I think I understand New York's ebike fire problem a little better now.

rob feature

Well-Known Member
Region
USA
City
Greenwood Village, Colorado
It had been a while since i'd been to the city. The last time I was there, I don't recall seeing any e-bikes. Probably because they didn't exist. But on a trip there a few days ago, I had a short list of things that I wanted to do - and one of those was to check out the e-bike scene...which I assumed was robust and vibrant. I was not disappointed.

However, it didn't take long for something to stand out. Most of these bikes looked the same. And when I say most, I mean a solid 99% or better. A large number of these seemed to be used for delivery or messenging of some sorts. A little Googling suggest these may be from the Arrow brand, but admittedly I was too interested in their modifications than what was scribbled on the frames.

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These were mostly hardtails with long chainstays as the batteries are tucked between the seat tube and the rear wheel. Seems like most had some front suspension, fenders, racks and hub-drive motors with throttles. Most were covered in some sort of tape. The battery packs look like they could be swapped among the bikes - all the same. They also have some sort of funky box under and around the bottom bracket - a BMS maybe?

1.jpg


They were as ubiquitous as the NYC yellow taxi. Their riders did not seem concerned with rules - riding at relatively breakneck speeds, disregarding street directions, sidewalks, pedestrians, and anything else that might be in the way of them getting where they were going as efficiently as possible...courtesy be damned.

That also made me start thinking this would be the crowd that would cut corners when it comes to safety. Specifically battery safety. There have to be shops/clubs/guys in the city that specialize in these things and store piles of these batteries - probably modifying and experimenting. Considering the builds of the bikes, which appear to be somewhat disposable and customizable, one can only assume that the batteries are sporting the same philosophy.

It would make sense right - as profits all too often trump safety. And who really spends more than they have to? But to me these seem like smoking guns - the answer to why ebike fires are such a big problem in New York City. Maybe I'm way off here, but maybe not. Again, it seemed immediately obvious that this had to be a big part of it.

To take that idea a little further, I think I saw 2 'proper' ebikes aside from these curiosities and the Citi bikes...a brand new Trek in Central Park and a Riese & Mueller in front of a fancy pants restaurant where a friend had invited me for lunch. They were a tiny minority of what I saw. Outside of Central Park I mostly saw only Citi bikes that were not ebikes.

I did spend some time on Citi bikes - both electric and analog and will talk about those in a different thread, but the proliferation of these 'Arrow' bikes and their dominance on the streets was more than noteworthy.

I got a little off topic there though - back to the batteries. While there seem to be tens of thousands of these all over the place, one has to assume that they're built and treated maybe as well as the bikes themselves - which is to say cheap, highly modified, poorly-maintained and skectchy. Many obviously live outside - tethered by huge chains to lightposts, streetsigns, trees, other bikes - pretty much anything that could serve as an anchor. Their riders did not seem to be a particularly technical bunch - judging by their appearance, their bikes' appearance, and their chosen profession. All that together made me think they may be inclined to make ill-informed decisions regarding batteries, mods to batteries, and general battery safety. I did not find cars and trucks to be intimidating riding around NYC on a bike, but other bikes and scooters - those were what I needed to watch out for. If something was going to take me out, it was going to be one of these guys.

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To those a little more in the know, am I barking up the right tree here? Is there something to this idea? Or am I unfairly picking at the masses simply trying to scratch out a living in America's most populated city?
 
There is a podcast from someone with some expertise with batteries. He said that with temperature changes a battery "breathes". What he means is air is pushed out of the battery case when the temperature rises and is sucked in when the ambient temperature falls. So the battery will tend to condense water inside the case and cause corrosion of all those connecting strips. He also said NYC is wealthy enough to salt the roads and sidewalks for all winter. That salt will also enter the battery as it "breathes". The NYC delivery bikes tend to live outside and are ridden all year, so delivery bikes there will tend to have a high rate of catastrophic battery failures.
 
He said that with temperature changes a battery "breathes". What he means is air is pushed out of the battery case when the temperature rises and is sucked in when the ambient temperature falls.

The way I figure it is if a battery is quite warm then it gets wet from rain or splashes from puddles, the battery cools very quickly and can easily suck water into the battery, even salty water.

I doubt that it's just condensation from damp air that gets into a battery.
 
My son was looking for his stolen bike, and he wandered into one of these E bike chop shops. They take stolen bikes often and build them for delivery drivers who are undocumented and cannot get jobs doing anything but delivery. He said it was a very scary looking place and he exited quite quickly.
 
Let's not forget that plenty of electrical grid within NYC metro can be over 100 years old and still operating to supply modern day electrical demands;
like super-sized washer/dryer, microwaves, dishwashers, heater, A/C units, electrical cookers, etc.

I've been commuting on my (folding) bicycle & e-bike in NYC traffic since 2013 (e-bike since 2017).
There is no doubt that e-bikes and bicycles have changed the landscape & traffic flow within NYC metro.
The Arrow e-bikes are actually very capable machines and well-built for their purposes.

Whether these fires started due to e-bike batteries (lithium or other type) can be difficult to determine.
Does battery fire leave bike tires on the bike rims un-melted and some still hold air?
Metal (& plastic) casing for some batteries still look intact?
image_1__ef334a0894a1f8636d787bf6dfa2f8246cc6841c.png
 
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I dunno, but there are 3 Arrow style batteries at the bottom of that photo
 
I really don’t think it a mystery.
Not the best batteries are used in tough conditions. Then left on chargers so that they are full when needed.
Lastly the end users are not educated (in battery safety) and work long hard days.
As in the days of the sweatshop, the bottom of the ladder always pay dearly and with collateral.
 
I dunno, but there are 3 Arrow style batteries at the bottom of that photo
Does any of those 3 look like it had been an explosion or ignited to start a massive fire?
Would the plastic part of the battery still be intact if the battery did explode?
I'd imagine the fire would have melted the plastic parts & tires from all the e-bikes in a lithium fire.
 
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Does any of those 3 look like it had been an explosion or ignited to start a massive fire?
Would the plastic part of the battery still be intact if the battery did explode?
I'd imagine the fire would have melted the plastic parts & tires from all the e-bikes in a lithium fire.
Yeah, probably. But that's probably not all of them either. That's a pretty big pile. It's also hard to say if the ones visible in the photo are in good condition.

I'm not saying Arrow batteries caused this, but they were in the neighborhood at the time.
 
It had been a while since i'd been to the city. The last time I was there, I don't recall seeing any e-bikes. Probably because they didn't exist. But on a trip there a few days ago, I had a short list of things that I wanted to do - and one of those was to check out the e-bike scene...which I assumed was robust and vibrant. I was not disappointed.

However, it didn't take long for something to stand out. Most of these bikes looked the same. And when I say most, I mean a solid 99% or better. A large number of these seemed to be used for delivery or messenging of some sorts. A little Googling suggest these may be from the Arrow brand, but admittedly I was too interested in their modifications than what was scribbled on the frames.

View attachment 157601

These were mostly hardtails with long chainstays as the batteries are tucked between the seat tube and the rear wheel. Seems like most had some front suspension, fenders, racks and hub-drive motors with throttles. Most were covered in some sort of tape. The battery packs look like they could be swapped among the bikes - all the same. They also have some sort of funky box under and around the bottom bracket - a BMS maybe?

View attachment 157599

They were as ubiquitous as the NYC yellow taxi. Their riders did not seem concerned with rules - riding at relatively breakneck speeds, disregarding street directions, sidewalks, pedestrians, and anything else that might be in the way of them getting where they were going as efficiently as possible...courtesy be damned.

That also made me start thinking this would be the crowd that would cut corners when it comes to safety. Specifically battery safety. There have to be shops/clubs/guys in the city that specialize in these things and store piles of these batteries - probably modifying and experimenting. Considering the builds of the bikes, which appear to be somewhat disposable and customizable, one can only assume that the batteries are sporting the same philosophy.

It would make sense right - as profits all too often trump safety. And who really spends more than they have to? But to me these seem like smoking guns - the answer to why ebike fires are such a big problem in New York City. Maybe I'm way off here, but maybe not. Again, it seemed immediately obvious that this had to be a big part of it.

To take that idea a little further, I think I saw 2 'proper' ebikes aside from these curiosities and the Citi bikes...a brand new Trek in Central Park and a Riese & Mueller in front of a fancy pants restaurant where a friend had invited me for lunch. They were a tiny minority of what I saw. Outside of Central Park I mostly saw only Citi bikes that were not ebikes.

I did spend some time on Citi bikes - both electric and analog and will talk about those in a different thread, but the proliferation of these 'Arrow' bikes and their dominance on the streets was more than noteworthy.

I got a little off topic there though - back to the batteries. While there seem to be tens of thousands of these all over the place, one has to assume that they're built and treated maybe as well as the bikes themselves - which is to say cheap, highly modified, poorly-maintained and skectchy. Many obviously live outside - tethered by huge chains to lightposts, streetsigns, trees, other bikes - pretty much anything that could serve as an anchor. Their riders did not seem to be a particularly technical bunch - judging by their appearance, their bikes' appearance, and their chosen profession. All that together made me think they may be inclined to make ill-informed decisions regarding batteries, mods to batteries, and general battery safety. I did not find cars and trucks to be intimidating riding around NYC on a bike, but other bikes and scooters - those were what I needed to watch out for. If something was going to take me out, it was going to be one of these guys.

View attachment 157600

To those a little more in the know, am I barking up the right tree here? Is there something to this idea? Or am I unfairly picking at the masses simply trying to scratch out a living in America's most populated city?
"...profits too often trump safety." Sounds like Boeing, who also had problems with lithium batteries. They tried them in their new Dreamliner, but encountered overheating and had to give them up. I don't know what their final solution was. That's not to say the batteries contributed to the 737s (?) falling out of the sky; that was due to a different screw-up.
 
Yeah, probably. But that's probably not all of them either. That's a pretty big pile. It's also hard to say if the ones visible in the photo are in good condition.

I'm not saying Arrow batteries caused this, but they were in the neighborhood at the time.
The battery style is called'silverfish" and they are mostly interchangeable.
 
To those a little more in the know, am I barking up the right tree here? Is there something to this idea? Or am I unfairly picking at the masses simply trying to scratch out a living in America's most populated city?
In NYC you have an almost unique-to-the-USA situation where you have a massive underclass of delivery workers - very low wage earners - who have turned to ebikes to make their living. Thats a day-in-day-out exercise and is very far from the occasional exercise ride engaged in my recreational type riders most commonly found in the US.

So component service due to the high duty cycle is required. Also, stuff just plain wears out. And these worker-riders don't have much money to start with. So there is an entire class of more or less underground repair shops who will, for example, service an expensive ebike battery (cheap by affluent recreational rider standards) or replace it. How do they replace it? often by manually pulling cells from a bad pack and using a bunch of them to make up a new one, stuffed into a used case from another bad pack. The prices for this kind of work are low, as is the quality compared to - again I'll use the word - affluent recreational rider products. What would be considered a minimum level of safety has to go by the wayside as needs must given the economic circumstances of all involved.

I haven't even touched on the subject of charging which is its own little horror show.

The kinds of catastrophic failures seemingly routine in NYC and largely unheard of in the rest of the country are due to a slew of factors that have created a unique environment. You can make all the UL certification requirements you want and it will just move the result underground. The true solution to the problem has nothing to do with ebikes.
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The Boeing 787 was revolutionary in many respects, one of which was the heavy use of electrical actuators for systems like flaps instead of hydraulics. But this meant they had to store much more electricity on board. They turned to lithium cells. Within a few years of deployment, several of those new battery packs began to fail. The fault was found to be overheated cells, which ignited other cells, much like the NYC ebike fires. Boeing still uses lithium cells but they greatly tightened up the QC and redesigned the battery box to totally contain a fire inside and also to vent fumes overboard. I understand they also increased cell spacing and insulation to better isolate cell failures.

It is obvious by now that lithium cells require rigorous quality control during manufacture. Cells from the likes of LG, Panasonic, and Sony are of excellent quality. Cells made by no-name companies in China can be absolute junk. Use junk cells without proper internal thermal and voltage protections and you have a potential firebomb.
 
The Boeing 787 was revolutionary in many respects, one of which was the heavy use of electrical actuators for systems like flaps instead of hydraulics. But this meant they had to store much more electricity on board. They turned to lithium cells. Within a few years of deployment, several of those new battery packs began to fail. The fault was found to be overheated cells, which ignited other cells, much like the NYC ebike fires. Boeing still uses lithium cells but they greatly tightened up the QC and redesigned the battery box to totally contain a fire inside and also to vent fumes overboard. I understand they also increased cell spacing and insulation to better isolate cell failures.

It is obvious by now that lithium cells require rigorous quality control during manufacture. Cells from the likes of LG, Panasonic, and Sony are of excellent quality. Cells made by no-name companies in China can be absolute junk. Use junk cells without proper internal thermal and voltage protections and you have a potential firebomb.
The "Dreamliner" was a new piece of aviation innovation and it brought to light the possible problems with lithium cells during its "teething" phase, Hope she will go on the books as a plane to remeber like the "Queen of the skies" and the good thing about all this, the tech will filter down to us ebike enthusiasts as well.
 
The way I figure it is if a battery is quite warm then it gets wet from rain or splashes from puddles, the battery cools very quickly and can easily suck water into the battery, even salty water.

I doubt that it's just condensation from damp air that gets into a battery.
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The "Dreamliner" was a new piece of aviation innovation and it brought to light the possible problems with lithium cells during its "teething" phase, Hope she will go on the books as a plane to remeber like the "Queen of the skies" and the good thing about all this, the tech will filter down to us ebike enthusiasts as well.
Or, "the flying Dutchman of the skies." The Netflix special on Boeing's problems is very revealing. For the first half of its history, the company was known for serious quality control and safety; then they merged with McDonnel Douglas, and maximizing profits became the new operating paradigm. Apparently many of the old guard engineers and mechanics were very disgruntled. I don't see much flying in my future, but I hope not to be in a Boeing airplane when I do.
 
I saw that documentary after hearing the author interviewed at length on NPR. McDonnel Douglas should be shot for what it did to Boeing's corporate culture and engineering standards. The world needs more old Boeings — especially the ebike industry.

Wonder how many Li-ion batteries a modern jetliner uses and how they're managed?
 
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