Microelectrodes fabricated by printing techniques. (A) Schematic illustration of the nonplanar 3D-printed electrode and (B) photographs of the nonplanar 3D-printed cathodes on 3D substrates [71]. (C) Schematic of screen-printing fabrication of printed Zn//MnO₂ microbatteries [72]. (D) Fabrication process of 2D metal patterns transformed from 3D printed stamp and (E) images of 500 μm stamp, Ni patterns on paper, and Au/Ni patterns on paper [78]. Reproduced with permission.