Not really a beginner post but new modeler should know and could gain from some of the responses.
This weekend I was all set to participate in a contest. I charged my rx battery (hydrimax NiMH 1600m, 4.8V) for 11 hours at 0.2A Thursday night. It ended then trickle charged. My TritonEQ charger put 840ma in the battery. When I got to the contest field Friday, I did a range check, then I checked my battery again. 4.44 volts
So I hooked it up to my quick charger run off of my 12V car battery set at 0.6A. After an hour, I discovered I had a frayed negative charge lead
I borrowed another pair of leads and charged it at 0.6 for another hour and a half. Still 4.44 volts. Did not fly.
When I got home, I put on a new out of package battery I purchased in Feb that I was going to use for another model. 2000ma 4.8V NiMH., charged at 0.2A for 13 hours. The next morning it had put 1730ma in, but when I check with my meter it was 4.56V. No fly for me.
I put the 1600ma battery on tritoneq charger again, 0.2A, completed charge and meter read 4.67 volts, still not flight worthy.
I either have extremely bad luck with batteries, a bad charger, or a bad meter.
I have some trusty old nicad 4.8V 700ma n charger now. If they don't charge I'll have my answer. They did read 4.9 on the meter.
Battery 1 was about 4 years old Had 8 discharge cycles on it and was always charged at either 0.2A at home or 0.6A at the field. Battery two was 4 months old but never used.
I guess my point is, check your batteries often. I would have lost my favorite model if I had tried "just one flight" on these packs. Don't risk your model, yourself, others. If you have a doubt about your batteries, don't fly. Not worth it. Dumb thumbing a model is one thing, a preventable mishap shouldn't happen.