Additive manufacturing (AM) techniques using advanced functional materials are attracting strong attention in the field of all solid-state lithium batteries (ASSBs) since they are considered as innovative approaches that will pave the way for cheaper, safer, and customizable batteries with exceptional volumetric energy density. In the present work, stereolithography (SLA) is presented as a suitable technique to produce complex-shaped Li_1.5Al_0.5Ge_1.5P₃O₁₂ (LAGP) full-ceramic electrolytes from glass feedstock. Printed electrolytes showed an ionic conductivity in good agreement with LAGP fabricated by conventional techniques (σ = 6.42 × 10⁻⁵ S cm⁻²). Moreover, 3D printed LAGP corrugated membranes with interfacial area increased by 15% were fabricated showing an equivalent reduction of the area specific resistance. Symmetrical cells with lithium metal electrodes were used to study the stripping and plating behaviour of LAGP printed electrolytes coated with a germanium protective interlayer deposited via thermal evaporation. The symmetric cells showed a stable cycling performance over 250 hours demonstrating the stability of the designed cells. The innovative approach reported here represents the first step for the next generation of ASSBs based on LAGP, offering new degrees of freedom for the manufacturing of full ceramic electrolytes with a complex shape.

Mesoporous ceria possesses high potential as a functional material for high-temperature energy applications, owing to an ordered percolation network for oxygen ion conductivity, a good catalytic activity towards solid/gas reactions and a maximized porosity in the nanometric range. Here we developed highly performing gadolinium-doped mesoporous cerium oxide scaffolds for solid oxide cell oxygen electrodes by introducing chemical post-treatments into the state-of-the-art hard-template nanocasting synthesis route. The so-obtained improved mesoporous backbones were infiltrated with a mixed ionic electronic conductor (strontium- and iron-doped lanthanum cobaltite) forming a nanocomposite with excellent compatibility with the electrolyte. The resulting full solid oxide cells exhibit remarkable functional properties yielding an excellent performance in fuel cell and co-electrolysis of steam and carbon dioxide modes with a maximum power density of 1.35 W cm⁻² at 0.7 V and an injected current of 1.30 A cm⁻² at 1.3 V, respectively, at T = 750 °C. These values surpass those of the state-of-the-art benchmark cells, sparking the interest towards novel strategies based on ceramic nanocomposites for a new generation of solid oxide cells.