Lots of divergent opinions, both valid, but I lean towards noting that the vast majority of lithium batteries in use today are the rechargable ones, and they are not really lithium fires when they burn, as some here have implied. They are not Class D fires. They are fire hazards, for sure, but due to their flammable fluids, the electrolyte, I think. As such, it is much easier (relatively) to extinguish fires involving these batteries.

It all comes down to dealing with the fire rapidly. As Shakespeare said in Henry the IV - Act IV, "A little fire is quickly trodden out, which being suffered, rivers cannot quench."

Just some background on the lithium batteries - in the early 1980s lithium batteries came on the scene. And "Violent Outgassing" was too nice a phrase to describe things that they did. A handy "Self Destruct" mechanism was to put current into the lithium battery pack. Pow!

There were "sonabouy" devices that needed the extra power of the lithium battery, but the aviators really didn't want them inside the aircraft. They were persuaded that the hazard would be acceptable if the devices were carried on the outer wing pylons. Fortunately, there were no explosions. There was a story (I can not confirm it) that a box exploded in a warehouse and killed a man behind a brick wall.

Today's lithium batteries use a different chemistry, and were for a while at least, considered safe... They still have the warning "Do Not Attempt To Recharge This Battery". I haven't tried it, yet, but the adolescent in me wants to see how big a bang I can get out of a spent camera battery...

On the other hand, a "Lithium Lick" refers to someone who can calm upper management, and lithium chloride is used to treat bi-polar mental conditions.

You referred to the at-risk batteries as "primary" batteries; but the CR2s I use in cameras are not primary, but rechargeable types. Was the reference to "primary" batteries a slip-up, do are the risks, or at least greater risks, relate mainly to the primary or non-rechargeable batteries?

What about Li-Polymer cells? Are these safer than Li-Ion? Or do they share some of the same construction and internal membrane materials?

Were the batteries or the laptop computers which employed the batteries UL Listed? Were there tests which, if performed, would have prevented the fires by requiring manufacturing or design requirements in the applicable UL Standard? Or CSA or IEC standard? I have not fully read this article yet, but skimmed it while I was still connected to the site and did not yet see UL or other agencies mentioned.

First of all. A battery management system can't detect or stop this kind of LION pack fire.

A LION cell is like a "jelly roll" It has two sides seperated by a membrane.

A dirty secret of the LION industry is the seperator or "isolator" or membrane in the cells are punctured due to metal shavings or other "impurities". When the puncture happens, a burn starts. Most of the time the burn stops. You have a small spot in the cell and slightly reduced capacity. You would never know it happened unless you "unrolled" the cell to see it. But, sometimes this burn doesn't stop and the cell is consumed.

This is TOTALLY different from a cell rupture caused by overcharging. The only thing the battery management circuit inside the battery can do is turn off the charge current, turn off the supply of current from the battery and the outside world, and if necessary, blow a fuse inside that isolates the cells completely from the outside world connector. If the cell is burning internally, there's nothing the management circuit inside the battery can do other than wait to be burned up.

There is a new seperator technology that will greatly resist punture and if a puncture happens will self arrest the burn. Sony wasn't the company that had this technology when I learned of it. I can't say who had it either but you can problaby find out by now.

Lithium!! WOO HOO!! Burns Extremely HOT! Spray water on it and it burns even better!! Anything that will contribute a combustible (oxidizable) substance will increase the "flame factor". Smothering in lots of sand will at least keep the flames contained.

The only way to put out a lithium fire is with a Class D extinguisher, the most effective ones use copper since the metal helps cool the lithium pile and reduce the temperature below the self ignition point. While some Class D extinguishers use salt, they are generally not as effective since the salt will not cling to vertical surfaces.

How to fight a Class D fire

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ The National Fire Protection Association (NFPA) classifies fires into five general categories (U.S.):

* Class A fires are ordinary materials like burning paper, lumber, cardboard, plastics etc.

* Class B fires involve flammable or combustible liquids such as gasoline, kerosene, and common organic solvents used in the laboratory.

* Class C fires involve energized electrical equipment, such as appliances, switches, panel boxes, power tools, hot plates and stirrers. Water can be a dangerous extinguishing medium for class C fires because of the risk of electrical shock unless a specialized water mist extinguisher is used.

* Class D fires involve combustible metals, such as magnesium, titanium, potassium and sodium as well as pyrophoric organometallic reagents such as alkyllithiums, Grignards and diethylzinc. These materials burn at high temperatures and will react violently with water, air, and/or other chemicals. Handle with care!!

* Class K fires are kitchen fires. This class was added to the NFPA portable extinguishers Standard 10 in 1998. Kitchen extinguishers installed before June 30, 1998 are "grandfathered" into the standard.

# CO2 (carbon dioxide) extinguishers are for class B and C fires. They don't work very well on class A fires because the material usually reignites. CO2 extinguishers have an advantage over dry chemical in that they leave behind no harmful residue. That makes carbon dioxide (or Halotron I; see below) a good choice for an electrical fire involving a computer or other delicate instrument. Note that CO2 is a bad choice for a flammable metal fires such as Grignard reagents, alkyllithiums and sodium metal because CO2 reacts with these materials. CO2 extinguishers are not approved for class D fires!

Look! To get an idea for what could happen, take a look at this General Chemistry demonstration page that includes a QuickTime movie of a magnesium metal fire contained inside a block of solid CO2!

# Metal/Sand Extinguishers are for flammable metals (class D fires) and work by simply smothering the fire. The most common extinguishing agent in this class is sodium chloride, but there are a variety of other options. You should have an approved class D unit if you are working with flammable metals. The following types of class D extinguishing units are available through our on-line store, Safety Emporium.

* Sodium chloride (NaCl) works well for metal fires involving magnesium, sodium (spills and in depth), potassium, sodium/potassium alloys, uranium and powdered aluminum. Heat from the fire causes the agent to cake and form a crust that excludes air and dissipates heat.

* Powdered copper metal (Cu metal) is preferred for fires involving lithium and lithium alloys. Developed in conjunction with the U.S. Navy, it is the only known lithium fire fighting agent which will cling to a vertical surface thus making it the preferred agent on three dimensional and flowing fires.

* Graphite-based powders are also designed for use on lithium fires. This agent can also be effective on fires involving high-melting metals such as zirconium and titanium.

* Specially-designed sodium bicarbonate-based dry agents can suppress fires with most metal alkyls, pyrophoric liquids which ignite on catact with air, such as triethylaluminum, but do not rely on a standard BC extinguisher for this purpose.

* Sodium carbonate-based dry powders can be used with most Class D fires involving sodium, potassium or sodium/potassium alloys. This agent is recommended where stress corrosion of stainless steel mus be kept to an absolute minimum.

This article is very misleading. Li-Ion rechargeable (secondary) cells ARE NOT the same as lithium primary cells. Li-Ion cells do not contain metallic lithium as do lithium primaries. If abused over time lithium-ion cells may form metallic lithium along the electrodes but not in large enough quantities to be a major hazard. The real problem is with the flammable electrolytes (which Halon could easily extinguish).

To put this in perspective, I’m sure many more people have been burned in the past by accidentally shorting a fully functioning NiCad battery pack then will ever be by malfunctioning Li-Ion laptop pack.

I am willing to give this author some time on this subject. The terminology can be misleading.

Rather than try to explain the whole matter in this message, it is sufficient to say that most of the author's citations come from narratives about PRIMARY Lithium Batteries. PRIMARY batteries are, essentially, throw-aways. That's because the chemical process inside is irreversible. In other words, they cannot be recharged. Once they are used up, they are tossed.

Dell's problems occurred with a type of Secondary Battery called "Lithium-Ion". Such batteries are rechargeable. The chemistry of these babies is sufficiently different to make the "Lithium" narrative inapplicable.

It is possible that a sufficiently sophisticated battery management system could have caught this problem as it was developing. If the migrating precipitates cause a cell imbalance, or a dramatic loss of capacity over a recharge cycle, a smart fuel gauge system could detect this and report it to the OS. The OS could trigger a user warning and the smart battery manager could declare Permanent Failure in the Battery (which leads to a permanent shutdown of all control FETs).

Let's reload on this story, and see what happens.

With kindest regards, Michael A. Banak

Excellent information for the general public.

One obvious thing that battery users can do is become educated about containing a lithium fire. Wrapping or enclosing it in something that won't burn. Concrete floors do not burn. A website dedicated to battery safety would be nice. Maybe battery makers could be lobbied privately ( no government , please ) to create such a site.

Really interesting! Sorry to note a mis-statement: From: “The ignition of primary lithium batteries ..." the author go to "Extrapolating from CR2s to laptop batteries suggests that a laptop fire is not a trivial event." It's not the same kind of event: the "primary" lithium batteries are typically Li-MnO2, who exibit the release of oxigen to substain the exotermic reaction. The Li-ion or Li-pol batteries into laptops have a different chemical and behaviour (not totally safe, but sustantially different).