The at least one cathode active material preferably comprises a material capable of occluding and releasing lithium ions selected from lithiated transition metal phosphates and lithium ion intercalating metal oxides.

Examples of lithiated transition metal phosphates are LiFePO₄, LiMnPO₄, LiNiPO₄ and LiCoPO₄, examples of lithium ion intercalating metal oxides are LiCoO₂, LiNiO₂, LiMnO₂, mixed lithium transition metal oxides containing Mn and at least one second transition metal; and lithium intercalating mixed oxides containing Ni, Al and at least one second transition metal mixed oxides.

Examples of mixed lithium transition metal oxides containing Mn and at least one second transition metal are mixed lithium transition metal oxides with layer structure having the general formula Li_1+e(Ni_aCo_bMn_cM_d)_1?eO₂

wherein

a is in the range of from 0.05 to 0.9, preferred in the range of 0.1 to 0.8,

b is in the range of from zero to 0.35,

c is in the range of from 0.1 to 0.9, preferred in the range of 0.2 to 0.8,

d is in the range of from zero to 0.2,

e is in the range of from zero to 0.3, preferred in the range of > zero to 0.3, more preferred in the range of 0.05 to 0.3,

with a+b+c+d=1, and