3D printable solid and quasi‐solid electrolytes for advanced batteries

Abstract

Compared with traditional lithium‐ion systems, solid‐state batteries could achieve significantly higher energy density and improved safety. The design and method of synthesis of solid electrolytes are known to affect the electrochemical performance and mechanical integrity of a battery upon charge/discharge. 3D printing, while being the most advanced method for the fabrication of solid electrolytes, remains a bottleneck in the all‐printed batteries and, hitherto, has not been systematically investigated. In this mini‐review, an attempt has been made to address the issue of 3D printing of ceramic and polymer electrolytes by utilizing different approaches, in order to compare the conductivity of printed electrolytes and the electrolytes prepared by standard methods, and to propose investigation and development directions in this rapidly growing field.

3D Printing Nanostructured Solid Polymer Electrolytes with High Modulus and Conductivity

“…[ 10 ] Despite this, direct 3D printing of high‐performance electrolyte materials without extensive post‐processing requirements remains a bottleneck in the development of all‐3D‐printed energy‐storage devices. [ 13 ] While there are examples of swelled and crosslinked PEO based polymer electrolytes produced via additive manufacturing, [ 12,14 ] these amorphous quasi‐solid electrolytes are typically soft and flexible and lack defined nanostructuration. There are currently no examples of directly 3D‐printed functional SPEs that are rigid solids.…”

Materials for 3D Printed Metal and Metal‐Ion Batteries

“…FDM has also been used to print electrolytes. In this case, the most common strategy is the infiltration of pre‐printed PLA‐based membranes with liquid electrolytes forming quasi‐solid electrolytes (QSEs) [24] . However, there are also true solid‐state electrolytes printed by FDM based on solid polymeric electrolytes (SPEs).…”

“…Although these seem to be the long‐term future of printed batteries, there is still a myriad of problems that plague the practical integration of those strategies, such as low ionic conductivities and hard electrode/electrolyte interfaces [157] . Therefore at the moment, there is a more common hybrid approach that consists of the gelation or containment of liquid electrolytes in solid or semi‐solid matrixes [24] . This is the case of the quasi‐solid‐state or gel electrolytes.…”

“…where similarly used AJP to deposit and infiltrate the SPE on the cathode to later crosslink it with UV light [38] . Reversely, their stability with Li metal and its inhomogeneous plating is still lacking and that is why are not so common the use of SPEs with Li‐metal [24,164] . Still, this type of solid electrolytes, especially the PEO‐based, are the most common choice for fully solid printed batteries due to their easy processability and the good interfaces achievable.…”

What Would Battery Manufacturing Look Like on the Moon and Mars?

“…A FDM printer is fed with a thermoplastic filament that is extruded by heating it above its melting temperature. Composite filaments loaded with battery active materials have been prepared and printed as battery components (electrodes, ,− electrolyte, − separator, , and current collectors). The addition of an adequate plasticizer into the filament is critical to allow the introduction of a high loading of active material and conductive additives .…”