Long Hours of Droning On

Dean Sigler Batteries, Electric Powerplants, Fuel Cells, Hydrogen Fuel, Solar Power, Sustainable Aviation 0 Comments

Several different organizations are trying different ways to keep unmanned aerial vehicles, UAVs, up longer.  We’ll look at three recent efforts in long-endurance missions, each with a unique technological approach. Wirth Research – Hydrogen Fuel Cell Wirth Research is now constructing a new tilt rotor, Vertical Take Off and Landing (VTOL), hydrogen fuel cell powered, advanced terrain-mapping drone.  Carrying a payload of sensors and onboard data processing capabilities, the vehicle will be powered by a complete H2 storage, control and power system provided by HES of Singapore, a specialist in ultra-light hydrogen fuel cells. The Wirth machine’s missions range from precision agriculture, to pipeline and cable inspection for utilities, surveillance and other security-related tasks, through to detection and monitoring support …

Even with Batteries, Paul MacCready Was Right

Dean Sigler Batteries, Sustainable Aviation 0 Comments

Dr. Paul MacCready repeatedly urged us to do more with less, getting big results from modest use of materials.  That philosophy may be upheld yet once again by researchers from the Helmholtz-Zentrum Berlin (HZB) Institute of Soft Matter and Functional Materials. As reported here many times, people like Dr. Yi Cui at Stanford University, researchers at MIT, the Fraunhoffer Institute in Germany and many others are attempting to find the magic combination of ingredients that will allow us to transcend the weight penalty we currently trade for payload in heavier-than-desired electric aircraft. Scientists at the HZB, led by  by Prof. Matthias Ballauff have directly observed for the first time a lithium-silicon half-cell during its charging and discharge cycles.  Dr. Beatrix-Kamelia …

Solid State Electrolyte – a Safer, More Powerful Alternative

Dean Sigler Electric Powerplants, Sustainable Aviation 0 Comments

Making batteries smaller, lighter, and more powerful is an ongoing trend, supposedly climbing at eight percent per year in terms of energy density (energy stored per unit of weight).  Even this blog is guilty of sometimes unrequited enthusiasm for some new developments that appear to be an “answer” for aircraft use. Getting a battery that double or quintuples energy density would be ideal for aircraft, but seems to be a labor worthy of Sisyphus (you could look it up).  As constantly noted here, batteries have three major components, the anode, or negative electrode; the cathode, or positive electrode; and the electrolyte, usually a liquid that allows the flow of ions between electrodes.  That electrolyte is subject to overheating and on …

Aluminum Yolks and Titanium Shells

Dean Sigler Electric Powerplants, Sustainable Aviation 0 Comments

A new “yolk-and-shell” nanoparticle could boost the capacity and power of lithium-ion batteries. MIT’s press release gives a graphic overview of what damages electrodes and shortens battery life.  “One big problem faced by electrodes in rechargeable batteries, as they go through repeated cycles of charging and discharging, is that they must expand and shrink during each cycle — sometimes doubling in volume, and then shrinking back. This can lead to repeated shedding and reformation of its “skin” layer that consumes lithium irreversibly, degrading the battery’s performance over time.” Dr. Yi Cui and teams at  Stanford’s National Accelerator Laboratory (Formerly the Stanford Linear Accelerator Center), and the Environmental Molecular Sciences Laboratory (EMSL) at Pacific Northwest National Laboratory all published papers on a similar  joint …

Cambridge Crude Reborn in Simplified Battery

Dean Sigler Electric Powerplants, Sustainable Aviation 0 Comments

We first saw the appellation, “24M” four years ago in our report on research done at MIT to produce an ionic liquid called “Cambridge Crude,” usable in flow batteries.   Dr. Yet-Ming Chiang headed up that work in collaboration with Professors Angela Belcher and Paula Hammond at MIT and Glenn Amatucci at Rutgers, among others.  They formed a commercial spinoff and seemingly went underground for the next four years. Dr. Chiang and his associates had previously gone commercial with A123, which went through the trial of bankruptcy and being acquired by overseas investors.  It’s now solvent and looking to double output.  24M is a spin-off of A123. We found that Professor Chiang had resurfaced when friend and blog reader Marshall Houston …

The Magnificent Seven Ride Again

Dean Sigler Electric Powerplants, Sustainable Aviation 0 Comments

SolidEnergy is an MIT spin-off with a lithium battery that’s been touted by R&D Magazine as “potentially…the biggest breakthrough in battery technology since Sony introduced the first Li-ion battery in 1991.”  Unlike other manufacturers with indefinite product dates, SolidEnergy says it will release a 2 Amp-hour smartphone and wearable battery in 2016 and a 20 Ah electric vehicle battery in 2017. SolidEnergy claims their Solid Polymer Ionic Liquid (SPIL) electrolyte enables creation of an “ultra-thin lithium metal anode, and improves the cell-level energy density by 50 percent compared to graphite anodes and 30 percent compared to silicon-composite anodes.”  The electrolyte adds non-flammability and non-volatility, operating safely at temperatures up to 300° C. We reported on this company last year when …

100 Percent Efficiency? Great! and So What?

Dean Sigler Electric Powerplants, Sustainable Aviation 0 Comments

A particularly brilliant and demanding manager for whom your editor used to work had a “SO WHAT?” stamp with which he would critique our technical papers and proposals.  His point in defacing our papers was not to be snide, but to force us to defend why we included certain facts – interesting though they may be in themselves. Two different and equally brilliant discoveries by University of Cambridge and University of California, Riverside researchers bring the “so what?” stamp to mind.  Even with their breakthroughs, approaching 100-percent efficient solar cells in the first instance, solar cells may not yet be a perfect fit for aircraft propulsion. Each square foot of the earth’s surface receives about 15 Watts of solar energy …

Trapping Light: A “Perfect” Solar Absorber?

Dean Sigler Electric Powerplants, Sustainable Aviation 0 Comments

The news item from David L. Chandler at the Massachusetts Institute of Technology (MIT) claims that researchers there have come close to realizing the “ideal” for solar absorption, trapping and containing all of light’s wavelengths that reach earth’s surface from the sun.  This absorbed sunlight is converted to heat by a two-dimensional metallic dialectric photonic crystal, which can absorb sunlight from a wide range of angles and withstand extremely high temperatures.  Even better, it can be made cheaply and in large quantities, according to MIT. One aspect of the design that might make it difficult to use on aircraft is its high operating temperature.  A solar-thermophotovoltaic (STVP) device, the energy from the sunlight hitting the cells is “first converted to …

Cheap Hydrogen, Anyone?

Dean Sigler Electric Powerplants, Sustainable Aviation 0 Comments

Researchers in Glasgow and at Stanford University have devised ways to decouple oxygen and hydrogen from water without resort to expensive extraction or storage techniques.  Both breakthroughs involve low-cost materials, low-energy requirements, and the production of clean hydrogen through what should be renewable energy resources. The latter overcomes one major objection to hydrogen production.  As Professor Lee Cronin of the University of Glasgow’s School of Chemistry explains, “Around 95% of the world’s hydrogen supply is currently obtained from fossil fuels, a finite resource which we know harms the environment and speeds climate change. Some of this hydrogen is used to make ammonia fertilizer and as such, fossil hydrogen helps feed more than half of the world’s population. “The potential for …

Batteries, Fuel Cells – or Something Else?

Dean Sigler Electric Powerplants, GFC, Sustainable Aviation 0 Comments

We’re coming to a parting of the ways in energy storage development for electric cars.  Or we may be coming to a joining of technologies in new and previously unimagined ways.  One side, led by Elon Musk and his Tesla Empire, promotes battery power and development.  Yet, in Tesla’s home state of California, government and private investments in hydrogen vehicles is growing.   Several Asian and European automakers are bringing out fuel cell powered vehicles in the face of low numbers of existing fueling stations.  For all the promotion from either side, future “green” cars may become too expensive for private ownership, and various approaches to providing personal mobility may replace the traditional owner-driver model.  Regardless of the outcomes or market …