Laser powder bed fusion of pure Sn thin walls towards 3D current collectors for Zn-based batteries

Although zinc-based secondary batteries represent a promising alternative to lithium-ion systems, their practical implementation is still limited by cyclability and durability issues, mainly associated with the Zn anode. Additive Manufacturing (AM) offers geometrical flexibility and engineered porosity to tackle these challenges, particularly for the anode and current collector (CC). For the latter, tin has proven to be an appealing material, capable of improving performance by inhibiting degradation phenomena while ensuring safety and low cost. However, the literature shows no evidence of application of this material in powder bed fusion with laser beam for metals (PBF-LB/M) processes. In this work, pure Sn processability is investigated for the first time, starting from Remelting test on tin foil to define preliminary process window in terms of laser power and scan speed, then Single Track Exposure strategy is applied to deposit thin-walled geometries. Results demonstrate that high densification ('99.5%) can be achieved at P=100 W within the investigated parameter range, confirming the feasibility of processing pure Sn by PBF-LB/M for thin-walled structures.