Researchers crack a key problem with sodium-ion batteries for electric vehicles and grid energy storage

Phys.org  September 27, 2024 Microstrain and the associated surface-to-bulk propagation of structural defects are known to be major roadblocks for developing high-energy and long-life batteries. However, the origin and effects of microstrain during the synthesis of battery materials remain largely unknown. A team of researchers in the US (Argonne National Laboratory, Brookhaven National Laboratory) performed microstrain screening during real-time and realistic synthesis of sodium layered oxide cathodes and gathered evidence from multiscale in situ synchrotron X-ray diffraction and microscopy characterization. They found that the spatial distribution of transition metals within individual precursor particles strongly governed the nanoscale phase transformation, local […]

Solid electrolyte composed of nanoparticles shows promise for all-solid-state batteries

Phys.org October 2, 2024 Halide solid electrolytes are promising for improving the electrochemical performance of all-solid-state batteries. However, the state-of-the-art sodium-ion-conducting halides are not as high in conductivity as expected and lack reduction stability. Researchers in Japan found oxychlorides in a ternary system NaCl–TaCl5–Ta2O5 have high conductivities, formabilities, and oxidation and reduction stabilities. They mechanochemically prepared samples composed of NaCl and Ta2O5 nanoparticles embedded in an Na–Ta–Cl–O amorphous matrix, possessing ionic conductivities of 2.5 × 10–3 S cm–1 at 25 °C and electrochemical potential windows of 0.4–4.1 versus Na+/Na. Compression tests revealed that the nanoparticles in the oxychloride electrolytes improved […]

Chemists create gel to prevent leaks and boost lithium-ion battery life

Phys.org  September 2, 2024 A key impediment for lithium battery technologies is the utilization of flammable organic solvent-based electrolytes which pose significant safety risks, and the recyclability of batteries has not reached the level required for transitioning to a circular economy. Researchers in Germany described poly(ionic liquid)-based dual network gel electrolytes as safer and sustainable alternative materials. The materials employed both, dynamic and covalent crosslinking, allowing the fabrication of mechanically stable gels with a high content (up to 65 wt%) of ionic liquid/salt both via thermal and photo polymerization. Mechanical stability, combined with enhanced ionic conductivity was achieved via the […]

Study of disordered rock salts leads to battery breakthrough

MIT News  August 23, 2024 Co- and Ni-free disordered rock salt cathodes utilize oxygen redox to increase the energy density of lithium-ion batteries, but it is challenging to achieve good cycle life at high voltages >4.5 V. An international team of researchers (USA – MIT, Pennsylvania State University, Argonne National Laboratory, Lawrence Berkeley National Laboratory, Brookhaven National Laboratory, South Korea, Canada, China, Taiwan) found a family of Li-excess Mn-rich cathodes that integrates rock salt- and polyanion-type structures. Following design rules for cation filling and ordering, they demonstrated the bulk incorporation of polyanion groups into the rock salt lattice. This integration bridged […]

A breakthrough in inexpensive, clean, fast-charging batteries

Science Daily  July 3, 2024 Anode-free batteries possess the optimal cell architecture due to their reduced weight, volume and cost. However, their implementation has been limited by unstable anode morphological changes and anode–liquid electrolyte interface reactions. An international team of researchers (USA – UC San Diego, University of Chicago, University of Korea) showed that an electrochemically stable solid electrolyte and the application of stack pressure could solve these issues by enabling the deposition of dense sodium metal. An aluminium current collector was found to achieve intimate solid–solid contact with the solid electrolyte, which allowed highly reversible sodium plating and stripping […]

A ‘liquid battery’ advance—strategies for electrocatalytic hydrogenation

Phys.org  June 12, 2024 The selective electrocatalytic hydrogenation of organics with transition metal hydrides is a promising strategy for electrosynthesis and energy storage. Researchers at Stanford University reported the electrocatalytic hydrogenation of acetone with a cyclopentadienone-iridium complex in a tandem electrocatalytic cycle with a cobaltocene mediator. The reductive protonation of cobaltocenium with mild acids generated (C5H5)CoI(C5H6) (CpCoI(CpH)), which functioned as an electrocatalytic hydride mediator to deliver a hydride to cationic Ir(III) without generating hydrogen. Electrocatalytic hydride transfer by CpCoI(CpH) to a cationic Ir species led to the efficient electrohydrogenation of acetone. According to the researchers hydride–transfer mediation presents a powerful […]

Nonreciprocal quantum batteries exhibit remarkable capacities and efficiency

Phys.org  June 8, 2024 Nonreciprocity enables directional flow of signals and efficient noise suppression, constituting a key element in the architecture of current quantum information and computing systems. An international team of researchers (Poland, Canada) introduced nonreciprocity through reservoir engineering during the charging process resulting in a fourfold increase in battery energy compared to conventional charger-battery systems. This effect was observed in the stationary limit and remained applicable even in overdamped coupling regimes, eliminating the need for precise temporal control over evolution parameters. The result could be extended to a chiral network of quantum nodes, serving as a multicell quantum […]

Carbon-capture batteries developed to store renewable energy, help climate

Science Daily  May 15, 2024 To investigate the deactivation and reactivation mechanisms of the aqueous Na–CO2 battery during extended cycling, researchers at Oak Ridge National Laboratory designed the cathode to include non-precious intermetallic catalysts. As the cell underwent repeated cycles, the voltage polarization during discharge progressively rose, eventually led to the cell’s deactivation and formation of decomposition products clogging the electrode surface. Results obtained from comprehensive characterization techniques provided insight into the decomposition products. They showed an electrochemical approach for regeneration of the aqueous cells. According to the researchers their findings provide a path toward creating long-duration systems with self-healing […]

Disorder improves battery life

Science Daily  May 8, 2024 On charging the Li-deficient frameworks in lithium (Li)-ion cathodes become vulnerable to lattice strain and structural and/or chemo-mechanical degradation, resulting in rapid capacity deterioration and thus short battery life. Guided by fundamental principles of structural chemistry and achieved through an improved ceramic synthesis process, an international team of researchers (the Netherlands, China) developed an approach that addressed these issues using the integration of chemical short-range disorder (CSRD) into oxide cathodes, which involved the localized distribution of elements in a crystalline lattice over spatial dimensions, spanning a few nearest-neighbour spacings. They demonstrated how the introduction of […]

Mess is best: Disordered structure of battery-like devices improves performance

Science Daily  April 18, 2024 The difficulty in characterizing the complex structures of nanoporous carbon electrodes has led to a lack of clear design principles with which to improve supercapacitors. Charge is stored within the porous carbon structure, and pore size has thus long been viewed as the key factor for determining storage capacity. An international team of researchers (UK, France) evaluated commercial nanoporous carbons and did not find a correlation between pore size and capacitance. Rather, their combination of simulations and data measurements indicated that the key factor was the extent of disorder, as smaller graphene-like domains could more […]