(Invited) Saft Gen 6 Electrochemistry for GEO/LEO Application

Abstract

Satellite battery industry is facing a serious material obsolete issue. The MCMB anode and NCA cathode active materials were no longer available. Saft developed a Generation 6 space cell –VL51ES which addressed material obsolescence in the space industry and provided high specific energy to meet the demands of today’s space missions. The selected electrodes electrochemistry provides excellent storage and cycle life. VL51ES is an iteration of proven technology and a legacy of failure-free batteries with up to 18 years in space. Manufactured in both France and the US, the redundant manufacturing capability ensures effective product delivery to customers across the globe. Saft incorporated advanced technology and enhanced manufacturing processes. Compared with the previous generations of space cells, the Gen 6 space cell is more industrialized, efficient and cost effective. Change from tabbed design to tabless design significantly reduces cell impedance, it makes VL51ES capable for higher rate discharge and cold temperature charge than previous Saft space cells. It represents a 20% height reduction along with a 10% improvement in energy. This cell has excellent GEO mission life, 45 accelerated GEO seasons were demonstrated with only 6% total energy loss. VL51ES passed voltage reversal tests without safety event, it enables a by-pass less battery design to reduce cost and complexity at battery level and maintain the same reliability. The qualification of VL51ES covers a full range of space requirements including safety, electrical, mechanical, abuse, life test and reliability. A data package has been compiled for customers with records of all test results. The qualification data is incorporated into Saft’s Li ion model (SLIM) which help customers to predict battery life performance at different scenarios and help customer with proper battery sizing.