Silicon anode binder

A terpolymer [polymer (P)] consisting of:

• (A1) recurring units derived from an α,β-ethylenically unsaturated carboxylic acid monomer [monomer (AA)] of formula (III)
• wherein Ra, Rb and Rc, equal to or different from each other, are independently selected from a hydrogen atom and a C1-C3 hydrocarbon group;
• (A2) recurring units derived from a (meth) acrylamide monomer [monomer (AM)] of formula (I):
• wherein
• R1 and R2, being the same or different from each other, may be selected from a hydrogen atom, from a linear or branched alkyl group having 1 to 6 carbon atoms, a carboxylic group or an amide group,
• R3 represents a hydrogen atom or a methyl group,
• R4 and R5, being the same or different from each other, may be selected from a hydrogen atom or from a linear or branched alkyl group having 1 to 6 carbon atoms;
• and
• (B) recurring units derived from a monomer (M), different from monomer (AA) and from monomer (AM), said monomer (M) having the formula (II) below:
• wherein:
• Ri is selected from the group consisting of H,—COOH,—CH2COOH, and an alkyl group;
• wherein the alkyl group is preferably a methyl group;
• Rii and Riii, being the same or different from each other, may be selected from a hydrogen atom or from a linear or branched alkyl group having 1 to 6 carbon atoms, or can be—COOH group;
• A is a linkage selected from the group consisting of a —C(O)—O-group and a —C(O)-NH-group;
• Rx is selected from a hydrogen atom or a linear or branched C3-C20 hydrocarbon chain moiety comprising at least one functional groups selected from the group consisting of ether (—O—), heterocyclic group, sulfonic acid group (—SO3H), phosphonic acid group (-PO3H2) and phosphoric acid group (—OPO3H2).