Plus 50 percent: charging trick improves overall battery life
US researchers have discovered a simple trick for charging new lithium-ion batteries that should significantly improve their service life.
Researchers have found a trick that appears to significantly extend the service life of lithium-ion batteries.
(Image: IM Imagery/Shutterstuck)
Longer battery life cycles could prove indispensable for improving e-vehicles and energy storage in power grids. Manufacturers of lithium-ion batteries can use the new charging method immediately. They do not need to change the chemical composition of the batteries.
One of the researchers involved, William Chueh from Stanford University in California, told the online science journal New Scientist that it would instead be sufficient to adapt the final step of the manufacturing process and slightly change the way new batteries are charged for the first time. During this process step, also known as forming, the performance characteristics of the batteries are significantly affected. Charging the batteries at low voltages for several hours during the forming process is apparently common practice.
Chueh and his colleagues found that charging the new batteries at high voltages significantly increases the number of charging processes possible per battery.
Discovered with machine learning
Using machine learning, they identified voltage and temperature as the most important factors influencing battery performance during this first charging process. They verified the results of the data analysis using experiments on 186 batteries.
The researchers' discovery contradicts established industry knowledge, as charging the batteries at a higher voltage during formation inactivates more lithium ions in a new battery than charging at a lower voltage during the initial charge. How many lithium ions are active, i.e. flowing back and forth between the negative and positive electrodes, is decisive for how much charge a battery can hold.
However, the initial loss of ions creates space in the positive electrode, which, according to the researchers, increases the efficiency of charging and discharging. The inactivated lithium ions also help to slow down the wear and tear of the battery.
Videos by heise
Batteries that were charged with a high voltage during formation had an average service life that was 50 percent longer. To illustrate this: So if the battery of an e-car had an average service life of 1500 charging cycles, it could increase this to an average of 2250 charging cycles using the new procedure.
(kst)