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Electric Stunt => Gettin all AMP'ed up! => Topic started by: frank carlisle on November 23, 2006, 03:06:58 PM

Title: battery state of charge
Post by: frank carlisle on November 23, 2006, 03:06:58 PM
I took the electric Smoothie out to fly today. It had been nearly two months since the last time I'd taken it out. I charged the batteries when I put it away.
Today when I took the plane out the motor ran for only about 20 seconds. I tried the second battery and the same thing happened.
SO......I took it all home and charged the batteries then took the Smoothie back out. This time everything worked right.

So I guess if it's been a while you should charge the batteries before using them. If this is the case - it makes sense then that you would charge li-po batteris every so often rather than store them with no charging.
Title: Re: battery state of charge
Post by: linheart smith on November 24, 2006, 07:55:56 AM
I let a battery drain to very low voltage by leaving it connected to the ESC  over night. 

That battery swelled up to 125% of it's original size.  $140.00 down the drain.

Based on what you said, I better plan on charging  my batteries regularly during the off season.

Linheart


Title: Re: battery state of charge
Post by: frank carlisle on November 24, 2006, 08:43:12 AM
I don't know for sure what the protocal is about charging li-pos occasionally but during the off season  I plan on getting mine out and doing just that.
Interestingly,when I took them home for a charge the bats only took a 17 minute charge. I didn't check to see how many amps they took on but it couldn't have been many.
I'm going to take the plane out again today.

Incidentally, I burned out my charge gard. I think because I disconnected the battery but probably should have gotten the clips off the car battery first.
Title: Re: battery state of charge
Post by: jfv on November 27, 2006, 09:04:05 AM
Most manufacturers recommend storing li-po's for extended periods at about 1/2 charge.  That's about 11.2 volts for a 3 cell pack or 15 volts for a 4 cell pack.  Shouldn't really be a need to periodically charge them, just check the voltage now and then.