lifeP04 48v 20Ah compare - Cammy Vs Ping

[dogman dan]

Well There's yer problem! As the mythbuster would say.

Sadly, that is about all you can expect out of those cells. She may be buying them from you know wu. I'd say treat em real gently or RIP. And another potential seller we can trust definitely bites the dust. I really was hoping she would prove out with good enough product to have a second chance. I'm sure a pack from those cells can be made and used for some time, but it just isn't going to compare with what Ping sells. Just like Pings cells can't compare with A123 or others that perform better.

 

[dogman dan]

Sorry if my tone in the last post rubs you wrong Fredo, I'm sure its NOT amusing at all to you.

As a practical matter, your pack may be improvable if you can figure out which cells are duds. Even if the pack was not made from the old dumpster cells that we have been warned are circulating out there, it may just be made of really mismached cells, or just has a few just plain bad ones that could be hunted down and replaced. It will be a big pain for you to fix this, but you may have a few bad cells drag down all the others in the pack if you don't look for them.

If you keep riding, I'd keep depth of discharge well under 50%

 

[Pete]

Is there any easy way to find dud cells in a parallel group, without unpicking everything ?

The only option I can see is , at best, find the bad parallel groups and cut them out, break them up and test each cell. Then weld it all back together with new tabs.
and at worst, having to disassemble the entire pack before rebuilding it with known god cells. Ouch.

What an unbelievable PITA. Now I see why Ping won't touch 18650's. I guess the concept is great in theory but only practical if you are building with reliable, robust A123's.

It sux bad enough needing to replace a 4P group in a ping pack, I am glad it uses soldered tabs on a bus bar.

 

[Fredo]

Cammy proposed my to refund my pack if after 30 cycles, I do not get the claimed 12Ah.
So I am going to return the battery probably as I prefer to spend $80 to return the pack than trying to fix something which is lousy anyway.

 

[dogman dan]

Good for her! And you! I hope she can get a supply of more reliable type cells in the future. I'm sooo unimpressed with the round cells.

 

[solarbbq2003]

i think there is a way you can find a dud cell, I've noticed with cobalt type that a cell on the way out , its temperature is higher than surrounding cells, I keep an eye on the cells just feel them every so often, if I can feel some warmth I know there is a problem, but the duds either when using during a ride or when charging temperature is different.
Problem is you need to be able to feel the cells with your hand is very easy way to find teh bad ones