Phosphorus-carbon battery electrodes charge quickly

If car companies could offer electric vehicles with batteries that recharged in the amount of time it takes to fill a gas tank, they might find a bigger market. Yi Cui, a battery chemist at Stanford University, believes lithium-ion battery anodes based on phosphorus could help realize this vision. His team now reports anodes made from phosphorus mixed with carbon that can recharge in about 8 min (Joule 2019, DOI: 10.1016/j.joule.2019.01.017). Researchers including Cui have previously made and tested phosphorus-based electrodes and found that they can store a large amount of energy in a given footprint. Now Cui’s research group has found another advantage of the material: it allows fast charging. To speed up the charging process, most anode materials must be recharged at voltages that are close to the potential at which lithium plates, causing the metal to coat the electrode and ruin the battery. But phosphorus-based anodes, Cui says, can be recharged quickly at about 500 mV, which is far from the plating voltage. Cui’s group made phosphorus-carbon composites (scanning electron micrograph shown) and formed them into fast-charging battery anodes. But before these electrodes find their way into the batteries of electric cars, researchers will need to pair the anodes with fast-charging cathodes.