Direct-ink writing printed cathodes based on different active materials for lithium-ion batteries

Rising demand for portable electronic leads to development of energy storage systems with improved energy-/power-density. In this work, it is proposed the use of different active materials allied to Direct-Ink Writing (DIW) printing technology for the development of lithium-ion batteries cathodes. LiFePO 4 , LiMn 2 O 4 and LiCoO 2 active materials were used to produce cathodes based on Doctor Blade (DB) and DIW processing techniques to assess the influence of active filler and preparation technique on cathode's characteristics. The results demonstrate that the DIW processing technique allows to improve cathode properties also allowing the possibility of new designs and shapes necessary for portable applications. DIW induces a smooth morphology on cathode surface, lowering the presence of cracks, for the same preparation conditions as in DB. An increase of apparent lithium-ion diffusion coefficient for LiFePO 4 and LiMn 2 O 4 was observed in DIW samples, where LiFePO 4 increase from 1.71 × 10 −7 cm 2 s −1 (DB) to 3.70 × 10 −7 cm 2 s −1 (DIW). Half-cells performance demonstrated an improved or very similar discharge capacities for the samples prepared by DIW, compared to DB. LiFePO 4 cathode discharge capacities of 134.8 mAh.g −1 (DB) and 137.5 mAh.g −1 (DIW) at C/8-rate is observed. The study demonstrates the capability of DIW technique to produce customized, flexible and high-performance cathodes.