AN ELECTRODE COMPOSITION FOR A SECONDARY BATTERY CELL

The present invention relates to a composite electrode material for a rechargeable battery; to a method of making a composite electrode material; to an electrode comprising the composite electrode material, especially an anode; to cells including electrodes or anodes including the composite electrode material; and to devices including said cells. In particular, there is provided a composite electrode material for a rechargeable battery cell comprising: a. an electroactive material; and b. a polymeric binder including pendant carboxyl groups characterised in that (i) the electroactive material comprises one or more components selected from the group comprising an electroactive metal, an electroactive semi-metal, an electroactive ceramic material, an electroactive metalloid, an electroactive semi-conductor, an electroactive alloy of a metal, an electroactive alloy of a semi metal and an electroactive compound of a metal or a semi-metal, (ii) the polymeric binder has a molecular weight in the range 300,000 to 3,000,000 and (iii) 50 to 90% of the carboxyl groups of the polymeric binder are in the form of a metal ion carboxylate salt.