Greenie

I ran a 2 cel Li-Po down to 5.71 volts before I stopped. Also, it was several hours before I got it onto a charger. What kind of damage (if any) did I do and what does the damage (if any) mean?

When I put it on the charger, the charger just beeped at me until I set it onto the 1 cel setting even though there was a 2 cel battery in it. I was able to switch it to the 2 cel setting after a few minutes and it is now charging fine. Anyone know why?

Thanks!

powerlines

I have ONCE!!!! charged it on NIMH setting at 1C. for 10 min while WATCHING IT LIKE A HAWK!! Then took it off and let it sit for 15 min and then charged it normal and I still run it today...

LATER
I have run mine down a few times... LOL

Greenie

I am new to the hobby and I do not know much about Li-Po's (obviously). I have been told that running them below the 3.2 V per cel damages the batteries. At 25 bucks a piece, I want to get as much life out of them as possible.

As it was, I was quite surprised at how long they did NOT last, I only got a few minutes of full power for each battery (I have two, I changed them out using one at a time) before they were too low to be used correctly.

I am flying an Easy Glider electric sailplane and from what I was told, I should be able to get 10 minutes or so at full throttle on the stock issue, geared Permax 400 motor and the 2 cel 2000 maH Li-Po that I have. This is a brushed motor with a gearbox which I would assume would be fairly inefficient, so I am planning on putting an outrunner on it until I get better at thermaling.

Matthew Allen

Generally people say 3v per cell should be the safety cut-off, but bear in mind that this is UNDER LOAD. If it's reading 5.7v at rest it may have pulled it a lot lower when it was running. The battery may recover though the chances are you've done some damage.

With lipos, you must be very careful with a cell that may have suffered damage. I'm not saying don't use it, but be very careful charging it (do it in some kind of fire-limiting set-up, I use Pyrex dishes) and inspect it closely the next few times you use it. If it shows any signs at all of swelling, discard it by a safe method. The best method is rather a hotly debated subject, but if you do a search here or on RCGroups.com I'm sure you'll get lots of information.

Regarding your setup, do you know the current draw, or have you calculated what it should be? Does it fall below the max continuous draw of your packs? The problem with lipos, especially the less expensive ones, is that the ratings are often 'optimistic' in the extreme. I've had packs labeled 10C that flagged seriously after 30 flights at well under that. It's a consequence of the huge competition in the lipo market - people inflate the specs of their products.

Matthew

JoshGordon

What kind of charger are you using?
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Joshua Gordon
Common Sense RC
www.CommonSenseRC.com
Toll Free 866-405-8811

Maine_Flyer

someting dosen't sound right.. the geared S400 can't be drawing much more then 10amps and the pack should have been more then adequite... sounds like the packs weren't charged to me and the ESC recognized it as a nimh pack or something...