Sodium-aluminum battery for energy transition?
Until now, such batteries have been based almost exclusively on lithium-ion technology. A new sodium-aluminum battery concept developed by researchers at the Pacific Northwest National Laboratory (PNNL) is now expected to bring new advantages.
The new sodium-aluminum battery developed by researchers at the Pacific Northwest National Laboratory (PNNL) is not impressive for its performance or other superficially positive properties, but for the raw materials from which it is made. Both metals are abundant on Earth, unlike lithium and cobalt, which are needed for today's most common electricity storage devices. That makes them a price-taker for storing excess electricity from wind and solar power plants.
Solid state electrolyte on board
The anode of the innovative battery consists of aluminum wool and liquid salt, while the cathode is made of metallic sodium. Between them is a solid-state electrolyte that allows sodium ions to pass through, but prevents the two electrodes from coming into contact with each other and causing a short circuit.
"We have shown that this new liquid-salt battery design provides much faster charging and discharging than high-temperature sulfur-sodium batteries. They also operate at a much lower temperature and the energy storage capacity is maintained over many charge and discharge cycles," said PNNL materials scientist Guosheng Li. After 345 cycles, it was still 82.8 percent.
Clean energy megatrend
Imre Gyuk, director of the Office of Electricity, Energy Storage Program of the US Department of Energy, which supported this research, notes, "This battery technology, made with low-cost, domestically available materials, brings us one step closer to our nation's clean energy goals."
Although the battery is in its early stages and currently only button cell-sized, researchers speculate that an energy density of up to 100 watt-hours per kilogram (Wh/kg) is achievable when it is "fully grown." That of lithium-ion batteries used in commercial electronics and e-vehicles is 170 to 250 Wh/kg. Thus, the new battery is only suitable for stationary operation.
"Our main goal for this technology is to provide a low-cost, daily shift of solar energy to the grid over a ten- to 24-hour period," says PNNL battery technology expert Vince Sprenkle. Most current battery technologies, including lithium-ion batteries, are well suited for short-term energy storage, he said. Meeting power needs for more than 10 hours would require the development of new, low-cost, safe and long-lasting battery designs.
Source: Press text.com
