Researchers at Edith Cowan University (ECU) in Australia have found that batteries built from zinc and air could be a better alternative than lithium-ion batteries to power electric vehicles. The team redesigned and tested zinc-air batteries using a combination of cheaper, safer, and sustainably sourced materials, which allowed for improved lifespan and performance.
Lithium-ion batteries have become a popular choice for electric vehicles around the world due to their ability to store large amounts of energy in a small package. However, these batteries face several limitations related to cost, finite resources, and safety concerns.
With the emergence of next-generation long-range vehicles and electric aircraft in the market, there’s a growing demand for better battery systems that can offer higher performance, greater safety, and more cost-effectiveness compared to the current lithium-ion batteries.
“Rechargeable zinc-air batteries (ZABs) are becoming more appealing because of their low cost, environmental friendliness, high theoretical energy density, and inherent safety,” ECU’s Dr Muhammad Rizwan Azhar, who led the project, said.
A zinc-air battery consists of a zinc-negative electrode and an air-positive electrode. The chemistry behind them is promising, and they’re a more sustainable option than lithium-based counterparts. However, the technology’s power output has been limited due to the poor performance of air electrodes, which has also led to a shorter lifespan.
The Edith Cowan University team’s breakthrough has enabled engineers to redesign zinc-air batteries using a combination of new materials, such as carbon, cheaper iron, and cobalt-based minerals. Researchers proposed a composite electrode with a unique architecture and synergistic effect for ZABs by coupling the CoNiFe-layered double hydroxides (LDH) with cobalt coordinated and N-doped porous carbon (Co-N-C) network, resulting in excellent bi-functionality and durability.
When the bi-functional air electrode was integrated into ZABs, it displayed a high peak power density of 228 mW cm−2 and a low voltage gap of 0.77 V over an ultra-long lifespan of 950 hours, making it highly promising for practical use.
“The new design has been so efficient it suppressed the internal resistance of batteries, and their voltage was close to the theoretical voltage, which resulted in a high peak power density and ultra-long stability,” Dr Azhar said in the press release.
“In addition to revolutionizing the energy storage industry, this breakthrough contributes significantly to building a sustainable society, reducing our reliance on fossil fuels, and mitigating environmental impacts. By using natural resources, such as zinc from Australia and air, this further enhances the cost-effectiveness and viability of these innovative zinc-air batteries for the future.”