Elektrischer Akkumulator

摘要

1,199,393. Electric cell using reversible hydride formation. BATTELLE MEMORIAL INSTITUTE. 6 Feb., 1968 [7 Feb., 1967], No. 5961/68. Heading H1B. A cell in which electrochemical energy is stored by reversible hydride formation comprises a negative and a positive electrode each immersed in electrolyte in compartments separated by a porous wall, the reactive material of the negative electrode being a suspension in the electrolyte of particles of a metal which are in hydride form when charged and which oxidize to form water on discharge, said porous wall being permeable to electrolyte and impermeable to the particles and inert to electrolyte and to oxidizing and reducing agents. Suitable metals for the particles include Pd, Th, Fe, Co, Ni, Ti, Zr, V and Ce; alloys containing 60-95 wt. per cent Ti with Ni and optionally Pt, Pd, Cu, Ag, V, Zn and A1 are preferred. The positive electrode may be an air or oxygen electrode, or may comprise as active material particles of a reversible oxideforming metal e.g. Ag, Mu or Hg, preferably Ag doped with Ce. The discharge electrodes (above) may be of Ni ; charge electrodes, where used may be of Cd or e.g. Su amalgam (negative) or of Ag or Ag alloy (positive side). In Fig. 2 particles of an alloy of Ti/Ni/Cu (74/20/6 wt. per cent) hydride in container 11, and particles of Ag oxide in container 12, flow during discharge, when valves 17 and 19 are opened through the negative and positive electrode compartments 3 and 4, which contain aqueous KOH and are separated by a porous polyolefine wall, past discharge electrodes 5 and 6 of Ni, via ducts 18 and 20 into containers 13 and 14 for the spent alloy and silver particles. During charging valves 17 and 19 are closed and pumps 21 and 22 move the particles from containers 13 and 14 to compartments 3 and 4, wherein a P.D. is applied to charge electrodes 7 and 8, of Cd and Ag respectively, and thence via ducts 15 and 16 to storage containers 11 and 12. In Fig. 3 the wall 21 surrounds the Ag-activated graphite porous electrode 33 which is connected to air compressor 34, CO 2 filter 35 and conductor 36; the discharged alloy particles are pumped via duct 25 to separator 26, whence the particles alone proceed to regenerator 28 in which they are heated in H 2 at 300-400‹ C. and 10 atm., by heater 29, and thence to mixer 30 wherein they are returned to the electrolyte and are pumped by pump 32 via duct 31 to container 11.