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modelman
12-28-2011, 01:01 PM
I guess I have already killed a brand new 7.2V lipo pack. I turned everything off and left it plugged in and it somehow drained the pack to 1.8V. Now it won't take a charge. Is there any way to bring the pack back to life or is it ruined?

Lil Giants
12-28-2011, 02:01 PM
You have two esc's in your 777? One for for/rev & the other dump? Turn off switches on both esc's?

I have a master switch on my JD850, the only model I use lipos on, never a problem leaving the batt plugged in, yesterday being the 1st time in two wks that I used it.

I believe your lipo is toast Tom, anything below 2.7v per cell & they're ruined! Do you have voltage cut-off on one of your esc's?

fhhhstix
12-28-2011, 02:41 PM
Do not leave it plugged in unless you have a master switch separate from the esc's switch and then I still would not leave it plugged in. Some esc's do not truly shut off with the switch they just prevent the esc from having out put but some of the circuitry stays powered up. Castle creations which has some great esc's don't get me wrong but they can be a parasite on a battery with the switch off. Why do I know this I have killed a Li Po my self.

Travis

modelman
12-28-2011, 03:06 PM
Joe-I do not have-2-esc's. A relay controls the dump box and I do have the lipo cutoff enabled on the esc. fishhhstix-thanks for the info-I guess lesson learned on lipos.

hippy
12-28-2011, 08:45 PM
do you have a regular charger? if so, put it on its lowest setting, plug battery in and do a slow charge. watch it! give it a min and try to put back on lipo charger. might take a couple min to do. this is not recommended to do. but be very careful and watch the battery. it should come back.

derailed
12-28-2011, 09:20 PM
i almost lost a lipo
connected to a normal charger for seconds
the charge it pushed was enough to breathe life back into the lipo
as good as new again
careful tho
you can burn your house down this way

9W Monighan
12-28-2011, 10:56 PM
I'm trying a All Battery Li-Ion pack that has a built in circuit board to regulate the charge and cut out the discharge. Time will tell if it is a good pack. I sent the charger I bought with it back because it was DOA. Had a heck of a time getting the customer service to understand English!!

pigeonfarmboy
12-29-2011, 12:15 PM
Yeah don't try to bring it back. It's just that little E-flite pack yeah? Not even worth having to smell a smoking lipo let alone if it flares up. Take it and get it recycled. I never leave packs plugged in and definitely not on an expensive model.

modelman
12-29-2011, 06:08 PM
Yes it is the E-flite lipo pack I am using. It is the only one I could find that will fit in my truck. I am ordering a new pack but after reading the posts from hippy and derailed I decided to try to bring the pack "back to life". I was successful and it is once again running in the truck. I will explain how I did it if anyone is interested.

trucker n
12-29-2011, 06:55 PM
i just tried this trick on 2 of my lipos and worked great i wish inew about this along time ago:D

fhhhstix
12-29-2011, 07:05 PM
Just so you guys know yes this does work but this is the same as lighting a firework and hoping it doesn't go off.:eek: Just because you got by with it this time doesn't mean it will work every time.:rolleyes: The price of a new Li Po and a lesson learned is a lot cheaper than burning down your house or garage.:cool:

Travis

modelman
12-29-2011, 09:29 PM
I'm sure this is not a recommended or safe practice but you must use common sense. I charged at only 75mah and monitored the pack with a volt meter and it never even got warm to the touch so I knew it was okay.

hippy
12-30-2011, 11:30 AM
i just tried this trick on 2 of my lipos and worked great i wish inew about this along time ago:D


you should have asked earlier, just kidding, ya we been using that trick for a few years now. just be very careful doing it! oh i hope you did this outside, cause your house aint worth it. but then again we have blown a few up due to being over shaken in our race trucks. shakes a connection inside loose and footballed it became! for it to blow up though, it took us 2 copper pellet shots to brake the housing and then fireworks started. it is more of the fumes to worry about. those fumes are really toxic! besafe, enjoy, and remember shinny side up! unless your a rock crawler!

Bill 832
12-30-2011, 04:07 PM
I race RC short course trucks twice a week and we have been using lipos now for a couple of years. Sorry bud, but your pack is toast. I have seen a pack or two go up, and it's not worth the risk. If you unplug your packs, it will hold a charge all winter long, but plugged in, it will be dead in a week or less. Lipo packs are nothing to toy with, i can tell you that much for sure!