Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Batteries & Chargers => Topic started by: essex2visuvesi on July 31, 2010, 01:45:20 pm

Title: Li Po wont charge
Post by: essex2visuvesi on July 31, 2010, 01:45:20 pm
One of my Li Po Packs has quit working on me :(

I charged it up the other day and it was working fine.  Was going to use it but on arriving at the lake there was too much current so it was left in the car.
I forgot to disconnect the battery from the Lipo Warning alarm and it has slowly discharged itself untill the low vooltage buzzer woke me up yesterday morning.  It was duly disconnected.
when I tried to charge it today it wont charge.  There is no problem with the charger as I used it to charge a different li po pack and it charged fine

Any Ideas?
Title: Re: Li Po wont charge
Post by: Subculture on July 31, 2010, 01:53:55 pm
You may well ahve discharged it beyond 3.0 volt per cell which will kill the pack. You have to take care with lipos in this respect I'm afraid.
Title: Re: Li Po wont charge
Post by: poddy on July 31, 2010, 02:10:19 pm
Some info  on the subject here >>>>

http://www.rcgroups.com/forums/showthread.php?t=783780
Title: Re: Li Po wont charge
Post by: dodgy geezer on July 31, 2010, 02:20:32 pm
Here is Giant Cod on LiPo resuscitation...

http://www.giantcod.co.uk/forum/viewtopic.php?f=15&t=3355

They give a point-by-point how-to-do-it guide, and cover the safety aspects.....
Title: Re: Li Po wont charge
Post by: essex2visuvesi on July 31, 2010, 05:54:49 pm
A replacement pack is ony 15 quid, for the danger involved with my fists of ham and buttered fingers a new pack is a far better option
Title: Re: Li Po wont charge
Post by: dodgy geezer on July 31, 2010, 06:37:32 pm
From what I can see from the Giant Cod site it just means that the battery has become unbalanced - it should be fine if the low cell is brought up to the same charge as the rest... 
Title: Re: Li Po wont charge
Post by: snowwolflair on July 31, 2010, 08:29:16 pm
There are old LiPo users and there are bold LiPo users but no old bold LiPo users :-)
Title: Re: Li Po wont charge
Post by: dodgy geezer on July 31, 2010, 08:34:25 pm
and then there's me....
Title: Re: Li Po wont charge
Post by: The long Build on July 31, 2010, 08:55:35 pm
and then there's me....

And hopefully only 1 as well, not sure this forum Could take 2 of you.. :} {-) %%
Title: Re: Li Po wont charge
Post by: dodgy geezer on July 31, 2010, 09:50:58 pm
And hopefully only 1 as well, not sure this forum Could take 2 of you.. :} {-) %%

That's funny, you know... everyone I've ever met has said the same thing about me...... {:-{ {:-{
Title: Re: Li Po wont charge
Post by: essex2visuvesi on August 01, 2010, 08:25:34 am
That's funny, you know... everyone I've ever met has said the same thing about me...... {:-{ {:-{

I am not a complete idiot. Parts of me are missing....


Thats what worries me.... where are these parts?
Title: Re: Li Po wont charge
Post by: RaaArtyGunner on August 01, 2010, 08:32:21 am

In the parts box where else  O0 {-)
Title: Re: Li Po wont charge
Post by: dodgy geezer on August 01, 2010, 08:57:14 am
Actually, so much has fallen off that there must be enough in the box to build a mini-me....

By the way, have you seen my new Taycol motor web-site? I have just put it up, and quite like the KK handbook page turning. It might be fun to run a Taycol on LiPos - I wonder how fast they would go....
Title: Re: Li Po wont charge
Post by: essex2visuvesi on August 01, 2010, 01:20:14 pm
Well I did a voltage check just to be sure

0.2V on cell 1
0.25V on cell 2
3.2V on cell 3

Title: Re: Li Po wont charge
Post by: Subculture on August 02, 2010, 08:05:49 am
Get a new pack.
Title: Re: Li Po wont charge
Post by: andrewh on August 03, 2010, 01:04:26 pm
If a lipo is discharged below its "chemistry limit"  - between 2.4 and 3V/cell it MAY never be able to operate again

BUT, many people have recovered flat cell by trickle charging at VERY low currents for a long time and seemingly the cell creeps up to 3V or so, and can then be carefully charged (but I would do it gently until I was sure that I had a lipo, and not a puff, puff BANG)
andrew
Title: Re: Li Po wont charge
Post by: tomo55 on September 15, 2010, 07:17:23 pm
Its a dead Lipo dispose of safely and buy another.
chris
Title: Re: Li Po wont charge
Post by: essex2visuvesi on September 15, 2010, 09:36:59 pm
I didnt want to mess with the charging thing so bought a new pack.

Trying to find out how to dispose of the old one now
Title: Re: Li Po wont charge
Post by: Subculture on September 15, 2010, 10:19:50 pm
Put it in a plastic bag and put it out for recycling, that's what i do with any dead battery.
Title: Re: Li Po wont charge
Post by: nick_75au on September 19, 2010, 09:22:12 am
Just put a low watt bulb on it to completely discharge it, then can be thrown out with household  rubbish. Best not to leave voltage in the pack, the garbage man might get a nasty surprise on the way back to the tip

nick
Title: Re: Li Po wont charge
Post by: tomo55 on September 19, 2010, 12:43:38 pm
most recycling centres have a household battery disposal point.
chris
Title: Re: Li Po wont charge
Post by: dougal99 on September 21, 2010, 05:30:31 pm
Just put a low watt bulb on it to completely discharge it, then can be thrown out with household  rubbish. Best not to leave voltage in the pack, the garbage man might get a nasty surprise on the way back to the tip

nick

Don't know the rules in Oz or Finland, but in UK and many countries in Europe batteries should never be disposed of in household rubbish (of any sort, we currently have 3 different bins  %% ) but taken to the recycling centre and placed in the approriate area. The law is changing abd failure to dispose correctly can result in a significant monetary penalty.
Title: Re: Li Po wont charge
Post by: Tombsy on September 21, 2010, 09:31:28 pm
Lipo batteries do not have toxic heavy metals and are safe for landfills.
Title: Re: Li Po wont charge
Post by: dodgy geezer on September 22, 2010, 09:08:20 am
Lipo batteries do not have toxic heavy metals and are safe for landfills.

Now all you have to do is explain that to an official who is drunk with power and has the ability to have you arrested or fined under a wide variety of terrorist-inspired catch-all laws....
Title: Re: Li Po wont charge
Post by: Netleyned on September 22, 2010, 10:26:35 am
Every shop that sells batteries should have a recycling bin now.
Most of the ones I've seen are just like a big single cell.
A LiPo is probably the least toxic of anything thrown in these.

Ned
Title: Re: Li Po wont charge
Post by: snowwolflair on September 22, 2010, 10:41:05 am
Now all you have to do is explain that to an official who is drunk with power and has the ability to have you arrested or fined under a wide variety of terrorist-inspired catch-all laws....

Local authority dumps have a statutory duty to accept them, but they may charge.