Researchers have developed a hybrid supercapacitor with high energy density and charge speed
Researchers at the University of Queensland University of Technology (QUT) have developed a new hybrid supercapacitor that has a high charge and discharge speed, as well as a significant improvement in energy storage and performance similar to NiMH-Hydride Metal (NiMH) batteries.
Lithium batteries store energy chemically and are widely used due to their high energy density. Despite this advantage, we all know that these batteries do not charge very fast. In addition to batteries, we are dealing with super capacitors that store energy statically instead of chemically, so they charge and discharge much faster and, of course, their internal structure is not destroyed.
This feature allows super capacitors to have a high power density, but in contrast, has a much lower energy density than chemical batteries. Energy density (watts per kilogram) refers to the total amount of energy that a device can store for its weight, and power density (watts per kilogram) means the speed at which power is transferred during charging and discharging.
Researchers have turned to hybrid super capacitors that have moderate performance in terms of energy density and power density. Now, new research from the QUT University team has taken on a different design. The paper describes the design team using a negative capacitive “titanium carbide” electrode and a battery-like hybrid positive graphene positive electrode.
The result of such a design style is the achievement of a hybrid super capacitor with 10 times the power density or better charging capability than lithium batteries. In addition, the energy density of this hybrid capacitor is not much different from NiMH batteries.
Such a capacitor has a maximum energy density of 73 watts per kilogram, which is 28% of the best batteries used in today’s electric vehicles. In contrast, its power density reaches 1600 watts per kilogram, which is much higher than lithium batteries with a power density of 250 to 340 watts per kilogram.
If we want to compare the performance of these batteries in the real world, we can take a look at the Plaid Plus version of the Tesla Model S. This Tesla car has a range of nearly 840 km, which if we replace its batteries with a hybrid capacitor, its range will be reduced to 233 km. However, you can charge it up to 5 times faster with the required equipment.
In addition to high charging speeds, these hybrid super capacitors are up to twice as long as lithium batteries, according to the QUT team. In the experiments, after 10,000 full charge and discharge cycles, 90% of their capacity remained.
Despite such advantages, hybrid super capacitors are not expected to replace lithium batteries in electric vehicles in the near future, as the range of these products is of great importance to buyers.