Integrated solid-state film lithium battery

The several materials required for fabrication of thin-film solid-state rechargeable lithium batteries were deposited and characterized: A glassy lithium-phosphorus oxynitride electrolyte (LiPON) between a lithium (Li) anode and crystalline lithium-cobalt oxide cathode (LiCoO2), deposited by RF-sputtering. Ti/Pt layers, deposited by e-beam were used in contacts and a silicon nitride film (Si3N4), deposited by low temperature hot-wire CVD protects the battery. This technology allows batteries with a potential of 4.5 V, typical capacities of 50 μAcm−2 and chargedischarge rates up to 4C. Solid-state film batteries show faster charge rates and very high cycle life, compared with film polymer batteries, withstanding several thousands of cycles with no pronounced fading.
Portuguese Foundation for Science and Technology, project FCOMP-01-0124-FEDER-007226 (with the previous reference PTDC/EEA-ENE/66855/2006) and FCOMP- 01-0124-FEDER-010909 (with the previous reference FCT/PTDC/SAU-BEB/100392/2008).