Might have damaged my battery pack! ;(

[TeslaBike]

So this just happened....

The battery shorted on the aluminium box and now one of the 18650 has a melted hole on the side and it exposed the lithium! I can see some oxidation on the top layer happenig right now. It is not overheating.
I also smelled the lithium, was like acetone.
I had the hot glue gun running and my first instint was to close it with a blob of hot glue to stop oxidation...... It probably wasn´t the best idea but its done now..... Is it safe as it is? What should I do??!

 

[Ravi Kempaiah]

So this just happened....

The battery shorted on the aluminium box and now one of the 18650 has a melted hole on the side and it exposed the lithium! I can see some oxidation on the top layer happenig right now. It is not overheating.
I also smelled the lithium, was like acetone.
I had the hot glue gun running and my first instint was to close it with a blob of hot glue to stop oxidation...... It probably wasn´t the best idea but its done now..... Is it safe as it is? What should I do??!

This is a tragedy waiting to happen!
Be extremely cautious. Chemical reactions happen on the inside and even though everything looks calm, it can catch fire at any time. That seems like a deep puncture.
If the cell was at low voltage before this happened, may be you are lucky! How the hell did it short on the side? was it punctured or hit from the side of the Alu box?

If you are skilled at handling things like this, you can isolate the defective cell from the rest of the pack. Once that is isolated, the chances of danger are much less.
Be super cautious welding a new cell into that pack as it might introduce extra resistance.

Call these folks and see what they suggest: https://rechargeablepowerenergy.com/

 

[TeslaBike]

This is a tragedy waiting to happen!
Be extremely cautious. Chemical reactions happen on the inside and even though everything looks calm, it can catch fire at any time. That seems like a deep puncture.
If the cell was at low voltage before this happened, may be you are lucky! How the hell did it short on the side? was it punctured or hit from the side of the Alu box?

If you are skilled at handling things like this, you can isolate the defective cell from the rest of the pack. Once that is isolated, the chances of danger are much less.
Be super cautious welding a new cell into that pack as it might introduce extra resistance.

Call these folks and see what they suggest: https://rechargeablepowerenergy.com/

Let me describe what I see...... The metal shell melted, and it exposed the outer layer of lithium.... It did NOT puncture through layers, Just exposed the top layer! That being said, do you think it can still over heat or catch fire??

I was reckless.... I wanned to see how the pack would sit inside the box.... nothing was insolated.... and that 18650 batt must have had some of the plastic peled off from previous hot glue....

The cells are brand new and have 3.7V each!

EDIT: Taking that cell out is nearly impossible.... I would have leave it there, isolated, glue another cell onto the side and run wires from the cell to the damaged cell row..... Could it be done like this?! I think its the only way of saving this pack..... ;(

 

[Ravi Kempaiah]

The metal shell melted, and it exposed the outer layer of lithium

When the outer metallic shell melts, it exposes what you call "active material" to the atmosphere. If the two ends, anode and cathode come in contact, the cell will release huge amounts of energy in seconds leading to fire.
You don't want to burn your house down. This individual cell is $4 but your house may be millions of $$.
If you can't isolate the defective cell, you will have to extremely cautious with fixing this pack. I can not emphasize this enough. Don't just leave it there.
I applaud your skills to build a battery but things like this are dangerous even to the most experienced builders. I have not built a lot of packs myself but I work with these materials everyday.

If I were you, I would think of safe ways to get rid of that defective cell ASAP. Good luck!

PS: your life/property is more valuable than this tiny pack. Safety must be your first consideration.

 

[TeslaBike]

When the outer metallic shell melts, it exposes what you call "active material" to the atmosphere. If the two ends, anode and cathode come in contact, the cell will release huge amounts of energy in seconds leading to fire.
You don't want to burn your house down. This individual cell is $4 but your house may be millions of $$.
If you can't isolate the defective cell, you will have to extremely cautious with fixing this pack. I can not emphasize this enough. Don't just leave it there.
I am applaud your skills to build a battery but things like this are dangerous even to the most experienced builders. I have not built a lot of packs myself but I work with these materials everyday.

If I were you, I would think of safe ways to get rid of that defective cell ASAP. Good luck!

PS: your life/property is more valuable than this tiny pack. Safety must be your first consideration.

Thanks for the heads up friend....I will follow the advice!
I am stress out because I dont have the tools with me! so I was making sure, from your explanation, that this cell as it sits, isn´t in iminet danger of exploding/catching fire!

This is my first pack so I dont have experience dealing with these cells. Could I wire the substitute cell as I mention above?

 

[Volt_Ampere]

You need to find a way to remove and replace that damaged cell! I am sure it can be done if you work at it.

 

[Off road all day]

GET IT AWAY! a single cell rupture caused a series of lithium's to explode and brought down a UPS 747 in Dubai. Since then lithium's are transported in special containers.
Best advice i can give is take it outside NOW.
Don't bother trying to salvage the pack just pay the extra $ for an LG, Panasonic, etc brand name. My battery cost 5 times the price of my frankenbike.
I call it that because it has parts from 2 bikes and a few aftermarket parts, plus some metal rods from lawn ornaments.

 

[TeslaBike]

You need to find a way to remove and replace that damaged cell! I am sure it can be done if you work at it.

Don't know if I can do it Volt.... As I was gluing the the first 3 cells of the 6P row, I quickly realised it wouldn't fit in the box, so I began cutting and pulling the hot glue with a scalp and pliers and used a flat head screwdriver driver to try pushing them apart. They went traight to the strash can after they came out. Sometimes you can unstick the hot glue but if you glue it right the plastic cover as to breakes as well.

 

[erider_61]

I have used a heat gun to soften glue to unstick things before. Like others have said, I would remove this battery pack asap from my house/garage before a catastrophic failure occurs. Maybe in future you could use a flexible silicon caulking to stick cells together. Would be much easier to service in the future.

 

[TeslaBike]

GET IT AWAY! a single cell rupture caused a series of lithium's to explode and brought down a UPS 747 in Dubai. Since then lithium's are transported in special containers.
Best advice i can give is take it outside NOW.
Don't bother trying to salvage the pack just pay the extra $ for an LG, Panasonic, etc brand name. My battery cost 5 times the price of my frankenbike.
I call it that because it has parts from 2 bikes and a few aftermarket parts, plus some metal rods from lawn ornaments.

I have used a heat gun to soften glue to unstick things before. Like others have said, I would remove this battery pack asap from my house/garage before a catastrophic failure occurs. Maybe in future you could use a flexible silicon caulking to stick cells together. Would be much easier to service in the future.

Off road, I already placed the pack in a box and will sleep under the stars on my garden. What a wierd ending!

erider, I will give it a try! The ideia of heating up that battery makes me nervous tho....

 

[Volt_Ampere]

Cut on the side toward the damaged battery so that you don't damage the neighbors. Try using a hot knife which should cut through the glue more easily.

 

[John from Connecticut]

So this just happened....

The battery shorted on the aluminium box and now one of the 18650 has a melted hole on the side and it exposed the lithium! I can see some oxidation on the top layer happenig right now. It is not overheating.
I also smelled the lithium, was like acetone.
I had the hot glue gun running and my first instint was to close it with a blob of hot glue to stop oxidation...... It probably wasn´t the best idea but its done now..... Is it safe as it is? What should I do??!

I agree with Ravi..."This is a tragedy waiting to happen!" I have a strong technical professional background in electronics and I would not 'touch' this
Science Project with '20 foot pole. Your battery has the potential to turn your downtube into a pool of molten metal and and or create a chemical fire
( while you're riding ? ) that you cannot extinquish. Chemical burns on skin are no fun. This is not amateur night in my opinion !

 

[harryS]

The burnt cell is not in a bad spot as far as removal. I believe that it and its neighbor could be removed if the plastic cover around each cell is slit. The glue only holds the cover as the OP said. You have to be careful, as I don't know if the cell can still ignite. Assume it can.

Or get a solder iron tip and melt the glue (like a hot knife) . The risk is that the 2nd and third cell in the outer row have their cases at different voltages. You have to cut the busses, so the cells being worked on will float.

 

[SirJonathan]

I would write that thing off so fast my head would spin! I'm nervous just with my stock 52V battery with no issues. I keep it in the garage which has a fire door to our house and I have nothing around it that could catch fire. I only charge it outside on the patio away from the house and when I'm able to watch it.

Seeing that would make me take that down to our hazardous waste disposal drop-off and consider it a lesson - and a cheap one at that. I would never rest easy with that in my house, on my bike, when charging, when riding - or anywhere but in a metal trash container with the lid on.

I guess I'm risk averse.

 

[erider_61]

 

[ebikemom]

Where to take something like that? The fire department? What should someone do in this situation? "Put it outside" could also be a disaster and cause a wildfire, depending on the region. Thoughts? If one doesn't have a fire pit handy in the backyard, what to do? Maybe put it in the BBQ grill?

 

[TeslaBike]

It took me a while but I manage to pull the cell out of the pack and replace it, its all good now!

I lost a couple hours of sleep but Im relived that nothing happened and i´ll be able to use the pack. But I now see how dangerous these things can be and cutting corners is a bad idea. I´ll never do that again thats for sure.

I didn´t tell you before but the short circuit was so violent that it made a huge spark and caught my jersey on fire and quickly climbed up to my neck! I fell of my chair, it was unreal, scared the s*it out me!!!

I apreciate all the help and advice guys!

 

[erider_61]

Glad you are ok. May I suggest that you video all future battery builds. You just might go viral on You Tube...lol

 

[J.R.]

It took me a while but I manage to pull the cell out of the pack and replace it, its all good now!

I lost a couple hours of sleep but Im relived that nothing happened and i´ll be able to use the pack. But I now see how dangerous these things can be and cutting corners is a bad idea. I´ll never do that again thats for sure.

I didn´t tell you before but the short circuit was so violent that it made a huge spark and caught my jersey on fire and quickly climbed up to my neck! I fell of my chair, it was unreal, scared the s*it out me!!!

I apreciate all the help and advice guys!

I hope you live in a fully detached, individual dwelling unit. I'm not piling on. Consider other family members, pets and neighbors in this experiment. Not to mention the firemen and women that would deal with the fire. I'd also wonder if homeowners insurance would pay out for damage with such volatile experiments. I'm not suggesting they won't, I just don't know.

Some useful safety information from Battery University:

https://batteryuniversity.com/learn/article/safety_concerns_with_li_ion

I find building a pack an intriguing proposition. It's always come down to dollars and sense, not cents. The old adage of being penny wise and pound foolish. You have provided a teaching moment and I thank you for being open and honest.

Be safe and good luck.

 

[TeslaBike]

Glad you are ok. May I suggest that you video all future battery builds. You just might go viral on You Tube...lol

Ahahah kinda like "ElectroBoom" the indian guy who shocks in self on purpose

I hope you live in a fully detached, individual dwelling unit. I'm not piling on. Consider other family members, pets and neighbors in this experiment. Not to mention the firemen and women that would deal with the fire. I'd also wonder if homeowners insurance would pay out for damage with such volatile experiments. I'm not suggesting they won't, I just don't know.

Some useful safety information from Battery University:

https://batteryuniversity.com/learn/article/safety_concerns_with_li_ion

I find building a pack an intriguing proposition. It's always come down to dollars and sense, not cents. The old adage of being penny wise and pound foolish. You have provided a teaching moment and I thank you for being open and honest.

Be safe and good luck.

I get your concerns... If I lived in a flat or were surrounded by people and flamable materials I wouldnt be doing this stuff.
In this case theres not much that can go wrong other than hurting myself. I´m lucky that my patio and garage are spacious and the only wood is my working bench. It would be nearly impossible to burn my house down or the neighbors if the heat source is outside the house. It´s all stone and tile.
I also have a homemade hidrogen and oxigen generator in the garage and I feel pretty safe there

Regarding the pack building, I agree, its quite tricky and dangerous especialy the way I did it. But like you said, if you spend the extra cash on the right tools and materials like spot welder, shrink tubing etc and follow good advice it can be done quite easily in my perspective.