Trouble with Li-Pos?

[Cyclicscooby]

Never.. Only severe crashes and Muppets on YouTube..

If you use the correct charger, set to the `correct` battery type, balance ( I balance charge EVERY charge ) ,

and don`t over discharge, you won`t have any problems.

As an old Electronic`s engineer, who`s melted many a Jnr hacksaw blade with a Yuasa / car batt, lost count of the mains and car HT shocks recieved, and even took a belt off a 415v 3ph lathe and lived to tell, I respect electricity, and hence Lipo`s, large n small

Luv Chrisie.. xx

[monty2]

Had 2 planes crash both with LiPo's, batteries bent and scrapped eventually but no other problems. I charge them carefully and no issues.

My experience says, look after them, charge sensibly, don't crash and all will be well.

[Wingman]

What do the esteemed forumites reckon on this one? - **LINK** - it's the only case like this I have ever heard of.

[Piers Bowlan]

The worrying thing about the 'trouble with Li-Po poll' is that 2% have experienced unexplained fires. That must translate into a lot of fires considering that most of us use them. Perhaps the next poll should be something along the lines of 'Where do you store your Li-Po's?' 1) Don't use them 2) Garage 3) Garden shed/workshop 4) outside in a box 5) under the bed!!

Edited By Piers Bowlan on 15/07/2014 18:40:31

[Erfolg]

I see the situation differently, it is not 2% of lipos that experience some problems, it is probably less than 0.1%, as most of us will have had about 20 .

Of the 2% of users reporting issues, some have been reported incidents involving others, some have been essentially they felt it was prudent to dispose of a Lipo.

As with so much, the context is important and as well as understanding what a positive response actually means, if anything.

If anything, it seems that some are deliberately trying to damage a Lipo and the results at a individual level are less than impressive, if you want a spectacular result. Perhaps the last link does indicate that collecting a large quantity of Lipos together needs some consideration to the potential hazard that it might represent and then how that hazard can be managed effectively.

[Piers Bowlan]

I didn't say that it was 2% of lipo's that experience some problems Erfolg- that would be cause for concern. Of those forumites that chose to join in the poll, 2% of the respondents (not Lipo' s) answered that they had experienced unexplained LiPo's fires. So 'unexplained' does not include those 'muppets' that bash nails through LiPos and post them on UTube, neither does it include people who accidently leave lipos on the back seat of a car in hot sunshine to combust (has happened). Nor does it include people who slip a lipo into their coat pocket forgetting that their car keys are already in there, thereby shorting out the battery. Unexplained means just that, - spontaneous combustion without human input.

A good point Erfolg you made in that the more Lipo's you have the greater the risk and yes, I would guess that most of us keep all our Lipo's together- makes sense, rather than spread these little incendiary devises around the house/shed! That is until one of them catches fire.

Cyclicsooby says that 'if you use the correct charger set to the correct battery type, and don't over discharge you wont have any problems'. You obviously have a lot of faith (not shared by me) in the quality control involved in the manufacture of these (often Chinese) chargers. Quite apart from the potential for them to malfunction with disastrous consequences the fact that human beings often make mistakes and dial in the wrong type or number of cells can have dire consequences too. The moral here is not to leave charging batteries unattended - unless you want to 'come home to a real fire!'

I am not knocking Lipo's, I will continue to use them, that is, until someone comes up with something just as good but safer!

Interesting poll though.

 

Edited By Piers Bowlan on 16/07/2014 16:09:39

[Erfolg]

Piers

A number who wrote about unexplained fires, did reference others, not a personal experience. How they voted is another thing.

From experience of human beings in a working environment, I have seen the results of unexplained events, where clear evidence of something occurring was very visible. Yet the claim was typically "it just broke Guv, nothing to do with me" or something along the lines of "it did it all by itself, no one was near". Culprits often convince themselves that an accident had nothing to do with them.

Others can be just perverse, something does not suit their agenda, so will say what is necessary to "give a dog a bad name".

I have no issue with goods made in China or the far east in gerneral.I would go as far to say that chargers marketed via reliable retailers, do what it says on the label.

I keep returning to the 70s and the mysterious Nicad explosions that us modellers experienced. Detailed examination of the events often revealed some one doing something rather questionable, from using resistance wire to drop the current, frequently no current detection cut off, or use of a timer and nothing else to detect that the Nicad was fully charged, and so on, More often than not, many problems are down to us modellers and carelessness or abuse, not the fault of the battery, what ever the type.

[The Wright Stuff]

Posted by Wingman on 15/07/2014 17:51:37:

What do the esteemed forumites reckon on this one? - **LINK** - it's the only case like this I have ever heard of.

Well, to prove this type of case was just an urban myth is what I had hoped this poll would tell us. I am out at work all day every day, and away a lot of weekends. The probability that I would catch something like this in time is rather small - I'm hoping the ammo box approach would do its job.

To be brutally honest, I'm not really any wiser after looking at this poll and all the results in it. As I type this, 2% of 563 respondents is over 11 people reporting unexplained / spontaneous combustion. The poll clearly states that when voting, the participant must have personally seen their batteries combust. Scale that statistic up to the number of aeromodellers in the world, and that's a lot of fires!

Assuming people have played ball and voted properly, and also assuming that the respondents form a unbiased sample (do we believe that 95% of aeromodellers use Lipos?), then the statistics show that Lipos are dangerous. By that I mean that the increased risk to property is large enough to be statistically significant compared to the background risk of a fire from other sources (central heating boiler, faulty hairdrier etc). If 2% of people who bought fridges, toasters or electric irons suffered from unexplained fire, we'd be looking at a total ban and public outcry.

To be honest, I rather hope that the poll is not representative, and thus the damning statistics lie!

TWS

[Erfolg]

Perhaps your assessment indicates that there is some bias in the Poll?

Perhaps the details of the 11 unexplained fires are needed? I have read about others having fires, with few details. As we all know, without the detail, from the 11, there is nothing remotely tangible.

Perhaps others have not read the explicit requirements of the voting process?

[buster prop]

I've been using LiPo batteries for years and never had a fire. Some have puffed or lost capacity but burning? No. I always charge at 1C or less and don't usually run them below 30 per cent. Maybe I've been lucky.