LiPO Flight times decreasing

[jsclmn]

I've noticed that after many charge/discharge cycles my flight times are decreasing. One of my 2x1200 Kokams that once gave me about 16-18 minutes now gives me about 8 minutes. I've checked the balance charged/discharged and that looks OK. IS this normal over a many charge cycles? Is there a point at which the batteries should not be used?

thanks.

john

[davidcollins001]

Have you looked for other sources for the diminishing flight times? My flight times were way down, I cleaned my motor and I had loads more time in the batteries - only trouble is that on the flight I knackered the Rx, and now I have just found out the gyro too [img]/ubbthreads/images/graemlins/frown.gif[/img] [img]/ubbthreads/images/graemlins/frown.gif[/img]

[jsclmn]

I have two LiPO's one is still giving me about 15-17 minutes while the other battery gives me about 8 minutes. I'm assuming like all rechargable batteries with each charge they loose a little capacity. I wondering what's safe and when to pitch them.

thanks,

john

[pgoelz]

Both my original Kokam 1020s are essentially dead after about 1.5 years of use. They were used primarily in the Piccolo at about 2.2A but in the later months were also flown in my IFO that draws about 3-4A in a hover or full throttle climbout. That may have damaged them.

They have been replaced by a couple E-Tech 1200 packs. We'll see how long those last.

I am also "flying" three Kokam 3000 mAH cells in my IBM Thinkpad 600 laptop that seem to be OK after about 1.5 years. However, those cells sit fully charged and are actually seldom used to power the laptop.