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Old Jul 12, 2004, 01:11 PM
Wan
Guest
n/a Posts
Oh, oh. Li Poly overcharged?

I was charging my 3S 1500 mAh, 11.1 V Kokam battery and had to leave.
When I returned to resume charging it ended with a 13.3V when it
should have been 12.60 V or so. It also checked out the same with a
volt meter. I should mention that it was unintentionally charged at
14.30 volts.

The battery is bloated in appearance but not hot to the touch. I put
the battery into a thick glass baking covered dish.

I wonder if the battery can be trusted for use or is it just toast?

Wan
Old Jul 12, 2004, 03:11 PM
Martin X. Moleski, SJ
Guest
n/a Posts
Re: Oh, oh. Li Poly overcharged?

On 12 Jul 2004 09:37:42 -0700, wanjung@toast.net (Wan) wrote:

>I was charging my 3S 1500 mAh, 11.1 V Kokam battery and had to leave.
>When I returned to resume charging it ended with a 13.3V when it
>should have been 12.60 V or so. It also checked out the same with a
>volt meter. I should mention that it was unintentionally charged at
>14.30 volts.


>The battery is bloated in appearance but not hot to the touch. I put
>the battery into a thick glass baking covered dish.


>I wonder if the battery can be trusted for use or is it just toast?


Seems to me you've just become a "test pilot" for the
group.

If it doesn't blow up in the next few hours, and if it stays
charged, go fly it and see what happens.

The next time you charge it, it might be wise to do it
outdoors and outside of the aircraft.

Then let us know how it all turned out. )

I wouldn't charge it indoors ever again, even if it passes
its test flight and recharge. YMMV.

DIsclaimer: I have never used any LiPo batteries. I'm just
an interested bystander well outside of the range of exploding
battery packs.

Marty
Old Jul 12, 2004, 03:11 PM
Red Scholefield
Guest
n/a Posts
Re: Oh, oh. Li Poly overcharged?

Bloated = bad, as in toast! You are fortunate it wasn't scrambled eggs.
--
Red S.
Red's R/C Battery Clinic
http://www.rcbatteryclinic.com
Check us out for "revolting" information.

"Wan" <wanjung@toast.net> wrote in message
news:7387603e.0407120837.7f2d6df@posting.google.co m...
> The battery is bloated in appearance but not hot to the touch.
> I wonder if the battery can be trusted for use or is it just toast?
>
> Wan







Old Jul 12, 2004, 03:11 PM
Abel Pranger
Guest
n/a Posts
Re: Oh, oh. Li Poly overcharged?

On 12 Jul 2004 09:37:42 -0700, wanjung@toast.net (Wan) wrote:

>I was charging my 3S 1500 mAh, 11.1 V Kokam battery and had to leave.
>When I returned to resume charging it ended with a 13.3V when it
>should have been 12.60 V or so. It also checked out the same with a
>volt meter. I should mention that it was unintentionally charged at
>14.30 volts.
>
>The battery is bloated in appearance but not hot to the touch. I put
>the battery into a thick glass baking covered dish.
>
>I wonder if the battery can be trusted for use or is it just toast?
>
>Wan


Hi Wan-
My newsreader shows two responses so far, from Red and Marty, both
pretty sharp guys but here with opposing views. FWIW, here's my shot
at a tiebreaker vote: Apply a load (like a 10 ohm resistor) to
completely discharge it, puncture the poly envelopes of the bloated
cells while tryng to avoid contact between the knife and the envelope
contents, soak them in water that you have added some table salt to
for a few hours to neutralize them, then throw 'em in the trash can
(they are not considered hazardous waste like NiCd's). They're
expensive I know, but the risk of fire from a damaged or even slightly
suspicious pack is just too real to overlook. Every incident adds to
the type of bad press that could get them banned by for our use by AMA
or by real authorities.

Abel
Old Jul 12, 2004, 05:11 PM
Martin X. Moleski, SJ
Guest
n/a Posts
Re: Oh, oh. Li Poly overcharged?

On Mon, 12 Jul 2004 18:10:16 GMT, abel_pranger@yahoo.com (Abel
Pranger) wrote:

>On 12 Jul 2004 09:37:42 -0700, wanjung@toast.net (Wan) wrote:
>
>>I was charging my 3S 1500 mAh, 11.1 V Kokam battery and had to leave.
>>When I returned to resume charging it ended with a 13.3V when it
>>should have been 12.60 V or so. It also checked out the same with a
>>volt meter. I should mention that it was unintentionally charged at
>>14.30 volts.
>>
>>The battery is bloated in appearance but not hot to the touch. I put
>>the battery into a thick glass baking covered dish.
>>
>>I wonder if the battery can be trusted for use or is it just toast?
>>
>>Wan

>
>Hi Wan-
>My newsreader shows two responses so far, from Red and Marty, both
>pretty sharp guys but here with opposing views.


I defer to Red's advice. He's an expert. I'm not.

> ... They're
>expensive I know, but the risk of fire from a damaged or even slightly
>suspicious pack is just too real to overlook.


Agreed 110%.

I proposed an experiment that might let Wan get some flights
from the pack. But LiPo's have a reputation for starting
fires--especially after they puff up. (

Marty
Old Jul 12, 2004, 09:11 PM
Roger
Guest
n/a Posts
Re: Oh, oh. Li Poly overcharged?

Mine didn't even puff up or get hot. They just spontaneously combusted
after 2 hours and 15 munutes of sitting, unconnected to anything, in an
airconditioned room. Nobody seems to know why, either.
Until they get some kind of track record on these things, I am done with
electrics. I followed the instructions, used the right charger, at the
right voltage and current, and ended up losing a $24 battery pack, $40
reciever, and 2 micro servos. All that survived was the ESC, because it
wasn't in the airplane at the time.
Expensive lesson.

Martin X. Moleski, SJ wrote:
> On Mon, 12 Jul 2004 18:10:16 GMT, abel_pranger@yahoo.com (Abel
> Pranger) wrote:
>
>
>>On 12 Jul 2004 09:37:42 -0700, wanjung@toast.net (Wan) wrote:
>>
>>
>>>I was charging my 3S 1500 mAh, 11.1 V Kokam battery and had to leave.
>>>When I returned to resume charging it ended with a 13.3V when it
>>>should have been 12.60 V or so. It also checked out the same with a
>>>volt meter. I should mention that it was unintentionally charged at
>>>14.30 volts.
>>>
>>>The battery is bloated in appearance but not hot to the touch. I put
>>>the battery into a thick glass baking covered dish.
>>>
>>>I wonder if the battery can be trusted for use or is it just toast?
>>>
>>>Wan

>>
>>Hi Wan-
>>My newsreader shows two responses so far, from Red and Marty, both
>>pretty sharp guys but here with opposing views.

>
>
> I defer to Red's advice. He's an expert. I'm not.
>
>
>>... They're
>>expensive I know, but the risk of fire from a damaged or even slightly
>>suspicious pack is just too real to overlook.

>
>
> Agreed 110%.
>
> I proposed an experiment that might let Wan get some flights
> from the pack. But LiPo's have a reputation for starting
> fires--especially after they puff up. (
>
> Marty


Old Jul 12, 2004, 09:11 PM
The Natural Philosopher
Guest
n/a Posts
Re: Oh, oh. Li Poly overcharged?

Wan wrote:

> I was charging my 3S 1500 mAh, 11.1 V Kokam battery and had to leave.
> When I returned to resume charging it ended with a 13.3V when it
> should have been 12.60 V or so. It also checked out the same with a
> volt meter. I should mention that it was unintentionally charged at
> 14.30 volts.
>
> The battery is bloated in appearance but not hot to the touch. I put
> the battery into a thick glass baking covered dish.
>
> I wonder if the battery can be trusted for use or is it just toast?
>


Its more sausage than toast.

Either way is probably shagged.

> Wan


Old Jul 12, 2004, 09:11 PM
Wan
Guest
n/a Posts
Re: Oh, oh. Li Poly overcharged?

abel_pranger@yahoo.com (Abel Pranger) wrote in message news:<40f2d026.9051685@news.toast.net>...
> On 12 Jul 2004 09:37:42 -0700, wanjung@toast.net (Wan) wrote:
>
> >I was charging my 3S 1500 mAh, 11.1 V Kokam battery and had to leave.
> >When I returned to resume charging it ended with a 13.3V when it
> >should have been 12.60 V or so. It also checked out the same with a
> >volt meter. I should mention that it was unintentionally charged at
> >14.30 volts.
> >
> >The battery is bloated in appearance but not hot to the touch. I put
> >the battery into a thick glass baking covered dish.
> >
> >I wonder if the battery can be trusted for use or is it just toast?
> >
> >Wan

>
> Hi Wan-
> My newsreader shows two responses so far, from Red and Marty, both
> pretty sharp guys but here with opposing views. FWIW, here's my shot
> at a tiebreaker vote: Apply a load (like a 10 ohm resistor) to
> completely discharge it, puncture the poly envelopes of the bloated
> cells while tryng to avoid contact between the knife and the envelope
> contents, soak them in water that you have added some table salt to
> for a few hours to neutralize them, then throw 'em in the trash can
> (they are not considered hazardous waste like NiCd's). They're
> expensive I know, but the risk of fire from a damaged or even slightly
> suspicious pack is just too real to overlook. Every incident adds to
> the type of bad press that could get them banned by for our use by AMA
> or by real authorities.
>
> Abel


Abel,

We certainly don't want any authorities banning the Li Po batteries. I
have heard from this group that Li Polies are banned from a club
field. A bit of paranoia! Matter of fact, I sold my NiMH batteries to
a member of that club where Li Po batteries are banned.

The LHS where I purchased a replacement tried to call a "Battery
Place" to see if they would dispose of my battery, but no one
answers the phone.

Now it's sitting outside on a concrete slab, as I've told Red in a
private message. I thought about burying it in the dirt. Is this a
good idea?

Wan
Old Jul 12, 2004, 11:11 PM
Abel Pranger
Guest
n/a Posts
Re: Oh, oh. Li Poly overcharged?

On 12 Jul 2004 18:01:41 -0700, wanjung@toast.net (Wan) wrote:


>Abel,
>
>We certainly don't want any authorities banning the Li Po batteries. I
>have heard from this group that Li Polies are banned from a club
>field. A bit of paranoia! Matter of fact, I sold my NiMH batteries to
>a member of that club where Li Po batteries are banned.
>
>The LHS where I purchased a replacement tried to call a "Battery
>Place" to see if they would dispose of my battery, but no one
>answers the phone.
>
>Now it's sitting outside on a concrete slab, as I've told Red in a
>private message. I thought about burying it in the dirt. Is this a
>good idea?
>
>Wan


Hi Wan-
"That" club is one I belong to, and I bought your NiMH packs.
The safe method of disposal I outlined came from an article on the FMA
Direct web page, if I have recalled the pertinant points correctly.
If Fred Marks doesn't know the right way to dispose of damaged LiPo
cells, then I guess we're all in deep yogurt!
Chemistry at the undergrad level is something in the distant past for
me, but Fred's advice seemed sound. Your precautions re keeping the
suspect pact in covered ovenware or on a slab of concrete seem like
sound and sufficient precautions to me. Why not just give them a
stab while they are immersed in saline solution in your ovenware?
When they fail catastrophically, they don't explode, they just emit
hot gasses that could ignite something. . Absent anything that will
burn in close proximity, and not many things burn under water, I don't
think there is any significant safety risk to you in prepping them for
disposal that way. Probably a lot more responsible than just tossing
them in a dumpster somewhere too, as I expect is the usual way people
get rid of dead LiPo's from their laptops and cell phones.

Abel

Old Jul 13, 2004, 07:11 AM
MLB
Guest
n/a Posts
Re: Oh, oh. Li Poly overcharged?

Hi! Fry!

Here is a nice link. You can see some interesting pictures of LiPo
overcharged or mischarged. This is a french site but the info is still
valuable.

http://klaudius.free.fr/lipo.htm

Have a nice fry party (sorry, Fly party?)

MLB
marc.lebret@wanadoo.fr

On 2004-07-13 02:42:40 +0200, The Natural Philosopher <a@b.c> said:

> Wan wrote:
>
>> I was charging my 3S 1500 mAh, 11.1 V Kokam battery and had to leave.
>> When I returned to resume charging it ended with a 13.3V when it
>> should have been 12.60 V or so. It also checked out the same with a
>> volt meter. I should mention that it was unintentionally charged at
>> 14.30 volts.
>>
>> The battery is bloated in appearance but not hot to the touch. I put
>> the battery into a thick glass baking covered dish.
>>
>> I wonder if the battery can be trusted for use or is it just toast?
>>

>
> Its more sausage than toast.
>
> Either way is probably shagged.
>
>> Wan



Old Jul 13, 2004, 09:11 AM
Wan
Guest
n/a Posts
Re: Oh, oh. Li Poly overcharged?

abel_pranger@yahoo.com (Abel Pranger) wrote in message news:<40f3470e.39496615@news.toast.net>...
> On 12 Jul 2004 18:01:41 -0700, wanjung@toast.net (Wan) wrote:
>
>
> >Abel,
> >
> >We certainly don't want any authorities banning the Li Po batteries. I
> >have heard from this group that Li Polies are banned from a club
> >field. A bit of paranoia! Matter of fact, I sold my NiMH batteries to
> >a member of that club where Li Po batteries are banned.
> >
> >The LHS where I purchased a replacement tried to call a "Battery
> >Place" to see if they would dispose of my battery, but no one
> >answers the phone.
> >
> >Now it's sitting outside on a concrete slab, as I've told Red in a
> >private message. I thought about burying it in the dirt. Is this a
> >good idea?
> >
> >Wan

>
> Hi Wan-
> "That" club is one I belong to, and I bought your NiMH packs.
> The safe method of disposal I outlined came from an article on the FMA
> Direct web page, if I have recalled the pertinant points correctly.
> If Fred Marks doesn't know the right way to dispose of damaged LiPo
> cells, then I guess we're all in deep yogurt!
> Chemistry at the undergrad level is something in the distant past for
> me, but Fred's advice seemed sound. Your precautions re keeping the
> suspect pact in covered ovenware or on a slab of concrete seem like
> sound and sufficient precautions to me. Why not just give them a
> stab while they are immersed in saline solution in your ovenware?
> When they fail catastrophically, they don't explode, they just emit
> hot gasses that could ignite something. . Absent anything that will
> burn in close proximity, and not many things burn under water, I don't
> think there is any significant safety risk to you in prepping them for
> disposal that way. Probably a lot more responsible than just tossing
> them in a dumpster somewhere too, as I expect is the usual way people
> get rid of dead LiPo's from their laptops and cell phones.
>
> Abel


Hi Abel, Now I remember you. I just discarded your envelope for the
check you sent for the NiMH batteries.

The battery is still out there and I will do as you suggested. It's
the prudent thing.

Thanks,
Wan
Old Jul 13, 2004, 09:11 AM
Wan
Guest
n/a Posts
Re: Oh, oh. Li Poly overcharged?

The Natural Philosopher <a@b.c> wrote in message news:<ccvb9c$3pm$4$8302bc10@news.demon.co.uk>...
> Wan wrote:
>
> > I was charging my 3S 1500 mAh, 11.1 V Kokam battery and had to leave.
> > When I returned to resume charging it ended with a 13.3V when it
> > should have been 12.60 V or so. It also checked out the same with a
> > volt meter. I should mention that it was unintentionally charged at
> > 14.30 volts.
> >
> > The battery is bloated in appearance but not hot to the touch. I put
> > the battery into a thick glass baking covered dish.
> >
> > I wonder if the battery can be trusted for use or is it just toast?
> >

>
> Its more sausage than toast.
>
> Either way is probably shagged.


TNP, You have a very good sense of humor. I was so glad to hear from
Abel who bought my NiMH batteries that I hadn't read yours.

Thanks for making any problem entertaining! BTW I liked sausage more
than toast.

Wan
Old Jul 13, 2004, 09:11 AM
MJC
Guest
n/a Posts
Re: Oh, oh. Li Poly overcharged?

I think it's a good bet that any battery that ACTUALLY CHANGES SHAPE after a
charge has been turned into explosive hazardous waste.

MJC

"Wan" <wanjung@toast.net> wrote in message
news:7387603e.0407120837.7f2d6df@posting.google.co m...
> I was charging my 3S 1500 mAh, 11.1 V Kokam battery and had to leave.
> When I returned to resume charging it ended with a 13.3V when it
> should have been 12.60 V or so. It also checked out the same with a
> volt meter. I should mention that it was unintentionally charged at
> 14.30 volts.
>
> The battery is bloated in appearance but not hot to the touch. I put
> the battery into a thick glass baking covered dish.
>
> I wonder if the battery can be trusted for use or is it just toast?
>
> Wan



Old Jul 13, 2004, 05:11 PM
Wan
Guest
n/a Posts
Re: Oh, oh. Li Poly overcharged?

MLB <marc.lebret@wanadoo.fr> wrote in message news:<2004071311211916807%marclebret@wanadoofr>...
> Hi! Fry!
>
> Here is a nice link. You can see some interesting pictures of LiPo
> overcharged or mischarged. This is a french site but the info is still
> valuable.
>
> http://klaudius.free.fr/lipo.htm
>
> Have a nice fry party (sorry, Fly party?)
>
> MLB
> marc.lebret@wanadoo.fr


MLB, The photos appear frightening. Were the first three set up on a
foam box for some kind of test? They seemed to be expecting the flare
up with those sequential pictures.

The person with the crash photos must have mega bucks invested in
batteries.

Thanks for passing it along, Hope it doesn't discourage anyone from Li
Poly batteries.

Wan

>
> On 2004-07-13 02:42:40 +0200, The Natural Philosopher <a@b.c> said:


> >
> >> I was charging my 3S 1500 mAh, 11.1 V Kokam battery and had to leave.
> >> When I returned to resume charging it ended with a 13.3V when it
> >> should have been 12.60 V or so. It also checked out the same with a
> >> volt meter. I should mention that it was unintentionally charged at
> >> 14.30 volts.
> >>
> >> The battery is bloated in appearance but not hot to the touch. I put
> >> the battery into a thick glass baking covered dish.
> >>
> >> I wonder if the battery can be trusted for use or is it just toast?
> >>

> >
> > Its more sausage than toast.
> >
> > Either way is probably shagged.
> >
> >> Wan

Old Jul 13, 2004, 09:11 PM
John Privett
Guest
n/a Posts
Re: Oh, oh. Li Poly overcharged?

Wan wrote:
>
> MLB, The photos appear frightening. Were the first three set up on a
> foam box for some kind of test? They seemed to be expecting the flare
> up with those sequential pictures.


The text before this explains that a significant over-charge risks
destruction of the battery. It then states that the pictures show what
happens when a cell is significantly overcharged. I guess it was setup
deliberately.

I'm sure the rest were *not* deliberate though!
--
John P. - who flies on Epsom Downs, UK.
http://www.flyrc.org.uk/
I'm sick of spam, so replace 'nojunkthanks' with 'john' if you want me
to read any e-mailed reply!


 


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