NON-AQUEOUS LITHIUM-PYROMELLITIC DIANHYDRIDE CELL

The new lithium/1 M LiClO4 propylene carbonate/pyromellitic dianhydride (PDA) cell and the improved Li/PDA cell are presented. The Li/PDA cell system has an open circuit voltage of 3.1-3.2 V, and 0.246 Ah g-1 theoretical capacity, which is based on two-electron transfer. When the pyromellitic acid (PA), which is insoluble in the electrolyte, is added in PDA cathode as proton donor, the specific capacity is roughly two times than that of PDA. The cathode of such improved Li/PDA cell consists of 42 wt% of PDA, 18 wt% of PA and 40 wt% of acetylene black. Such improved Li/PDA cell has about 1300 Wh kg-1 of energy density. The cell performance of the improved Li/PDA cell is examined, and the self-discharge test is also done and proved the capacity loss to be negligible during two weeks of storage in spite of the solubility of PDA (0.07 mol l-1) in an electrolyte solution. © 1979.