Fabrication of micro lithium-ion battery with 3D anode and 3D cathode by using polymer wall

► Micro lithium-ion battery with 3D anode and 3D cathode was fabricated. ► The prepared cell showed 270 μA h cm−2 as the discharge capacity at 2 C rate. ► More than 60% of the discharge capacity at 2 C rate was retained at 20 C rate.