Chemical protection of a lithium surface

A method of providing a chemical protective layer on a metal, comprising:

• introducing an alkali metal into a reaction chamber;
• introducing one or more precursors of the protective layer into the reaction chamber and into contact with a first surface of the metal;
• and
• conducting a reaction involving the one or more precursors to form the chemical protective layer on the metal;
• wherein the protective layer comprises an alkali or alkaline earth metal carbonate.

A method of providing a chemical protective layer on a negative metal electrode, comprising:

• forming and placing in a battery cell package an electrochemical structure comprising,
• a negative electrode comprising an alkali metal,
• a positive electrode,
• a separator disposed between the negative and positive electrodes, and
• current collectors on the negative and positive electrodes;
• introducing a liquid electrolyte or catholyte comprising one or more precursors of a protective layer into the battery cell package and into contact with an exposed surface of the negative metal electrode;
• and
• conducting a reaction involving the one or more precursors to form the chemical protective layer on the exposed surface of the negative metal electrode;
• wherein the protective layer comprises an alkali or alkaline earth carbonate.

A battery cell, comprising:

• an negative metal electrode a negative electrode comprising an alkali metal and having a protective layer on an electrolyte exposed surface;
• a positive electrode chosen from a sulfur-based positive electrode, a metal oxide based positive electrode, and a metal sulfide based positive electrode;
• an electrolyte disposed between the negative and positive electrodes;
• and
• current collectors on the negative and positive electrodes;
• wherein the protective layer comprises an alkali or alkaline earth metal carbonate.