Battery

1. A battery comprising

a housing defining an electrochemical zone,

at least one electrode that comprises a conductive substrate, wherein the substrate comprises a first region in the electrochemical zone and a second region that protrudes from the electrochemical zone, and

a metal contact tab that is coupled to the second region, wherein the ratio of the width of the second region to the width of the contact tab is from 2:1 to 3:1;

wherein the contact tab provides electrical connection with the electrode; wherein current flows in and out of the electrode through the contact tab during charge, during discharge, or both during charge and discharge of the battery, and wherein the contact tab conducts heat away from the conductive substrate;

wherein the conductive substrate is a metal sheet that is a sheet of metal foil;

and wherein the battery comprises at least one electrode that is an anode comprising a conductive substrate that is in the form of a sheet of lithium metal or lithium metal alloy.

2. A battery as claimed in claim 1 , wherein the width of the second region is less than or equal to the width of the first region.

3. A battery as claimed in claim 1 , wherein the contact tab is formed from nickel foil, and the nickel foil is coupled to the sheet of lithium foil by a weld.

4. A battery as claimed in claim 1 , wherein the cell comprises at least one cathode that comprises a current collector in the form of a sheet of aluminium foil, whereby a cathode active material is deposited onto at least part of the first region of the sheet of aluminium foil.

5. A battery as claimed in claim 4 , wherein the cathode active material comprises a matrix comprising an electroactive sulphur material and an electrically conductive material.

6. A battery as claimed in claim 4 , wherein the contact tab formed of aluminium foil and the aluminium foil of the contact tab is coupled to the aluminium foil of the cathode by a weld.

7. A battery as claimed in claim 1 ,

wherein the at least one electrode comprises a first anode and a second anode, wherein the conductive substrate comprises a metal sheet; wherein the first region is contained within the electrochemical zone and the second region protrudes beyond the electrochemical zone.

8. A battery as claimed in claim 1 ,

wherein the at least one electrode comprises a first cathode and a second cathode, wherein the conductive substrate comprises a current collector; wherein the first region is contained within the electrochemical zone and the second region protrudes beyond the electrochemical zone.

9. A battery as claimed in claim 1 , wherein the housing has a sealed region, whereby the second region of the conductive substrate protrudes from the electrochemical zone into the sealed region, and whereby the contact tab is coupled to and overlaps with the second region of the metal sheet in the sealed region.

10. A battery as claimed in claim 1 , wherein the housing a flexible pouch.

11. A method of removing heat from an electrochemical cell, said method comprising

providing an electrochemical battery comprising a housing defining an electrochemical zone, at least one electrode that comprises a conductive substrate, wherein the conductive substrate comprises a first region in the electrochemical zone and a second region that protrudes from the electrochemical zone, and

coupling a metal contact tab to the second region, wherein the ratio of the width of the second region to the width of the contact tab is from 2:1 to 3:1;

wherein the contact tab provides electrical connection with the electrode; wherein current flows in and out of the electrode through the contact tab during charge, during discharge, or both during charge and discharge of the battery, and wherein the contact tab conducts heat away from the conductive substrate;

wherein the conductive substrate is a metal sheet that is a sheet of metal foil;

and wherein the battery comprises at least one electrode that is an anode comprising a conductive substrate that is in the form of a sheet of lithium metal or lithium metal alloy.