Heavy discharge test ..2200 Amps !

[Hillhater]

You mad scientists will like this "Irish" cell tester pulling 2200amps from a single cell
Skip the EVTV stuff to the 1hr 03 point where the fun starts ! :lol:
http://www.youtube.com/watch?v=ZUOuInwMXyo

 

[ohzee]

That was pretty impressive.

 

[mdd0127]

These may be really stupid questions but here goes.....

How much would a 3.5v to 50v dc to dc boost converter capable of 150A peak and 75a continuous weigh?
Is there such a thing already?
If not, how hard would it be to build?

I really like the idea of having one of these CALB CA180fi cells for a battery pack. 12ishAH at 50v right?, 12lbs, $265......

or

 

[SamTexas]

That was a 180Ah cell right? So that's only 12.2C.

A123 26650 can do much better that.

 

[Chalo]

I remember witnessing a 2400A discharge from a flywheel energy storage machine I worked on... but that was at 500V. The juice made a bundle of 1000MCM (huge fat heavy) cables repel each other and fall out of the ladder tray that was holding them.

 

[Farfle]

I remember witnessing a 2400A discharge from a flywheel energy storage machine I worked on... but that was at 500V. The juice made a bundle of 1000MCM (huge fat heavy) cables repel each other and fall out of the ladder tray that was holding them.

That's impressive, 1000 mcm is aah biiiig cable. We have some scraps here at the shop that came off of a locomotive. With jacket its like 2" around. The conductor itself has got to be bigger than one inch dia.

 

[Hillhater]

That was a 180Ah cell right? So that's only 12.2C.

A123 26650 can do much better that.

Yes and Nanotek Turnigy even better still...

.... not from a single cell tho'..
... but "C" rate is not the point...Its the way it was done and the actual Amp level dealt with using some very basic discharge kit.
Didnt you like the idea of different size wrenches for different discharge rates ? :lol:
In fact, someone has stated that that cell could discharge 6000+ amps on a dead short

 

[Chalo]

I remember witnessing a 2400A discharge from a flywheel energy storage machine I worked on... but that was at 500V. The juice made a bundle of 1000MCM (huge fat heavy) cables repel each other and fall out of the ladder tray that was holding them.

That's impressive, 1000 mcm is aah biiiig cable. We have some scraps here at the shop that came off of a locomotive. With jacket its like 2" around. The conductor itself has got to be bigger than one inch dia.

They were about 1-1/2" diameter or so with the jackets, so maybe 500 MCM cable then. Still it was a pile of cords bigger and heavier that I would carry at one time squirming around like it was alive. Eerie.

2000+ amps is a stupendous amount of juice to be able to pull out of a 12 pound cell. I would like a battery that performed like that on a power-to-weight basis (safely). That would be like 200A from a 39.6V battery weighing 12 pounds.

 

[Holocene]

That video was like listening to the Hindenburg burn on the radio -- too bad you can't see any action.
:|

Cheers, and keep Grinning!

 

[circuit]

not these rednecks again..

 

[bigmoose]

It was sort of kewl seeing your spanners calibrated as current shunts.

 

[EVDragRacer]

You mad scientists will like this "Irish" cell tester pulling 2200amps from a single cell
Skip the EVTV stuff to the 1hr 03 point where the fun starts ! :lol:
http://www.youtube.com/watch?v=ZUOuInwMXyo

They are impressive cells, but the weight at 12lbs each is twice as heavy as:

K2 Energy Cells

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

For 1800A sag = 2.3V
2500A sag = 2.0V
3000A sag = 1.6V
http://electricmotorsports.proboards.com/index.cgi?board=6576567&action=display&thread=14&page=2#ixzz2JKFbE72t
http://www.nemrs.net/k2energybatteries.html

 

[Hillhater]

They are impressive cells, but the weight at 12lbs each is twice as heavy as:

K2 Energy Cells

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

Err,...it maybe twice as heavy Ron, but its also 2.5 times the Ahr capacity !

You of all people Ron, might take note of how to do your own heavy discharge tests before you assemble another mega pack based on someone else's data ! :wink:

 

[EVDragRacer]

They are impressive cells, but the weight at 12lbs each is twice as heavy as:

K2 Energy Cells

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

Err,...it maybe twice as heavy Ron, but its also 2.5 times the Ahr capacity !

You of all people Ron, might take note of how to do your own heavy discharge tests before you assemble another mega pack based on someone else's data ! :wink:

The data supplied by K2 Energy has been verified by many third party testers, including Elithion. In regards to twice the AH you can parallel two 73AH K2 modules and create the same weight, same AH, but the K2 Energy modules would have twice the power! Calbs do not match-up to K2 Energy.

 

[Hillhater]

The data supplied by K2 Energy has been verified by many third party testers, including Elithion. In regards to twice the AH you can parallel two 73AH K2 modules and create the same weight, same AH, but the K2 Energy modules would have twice the power! Calbs do not match-up to K2 Energy.

There is no substitute for first hand test data. !
Oh ! , and when you have bought those 2 K2 modules ( for 150Ahr only and weighing 13+ lbs !)..how much would they have cost compared to the 180 Ahr CALB ??
Hint : more than TWICE the cost !

 

[EVDragRacer]

The data supplied by K2 Energy has been verified by many third party testers, including Elithion. In regards to twice the AH you can parallel two 73AH K2 modules and create the same weight, same AH, but the K2 Energy modules would have twice the power! Calbs do not match-up to K2 Energy.

There is no substitute for first hand test data. !
Oh ! , and when you have bought those 2 K2 modules ( for 150Ahr only and weighing 13+ lbs !)..how much would they have cost compared to the 180 Ahr CALB ??
Hint : more than TWICE the cost !

If you want maximum torque/ HP the K2 Energy Power Modules cannot be beat, even at 73AH the density is not bad. You will never match K2 Energy Power Module's power with any Calb unless you run them in parallel, but if its density you wish for than there is even cheaper cells than Calb. The benefit of K2 Energy Solutions is their ability and willingness to sell single cylindrical cells and build custom packs.

 

[Hillhater]

Ron,
most EV builders dont even need the 2000 A the Calb's will supply..
..But ,..they do need the Ahr capacity for maximum range,
..and they dont want the expense of a high output battery that they will never use !
so, sure K2's win on power,.. ( Vs the Calb) ..but they lose big time on cost ( 2.5 times the $$$'s)
And if you really want a high power to weight ratio from your cells, ..there are better ones than K2 available.

 

[EVDragRacer]

Ron,
most EV builders dont even need the 2000 A the Calb's will supply..
..But ,..they do need the Ahr capacity for maximum range,
..and they dont want the expense of a high output battery that they will never use !
so, sure K2's win on power,.. ( Vs the Calb) ..but they lose big time on cost ( 2.5 times the $$$'s)
And if you really want a high power to weight ratio from your cells, ..there are better ones than K2 available.

I'm sorry, but I would have to disagree. The market for safe chemistry high power cell modules is growing daily. And K2 cells are not 2.5 times the $$$. Can you build a 10P 24S small module from Calb? No, but K2 Energy cells match the A123 M1 cells and can be built in any configuration.

 

[Hillhater]

CALB CA180 cells are <$250 for single cell, = $1.38/Ahr,... and much cheaper in quantity
http://www.evsource.com/tls_lithium_calb.php
K2 LFP 73 Ahr are $350, so thats $700 for 146Ahr, = $4.8 /Ahr
http://store.peakbattery.com/k2lfp90ahr.html
..BUT.. better value is the K2 90Ahr "Energy" cell at only $315 each..or $630 for 180Ahr, = $3.5/Ahr !
http://store.peakbattery.com/k2lfp903enba.html

Unless my maths is wrong...or you can show a cheaper source Ron, 630 / 250 = 2.5 times the cost.!

Why would i want to build a 10p, 24s pack.. ( 77v, 1800 Ahr ??) .. of calb cells anyway ?

 

[Farfle]

CALB CA180 cells are <$250 for single cell, = $1.38/Ahr,... and much cheaper in quantity
http://www.evsource.com/tls_lithium_calb.php
K2 LFP 73 Ahr are $350, so thats $700 for 146Ahr, = $4.8 /Ahr
http://store.peakbattery.com/k2lfp90ahr.html
..BUT.. better value is the K2 90Ahr "Energy" cell at only $315 each..or $630 for 180Ahr, = $3.5/Ahr !
http://store.peakbattery.com/k2lfp903enba.html

Unless my maths is wrong...or you can show a cheaper source Ron, 630 / 250 = 2.5 times the cost.!

Why would i want to build a 10p, 24s pack.. ( 77v, 1800 Ahr ??) .. of calb cells anyway ?

I think he means a 10p24s pack of the lil k2s for an ebike application.


Both of these cells have their place, the Calb is probably more sensible for the masses. But for somebody looking for a performance cell who doesn't need to drag around the extra pounds of calb cell to get the discharge they want, the k2s are a pretty kickass setup as far as a preassembled large format High C rate pack.

 

[liveforphysics]

Both of these cells have their place, the Calb is probably more sensible for the masses. But for somebody looking for a performance cell who doesn't need to drag around the extra pounds of calb cell to get the discharge they want, the k2s are a pretty kickass setup as far as a preassembled large format High C rate pack.

That is a perfect assessment Farfle, well done. They do both have a place, most things have a place. Once in a while something is just utter garbage, but most things have a place.