Exactly the reason I am trying to find out the FACTS of what happened is so I can put something out to the clubs through the Interclub committee so members can be advised.

No one is trying to blame anyone

Quickly reading thru the posts here.

Some revelant points to chargeing have been brought up and should be adhered too I guess some of us(Battery Guys) just do things that we assume others do and take this for granted that every one knows what to do and what not to do when chargeing/dischargeing these cells.

As Greg and others have pointed out.YOU MUST READ and UNDERSTAND all instructions that are provided with anything one purchases or uses. If in doubt ASk..

Picking up on two points here that would be revelant to the outcome of both these incidents thathave occur and i couldnt see where anyone has mentioned this..

Yes your mv settings are important BUT also When a battery is charged it builds up heat which changes characteristics of the materials used in its construction.. In simplicity the hotter it gets more gas is generated until the pressure build up causes it to vent( In most cases this venting doesnt occur and when the cell starts to cool the gas is absorbed back into the cell material.

When a cell has charged the internal heat is still greater than the exterior, therefore it will still heat up after charge until this is dispersed threw the outer case.

The battery in this case as stated was placed back into a non conductive battery case{was this a foam lined box( as was the other pack that expoded)} This alone would act like a minature oven and most likely generate more heat again...Causing the battery to produce excess gasses than what it would if left on a bench in a ventilated area. This would in effect creat a pressure container??


Not only do we need to be educated in the proper use of Chargers/dischargers but in general the proceedures of manageing the cells after the charge process.This also can occur in reverse with severe discharge with high loads(current draw)

this is why i asked the question.

we have all got bombs ready to go off.

you can read all you want but if you ask the right question from the wrong person you will get a bad result.

how many chargers are set wrong.
i saw at least 5 muchmores set at 18mv on sunday ??

How Many More Chargers are set to be BOMBS

Just to clarify, with the Muchmore CTX chargers only - the delta peak cutoff setting is for the entire pack and not the individual cell like most other chargers. As like what others have stated before, with the MuchMore CTX chargers, only use 03, 04, 05 and 06 as values and do not go higher than this. As a guide, use the ambient temp of the room as a guide if the ambient temp is low (under 25'C - ie. night time racing or a cool day) then use a higher value like 05, 06 if it is above 25'C use 03 and 04. Make sure the thermal sensor is used and the temp cutoff is set to 47-48'C.

These are just guidelines which when I was using MuchMore CTX Chargers worked quite nicely. I hope this helps.

I am glad to hear that no-one was hurt or injured by the exploding battery.

Leonard.

In my opinion charging in a battery box or any kind of box is crazy.

Surely natural air circulation around a battery pack is a must if you dont want it to overheat. Packs already get hot enuff as it is during normal charge at 6 Amps and the foam in a battery box will act as an insulator to hold more heat in the cell.

I wont even put a pack in the box after charging to ensure it cools down properly.

IE i charge a couple of packs before heading to racing to ensure i am ready to start, so when i travel to the track i usually put them on the floor of the car to make sure they are still able to cool down.

Anyway just my opinion....

so setting the temp probe to 48 degrees, what happens on a 40 + deg day
when the battery will get to round 60 deg u end up with an undercharged pack. just stick to 3mv setting and set temp to 60 deg havn't had a problem with mine using this method

Dont leave your batteries in the sun or charge them in the sun. Make sure they sit in the shade

CANNON.

To avoid the heating problems and venting blah blah blah, would placing the packs on an ice pack or in a cool esky do any damage to them. This would be before charging them and maybe if a hot enough day, whilst doing the intitial charge prior to re-peak

The reason I asked is I placed one of Sonny's battery packs (Johnny's) on some ice rapped in a cloth I had left over from a drink. The batteries when I noticed them were at about 55 deg, after placing them on the ice they went down to 44.5 and stabilised, this is whilst charging them. They were also placed behind the Much More charger so the fan was also blowing on them.

As for the comments regarding the IB World cells, they do seem to get stupidly hot as the pack mentioned above was being charged right after the explosion and this pack was getting very hot also.

Thanks in advance

Just one note that i dont think was mentioned. After charging, the batteries keep generating heat for up to 30 mins after the charger has been disconnected. I would strongly advice against putting the battery into any type of storage container for up to 1 hr to ensure the batteries chemical reaction has finished.

The charge in a rechargable battery comes from this chemical reaction... an example of this can be as: my charger is set to 47 degrees temperature cut out, my charger sensors this temp and shuts down the charger. After about 5 mins the pack temp can be upto 58 degree.... mmm up by 11 degrees.
Outside cooling ie: fans should not be used to cool the battery as this only gives a false temp reading on the outside of the battery. The temperature is generated from within, thus this can lead to problems.

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.