can lipo's burst
 

just sold a pack and i got a repot of it being burst!

been doing rc over 20 years and i think i would have spotted that.oh the joys of selling on ebay.

if they were plastic cased may thats split??

They can burst if over charged or over discharged

One went up at the recent TC worlds leading the BRCA Elec TC commitee to make a few changes to the rules for the BRCA nationals.

We all have to use charging sacks now.

If charged and discharged incorrectly they will bulge and eventually pop. I've had a (cheap) battery go when charging at over 1C.

Yes, they can...
 

DCM, in Sweden we have even had reports of LiPos that burt during storage.
According to one owner it was an EFRA approved hard case that was 80 % charged. Others had stored them fully charged.

As for LiPos that give in under use:
http://i319.photobucket.com/albums/m...wulf5/lipo.jpg
http://i319.photobucket.com/albums/m...5/IMG_0049.jpg
Photos are from Groovy Drift

hrmm 1 of mine is starting to bulge a little in a hardcase...

a friends HK cheapo's without hardcase have grown quite a lot and don't hold charge now

They can burst after a big jump and you stand there watching your whole car disappear in a cloud of smoke...

Those pictures scare me :cry: I've only just got some new lipos, are they safe?

Yes, so long as you follow the regulations on charging/discharging carefully.

I personally don't think the technology is ready yet for such high drain applications.

My Lipos are kept in a charging sack in the garage!

Certain sections have decided to use sacks. It's not a brca rule till the agm. If it gets passed every club/racer etc will have to use a bag for charging any Lipo as it will be in general rules.

As for ur Lipo on more than 1s than use ur head and follow the brca guide lines. it users like you who pit others at risk.

We all make mistakes which we learn from and can pass on that knowledge to others. In that instance I just forgot to change the charge amps from one battery to another. A little error like that is all that is required to make one of these things go.

I think your reply was a little harsh.:thumbdown:

Oh and just to add, a number of leading manufacturers quote that their batteries can be charged at more than 1C. See the first line on the 'Features' for this particular item....

http://www.lrp.cc/en/products/vtec-b...c-74v/details/

Could someone point me at the BRCA guidelines?

Here's the latest guideline published on the EB part of the BRCA site:
http://brca.org/BRCA/elecboard/news/...%20pdf%201.pdf

The rumour is that the incident at the 12th worlds was caused by a charger being on the wrong setting.

LiPos are safe unless charged incorrectly or overdischarged.

But if they are mistreated then they do not always just burst into flames immediately. I have had a couple of packs that got overdischarged (faulty lipo cutoff) and they were fine that day and the next, but two days after it had happened I checked them and they had swollen up massively.

In the end, even when one of the cells go up in the pit, they are still safer than an exploding NiMH cell.....

Tell me about it. I remember one going off at our local track. It's like a shotgun pellet.

I do think that the LiPo cell is inherently safe, as long as it is used within it's safe parameters, where as a NiMH would just go...

well yes they can, but I think you would have noticed:woot:, so if your an honest chap I think there is a chance this ebayer has shoved them on a charger, not done things as he should and is now tryiing to get his money back.

Lipos can swell a bit, you soon notice it with soft case flight packs I had a 6 cell swell a little in a T-rex 500.scared the poo out of me:lol:. But if he is saying they have burst and he wants his money back Hmmmm

I'd be asking for an image of this 'burst' pack!

Get him to return it, then after inspection decide on a refund.

i am fully aware of what manufactures say, indeed some say you can charge at 5c BUT the BRCA which govern our hobby ask us to exceed no more than 1c

Don't agree. We had a couple of the IB NiMh cells go up, and all they did was spray debris about the place - one pop and that's it. Since there is no pressure to sustain the reaction, once the can's split that's it.

The recent episode at the 12th WC sprayed hot debris across four pit tables, narrowly missing human flesh, and setting off burns in pit towels. Once the reaction starts, it escalates, not decays like an NiMh. In the case of the WC, we were very lucky that the person whose owned the cell wasn't at his pit table...

Since hearing that someone lost a lot of property (thankfully not any human injury) through a LiPo fault in a starter box that was sat on it's own in storage, I too store mine in a LiPo sack!

Both situations are very nasty, but the LiPo issue is that it is a runaway reaction, whereas the NiMh is a decaying reaction.

I agree that the technology being used in LiPos is heaps better than the later IB cells, that clearly pushed that technology too far. The worst thing was that it was unpredictable, and even following guidelines people experienced catastrophic failures of their cells. In the early LiPo days it was the same with our high-discharge usage - puffing and failures.

As well as the BRCA guidelines, we should buy only from reputable companies that are in the RC game, and not from cheap sources overseas or here in UK. There is no evidence that charging above 1C makes any difference to performance, so why do it - follow advice.

I hope that the BRCA do agree to use of LiPo sacks, since it will allow us to avoid the 'ambulance chasers' should anything happen. This is now a foreseeable risk, and as any HS&E manager will tell you, if you fail to take action to reduce that risk, you will be liable for compensation. There may be many tales of why we shouldn't do this, but in the end the BRCA Exec is going to have to mandate it, or we are going to have to pay considerably more for our insurance premiums!

Use LiPo wisely, in accordance with advice, and sleep easy in your bed. HTH :)

are you fully aware of the consequnces of this?

it would be in general section, so EVERY brca affiliated club would HAVE to enforce that every member using a lipo cell uses a sack.
that would include lipo's in transmitters/starter boxes/ ic car reciever packs and any other car/rc device that uses lipo.

personal ill be voting against it, we in 10th ic use lipo in transmitters/starter boxes and car RX packs the cells in the cars for one are not quick release or visable so how would you enforce who is actually charging a lipo for starters

oh and pete please define a lipo sack and prove to me its going to stop the fire as if u tell me to use one and it dont work then ill sue ur ass:p

Whats the difference between the Lipo in my phone and in my car?

Does that mean I need a Lipo sack for my phone, and laptop?

I have to agree with Mark, unless the LiPo bag conforms to a rule, so that you can garauntee that it will contain the combustion if a cell does fail, you just open another can of worms....

its deemed safe as you have or are suposed to have a dedicated charger

they must be deemed safe as most of us keep em near our balls (phone not lap top) :woot:

rc lipo any fool can plug any charger in to them

bloody hell....... cut and pasted to keep :thumbsup::woot:

hee hee :thumbsup:

deleted

if my macbook gets low on juice it will put itself to hibernate to stop the battery voltage dropping too low

also it balances itself every charge to prolong the life

i feel it should be left to individual sections as it has been till the agm.

lipo is lipo but sections use them differently
IE ic use them for starter box RX and TX, yet elec TC, buggy, 12th etc use them as thier motive power (more strain on pack and charged every (other) run)and TX once a when ever its low

If we are going to 'general rules' Radio Transmitters should only be used with the cells that it has been designed for, from memory.

In the end, there is some 'risk' involved, and you can't 'mandate' for numpties without the regular and experienced feeling that they are being unduly regulated. Personally, I can't see how a LiPo bag makes the use of LiPo's that much safer anyways.

It is a motorsport, motorsport IS dangerous.

Mark,

I dont know which BRCA Exec meetings you have been attending, but I would be interested in hearing where you heard the "EVERY brca affiliated club would HAVE to enforce that every member using a lipo cell uses a sack".......

Seriously, where do you get your information from?

I think, when it comes to the Liability insurance, if there is a general rule, like separating the track from the pits, etc, they are not things you can choose to ignore on a day to day basis, whereas section rules, clubs can choose to use or ignore as they see fit.

Everyone has a special case, and so it will be decided by the Exec. My definition of a LiPo sack? One that will contain the debris from a LiPo fire and prevent it being shed on the local area in an uncontained way. You cannot stop the fire, you can stop the debris from being ejected from the fire. I think you'll find that this has been adequately demonstrated by several of the manufacturer's who sell such sacks.

Mark, who said you had to remove LiPos from cars or starter boxes? We are trying to contain the debris, so what's to stop you wrapping those LiPos in a way that will prevent the debris from being ejected? Isn't it the case that if a starter box is steel, and that the LiPo could be contained within its own box within the main box, also steel? And isn't it the case that the receiver LiPo could be contained in its own 'mini sack' within the receiver box?

If you'll forgive the pun, you guys need to accept that we have to do something, and start thinking outside the box!!! (groan!) The problem is to contain any debris, not get the LiPo into a sack when charging. Use your imagination. I wouldn't want to keep taking batteries in and out of sealed boxes every heat either, but that doesn't mean that I would ignore what is now a foreseeable risk. Put your rude typing fingers away and get out your brain!!! ;)

The can is already open, that's why we're here. The thing we need to do is close it as best we can (groan, another bad pun!!) and demonstrate we have taken some action to reduce the risk. If we don't so it for ourselves, a large claim against us will do it for us. Why wait for that to happen... why not take control of our own destiny?

Look at the recent claim we have had to pay that has led to a complete re-appraisal of the way we set marshals, and has led to a large amount of work for every National. We can moan all we like, the fact is we have to do something, or face having it done to us. I prefer the former...

My only concern, is that with the LiPo sacks, as there is no 'designed' test for them, I think it could lead to more problems than it could solve when it came to a claim. In as much as I have seen people use home made LiPo sacks for one, secondly, if there isn't a test to ascertain their ability to withstand the heat/flame/chemicals of a burning lipo, how do we measure/determin ones that are suitable, and ones that are not. Then, when the cells are in use, how do you then contain a failure...... it is a can of worms that, when opened, your gonna have a struggle closing it.

Not that I am saying that your wrong, but how do you make it right?

ok fact form one sections vice chairman to anothers chairman

if it goes into "general rules" ALL BRCA affiliated clubs have to abide by these "general rules" as written in the handbook ie rule 8 All events are to have a first aid kit. now this allpied to ever brca affiliated club at any of thier meetings.
Oh and my information comes from Jim Spencer (incase you dont know him he is treasurer of the BRCA and is on the Exec commitee) and is 100% correct, if you doubt it call him and ask. i often call him to make sure im correct before i put brca fact out.

SO...... ill reply as your a chairman of a section , why dont you know that Chris? i would ask you to read general rules point 1 and the first sentance above the point1

I look forward to your responce!!

Mark

exactly, someone has read the book ;)


pete all starter boxes are full of holes some more than others, some have open bottoms and are a box in terms not structure.

most IC circuit cars do NOT have a box for the RX pack, infact most sit under the fuel tank and are a snug fit with no room to wrap them in anything.

so you would have to put the whole car in somthing, which is hardly convienient.
so on both cases no its not the case......

DCM, where risk management is concerned, the object of the exercise is not to make it right, but to move forward in light of facts. The problem with most H&S regulation is it is just that - regulation. It is not Law - a definitive statement of what is, and is not, allowed.

When H&S Regulation is released, it is interpreted by professional H&S risk professionals and that interpretation is what we implement. That's why we get these *cough* recommendations that all makes us smile - banning conkers in the playground, or speed bumps in the road. However, once something does happen, and the matter goes to court, a judge will make a ruling. This becomes a re-definition of the Regulation, and we all go back to ensure that we are doing something better, or different, to further reduce the risk. Piper Alpha, and its impact on offshore oil platforms in the UK (at least!) is one such example, as is the Herald of Free Enterprise and its impact on Ro-Ro ferry design. Before those accidents, the risks were assessed and the safety systems were implemented as the standard. When the proved inadequate in a court of Law, the systems were changed and/or improved to make a new standard.

So, what we need to do is to set a standard. We might suggest that we conduct a test, informed by experts, that shows that a certain design will contain LiPo debris, and then set that standard for LiPo 'sacks' or starter box cases or whatever. That would show we had tried to mitigate the risks, and give us something to demonstrate our responsibility. If our actions are shown to be insufficient in a future incident, we have to update our mitigation. Why is it so hard to get people to do something, or is it just easier to sit there and type out some excuse for staying on our arses typing into computers...?

If you want this to go away, it won't. If you want it to be suitable for your class/Section, start thinking and acting, before someone does it to you. Just my 2p...

pete im sure the eb were or are looking at what constitutes a lipo bag, but not all sections use eb rules, though i would hope most will follow the guide lines they set out.