Solid electrolytes conduct lithium ions at room temperature and can potentially replace conventional organic electrolytes, which are flammable and toxic. In addition to drastically improving the safety of the battery, solid state electrolytes allow the use of lithium metal as the anode. This in turn increases the cell voltage and thereby increases the energy density of the battery. Sulfide compounds with high Li-ion conductivity are not commonly available, and as such, the development of solid state electrolyte–based Li-ion batteries has been plagued by the lack of widespread availability of these difficult-to-produce materials. NEI has utilized its extensive background in the synthesis of advanced materials to develop a process for producing sulfide materials in a form that potentially allows them to be used in Li-ion cells.
NEI offers its patent-pending, solid electrolyte material – lithium tin phosphorous sulfide (Li10SnP2S12) – along with various custom produced oxide and non-oxide solid electrolyte material compositions (e.g., sulfide-based), as well as a polymer-ceramic composite electrolyte and a PEO-based polymer solid electrolyte.
Sulfide-based Solid Electrolytes
Sulfide-based solid electrolytes are one of the most highly sought and promising candidates for all-solid-state batteries. NEI is actively involved in producing different compositions of sulfide-based solid electrolyte materials, including our own patent-pending LSPS.
NEI’s Lithium Tin Phosphorous Sulfide (Li10SnP2S12) powder is a “superionic” solid that conducts lithium-ions at room temperature. The solid electrolyte is designed to eliminate flammability issues associated with currently used liquid electrolytes, while providing high Li-ion conductivity (10-4 to 10-2 S/cm @ RT).
NANOMYTE® SSE-20 is a solvent-based dispersion fluid designed to be compatible with NANOMYTE® SSE-10 LSPS powder (and other sulfide-based solid electrolyte powders). The material is specially formulated to not react with LSPS and contains proprietary additives with an organic lithium salt, which acts as an ionically conductive binder.
NEI is actively involved in producing various other sulfide-based solid electrolyte compositions.
Polymer-based Solid Electrolytes
NEI provides solid polymer electrolytes for rechargeable solid-state lithium batteries. The electrolytes are based on specially synthesized polymers that are complexed with highly conductive lithium salts.
NEI’s newest solid electrolyte, SE-50, is a hybrid, polymer-ceramic composite material with high Li+ ionic conductivity and excellent electrochemical stability. It can be used as a separator, or it can be added to the electrodes. The material has been engineered such that it provides for low interfacial resistance between the electrodes and electrolyte.
This PEO-based, copolymer solid electrolyte is specifically designed for lithium-ion battery applications. H-polymer is a 100% solid amorphous material and combines the benefits of high room temperature ionic conductivity with the good mechanical properties of a solid polymer.
Other Solid Electrolytes
NEI is actively involved in producing different solid electrolyte materials of both oxide and sulfide-based compositions, as well as polymer-based solid electrolytes. A long trusted source for custom developed materials used in lithium-ion batteries, NEI is well positioned to reproducibly synthesize small and large quantities of custom solid electrolyte compositions.