Abstract: Thin film LiCoO₂ electrodes were successfully prepared with a novel facile and low-cost computer ink-jet printing technique. For preparing the stable colloid “ink”, wet ball-milling was employed to stabilize the nano LiCoO₂ particles and conducting agent acetylene black(AB) while two kinds of polymeric hyper dispersants CH10B and CH12B were used, respectively. Nano LiCoO₂ particles were synthesized through the self-assembly method using triblock copolymer P123 as a template. The morphology, crystal structure and electrochemical performance of jet printing LiCoO₂ thin film electrodes were investigated in detail via SEM, XRD, cyclic voltammograms(CV) and galvanostatic charge-discharge measurements. It was determined that the average thickness of the as-printed thin-film LiCoO₂ electrode was about 1.27 m. The CV curves show that the heat treatment was benefit for improving the electrochemical properties of electrode. After a slight annealing process at 450 ℃ for 30 min, the thin film electrode presented a good reversible CV behavior. In the cycling process with constant charge-discharge current 20 A/cm² within the potential range of 3.0—4.2 V(vs. Li⁺/Li), the initial discharge capacity of thin film LiCoO₂ electrode was 81 mA·h/g, and after 50 cycles it remained 87%. After 10 cycles the charge-discharge efficiency reached near 100%.

Key words: Computer ink-jet printing, Thin-film electrode, Lithium ion battery, LiCoO₂