From what I gather, it’s primary cells, particularly nasty.
I did see some second rate journalism on one of the major news sites that said the fire fighters used sand due to metallic lithium reacting with water… then went on and padded the story with “lithium batteries are commonly used in electric vehicles, powertools, laptops and cellphones”
Not primary cells, you donkeys 
22 fatalities is horrible.
You’d think that safety precautions would prevent that sort of incident and loss of life. Seems like a sketxhy operation for South Korea. Also, there’s dry chemical retardants that can put out lithium fires. Why didn’t the firefighters have that? Sad.
CCTV footage capturing the moment the fire started at a lithium battery factory.
Holy cow, they tried to stop a runaway lithium fire involving what looks like hundreds of batteries with a dinky ABC fire extinguisher? You need to drop everything and RUN. Sound the alarm and run. These batteries should have been safely stored!
In hindsight they possibly should have kicked over the whole stacks to quickly get to the single (?) battery that started this and to stop the chain reaction.
I know, I know … it’s one thing to smartass from the safety of your chair and another thing to experience this live.
Well, i think lack of training was a huge factor here…that and improper storage. A trained individual would have immediately grabbed a c02 and dry chemical extinguisher and tried to extinguish or at least mitigate the fire to give others time to evacuate. These batteries shouldn’t have been stored this way anyway and the facility should have had a halon gas fire suppression system. This wouldn’t have happened the way it did with a large loss of life if those were followed. Shame. I hope the company owners are prosecuted and fined for the negligence.
I wonder if a runaway lithium battery fire could be extinguished (or even meaningfully slowed down) with a halon or dry ice extinguisher. Would cutting oxygen supply make much difference?
It turns out that the search for an agent and a method of extinguishing lithium-ion battery fires has been going on for a while. A Google Scholar search brings up quite a few papers on it. From what I gathered, water or water-based agents sprinkled in large quantities do the best job and traditional extinguishers are mostly ornamental.
Yeah, (immersion in) water just cools it down so it will eventually stop the reaction. Another easy solution is having big metal buckets with silica sand ready … and really long pliers to grab a burning cell and stuff in it there. Will not extinguish the fire nor stop it from spewing toxic smoke of course but it will contain the heat/fire.
It doesn’t rely on oxygen to fuel the combustion. Fire blankets should be deployed instead to contain the spread of the fire.
Might be good to have a rail system in place to eject the whole pallet out of the building at a flick of the switch.
Isn’t smoke from li-ion fires extremely toxic? Given that and the danger from the fire itself, I’d be hard pressed to stay and try and fight it.
In most building fire accidents, toxic fumes will knock the casualty out before the fire reaches them.
My admittedly limited understanding of breathing in the smoke is that there are or can be serious long term effects from it in. Looking at the video above I didn’t seen anyone wearing breathing equipment. So staying to fight a battery fire is not something that I would choose to do, all things being equal 
I believe the fumes from these primary lithium cells are even more nasty than li-ion but your point still stands.
The sound of the non-stop explosion is really scary.
Its super sad that these workers at the plant were doomed from the get-go with all of the safety failures and preventative measures for potential fires NOT in place. The S.Korean government needs to crack down in these smaller manufacturers to keep this from happening again. This would never happen at a Samsung or LG facility.