Phys.org October 3, 2024 A team of researchers in the US (Cornell University, Rice University, University of Chicago, Columbia University) assembled a new supramolecular porous crystal from fused macrocycle-cage molecules. The molecule comprised a prismatic cage with three macrocycles radially attached. The molecules formed a nanoporous crystal with one-dimensional nanochannels. The supramolecular porous crystal can take up lithium-ion electrolytes and achieve an ionic conductivity of up to 8.3 × 10–4 S/cm. Structural analysis and density functional theory calculations revealed that efficient Li-ion electrolyte uptake, the presence of 1D nanochannels, and weak interactions between lithium ions and the crystal enabled fast […]
Tag Archives: Lithium-ion battery
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 […]
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 […]
New design for lithium-air battery could offer much longer driving range compared with the lithium-ion battery
Science Daily February 22, 2023 Lithium-air batteries have scope to compete with gasoline in terms of energy density. However, in most systems, the reaction pathways either involve one- or two-electron transfer, leading to lithium peroxide (Li2O2) or lithium superoxide (LiO2), respectively. A team of researchers in the US (Illinois Institute of Technology, Argonne National Laboratory, Illinois University) used a composite polymer electrolyte based on Li10GeP2S12 nanoparticles embedded in a modified polyethylene oxide polymer matrix. They found that Li2O is the main product in a room temperature solid-state lithium-air battery. The battery was rechargeable for 1000 cycles with a low polarization […]
New strategy proposed for ultra-long cycle lithium-ion battery
Phys.org December 15, 2022 In the process of battery reaction, stress accumulation and lattice oxygen loss will cause some microcracks in lithium-rich manganese-based materials. The migration of transition metal ions will lead to phase transition of materials and other harmful side reactions. Researchers in China prepared high-performance cathode materials for lithium-rich manganese-based lithium-ion batteries. They did sulfur doping and in-situ growth of coherent spinel phase synchronously on the surface of lithium-rich manganese-based materials. The formation of TM-S bond configuration induced by S incorporation can effectively accelerated the lithium ions diffusion and suppressed the undesired oxygen redox. Therefore, the LMRS@S cathode […]
Flameproofing lithium-ion batteries with salt
Science Daily December 7, 2022 A team of researchers in the US (Stanford University, SLAC National Accelerator Laboratory, UC Berkeley) found that anchored solvent molecules can increase the ionic conductivity of the electrolyte without undermining its non-flammability. They developed a liquid-state polymer electrolyte composed of LiFSI salts, dimethoxyethane (DME) solvents, and polysiloxane tethered with ion-solvating moieties. DME coordinated with both the salt and the polymer, while, together with the salt, they synergistically plasticized the polymer to increase the ionic conductivity. The resulting non-flammable polymer electrolyte had a room-temperature ionic conductivity of 1.6 mS/cm and a wide operation window of 25°C–100°C. […]
New salts raise the bar for lithium ion battery technology
Phys.org August 16, 2021 Lithium battery materials, currently in use, fall short in terms of safety and performance holding back the next generation of high-performance batteries. In particular, the development of the electrolyte poses a key challenge for higher power batteries suitable for energy storage and vehicle applications. Researchers in Australia have synthesized safe fluoroborate salts with battery grade purity by recrystallisation process. When put in a lithium battery with lithium manganese oxide cathodes, the cell cycled for more than 1000 cycles, even after atmospheric exposure. The salt was found to be very stable on aluminum current collectors at higher […]
These lithium-ion batteries can’t catch fire because they harden on impact
Science Daily August 22, 2018 In a lithium-ion battery, a thin piece of plastic separates the two electrodes. If the battery is damaged and the plastic layer fails, the electrodes can come into contact and cause the battery’s liquid electrolyte to catch fire. Researchers at Oak Ridge National Laboratory used perfectly spherical, 200-nanometer-diameter particles of silica suspended in common liquid electrolytes for lithium-ion batteries. On impact, the silica clump together and block the flow of fluids and ions. Uniformly sized particles disperse homogeneously. If they are not homogenously sized, the liquid becomes less viscous on impact. If the electrodes don’t […]