Indigo carmine (IC) is a cheap, renewable and water-soluble redox-active dye material that can also reversibly accommodate Li ions in the solid state. With the aim to promote efficient and processable organic batteries, this work reports the fabrication and the electrochemical performance of composite electrodes made of indigo carmine formulated with carbon black and carboxymethylcellulose. The composite electrode is obtained via an original aqueous processing wherein IC is solubilized in the electrode ink and crystallized into micrometric particles during the drying of the electrode tape. Formulation optimization allowed to lower the additive carbon content down to 10% wt. The resulting low-carbon organic cathode presents good electrochemical performance vs. Li in the 1.6-3.2 V potential window and LP30 electrolyte, with 110 mAh.g(-1) initial discharge capacity and 86% retention over 50 cycles at C/10 rate. The rate capability is also attractive with a capacity of 75 mAh.g(-1) at 2C. This works highlights the opportunity of organic battery electrodes to be more competitive toward inorganic electrodes thanks to developments focused on the formulation optimizations. (c) 2019 The Electrochemical Society.