[Genius Pooh]

hi What is real a123 20a pouch's C rate?

They keep change their spec..

I will use battery just for condencer

It's extremely important C rate I will use supercapacitor and battery pack..

My aim is 500~ 1000 hp for 5-10 sec.. battery and capacitor must endure this situation more than 2-3 years... Is it possible?

smaller battery is good for price.. most electronic will obtain by selfgenerator using CNG( natural gas it's extremly cheap in here)

And What is explosion condition?

I hear lifeo is very safe... I suprised volt tester's explosion..

How can I prevent it?

[Ziggythewiz]

A123s do a max of 20C

Supercapacitors really aren't that super.

What explosion condition are you talking about? LiFePo4 does not explode. Most batteries don't explode, actually. The only way for them to explode is to create explosive gases in a confined space, then ignite. Many batteries burn under bad conditions, but that's just burning, not exploding. Nearly everything burns under the right conditions. Don't create those conditions.

Don't overcharge. Don't undercharge. Don't place in proximity to high heat. Don't make a short, or leave in presence of leaking fluids.

[rwaudio]

Originally Posted by Ziggythewiz

A123s do a max of 20C

Supercapacitors really aren't that super.

Agreed!

Originally Posted by Ziggythewiz

What explosion condition are you talking about? LiFePo4 does not explode. Most batteries don't explode, actually. The only way for them to explode is to create explosive gases in a confined space, then ignite. Many batteries burn under bad conditions, but that's just burning, not exploding. Nearly everything burns under the right conditions. Don't create those conditions.

Probably the GM research center that "blew up" while testing an A123 cell. There is no confirmation this is a normal production A123 cell that we could get our hands on, or how far past the limits they were testing it.

Originally Posted by Ziggythewiz

Don't overcharge. Don't undercharge.

I believe you mean Don't Overcharge. Don't OVER DISCHARGE.
As undercharging is completely safe and can be desirable for long cycle life.

[Ziggythewiz]

Yes, thanks. Just play within the specs and you're fine.

[Genius Pooh]

Originally Posted by Ziggythewiz

A123s do a max of 20C

Supercapacitors really aren't that super.

What explosion condition are you talking about? LiFePo4 does not explode. Most batteries don't explode, actually. The only way for them to explode is to create explosive gases in a confined space, then ignite. Many batteries burn under bad conditions, but that's just burning, not exploding. Nearly everything burns under the right conditions. Don't create those conditions.

Don't overcharge. Don't undercharge. Don't place in proximity to high heat. Don't make a short, or leave in presence of leaking fluids.

Oh I see bad normal li sell explode in my front... It's just 2/3 size of 18650 quiet hot ... some plastic is melt down... I think it's not so strong explosion but heat is quiet high... Just I think...

Hm.... A123's data sheet say norminal discharge of pouch.. is 1200w

so they tell nominal rate is 18c .. Am I right??

So I confused Ebay seller said nominal is 3c max is 10c....ah... It's so confusing...

If a123 system answer phone or e mail this problem will be easily solved

[Genius Pooh]

Originally Posted by rwaudio

Agreed!



Probably the GM research center that "blew up" while testing an A123 cell. There is no confirmation this is a normal production A123 cell that we could get our hands on, or how far past the limits they were testing it.



I believe you mean Don't Overcharge. Don't OVER DISCHARGE.
As undercharging is completely safe and can be desirable for long cycle life.

Thank you for kind answer ... We don't have enough power testing limit of A123 system... and even they don't answer me... we need about 10 module the biggest one...

GM's case is very shocking I heard lifo is never explode... I really wonder what happend...

And I wrote above A123's spec is very confuse I wonder everybody in this site well doing with a123's pouch... I saw everybody to use it...

[Ziggythewiz]

A123 does not sell to DIYers. You can't contact them and say qreqwrwer on ebay sold me your cells, what are the specs on them?

There are some people here using A123 pouches, certainly not everybody. There are much fewer due to the complexity of assembling a pack. I don't know if there's anyone even running a full A123 pack in a street car. I know people are building them, but not sure if any are complete.

[rwaudio]

Mavizen is the only authorized distributor that I'm aware of and they quote the following:
Maximal current discharge rate: 300 cont, 750 peak

Which is 15C continuous and 37.5C peak

[Jozzer]

You will find for anything above 8-10C continuous you will need serious cooling and a very well built pack with decent interconnects that can take heat from the tabs..

[Genius Pooh]

Originally Posted by Jozzer

You will find for anything above 8-10C continuous you will need serious cooling and a very well built pack with decent interconnects that can take heat from the tabs..

Thank you I will try to use A123's module..42p3s ..

It will need another cool solution ?

Or I must reassemble it??