DIY conversions can be dangerous!

[Mark911]

Electric Motorcycle Builds : The end of the electric rmz
Lucky nobody was hurt, but it shows just how vulnerable these Li-Ion based battery packs can be to getting damaged by an external failure or individual cell internal failure. There are so many failure modes which could have contributed to this situation it would be pure speculation to comment. As Alta owners we all depend on the reliability of our BMS system to prevent or at least mitigate the same thing from happening to our bikes. However, it's virtually impossible to reduce the chances to zero.

On a more happy note, I just completed my latest build; a 32hp KTM 85 based SuperMini . . . . . .

 

[snydes]

Was this @riverin ’s RMZ? That’s a shame, and certainly scary.

 

[Mark911]

Was this @riverin ’s RMZ? That’s a shame, and certainly scary.

Yes, I believe it was.

 

[Rashid510]

Yikes.

No propagation control = thermal runaway fun. This is why the many manufacturers of EVs take...time to figure this stuff out. Sure its cool to be first, but its pictures like in that link which lead to bad vibes of using/making/building EV products.

 

[C5tor]

Good reminder that these things can be dangerous. Almost any form of stored energy has the potential to release that energy catastrophically at any moment, whether it is electrical, chemical or mechanical. Anybody ever try to remove a compressed spring from a car? Scary.

There will be people in the anti-EV crowd out there that like to point to these isolated incidents to show how unsafe battery powered transportation is. I usually remind them that they are probably driving around in a vehicle with a giant Molotov cocktail of gasoline strapped behind their back seat, or even worse, situated between their legs on a motorcycle. People in flammable glass houses shouldn’t throw sparklers.

 

[snydes]

I had a neighbor who had parked his riding mower in the garage, walked in the house, next thing you know the whole garage is on fire. EV dangers are different, but essentially the same.

 

[privateer703]

I had a neighbor who had parked his riding mower in the garage, walked in the house, next thing you know the whole garage is on fire. EV dangers are different, but essentially the same.

That exact same thing happened to my friends father. Whole house went up.

 

[C5tor]

Just riffing on a theme here, but in 2019, there were 180,000 car fires in the USA alone! In the 1980’s the average was closer to 450,000 per year! We’ve come a long way in safety improvements, but the fact of the matter is that gasoline and other fuels like to combust. It is important that they do so to release the energy we need to propel us around, but it certainly has a dangerous downside.

I find it quite interesting that more gasoline cars have actually gone up in flames than there have been electric vehicles produced.

U.S. highway vehicle fires 1980-2019 | Statista

 

[riverin]

This is my bike. I rode the bike for 15km (1h30) during the day and I stopped many time to monitor everything. The highest temp I saw for the battery was 37 degree Celsius and looking at the spec from the cells the can go up to 60 degree. Physically the battery was rubber mounted so less vibration and no short with the case. My guess is that one cell from the pack went bad and even if I had each cells fused individually it did not protect the pack.

 

[VINSANITY]

I had a very scary battery fire in 2018. You can see the amount of fire damage in the pictures. The flames were 7-8 feet tall and lasted about 7-8 minutes. Luckily I was on a concrete road at the time and was able to drop the bike and let it burn. I was riding in the woods a few minutes earlier it is scary what could have happened.

The battery was purchased from a reputable company and ironically had been replaced by the company a few months earlier due to safety concerns.

 

[DonCox]

@riverin that is really tragic to see. All the work you put into that. There probably won't be much to "Post Mortem" after words. At least a second build will be easier. @VINSANITY had a similar event and rebuilt out of that. It seems like when these cells lite off they really put out some flames. My friend in Florida had a Lithium fire in his shop while he was working on it. Luckily he had a good respirator so he could fight the fire. Since then he works with a half barrel of water to throw any burning Lithium cells or packs into it to extinguish it. He said that the FAA says only water and or foam are required for lithium fires. But the fumes are really bad, so a respirator is also needed. I prepared my work area with those recommendations, for battery building. But spontaneous events are impossible to have the right things there. Vinsanity was luckily outside. Throw it into a pool or lake would be a good choice.
It sure makes you think more of the danger we are working with. But like @C5tor made a great point on ICE car fires.
I so wanted to see your bikes performance. and the QS 138 90H motor

 

[Mark911]

Yikes.

No propagation control = thermal runaway fun. This is why the many manufacturers of EVs take...time to figure this stuff out. Sure its cool to be first, but its pictures like in that link which lead to bad vibes of using/making/building EV products.

good point.... I’ve been building conversions with battery packs/BMS systems for almost two years now and haven’t sold one conversion to date. Why?....,until I get several hundred SUPERVISED charge/discharge cycles and many physical inspections in the books without failure I just don’t trust my design and manufacturing processes. Having a failure hours after use/charging adds another level of uncertainty and required product verification that I feel is now necessary.
on the other hand, I can assure everyone that these 18650 cells are quite robust. I’ve TRIED to get them to react but even direct shorting, 100% immersion in water, and many other likely anomalies and never a fire or even venting. Of course, I’m talking top of the line Sony and Panasonic cells designed for high discharge rates. I wouldn’t trust any cell that wasn’t from one of the big 5 manufactures regardless of cost or performance.
Quality cells properly supported and connected along with reasonable BMS parameters goes a long way towards making a safe pack. However, like turbos, it’s so easy to make more power by simply “turning up” the boost, Its very tempting to push the electrical envelope. Right up to the point where the ring lands crack, blow a head gasket or .......,,

 

[Fourth_Floor]

Such a bummer, that build looked nice. I've noticed since Alta has gone out of business and finding bikes is becoming more and more difficult I'm seeing more and more of these DIY builds. The market is clearly there if guys are so desperate for an electric bike they're willing to try building the thing themselves and I totally get it. Because of where I live, if I didn't have an Alta I wouldn't have gotten back into riding. The big dogs needs to get off their asses sooner rather than later and put out some electric motocross bikes. I have a feeling KTM is going to be the first to do it, question is when?

 

[privateer703]

The main manufacturers made an agreement to standardize batteries, you think they could've worked with BRP (paid them $$) to just repurpose the Alta IP and use what is clearly a solid battery. This is the part where I say something about not seeing any Alta batteries exp$#%$@...but I'm not saying it.

 

[Rix]

I had a very scary battery fire in 2018. You can see the amount of fire damage in the pictures. The flames were 7-8 feet tall and lasted about 7-8 minutes. Luckily I was on a concrete road at the time and was able to drop the bike and let it burn. I was riding in the woods a few minutes earlier it is scary what could have happened.

The battery was purchased from a reputable company and ironically had been replaced by the company a few months earlier due to safety concerns.

View attachment 7021

View attachment 7022

View attachment 7023

View attachment 7024

View attachment 7025

View attachment 7026

View attachment 7027

That really sucks, that frame was a David Pearce first ever dedicated ebike only frame. Phasor cycles is no more and you don't see many of these around anymore.

 

[Rix]

Electric Motorcycle Builds : The end of the electric rmz
Lucky nobody was hurt, but it shows just how vulnerable these Li-Ion based battery packs can be to getting damaged by an external failure or individual cell internal failure. There are so many failure modes which could have contributed to this situation it would be pure speculation to comment. As Alta owners we all depend on the reliability of our BMS system to prevent or at least mitigate the same thing from happening to our bikes. However, it's virtually impossible to reduce the chances to zero.

On a more happy note, I just completed my latest build; a 32hp KTM 85 based SuperMini . . . . . .View attachment 7028

The perfect bike!!! a 40HP mini!!! I like your priorities.

 

[VINSANITY]

That really sucks, that frame was a David Pearce first ever dedicated ebike only frame. Phasor cycles is no more and you don't see many of these around anymore.

I still have the Phasor frame. It is chromoly and appears to have survived to the point I think it can be used. One day considering rebuilding. Fortunately the company I purchased the battery and power system from did a warrantee replacement and this is what I ended up with today.

 

[Rix]

I still have the Phasor frame. It is chromoly and appears to have survived to the point I think it can be used. One day considering rebuilding. Fortunately the company I purchased the battery and power system from did a warrantee replacement and this is what I ended up with today.

View attachment 7033

Thats nice, really like the Motoped electric conversion platform. You running the QS205?

 

[Rix]

Electric Motorcycle Builds : The end of the electric rmz
Lucky nobody was hurt, but it shows just how vulnerable these Li-Ion based battery packs can be to getting damaged by an external failure or individual cell internal failure. There are so many failure modes which could have contributed to this situation it would be pure speculation to comment. As Alta owners we all depend on the reliability of our BMS system to prevent or at least mitigate the same thing from happening to our bikes. However, it's virtually impossible to reduce the chances to zero.

On a more happy note, I just completed my latest build; a 32hp KTM 85 based SuperMini . . . . . .View attachment 7028

I can't find the actual website. This is what I typed in the browser, I get nothing but online education referrals. www.MSCEngineering.org

 

[Mark911]

I can't find the actual website. This is what I typed in the browser, I get nothing but online education referrals. www.MSCEngineering.org

My business website isn't up right now if that's what you're referring to. It should have re-directed you to my Instagram page @maxvonauto.