The element lithium is a silvery-white metal that is less dense than water, making it one of the lightest solid elements at room temperature (although it is only two-thirds as dense as sodium and about half as dense as liquid nitrogen). It forms salts with all halides, including LiF, LiCl, LiBr, and LiI. These compounds are known as lithium salts, and they are the major products from lithium ores. Lithium carbonate is the most important of these, and it is used in batteries and ceramics. Lithium has a very low melting point and boiling point. It is the only alkali metal that can be vaporized, and it can form liquids at very low temperatures. Lithium is very reactive, however, and it reacts rapidly with oxygen in air at ambient pressure. The reaction is usually explosive, and the gas produced is flammable. It is also possible for the metal to react with nitric acid.
In battery applications, lithium has been used in the anode to store energy. However, in the current lithium-ion batteries, this element is typically provided in the form of a thin sheet of lithium metal oxide. This has limited the choice of anode host materials and reduced the maximum energy density that can be achieved using lithium chemistry.
The present invention provides a stabilized lithium metal powder that can be used as an alternative to thin lithium foil. It is produced by heating lithium metal to a temperature above its melting point, agitating the molten metal, and contacting it with a fluorination agent to provide stabilized lithium metal powder. This material has been tested for pyrophoricity (method 1050 of the DOT regulations for transport of spontaneously combustible materials) and found to be non-pyrophoric. It has also been shown to be stable in selected solvents and is being used in lithium-ion batteries with promising results.