10 Sept 2023
Researchers have recently discovered a way to make an efficient battery out of zinc — an inexpensive, commonly found metal — instead of the rare metals used in lithium batteries.
Most rechargeable batteries today are lithium-ion batteries, which include other metals like cobalt and nickel, Tech Xplore reports. As electric vehicles (EVs) and large-scale energy storage get more common, we’ll need more and more of those metals — but because they’re uncommon, the costs are often massive.
Many researchers are working on cheaper battery options to reduce or replace these metals. One Chinese company has created a car powered by a sodium battery, and a University of Maryland researcher has invented a partly biodegradable battery made of zinc and crab shells. Researchers have even found not one but two ways to store energy in ordinary sand.
According to Tech Xplore, this new project, led by Xiulei “David” Ji of Oregon State University, offers yet another alternative to lithium-ion batteries: accessible, efficient zinc metal batteries.
The secret is a new electrolyte developed by Ji and his team, Tech Xplore explains. A battery electrolyte is a liquid inside the battery that helps aid the chemical reactions to store and release energy.
Unfortunately, past electrolytes in zinc batteries were not very efficient. Much of the energy stored in the battery was previously used up in extra, unwanted chemical reactions. Not only did that mean the battery couldn’t release as much energy as it had put into it, but it also generated dangerous hydrogen gas. This meant that zinc wasn’t practical for rechargeable batteries.
Ji’s team has created a new electrolyte formula that almost eliminates these unwanted reactions, Tech Xplore reports. It forms a protective coating on the zinc component of the battery that prevents that type of energy loss. A similar protective coating is what allows lithium-ion batteries to release more than 99% of the charging energy. The new zinc battery releases 99.95% of the energy it is charged with on each cycle.
Not only is the zinc battery efficient, but it’s also safer than a lithium-ion battery, according to Tech Xplore. The new electrolyte isn’t flammable, while the ones used in lithium-ion batteries often are combustible. Both zinc and the components of the electrolyte are also cheaper and more common than the materials used in lithium-ion batteries.
“The breakthrough represents a significant advancement toward making zinc metal batteries more accessible to consumers,” Ji told OSU News and Research Communications. “These batteries are essential for the installation of additional solar and wind farms. In addition, they offer a secure and efficient solution for home energy storage, as well as energy storage modules for communities that are vulnerable to natural disasters.”