E-scooter and E-bike fires 1

[Murph 9000]

That would make sense; a dead battery has not much energy to do much of anything. So, just need to discharge the batteries before shipping; easy-peasy

Nice idea, but that significantly increases the risk of a catastrophic failure from the battery. An over-discharged Li-ion cell dissolves the copper electrode, which then re-plates on charging with a significant risk of creating an internal short.

Fun fact, around 28 typical 18650 cells have a combined nominal energy of around 1 MJ, the same as a stick of Dynamite. The total energy of a Li-ion cell is actually significantly higher than nominal due to the need to stop discharging well above the zero point, and the chemical energy in the electrolyte. A Li-ion battery pack can't release its energy quite as quick as Dynamite, but it can do it quite rapidly in the right circumstances, and the total energy is there.

 

[Sparweb]

Fun fact, around 28 typical 18650 cells have a combined nominal energy of around 1 MJ, the same as a stick of Dynamite.

So does a 40 Amp-hour lead-acid battery. So does a 40 Amp-hour Ni-Cad, too.

Are we all talking about "how lithium batteries fail" or about "how all batteries fail"?

Recharging Ni-Cad with the wrong charger can cause it to catch fire or explode. Sound familiar?
Unregulated charging of a lead-acid battery will cause it to vent gases and swell. Sound familiar?
Shipping flooded batteries containing electrolyte can risk cargo fires, and is illegal in many places. Sound familiar?
Overheated Ni-Cad and Lead acid batteries will vent gases that can be explosive. Sound familiar?

Sometimes it sounds like everyone is discovering all the problems and headaches that come with batteries, they're just named differently today. Actually, people have lived with messy batteries for decades (centuries!) and there have been lots of problems, injuries, fires, and worse, along the way. Lithium is just the newer "better than awful".

Spilled electrolyte is toxic and a serious health hazard. Spilled electrolyte is corrosive enough to destroy many metals. Oh, wait there's no sulfuric acid or potassium hydroxide in lithium batteries...

Repeatedly cycling a lead-acid to full discharge causes sulfation, high resistance, and overheating. Oh, wait, a lithium can go full-cycle without damage...

My point is this is way better than what we used to have. All these convenient and fun new technologies are IMPOSSIBLE without lithium batteries. That means that LI is exposed to vastly more accidents and abuses, including the design flaws and lousy installations that get people into trouble, because they are just so COMMON everywhere.

Today, everyone in the world has a lithium battery in their pocket, with enough energy in it to burn their skin.
Imagine if everyone actually had a lead-acid battery in their pocket (ignoring the weight penalty) then you can't imagine the nightmare of skin burns and poisonings from all the chemical spills that the "state of the art" of lead acid actually offers. We don't see that filthy state of the art because lead acid batteries are vastly less versatile than lithiums, so they just don't get out as much. All the things you can't do with a lead (or NiCd) battery are all the things where lithium batteries get the job done, usually without hurting anyone.

The average person owns only 1 lead-acid battery (in the car they own), zero NiCads, and well it would be almost impossible to count but maybe 100 lithium batteries. So the odds of them having trouble with one of their lithiums is bigger by a factor of 100 just based on the number of units in their house.

I wasn't expecting a rant this evening but here I am.
This thread is reading more like a pile-on attack than an analysis of technology.
Must've gotten under my skin.

Thank you to those who posted research reports - I read those and they are useful information.

 

[TugboatEng]

Sometimes it sounds like everyone is discovering all the problems and headaches that come with batteries, they're just named differently today.

I must disagree. While a lead acid battery can provide the energy to heat a high resistance fault to the point of fire, the battery itself is extremely unlikely to catch in fire itself compared to other technologies. I will also add that the mag-amp chargers that work so well with FLA batteries are highly reliable and less likely to contribute to problems.

 

[Sparweb]

What's this a picture of?

What happened to this?

Again?

 

[FacEngrPE]

NASA Spotlight on Lessons Learned: Battery Explosion

A lead acid battery used to start an emergency generator burst for no apparent reason and spread sulfuric acid near the generator. On May 17, 2010, the shell on the Generator No. 1 start-up battery broke and left acid and fragmentation in the area around the diesel generator.

Lead Acid batteries in emergency generator service with automatic float chargers fail often enough that we put them in heavy duty battery boxes. This is not really noticeable until you have a large fleet of portable generators.
I have seen one of these battery fires, they can get ugly if they catch sound proofing material on fire.

 

[IRstuff]

Lead-acid batteries produce hydrogen gas, and if not properly ventilated, can result in fires or explosions.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

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[resqcapt19]

An ad from one e-bike manufacture says that less than 15% of the e-bikes sold in the US comply with the applicable safety standards.

 

[waross]

A lead acid battery used to start an emergency generator burst for no apparent reason

I disagree with NASA's recommendations.
My solution;
Don't connect a float charger to a standby generator.
I have installed a lot of standby generators and seen a few exploded batteries.
Consider:
With no float charger, eventually the battery will fail and the generator won't start.
With a float charger, eventually the battery will fail and the battery will explode and the generator won't start.
After a number of battery explosions I disabled the float charger whenever I installed a generator.
I have never had a battery explosion in a set with no float charger.
Monthly test running is adequate to keep the battery charged.
As the battery nears the end of useful life, it will take longer to start the engine.
Been there too many times, and more times then NASA.
ps: Sparweb's pictures could have been from one of my gen sets.
--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[TugboatEng]

If it's important that your generator start I would suggest replacing lead acid batteries everything 2 years. They will nearly never have issues within that timeframe even on a float charger.

We use float chargers on our batteries as backup for when the alternators fail and those do fail frequently.

 

[waross]

Have you tried brushless alternators, Tug.
They are constructed so that the field coil is stationary.
Most marine failures I have seen were the result of stuck brushes.
That is not counting the unintentional cultural burnouts.
Before alternators were implemented, generators were problematic.
It was common to add rheostat control to generator fields so as to be able to adjust charging levels while at sea.
When generators were supplanted by alternators, the Rheostat controls were still field fitted.
If the Captain increased the engine speed a couple of hundred RPM, the engineer must cut back the rheostat setting to avoid over current burning out the alternator.
In a small fishing community, a young man made a comfortable living rewinding marine alternators, ... and building and installing rheostat controls.
When culture meets technology, technology is often the loser.

If it's important that your generator start I would suggest replacing lead acid batteries everything 2 years.

Most of the sets that I worked on were residential or small businesses.
Typically with little or no maintenance.
Often local maintenance was worse than no maintenance.
Replacing before failure was not culturally supported and failure was an option.
Not contradicting your advice, Tug.
Trying to explain local custom.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[Sparweb]

The aviation solution to batteries - all batteries - is to service them regularly.
Lead acid batteries need servicing somewhat less than NiCad batteries. This used to be the "simple tradeoff" between the "only two" types to choose from. Lead was "heavier but less maintenance" while NiCad was "lighter but more maintenance". Now Lithium has showed up and it's "much lighter with much less maintenance". So it's the winner as far as that goes, but after a few fires and meltdowns, the trust is gone. We forget that many people have been injured servicing nicads, and there have been emergencies due to failures of lead and nicad batteries. But that was so long ago...

Average folks with e-bikes and scooters aren't going to inspect or test the batteries inside them. They aren't always going to use a proper charger and some people will jury-rig things to get a bit more distance before the controller shuts it down. It doesn't matter what battery your e-bike or scooter has, any lead or NiCad battery would break down under this neglect, just like the lithiums do.

 

[TugboatEng]

Our main engines use brushless alternators and they are certainly more reliable. Our axillary engines had open crankcase vents and their alternators were very efficient at centrifuging oil mist. This led to stuck brushes. I put closed crankcase ventilation on the engines and reliability improved significantly. I recently replaced all generator sets in the fleet with smaller units. The alternator manufacturer changed from Denso to Mahle. The Mahle units are not good and I am experiencing failure at 1 year (2500 hours).

 

[ctopher]

I'm a cyclist. I find most e-bikes annoying because the riders don't know any rules, and don't care. They whip thru pedestrians, traffic, and cut off other cyclists.
I have seen them cause accidents and keep going. I think they should have the speed limits cut so they can't go as fast.

Chris, CSWP
SolidWorks
ctophers home

 

[hokie66]

Speed limits? Do you think they care? Or maybe you mean that e-bikes need speed limiters.

 

[ctopher]

Yes, e-bikes need speed limiters is what I meant

Chris, CSWP
SolidWorks
ctophers home

 

[waross]

Their speed is regulated in some jurisdictions.
If the max speed is set above the legal limit, they no longer qualify as E-bikes.
eg: Not road legal.
But who would know?
If one company consistently sets their limits too high their competitors will blow the whistle.


--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[BrianPetersen]

They're regulated to 30 km/h here. On some of them, apparently it is a trivial exercise to remove the speed limiter. Removing the legally-required pedals is another common one. A lot of the scooter-style models have pedals so that someone can put a check-mark on the checklist, but they're useless.

Cop with radar gun spots one doing more than 30 km/h is how they know it has been defeated. Or spots one without pedals. Big trouble: unlicensed motor vehicle, no insurance, frequently no driver's license.

 

[davefitz]

In most US states and canada, the e-bike is allowed to be treated as a biciycle if its output is less than 500 watts, over 500 watts it cannot be used on bike paths and the rider may need insurance and a motorcycle license. However, some afficianados will over-power the motor with a highder voltage battery , and there are some youtube videos from england that show the over-powered e-bike passing cars on the highway at more than 40 mph .

"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick

 

[ctopher]

e-bikes are not supposed to use bike paths, but they do anyway. I have seen them easily going 40mph, and without helmets. There is no control on bike paths unfortunately.

Chris, CSWP
SolidWorks
ctophers home

 

[IRstuff]

I'm a cyclist. I find most e-bikes annoying because the riders don't know any rules, and don't care. They whip thru pedestrians, traffic, and cut off other cyclists.

Same goes for what I call "bicycle Nazis," who feel that since they are able to blast by you at 30 mph, they rule the road and don't have to warn you that they're passing you, but it's worse, since they should know all the rules. They're going so fast that without the "On your left" warning, there could be a serious accident.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

https://www.youtube.com/watch?v=BKorP55Aqvg

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