As EV sales boom and grids seek more energy storage, researchers are racing to develop batteries that are cheaper, more powerful, and less reliant on hard-to-source materials. Lithium-ion still dominates, but sodium-ion and solid-state technologies are moving from lab to market.
The market for batteries these days is insatiable. Demand has grown more since 2010, thanks mainly to electric cars: Sales of EVs hit 20 million in 2025, or about a quarter of all cars sold globally. Shipping containers packed with batteries are also being called into play to store the electricity from renewables like solar. Storage capacity for the grid has grown twentyfold in just five years.
This boom has fed a frenzy in battery research and development. “In the past five years, innovation went very, very fast,” says Teo Lombardo, a former battery chemist and now an analyst for the International Energy Agency. “In 2024, over 40 percent of energy-related patents were on batteries. That’s never happened before. That tells you how quickly the market is evolving, and how much interest there is.”
Lithium-ion batteries are today’s gold standard for lightweight, high-powered energy storage for laptops, power tools, smartphones, drones, and electric cars. But now, says Lombardo, two new technologies are attacking lithium-ion’s dominance from either end of the cost spectrum: Cheap but bulky sodium batteries promise to run budget electric vehicles and help to power the grid; and expensive but powerful solid-state batteries offer long ranges for luxury EVs. Meanwhile, plenty of other battery chemistries are being tested in the lab, with hopes that new winners might eventually emerge to power the future.
Lombardo says that the battery market is becoming so large that it’s not a matter of one technology replacing another, it’s about specializing to serve different parts of the market.
Sodium batteries could help fill the booming market for grid storage with batteries that have easier-to-source ingredients.
But lithium is difficult to mine — often involving evaporation ponds that spread over thousands of acres — and sourced from just a handful of spots. Combine that with booming demand, and prices can spike. An enticing alternative is sodium: It’s just one step down on the periodic table, with chemistry similar to lithium, but far more common. Swapping lithium for sodium in the battery manufacturing process is relatively straightforward. As it happens, sodium-ion batteries also work well at very cold temperatures.
The main problem with sodium is that its atoms take up more than twice the volume of lithium and weigh three times more. That’s an issue when you’re trying to make a small, light battery. For now, the energy density of sodium-ion batteries is about 30 percent less than their lithium competitors, taking that average SUV only about 220 miles. But work is ongoing to optimize these batteries’ components, chemistry, and architecture.
A few tens of thousands of sodium-ion-powered electric cars entered the market in China in 2023, and the first car slated for mass production was unveiled in February. For now, LFPs are price competitive with the sodium upstarts because of economies of scale. But analysts expect sodium to add a cheaper battery variety to the overall mix, with the possibility of domestic supply chains. “The more technologies you have, the more resilient the market will be,.
Innovations in the architecture of the battery cell have accelerated charging times — some can be charged in 10 minutes.
Making a battery is fundamentally simple: A child can create one out of a lemon, a galvanized nail, a copper penny, and a couple of wires. Chemical reactions occur between the two electrodes — the cathode and the anode — and the lemon-juice electrolyte that’s sandwiched in between them, driving electrons through the wires to light up a bulb.
But making a really good battery — one that packs a lot of power into a small package, is cheap to manufacture, survives through a decade of charging cycles without degrading or starting fires, works in the cold of winter and the heat of summer, and can be easily refurbished or recycled — is another thing entirely. Creating good batteries is such a delicate work of chemistry and engineering that it typically requires decades of research to get it right. “It’s like a symphony. Everything needs to cooperate,” says Jagjit Nanda, a materials scientist and head of the SLAC-Stanford Battery Center in Menlo Park, California.
Back in the 1970s, the oil crisis spurred investment in energy alternatives. Lithium was an obvious choice for lightweight batteries because it’s the lightest metal on the periodic table. The key innovation was designing electrodes that could safely and efficiently host lithium ions in gaps between their atomic layers, leading to the first commercial lithium-ion battery in 1991.
Since then, researchers have painstakingly improved lithium-ion batteries by changing the formulations of electrodes, adding small amounts of various elements to improve battery stability or ion flow, or tweaking the microstructure of interfaces between layers or the architecture of the cell. Since 1991, lithium-ion battery energy density (an important measure of how much charge can be packed into a given weight) has tripled, and the price has dropped up to a hundredfold. Eventually those improvements will tap out — but not yet. Today’s electric car batteries are almost all lithium-ion of one type or another, typically taking your average sport utility vehicle between 250 and 370 miles on a good day.
A decade ago, most EV batteries were nickel manganese cobalt (NMC) variants (named after the primary ingredients in their positive electrode, the cathode), which boast a relatively high energy density. Recently, though, these have been overtaken by cheaper lithium iron phosphate (LFP) batteries, named after their own cathode, which are catching up in performance and contain fewer critical metals than NMCs — expensive ingredients with limited supply chains.
Although an individual LFP battery has a lower energy density than an NMC, LFPs are more heat stable, so developers have found ways to pack them closer together in a car, counteracting this disadvantage. Other innovations in the architecture of the cell have also accelerated their charging time – some LFPs can be charged in about 10 minutes.