Solid-state lithium batteries are considered the future of energy storage.
They promise to be safer and more powerful than the lithium-ion batteries we use today in phones, laptops, and electric cars. But there’s a problem: they don’t last as long.
A new study by scientists in China has found out why—and it has to do with tiny cracks and stress inside the battery’s anode, the part that stores and releases lithium during charging.
The main issue is something called metal fatigue. This is when a material becomes weaker after being stretched and squeezed many times.
In solid-state lithium batteries, the lithium in the anode expands when the battery charges and shrinks when it discharges.
Over time, this repeated movement causes small cracks and empty spaces, called microvoids, to form between the anode and the solid electrolyte, which is the part that allows lithium ions to flow through the battery.
These cracks create weak spots that allow tiny, needle-like structures called dendrites to grow. Dendrites are dangerous because they can pierce through parts of the battery and cause a short circuit, which can make the battery fail or even catch fire.
This is one of the main reasons why solid-state batteries don’t last very long.
To understand the process better, the researchers used high-powered microscopes and computer simulations to watch how the battery materials changed over time.
What they discovered is that the damage in the anode follows a known scientific rule called the Coffin-Manson law.
This law describes how materials crack and break after being repeatedly stressed. This means the problem is not random—it’s built into how the battery works, which actually gives scientists a good starting point to solve it.
The researchers believe that by understanding this predictable behavior, engineers can design new battery materials or structures that reduce the stress and prevent cracks from forming. That could stop dendrites from growing and make solid-state batteries last much longer.
This discovery could be a turning point for battery technology.
If scientists can find a way to fix the metal fatigue problem, solid-state lithium batteries might finally live up to their promise—powering our future devices and vehicles with more energy, less risk, and longer life.
