This common vegetable could help make electric vehicle batteries cheaper and longer-lasting

Scientists have found that an unlikely new ingredient could help improve the lithium batteries used in electric vehicles and renewable energy systems – corn.

They have discovered that a protein found in corn can dramatically boost the performance of lithium-sulphur batteries, a next-generation alternative to today’s lithium-ion batteries that power everything from electric vehicles to smartphones.

Lithium-sulphur batteries have long been seen as a promising option for future tech, since they are lighter, cheaper and more environment friendly than the batteries we use today.

The biggest challenge in bringing them to use is that these batteries don’t last very long.

But researchers at Washington State University have shown that a protective barrier made using corn protein could extend the battery’s life by hundreds of charge cycles and potentially help get them into real-world products such as electric cars or solar power systems.

“This work demonstrated a simple and efficient approach to preparing a functional separator for enhancing the battery’s performance,” said Katie Zhong, professor of mechanical and materials engineering at the university and an author of the study. “The results are excellent.”

The corn protein works by targeting two of the biggest technical problems that have held lithium-sulphur batteries back.

In a lithium-sulphur battery, energy is stored using sulphur, a cheap, non-toxic material. But during charging, some of this sulphur can drift into the liquid centre and react with the lithium side, causing the battery to wear out much faster than a conventional one.

The lithium itself can grow tiny metal spikes known as dendrites, which can puncture the barrier inside the battery and lead to short circuits.

To solve these problems, the researchers added a thin coating of corn protein, called zein, to the separator, the layer that sits between the battery’s two sides. The coating formed a barrier which they found kept sulphur from leaking across and helped prevent dendrites from forming.

Because proteins naturally fold in on themselves, the researchers added a small amount of flexible plastic to open up the structure. This enabled amino acids in the protein – its most reactive parts – to interact more directly with the rest of the battery.

Having put that structure in place, the researchers built a small test battery that kept its charge through more than 500 cycles – far longer than lithium-sulphur designs typically manage.

Their study, published in the Journal of Power Sources, backed the results with lab experiments and simulation models, showing improvements in both stability and performance.

“Corn protein would make for a good battery material because it’s abundant, natural, and sustainable,” said Dr Jin Liu, professor in the School of Mechanical and Materials Engineering and a corresponding author on the paper.

The team is now looking into which parts of the protein structure contribute most to performance. Zein is made up of amino acids, and identifying the ones responsible for blocking sulphur migration and preventing dendrite formation could help improve the design even further.

“The first thing we need to think about is how to open the protein, so we can use those interactions and manipulate the protein,” Dr Liu said.

“A protein is a very complicated structure,” said Dr Zhong. “We need to do further simulation studies to identify which amino acids in the protein structure can work best for solving the critical shuttle effect and dendrite problems.”

The research is still in the early stage, but if lithium-sulfur batteries can be made reliable enough for real-world use, they could replace lithium-ion batteries in many key sectors – particularly electric vehicles and large-scale renewable energy storage.

So far, the approach has only been tested in coin-sized batteries, but the team hopes to collaborate with industry partners to evaluate whether the breakthrough can be scaled up.

Global demand for lithium-ion batteries is expected to soar over the next decade. In 2023 alone, battery deployment in the power sector increased by more than 130 per cent.

Lithium-sulphur batteries could be a more affordable and perhaps a comparatively cleaner alternative to the lithium-ion technology used in most electric vehicles and consumer electronics today.

Lithium-ion batteries rely on metals like cobalt and nickel, which are extracted through environmentally damaging mining under harsh labour conditions.

While sulphur is a byproduct of oil and gas refining, it makes use of an existing waste stream rather than requiring new extraction.

Sulphur is also lighter than the metal oxides used in conventional battery cathodes, so lithium-sulphur designs also come with the promise of higher energy density, which means lighter batteries that can store more power, an advantage for electric vehicles, aircraft and even grid-scale renewable storage.

And with both sulphur and corn protein widely available, the technology could also cut production costs, making it more accessible as demand for clean energy storage grows.