68848-64-6

Basic information

• Product Name: Lithium silicon
• Synonyms: Lithium silicon;Lithium alloy, nonbase, Li,Si;Silicon alloy, nonbase, Li,Si
• CAS NO: 68848-64-6
• Molecular Formula: H4LiSi
• Molecular Weight: 39.05826
• Mol File: 68848-64-6.mol
• Article Data: 4

Chemical Properties

• Appearance: /
• CAS DataBase Reference: Lithium silicon(CAS DataBase Reference)
• NIST Chemistry Reference: Lithium silicon(68848-64-6)
• EPA Substance Registry System: Lithium silicon(68848-64-6)

Safety Data

• RIDADR: UN 1417
• HazardClass: 4.3
• PackingGroup: II
• Hazardous Substances Data: 68848-64-6(Hazardous Substances Data)

Usage

General Description

A black lustrous powder or cohesive lump with a sharp irritating odor. An alloy of lithium and silicon.

Air & Water Reactions

Reacts with water or moisture in air to form lithium hydroxide and hydrogen, a flammable gas. The heat of the reaction may ignite the hydrogen [AAR 1991].

Reactivity Profile

Lithium silicon is a reducing agent. Reacts with oxidizing agents. Reacts, usually vigorously, with any substance having active hydrogen atoms to liberate gaseous hydrogen. This includes alcohols, acids, and water. Reacts with sulfides,aldehydes, and cyanides. Corrodes rapidly on contact with the air. As a practical matter, most organic compounds, including ethers, are wet enough (carry enough water as an impurity) to cause heating and liberation of gases.

Health Hazard

Inhalation or contact with vapors, substance or decomposition products may cause severe injury or death. May produce corrosive solutions on contact with water. Fire will produce irritating, corrosive and/or toxic gases. Runoff from fire control may cause pollution.

Fire Hazard

Produce flammable gases on contact with water. May ignite on contact with water or moist air. Some react vigorously or explosively on contact with water. May be ignited by heat, sparks or flames. May re-ignite after fire is extinguished. Some are transported in highly flammable liquids. Runoff may create fire or explosion hazard.

Safety Profile

A very dangerous fire hazard in the form of dust when exposed to heat or flame or by chemical reaction with moisture or acids. In contact with water, silane and hydrogen are evolved. Slightly explosive in the form of dust when exposed to flame. Will react with water or steam to produce flammable vapors; on contact with oxidizing materials, can react vigorously; on contact with acid or acid fumes, can emit toxic and flammable fumes. To fight fire, use CO2, dry chemical. See also LITHIUM, SILICON, and POWDERED METALS.

InChI:InChI=1/Li.Si/q+1;+4

Upstream product

• 7439-93-2 lithium 
• 7440-21-3 silicon 

Relevant articles and documents

Site-Specific Substitution Preferences in the Solid Solutions Li12Si7–xGex, Li12–yNaySi7, Na7LiSi8–zGez, and Li3NaSi6–vGev

The mixed silicide-germanides Li12Si7–xGex, Na7LiSi8–zGez, and Li3NaSi6–vGevwhich could serve as potential precursors for Si1–xGexmaterials were synthesized and characterized by X-ray diffraction methods. The full solid solution series Li12Si7–xGex(0 ≤ x ≤ 7) is easily accessible from the elements and features preferential occupation of the more negatively charged crystallographic tetrel positions by Ge, which is the more electronegative element. In case of Na7LiSi8–zGeza broad solid solution range of 1.3 ≤ x ≤ 8 is available but the ternary silicide Na7LiSi8could not be obtained by the tested methods of synthesis. The solubility of Ge in Li3NaSi6–vGevis highly limited to a maximum of v ≈ 0.5, and again the formally more negatively charged tetrel positions are preferred by Ge. Additionally, the two crystallographic Li positions in Li12Si7with unusually large displacement parameters can be partially substituted by Na in Li12–yNaySi7with 0 ≤ y ≤ 0.6. The statistical mixing of Li and Na in this solid solution contrasts the typical ordering of Li and Na in most ternary tetrelides.

Accelerating rate calorimetry studies of the reactions between ionic liquids and charged lithium ion battery electrode materials

Using accelerating rate calorimetry (ARC), the reactivity between six ionic liquids (with and without added LiPF6) and charged electrode materials is compared to the reactivity of standard carbonate-based solvents and electrolytes with the same electrode materials. The charged electrode materials used were Li1Si, Li7Ti4O12 and Li0.45CoO2. The experiments showed that not all ionic liquids are safer than conventional electrolytes/solvents. Of the six ionic liquids tested, 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide (EMI-FSI) shows the worst safety properties, and is much worse than conventional electrolyte. 1-Ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (EMI-TFSI) and 1-propyl-1-methylpyrrolidinium bis(fluorosulfonyl)imide (Py13-FSI) show similar reactivity to carbonate-based electrolyte. The three ionic liquids 1-butyl-2,3-dimethylimidazolium bis(trifluoromethanesulfonyl)imide (BMMI-TFSI), 1-butyl-1-methylpiperidinium bis(trifluoromethanesulfonyl)imide (Pp14-TFSI) and N-trimethyl-N-butylammonium bis(trifluoromethanesulfonyl)imide (TMBA-TFSI) show similar reactivity and are much safer than the conventional carbonate-based electrolyte. A comparison of the reactivity of ionic liquids with common anions and cations shows that ionic liquids with TFSI- are safer than those with FSI-, and liquids with EMI+ are worse than those with BMMI+, Py13+, Pp14+ and TMBA+.