Solid-state batteries charge in a fraction of the time, run cooler, and pack more energy into less space than traditional lithium-ion versions.
A new review from the University of California, Riverside, published in Nano Energy, explains why this technology is poised to transform everything from electric cars to consumer electronics, and represents a major leap in energy storage.
Solid-state lithium battery.
These batteries replace the flammable liquid found in standard versions with a solid material that is safer and far more efficient. Where today’s batteries may take 30 to 45 minutes to reach 80% charge, solid-state models can cut that time to 12 minutes, and in some cases, as little as three.
Lead author Cengiz Ozkan, a professor of mechanical engineering at UCR, said the benefits come down to chemistry and engineering. “By removing the liquid and using stable solid materials instead, we can safely push more electricity into the battery at once, without the risks of overheating or fires,” he said.
Conventional lithium-ion batteries move lithium ions, the particles that carry electric charge, through a liquid. But that liquid can degrade over time, limit charging speed, and pose fire risks. Solid-state batteries use a solid material instead, which offers a safer and more stable environment for lithium ions to move through. This enables faster, more efficient charging with fewer safety concerns.
Conventional lithium-ion battery for a digital SLR camera
The solid inside these batteries is known as a solid-state electrolyte. The review highlights three main types: sulfide-based, oxide-based, and polymer-based. Each type has strengths: some allow ions to move faster, others offer better long-term stability or are easier to manufacture. One standout group, sulfide-based electrolytes, performs almost as well as the liquid in current batteries, but without the downsides.
The researchers also describe the tools scientists now use to watch batteries work in real time. Techniques like neutron imaging and high-powered X-rays let researchers see how lithium moves inside a battery as it charges and discharges. This helps identify areas where the lithium gets stuck or where unwanted structures called “dendrites” start to grow. Dendrites are tiny, needle-like formations that can cause a battery to short-circuit or fail.
Understanding these inner workings is key to making better batteries. “These imaging tools are like an MRI for batteries,” Ozkan said. “They let us watch the battery’s vital signs and make smarter design choices.”
Solid-state batteries also tend to use lithium more efficiently. Many designs feature a lithium metal layer that can store more energy in less space than the graphite layers used in current batteries. This means solid-state batteries can be lighter and smaller while still powering devices for just as long, or longer.
While conventional lithium-ion batteries typically begin to show noticeable degradation after approximately 5–8 years of use in electric vehicles, solid-state batteries could remain functional for 15–20 years or more, depending on usage and environmental factors.
“Traditional lithium-ion batteries, while revolutionary, are reaching their performance and safety limits as electric vehicles, renewable energy grids, portable electronics, and aerospace systems become more widespread and demanding,” Ozkan said.
Ozkan said solid-state batteries could also play a pivotal role in the future of interstellar travel and space exploration.
Due to their thermal and chemical stability, these batteries are better suited to withstand extreme temperatures and radiation conditions in outer space. They’re also able to store more power in less space, which is critical for missions where every cubic centimeter counts. And without liquid electrolytes, they would be more reliable in closed, oxygen-controlled environments like spacecraft or planetary bases.
The researchers’ goal with this review was to guide researchers and technologists in accelerating the development, scalability, and real-world deployment of solid-state systems.
But challenges remain. Making these batteries on a large scale is still difficult and expensive. The paper offers a roadmap for solving these problems, including developing better materials, refining how the battery parts interact, and improving factory techniques to make production easier.
“Solid-state batteries are moving closer to reality every day,” Ozkan said. “Our review shows how far the science has come and what steps are needed next to make these batteries available for everyday use.”
