Performance and discharge characteristics of Ca/LiCl, LiNO3/LiNO3, AgNO3/Ni thermal battery cells

• Published in: Journal of the Electrochemical Society 1984-02, Vol.131 (2), p.283-286
• Main Authors: MCMANIS, G. E, MILES, M. H, FLETCHER, A. N
• Format: Article
• Language: English
• Subjects: Applied sciences; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Exact sciences and technology
• ISSN: 0013-4651; 1945-7111
• DOI: 10.1149/1.2115563

Thermal battery cells utilizing molten LiNO3 as an oxidizing electrolyte with calcium anodes have been characterized for high rate discharge conditions. The presence of small amounts of AgNO3 greatly improves the cathode reaction. Half-cell studies of anode characteristics show little variation of anode potential with temperature. Gasing at the anode-electrolyte interface increases with temperature and current density. Overall anode consumption rates increase with increasing temperature, while anode coulombic efficiencies drop at high rates of discharge (300 mA/sq cm). Cathode half-cell data reveal that high rate reduction of AgNO3 dissolved in LiNO3 yields masses of dendritic growth at low temperatures (260-275 C) while at higher temperatures (greater than 400 C) correspondingly fewer dendritic structures are observed. Cell experiments show anticipated current-voltage-temperature relationships, effectively mirroring half-cell experiments. Cell voltages sustain over 2V at 75 mA/sq cm for periods which vary according to temperature of discharge.