AA battery question - M11 TX with 2300s

[elite]

So I got myself a new M11 a little bit ago - along with some racer edge (I think) 2300 nimih rechargable batteries. I reset the timer on the radio evey time I charge (so I can see how long my batteries last). Im getting about 8-9 hours per charge. I usally recharge when I get voltage readings at around 9.4ish (the radio will beep at you if goes to low anyhow). When fully charged I get about 11.0 volts. What Id like to know is - since I charge them together in the battery tray how do I know if I ever have a bad cell? Reason I am asking is when I plug my battery pack in its tray in my charger it typically detects the ammount of cells. It reads 7 cells, not 8. So - Im thinking its possibly that 1 of the AAs is bad. Its not the money - but its more WHAT 1 of the 8 cells is bad. Lastly - its possible that the charger just doesnt correctly detect the cell count......thats totally possibly. Using a super brain 977. Seems somewhat accurate though - havent had any trouble with it and it detecs most pack cell counts correctly. Any idea on how to test, or thoughs at all?

[Duster_360]

Bad cell should be identifiable using a voltmeter of some kind - right after a charge, check them individually to see which one is off the voltage indicated by the rest. The bad one will read less than the others. Also, bad cell will usually get hotter than the rest when they charge.

Though at 11v with them charged, I don't think you have an AA prob - that would be 1.38v/cell, about what would be expected with a good batt right off charge. If there was a bad one, it would mean the 7 good ones were at 1.57v. I don't think you can get a NiMh to make that kind of voltage. I have a Futaba 3PK and use a pac built from 8 2300 Sanyo NiMh AAs. I typically see 10.8 - 11.1 when its freshly charged and I'm pretty sure there's nothing wrong with my pac.

I think your charger is just not arriving at the right cell count for some reason. Have you tried discharging before you start charging? Maybe charging starting at 9.4v has something to do with it getting wrong cell count?? I don't discharge after every use, but do discharge every 3rd or 4th time.

[elite]

Thank you for that...maybe all is well. Ill get a volt meter like you suggested and test em out....thanks again!

[Duster_360]

I think tht is what you're going to find - your AAs are ok.

It may be kind of a so what figuring out what's going on with your charger since it looks like its charging them alright based on the voltage you're seeing.