High mass loading additive-free LiFePO4 cathodes with 500 μm thickness for high areal capacity Li-ion batteries

We report the preparation of thick ceramic electrodes of the olivine LiFePO4 (LFP) with high mass loading. These electrodes are preparated by means of Powder Extrusion Moulding (PEM), which is a technology easily scalable and cheap. These LFP cathodes are additive-free (neither binder nor extra carbon black) with ~0.5 mm thickness, allowing to develop very high areal capacity (13.7 mA h cm−2). By means of a strict control of sintering process, the carbon coating of the commercial LFP powder remains and the decomposition of the active material is prevented. The optimized self-supported LFP cathode presents good cyclability over 20 cycles at C/10 with no capacity loss. The good electrochemical performance of these novel LFP thick electrodes and their non-flammability make them interesting candidates for both mobile and stationary applications.