Fig. 4.

Conductive paper as the current collector for Li-ion batteries. (A) Schematic illustration of the conductive paper battery configuration. The metal leads contact only CNTs but not active materials. Lithium foil is used as the counter electrode in half-cell tests. (B) Galvanostatic charging/discharging curves of LiMn₂O₄ nanorod cathode (3.5–4.3 V) and Li₄Ti₅O₁₂ nanopowder anode (1.3–1.7 V) half-cells with conductive paper current collectors. The current rate is C/5. (C) Cycling performance of LiMn₂O₄ nanorod (C/3, 49 mA/g) and Li₄Ti₅O₁₂ nanopowder (C/3, 58 mA/g) half-cells. (D) A 5 cm² paper battery (a full cell with LiMn₂O₄ nanorod cathode, C/Si core/shell NW anode, and conductive paper current collectors) used to repeatedly light up a blue LED.