Rechargeable electrochemical metal ion, has great ability and whose flexibility allows great conformability

The present invention relates to a novel electrochemical battery architecture (A) metal ion, with areas devoid of rigid electrode materials themselves and preferably also devoid of separator material. These areas are flexible and thus define the accumulator fold lines which allow a high flexibility of the accumulator by elastic deformation of the flexible package, the current collectors substrates and optionally the separator and according to multiple configurations possible from a same basic geometry.