Abstract: An electrode active material mainly includes an organic compound having, in a structural unit thereof, a conjugated diamine structure represented by the general formula (I), and an electrolyte includes a carbonate ester compound represented by the general formula (II). In the formulae, R1 to R4 represent substituted or unsubstituted alkyl groups, or the like, whereas X1 to X4 represent a hydrogen atom or a substituent. A secondary battery is achieved which has a high energy density and thus produces a high output, and has favorable cycle characteristics with a small capacity degradation even in the case of repeating charge and discharge.

Abstract: An Ni-free white copper alloy of formula CuaZnbTic or CuaZnbTicXd wherein X is at least one element selected from the group consisting of Al, Sn, Ag and Mn, b, c and d are, in mass %, 0.5≦b≦30, 1≦c≦7 and 0.1≦d≦4, and a is the balance, with unavoidable elements, and also a producing method therefor, comprising: preparing a material alloy for the above white copper alloy; heating the alloy to 700 to 885° C.; and cooling the alloy. The Ni-free white copper alloy has a strength and excellent hardness comparable to those of nickel silver, as well as excellent workability, corrosion resistance and whiteness in addition to ductility, and is free from an Ni allergy problem because of containing no nickel, and moreover tends not to cause needle detectors to malfunction.