The electrical properties of polycrystalline copper(I) bromide were investigated between 20 and 430 degrees C by impedance spectroscopy with copper electrodes. Extrinsic and intrinsic regions in gamma-CuBr and a domain of fast ionic conduction in beta-CuBr are separated. Enthalpies of migration of copper interstitials (25 kJ/mol) and copper vacancies (50 kJ/mol) and the enthalpy of formation of Frenkel defects (160 kJ/mol) are deduced. The phase boundary copper/copper(I) bromide can be represented by a parallel circuit of an interfacial resistance and a constant phase-angle (CPA) element. The interfacial resistance depends exponentially on temperature and is practically negligible above 350 degrees C. Contributions of charge transfer resistance and space charge resistance are discussed. Prefactors of CPA elements depend also exponentially on temperature; they are compared with interfacial capacitances.