LITHIUM

   These cells are reactive and must be deactivated. First, the cells are cooled in a container of liquid nitrogen to reduce the reactivity of the lithium metal or other battery constituents during shredding and treatment.

   Following cooling, the batteries are shredded to expose the contents. Gases or fumes given off during shredding are treated in a scrubber system and the cleaned air is vented to the atmosphere. The shredded batteries are dumped into a large tank containing an alkaline solution where metallic lithium reacts with the water to form hydrogen gas. Lithium metal, ignited by the shredding action, or by reaction with the water in turn ignites the hydrogen evolved from the tank and forced venting serves to keep its concentration well below the explosive limit. The pH of the reaction solution is maintained by adding alkali to assist the soluble components of the battery to dissolve. As the concentration of these salts increases to the solubility limit, lithium salts precipitate from solution and are recovered.

   Scrap metal and plastic from the batteries are recovered from the treatment tank. The scrap can be separated into metallic and non-metallic fractions for recycle and/or disposal. The lithium salts are recovered and the clear solution is returned to the reaction tank. The recovered lithium salts are recycled. They may be used as an additive in concrete to prevent the alkali-silica reaction or they may be converted into high grade lithium carbonate for feed stock for the battery industry.