The latest versions of Tesla charging stations allow owners of electric cars to quickly return to the road, but we are still very far from the moment when a full recharge of the car’s batteries will at least come close to the time required to fill the tank with liquid fuel. However, breakouts quite often occur in this direction, and the work of researchers from the University of Pennsylvania who created a new type of battery, the use of which will allow to fully charge an electric car in just 10 minutes, can be attributed to such breakthroughs.
The lithium-ion batteries that power our smartphones, laptops and electric cars are quite versatile and reliable to some extent. However, they are quite fragile systems, any deviation from the required charging and operating conditions leads to problems, to the formation of metal dendrites, for example, which cause short circuits and a complete battery failure.
Another factor affecting the operation of lithium-ion batteries is the ambient temperature. It is too cold – and lithium ions in the form of pure metal will begin to stand out on the anode of the battery, which is known as lithium metallization, this worsens the battery’s parameters and often leads to spontaneous combustion. Charging batteries at elevated temperatures is more efficient, but this can also have negative consequences in some cases.
“Heating batteries to an extreme threshold for them above 60 degrees Celsius is unacceptable when using conventional batteries,” wrote researchers from Pennsylvania. “High temperature poses a danger to some of the materials from which the battery cells are made. In addition, it has an extremely negative effect. on the electric capacitance and while the device is in use from that battery. ”
The new battery is designed to operate at temperatures that go well beyond the acceptable range of conventional batteries. When charging, it quickly heats up to a temperature of 60 degrees Celsius, which holds for the entire charge. After that, the battery is quickly cooled to ambient temperature due to nickel foil heat sinks that attach to the negative electrode. This same nickel foil works as a heater, allowing you to heat all the insides of the battery to the above temperature in just 30 seconds.
Studies have shown that this method of charging at temperatures from 49 to 60 degrees Celsius with subsequent rapid cooling allows you to completely avoid lithium metallization of the electrodes. Moreover, this technology of fast charging allowed to carry out 1700 charge cycles in a certain period of time. During the same time, at a battery temperature of 20 degrees, only 60 charging cycles could be performed.
“We demonstrated that in 10 minutes it’s quite possible to pump energy into the battery, which is enough for a distance of 320-480 kilometers,” the researchers write, “And the new battery can provide at least 2500 thousand charging cycles, which is equivalent to moving half a million miles,” which is enough for an ordinary person for almost his whole life. And now we are working on a technology that will allow the battery to be charged twice as fast, in 5 minutes, without causing physical damage to it. This requires the development of compositions of new ultra-stable electrolytes and other active materials for various battery cells. It will take some time, but we are confident that this task will be solved in the near future”.