Quantum batteries are now closer to reality, and it will make electric vehicles (EVs) and other electric-powered devices more fascinating. Usually, most people seem to use lithium-ion batteries. But with the concept of Quantum batteries, one can get ‘no loss’ of energy supply for their devices without causing any environmental damage or use Quantum batteries as a power source for space missions.

Quantum batteries could one day revolutionize energy storage through what seems like a paradox – the bigger the battery, the faster it charges. For the first time, a team of scientists has now demonstrated the quantum mechanical principle of super-absorption that underpins quantum batteries in a proof-of-concept device.

In a step towards offering an even better energy source, researchers at the University of Adelaide and their overseas partners have successfully proved the concept of super absorption, the backbone for making quantum batteries a reality. Upon development, quantum batteries can significantly impact energy capture and storage in renewable energy and miniature electronic devices.

Quantum Batteries and How They Work?

The idea of creating a nanometre-sized Quantum battery belongs to scientists of the University of Alberta and the University of Toronto in Canada. The working of Quantum batteries has completely different principles than usual. Unlike Lithium-ion batteries which work due to the 

chemical reactions inside the cell. Quantum batteries work on Quantum Mechanics principles. The Nano-Structured Solid State of matter with electrons absorbing photons to become stable in this state allows particles to hold energy and remain in the device for an indefinite time. Then this energy can be used to create a quantum battery.

The Genoa team proposes housing multiple two-level quantum systems, or qubits, inside a single optical cavity. Light with a specific wavelength is shone into the cavity – in the form of a laser pulse, for example, exciting the qubits from their ground to excited states while simultaneously entangling them. This arrangement, the researchers calculate, increases the device’s charging power in proportion to the square root of the number of qubits. At the same time, the charging rate remains flat if qubits are housed in separate optical cavities. As Polini.C, Senior Scientist, puts it, using a common cavity means that “every qubit talks to every other qubit”.

Polini says that their system doesn’t violate any laws of thermodynamics since it merely involves a higher rate of energy flow from source to the battery than is possible conventionally, rather than any increase in the total amount of energy. The scheme involves a trade-off between charging power and stored energy, with the balance between the two determined by how strongly photons and qubits are coupled to one another.

While theoretically, Polini explains that the research is more practically oriented than previous work. “Historically, the few papers in the literature on quantum batteries come from scientists in the quantum information community, who are more interested in fundamental theorems than in actual solid-state implementations of their ideas, we read their papers [on quantum batteries] and saw that this can be done in the lab.”

“Quantum batteries, which use quantum mechanical principles to enhance their capabilities, require less charging time the bigger they get” said Dr. James Q. Quach, who is a Ramsay Fellow in the School of Physical Sciences and the Institute for Photonics and Advanced Sensing (IPAS), at the University of Adelaide.

“The active layer of the microcavity contains organic semiconductor materials that store the energy. Underlying the superabsorbing effect of the quantum batteries is the idea that all the molecules act collectively through a property known as quantum superposition," said Dr. Quach.

As the microcavity size increases and the numbers of molecules are increased, the charging time decreases. This is a significant breakthrough and marks a major milestone in the development of the quantum battery.

Predictions by Scientists

The idea of the quantum battery has the potential to significantly impact energy capture and storage in renewable energy and in miniature electronic devices at that. By 2040, energy consumed by people is expected to increase by 28 percent from 2015 levels. The majority of energy will still come from fossil fuels at great cost to the environment. A battery that is capable of harvesting and storing light energy simultaneously would provide significant cost reduction while reducing the unpredictability of energy from solar technologies. A new vista in battery technology, driven by the power of quantum mechanics, could become a reality by applying for work.

“Quantum batteries have a counter-intuitive property in which the recharge time is inversely related to the battery capacity, that is, the amount of stored electrical charge. This leads to the intriguing idea that the charging power of quantum batteries is super-extensive, meaning that it increases faster with battery size.”

 

The fabricated device is a microcavity in which the active material consists of organic molecules dispersed in an inert matrix,” says Tersilla Virgili of the Institute of Photonics and Nanotechnologies in Milan.

“Each molecule represents a unit that can exist in a quantum superposition state of two energy levels (fundamental and excited), similar to the way a qubit, the basic unit of quantum information, can be both zero and one simultaneously in quantum computers. In the future this type of device can be applied in various scientific and technological fields such as wireless chargers, solar cells and cameras”, concludes Virgili. 

A team of scientists from the universities of Alberta and Toronto has laid out the blueprints for a ‘quantum battery’ that never loses its charge. To be clear, this battery doesn’t exist yet, but if they figure out how to build it, it could be a revolutionary breakthrough in energy storage. “The batteries that we are more familiar with — like the lithium-ion battery that powers your smartphone — rely on classical electrochemical principles, whereas quantum batteries rely solely on quantum mechanics,” said Gabriel Hanna, chemist, University of Alberta.