Researchers from SLAC National Accelerator Laboratory under the US Department of Energy and Stanford University have just introduced a method that can greatly restore the efficiency of rechargeable lithium batteries. For electric vehicles and the next generation of electronic equipment, this means that the battery life of related products can be further extended. It is reported that lithium batteries will form lithium islands with low activity between electrodes after multiple charge and discharge cycles, thus reducing the energy storage effect of the battery.
(Image from: Greg Stewart /Slac National Accelerator Laboratory)
The good news is that the researchers found that they can make the "dying" lithium island walk like a bug to one of the electrodes until it is reconnected, thus partially reversing the process of bad attenuation.
According to the research published in Nature on February 22nd, 2002165438, the team can extend the life of lithium batteries by nearly 30% by introducing this extra step.
Fang Liu, a postdoctoral researcher at Stanford University, said: "We are now exploring the possibility of using extremely fast discharge steps to recover the capacity loss of lithium-ion batteries."
As shown in the above figure, when an inactivated lithium metal island moves to the anode (or cathode) of the battery and reconnects, it can be restored to life, used for charge storage and provided support for electron flow.
The following animation shows the principle of the experimental device and explains how the "dying" lithium island wriggles back and forth between the anode and cathode (red and blue) during the battery charge and discharge cycle.
Considering that lithium batteries have been widely used in mobile phones, laptops and electric vehicles, a large number of research teams are looking for rechargeable battery solutions with lighter weight, longer life, higher safety and faster charging speed.
One of the development directions is lithium metal battery, which can store more capacity and charge more efficiently with the same weight per unit volume. If popularized, the next generation of electric vehicles can occupy less weight and space, or achieve longer cruising range with the same battery volume.
However, both solid-state batteries and lithium-ion batteries use positively charged lithium ions to shuttle back and forth between the poles. Over time, some metallic lithium will be electrochemically inert, forming lithium islands that are no longer connected to the electrodes, resulting in capacity loss.
For detailed information about this research, please refer to the February 22nd issue of Nature, 202 1 65438.
The original title is the dynamic spatial progress of isolated lithium during battery operation.