High temperature secondary cells

Claim 2

A high temperature secondary cell having: a. an anode pellet comprising a lithium alloy and an alkali halide electrolyte material including a lithium halide; p1 b. an electrolyte pellet comprising said alkali halide electrolyte material and an inert immobilizer selected from the group consisting of magnesia and boron nitride; c. a cathode pellet comprising said alkali halide electrolyte material and an active material selected from the group consisting of iron sulphide, iron disulphide and titanium disulphide; d. an electrically insulating, inert tube within which the above-mentioned pellets are arranged, the inert tube fitting closely around said pellets; and e. a respective electrical contact plate for each electrode pellet, said contact plates bounding the cell at each end and extending beyond the inner peripheral surface of the inert tube.

Claim 3

A high temperature secondary cell as claimed in claim 1 in which at least one of the anode pellet and the cathode pellet contains an inert immobilizer selected from the group consisting of magnesia and boron nitride.

Claim 4

A high temperature secondary cell as claimed in claim 1 in which said lithium alloy is a 20 wt% lithium/80 wt% aluminum alloy, and in which the anode pellet consists of 60-90 wt% of this alloy, the balance being said electrolyte material.

Claim 5

A high temperature secondary cell as claimed in claim 3 in which the anode pellet is compressed to between 60 and 90% of theoretical density.

Claim 6

A high temperature secondary cell as claimed in claim 4 in which said inert tube is of material selected from the group consisting of magnesia and boron nitride.

Claim 7

A high temperature secondary cell as claimed in claim 5 in which the electrical contact plates are of molybdenum.

Claim 8

A high temperature secondary cell as claimed in claim 1 in which the cathode pellet comprises 60 to 70 wt% of iron sulphide or iron disulphide, and the balance of said electrolyte material.

Claim 9

A high temperature secondary cell as claimed in claim 7 in which said cathode pellet is compressed to between 55 and 75% of its theoretical density.

Claim 10

A high temperature secondary cell as claimed in claim 8 in which said inert tube is of a material selected from the group consisting of magnesia and boron nitride.

Claim 11

A high temperature secondary cell as claimed in claim 9 in which the electrical contact plates are of molybdenum.

Claim 12

A high temperature secondary cell as claimed in claim 1 in which the inert tube is of a material selected from the group consisting of magnesia and born nitride.

Claim 13

A high temperature secondary cell as claimed in claim 1 in which said alkali halide electrolyte material comprises a mixture of lithium fluoride, lithium chloride and lithium bromide.

Claim 14

A high temperature secondary cell as claimed in claim 12 in which the electrolyte pellet contains 60-70 wt% of an immobilizer selected from the group consisting of magnesia and boron nitride; the balance being electrolyte material.

Claim 15

A high temperature secondary cell as claimed in claim 13 in which the electrolyte pellet is compressed to 60-70% of theoretical density.

Claim 16

A high temperature secondary cell as claimed in claim 14 in which the inert tube is of a material selected from the group consisting of magnesia and boron nitride.

Claim 17

A high temperature secondary cell as claimed in claim 15 in which the cathode pellet comprises 60-70 wt% of iron sulphide or iron disulphide, and the balance of said electrolyte material.

Claim 18

A high temperature secondary cell as claimed in claim 16 in which the lithium alloy is a 20 wt% lithium/80 wt% aluminum alloy, and in which the anode pellet consists of 60-90 wt% of this alloy, the balance being said electrolyte material.

Claim 19

A high temperature secondary cell as claimed in claim 17 in which the cathode pellet comprises 60-70 wt% of iron sulphide or iron disulphide, and the balance of said electrolyte material.

Claim 20

A high temperature secondary cell as claimed in claim 18 in which the electrical contact plates are of molybdenum.

Claim 21

A high temperature secondary battery comprising a plurality of cells each cell having: a. an anode pellet comprising a lithium aluminum alloy and an electrolyte material which is a mixture of lithium fluoride, lithium chloride and lithium bromide; b. an electrolyte pellet comprising said electrolyte material and an inert immobilizer selected from the group consisting of magnesia and boron nitride; c. a cathode pellet comprising said electrolyte material and an active material selected from the group consisting of iron sulphide, iron disulphide and titanium disulphide; d. an electrically insulating, inert tube within which the above-mentioned pellets are arranged, the inert tube fitting closely around said pellets; and e. an electrical contact plate bounding the cell at one end thereof and extending beyond the inner peripheral surface of the inert tube: wherein the cells are arranged in a least one stack in which the cells are connected in series by the electrical contact plates.

Claim 22

A high temperature secondary battery comprising a plurality of cells each cell having: a. an anode pellet comprising a lithium aluminum alloy and an electrolyte material which is a mixture of lithium fluoride, lithium chloride and lithium bromide; b. an electrolyte pellet comprising said electrolyte material and an inert immobilizer selected from the group consisting of magnesia and boron nitride; c. a cathode pellet comprising said electrolyte material and an active material selected from the group consisting of iron sulphide, iron disulphide and titanium disulphide; d. an electrically insulating, inert tube within which the above-mentioned pellets are arranged, the inert tube fitting closely around said pellets; and e. an electrical contact plate bounding the cell at one end thereof and extending beyond the inner peripheral surface of the inert tube: wherein the cells are arranged in a least one stack in which the cells are connected in series by the electrical contact plates.