Concerned About my Tenergy AAAs

Just got done recharging my 4 AAA Tenergy batteries which have performs nicely thus far. Only I went to get them off the charger (Intellicharger, of course) and those in all 4 bays were somewhat warm. Not hot, mind you, just noticeably warm. Is this a problem or sign of anything?

Warm = Charge rate may be a tad high !

See near the end of HKJ's review thread on that charger. There are posts of issues with AAA's in it getting hot and over-charging. (Sorry, on my phone and tough to get you a link.)


Is Tenergy the same as Turnigy?

I was charging a set of 4 eneloop AAs and then a set of 4 Turnigy AA LSD 2400mah in the intellicharger and the Turnigy ones are noticeably hotter when done.
I also charged the 2 sets in eneloop m06 charger and the turnigy ones are still noticeably hotter.
Since they are AAs, I think some brands will just be hotter when charging?
Or is it because the eneloops has vents at the top so they are cooler as the turnigy ones do not have visible vents?

I wonder if there isn’t something “different” about Tenergy AAA batteries. When I put 12 brand new Tenergy Centura (supposedly pre-charged LSD) batteries into a brand new Tenergy 12 position TN160 charger:

1) Five of them terminated in about two hours after getting warmer than I’m used to with my other NiMH AAA batteries and chargers and I thought this was a little long for an initial charge on supposedly fresh LSD type batteries.

2) Seven of them had NOT terminated after four hours and were extremely hot (I removed and rested them overnight, and they tested 100% on a ZTS).

I’ve subsequently used all those batteries for several cycles, charging them in my MAHA chargers instead, and although they do seem to get warmer than my AAA Eneloops , they don’t get as excessively hot as they did in the Tenergy TN160 charger on the first charge cycle, and the seven “hotties” don’t seem any the worse for wear at this point. I returned the Tenergy TN160 charger for a refund as I figured it was the culprit and didn’t trust it any more.

Now after hearing about other people’s problems I’m wondering whether there’s something about the chemistry of Tenergy AAA batteries in particular that challenges the endpoint detection circuits/algorithms of some chargers (including Tenergy’s own). I also use quite a few Tenergy “original blue”, Centura (LSD) and Premium batteries in AA, C and D sizes and have never had a problem with them getting too hot or not terminating in a reasonable amount of time in any of the chargers I’ve put them in (mostly various MAHA and Energerizer “Family” models).

I have an 8 bay "smart charger" (Tenergy by the way) and I charge my AA & AAA Eneloops in it. They get hot as heck, but only if they have been discharged quite low. So hot that I don't want to pick them up till they cool. This has been going on for three years now and the Eneloops still seem to be fine. They charge to 1.4-1.5 volts in that charger.

I had some Tenergy AA & AAA. (Edit: Bought straight from the Tenergy site, all-battery), I got rid of them. They went bad quickly and they got even hotter than the Eneloops. I don't care for Tenergy cells. I have tried AAA, AA, C, D and Sub-C from them. Not consistent and don't get all that many charges out of them. I think the Tenergy AA & AAA must have had high resistance and that might account for getting hotter in the same charger.

Not sure if its your batteries, Rusty, or the charger, but here are those posts garrybunk was talking about:

Did you buy your Tenergy’s from Mars,Inc from Ebay?

Lots of people have the same problem with tenergy cells, me also, I have a MAHA C800 and my eneloops and other nimh AAA and AA charge nicely, never even get warm. My tenergy batteries get hot as hell and almost too hot to handle. They never show full, but they are.

about three years ago Battery Junction had a fire. everything got hosed down with water. MarsInc bought a HUGE lots of nimh and Li-Ion and all kinds of other stuff at dirt cheap. Tons of people had these same problems with batteries purchased from that lot, or that came from that fire. I bought 24 AAA and 24 AA Tenergy nimh for dirt cheap from mars inc. I tested them and half of them were DOA or wouldnt charge up all the way and got super duper hot. Mars Inc quickly replaced them. Half of the replacements had the same problem - however I didnt make him send me more replacements. At that point, I payed so little for them in the first place that I felt I had gotten what I payed for and MarsInc tried their best to fix my problem fast.

Im pretty sure there are still some of those tenergy’s floating around to this day being sold. And I think we all got the FireSale Batteries. Just my two cents.

> three years ago Battery Junction had a fire …
> Tons of people had these same problems with batteries purchased from that lot, or that came from that fire.

Aha. I got taken by that too — I bought bad lots of the Tenergy NiMH D cells and AAA cells from two different resellers in the last year or so, and I know there are lots of them still out there for sale real cheap.

None of the cells were very good and half of them failed almost immediately.

Light blue wrapper with the lower case “e” on it.

Damn. Good to know what happened, wish the word had been gotten out early enough to know.

I’ve found that the Tenergy batteries can be hit or miss, but generally tend to be on the good side. I think it really just depends on the luck of the draw.
I’ve had good experiences with their chargers so far, they have great variety and I haven’t had any problems to date.
@ Rusty Joe, I don’t think that the batteries coming out slightly warm is anything to worry about, I have found that happen occasionally myself. What I would recommend, however, is making sure that you keep an eye on them and definitely don’t ever charge batteries when you are not at home, or better yet, in the room just in case something does happen to go wrong.