Charging AA NiMH cells problem
 

Hi all,
I bought some protek NiMH AA cells for my DX3R and have been having problems charging them
Have never been able to charge them and am wondering if I'm doing something wrong. I've tried several ways, I tried charging them inside the radio using my DuraTrax ICE charger, but I get an error saying "Output voltage is higher than the selected cells". I'm trying to charge 4 of the AA sized batteries, they're 2500mAh cells. I set the charger to NiMH 4cell 2500mAh and get this error. I tried removing the cells from the radio and charging them in a battery holder, get same error. I discharge the cells then tried charging but get the same error.
I tried charging the cells with my intellipeak charger, but it gives some sort of error blinking all the lights. Anyone know what I could be doing wrong? Thanks

just let them trickle on the charger... works like a charm for me. On my intellipeak, i'd set it to a 1 amp charge for my 2400 mah AA batteries. I know its slow, but it beats letting them charge at 50-100 mah an hour with a wall charger.

I had the same problem trying to charge my m11 thru the charge cord on my much more cell master last night set at 2500mah cap. and 2.5 amp charge, i think the voltage needed to try to charge the cells at that high of a setting requires more voltage than my power supply was able to put out, so i used the same charge cord and hooked it up to my hobbico quick field charger mkII pro series that i use for my lipo in my 18r and my gliders, set it to its max amp setting and set it to nimh and had no problems at all, i did stop the charge a little early because the cells were getting a little warm.
If i were you i would try turning down the amperage between 1-2 amps and see if that helps.

What is your current setting? If I go much about 0.5~1 amp my ICEs will overvolt too. Too much for a regular AA radio battery anyway. Not a big deal really because DX3Rs run a long time on batteries. :)

I'll go try low Amp setting now on my charger, I was using 1.2A as the battery recommended charging at 1/2C which I think is 1.25A? I'll put it way down and see what happens, thanks for the advice, especially if it works :)

Ah weird, I have it at 3.6A some reason, must be why it wasn't working! I changed it now to 1.2A and so far it's working nicely :) Yay!

AA NiMh
 

Be careful charging those little AA cells at more than 1amp.. even that is a bit much.. They can't handle too much heat and may burst!

I would never use my fast charger through the radio.. I have known too many folks over the years that have goofed or had cells pop in their radios and meltdown.

Go down to Radio Shack and get a battery holder for it and charge it in there.

All in all.. I've gone back to just using Alkaline batteries.. 2 packs at the 99 Cents Store seem to last just as long as Duracells for $8. They also have higher voltage than NiMh. I didn't like to have to charge my NiMh before every race night.. they don't hold a charge if they sit over time...

The LiPo packs I've seen around for radios seem to be doing pretty good.. just a bit pricey..


Good luck!

Jerome :tire::tire:

I only charge mine at 0.5 amps and it takes a little longer but they charge up nicely. I have sixteen of them so I just keep eight fully charged during races as a backup.

He shoots...he scores! Yep, 0.5 amps out of the radio, or just use alkies.

Some radios have a built in diode that restricts charge rate thru the radio to very low currents. Futaba 3PM has a diode that will not allow any higher charge rate than the output of their purpose built wall charger which is less than 100ma, I think 70ma. You could try a veryu low rate and see if that works - its not very timely though.

You're going to have to pull batts out of tx to charge at higher rates. I use a lot of AAs for my digicam and rates above 1amp are not recommended for AAs. The 1C rule does not apply to AAs - charging 2500s at 2.5a will def lead to shortened life! I use a professional level AA and AAA recharger made by Powerex and it uses 1amp as a fast charge, 0.5 as a slow charge and 50ma as a trickle. Their advice is to slow charge as much as you can and only fast charge when you have to.

I started using lipo in my tx and so far really like it.

I run LiPos in my car and like them, is there a LiPo pack that will fit the DX3R?

Not really, the voltages don't match up, would need to use a voltage regulator.

I know what you are saying, lipos are way cool, but fortunately it not a big deal with a DX3R. Its already really light and the batteries last a long time. I have cheap 2600 nimhs, have only charged them twice since March, both times mostly out of guilt, they were still going strong. Racing 2 classes weekly plus some bashing.

Alright so is 1amp really too much for AA nimh? I dont know dirt about this electronic stuff, and ive had my brand new 5 AA cell 2500mah stikman Rx pack charging at 1amp for about 15 minutes and I about fell about of my chair trying to unplug it fast when I read that 1amp is too much for these cells. Whats the truth? I hate this electronic crap! :flaming: give me an injected big block chevy to dial in or something :nod:

http://i19.photobucket.com/albums/b1...7/DSC06941.jpg

battery and my charger

Bump^ Would love an answer to my post above. For some reason I always recall charging my Tx packs, which are AA sized cells at around 3 amps, for a long time without having a problem, was I just lucky for a very long time that I didnt set off the battery bomb? I'd really like some reassurance so I can break my buggy in :sweat: