Multiprocess 3D printing of sodium-ion batteries via vat photopolymerization and direct ink writing

Abstract

In this work, the ability to print shape-conformable batteries with multi-process additive manufacturing is reported. Vat photopolymerization (VPP) 3D printing process is employed to manufacture gel polymer electrolytes (GPEs) for sodium-ion batteries (SIBs), while direct ink writing process is used to prepare positive electrodes. The sodium-ion chemistry has proven to be an adequate substitute to lithium-ion due to the availability of resources and their potential lower production cost and enhanced safety. Three-dimensional printing technologies have the potential to revolutionize the production of shape-conformable batteries with intricate geometries that have been demonstrated to increase the specific surface area of the electrode and ion diffusion, thus leading to improved power performances. This study shows the preparation of composite UV-photocurable resins with different polymer matrix-to-liquid electrolyte ratios, designed to act as GPEs once printed via VPP. The impact of the liquid electrolyte ratio within the GPEs is thoroughly examined through a variety of electrochemical techniques. The exposure time printing parameter is optimized to ensure adequate print accuracy of the GPE. Using the optimized resin composition as material feedstock, shape-conformable 3D printed GPE exhibiting an ionic conductivity of 3.3 × 10−3 S·cm−1 at room temperature and a stability window up to 4.8 V vs. Na0/Na+ is obtained. In parallel, a composite ink loaded with Na0.44MnO2 and conductive additives is developed to 3D print via direct ink writing positive electrodes. After demonstrating the functionality of the independent 3D printed components in SIBs, the last part of this work is focused on combining the 3D printed Na0.44MnO2 electrode and the 3D printed GPE into the same battery cell to pave the way towards the manufacturing of a complete 3D printed battery thanks to different additive manufacturing processes.

Manipulating ionic conductivity through chemical modifications in solid-state electrolytes prepared with binderless laser powder bed fusion processing

“…Full battery pouch cells based on this gel electrolyte were mechanically robust and retained 97% of their capacity after 1000 cycles. Martinez et al combined two different additive manufacturing techniques to print Na-ion batteries with NaMnO 2 as the active material [11]. The authors demonstrated a viable half-cell battery using vat photopolymerization to prepare the electrolyte and direct ink writing to prepare the cathode.…”

Additive manufacturing of LiCoO2 electrodes via vat photopolymerization for lithium ion batteries

“…[11][12][13][14][15][16] Among the various additive manufacturing processes, material extrusion using either thermoplastic filaments 11,12,[17][18][19][20] or inks [21][22][23][24] as material feedstock for the 3D printer have been previously studied to manufacture battery components. On the other hand, vat photopolymerization (VPP), another additive manufacturing subcategory, is particularly promising for energy storage applications as this process can provide resolution ranging from as high as 100 mm down to a Department of Mechanical Engineering, The University of Texas at El Paso, El as low as 100 nm, 25,26 but has often been disregarded for the printing of the electrodes. VPP is a layer-by-layer curing approach that solidifies a liquid UV-photosensitive resin composed of a mixture of polymers and photoinitiators.…”