Battery Breakthrough Provides Five Times The Driving Range Of Lithium-Ion At A Lower Price

Scientists at the University of Michigan have made a breakthrough in lithium-sulfur technology that could lead to widespread adoption of batteries with five times the energy density of today's lithium-ion cells.

Lithium-sulfur batteries already exist, but are held back from widespread adoption by problems inherent in their design. Scientists at the University of Michigan now believe they've solved these problems with a major breakthrough in the field of Li-S battery design. Before we get into that, here's a quick overview of the component parts of a battery.

Anatomy of a Battery
There are four components in lithium-ion and lithium-sulfur batteries: cathode, anode, electrolyte, and separator. The cathode is the positive side and allows current to flow out of the battery with the anode serving as its negative counterpart. The electrolyte allows for the movement of ions between the two, and the separator keeps them from coming into contact. The lithium-sulfur battery's Achilles' heel is its cathode, though Michigan's scientists believe they may have a solution for this weakness.

Current Problems with Lithium-Sulfur
Cathodes in lithium-sulfur batteries expand and contract by 78% with each charging cycle, making them unable to compete with lithium-ion because of how much faster they degrade and fail. Before Michigan's breakthrough this meant a lifespan of just ten charging cycles; now there's talk of 1000.

Breakthrough Design
The scientists breakthrough is inspired by the natural world, specifically the membrane which serves to protect organic cells. By using recycled Kevlar, the team was able to create a network of nanofibers which supports the cathode and allows it to cope with the fluctuations it experiences without degrading. It's early days yet, but the team believe that their discovery could lead to lithium-sulfur EV batteries that will last for ten years of driving.

The good news isn't limited to larger driving ranges for the EV world either. Sulfur is the 5th most abundant element on Earth and its widespread adoption could significantly lower the price of batteries that use it in their design. Cobalt, which is used as a cathode material in current generation lithium-ion batteries, ranks 32nd on the list of our planet's most abundant elements and is found in fewer areas of the world with more than 70% of annual production coming from the Democratic Republic of the Congo. There have been numerous complaints of child and slave labor, as well as horrific safety records in these mines.

2000+ Mile EVs
If lithium-sulfur batteries do come to be widely accepted by the EV market we could see vehicles able to cover some pretty mind-blowing distances on a single charge. Take the current production EV range record holder, the 520-mile Lucid Air, for example. With five times the energy density of Li-Ion batteries giving five times the range, a Li-S equipped Air could theoretically travel 2600 miles on a single charge.

What's more, the extreme power density of lithium-sulfur batteries would allow a much smaller unit to match or surpass today's EV batteries meaning less weight, better handling, and vastly increased efficiency. The future is coming, and it might well be powered by lithium-sulfur batteries.

Images by Lucid Motors and Pixabay licensed by CC BY 2.0.

James Walker is an automotive journalist at Torque News focusing on Lucid Motors. If it's got wheels he's interested in it, and he's very excited to see what kind of cars the EV revolution brings us. Whether it's fast, slow, new, or old, James wants to have a look around it and share it in print and on video, ideally with some twisty roads involved. You can connect with James on Twitter, Instagram, and LinkedIn.