650mAh Ni-MH E-flite batt...

I've been discharging my batts to the point where the main rotors bairly spin in order to set them up on the charger.... I've been charging them for 1hr 15min to avoid overcharging... And I being to conservative? I know the manual states 2.5 hrs for a fully dis-charged batt but I'm paraniod about overcharging them and ruining them... I know I should buy a real dis-charger and charger but I dont want to spend the $$... Has anyone figured out the exact time for a full charge? or should I play it safe and keep doing what I'm doing?

[BLACKHAWK DOWN]

Just Watch It...sit By It If U Have To
Constantly Feel It
If It Burns The Back Of Ur Hand.....it Will Soon Burn More Then That...

hmm thanks... I did read that it was fully charged when it was "warm to the touch" does that mean that if say I always full discahrge it and I happen to charge it in say 2hrs 20mins that it would always charge it in the same amount of time?

[BLACKHAWK DOWN]

NO...OVER TIME THE BATTERY WILL LOSE *FORGET THE NAME* "JUICE" I GUESS
U ONLY CAN CHARGE IT SO MANY TIMES AND IT DECREASES OVER TIME...
YOU SHOULD REALLY BUT A NEW BATT PACK
ID GO WITH LIPO 1000 mAh ITS VERY GOOD AND WORKS VERY WELL WITH THE HOEYBEE WITH A LOTA FLYING TIME SO I WOULDNT EXPECT ANYTHING LESS FOR YOUR BIRD

[Odd_socks]

Hi,

Using Ni-Mh batteries you should have no need to fully discharge them as they do not suffer from the memory effect the the Ni-Cd batteries do.

How long they will take to charge will depend on how much current you are pumping in to them with your charger. If you are charging a 650mAh battery at 650mA this will take aproxamatly 1 hour ( normaly a bit longer due to losses ), at 325mA 2 hours.

The Ni-Cd and Ni-Mh batteries are a bit more tollerant to abuse that the Li-Po batteries so letting them charge till they are warm is fine, but keep your eyes on them. This how we used to charge them with a temperature sensor built in to the charger and the charger would cutoff once a set temperature was reached ( used to be 40 degs C on the Ni-Cd ). This system was droped for the more recent voltage drop system as now and again people would forget to put the temperature probe into the batteries.

Hope this helps,

Tim

I have a 650mah NiMh pack that i want to charge on my delta peak charger however it kicks out 3.5 amps at fast charge...is this too much for the Batt pack??? What is the noraml C rate of charge for one of theese packs??

Cheers,

Damien.

[Odd_socks]

I would not charge them with much more than 0.65A or 1C. This will take about 1 hour.

You might get away with shorter times than this but with these small batteries I would take it easy.

A better idea is to get some more packs. I went out and bought some Ni-Mh cells from maplin ( normal rechargable batteries ) and soldered them in to packs. Three 8.4V 900 mAh packs for £30.

Tim