Resource World Magazine

F E B R U A R Y / M A R C H 2 0 2 0 www.resourceworld.com 91 Park Pennsylvania, led by Chao Yang Wang think they might have developed a new battery technology that could poten- tially recharge an electric car to 80% in just 10 minutes. Wang said, "We demon- strated that we can charge an electrical vehicle in 10 minutes for a 200 to 300-mile range. And we can do this maintaining 2,500 charging cycles, or the equivalent of half a million miles of travel." Lithium-ion batteries degrade when rapidly charged at ambient temperatures under 50 degrees Fahrenheit because, rather than the lithium ions smoothly being inserted into the carbon anodes, the lithium deposits in spikes on the anode surface. This lithium plating reduces cell capacity, but also can cause electri- cal spikes and unsafe battery conditions. Batteries heated above the lithium plating threshold, whether by external or internal heating, will not exhibit lithium plating. Researchers discovered that by heating the battery to a high temperature first, they could make it too hot for the lithium plates to form. They then tested it out on a commercially available industrial bat- tery where first they tested the battery without heating, where after 60 cycles, lithium plates began to form. They then tested the battery again where at 60 cycles, they managed to recharge the battery 2,500 times without lithium plates form- ing. The researchers are now hoping to go even further by reducing charging time to as low as 5 minutes. The US Department of Energy supported this work. VAPORIZING TRASH WITHOUT WASTE EMISSIONS Sierra Energy is a privately owned waste- to-energy gasification company. According to their website, the company focuses on converting non-recyclable trash into energy. They have developed what they call FastOx® gasifiers to create energy- dense synthesis gas (syngas), a fuel gas mixture consisting primarily of hydrogen, carbon monoxide, and often some carbon dioxide. In FastOx gasification, monitoring the amount of carbon entering the gasifier is essential as it dictates the amount of oxy- gen and steam necessary to optimize the energy production. Without a sufficient source of carbon, the system will struggle to operate at an optimal level. All other waste properties, such as mois- ture content and size, affect the efficiency of the overall system but are controlled using preprocessing systems. Almost any waste is acceptable, for example, municipal solid waste, biomass, automotive shred- der residue, railroad ties, medical waste, hazardous waste, tires, construction and demolition waste, and industrial waste. The only type of waste not recommend for processing is radioactive waste. Feedstock with a high moisture content will consume large amounts of energy as the water evaporates. To avoid this loss in efficiency, the system is designed to dry waste to approximately 20% moisture content before sending it into the gasifier. Even though the system runs optimally with dryer feedstocks, high moisture con- tent only causes a minor loss in efficiency in a FastOx system, but high moisture content creates serious technical issues in other systems. The syngas can be converted into a number of valuable end products by using back-end systems and technologies devel- oped by trusted third party companies. These true technologies can clean the syn- gas, force further chemical reactions, or run electrical generator sets. Example end products are: electricity, clean diesel fuel, hydrogen, and ammonia. n Sierra Energy is focused on the development of FastOx® gasification, a technology that turns trash into energy without burning. The company is testing new applications for gasification at the Sierra Energy Research Park in Davis, California. Source: Sierra Energy.

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