STRUCTURE AND ANODIC DISCHARGE BEHAVIOR OF LITHIUM-BORON ALLOYS IN THE LICL-KCL EUTECTIC MELT (II)

At temperatures above the melting point of lithium, anodes of lithium-boron alloys consist of a solid porous structure filled with nearly pure liquid lithium. The anodes are capable of being discharged at 4 A/cm2 and - 3V (vs. a chlorine reference electrode). During discharge, there are two very negative voltage plateaus with a small difference in voltage between them. At 8 A/cm2 the change in voltage over the combined plateaus is ±12% of the average voltage for the plateaus. The first plateau is terminated at three different anode compositions (Li6B, Li4B, and Li3B) depending on the initial anode composition. The second plateau is terminated when the anode's composition corresponds to Li2B. A more positive portion of the voltage curve terminates when the anode's composition corresponds to Li7B6. An alloy of 86 atomic percent (80 weight percent) lithium has a capacity of 7.6 MC/kg and 5.3 GC/m3, The alloys have superior lithium retention at 873°K compared with lithium-filled, nickel Feltmetal. © 1979, The Electrochemical Society, Inc. All rights reserved.