Extover® as an extinguishing agent and for preventive fire protection

In the last one hundred years, researchers and developers have been particularly interested in using lithium in batteries. Lithium is a light metal with a high specific capacity (3.86 Ah/g) and unique electrochemical characteristics. But handling lithium is challenging. It reacts with humid air and especially intensely with water. Its melting point is only 356° F.

Possible hazards during the energy-intensive production of lithium batteries include thermal runaway due to internal short circuits, the discharge of electrolyte and overloading. Lithium batteries can develop very high temperatures, thereby igniting other batteries in a sort of chain reaction.

Lithium reacts with water

Due to the high reactivity of lithium with moisture, the use of water as an extinguishing agent is not recommended. The carbon contained in lithium can react with water in case of fire. When lithium reacts with the electrolytes and the extinguishing water, hydrogen can be produced. This hydrogen may form ignitable mixtures with the ambient air and burn abruptly. Re-ignition may also occur. Subsequent cooling of a fire is therefore required, resulting in a much higher consumption of extinguishing water.

Extover® as a dry extinguishing agent

Extover® is ideal as a dry extinguishing agent and especially well suited for processes where the use of extinguishing water or foam is not possible, for example the aging of lithium batteries. The extinguishing capacity of Extover® on lithium battery fires was tested by MPA Dresden. The result: all fire objects could be extinguished with Extover®. Here the extinguishing effect is based on isolation (encapsulation) and suffocation.

The Extover® effects

Suffocation effect – oxygen is displaced and separated from the fuel.

Cooling effect – Extover® absorbs heat energy, cools the fire and disrupts the thermal reaction.

Gas tightness – the round grains flow readily, surround the fire load and impede the supply of oxygen.

Sorbency of liquids – the granulate mixture effectively binds liquids.

Filter effect – gases and vapours accumulate on the surface of Extover® and are bound for disposal.