By submitting this form, you are agreeing to the Terms of Use and Privacy Policy.
Promising materials for use as solid electrolytes in the next-generation lithium batteries are lithium superionic conductors with the structural type Li10GeP2S12 (LGPS).
Li9.42Si1.02P2.1S9.96O2.04 (LSiPSO), a unique member of the LGPS family, and its solid solutions were created by quenching from 1273 K in the Li2S-P2S5-SiO2 pseudoternary system. The addition of oxygen to the LGPS-type structure increased the material’s ionic conductivity to 3.2 104 S cm1 at 298 K and increased its electrochemical stability to lithium metal.
With a high reversibility of 100%, an all-solid-state cell with a lithium metal anode and LSiPSO as the separator demonstrated exceptional performance. As a result, oxygen doping is a useful technique for increasing the electrochemical stability of LGPS-type structures.
The creation of alternate methods for processing air-sensitive thiophosphate-based solid electrolytes is required for the mass manufacture of solid-state batteries.
To provide a foundation for this, we examine the chemical stability and ionic conductivity of the tetra-Li7SiPS8 (LiSiPS) LGPS-type lithium-ion conductor. We explain the makeup of the vibrant polysulfides that form during solvent processing and pinpoint their formation to the dissolution of the Li3PS4-type amorphous side phase that is commonly present in LiSiPS.
We discover that LiSiPS is broken down by nucleophilic attack in water and alcohols into oxygen-substituted thiophosphates and thioethers, and we suggest a reaction mechanism for the latter. Furthermore, we demonstrate that further high-temperature treatment allows quaternary thiophosphates to recrystallize from MeOH solutions.
Quaternary thiophosphates can be processed wet using aprotic solvents with donor numbers less than 15 kcal mol-1 because they preserve the electrolyte’s crystal structure and its strong ionic conductivity of >1 mS cm-1.
By using anisole as a case study, we demonstrate that, as compared to dry solvents (5 ppm), a residual water content of up to 800 ppm does not significantly worsen the ionic conductivity.
A drop in ionic conductivity is also seen as the solvent residue is added, and this decrease is dependent on the solvent’s donor number as well as the vapour pressure and interactions between the solvent’s molecules and the thiophosphate groups in the solid electrolyte.
Therefore, improving the solvent processing techniques for thiophosphate electrolytes is a complex task. This research offers generalizable knowledge on LiSiPS resistance to organic solvents, which may facilitate cost-effective and extensive thiophosphate-based solid electrolyte manufacturing.
The Global LGPS solid electrolyte market accounted for $XX Billion in 2023 and is anticipated to reach $XX Billion by 2030, registering a CAGR of XX% from 2024 to 2030.
Harvard developed a new solid state cell using a BMT sandwich logic.
An inferior battery is produced when lithium and LGPS are brought into direct contact. LPSCI makes for a more stable battery that is susceptible to dendrites. The answer was to sandwich LGPS between two layers of LPSCI, much like bacon is sandwiched between tomato layers in a BLT.
It may seem weird, but the new “BLT” solid-state cell managed 2,000 cycles of charging at 1.5C while retaining 81.3 percent of its capacity. How is it possible for it to keep more capacity after 20,000 fast-charging cycles at 20C than it can when charging at only 1.5C?
