IEC 62984-3:2020 specifies performance requirements and test procedures for high­-temperature batteries based on sodium for mobile and/or stationary use and whose rated voltage does not exceed 1 500 V. Sodium based batteries include sodium-sulphur batteries and sodium-nickel chloride batteries; both are high-temperature batteries and use a solid, sodium conducting electrolyte. Additional information on sodium-based batteries technology, their chemistries and construction are given in Annex B. This document does not cover aircraft batteries, covered by IEC 60952 (all parts), and batteries for the propulsion of electric road vehicles, covered by IEC 61982 (all parts).