Doubling Down on Ions

Dean Sigler Batteries, Sustainable Aviation Leave a Comment

Dual-ion intercalation alloying process probably won’t roll musically off the tongue, but the process has made a test cell that has greater specific density and energy density than the batteries in Teslas. Or the Chinese BYD electric sedan, according to its makers. It’s “environmentally friendly” and low cost, to add to its sales appeal. Yongbin Tang and his colleagues at Shenzhen Institutes of Advanced Technology of the Chinese Academy of Sciences (CAS) have created an aluminum-graphite dual-ion battery (AGDIB) that, “Compared with conventional LIBs, …shows an advantage in production cost (~ 50% lower), specific density (~1.3-2.0 times), and energy density (~1.6-2.8 times).” The team claims their battery can reach a volume energy density of the AGDIB ~560 Wh/L, “considerably higher” than Tesla’s Model S  Panasonic batteries (~350 Wh/L) or the BYD E6’s LiFePO4 lithium iron phosphate cells (~200 Wh/L).  The team further claims their battery outperforms electrochemical capacitors. After 200 charge-discharge cycles, the battery has a reversible capacity of ~100 …

MSCs Could be AOK

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Of late, your editor has noticed several press releases concerning scientific findings that don’t read in a scientific way.  You know that objective kind of writing: the use of words and phrases such as “tend to,” “suggesting,” or “of potential interest,” and the ever-popular, “further study is required.”  An announcement from the Center for Integrated Nanostructure Physics at the Institute for Basic Science (IBS) and Department of Energy Science at Sungkyunkwan University in South Korea tells a hopeful story of a new discovery mimicking nature and “displaying electrical properties about five orders of magnitude higher than similar lithium batteries, and even claiming, “stunning test results.”   These sound more like PR than simple declarative statements. Before running to your broker to see if an IPO is imminent, let’s determine what those “similar lithium batteries” are and what electrical properties are being compared. The abstract for the team’s paper in the May 6 edition of Advanced Energy Materials is more circumspect. “Inspired by natural …

Fast-Charging Batteries with a “Holey” Electrode

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Replacing the graphite used in conventional battery electrodes with “a network of tin-oxide nanoparticles” could reduce battery charging time from hours to minutes.  An energy storage device combining the advantages of batteries and capacitors is a long-term goal for researchers, and a multi-national discovery may help expedite that goal. Graphite anodes and cathodes, as used in most lithium batteries today, limit storage capacities to 372 milliampere hours per gram (mA·h/g), the theoretical maximum of graphite. By comparison, an Energizer Ultimate Lithium AA battery holds about 3,000 mAh and weighs 14.5 grams (or about 207 mA h/g). A typical rechargeable AA battery holds only 750 to 900 mAh (around 54 to 64 mA h/g).  This limit “hinders significant advances in battery technology,” according to Vilas Pol, Associate Professor of Chemical Engineering at Purdue University. There, Pol, postdoctoral research associate Vinodkumar Etacheri, and other researchers internationally have experimented with a “porous interconnected” tin-oxide-based anode, giving twice the theoretical charging capacity of graphite.  Not …

ORNL Makes It Two for Two

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Oak Ridge National Laboratory has announced that their researchers have built and demonstrated a high-voltage (5 V) lithium, solid-state battery with a usable life of more than 10,000 cycles, at the end which test the battery retains more that 90-percent of its original capacity.  That makes two such claims in a week, with ORNL’s battery comparable to that developed by Nanyang Technology University (NTU) and reported on in this blog last week. ORNL points out that, “For a given size of battery, the energy stored in a battery is proportional to its voltage. Conventional lithium-ion batteries use organic liquid electrolytes that have a maximum operating voltage of 4.3 V. Operating a battery above this limit causes short cycle life and serious safety concerns.” “In this latest study, the Oak Ridge team replaced the conventional liquid electrolyte with a ceramic solid electrolyte of lithium phosphorus oxynitride (Lipon), and used a LiNi0.5Mn1.5O4 cathode and Li anode at a charge voltage to 5.1V.” The …