Researchers introduce alternatives to lithium batteries

(CN) - As global demand increases, the mineral resources needed to make batteries can become tight, but researchers at the Georgia Institute of Technology say they may have found a viable alternative to traditional lithium battery construction.

Scientists at Georgia Tech say new research suggests that batteries made with potassium and sodium are promising – and perhaps even better than lithium – for battery storage.

The team published a study in Joule magazine on Tuesday to outline the study of potassium and sodium batteries. It says that potassium and sodium are not the preferred ions for cell manufacturing because they are more susceptible to decay than other ions such as lithium.

“But we found that this is not always the case,” said Matthew McDowell, assistant professor of the George W woodruff School of Mechanical Engineering, in a statement.

Scientists have studied the reaction of three ions - lithium, sodium and potassium - with mineral pyrite particles. They found that pyrite is more stable during the reaction with sodium and potassium, which may indicate that batteries based on sodium or potassium ions may be much longer than previously thought.

When the battery is charged and discharged, the ions react with the particles constituting the battery electrode and penetrate the particles. Studies have shown that this process causes the volume of the electrode particles to vary greatly, often breaking them down into small pieces. Since sodium and potassium ions are larger than lithium, these ions are believed to cause more degradation of the battery electrode.

Lithium-ion batteries have high power density and relatively low cost, making them the best choice for portable electronic devices, power grids, and energy storage for growing hybrid and electric vehicles.

According to the US Geological Survey, batteries account for 39% of global lithium consumption.

Scientists at the Georgia Institute of Technology observed chemical reactions using electron microscopy using potassium, lithium and sodium and iron sulfide battery electrodes. According to the study, they found that iron sulfide is more stable when reacted with sodium and potassium than in lithium.

Matthee Boebinger, a graduate student at Georgia Tech, said: "We saw a very strong response, no breaks - indicating that this and other similar materials can be used in these new batteries and have higher stability."

The battery has three main components - the cathode, the anode and the electrolyte solution. When the cathode and the anode are connected, electrons flow from the anode to the cathode, generating an electric current.

Lithium is usually present in the cathode of the battery, while the electrolyte is usually present in the form of a lithium salt. The anode material is typically carbon based, typically graphite. Lithium-ion batteries can produce twice as much power as alkaline batteries.

"Lithium batteries are still the most attractive now because they have the highest energy density. You can pack a lot of energy in this space," McDowell said. “Sodium and potassium batteries have no more density at this point, but they are based on elements that are 1000 times more abundant on Earth than lithium-lithium batteries. So they may be much cheaper in the future, for large-scale energy storage – for the family It is very important to provide backup power to the future grid."

According to the US Geological Survey, the global lithium production increased about 12% in 2016, to cope with the increased demand for battery applications.

Lithium reserves are distributed in five continents - North America, South America, Africa, Asia and Australia. South America has the highest concentration, accounting for about 66% of global lithium reserves.

There are two main ways to produce lithium: brine and hard rock. When brine is used, the mineral has been concentrated in the aqueous solution and is extractable. Hard rock supplies of pegmatite have been found throughout the world, but granite-rich pegmatites are uncommon, accounting for less than 1% of the world's pegmatite deposits.

Chile is the second largest lithium producer in the world, with lithium reserves ranking first. Its reserves are preserved in salt mines and the main deposit is the Salar de Atacama. The area covers an area of about 3,000 square kilometers and is estimated to have 6.8 million tons of lithium reserves.

Last fall, research by scientists at Stanford University showed that there may be more lithium reserves in volcanoes around North America, which may help reduce US dependence on international lithium supplies.

Although the current annual consumption of lithium is small compared to the estimated global extractable lithium reserves, Stanford University researchers say that demand for lithium may become critical by 2030. The use of lithium-ion batteries in mobile electronics and hybrid and electric vehicles requires the discovery of new lithium resources to meet growing demand and diversify the global lithium supply chain.

Studies at Stanford University have shown that sediments in super-volcanic lakes preserved in craters have the potential to deposit large amounts of lithium clay.

The page contains the contents of the machine translation.