Tag: EV batteries

Upcycling arsenic waste from mines could help fuel the green tech revolution

Upcycling arsenic waste from mines could help fuel the green tech revolution

Researchers from UBC, Geological Survey of Denmark develop way to convert element from toxic form to metallic arsenic, an in-demand material for solar panels and EV batteries

Arsenic waste at closed mines is one of Canada’s largest and most expensive environmental liabilities, driven in large part by historic gold mining. At the Giant Mine site in Yellowknife, NWT, 237,000 tonnes of arsenic trioxide dust is stored underground – a volume that would fill seven 10-story buildings or 9,480 dump trucks. The estimated cost for remediating the site is a whopping $4.4 billion CAD.

Canada isn’t alone in dealing with this potential threat to the environment and human health: Legacy arsenic mine waste is a global problem facing many other countries including Australia, France, and the US.Video: Upcycling arsenic waste

However, this liability is increasingly being viewed as a potential asset, with an altered form of the element – metallic arsenic – now classified as a critical mineral by several countries because of its importance for green technologies ranging from solar panels to EV batteries. Little surprise then that research teams from around the world are actively looking for ways to transform the material. 

As part of an international collaboration, environmental engineers Tamara Etmannski from the University of British Columbia and Case van Genuchten at the Geological Survey of Denmark and Greenland have developed a method for converting arsenic from its carcinogenic form into the sought-after form that could play a key role in society’s transition away from fossil fuels.

Read more on the CLS website

Go Farther, Charge Faster: Crack-Resistant Silicon Anodes

Go Farther, Charge Faster: Crack-Resistant Silicon Anodes

Developed a crack-resistant silicon anode material to reliably achieve high energy density and fast-charging performance for EV batteries.

Summary

A joint research team from POSTECH, Seoul National University, and LG Energy Solution has proposed a new design strategy to overcome the fracture problem of silicon anodes, a promising next-generation material for electric vehicle (EV) batteries. The study was recently published in the online edition of Nature Communications. Although silicon can store significantly more energy than conventional graphite, its practical application has been limited by severe volume expansion and contraction during charge–discharge cycles, which causes particle fracture. To address this challenge, the researchers incorporated crystalline lithium fluoride (LiF) into the silicon anode, simultaneously enhancing its strength and Young’s modulus. This approach significantly improved both mechanical durability and fast-charging performance. The study represents a major step toward the commercialization of high-energy-density EV batteries by satisfying two critical requirements at the same time.

Background

The performance of electric vehicle (EV) batteries is largely determined by two factors: how far a vehicle can travel on a single charge and how quickly the battery can be recharged. Conventional graphite anodes are highly stable, but their energy storage capacity is approaching its theoretical limit. Silicon, by contrast, can store nearly ten times more energy than graphite, making it one of the most promising next-generation anode materials. However, silicon undergoes significant expansion and contraction during charging and discharging. Repeated volume changes cause the particles to fracture and the electrode structure to deteriorate, ultimately shortening battery life. Previous studies have primarily focused on increasing the material’s Young’s modulus to reduce deformation. In contrast, relatively little attention has been paid to improving its strength, which is essential for preventing fracture and maintaining structural integrity under repeated volume changes.

Methodology

The research team developed a strategy to form crystalline lithium fluoride (LiF) within silicon monoxide (SiO)-based anode particles. They first introduced lithium into the particles and then infused fluorine, allowing it to react with the lithium to generate crystalline LiF inside the particles. Based on the Hall–Petch relationship1, the researchers optimized the size of the LiF crystallites to maximize particle strength while simultaneously increasing the material’s Young’s modulus. They also formed a surface protective layer that facilitated the transport of both lithium ions and electrons. The particle structure and electrochemical performance were subsequently characterized using electron microscopy, X-ray analysis at the 4C beamline of PLS-II, and electrochemical measurements.

Read more on the PAL website