Graphite anode with thick honeycomb architecture and high areal capacity fabricated via FDM 3D printing for lithium-ion batteries

Graphite as the most widely used commercial anode material, has been developed to approach the theoretical upper limit of specific capacity, which possibly unsatisfied market demand in the coming future. To pursuit higher energy density Li-ion batteries (LIBs), a way of increasing anode thickness to improve areal capacity is proposed. 3D printing as an emerging technology, has more potential than traditional slurry-casting method in manufacturing the thick electrodes. Hence, this work employs Fused deposition modeling (FDM) printing and carbonization process to fabricate a thick electrode without current collector, 3D-G, which has honeycomb architecture, high areal mass loading and high areal capacity. With the biggest thickness, 3D-G can present a 16.96 mg cm -2 areal mass loading. The architecture offers surface channel to facilitate electrolyte infiltration and Li-ion diffusion that alleviates the kinetics defect caused by scaling up thickness. With a 0.6 mm electrode thickness and 0.5 mm honeycomb thickness, 3D-G delivered a 1.69 mAh cm -2 remaining capacity and a 2.53 mAh cm -2 average capacity after 100 cycles at a 0.3 mA cm -2 . This research reveals the defects of graphite thick electrode and contributes a surface channel strategy to fabricate thick electrodes and optimize the rate and cycle capability.