Ep 4200 Has blown up in my face

[big air]

Just been sitting in my out house tinkering with my car when a EP 4200 has just went bang 2 feet away from me, the cells were on top of my plastic tool box NOTHING and i can't stress enough NOTHING was anywhere near them, They were not on charge and were not used since last week, Im lucky the cells did not fire in my direction, Two exploded and have melted my tool box top and set fire to my pit towel. :thumbdown::mad:

[Southwell]

Crap man, thats bad. at least your ok and not hurt.

[ashleyb4]

Ouch

A

[CraigM2610]

thats really bad
atleast it didnt get u

[big air]

I just can't understand why it went up, like i said it was on top of a plastic box, I only moved my gear out there last week i used to pit in my living room and ive got a 12 week old baby :o what if it went up last night or if i wasn't there the whole house would of went up, Im ok apart from my ears are killing me it was like a Bomb going off, :o

[GRIFF55]

That's a bit more to worry about, leaving the cells in my room when i go out and they could still blow up and fire:o:(. Good to hear you wern't hurt, Is there anything can be done for safety??
Did you used to charge at the suggested rates etc?
Cheers

[Mike Hudson]

bet that made you jump like mad, good job it didnt get you though, I always store my cells in their box all locked up so if that does happen they are less likely to fly everywhere and cause injury or damage

[big air]

That's a bit more to worry about, leaving the cells in my room when i go out and they could still blow up and fire:o:(. Good to hear you wern't hurt, Is there anything can be done for safety??
Did you used to charge at the suggested rates etc?
Cheers

Yes mate always charged at 4.5 amps never re peaked as always charged on the day i race, they were taking off the charger at 4200 and always had around 2000 in them when stored discharged equalised left to cool down and charged about 2 to 3 hours later

[neiloliver]

Not on charge or discharge, not short circuited and not used for a week, i cant understand that at all. What state of charge were they in? were they in direct sunlight? (i mean sun directly on them).

N

[big air]

Not on charge or discharge, not short circuited and not used for a week, i cant understand that at all. What state of charge were they in? were they in direct sunlight? (i mean sun directly on them).

N


No they were out of sunlight and its pretty cool where i pit

[JohnM]

I always store my cells in their box all locked up so if that does happen they are less likely to fly everywhere and cause injury or damage

Mine are always kept in their box to, but when I had a set of IBs go bang at the end of 06, they just blew the box to bits!! only sitting 2 feet or so away at the time, thought at first that someone had come in the back door and shot my dog:o, then noticed my Cyclone TC which had been sitting on the cell box was 4 feet in the air!

Took a long time for my wife to let me keep them in the house after that.

Will NEVER buy IBs again.

[dave g]

you need to report this to jim spencer at the brca,

[showtime]

what are the batch numbers on the cells?

be interesting to know if its not just the batch no's already quoted that are potentially critical :eh?:


ARAET, AZCWT, BNCWT, BNDST, BRAET, BZAWT.

edit: just noticed you said EP not IB Doh!

[big air]

what are the batch numbers on the cells?

be interesting to know if its not just the batch no's already quoted that are potentially critical :eh?:


ARAET, AZCWT, BNCWT, BNDST, BRAET, BZAWT.


Where can i find these number??? can't seem to see any on the cells they are the ep 4200 mk2

[showtime]

oops was just editing my post as i noticed you had said EP not IB :rolleyes:

not sure there are any known bad batches of EP's :confused:

[big air]

oops was just editing my post as i noticed you had said EP not IB :rolleyes:

not sure there are any known bad batches of EP's :confused:


This is the second i have known about in three weeks, 4 packs of these cells where bought together, 3 weeks a go 2 cells went of in my mates tt01 at teeside in a race, then these go up today, all matched and bought from the same company, the cells are 5 months old and have only been used once a week

[ben]

where were they bought from?

[ianplimmer]

this is getting out of hand now,think im going to ditch mine and go lipo in the touring car,allready use lipo in buggy

[josh_smaxx]

Bloody hell dude, glad your Ok.

I keep mine locked up in the middle of my hauler in the porch (cold) but im worrying about them now :o Ian's right, this is getting out of hand, make sure you do report this to Jim.

[telboy]

So, even thought the brca have decided on the legal cells for 2008, can they allow Lipo's on safety grounds?

Glad you weren't hurt dude.

[big air]

where were they bought from?

Dont really want to say where they are from because i dont think the problem lies with the matcher, And don't want to start causing problems for them and i dont know if would be in the best interest for the sport to say so, Im defo going lipo now and going to charge them in a metal safe

[ianplimmer]

yeah he's ok thank god but how much longer can we all keep escaping a serious accident

[ashleyb4]

There are 3 versions of EP mk1 mk2 and mk3 mk3 has never been lega mk1 and mk2 have been do you know which version it is.

A

[MK999]

Hoping we can put this down to a freak accident/manufacturing fault in that single batch, but I am starting to get quite worried about the battery situation in general, personally i use GP3700's partly due to budget, but mostly because they're more reliable and can take a lot more abuse (like me being a numpty with a charger and using the wrong profile or something) but the current safety situation on the high performance batteries is getting out of hand. :eh?:

[bigred5765]

thats the first i heard of ep cells going bang i can only say
short circuit can see them going bang like you explained without any reason

[gramey]

:)I bought some of the EP 4200 mk II cells assembled for me by the seller and I was discharging and equalising them before charging them for the very first time. A cell in one of the packs exploded whilst I was discharging it, fortunately on a hard coffee table in my living room and the shrapnel was stopped by my armchair.
I returned the pack to the supplier and he replaced it no questions asked and I didn't have any trouble with any of them after that but it does make you think. I'm running nitro now but I never charged at more than 5 amps and like I said these hadn't even had one charge in them, I was discharging at 20 amps to 5.4 volts.:eh?:

[ashleyb4]

I have stormforce GP4300 I admit i dont discharge and equlise them as much as i should but ive never had any of them blow up on me there over 12 months old now.

A

[xx4-nutter]

i may store mine in the shed now.....

[Northy]

Mmmmmm, get ready for 'the talk' again tomorrow guys...... :(

G

[Lee]

Is that the the "enter stu evans" talk?

[Richard Lowe]

:)I bought some of the EP 4200 mk II cells assembled for me by the seller and I was discharging and equalising them before charging them for the very first time...I was discharging at 20 amps to 5.4 volts.:eh?:
You don't discharge cells when new, they are already flat and equalised.

I don't know how it exploded without you putting any charge in it first, there shouldn't be any energy in the cell to explode :confused:

[Chris Green]

Ouch, this is bad news! glad you are ok.

I'm gonna start wearing safety goggles when I'm racing from now on!

[DaveG28]

TBH, I can't believe the insurers haven't got stroppy about this yet, I mean at this rate someone WILL get hurt, its just a matter of time!

Is all this stuff covered on house insurance by the way whn your at home, eg if my LIPO goes up would I be covered!?

[showtime]

right i'm just about to equalise my IB's

wish me luck :eh?:

http://www.firstdefense.com/html/imagePPU.JPG

[telboy]

I have heard of cells going pop while they are just sat doing nothing before. I may leave mine elsewhere from now on, imagine if something happened while you were asleep?:thumbdown: Not good.

Luckily all my IB's are going soon to make way for new cells.

[gramey]

You don't discharge cells when new, they are already flat and equalised.

I don't know how it exploded without you putting any charge in it first, there shouldn't be any energy in the cell to explode :confused:
:)Well you learn something new everyday, not withstanding that the discharger has an auto cut off, so if there was anything in them it wouldn't have taken them too low anyway. I was just surprised this happened with brand new cells.:)

[GRIFF55]

Luckily all my IB's are going soon to make way for new cells.[/quote]

These were EP's, still it's made me v nervous with all cells!

[Tom3012]

glad no one was hurt!!... my IB's are under my bed at the moment, think i need to buy an air-raid shelter for them!!

anyone want to buy some IB 4200:mad:

[big air]

thats the first i heard of ep cells going bang i can only say
short circuit can see them going bang like you explained without any reason

they came in contact with nothing, they where sat on the top of my all plastic tool box on my pit table 3 feet away from anything else, they where the only thing on the top of my box and have been there untouched for a few days, like i say they just went bang :thumbdown:

[super__dan]

You don't discharge cells when new, they are already flat and equalised.



I don't agree with you there dude, every pack of cells I've ever owned I've equalised off as a matter of course. Most recent cells had odd cells virtually flat but not every one of them. I don't believe it's common for manufacturers to equalise cells off after their final match.

[Northy]

I'm with Dan here.

G

[Richard Lowe]

It probably varies between suppliers, the cells I've had in the last few years have all been flat as a fart :)

[DCM]

does no harm though, to slap them on a tray to make sure does it, I did....

[Northy]

It probably varies between suppliers, the cells I've had in the last few years have all been flat as a fart :)

But that's not gonna do them a lot of good is it? We're not supposed to store them flat........ :eh?:

G

[ashleyb4]

A EP 4200 went boom today at kiddy in there car. Found out he had been charging at 6 amps :eh?::eh?::yawn: It sounded like a gun it wasnt that loud though

A

[Lee]

Cells come partly charged, if you get new cells and they are flat, send them back, they have been sat on the shelf too long.;)


I got an email from schumacher last summer about cells, saying that when we got them we had to build them and cycle tham asap so they dont go down.:)

[twisty]

All these dodgy cells should be recalled somehow.

[mark christopher]

You don't discharge cells when new, they are already flat and equalised.

I don't know how it exploded without you putting any charge in it first, there shouldn't be any energy in the cell to explode :confused:

I'm with Dan here.

G
me too
does no harm though, to slap them on a tray to make sure does it, I did....

yup but the original post discharged em to 5.4 volt so he must have discharged as a pack not individually, there lies the problem, one flat cell would have all the power from other cells dragged though it, then it certainly would go bang

[mark christopher]

:)I bought some of the EP 4200 mk II cells assembled for me by the seller and I was discharging and equalising them before charging them for the very first time. A cell in one of the packs exploded whilst I was discharging it, fortunately on a hard coffee table in my living room and the shrapnel was stopped by my armchair.
I returned the pack to the supplier and he replaced it no questions asked and I didn't have any trouble with any of them after that but it does make you think. I'm running nitro now but I never charged at more than 5 amps and like I said these hadn't even had one charge in them, I was discharging at 20 amps to 5.4 volts.:eh?:
missed this from above post, you should put a 5 min charge in or equalize before trying to drag 20 amps out of cells with unknown voltage, sure i have read this in BRCA info some where

[Chrislong]

missed this from above post, you should put a 5 min charge in or equalize before trying to drag 20 amps out of cells with unknown voltage, sure i have read this in BRCA info some where

Its more common sense, Id never discharge an unknown pack straight off. Put it straight on the equaliser and wait - nothing can go wrong then.

Infact, I can't remember when i last discharged a pack - if I did I would up the cutoff to 6.5v anyway. I tend to just equalise, and if it takes ages, so-be-it, but if a cell goes out straight off, charge for 2mins and equalise again.

[mobile chicane]

I have 4 packs of matched ib4200's one of which has a bad cell which I need to replace but I digress.

I discharge the packs on my charger at no more than 3 amps the equalize them to 0.9v on my novak smart tray I thought that dragging 20A from the packs would kipper them badly.

I only ever charge at 4A for the 4200's and 3.5A for the 3600's

I'll be going to lipo in a few months or sooner if I manage to blag some from flebay :D

[Southwell]

See me next meeting and ill give you a 4200 cell Giles.

[mobile chicane]

See me next meeting and ill give you a 4200 cell Giles.
cheers m8 :thumbsup:

[big air]

I have 4 packs of matched ib4200's one of which has a bad cell which I need to replace but I digress.

I discharge the packs on my charger at no more than 3 amps the equalize them to 0.9v on my novak smart tray I thought that dragging 20A from the packs would kipper them badly.

I only ever charge at 4A for the 4200's and 3.5A for the 3600's

I'll be going to lipo in a few months or sooner if I manage to blag some from flebay :D

I thought the discharge of a pack of cells whilst in a tc or buggy was some where near or over 30 amps, so i think 3 amps is no where near :eh?:

[bigred5765]

but only in a surge not a constant 30 amps

[big air]

but only in a surge not a constant 30 amps


still no where near 3 amps on average, in tc you are either on it or of it ;)

[Lee]

A motor can draw 100A + from a standing start, so 30A is nowt.

I had 12t motors pulling 140A from a standing start on a dyno at times. I dont think its down to capacity, voltages, or even charge rates, its just a dodgy cell that has gone down that people try to charge and it obviously canti charged at 6+ amps upto 10 when racing on road and using IB 4200s.

Just equalise and keep an eye on your cells.

[gramey]

"Its more common sense, I'd never discharge an unknown pack straight off. Put it straight on the equaliser and wait - nothing can go wrong then."

I didn't consider these to be unknown packs as they were supplied by a very reputable company, Modeltech. This is born out by the fact that it was replaced without question. I certainly wouldn't expect Nimh cells to be supplied completely flat, who discharges these cells to 0v or stores them at 0v?

As stated in my previous post 'I didn't have any trouble with any of them after that'.

You only have to look at this thread to see how many differing views there are on how to maintain cells, which regime is right?

"there lies the problem, one flat cell would have all the power from other cells dragged though it, then it certainly would go bang"
This may have been the case or possibly a blocked vent, whatever it was once this cell was replaced the cells performed faultlessly.

To put this into context I had two faulty cells in 6 years of electric racing, one Team Orion matched GP3700 cell which was completely dead, and this one EP 4200 cell. On both occasions the packs were returned and the indivdual cells replaced and no further problems arose.

With the number of cells manufactured worldwide proportionately there are very few failures.

[mobile chicane]

Oh I know that the speedo draws high amps but I'm sure gentle discharge is better for cells than hard discharge.

[showtime]

i just did a google search on "discharge" & you don't want to know some of the horrors i've been exposed to :wtf:

[josh_smaxx]

i just did a google search on "discharge" & you don't want to know some of the horrors i've been exposed to :wtf:

http://www.discharge.co.uk/

Was this it? or was it one of the other links? :woot: :o

[Southwell]

i just did a google search on "discharge" & you don't want to know some of the horrors i've been exposed to :wtf:

O dear god! why o why did i put that into the image search!!!!!!!! :lol:

[showtime]

oh yeah, i went for images too ;)

[Welshy40]

I just can't understand why it went up, like i said it was on top of a plastic box, I only moved my gear out there last week i used to pit in my living room and ive got a 12 week old baby :o what if it went up last night or if i wasn't there the whole house would of went up, Im ok apart from my ears are killing me it was like a Bomb going off, :o

You are one lucky bugger! But I must admit these new cells are not as user friendly like the SCRCs, heck you could twelve volt em before a race and they didnt mind. These nimh are too fragile and seem very dangerous