ADVANCED MATERIALS & PROCESSES | JANUARY/FEBRUARY 2024 9 between styrene-butadiene rubber (SBR) and natural rubber (NR), as well as to explore how the shape and size of ZnO particles influence the dynamic behavior of SBR composites. The researchers conducted dynamic micro x-ray CT scans on these materials, rotating them during imaging while simultaneously subjecting them to vibrations from the shaker. They then developed histograms of local strain amplitudes by utilizing the local strains extracted from the 3D reconstructed images of the materials’ internal structures. These histograms, in conjunction with the materials’ loss factor, were analyzed to understand their dynamic behavior. The researchers say their new technology could enable the development of fuel-efficient rubber tires or gloves that don’t deteriorate and could even pave the way for the development of artificial organs. www.waseda.jp/top/en. THERMAL RUNAWAY IN LITHIUM BATTERIES Using an imaging technique called operando x-ray microtomography, scientists at California’s Lawrence Berkeley National Laboratory and UC Berkeley demonstrated that the presence of large local currents inside batteries at rest after fast charging could be one of the causes behind thermal runaway. “We are the first to capture realtime 3D images that measure changes in the state of charge at the particle level inside a lithium-ion battery after it’s been charged,” says researcher Nitash P. Balsara. The team is also the first to measure ionic currents at the particle level inside the battery electrode. Experiments show that when graphite is fully lithiated, it expands a tiny bit, about a 10% change in volume—and that current in the battery at the particle level could be determined by tracking the local lithiation in the electrode. The research team found that after charging the battery in 10 minutes, the local currents in a battery at rest were surprisingly large. The 3D microtomography instrument at Berkeley Lab’s Advanced Light Source enabled the researchers to pinpoint which particles inside the battery were the outliers generating alarming current densities as high as 25 milliamps per centimeter squared. The researchers also learned that the measured internal currents decreased substantially in about 20 minutes. Much more work is needed before their approach can be used to develop improved safety protocols. lbl.gov. In rare cases a er fast charging, a resting lithiumion battery can experience thermal runaway. Upcoming Events AeroMat March 12–14 Charlotte, NC Heat Treat Mexico April 9–11 Queretaro, Mexico ITSC April 29–May 1 Milan, Italy SMST May 6–10 Cascais, Portugal North American Cold Spray Conference September 10–11 Boucherville, Canada IMAT September 30–October 3 Cleveland, OH 2024 For more information visit: asminternational.org/events 29th IFHTSE World Congress October 1–3 Cleveland, OH 10th International Conference on Advances in Materials, Manufacturing & Repair for Power Plants October 15–18 Bonita Springs, FL ISTFA October 28–November 1 San Diego, CA
RkJQdWJsaXNoZXIy MTYyMzk3NQ==