does this sound normal?
#1
haven't flown in 3 months, and the 1000mah Nicad i have in a plane hasn't been charged in over 2 months (i know, charging once a month should be done).
i went to start a cylce by putting the battery on discharge so i can give it a fresh charge. it only had a 108ma's left.........is it normal for Nicads to drain off like this?
i went to start a cylce by putting the battery on discharge so i can give it a fresh charge. it only had a 108ma's left.........is it normal for Nicads to drain off like this?
#3
thx,
i'm usually anal about anything that i completly forgot to do the once a month cycle on my batteries........for sure it ain't going up tomorrow without being right
i'm usually anal about anything that i completly forgot to do the once a month cycle on my batteries........for sure it ain't going up tomorrow without being right
#6

Nicads will self discharge. Just what they do. I would give them a cycle to make sure they are good. I have more trouble letting batteries sit in planes I rarely fly than the ones that fly every week.
#7

My Feedback: (-1)
sORRY, NORMAL. Depending on the charge at the time you put it away they tend to self discharge quite a bit in a couple of months. I started making up packs with Eneloop batteries to avoid this. The Enelops don't discharge by themselves very fast. Charge once a year when in storage.
#8
Copied from http://www.hangtimes.com/rcbattery_faq.html
"Q: Enh? Charge Retention? What’s up with that?
A: All stored energy systems (batteries) have a ‘self-discharge’ characteristic. This means that a ‘fully charged pack’ is in fact only ‘fully charged’ at the point it comes off the charger in a warm state. Cycling out the pack at that point gives you the nominal ‘capacity’ number for the fully charged pack. If you then re-charge the pack and disconnect it from all devices and let it sit for 2 days and THEN discharge it, it will cycle out with a capacity number up to about 25% below the nominal capacity. More than 25% capacity loss over 48 hours and its possible there’s a weak cell in the pack. Not all battery technologies have the same self-discharge characteristics. As an example, high impedance NiMH Tx packs self discharge at a more rapid rate than Nicads. This is why we always check the voltage display on out Tx’s when we turn them on and we check on- board packs with a load tester before the FIRST flight.. Why?? Well, you may have charged that pack last night… but is it safe to fly now?? Only a load check will reveal if the pack is indeed at a high enough charge state to safely fly it."
"Q: Enh? Charge Retention? What’s up with that?
A: All stored energy systems (batteries) have a ‘self-discharge’ characteristic. This means that a ‘fully charged pack’ is in fact only ‘fully charged’ at the point it comes off the charger in a warm state. Cycling out the pack at that point gives you the nominal ‘capacity’ number for the fully charged pack. If you then re-charge the pack and disconnect it from all devices and let it sit for 2 days and THEN discharge it, it will cycle out with a capacity number up to about 25% below the nominal capacity. More than 25% capacity loss over 48 hours and its possible there’s a weak cell in the pack. Not all battery technologies have the same self-discharge characteristics. As an example, high impedance NiMH Tx packs self discharge at a more rapid rate than Nicads. This is why we always check the voltage display on out Tx’s when we turn them on and we check on- board packs with a load tester before the FIRST flight.. Why?? Well, you may have charged that pack last night… but is it safe to fly now?? Only a load check will reveal if the pack is indeed at a high enough charge state to safely fly it."
#9
Mike... I haven't flown in a while either and ran into the same thing on a 2000mAh NiMh. Doing a little reading and I guess they have a relatively high self-discharge rate. The Sanyo Eneloop cells supposedly don't have this problems. I cycled mine a couple times and it held the rated capacity so I guess it is OK.
Between the rain, the fog and all the crap I have going on right now this is the longest dry spell I've had off from flying in a long time.<br type="_moz" />
Between the rain, the fog and all the crap I have going on right now this is the longest dry spell I've had off from flying in a long time.<br type="_moz" />



