Stereolithography Three-Dimensional Printing Solid Polymer Electrolytes for All-Solid-State Lithium Metal Batteries

Abstract

Liquid-free all-solid-state lithium metal batteries (ASSLMBs) are promising candidates to meet the requirements of safety and high energy density for energy storages. However, poor interfacial contact is a major obstacle limiting their applications. Herein, we report a solid polymer electrolyte (SPE), originally prepared by stereolithography (SLA) three-dimensional (3D) printing for ASSLMBs. A 3D-Archimedean spiral structured SPE is rationally designed, which can shorten the Li-ion transport pathway from the electrolyte into the electrode, reinforce the interfacial adhesion, and improve the mass loading of active materials. The SLA printed SPE exhibits a high ionic conductivity of 3.7 × 10 −4 S cm −1 at 25 °C. Furthermore, Li|3D-SPE|LFP cells achieve reduced interfacial impedance and higher specific capacity of 128 mAh g −1 after 250 cycles than those using structure-free SPE of 32 mAh g −1 . This work opens the great promise of SLA 3D printing technology to fabricate high-performance SPEs in ASSLMBs for next-generation energy storages.

Recent advancements in solid electrolytes integrated into all-solid-state 2D and 3D lithium-ion microbatteries

“…Thus, careful selection is crucial. As a cathode material in 3D all-solidstate LIMBs compounds such as LCO, [70][71][72] spinel structures, such as LiNi 0.5 Mn 1.5 O 4 (LNMO), [73][74][75] LiFePO 4 (LFP), 76,77 vanadium oxides, 31,78 and others have been utilized. Currently, extensively studied LCO with relatively high capacity, stability, and mature manufacturing procedure prevails as a cathode material, while other promising materials are under development.…”

“…4d). 77 The electrolyte had high ionic conductivity (3.7 Â 10 À4 S cm À1 ) at room temperature, and cells achieved a higher capacity of 128 mA h g À1 aer 250 cycles at 0.1C and stable cycling compared to 2D microbattery (32 mA h g À1 ), 77 hence, proving that this technology is a promising candidate for microbattery fabrication.…”

“…110 The effect of other electrodeposition conditions needs to be studied more. Parameters of other new methods such as sol-gel, 63 photolithography, 82 stereolithography, 77 ink-jetting, 14 UV-induced photopolymerization, 91 and their inuence on SPE characteristics have not been investigated in detail yet and require more attention in the future.…”

“…71 He et al reported the cells with 3D spiral solid polymer electrolyte, the superior performance of which was caused not only by shortened Li-ion pathways between electrode and electrolyte but also due to reinforced interfacial adhesion and ability of 3D structures to maintain more mass loading of active materials. 77 Edström et al stated that the large surface area of the anode and cathode provides improved capacity per footprint area and high power capabilities if the 3D cell offers a short transport distance between the electrodes and thin layers of the electrode materials on the current collectors. Thus, the capacity can be increased by a factor of 10-30 per footprint area by using the appropriate 3D design.…”

“…77,[302][303][304][305][306] One successful investigation was done on 3D spiral SPE deposited by stereolithography, where the 3D structure tested in the coin cell had stable and better cycle performance compared to the 2D structure, proving that this technology is a promising candidate for SPE fabrication. 77 This relatively simple printing method, where complex inks preparation and postprocessing of printed parts are not needed, has great potential and requires further adoption for the microbattery. 77 Most probably, as a result of low viscosity requirements for the materials printing process, only a few articles are available on SPE 3D printing up to now.…”