Another LIPO FIRE ! Be careful !

[Bazaki]

A friend of mine his Ebike is totally destroyed by a Lipo fire.
Full Suspension Bull Sugar Max Team XTR with 66,6v 10ah 18 fet controller Crystalyte HS Cycle analyst etc etc.

My friend was Bulk charging the 18s 2p Zippy's in his garage, after a while a neighboor rang the door bell that there was a huge amount of smoke getting out of the garage.
My friend opened the garage door and the rest you can see above.

Well, here is what I think what happened :

December 2011 the Ebike got his last charge, my friend installed a GPS tracker to track it down when if it ever got stolen, this GPS tracker got it's own battery with a few mAh and got his main power from the 18s2p pack by a DC-DC converter (72v->12v) After three months DEC-JAN-FEB, the GPS tracker sent a text message ( Battery low ) so friend is charging the bike without checking his cells. I'm sure that some cells did drop to a way way way too low voltage like 1v or 2v or less. Some cells were probably dead and the rest of the cells got way over the 4,20v per cell and caused a fire and later a complete meltdown.Luckily nobody got hurt, my friend could remove his car and by doing this he got a "black" long but he is fine now. If the neighboor did't drove by...............


Just want to share this with you people, don't get lazy, more and more people start to use RC Lipo's for their Ebike,incl me and some friends.

Just be careful out there !

[Bazaki]

viewtopic.php?f=31&t=36414

I want to advise all my ebike friends and people here the above Complete Hobby King Lipo Protection Kit !
This kit would have avoided the fire.

[Ypedal]

Ugh.. that " was " a nice bike...

Glad he's ok.. and all his other stuff.. dirty but intact..

[Hugues]

Doesn't feel good to see this.
Luckily no one got hurt.

Just for me to understand:
- battery pack did not have BMS ?
- by bulk charging , you mean just applying pack voltage without any kind of cell monitoring ?


If so, that's looking for troubles in my opinion, especially leaving the cells for 3 months with a small current drain ....

[Ykick]

Yeah man, RC Lipo ain't exactly plug and play!

[mxer]

Sorry to see this, and yeah that was one tasty bike Sounds abit off, but thanks for sharing as we all will "measure twice cut once" and reset our pahaps complacent selfs after a while, These pic's show real life and make you think!!!....

I still religiuosly check every cell before charging and glad it is a habbit i can't get rid off, I have tried but just coudn't do it


Hope you get things sorted and have life back to normal as soon as ......

[ohzee]

Yea also glad it was not worse.. he owes that neighbor some beer.

I am pretty paranoid with my lipo and monitor it very closely when doing anything.

These kind of posts are needed just so people realize what can happen thanks.

[Bazaki]

That indeed is the message here, people including myself get lazy and that's when the danger starts.

[o00scorpion00o]

This is down to pure negligence and nothing else !

It's people like that that give lipo a bad name

I don't monitor voltages every time I bulk charge but that's ONLY when I don't run the battery down to low, if I do, then it's balance charge only!

[flathill]

http://endless-sphere.com/forums/viewtopic.php?f=31&t=36414

I want to advise all my ebike friends and people here the above Complete Hobby King Lipo Protection Kit !
This kit would have avoided the fire.

Are you sure? What happens if the cells drained so low some of the cells reversed? In this case they would have could have caught fire before any cell hit the hvc. As I understand it the lvc only cuts the throttle but does not prevent a parasitic load from draining a pack to 0

[NeilP]

So he let the pack go flat for months and then tried a bulk charge...sorry for the loss,


December since last charge ...and with it powering the 72 to 12 DC-Dc convertor and then plugging in to bulk charge just plain....I'll say no more...... but either he knows nothing of the possible dangers and use of Lipo and was badly advised when he built the bike or is just taking stupid risks.

I have had various people ask me about batteries, and my pack 20s4p..compare it to a similar capacity Headway Headquarters pack...twice the size. I them show them how I have to charge my pack, followed by LiPo fire youtube videos, and maybe purposely overcharge a LiPo foil pack cell till it flames out.

Either he did not know the dangers (was badly advised to start with) or is just ...well I do not want to say "dumb"...but can't think of better word.

Or maybe he just knew the risks...and thought he would take a gamble..but not checking cell balance first...stupid

[kfong]

Ebike fires are adding up. Too many things can and do go wrong. Lipo's are not something you can get lax about. Bulk charging is not something I plan to do or recommend ever. This is like using old RC chargers without balance ports. There is a reason the RC industry have gone to balance chargers. When an RC charger sees a problems it goes into shut down and warning mode. It would of seen this problem. There are lots of lipo fires that happened in the RC forums each year due to all kinds of reasons. Having a lipo fire with an ebike however, is not something you can dismiss because the packs are just so damn large. You should have a system that can disconnect the packs if they go too low without some tiny drain due to the BMS(battery murdering system) or controller that doesn't completely shut off. One of the reasons I built a smart switch. I wanted a total disconnect when battery reaches LVC to protect the cells and an auto shut off if I forget to shut down. I only do balance charging with a good RC charger, Hyperion's are what I currently prefer. This pretty much takes care of most mistakes. Wiring shorts and crash damage is something else you need to watch out for.

[Bazaki]

Dumb or not, we can not expect that all people will monitor the cells (I do). People search the web how to build an ebike, buy some HK Lipo and ride with half the knowledge they should have about Lipo.

Those people need to be warned and these topics show the consequences if mistreated.

Even the lvc hvc charging kit is not foolproof. But it is a good start !

[liveforphysics]

Its kinda crazy to think about, but a drain of only 10mA, which is virtually nothing, drains 7.4Ah per month!

Over 3months, youre draining 24Ah.

[kfong]

The problem is with ebikes, people tend to add all kinds of accessories. Such as what happened in this thread. GPS running all the time, I bet the current drain from the DC/DC was rather significant. Then there is the problem of running your packs down to empty and leaving it sit for a while. Won't take much to drain it past LVC with such little capacity left.

[dogman]

Ignores the pack for three months, then throws it on a bulk charger and walks off.

[rojitor]

Damn! Things like this make me think about balancing the pack more often. Lipo is not for procrastinators....

[amberwolf]

It does not currently do this out of the box, but Method's solution could be setup to use a charging cut-off board to disconnect the pack entirely from the bike upon hitting LVC. It might require heatsinking the FETs on there, though.


Regarding this fire...as has already been pointed out, not checking the votlage after letting them sit and even after getting a low power warning from the GPS....

I assume the GPS would give the warning only after it's own internal battery was low. Thus, that meant that whatever was powering it's charger must be such a low voltage that the charger can no longer output enough voltage to charge the GPS. If it's a typical AC adapter type, then it can probably run down to 24-40VDC, possibly even less if there's not much current load on it (though it may require >40V to *start*).

it's possible that the charger would continue to drain power even when not outputting enough power to charge the GPS, too, draining the pack completely after that. If the controller on the bike or anything else was also still being powered by the pack, that would also continue to drain it; could easily run it down to zero volts over that time.

So the pack was probably drained to completely dead before that GPS low battery warning was ever sent.

[John in CR]

The moral of the story is ride your ebike every day.

Though I cringe with every RC Lipo event because I feel it harms the cause, to my amazement a google search of "Lipo Fire" doesn't come up with an ES hit until page 2. They're so prevalent with the RC guys that we're able to stay out of the headlines.

[mvly]

This is why I always balance charge and always disconnect the battery from everything when I am done with it everyday. I never allow it to do anything funny. : )

[FastDemise]

If you think that the battery pack total voltage fell so low that the converter wasn't able to maintain even 12V. My guess is the battery was trash long before the GPS sent the alarm.

[NeilP]

Hey Bazaki, first off, I must apologise if I am wrong, but I have been thinking this and feel I must say it, so sorry if I am wrong and pointing finger in wrong direction...but

Your friend, is he a member here on the forum? Does he read it? Or any RC or E-bike forum and
did he build the bike by himself or with help from you or someone else?
If he is not a forum member or other regular RC or LiPo user, then as far as I can see the finger of blame here points at who ever helped him build the bike. If he used LiPo totally of his own choosing without any help from a third party, then it is his own fault. Otherwise whoever helped and advised him should shoulder some of the blame

Since I have been involved in E bikes, alittle over 1 year now, I have helped build 4 different bikes for others, plus 3 of my own. 5 LiPo powered, one Headway, and one dewalt drill packs.

To every person that comes to see me about a bike, first I let them ride mine on low power, then if that does not scare them enough, on full 100 volt 80 amp high power.
I then show them what I do to charge my pack. usually followed by a deliberate overcharge and burning of a dud LiPo cell or two, plus You tube videos etc

LiPo is not for most people, and it sounds very much like your friend had no idea about LiPo at all to do what he did. I get worried enough leaving my packs alone, disconnected from the bike or any current drain for a couple of weeks. To leave them that long is just plain stupid....or totally ignorant of the facts of LiPo use

Again sorry if the build had no input from you, but it is down to all of us to help prevent this happening on Ebikes and a house getting burnt down and someone killed. What would have happened if the neighbour had not seen the smoke, fire had started at night etc etc

[neptronix]

Ignores the pack for three months, then throws it on a bulk charger and walks off.

LOL, yup.
Someone did not get their education before they got into this whole, running a battery without a BMS thing.
Any other chemistry may not have blown up, but it would have most likely been a bookend at that point. Maybe he would have just got a smoke show.

Over discharge, then charge seems to be responsible for the majority of RC lipo fires.

Always happens in winter when someone parks their eBike for the season and has a parasitic load, usually being a BMS.
Then we get tons of threads about dead China lifepo4 batteries.

There is a recent PR Blitz against Tesla Motors because this overdischarge happened to some of their early roadsters.
The batteries got overdischarged, then 'bricked' by the BMS... to prevent fire during charge.

http://green.autoblog.com/2012/02/22/tesla-roadster-facing-brick-battery-problems/

^-- read this thread and see how many people are confused about it..

It is pretty amazing how common this problem is. Then again, early cars were not designed to have their oil changed, and it took a while for people to wonder why their internal combustion engines were seizing after 10-20k miles.

I suppose we'll have another few hundred winter battery destruction threads till the public figures it out

[Bazaki]

Me and my friends are riding RC lipo on ebikes for a long time, this friend " joins" the club and ofcourse all our knowledge is shared with him. So he knows all about the cells as much as we do. He knows the lipo fire stories, and every situation that can cause a fire. Repeated over and over again, he also fully understands and is also reading this forum.The friend is a grown up 40 years old man, a he just made the mistake to leave his pack drained completely empty. I don't feel responsible, I do feel sorry. But when another friends wants to ride an ebike and asks me what to do I will advise them to buy a plug and play lifepo4 or other ebike batterypack.

[o00scorpion00o]

How many of us use lipo and know the risks and have never had any problems ?

Would us that know about lipo risks put our lipo on bulk charge after a few months in the shed without checking cell voltages ?

I wouldn't even put them on the balance charger without checking !

This chap will go around telling everyone now to avoid lipo or it will explode in a bg fireball.

There is no way I would part with my lipo. Lifep04 is too heavy and bulky and ones with decent c rates are way too expensive! Until something better comes along with twice the capacity of lipo and half the weight, so looks like its good old LIpo for another 5+ years or more as there doesn't seem to be any progress in battery development at all and it's looking bad. All the newer battery chemistries we were promised years ago have never come to be.