As Kimbalion has said DO NOT artificially cool the batteries at any stage prior or during charging. It is not even recommended to cool the batteries with fans while charging. You are artificially changing the charging process which involves a chemical reaction

Thanks for clearing that up guy's,. much appreciated

Well it all sounds like pretty good advice to me so far.
However in this case
1. What I observed was the room enclosed was pretty dam hot to start with.
2. A batt sonny was charging was at excessivly hot after 20 min of charging that was on when I saw him.
3. These batts were used in 540 hence they may have been bent from a hit causing a bar to neg hard short. Diffical to tell cause not much left of them.
4. The lower the mV used in charging the higher the volts any way "read the manual”. It says mV drop off so I would go for the lowest that doesn’t false peak and try to get 45 deg 125f so the electrite is fully active and that is it.
5. I have only seen this when some real nice DOGY guy shotted out my pack cause they were spread out in the boot of my car cooling down at Wynnum last year
6. WC do defiantly get hotter so a lower mV is defiantly the go there.
7. Use a volt meter to check the cut off is working proper.
8. Never trust the temp by its self us a temp gun to confirm on all cells when charging not just the one the sender is connected too.
9. Just go to member all that and you wont have a problem.
10. Oh year if you see it get to 60 deg surface temp just remember that’s gana cost you more money causse your killing them no doubt.

Hop this helps

Seems my ignorance has been around since i started rc over 2 years ago.

Never even new what peak mv setting meant or have i ever heard anyone talk about it. Checked my ice charger and it reads:

Peak sens' 5Mv/c (so x 6 cells = 30Mv) must be to high for QLD weather

and Temp set at 120'F.

with your charger, the current setting you have is fine. 30mv per pack is ok. As I said before, depending on if you use a muchmore or another brand, will depend on what delta peak cutoff value you use. For your charger, 30mv per pack (battery) is fine or 5mv per cell.

Leonard.

This may seem a long shot but I think the biggest issue here is that if someone actually gets hurt and sues the club/individual involved, RC Racing in Australia may struggle to continue its existance, as anyone who has been involved in running a club especially in the last few years knows how hard and expensive obtaining public liability insurance is. From this incident it sounds like someone could have easily got hurt, and one incident is all that it could take. Maybe something to think about.

just a question,

I have 4 x 4200's and a much more charger, both bought at the same time and not once have I ever been able to charge these packs at the recomended 03 - 05 mv cut off setting as stated in the manual. The only way I can get a full charge is to use the CTX charge mode set to a linear charge curve with a long lock out (20min) and a minimum 18mv cut off setting. I have temp set to 50c and only on a hot day charging in the back of my car has it switched off because of temp. This way i'm averaging around 4400 - 4600mah per charge which seems normal.
Could it be that my cells are faulty (matched fantom packs) or that the charger is too sensitive ? Because using the normal charge mode (03 - 05mv cut off) all the packs false peak all the way through the charge curve.

Cheers
george.

After reading this forum I have some queries about
my batteries and charging them, i use matched 3800's
and 4200's all are intellect cells, my concern is the readings
I get on the packs after charging i use a duratrax ice charger
only charging at 5amps, temp max 40c, 3/5mv/c very common
and normal charger settings. after discharging the packs which
i only do once every 3/6 months (if i remember). i race every week
sometimes twice a week.
I get some insane readings like 4700ma in the 3800ma packs
and 5900ma in the 4200ma packs.
does anyone get any similar readings or have any ideas as to why???
J-ME

Some chargers have an ove exaggerated readout of what has been happening during charging ... it may be as simple as that

Exploding 4200
 

Glad to hear that I'm not the only one this has happened to. I was getting paranoid with thinking about all the possible things I might have done wrong.
Could not think of any that was the problem!

Charged the pack after equalising to 0.9V/cell on Series 1 Novak smart tray on Ice set at 6Amp, 3mv/cell, normal charge.
Noted on smart tray one light went off very quickly, wrote that off as a below par cell in a matched pack.

After charge (4600 mAh, peak 9.17V no temp sensor but only moderately warm set this pack aside, ready to charge next pack.

After 20 minutes fitted pack to car to use Hudy setup board, setup car and left it in car.

Went to do other things, about 20 mins later heard a loud POP in the workshop, went in could not see anything (body on car) but could smell it.

Finally found cell endcap, black crap all over the chassis and inside of body.
What the........?

I have never had this happen before, sure..... shorted packs, over repeaked batteries, reversed esc connections, but this situation ......NEVER!!!

BTW the cell that let go was the same one that had early lights out on the Novak. Maybe someone can explain what that means...... No other explanation, not shorting out on chassis , not even hooked up to ESC

I'm carefully watching any IB pack now and even more so after reading this thread.... BTW day temp in the workshop was 27 deg celsius...

Lipos may be JUST as safe!

what i dont get is how hot does the cell have to be to explode? my crazy mate had a small fire going, he then thru his old rc plane battery pack in the fire :eek: and left it there! i said he was a crazy f***, but he just walked away and the fire was still burning away. we came back 10min later and the fire had just gone out and the cells hadnt exploded or popped! not one, only damage was the cell's heatshrink covering melted away and thats all. he tried the pack out and they worked, abit :sweat:

so how in the hell did they not blow up after being put in a damn fire!?

i got a new name, instead of calling them "cells". now i call them....... BULLETS!!!! just like the good old western style :D hehe

This from Cannon's post on the previous page;

Another area that a racer should check is that when using a discharger that they get a good contact on ALL cells before starting a discharge. I haves een a acase where contact was not obtained on a single cell. This effectively meant that 5 cells were flat but one cell was still heavily charged. The result when next charged was one cell that overcharged ... and landed 30 metres away.

So lesson is ... when using a discharger make sure you have a good contact on all cells. Some dischargers like the Wave discharger have inbuilt voltmeters. I always put the discharger on to voltmeter reading before discharging to see that I have a good contact with all cells.

Sounds like you had either a dodgey cell or the discharge tray did not have a good contact and therefore not fully discharged. A recipe for disaster.
My best advice is to discharge using your ICE and then put the battery on the smart tray. Than you can be reasonably confident.

My ICE charger tends to false peak where my CDC does not. The ICE appears to be more sensitive, especially with new packs. A lock out of 20 minutes is too long and an accident waiting to happen, especially if you attempt a repeak of a charged pack.

Please correct me if i am wrong, but i think the large amount of false peaking can be attributed to higher discharge currents, higher charge currents and sensitive chargers. The higher you discharge, the punchier the pack and ultimately the battery live will reduce as they are worked harder.