Phys.org September 26, 2023 Dual-band electrochromism, the independent modulation of visible and near-infrared light by a single material, is highly desirable for smart windows to enhance the energy efficiency of buildings. Tungsten oxides are commercially important electrochromic materials, exhibiting reversible visible and near-infrared absorption when electrochemically reduced in an electrolyte containing small cations or protons. The presence of structural water in tungsten oxides has been associated with faster electrochromic switching speeds. A team of researchers in the US (North Carolina State University, UT Austin, Vanderbilt University) found that WO3·H2O, a crystalline hydrate, exhibited dual-band electrochromism unlike the anhydrous WO3. Making […]
Tag Archives: Electrolytes
Researchers design next-generation electrolytes for lithium batteries
Nanowerk October 29, 2022 The lithium-metal batteries cycling encounters a low Coulombic efficiency (CE) due to the unceasing electrolyte decomposition. Improving the stability of solid electrolyte interphase (SEI) suppresses the decomposition and increases CE. However, SEI morphology and chemistry alone cannot account for CE, and a full explanation is still lacking. Researchers in Japan found that in diverse electrolytes, the large shift in the Li electrode potential and its association with the Li+ coordination structure influences the CE. Machine learning regression analysis and vibrational spectroscopy revealed that the formation of ion pairs is essential for upshifting the Li electrode potential, […]
Longer lasting sodium-ion batteries on the horizon
Science Daily July 13, 2022 The severe instability of the solid–electrolyte interphase (SEI) formed during repeated cycling in sodium ion batteries (NIBs) hinders their development. In particular, the SEI dissolution in NIBs with a high-voltage cathode is more severe than in the case of Li-ion batteries (LIBs) and leads to continuous side reactions, electrolyte depletion and irreversible capacity loss, making NIBs less stable than LIBs. A team of researchers in the US (Pacific Northwest National Laboratory, University of Washington) developed a rational electrolyte design to suppress the SEI dissolution and enhance NIB performance. Their electrolyte lowered the solvation ability for […]
These energy-packed batteries work well in extreme cold and heat
EurekAlert July 4, 2022 Researchers at UC San Diego have developed an electrolyte that is not only versatile and robust throughout a wide temperature range, but also compatible with a high energy anode and cathode. It is made of a liquid solution of dibutyl ether mixed with a lithium salt, and compatible with a lithium-sulfur battery. The electrolyte helps improve both the cathode side and anode side while providing high conductivity and interfacial stability. They engineered the sulfur cathode to be more stable by grafting it to a polymer. In tests, the proof-of-concept batteries retained 87.5% and 115.9% of their […]
Researchers identify alternative to lithium-based battery technology
Science Daily May 31, 2022 To make all-solid-state sodium batteries (ASSSBs) commercially viable a team of researchers in the US (University of Houston, Iowa State University, Purdue University, Rice University, Northern Illinois University, UC Irvine) has developed a family of oxysulfide glass solid electrolytes (SEs) that not only exhibit the highest critical current density among all Na-ion conducting sulfide-based SEs, but also enable high-performance ambient-temperature sodium-sulfur batteries. By forming bridging oxygen units, the solid electrolytes undergo pressure-induced sintering at room temperature, resulting in a fully homogeneous glass structure with robust mechanical properties. The self-passivating solid electrolyte interphase at the Na|SE […]