Supercapacitators: is speedy charging on the horizon?

By

We’ve all been there – that desperate time where your phone or laptop’s battery is right on the edge of dying, and you’re frantically looking for a power socket. Imagine if, in those moments, you could plug in and have a full charge in just 1 minute. This dream might not be so far-fetched thanks to a recent breakthrough in superconductors!

Published several weeks ago in PNAS, Ankur Gupta (University of Colorado) and his lab, discovered how ions move within a complex web of microscopic holes of carbon called ‘pores’. Such a breakthrough could lead to the development of more efficient energy storage devices, such as supercapacitors, according to Professor Gupta, whose background is in chemical and bioengineering.

Rather surprisingly, they utilised and adjusted the parameters of Kirchhoff’s law, a major law for the flow of currents in circuits – and something we’ve all looked at during our GCSE years. This law only applies to electrons: ions behave differently in the sense that their movements are affected by both the diffusion of particles and that of electric fields. The researchers realised that their movements at pore intersections are different from what was described in Kirchhoff’s law.

Supercapacitors are energy storage systems that rely on build-up of ions in such pores and have considerably quicker charging times than that of batteries and are much slow to deteriorate. Before this study, ion movements were only documented in the literature within a single, linear pore. This research now enables the simulation and prediction of ion movement within a complex network of thousands of interconnected pores in just a few minutes.

The environmental implications of this breakthrough are significant. Traditional batteries used in our precious devices, particularly lithium-ion batteries, have a substantial environmental footprint. They require rare earth metals, involve environmentally damaging mining processes, and often end up in landfills where they can leach toxic chemicals. Supercapacitors, however, are usually made from more abundant and less toxic materials, such as carbon. This reduces the environmental damage associated with raw material extraction. Not to mention how supercapacitors have much longer lifespans than batteries, meaning fewer replacements and less electronic waste. This durability could lead to a significant reduction in the electronic waste that currently pollutes our environment.

Supercapacitators are fast, but are larger than traditional batteries

The efficiency and speed of supercapacitors make them ideal for use with renewable energy sources. They can store and discharge energy quickly, which is perfect for balancing the intermittent nature of solar and wind power, as well as for power grids in general, since fluctuating demand for energy essentially needs efficient storage to avoid waste during periods of low demand and to ensure rapid supply during high demand. This can help to reduce reliance on fossil fuels and lower greenhouse gas emissions.

“The primary appeal of supercapacitors lies in their speed,” Gupta said. “So how can we make their charging and release of energy faster? By the more efficient movement of ions.”

But what could Dr Gupta have missed? Well, supercapacitors usually have a considerably lower energy density compared to traditional batteries, which means prevents them from storing as much energy in the same amount of space, which is a critical factor for many applications, especially in smaller portable electronics and electric vehicles. There’s also the issue of their energy retention – unlike our current mainstream batteries, which can hold onto more energy when not in use, supercapacitors discharge far quicker, which would be incredibly off-putting to most electric car manufacturers who pride themselves on how they last longer than internal combustion engine car manufacturers. And finally, as well as perhaps the most important: the cost. Commercialising such a technology faces serious technological challenges as supercapacitors require serious precision as the sizes of pores must be uniform; the electrolytes have to be consistently applied across the supercapacitor; and their usual materials (graphene and carbon nanotubes) are much more sophisticated and complex than the traditional battery.

Overall, Dr Gupta presents a potentially beautiful future for the battery with a source of energy with a vast range of applications from smaller tech to massive power grids, but fails to acknowledge the massive obstacles that come alongside the development of such technologies. Cost; long-term energy retention; and energy density are crucial for commercial manufacturers, and there’s no way that Gupta’s discoveries could be scaled up to mainstream commercial technology unless the manufacturer is prepared to deal with major losses and a sudden increase in the sizes of his products, which can prove fatal in an age where we love how our technology is only getting smaller.

Image: Tomwsulcer via Wikimedia Commons

Leave a Reply

Your email address will not be published. Required fields are marked *

 

This site uses Akismet to reduce spam. Learn how your comment data is processed.