Wattflyer RC Network: RC Universe :: RCU Magazine :: RCU Forums :: RCU Classifieds :: RCU User Reviews :: RCU YouTube
Home Who's Online Calendar Today's Posts RealTime Post Spy Mark Forums Read
Go Back   WattFlyer RC Electric Flight Forums - Discuss radio control eflight > R/C Electric Power - Batteries, Chargers, ESCs and More > Batteries & Chargers
Register Members List Wattflyer Extras Articles Search Today's Posts Mark Forums Read Social Groups

Batteries & Chargers Discuss Li-P, Li-Ion, NiMh, Nicad battery technology and the chargers that juice 'em up!

Thank you for your support (hide ads)
Reply
 
Thread Tools Display Modes
Old 12-02-2013, 03:27 AM   #1
tobydogs
love to build!
 
tobydogs's Avatar
 
Join Date: Jan 2010
Location: nj usa
Posts: 2,844
Thanked 197 Times in 194 Posts
Club: rcrcc rockland county,ny
Awards Showcase

Outstanding Contributor Award 
iTrader: (0)
Friends: (13)
Default snap,crackle and smoke....another battery gone.

once again the 4 prong garden rake poked another damaged lipo. PUFF!!

i'll never understand how folks can stand having puffed lipos in there storage or flight box. last night i found one of my 4cell 4000mah 40c lipos slightly puffed. all these are new batteries but this one went down hard in the 540t edge and got damaged.i taped it after peeling the shrink wrap back to examine the damage and thought it was ok. last night i had it parallel charging with three other same size packs but the charger was in safety mode. so i checked them all and this bad pack had a damaged #2cell.

i thought i would bring all the cells down and charge it slowly,ran it on a bench motor and found #2 cell dead...........what to do

i know! pop this baby at night! she was warm from having run on the bench and even more puffed. i took a four prong rake with sharp points and whacked it hard........thats the part where pressure released with a sharp snap!! then instant smoke and a crackling hissing sound along with a orange glow that traveled the length of the pack.i could tell there wasn't any wind as the cloud of smoke just hung around.

man,I'm glad it's gone the way of many old packs and isn't sitting in my storage cabinet with my other lipo's. if lipos puff,it means the foil type wrap of the cells are expanded and a possible seam break could follow at any time...how do folks sleep at night if their puffed lipos aren't stored in a fire/smoke proof area.

narrow is the place to land...wide is the space to crash....choose the narrow way!
tobydogs is offline  
  Reply With Quote
Old 12-02-2013, 05:54 AM   #2
JetPlaneFlyer
Super Contributor
 
Join Date: Mar 2009
Location: Aberdeen, Scotland
Posts: 3,980
Thanked 455 Times in 423 Posts
Awards Showcase

5kW  Outstanding Contributor Award  1kW 
iTrader: (0)
Friends: (7)
Default

I'm with you, any significant puffing means it goes in the trash. Thing is that puffing doesn't happen by itself, it indicates that the battery is seriously compromised and usually it's not usable (in my applications) by that point anyway.
JetPlaneFlyer is offline  
  Reply With Quote
Old 12-02-2013, 06:15 PM   #3
Larry3215
Look out for that tree!!!
 
Larry3215's Avatar
 
Join Date: Mar 2006
Location: Gig Harbor, Wa USA
Posts: 6,714
View Larry3215's Gallery63
Thanked 688 Times in 667 Posts
Club: Kitsap ARCS & E-FLAPS
Awards Showcase

90 Minute Thermal Duration  60 Minute Thermal Duration  30 Minute Thermal Duration  4kW 
iTrader: (6)
Friends: (21)
Default

+372

I think I need a signature.
Larry
Larry3215 is offline  
  Reply With Quote
Old 12-02-2013, 06:41 PM   #4
dahawk
Super Contributor
 
dahawk's Avatar
 
Join Date: Jul 2011
Location: Keller, TX
Posts: 3,141
View dahawk's Gallery6
Thanked 189 Times in 185 Posts
Club: 114th RC Aero Squadron
iTrader: (0)
Friends: (19)
Default

I have a few very slightly puffed lipos. All cells still showing proper voltage and balance. Not enough to get my bowels in an uproar. When they get to far out of whack, they're useless to me anyway. Keep them stored in an ammo container.

I have experienced a lipo fire at the field and witnessed a few others. I had a situation when the shock load from landing one of little skyangels forced the lipo into the motor shaft penetrating the packaging. Not a pretty site. A lot of pressure builds up in these batteries.

Wounded Warrior Fun Fly - Aug 16th ,2014 - Grapevine TX - Info link: https://support.woundedwarriorprojec...ising/RCPilots
dahawk is offline  
  Reply With Quote
Old 12-02-2013, 06:46 PM   #5
JetPlaneFlyer
Super Contributor
 
Join Date: Mar 2009
Location: Aberdeen, Scotland
Posts: 3,980
Thanked 455 Times in 423 Posts
Awards Showcase

5kW  Outstanding Contributor Award  1kW 
iTrader: (0)
Friends: (7)
Default

It's not the ability to charge and balance to full voltage that usually spells the end for a LiPo. Usually its increasing internal resistance that does it. It quickly gets to the point where voltage is sagging so much as to hit LVC prematurely. By the time I notice any swelling I've usually already noticed performance dropping away.

I've yet to find a LiPo that showed any significant swelling and still performed ok in terms of voltage sag.
JetPlaneFlyer is offline  
  Reply With Quote
Reply

  WattFlyer RC Electric Flight Forums - Discuss radio control eflight > R/C Electric Power - Batteries, Chargers, ESCs and More > Batteries & Chargers

« Previous Thread | Next Thread »

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Another posting on "C" and what it indicates kyleservicetech Batteries & Chargers 5 03-11-2012 07:51 AM
Noob Cant figure out how to match batteries to motors please help Otonzer Scratch and Kit Built Aircraft 7 02-26-2012 12:01 AM
Always wanted a smoke trail from my plane.... Captainchris General Electric Discussions 11 11-16-2011 05:23 PM
How to use a RC Lipo charger properly? SimonXi Power Systems 0 08-17-2011 11:02 AM
Solid experience on RC Model Lipo Battery Accident & Charger Guide SimonXi Batteries & Chargers 0 08-12-2011 05:08 PM


All times are GMT +1. The time now is 02:06 AM.


Powered by: vBulletin
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright 2005 WattfFlyer.com
RCU Eflight HQ

Charities we support Select: Yorkie Rescue  ::  Crohn's & Colitis Foundation



Page generated in 0.18497 seconds with 29 queries