Thiocarbohydrazides and Oxalyl Dihydrazides Exhibiting Two- to Four-electron Redoxes for Positive Electrode Active Materials in Organic Rechargeable Lithium Batteries

Thiocarbohydrazides and oxalyl dihydrazides are used as positive electrode active materials for rechargeable lithium batteries with a lithium metal negative electrode. These compounds exhibit a two-electron migration in the positive electrode, yielding very large capacities of 482 and 450 mA h g(-1) respectively, by virtue of their small molecular weights (106 and 118, respectively). Additionally, tetramethyl- and diphenyl-substituted derivatives are used; the former compounds exhibit two-electron migrations with capacities of 310 and 300 mA h g(-1) while the latter compounds exhibit three- to four-electron migrations with large capacities of both 359 mA h g(-1).