A normal lithium ion cell doesn't contain any metallic (elemental) lithium. The chemicals are usually a lithium salt like lithium perchlorate or lithium hexafluorophosphate dissolved in a suitable organic solvent mixture such as ethylene carbonate and dimethyl carbonate. The electrodes are typically lithium cobalt oxide (positive) and graphite(negative) but vary widely. None of the above chemicals is particularly air-sensitive. The danger comes from two things: the high energy density of the cell such that even a tiny short circuit internal to the cell can cause extreme heating and also the flammability of the electrolyte. The lithium compounds play only a minor role in the combustion (they can turn the flames bright red from the characteristic emission spectrum of Li(+) ions) It is a very active area of research to find a suitable non-flammable solvent for lithium ion battery electrolyte - to substitute for the organic carbonates and other solvents used now. Unfortunately the solvent needs to have certain properties which greatly reduce the number of suitable solvents. Water cannot be used - not because of reaction with lithium - but because the cell voltage is too high and it would immediately begin breaking the water apart into hydrogen and oxygen. In fact, you absolutely should consider using water to put out a lithium ion battery fire, as long as there is no high voltage present (such as a line-powered battery charger) which could cause a shock hazard to the person pouring the water. Some of the confusion in this topic comes from the existence of lithium primary batteries. These are non-rechargable and DO contain elemental lithium. Examples of these are 3V button cells (like the CR-series) and long-term memory or clock backup batteries. Some critical medical or military equipment can contain fairly large lithium primary cells - like some automated external defibrillators. The chemistry also varies greatly but the traditional main example is the lithium manganese dioxide cell, which has lithium metal as the anode, MnO2 as the cathode, and a solution of lithium perchlorate in an organic solvent as the electrolyte. These will react violently if the inside of the cell is exposed to water. They will also react with oxygen in air (if the seal is broken) but much more slowly. However, their lithium anode can certainly burn in air with a very hot flame if it is ignited and the electrolyte is once again very flammable, too. On Thu, Aug 2, 2018 at 5:29 PM, smplx wrote: > > > On Thu, 2 Aug 2018, Richard Pope wrote: > > > James, Ryan, > > What has happened is a cascade failure. Remember that a battery is > > made of several cells. When one of these cells failed it overheated the > > cells around it. This caused these cells to fail and this overheated > > surrounding cells and so forth. The lithium in the batteries would reac= t > > in a violent manner to the oxygen in the air when the cells were > > breached. Once this type of failure starts there is no way to stop it. > > Actually, if I remember correctly, it's not the oxygen in the air that's > the problem but the composition of the electrolyte. Some chemistries are > happy to oxidise the lithium without the need for atmospheric oxygen. > > Regards > Sergio Masci > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .