A Dendrite Eraser?

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

The Pacific Northwest National Laboratory in Richland, Washington, seems to have an industrious group of researchers who come up with ever-improved forms of batteries.  One of their creations, a hybrid graphite/lithium anode, was featured in this blog last year. Now, Frances White reports from the PNNL that one of the researchers involved with that work has led another team to an innovative approach to a new electrolyte for lithium batteries.  According to Ms. White, “PNNL physicist Jason Zhang (Ji-Guang “Jason” Zhang) and his colleagues have developed a new electrolyte that allows lithium-sulfur, lithium-metal and lithium-air batteries to operate at 99 percent efficiency, while having a high current density and without growing dendrites that short-circuit rechargeable batteries.” This is a real breakthrough because, for lithium batteries overall, the chemistries that give higher performance are generally more volatile.  This new material avoids those issues and gives top performance with great safety. Earlier electrolytes reacted with the lithium electrode to grow little spikes that …

Hybrid Batteries in Hybrid Vehicles?

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Frances White of the Pacific Northwest National Laboratory (PNNL) reports that a new anode quadruples the life of a test lithium-sulfur battery and could lead to much lower costs for electric vehicles and large-scale energy storage. This blog has noted that many researchers focus on development of better cathodes, or anodes, or electrolytes exclusively, neglecting a more holistic, or whole battery approach to their delving.  PNNL scientists have a reason for focusing on anodes, having found that a “battery with a dissolved cathode can still work.” What dissolves the electrodes in a battery?  “Unwanted side reactions,” according to PNNL, cause the battery’s sulfur-containing cathode to disintegrate slowly and form polysulfide molecules that dissolve into the battery’s electrolyte liquid.  This becomes a thin film that forms on the surface of the lithium-containing anode, and grows until the battery will no longer operate. Rather than trying to stop sulfur leakage from the cathode as others have, PNNL added a protective graphite shield …

Algae to Crude While You Wait

Dean Sigler Diesel Powerplants, Electric Powerplants, Sustainable Aviation 1 Comment

Engineers at the Department of Energy’s Pacific Northwest National Laboratory in Richland, Washington have beat nature by millions of years in turning algal glop into crude oil,  cooking a “a verdant green paste with the consistency of pea soup” into oil, water, and a nutritious batch of byproducts. Douglas Elliott, the laboratory fellow leading PNNL team’s research says, “It’s a bit like using a pressure cooker, only the pressures and temperatures we use are much higher.  In a sense, we are duplicating the process in the Earth that converted algae into oil over the course of millions of years. We’re just doing it much, much faster.” “Faster” means an hour or less, researchers having combined several chemical steps normally associated with bio-fuel production into one continuous process.  Wet materials in this process reduce costly and time-consuming steps normally required to dry the algae.  This simplification, among other steps, makes the process commercially viable. Elliot notes that, “Cost is the big roadblock …