, 2010)

Ziggythewiz said:


> The spec says 120 C continuous, and shows a discharve curve of 700A from full to empty. You only get a little over half the sticker AH at that rate though.


Take a good look at this data:

http://www.gebattery.com.cn/geb/EN/ProductList.asp?sortID=167&Sortpath=0,133,167

The 120C and 100C drop way before the battery is empty, the problem with these type is density, they only deliver huge amps for a few seconds. Even us drag racers need some density, atleast 9 seconds worth.


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## Yabert (Feb 7, 2010)

Ziggy, you aren't enough specific for Ron...
The specs says 700A for 15s or 600A for 24s.


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## GeoMetric (Aug 13, 2010)

Ziggythewiz said:


> The spec says 120 C continuous, and shows a discharve curve of 700A from full to empty. You only get a little over half the sticker AH at that rate though.


That statement makes no sense, if the AH drops so does the discharge amps..


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## GeoMetric (Aug 13, 2010)

Yabert said:


> Ziggy, you aren't enough specific for Ron...
> The specs says 700A for 15s or 600A for 24s.


Show me those specs?

Is shows:

100C the amps drop like a rock at 4.5AH
120C the amps drop like a rock at 3.2AH


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## Jozzer (Mar 29, 2009)

GeoMetric said:


> That statement makes no sense, if the AH drops so does the discharge amps..


 Not so - the C rating applies to the rated capacity of the cell, not the capacity remaining in it.

Your reading the graph wrong - what it shows is that voltage drops sooner (ie, cell is empty). So at higher discharge rates you don't get full capacity (more like a PB battery than a Lithium) - but you still get full current until it is empty..


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## GeoMetric (Aug 13, 2010)

Jozzer said:


> Not so - the C rating applies to the rated capacity of the cell, not the capacity remaining in it.
> 
> Your reading the graph wrong - what it shows is that voltage drops sooner (ie, cell is empty). So at higher discharge rates you don't get full capacity (more like a PB battery than a Lithium) - but you still get full current until it is empty..


I understand that, but amps is based on AH x C rating. If the AH drops so does the amps. I agree you get full current until the cell is empty, but the higher amps drain these cells very quick. The graph shows 6 points of amperage drop.


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## major (Apr 4, 2008)

GeoMetric said:


> Yabert said:
> 
> 
> > The specs says 700A for 15s or 600A for 24s.
> ...


Saying the same thing. Do the math.

( 4.5Ah / 600A ) * 3600 seconds/hour = 27 seconds

( 3.2Ah / 700A ) * 3600 s/h = 16.46 seconds

I just ran some single cell tests at 700A yesterday. I could make time to test a cell for you, after all it only takes 20 seconds.


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## GeoMetric (Aug 13, 2010)

major said:


> Saying the same thing. Do the math.
> 
> ( 4.5Ah / 600A ) * 3600 seconds/hour = 27 seconds
> 
> ...


So, you have these GEB cells at your shop?


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## major (Apr 4, 2008)

GeoMetric said:


> So, you have these GEB cells at your shop?


No, I've never seen one. You or someone would need to supply the test subject.


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## GeoMetric (Aug 13, 2010)

major said:


> No, I've never seen one. You or someone would need to supply the test subject.


Okay, so you never tested or pulled 700A out of a GEB cell.


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## Ziggythewiz (May 16, 2010)

GeoMetric said:


> That statement makes no sense, if the AH drops so does the discharge amps..


A is in no way dependent on AH. In fact, time has no bearing on Ohm's law.

It's called peukert. The bane of a floodie's existence. The higher the rate you remove current the less ah you can take out (as well as less total power due to sag). At reasonable C rates lithium isn't affected enough by peukert to bother accounting for, but at 120C it takes a big hit.


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## Ziggythewiz (May 16, 2010)

GeoMetric said:


> I understand that, but amps is based on AH x C rating. If the AH drops so does the amps. I agree you get full current until the cell is empty, but the higher amps drain these cells very quick. The graph shows 6 points of amperage drop.


You have that all backwards. C rating is based on amps and capacity (AH). Amps (I) = V/R

The graph shows voltage curves with respect to capacity used. There were 6 different constant current discharge profiles used to test the cells. When the voltage plummets enough to no longer supply that current the cell is empty.

You should read the labels on graphs, they mean something.


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## GeoMetric (Aug 13, 2010)

Ziggythewiz said:


> You have that all backwards. C rating is based on amps and capacity (AH). Amps (I) = V/R
> 
> The graph shows voltage curves with respect to capacity used. There were 6 different constant current discharge profiles used to test the cells. When the voltage plummets enough to no longer supply that current the cell is empty.
> 
> You should read the labels on graphs, they mean something.


I will be convinced when someone does independent tests on these cells. I do not trust data from some Chinese distributor. I have already stated when I contacted them, they provided different specs from different sales reps. I will stick with K2 Energy Cell Modules.


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## major (Apr 4, 2008)

GeoMetric said:


> Okay, so you never tested or pulled 700A out of a GEB cell.


I didn't say I ran a test on a GEB cell. I said I ran some 700A tests on some single cells. And offered to run a test, if someone sends me the cell. 



major said:


> I just ran some single cell tests at 700A yesterday. I could make time to test a cell for you, after all it only takes 20 seconds.


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## GeoMetric (Aug 13, 2010)

major said:


> I didn't say I ran a test on a GEB cell. I said I ran some 700A tests on some single cells. And offered to run a test, if someone sends me the cell.


Thanks for clearing that up! Please keep us informed if anyone buys these hot potato's for testing.


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## Ziggythewiz (May 16, 2010)

GeoMetric said:


> I will be convinced when someone does independent tests on these cells.


Understood. Me too. They need to be tested for claimed specs, safety in a max utilization scenario, and cycle life in a typical utilization scenario.

One good thing though is that they could be tested to 1000 cycles in 1 week while for most cells it would take months.


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## GeoMetric (Aug 13, 2010)

Ziggythewiz said:


> Understood. Me too. They need to be tested for claimed specs, safety in a max utilization scenario, and cycle life in a typical utilization scenario.
> 
> One good thing though is that they could be tested to 1000 cycles in 1 week while for most cells it would take months.


The data is awesome, but there is something about this company that is bringing up a red flag when I researched. One is the fact that they sell products with the A123 name, but never purchased any cells from A123.

http://www.gebattery.com.cn/geb/EN/ProductList.asp?SortID=156&SortPath=0,133,156,

Another is the "About Us" page with pictures of little work stations. I would rather have seen vacuum chambers with equipment assembling the cells.

http://www.gebattery.com.cn/geb/EN/About.asp


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## GeoMetric (Aug 13, 2010)

K2 Energy also opened a Chinese factory, but much different.








K2 is expanding with a new manufacturing facility now in Suzhou China.


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## Ziggythewiz (May 16, 2010)

GeoMetric said:


> Another is the "About Us" page with pictures of little work stations. I would rather have seen vacuum chambers with equipment assembling the cells.
> 
> http://www.gebattery.com.cn/geb/EN/About.asp


Those look like stock photos for an iPadish factory. I'm pretty sure you can't hand assebmble lithium cells no matter how little your hands or pay are.


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## Karter2 (Nov 17, 2011)

Ron, Even if their data is exaggerated 100%, you could still run double the number I suggested ...(6p, 110s ....300a per cell...50C ),...with a lot less voltage sag.
....and still save a ton of weight and dollars !!


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## GeoMetric (Aug 13, 2010)

Karter2 said:


> Ron, Even if their data is exaggerated 100%, you could still run double the number I suggested ...(6p, 110s ....300a per cell...50C ),...with a lot less voltage sag.
> ....and still save a ton of weight and dollars !!


The problem I have with GEB is their high failure rates, untested cell specs, hand assembly stations, etc....I know the data I get from Jim Hodge (K2 Energy) is 100% legit. K2 Energy cells have been tested by NASA and they currently have many DARPA contracts. Yes, they cost more than GEB, but your quality is much better.


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## GeoMetric (Aug 13, 2010)

Ziggythewiz said:


> Those look like stock photos for an iPadish factory. I'm pretty sure you can't hand assebmble lithium cells no matter how little your hands or pay are.


That is incorrect, most Chinese (not all) factory produce products with high failure rates. Most Chinese factories do not use automation, most of the safety technics used by South Korean, Japanese, American, French, Canadian companies are not used in China. Ask yourself why all these thousands of Chinese battery producers, only have contracts with their own Government or none at all.


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## GeoMetric (Aug 13, 2010)

*Nevada Based K2 Energy Solutions believes Lithium Iron Phosphate Technology may be Solution to Aerospace Battery Problem*



HENDERSON, Nev., Feb. 12, 2013 /PRNewswire/ -- In light of recent scrutiny concerning the safety of lithium ion batteries in the aerospace industry, Nevada-based battery developer and manufacturer K2 Energy Solutions, Inc. (K2 Energy) maintains that not all lithium ion batteries are the same. In fact, there exists an alternative to traditional lithium ion batteries that can be used with improved safety in the aerospace industry. 
(Photo: http://photos.prnewswire.com/prnh/20130212/LA58535) 
As a leading developer and producer of lithium ion batteries, K2 Energy designs a variety of energy storage systems based on its lithium iron phosphate cathode technology. The company's proprietary batteries have undergone extensive testing and analysis, and results suggest a level of safety that is significantly better than other lithium ion battery chemistries.
"It's no secret that any energy storage system, whether it's gasoline, jet fuel, or even lead acid batteries, by nature is hazardous when exposed to certain conditions like a spark, flame, or overcharge. For most companies the logical solution is to simply protect the fuel from exposure," says Johnnie Stoker , Ph.D, CEO of K2 Energy Solutions. "We've taken things a step further by actually changing the nature of the material itself. In the case of our batteries, by physically changing the cathode material we have created an environment where both the likelihood of a hazard, and the severity of an event if one occurs, is reduced."
As to why K2 Energy claims its batteries have a higher degree of safety, company executives point to three key factors: 


Lithium iron phosphate batteries do not experience thermal runaway (the condition currently under examination in the aerospace industry)
Battery packs built with K2 Energy's cells prevent the spread of thermal or venting events.
K2 Energy batteries have a more robust design than typical pouch cell batteries
 *Lithium iron phosphate batteries do not experience thermal runaway (the condition currently under examination in the aerospace industry):*
Thermal runaway by definition is a cascading thermal event that takes place in a battery where a failure and thermal event in a single cell can initiate similar events in adjacent cells. It can be initiated internally or externally to the cell but can ultimately lead to a dangerous, propagating reaction. 
K2 Energy's lithium iron phosphate cathode material, however, does not experience thermal runaway because it does not release oxygen when subjected to high temperatures, over-charge conditions, or mechanical damage as is the case with most oxide-based cathode materials. 
*Battery packs built with K2 Energy cells prevent the spread of any thermal or venting events.*
Understanding the risk associated with creating energy sources, K2 Energy intentionally incorporates proprietary materials, processes and cell designs that reduce the likelihood of unstable thermal events. Strenuous testing and examination has demonstrated that K2 Energy batteries are difficult to ignite because of the materials and cell design used.
*K2 Energy batteries have a more robust design than typical pouch cell batteries*
Pouch cells (batteries packaged in polymer coated aluminum sheets) are used commonly in a variety of industries. However, when they are in close proximity to each other, pouch batteries can be susceptible to damage by thermal events originating in nearby batteries. As a result, a failure in one cell can easily spread, causing neighboring cells to experience thermal runaway, or release chemicals that can contribute to a fire. 
K2 Energy has designed a solution where each battery is packaged in robust steel enclosures, preventing it from being affected by thermal damage from nearby batteries or external sources. 
"Since this company started producing batteries, our priority has been to find and develop new, safer and lower cost forms of energy storage," says Jim Hodge , Ph.D, CTO at K2 Energy Solutions. "We're proud of the headway the company is making and feel we're only in the beginning stages of where this technology can go."
Not only is K2 Energy's effort gaining momentum, it is catching attention. Because of the safety and effectiveness of K2 Energy cells, the company is seeing a steady growing demand for applications requiring the safest batteries available.
A white paper regarding safety can be obtained by contacting the Company at 702-478-3590, or at [email protected]. 
*ABOUT K2 ENERGY SOLUTIONS:
*K2 Energy Solutions, Inc. was founded to commercialize and manufacture rechargeable battery systems for electric vehicles and energy storage applications. The company's battery systems are based on a lithium iron phosphate cathode material whose inherent safety and low cost makes them ideal for the large format systems required for energy storage and EV applications. K2 differentiates itself as a solutions provider for large format battery packs and systems, developing products based upon customer requirements and utilizing expertise in Lithium Iron Phosphate (LFP) battery chemistry.
K2 is a private corporation headquartered in Henderson, Nevada, with manufacturing capabilities in both Nevada and China.
Contact:
Lysle Oliveros, K2 Marketing

K2 Energy Solutions

Phone: 702-478-3590

Email: [email protected]


SOURCE K2 Energy


RELATED LINKS
http://www.k2battery.com


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## Karter2 (Nov 17, 2011)

Have you received your modules yet Ron ?


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## GerhardRP (Nov 17, 2009)

GeoMetric said:


> *Nevada Based K2 Energy Solutions believes Lithium Iron Phosphate Technology may be Solution to Aerospace Battery Problem*
> 
> 
> 
> ...


Odd that he seems to say that K2 invented LiFePO4 batteries.


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## tomofreno (Mar 3, 2009)

GerhardRP said:


> Odd that he seems to say that K2 invented LiFePO4 batteries.


 Yeah, the press release certainly gives that impression, though not expressly stating it. Sounds as if only they produce cells with that chemistry. Never mind it was developed in the early 90's and commercially available cells were fairly widely available in the early 2000's.


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## Genius Pooh (Dec 23, 2011)

Any one know about data sheet for this ???

I try to contact them.. but They don't reply

I need charging data for their cell..

and where is good for sample order?

I specially interest in 26650EV


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## GeoMetric (Aug 13, 2010)

Genius Pooh said:


> Any one know about data sheet for this ???
> 
> I try to contact them.. but They don't reply
> 
> ...


I have some data that might help, please contact me in private so I can give you Jim Hodge's direct email.

http://electricmotorsports.proboards.com/index.cgi?board=6576567&action=display&thread=14&page=2

http://www.nemrs.net/k2energybatteries.html


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