University of Texas at Austin researchers are tackling two of the bigger challenges facing electric vehicles: limited range and slow recharging.

The researchers fabricated a new type of electrode for lithium-ion batteries that could unleash greater power and faster charging. They did this by creating thicker electrodes – the positively and negatively charged parts of the battery that deliver power to a device – using magnets to create a unique alignment that sidesteps common problems associated with sizing up these critical components.

Graphic image depicting a battery built using magnetic field orientation of electrode components. Image Credit: University of Texas at Austin. Click the press release link for the largest view.

The result is an electrode that could potentially facilitate twice the range on a single charge for an electric vehicle, compared with a battery using an existing commercial electrode.

Guihua Yu, a professor in UT Austin’s Walker Department of Mechanical Engineering and Texas Materials Institute explained, “Two-dimensional materials are commonly believed as a promising candidate for high-rate energy storage applications because it only needs to be several nanometers thick for rapid charge transport. However, for thick-electrode-design-based next-generation, high-energy batteries, the restacking of nanosheets as building blocks can cause significant bottlenecks in charge transport, leading to difficulty in achieving both high energy and fast charging.”

The key to the discovery, published in the Proceedings of the National Academy of Sciences, uses thin two-dimensional materials as the building blocks of the electrode, stacking them to create thickness and then using a magnetic field to manipulate their orientations. The research team used commercially available magnets during the fabrication process to arrange the two-dimensional materials in a vertical alignment, creating a fast lane for ions to travel through the electrode.

Typically, thicker electrodes force the ions to travel longer distances to move through the battery, which leads to slower charging time. The typical horizontal alignment of the layers of material that make up the electrode force the ions to snake back and forth.

Zhengyu Ju, a graduate student in Yu’s research group who is leading this project said, “Our electrode shows superior electrochemical performance partially due to the high mechanical strength, high electrical conductivity, and facilitated lithium-ion transport thanks to the unique architecture we designed.”

In addition to comparing their electrode with a commercial electrode, they also fabricated a horizontally arranged electrode using the same materials for experimental control purposes. They were able to recharge the vertical thick electrode to 50% energy level in 30 minutes, compared with 2 hours and 30 minutes with the horizontal electrode.

The researchers emphasized they are early in their work in this area. They looked at just a single type of battery electrode in this research.

The team’s goal is to generalize their methodology of vertically organized electrode layers to apply it to different types of electrodes using other materials. This could help the technique become more widely adopted in industry, so it could enable future fast-charging yet high-energy batteries that power electric vehicles.

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While the publicity momentum is about EVs now there is a huge market out there right now for electronic devices that could easily use an upgrade.

That said, these are fascinating research results! The depth of understanding about how to optimize batteries is expanding at an impressive rate. There is surely some of this progress going to consumer benefits. Although the steady increase in lithium cost might hide the benefits, faster recharges and more capacity for the same raw material input could well mean less lithium use per comparable battery capacities.

The hint is that the lab test electrode could be halved. Lets hope that makes it to commercial scale!

There is also a long list of team members: The research team includes, from The University of Texas at Austin: Yu, Ju, Xiao Xu, Xiao Zhang and Kasun U. Raigama; and from Stony Brook/Brookhaven National Laboratory: Steven T. King, Kenneth J. Takeuchi, Amy C. Marschilok, Lei Wang and Esther S. Takeuchi.

The research was funded by the U.S. Department of Energy through the multi-institutional Energy Frontier Research Center, the Center for Mesoscale Transport Properties.


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