Environmentally friendly battery developed for low-income countries
Researchers at Linkoping University in Sweden have developed a zinc and lignin battery that can be used more than 8,000 times. This innovation aims to provide an affordable and sustainable battery solution for countries with limited access to electricity. The study was published in the journal Energy and Environmental Materials.
“Solar panels have become relatively cheap, and many people in low-income countries have adopted them. However, near the equator, the sun sets around 6 p.m., leaving households and businesses without electricity. The hope is that this battery technology, even with lower performance than the expensive Li-ion batteries, will eventually provide a solution to these situations,” says Reverant Crispin, professor of organic electronics at Linkoping University.
Crispin’s research group, together with researchers from Karlstad University and Chalmers, developed the battery using zinc and lignin. It has a similar energy density to lead-acid batteries, but avoids the use of toxic lead.
The battery remains stable for more than 8000 cycles and retains approximately 80% of its performance. It can hold a charge for about a week, significantly longer than other zinc-based batteries.
Zinc-based batteries are mainly available as non-rechargeable products. The research shows that they could ultimately complement and even replace lithium-ion batteries if rechargeability is effectively integrated.
“While lithium-ion batteries are useful when handled properly, they can be explosive, difficult to recycle and problematic in terms of environmental and human rights issues when specific elements such as cobalt are extracted. Therefore, our sustainable battery offers a promising alternative where energy density is not crucial,” says Ziyauddin Khan, researcher at the Laboratory of Organic Electronics at LiU.
One of the main challenges with zinc batteries is their poor durability, due to zinc reacting with the water in the battery electrolyte solution. This reaction produces hydrogen gas and causes dendritic growth, rendering the battery useless.
The research team used a potassium polyacrylate-based water-in-polymer salt electrolyte (WiPSE) to stabilize the zinc. This substance improves the stability of the battery in combination with zinc and lignin.
“Both zinc and lignin are super cheap and the battery is easily recyclable. And when you calculate the cost per usage cycle, it becomes an extremely cheap battery compared to lithium-ion batteries,” says Ziyauddin Khan.
Currently, the lab-developed batteries are small, but the researchers believe they can produce larger versions, similar in size to car batteries, given the abundance of lignin and zinc. However, mass production would require the involvement of a company.
Reverant Crispin highlights Sweden’s innovative role in promoting sustainable alternatives worldwide.
“We can see it as our duty to help low-income countries avoid making the same mistakes we did. When they build their infrastructure, they should start with green technology right away. If unsustainable technology is introduced, it will be used by billions of people. of people, leading to a climate catastrophe,” says Reverant Crispin.
Research report:Water-in-polymer salt electrolyte for long life rechargeable aqueous zinc-lignin battery