GB1360764A - Electrochemical cell - Google Patents

Abstract

1360764 Electric cells GTE LABORATORIES Inc 27 Dec 1972 [27 Dec 1971] 59714/72 Heading H1B An electrochemical cell has an active anode material consisting of an alkali metal, a Group IIIA element, or a rare earth element; a solid active cathode material consisting of a Group VIB element or a compound thereof with a metallic element; and an electrolyte comprising an inorganic solvent of formula P x O 2x-1 Cl +-2 where x = 1, 2, 3 or 4, and a solute which yields at least 10-<SP>3</SP> moles. litre<SP>-1</SP> each of anion and cation in the electrolyte. Suggested cathode materials are sulphur, selenium, cuprous oxide, cupric oxide, nickel oxide, lead dioxide, argentous oxide, argentic oxide, vanadium oxides, niobium oxides, tantalum oxide, manganese dioxide, chromium trioxide, cuprous sulphide, cupric sulphide, and nickel sulphide. These materials may be pressed into hollow-cylindrical or disc form, may be made more conductive with carbon or graphite fibres or silver particles, and may contain polyethylene, polypropylene or PTFE as binder. The anode materials lithium, sodium, potassium, the lanthanides, scandium, and yttrium may be contacted by a metal grid. For lithium anodes, grid materials may be nickel, coppernickel, stainless steel, silver, or platinum. The solvents specified are anhydrous phosphorus oxychloride (POCl 3 ) and pyrophosphoryl chloride (P 2 O 3 Cl 4 ) and mixtures of these. Suggested solutes are LiAlCl 4 ; LiBCl 4 ; LiBF 4 ; LiPF 6 ; LiAsF 6 ; LiSbF 6 ; LiSbCl 6 ; Li 2 SnCI 6 ; Li 2 ZrCl 6 ; Li 2 TiCl 6 ; LiSO 3 Cl; AlCl 3 ; BF 3 ; SnCl 4 ; SbCl 5 ; SbF 5 ; TiCl 4 ; AlBr 3 ; PF 5 ; PCl 5 ; AsF 5 ; AsCl 5 ; ZnCl 2 ; ZrCl 4 ; Lewis bases formed by the fluorides, chlorides, bromides, iodides, and oxides of Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, and the rare earth metals; materials yielding Cl-, Br-, I-, ICl 2 _, ClO 4- , and PO 2 Cl 2 - ions or adducts of the PO 2 Cl 2 - ion with ZrCl 4 , AlCl 3 , or BCl 3 ; materials yielding R 4 N+ (where R = methyl, ethyl, propyl, iso-propyl, butyl, or iso-butyl), POCl<SP>+</SP> 2 , or cations from Li, Na, K, Cs, Rb, Mg, Ca, Sr, Ba, La, Tb, Nd, Ce, Eu, or Sm. The cell may have a mechanical separator of alumina, beryllia, magnesia, zirconia, titania, porcelain, porous glass, fritted glass, or non-woven porous PTFE polypropylene or polyethylene, or may have an ion-selective membrane separator of zeolite or perfluorinated hydrocarbon sulphonate. In the 19 specific embodiments the anode is of lithium sheet, strip, or pieces and the solvent is POCl 3 . In most embodiments an electrolyte container of stainless steel is used which acts as a collector for a hollow cylindrical cathode. The cathode surrounds a glass-seal supported nickel mesh basket on to which is passed the lithium strip or sheet or which contains the lithium pieces. In one embodiment the container acts as anode collector for lithium strip and the nickel basket as cathode collector for selenium shot contained therein. Some embodiments use a disc cathode with a strip anode.