Lithium cobalt oxide (LCO) was proposed by Goodenough’s group in 1980 and has been widely used since its commercialization by Sony in 1991. It is the preferred option for small portable devices due to its easy synthesis, high ion/electron conductivity, high compaction density and good cycling stability, etc.¹ However, the more and more powerful devices require further improvement of the energy density, and the performance of the LCO-based batteries.² 
In recent years, thick electrode design is being intensively explored as an effective method for improving the volumetric energy density by reducing the inactive materials (e.g., current collector and separator) in LIBs. In this regard, melt processing is a very interesting processing technique as it is fast and easily scalable. Moreover, it does not use toxic solvents such as N-methylpyrrolidone avoiding safety issues and costs derived from drying and recovering steps.³  
Our group proposed a Li-ion battery based on thick additive-free ceramic negative and positive electrodes, Li₄Ti₅O₁₂ (LTO) and LiFePO₄ (LFP), respectively.⁴ This cell, with electrodes of ∼100 mg cm^-2 and ∼500 µm obtained by powder extrusion molding (PEM), delivered 13 mAh cm^-2, which is 5 times more than what is obtained by conventional electrodes of ∼100 µm. Nevertheless, its operation was restricted to slow charging/discharging rates due to the impeded ionic conductivity along the electrode thickness. The ionic conductivity is indirectly proportional to the tortuosity of the electrode,⁵ as a proper interconnection between pores has to be kept for a fast ionic diffusion and, a fair power density.
In the current work, the preparation of LCO thick (∼500 µm thick) additive-free ceramic electrodes obtained by PEM has been optimized to reach the desired physicochemical and morphological features for its application in Li-ion batteries.  First, the optimal parameters for binder elimination were established by analyzing the effectiveness of the process under several treatment durations and atmospheres.
Afterward, a thorough study of the sintering step was carried out. The effect of sintering temperature on the densification, composition, microstructure, and electrical properties was evaluated. Furthermore, the use of inert or air atmospheres was studied, detecting the formation of undesired secondary products under certain conditions.
Selected electrodes with more prone properties for their implementation as cathodes were tested in Li-ion systems displaying capacity values over 20 mAh cm^-2 with great cycling stability.
Therefore, this work describes a methodology to obtain electrodes with values of porosity, conductivity, and capacity compatible with their use in high-energy-density lithium-ion batteries.
References
1.  Wang, Y. et al. Energy and Fuels 35, 1918–1932 (2021).
2.  Wu, Q. et al.  J. Energy Chem. 74, 283–308 (2022).
3.  Verdier, N. et al. Polymers. 13, 1–26 (2021).
4.  Sotomayor, M. E. et al. J. Power Sources 437, 226923 (2019).
5.  Bae, C.-J. et al. Adv. Mater. 25, 1254–1258 (2013).