Another instance of non-abused hobbyking battery failure

[neptronix]

http://www.elmoto.net/showthread.php?1201-Turnigy-battery-mishap&p=12768#post12768

About three weeks ago I had a small 1800mah 3S pack blow up on my charging bench. No reason for it. BRAND NEW pack. Charging at 1C. I managed to knock it on the floor. All it did was scorch my charger and put smoke crap everywhere.

TWO DAYS AGO I opened my Lipo cabinet in my warehouse/shop to get some packs out. I noticed a strange sticky film on the packs...THEN I SAW IT.... a 4S 5000 40C Turnigy pack, again, brand new and hadn't even been charged, had blown up inside the cabinet which holds about 50 lipo packs! It had to have happened when nobody was there.

Guys, it looks like hobbyking's battery quality may be going downhill. When i got into lipos, you could expect a 10% dud rate, but that was just bad cells, not these ones that will puff up / vent gas / vent flame on their own without any use; this seems to be a new phenomena that i have heard about in 2011..

If you are going to buy hobbyking lipo, cycle the packs immediately upon recieving them, in a safe and fireproof area!!
Always assume a pack is a defective firebomb until proven otherwise!!

If you need a flame proof bag, hobbyking, progressiveRC, hobbypartz etc do sell one. I would charge new lipos in such a bag if possible.

I have bought a total of 13 lipos and already had 1 puff up on me with no cycles, it was a 20C turnigy that had been sitting for 3 months. I set it outside and it deflated itself with no flames.

My other lipos have performed flawlessly after separating the duds from the studs.

Once a few cycles are on the pack and there is no puffing, if you do not abuse a lipo ( overdischarging cells below 3.0v, overcharging above 4.25v, discharging at higher than their C rate, or charging at higher than their C rate ), it will be very safe and last you quite a while, but never ever assume a pack is good.

Here are two instances of lipo fires on the forums from non-abused packs.

http://endless-sphere.com/forums/viewtopic.php?f=14&t=29256&hilit=john+in+cr+lipo+fire

http://endless-sphere.com/forums/viewtopic.php?f=14&t=29256&hilit=nasty+lipo+fire

 

[Red_Liner740]

naah, what i think is happening is more and more people are using HK lipos and therefore it may seem more failures are occuring, but its actually a game of numbers

more ppl = more chance of someone having an issue, but the failure percentage is probably the same.

Someone should really do a poll of Lipo users and whether they've had a lipo pack failure or not.

 

[neptronix]

A poll on this forum will not give you a real number.There are only so many regular readers and people that participate.

Sure, more people are using it, but a failure like this is not acceptable no matter how low the numbers are. That's still one person's house potentially going up in flames. A lot of those packs were recently bought, 2-3 years ago this was unheard of.

For the record, i still like lipo. I will still use lipo until a suitable alternative is found ( light weight, small size, > 3C rate, affordable etc ), but i think it is imperative that people know the risks before investing in these kinds of batteries.

 

[AussieJester]

Someone should really do a poll of Lipo users and whether they've had a lipo pack failure or not.

Safe ?

KiM

 

[Doctorbass]

Just an idea.. but .. does it might be possible that the pack that are shipped by airplane could be affected by the altitude ?

I mean the pressure drop alot at 40000foots altitude.. and the pack are not in the pressurized cabin... and apparently the temperature range also shift alot during the transport in airplane!

Doc

 

[snowranger]

Good thinking. It is likely that shipments from the US warehouse have never been in the air since they go by sea and land. I still got one dud out of 8 for the turnigies.

 

[wesnewell]

Are all, or most of these failures using turnigy? I've ordered 5ah 15C Zippys and haven't gotten a dud or puffy yet. 28S in 4 5s and 2 4s.

 

[neptronix]

One was a zippy. The other was a turnigy.
I had a dud cell in a zippy and a puffed out turnigy.

 

[itchynackers]

Out of 30 5s 3ah zippy's...

One cell puffy upon arrival. Removed and discarded.

 

[Spacey]

Out of 6 x 5.8ah 8cell Turnigy packs I had 3 of the packs with seriously low voltages i.e 1.3volts, had to replace them by hacking up some spare packs I bought.

Still have a low cell but it is parralled with 2 other packs so isn't too bad. Wish I had gone A123 with Cell man...I still might when money gets better. I have to charge and leave the bike in the house as no garage but will be moving to a house that has one soon.

 

[EVDragRacer]

Just an idea.. but .. does it might be possible that the pack that are shipped by airplane could be affected by the altitude ?

I mean the pressure drop alot at 40000foots altitude.. and the pack are not in the pressurized cabin... and apparently the temperature range also shift alot during the transport in airplane!

Doc

All my 140 Turnigy nano-tech 5S packs were delivered by air-freight, not one bad pack. I had a few that needed to be cycled and balanced, but all are okay and within specs. I have beat the crap out of these cells pulling more than 4000amps from my pack, and they still kick AZZ!

http://teamhaiyinevracing.com/photoalbum.html

 

[Starson]

A poll on this forum will not give you a real number.There are only so many regular readers and people that participate.

Sure, more people are using it, but a failure like this is not acceptable no matter how low the numbers are. That's still one person's house potentially going up in flames. A lot of those packs were recently bought, 2-3 years ago this was unheard of.

For the record, i still like lipo. I will still use lipo until a suitable alternative is found ( light weight, small size, > 3C rate, affordable etc ), but i think it is imperative that people know the risks before investing in these kinds of batteries.

It's not a poll, but el_walto posted a compilation of RC lipo failures and their causes from sourced information in another thread. I like this list because the use of lipo for ebikes is relatively new, and there is just more history from a larger user base in the RC world. Their will be differences in the application and use, but it seems to me that this info is eye opening. http://endless-sphere.com/forums/viewtopic.php?f=14&t=27494&p=397911&hilit=+rc+lipo+failure+dog#p397911

Gary

 

[liveforphysics]

Contaminants in manufacture.

That's my guess.

 

[neptronix]

starson: RCGroups is a great place to get info on this type of thing, thanks for pointing out that thread.

spacey: You have had the worst luck with lipo out of everyone on this forum that has reported. Perhaps you have a curse

LFP: That would make sense. Especially if their 'clean room facility' is not so clean. Dust filters can cost bezerk amounts of money and need replacement quite often. That dust/junk can get into the cells easy.
Or they are using lower grade materials maybe.
Who knows.

You get what you pay for. Lipo is a cheap way to get into eBikes. It's super cheap to start out with 5AH and go from there.

The upside is that if you invested heavily in lipo like myself, and get turned off by it, the latest and greatest cells ( lithium + nickel / managnese / cobalt in various forms ) just so happen to be 3.6-3.8v nominal and work great with all the lipo equipment

 

[Pure]

This guy was using LiPo for RC use. With as much abuse these cells recive in the RC world I'm suprised we don't read about this sort thing more often. I personally take it as a testament to just how much these things can handle without going thermal. This makes sense if you look at the batteries as volitile equipment to begin with.

Edit: I've seen what could possible be worst case of what a LiPo fire can do. About 5 years ago I was working for the IT dept of a large consulting firm in DC. They used LiPo for their battery back up for their servers and telecom systems. One day for no reason a whole room of LiPo went thermal. The damage was extensive to say the least.

 

[dogman dan]

Bottom line, we do have to be carefull where we store this stuff, etc. Another reason I seriously disagree with those who more or less permanently attach the batteries to the bikes. My way is sure a pain in the ass, but every time I charge them, I have a chance to do a visual inspection FWIW. All my lipo stays in my fireplace these days.

 

[auraslip]

Another reason I seriously disagree with those who more or less permanently attach the batteries to the bikes. My way is sure a pain in the ass, but every time I charge them, I have a chance to do a visual inspection FWIW. All my lipo stays in my fireplace these days.

Well.... Is it the case that after 20 or so cycles we can assume a battery will perform safely for the rest of it's life as long as it's not abused?

 

[knoxie]

Another 1, I agree with Luke, I think this is a contamination issue maybe? dont forget the Zippy and Turnigy batteries are made by the same company just make that clear if anyone thinks one has preferable levels of safety based upon the brand of packs that have failed then this is a misnomer.

Treat any brand of any type and capacity the same and you wont have any problems

 

[Emoto]

Just an idea.. but .. does it might be possible that the pack that are shipped by airplane could be affected by the altitude ?

I mean the pressure drop alot at 40000foots altitude.. and the pack are not in the pressurized cabin... and apparently the temperature range also shift alot during the transport in airplane!

Doc

All my 140 Turnigy nano-tech 5S packs were delivered by air-freight, not one bad pack. I had a few that needed to be cycled and balanced, but all are okay and within specs. I have beat the crap out of these cells pulling more than 4000amps from my pack, and they still kick AZZ!

http://teamhaiyinevracing.com/photoalbum.html

Well so far there has been no probs with turnigy in our rc group, persionally i abuse my 25c 3s daily pulling up to 50 amps, ive under/ over volted them, have crashed so hard ive bent them more than once , and just bend them straight, i wouldn,t condone this on a ebike of course :wink: .

Check these out http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=17271

 

[LiFe]

All my 140 Turnigy nano-tech 5S packs were delivered by air-freight, not one bad pack. I had a few that needed to be cycled and balanced, but all are okay and within specs. I have beat the crap out of these cells pulling more than 4000amps from my pack, and they still kick AZZ!
http://teamhaiyinevracing.com/photoalbum.html

Yup, the folks who know better than to stuff a herd of lipo's into a car are waiting for the inevitable. And where you'll point your finger Ron.

These ES ebiker wanks have a much smaller bomb to worry about.

How many NEDRA guys are packing their drag cars with LiPo's.

I'll watch the ecedrag posts...

 

[LiFe]

Contaminants in manufacture.

That's my guess.

No shit sherlock.
At the prices RC guys are wanting, these cells are probably assembled in a Guangzhou dirt floor sweatshop.