Emag Charger and Battery Fun

[Zentish]

I've got a 6 year old emag that wouldn't hold a charge - thinking it was the battery I purchased a 1000mAh replacement battery from KC.

Having let things sit over the winter and worked on other projects I'm now ready to get the marker working again and right away I couldn't get the new or old battery to hold a charge.

I tried charging the new battery several times and it only lasted 20 minutes or so driving only the LED and cycling the solenoid dry a few times.

At this point I'm pretty certain that the issue is the AGD charger. My brother is in to high end electric RC airplanes and loaned me one of his fancy NiMh chargers - a gorgeous unit from great planes called a Triton charger (http://www.electrifly.com/chargers/gpmm3153.html) http://www.electrifly.com/chargers/gpmm3153.html
http://www.electrifly.com/chargers/gpmm3153.jpg

The fancy charger was able to recover both batteries and charge them up after running them through 5 to 7 charge/discharge cycles. It seems to work best set to at 0.4 amps (this sucker runs all the way to 5A),


1) I wanted to share this wonderful charger with the community - it is certainly overkill for the markers but with the readouts and controls you really know where you're at with your battery status.

2) The classic AGD battery shows it taking about 450mAh while the new battery only takes about 320mAh. I'm not surprised over the older battery's condition, but the newer batter is supposed to be 1000mAh. Could the "bad" AGD charger have damaged it?

3) Is 0.4 amps the correct setting four out batteries?

THANKS

[athomas]

That is a nice charger. What is the voltage reading after the battery packs are charged? If the packs aren't functioning, one or more of the cells could be bad. This could happen if the packs were allowed to sit in a discharged condition for a long period of time. Multiple conditioning charge and discharge cycles could eventually fix it. If not, you may have to isolate the bad cell and replace it.

[Ando]

If you have a multimeter you can ck what the mag charger is putting out. Should be in the high 20's. All 3 of mine are between 25-28.

[Zentish]

If you have a multimeter you can ck what the mag charger is putting out. Should be in the high 20's. All 3 of mine are between 25-28.

The charger reads 26v when its LED is red.

The classic battery reads 19.2v fresh after a charge and the charger reports 438mAh.

The newer 1000mAh battery reads 19.6v fresh after a 380mAh charge.

[athomas]

The voltage read seems to be fine. The mAh seems low though. I don't have an answer for that unless the charger isn't completely emptying the cells before the charge.

You might have to take the battery pack apart and discharge/charge each cell individually to get them back in sync.

[gommie404]

I did the same thing bud. and got a 18 cell charger from a RC shop.
there so much better then any thing else out there..