Lead Sulfate Mixed with Metallic Lead and Other Metals, Any Reactions?

https://www.scientificamerican.com/article/battery-fires-pose-new-risks-to-firefighters/

https://prod-ng.sandia.gov/techlib-noauth/access-control.cgi/2018/182505r.pdf

It's pretty hard to burn a battery mostly they just explode...

..."About 60% of the weight of an automotive-type lead–acid battery rated around 60 A·h is lead or internal parts made of lead; the balance is electrolyte, separators, and the case. For example, there are approximately 8.7 kg (19 lb) of lead in a typical 14.5-kg (32 lb) battery."...

https://en.wikipedia.org/wiki/Lead%E2%80%93acid_battery

I also think they most of the time would explode, but if you had a hot fire of 700-1000 C lasting about 20 min the room, some lead might leak out and get molten?, what do you think about the scenario in my post?.

https://energystorageforum.com/news/battery-fire-kahuku-wind-energy-storage-farm

It would appear that lead/acid batteries are not used in all cases...

http://www.hawaiifreepress.com/ArticlesMain/tabid/56/ID/11177/Lloyds-of-London-Lawsuit-Reveals-Story-Behind-Kahuku-Windfarm-Fires.aspx

Charged lead-acid batteries have one plate with PbO₂ and the other one Pb. Discharged batteries have both plates PbSO₄. So neither one is pure lead. The electrolyte is sulfuric acid, more concentrated when the battery is charged.

The chance of fire would be if a charged battery is shorted. Lead-acid batteries have very low internal resistance and can produce large currents. Lead metal itself is fairly inert, even when molten, but could cause a fire if it came into contact with combustibles. The electrolyte is very corrosive and reactive.

https://en.wikipedia.org/wiki/Lead%E2%80%93acid_battery

Lead-acid battery are routinely recycled. Here is some information that may prove useful.

https://www.cjdecycling.com/lead-acid-battery-recycling-need-know/

Information on all kinds of battery can be found here.

https://batteryuniversity.com/

"Charged lead-acid batteries have one plate with PbO₂ and the other one Pb. Discharged batteries have both plates PbSO₄. So neither one is pure lead. The electrolyte is sulfuric acid, more concentrated when the battery is charged." Does this mean that there is no metallic lead at all in USP system batteries when there is a failure in a fire and that only the powder PbSO₄. would leak out in the fire, so there would not be any metallic lead at all on the floor in a violent fire if the fire melted the USP systems with the batteris so they discharged?. Could i write in my paper that in a fire, only the powder PbSO₄. would pour out on the floor and no metallic lead would pour out at all?.

It's not pure lead but a lead alloy...

..."The grid structure of the lead acid battery is made from a lead alloy. Pure lead is too soft and would not support itself, so small quantities of other metals are added to get the mechanical strength and improve electrical properties. The most common additives are antimony, calcium, tin and selenium. These batteries are often known as “lead-antimony” and “lead­calcium.”"...

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

So is this lead alloy someting special that you cant buy anywhere?, how much lead is there in the alloy, 70-80% or less?, how many KG of molten metallic lead do you think could be leaked out on the floor in a fire if you look at my picture of the USP system room, i need to find out a credible estimate. And would this lead alloy behave and look in any different way when molten than pure lead would?.

These questions have all been answered, and if you're referring to an uninterruptible power supply, it's UPS....

No they havent, please answer them one at the time, i need answers for them all.

If you want to see if you can detect any difference between molten lead and molten lead antimony I suggest melt a piece of lead used for flashing and a number of tyre balance weights which have a small amount of antimony, maybe a few percent, separately and compare the molten puddles. The lead antimony is harder than lead and makes good shotgun shot and if water quenched becomes even harder.

When the led melts it will run along the floor until it cools and because of its SG it will be the bottom fraction in the flow.

You could take the conservative approach as follows.

Worst case solid lead: assume that all metal present is essentially "lead" and that this melts. It will solidify once goes below melting point and is easily recovered.

Worst case dissolved lead: The maximum dissolved lead will be in the electrolyte that will either evaporate in the fire (so oxides of lead remain in the space) or else presume a 100% electrolyte spill and that will provide details of necessary bunding.

In essence, that bunding would also contain the molten lead until it solidified.

Note that the surface tension of the molten lead might mean that it wouldn't flow anyway.

The "fire" that you propose will also produce some other "nasties" from the battery housings and the external wiring and such. The gasses given off from these is far more difficult to contain and might necessitate local evacuations.

"Note that the surface tension of the molten lead might mean that it wouldn't flow anyway."
Can you please explain how this works, why it wont flow away?, even in a hot fire?. Really need to understand this. Thanks in advance.

You will notice that if you pour a little water on a smooth floor, it forms a puddle with a raised edge. That is the meniscus and until the volume behind the edge is filled to a higher level, the puddle doesn't grow. Molten lead is similar. You could do a simple experiment with around 1kg of lead.

Thus, on a LEVEL floor, I would suspect that the puddle would be around 5mm thick before extending, so if you know the floor area you can calculate a volume.

In a past experience I used to recover lead, melt it and cast into the frog of a brick to make small ingots. I could overfill the mould by 5mm or more before it flowed across the surface of the brick.

For the interest of others here, Dad bought an old overhead telephone line to recover the wires as scrap copper and the CCA poles to build a shed. The threaded heads inside the insulators were cast lead on a steel/iron bolt on most of them. The REALLY old ones were threaded timber. I threw the insulators away. They now sell for a few bucks each to collectors and farmers setting electric fences.

So with the force of gravity in a fire it would not be likely that it flows a long way away from the heat source?.

The outcome would be determined by the individual geometry of each case. A sloping floor would probably direct the molten material in that direction.

A lip at the doorway would cause a local "dam".

It will only flow until it solidifies (away from the heat source)

The hotter the molten material is, then the more "liquid" it would become and flow more easily, but once it reaches material that cools it to solid, then the next "wave" would need to overtop that and so on. A little like candle wax running down the side of a candle. It doesn't run forever, but solidifies into wonderful artistic forms and then the next flow goes that little bit further and so on.

It will likely flow downhill until it solidifies, much as volcanic lava does.

The original thread is about the safety of such things. Is the fire intended or unintended (rhetorical question)? Precautions need to be in place to limit and eliminate harm so far as is reasonably practicable.

<...fire when the batteries are destroyed...total amount of metallic lead that would leak out...>

An agenda:

• Assume all of it, and design a secondary containment bund into place to catch it. It is usual to assume 110% of volume of materials for any bund arrangement.
• Seek the advice of the local Fire Authority, by arranging a site visit and a report from an individual fluent in fire prevention techniques.
• Consider the ventilation arrangements within the <...room...> so as to prevent the <...lead...> and its vapours from being released outside the <...room...>.
• Consider the use of <...fire...> suppression systems so as to reduce or eliminate the damage that initiation of conflagration could produce.
• Consider eliminating flammable materials within the <...room...> that might add to any <...fire...>.
• Consider reducing the potential for <...fire...> to start by reviewing and improving the electrical arrangements with the <...room...>, making sure all is up-to-local-code.
• Consider the adequacy of training of those involved with the facility so as to make <...fire...> by their acts and omissions a more remote possibility.