Should WF-139 Get Hot??? Nervous!

[recDNA]

I asked this in another thread but I thought it was important enough to post a new threadin hope of getting a rapid answer.

I'm charging 2 new AW 18650 2600 mA batteries in my new 139 charger.

Batteries arrived at 3.9 volts. After 45 minutes I noticed the charger getting hot at the positive end. The batteries aren't very warm but the charger is. It's about the temp of a hot bath. You can hold it but it is a little warmer than would be comfortable to hold indefinitely.

I shut off the charger and tested the batteries. One is 3.95 volts the other 3.96. Didn't go up much for 45 min but I have no experience to base it on.

Is it safe to continue using this charger as long as the batteries stay only luke warm? I don't know how hot the charger normally should get?

 

[Billy Ram]

Mine gets quite warm. Nothing to worry about.
Billy

 

[recDNA]

Mine gets quite warm. Nothing to worry about.
Billy

Thanks so much for answering. I've been getting up to feel it every 10 minutes for fear it will get too hot.

How long does it take you to charge 2 18650 from 3.7 to 4.2 volts? Is it quicker or cooler to charge them one at a time?

 

[Billy Ram]

It will take about 3hrs to bring them up to 4.19v.
Billy

 

[recDNA]

Thanks.:wave:

 

[alfreddajero]

I dont know about you guys but my charger just gets warm......not hot at all, and i charge rcr's, 14500's, and 18650's. Wish i had a temp gun. Do you keep your charger out in the open like on a shelf or something similar.

 

[recDNA]

I dont know about you guys but my charger just gets warm......not hot at all, and i charge rcr's, 14500's, and 18650's. Wish i had a temp gun. Do you keep your charger out in the open like on a shelf or something similar.

On a glass shelf but it's more the top of the charger that's hot than the bottom. The batteries are only warm. I'd say the temp of the charger is at it's hottest point (on top) about the same as a hot bath.

 

[alfreddajero]

Do you guys have the heat on.....it may be due to the heat rising.....mines in the back room with only one vent.......and the room seems to be always cool even in the hot of summer.

 

[recDNA]

Do you guys have the heat on.....it may be due to the heat rising.....mines in the back room with only one vent.......and the rooms seems to be always cool even in the hot of summer.

It's 72 degrees in the room. The heat hasn't been on all night. The charger is on a nice cool glass shelf. At least it doesn't seem to be getting any hotter and the batteries are warm but not hot. No effective way I can think off to measure the temp of the charger. It's nowhere near hot enough to ignite anything but I certainly won't ever leave it alone. Next time I'll charge one battery instead of 2 to see if it gets less hot or charges faster. The batteries started at 3.9 v and still aren't completely charged after 2 hours. I checked about a half hour ago and they were at 4.02 volts. Maybe takes longer because they are 2600 maH

 

[Linger]

sorry, I say it's a bad sign.
In 12mo I've never experienced it getting warm, nor the cells, and sometimes I've run it on continuous sets of 18650's.

Generally, quick to get to 4.0v, very slow afterwards. I'll check voltage often but if its going above 4.15v, it takes +3 hours.

 

[recDNA]

sorry, I say it's a bad sign.
In 12mo I've never experienced it getting warm, nor the cells, and sometimes I've run it on continuous sets of 18650's.

Generally, quick to get to 4.0v, very slow afterwards. I'll check voltage often but if its going above 4.15v, it takes +3 hours.

I just checked batteries again. Both at 4.19 volts but charger light still red. Batteries weren't even warm when I took them out of charger. Charger is warm. I've surprised the batteries don't get warmer just due to convection from the warm charger.

I plugged it back in. I'm going to give it another 30 min just to see if the charger goes from red to green.

And again a sincere thanks to all for your input!

5 minutes later one side went green then the other about a minute later. Both cells at 4.19 volts. The charger gets hot but seems to do the job. Don't get me wrong. I'm going to continue to keep a close eye on it! I am pleased the batteries never went over 4.19 V. I'm going to check with someone in the lab to see if they have a probe that will measure a surface temp accurately.

 

[alfreddajero]

I would just keep an eye out for it......i have charged depleted cells and the charger and cell does get warm but never on the warmer side.

 

[recDNA]

I would just keep an eye out for it......i have charged depleted cells and the charger and cell does get warm but never on the warmer side.

When I took out the batteries they really were just room temp. Odd. I will mention it to the person I bought it from to see what he thinks. Great service. I ordered on Sunday night and batteries and charger arrived today all the way from Texas. I'm inclined to think it's OK but I am concerned that some say their charger doesn't get very warm. The term "warm" is so subjective. My best description is the temp of a hot bath. It obviously isn't hot enough to damage anything but I don't know if that suggests some sort of wiring problem inside the charger.

 

[alfreddajero]

Please remember that your charging 2600mah cells so it will take time for the charger to charge them up.....that may be why the charger is getting a little on the hot side. You can always get a dedicated charger for 18650's, so this way the other charger will be free for other cells. Or you can charge one cell at a time.

 

[recDNA]

Well it did charge to just the right voltage (4.19 volts). Even though I'm sitting here I have it on a timer set to one hour so if something distracts me the charger will shut off in at most 60 min. It was also a good interval to test voltage.

 

[Mr Happy]

The term "warm" is so subjective. My best description is the temp of a hot bath. It obviously isn't hot enough to damage anything but I don't know if that suggests some sort of wiring problem inside the charger.

I have several chargers that get a little warm from time to time, even my C9000. It is normal for power electronics to get hot in operation. I'd say that as long as the outer body of the charger is not too hot to comfortably touch, and as long as it is not emitting smelly plastic vapors (the best way I can describe overheated plastic), then everything is OK. If it is hotter than that you are right to be suspicious. But don't confuse very warm with hot. For battery chargers to generate heat and get warm is by no means unusual.

 

[alfreddajero]

Mr Happy made a good point because my C9000 gets warmer then the WF. And basically the only cells that i charge with the WF are my 14500's and 16340's.....and i have a dedicated charger for the 18650's. So for me the charger is barely warm....hell im warmer then the charger...lol.

 

[recDNA]

I have several chargers that get a little warm from time to time, even my C9000. It is normal for power electronics to get hot in operation. I'd say that as long as the outer body of the charger is not too hot to comfortably touch, and as long as it is not emitting smelly plastic vapors (the best way I can describe overheated plastic), then everything is OK. If it is hotter than that you are right to be suspicious. But don't confuse very warm with hot. For battery chargers to generate heat and get warm is by no means unusual.

Definitely not hot enough to melt plastic. No smell. Just hotter than I expected. My MG PLI certainly gets hotter than that charger.

 

[alfreddajero]

I would just keep and eye on the charger.....just in case something does happen.

 

[Linger]

hrm, seems my experience is in the minority. Sorry RecDNA.