OK what charger was that ?
2nd sounds like the cell that went 5.27v could have been a good one 
[ from a experimental view ]
really interested in knowing what charger you are using
Me too. Please tell us what charger have you been using.
This is it
Everything on the back is in Chinese except for the words "Multi-function intelligent charger"
What charger is that? :| Brand? Model?
Sometimes it's just the batteries. The Xtar WP2 and the S-- something from KD are both chargers which are reputedly "safe" ones because they err on the safe side (only charge to 4.10 to 4.2v and use proper alg). However, I've had both chargers run questionable cells (salvaged sanyos from a laptop) to red hot temps. This basically means they missed CC termination condition completely and kept pumping current into the cell.
Any chance of a link + did this charger run ok before , or was it just the 4 day run ...
Having a charger that keeps on pushing , = good for experiments or those Samsung 30A ...
All my chargers "supposedly" cut the current when the cells are charged but I still like to take the cells out once the lights turn green. But of course we can all forget, and I have a couple of times. Luckily the chargers did their job and nothing happened.
That cell that went to 5.27V, holy cow, first time I have heard of that.
dang troop i remember a pretty cavalier attitude from you about laptops and l-ion in a thread ..i bet you about wet your pants when you saw 5.27.I would have tiptoed towards the back door with them ... charger too ..is that the ebay charger you bought ?? what kind of batteries ?
Good idea on a timer wilgen ..
I'd toss the entire lot if they weren't hurt before they are now ..I wouldn't trust them for a minute
I think that was the first charger I got with my first light, from Ebay. No idea what kind it is.
Cavalier? Well maybe, I don't worry about Li-On batteries unless they are in use as multiples. I'm surprised the protection in the battery itself did not kick in and stop the overcharge, but maybe because it was plugged in for so long it kept starting the cycle again. Go figure.
You guys think I should try putting the one that registered 5.27v into a light with a direct drive?
LOL, maybe I'll light up the house at the end of the block-or maybe it will light up my house when it goes Ker-Boom? What to you think?
And what do you guess happened to the battery that registers 2.27v and less? Cooked it?
You know, honestly, I'm not totally sure when it was that I plugged those batteries in. Could have been a week ago, not 4 days.
Also, I corrected my OP. These were Ultrafire 3000mAh batteries, red, not Trustfire.
UF3000 are not that great , out of the two I got one died , just plain refused to charge , the other is still going .
Well , 5.27v , now that should boost performance real nice , if you have a light that can handle it ..
I accidentally charge my Samsung 30A to 4.45v instead of 4.35v , no overheating , no voltage sag , in fact it held 4.45 for a week , and then I thought , to heck with it , and I ran it in my SST-50 , I was a little amazed at what a boost 0.1volt gives , another 200 OTF from memory ..
I really think it comes down to individual cell quality , some can - most wont !
You killed one , and the other ? , I know what I would do , but that's me !
I assume that charger charges each side independently of the other. Interesting result. I have a friend who I gave a 18650 light to as a gift. I got him a charger but I am afraid he will leave the batteries in it for days. I lent him a brand new cordless hedger. He left it on charge for a week and cooked the battery. Didn't replace it either and had the gumption to ask me if he could borrow it again. When I told him it was @$#$&% he seemed surprised I hadn't replaced the battery.. Hmm who needs friends like that. But I am afraid he will burn his house down.
old4570- What charger you using to get the Samsungs too 4.35V?
Could i have this problem with the tr003pA4 I ordered?
If so or if i want to be really safe, how much time should i set the timer for empty xtar 2600's?
2600mah/500mah = 5 hours?
I decided to dispose of the two batteries, in fact I put them in a gallon plastic container which I the put in an empty trashcan, just to make sure that if they go off in the 100 degree heat there is nothing flammable around.
It would be interesting to test them in a light, but my concern is that a flashlight is a tightly sealed area, and if the battery vents I don't want to create a pipe bomb...
If it vents in my trash can, not a huge deal. And I have the trashcan sitting inside a big metal wheelbarrow, just in case a battery torches through the side of the plastic.
Isn't there a proper way to dispose of or recycle batteries?
Yes, I'm just trying to keep it in a safe place until I can do that.
Not easy to dispose of, even though Calif is one of the few states that mandates proper disposal of ALL household batteries.
Also, I wanted to let the one that is reading 5.27v 'settle down' for a couple days before I transport that bugger in my car.
In the U.S.: Alltel, Batteries Plus, BellSouth Cellular, Black & Decker, Cingular Wireless, Circuit City, Home Depot, RadioShack, Remington, Sears and Orchard Supply, Target, Wal-Mart and Wireless Zone. And in Canada: Astral Photo Images, Authorized Motorola Dealers, Battery Plus, Bell Mobility, Black's Photography, Canadian Tire, Future Shop, Home Depot, Home Hardware, London Drugs, Makita Factory Service Centers, Personal Edge and Centre du Rasoir, RadioShack Canada, Revy, Telus and Zellers.
Any place that sells batteries like a radio shack , battery plus or a real cellular store
Boaz, you think they will take back batteries of a type that they do not even sell, i.e. Li-on?
there is an e-waste recycling center about a block from where I work, once the batteries calm down I'll bring them both there.
I have to admit, I contemplated dropping the 5.27v one in a big plastic cup filled with water, just to see how it would act when it shorted itself out...
I modified a Soshine SC-S2 , one channel now has adjustable voltage range [ termination ] , only problem is its not stable , has to be re-calibrated every time I use it or it will under charge or overcharge .. Details are over at the other forum ,
I don't think they will short themselves out in water since they are low voltage but it might be worth a try 
You may want to call before you bring them anywhere. I tried taking my recycle batteries to Walmart once and they looked at me like I was crazy, tried taking them to Ace hardware and they said only if they where in packs. However all the target stores I have been to have big bins in the front of the store for recycling, that's where I go now.