Lithium-ion batteries have powered our phones, laptops and electric vehicles for more than 30 years. They have changed the way we live, but they are far from perfect.
They are still relatively heavy, can catch fire if badly damaged, and rely on materials such as lithium, nickel and cobalt, which are expensive to mine and can create environmental and ethical concerns.
So why hasn’t a better battery replaced them yet?
According to researchers in Norway, the answer is simple: designing a new battery is much harder than it seems.
Their insights were recently shared in an article explaining the challenges facing battery research and the progress being made toward safer, cheaper and more sustainable alternatives.
Professor Ann Mari Svensson from the Norwegian University of Science and Technology (NTNU) says battery technology has actually advanced remarkably quickly.
Although lithium-ion batteries first reached the market in 1991, they were built on more than two decades of research, and scientists are still improving them today.
At NTNU, researchers build small experimental batteries from scratch in the laboratory. These coin-sized batteries allow them to test new materials without producing full-sized batteries.
One promising project is exploring batteries made with aluminum and graphite instead of lithium. Because aluminum is far more common and less expensive, it could eventually help lower battery costs.
Developing a new battery involves much more than replacing one material with another. Researchers repeatedly charge and discharge the batteries, sometimes hundreds or even thousands of times, before opening them to examine what has changed inside.
Powerful microscopes and chemical analysis help reveal why batteries lose performance over time and how different materials react with one another.
One of the biggest challenges is finding the right electrolyte, the material that allows charged particles to move between the battery’s two electrodes. Even if scientists discover an excellent new electrode material, it must also work well with a suitable electrolyte.
The final battery must be safe, lightweight, affordable, durable and capable of being manufactured on a large scale. Balancing all of these requirements is extremely difficult.
Computer simulations help researchers predict how atoms and molecules behave inside batteries, but these models cannot fully replace laboratory testing. Much of battery development still depends on years of careful experiments and trial and error.
Some alternatives are already beginning to appear. Sodium-ion batteries, which replace lithium with sodium, are one example. Sodium is abundant and inexpensive, making these batteries attractive for certain uses. Although they are slightly heavier than lithium-ion batteries, they are already being introduced in some vehicles in China.
Battery technology is also becoming more specialized. Different applications require different strengths. For example, electric ferries can often use heavier, lower-cost batteries because weight is less critical than it is in a passenger car. Norway has become a world leader in battery technology for electric ships, helping drive innovation in the maritime industry.
Researchers are also excited about solid-state batteries, which replace the liquid electrolyte with a solid material. These batteries could offer better safety and higher performance, but they are still being refined before they can be widely produced.
Another growing option is lithium iron phosphate, or LFP, batteries. They store slightly less energy than today’s common nickel-manganese-cobalt batteries but are cheaper, last longer and are generally considered safer.
Even when scientists develop a promising new battery, getting it onto the market can take around 10 years. New designs must undergo years of testing to prove they are reliable, safe and able to maintain their performance over time. Independent organizations must also verify these results before the batteries can be used in products such as electric vehicles.
Rather than one battery replacing all others, researchers expect the future to include many different battery technologies, each designed for specific jobs.
As research continues, the next generation of batteries is likely to be safer, more affordable and better suited to the growing range of devices and vehicles that depend on them.
