eFest Battery problem..

[dudeitsmattx]

I have two eFest 18490 that I got new from a local shop. I have had them about 1-2 weeks with no problem. Put them both on the charger since they were dead but the light stayed green as if there was no battery on it or it was full. When I put it in my zmax it wont even power it, does the same when I put it on a mech. I have never got eFest brand untill these, is this common?

 

[mackman]

Well off the top of my head I might suspect that you drained them so low the charger can't charge them.

 

[retrox]

Check those batts on a multimeter. You should be able to pick one up on the cheap at your local Lowe's / Home Depot /etc. Simply put, you absolutely NEED one if you're running unprotected IMR's in a mech. Sounds unlikely that both would die at once, though. Have you ruled out the possibility of a faulty charger?

I've found the quality of Efest cells to be inconsistent, but I've never had them just suddenly refuse to take a charge. I personally don't bother with them anymore. They're cheaper, but they don't last nearly as long as my AW's, Panasonics, or MNKE's.

 

[Baditude]

Check those batts on a multimeter. You should be able to pick one up on the cheap at your local Lowe's / Home Depot /etc. Simply put, you absolutely NEED one if you're running unprotected IMR's in a mech. Sounds unlikely that both would die at once, though. Have you ruled out the possibility of a faulty charger?

I've found the quality of Efest cells to be inconsistent, but I've never had them just suddenly refuse to take a charge. I personally don't bother with them anymore. They're cheaper, but they don't last nearly as long as my AW's, Panasonics, or MNKE's.

Same experience here. I've experience with 14500 & 18350 Efest IMR's; they were fine for a couple of weeks and then they dropped off their capacity by nearly 50%. They're now in a drawer in case of the Zombie Apocolypse. The brand seems to be inconsistant, and I'll never purchase more. Only AW or maybe Panasonic from here on out.

 

[dudeitsmattx]

Yeah I tried my other charger same thing. Also put my Sony that was half dead on the chargers and it started charging just fine. Maybe when I last charged them I left them on to long?

 

[Baditude]

Yeah I tried my other charger same thing. Also put my Sony that was half dead on the chargers and it started charging just fine. Maybe when I last charged them I left them on to long?

Well, theoretically batteries should be removed from the charger as soon as they reach full charge. That's why people say don't leave batteries charging overnight while you are sleeping or when you leave the house. The better quality chargers stop charging at full charge, but its still best to remove them.

Some of the very best chargers can revive dead cells if they are not too far discharged. I believe the Xtar VP1 can do this.

What chargers do you have?

 

[dudeitsmattx]

One is a crap no name that came with a K100 kit I got awhile ago. But I also have a TrueFire that I got for $18 at a local shop.

 

[Baditude]

One is a crap no name that came with a K100 kit I got awhile ago. But I also have a TrueFire that I got for $18 at a local shop.

Neither are recognised as a quality charger. Pila, Xtar, and Nitecore Intellicharger are the top manufacturers. Battery chargers at RTD Vapor

As a general rule ignore any battery or charger with "fire" in the name.

 

[fabricator4]

I have two eFest 18490 that I got new from a local shop. I have had them about 1-2 weeks with no problem. Put them both on the charger since they were dead but the light stayed green as if there was no battery on it or it was full. When I put it in my zmax it wont even power it, does the same when I put it on a mech. I have never got eFest brand untill these, is this common?

It sounds like you possibly discharged them too far, which is normally only possible on a mechanical. Check the batteries with a multimeter and see what voltage they are at. If using them on a mechanical you really must keep track of the voltage and preferably not let them drop below 3.2v. I prefer to charge batteries before they hit 3.5V as it will prolong their life.

You might be able to boost charge them to bring them back up to a level where the charger will recognise them. Put them on a 4V power source in charge configuration for about 30 seconds, then put them on the charger. It's generally safe to do this.

If you use the Zmax you don't really need to worry about any of this because it will turn off when it reaches a low voltage, normally 3.2V under load.

I've got four or five IMR Efest batteries and find them great - the capacity of ones I bought six months ago are still about the same as ones that I bought in the last 6 weeks - and in all cases is over the rated capacity claimed for the batteries.

 

[dudeitsmattx]

Well that's the thing I only use the efest's on my zmax.I use the Sony for my mech cuz its sub ohm.. So like this charger would be a good one?http://bevapehappy.com/shop/nitecore-intellicharger-i2-smart-charger/