Battery fires?

dodgeman

Well-Known Member
Region
USA
City
Macomb, Illinois
So I did a search on battery fires and found several threads. One thing I haven’t found is what is causing fires? Are the batteries catching fire? Do they get hot and catch nearby things on fire? If you have a brand name bike, say Trek with the Bosch motor is that safer?
 

rich c

Well-Known Member
Bosch battery packs are UL rated, so yes they are safer. Yes the batteries are catching fire. The cells explode and shoot off like bottle rockets. It's very difficult to put out the chemical fire and once it gets hot enough, everything catches fire.
 

Gordon71

Well-Known Member
So I did a search on battery fires and found several threads. One thing I haven’t found is what is causing fires? Are the batteries catching fire? Do they get hot and catch nearby things on fire? If you have a brand name bike, say Trek with the Bosch motor is that safer?
Why would a particular brand of motor make whatever battery that's powering it safer?
 

dodgeman

Well-Known Member
Region
USA
City
Macomb, Illinois
I don’t know if someone like Bosch makes the battery or specs the battery or if Trek does. I’m asking, I don’t know the answer.
 

Gordon71

Well-Known Member
I don’t know if someone like Bosch makes the battery or specs the battery or if Trek does. I’m asking, I don’t know the answer.
I really know nothing about Trek EBikes so I went over to their site. As far as I can tell the don't sell batteries at all or I couldn't find any for sale at their site which is weird. How can they sell EBikes and not sell replacement batteries?
 

Stefan Mikes

Well-Known Member
Region
Europe
City
Mazovia, Poland
I really know nothing about Trek EBikes so I went over to their site. As far as I can tell the don't sell batteries at all or I couldn't find any for sale at their site which is weird. How can they sell EBikes and not sell replacement batteries?
Spare batteries are available for Bosch E-Bikes (such as Trek), Specialized, and Giant for sure. In case of Trek, the battery is a Bosch E-Bike product, and as such, it does not need to be advertised on the Trek website.
For your information, I own as many as three Specialized U1-600 batteries, and as many as three Specialized SL Range Extenders. A friend of mine bought a Bosch spare battery for his Merida e-bike last Autumn.

I'm sure other big brands sell spare batteries, too.
 

Gordon71

Well-Known Member
Spare batteries are available for Bosch E-Bikes (such as Trek), Specialized, and Giant for sure. In case of Trek, the battery is a Bosch E-Bike product, and as such, it does not need to be advertised on the Trek website.
For your information, I own as many as three Specialized U1-600 batteries, and as many as three Specialized SL Range Extenders. A friend of mine bought a Bosch spare battery for his Merida e-bike last Autumn.

I'm sure other big brands sell spare batteries, too.
OK I was just surprised that a Ebike dealer wouldn't have replacement batteries as part of their inventory.
 

Stefan Mikes

Well-Known Member
Region
Europe
City
Mazovia, Poland
OK I was just surprised that a Ebike dealer wouldn't have replacement batteries as part of their inventory.
There's a general lack of spare batteries in the market because of known reasons... Not that they would not be offered if available. Besides, I believe it is rather difficult to order a spare battery from a big brand online. (I might be wrong but I cannot see, say, spare Specialized batteries available on the European websites but I could have got them ordered by the LBS).
 

retiredNH

Well-Known Member
Region
USA
I really know nothing about Trek EBikes so I went over to their site. As far as I can tell the don't sell batteries at all or I couldn't find any for sale at their site which is weird. How can they sell EBikes and not sell replacement batteries?
It's because they're Bosch made and branded batteries. In Trek's case, and probably others who use the Bosch systems, you get the batteries from Bosch.
In answer to whether battery brand matters, it's like anything else we buy, except that with batteries, the stakes are higher - you can buy at a range of price points, with different quality (in some cases). Some things are better made, but at a price.
Manufacturers develop specifications for products they make and sell, which can influence performance, safety and price. Name brand ebike component manufacturers like Bosch and Specialized are known for reliable, sturdy components, at a high price point. No-name manufacturers typically focus on price, at the sacrifice of everything else - longevity, durability, safety etc.
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
So I did a search on battery fires and found several threads. One thing I haven’t found is what is causing fires? Are the batteries catching fire? Do they get hot and catch nearby things on fire? If you have a brand name bike, say Trek with the Bosch motor is that safer?
1. Charging, especially when using a junk or incorrect charger or charging when the pack is hot. My bet is this is what's causing the majority. For instance- most chargers are set up to shut off at a particular voltage. If there is a dead or bad cell, maybe multiple bad cells, (or maybe frozen, ?) within the pack, the voltage will never get up to the point where the charger shuts itself off. This can result in a battery pack that just keeps getting hotter and hotter with predictable results.

2. A dead short within the battery pack can cause a runaway (over heating) issue as well.

3. Poor construction can allow cells to rub together, against wiring, against anything, and eventually the battery cell case may wear through allowing it to vent - causing a fire. Older batteries that have been allowed to sort of rattle around within a container or case are especially well known for this.

I'm sure there are other reasons, especially when talking home made, but that should give you an idea....