Lithium-ion batteries. Credit: Andrey Klemenkov/iStock
Since they were first commercially introduced in 1999, lithium-ion batteries have become an integral part of modern technology and, consequently, of our modern way of life.
They power almost every smartphone, laptop, and tablet sold today across the world. And their role will likely prove to be even more important in the future, as electric vehicles (EVs) are still an emerging market. Such vehicles – which include not only electric cars, but also electric motorcycles, buses, or trucks – are bound to replace conventional petrol-fuelled, further driving the demand for high-density lithium-ion (Li-ion) batteries.
Batteries are also under-exploited in power supply systems, especially in combination with photovoltaics and wind power, where they’re poised to massively reduce carbon emission. There is arguably no other piece of material science that has touched the way of life of everyone on this planet like Li-ion batteries have.
This achievement was made possible by the work of John B. Goodenough, M. Stanley Whittingham and Akira Yoshino. Their pioneering work was recognised by the Royal Swedish Academy of Sciences, who in 2019 awarded them the Nobel Prize in Chemistry “for the development of lithium-ion batteries”. (Learn more about their research in this previous blog post.)
The future seems bright for lithium-ion energy storage, but what can we expect?
Why Li-Ion Batteries are Amazing Energy Storage Devices
The Li-ion battery (LIB) works similar to other batteries. Its major difference however is that the electrodes are not as strongly affected by chemical reactions. The Li-ions flow from the negative anode to the positive cathode while discharging and vice-versa when charged.
The main reason why LIBs are so popular is owed to their impressive energy density (100-265 Wh/kg or 250-670 Wh/l, depending on the number of lithium ions the electrodes can hold per unit of surface area). This enables mobile devices to draw their power from a very small space. LIBs offer short charging times and can run a high number of discharge cycles before they run out, compared to other battery technologies, such as nickel-cadmium or nickel metal hybrid.
The main shortcoming of LIBs is safety. LIBs tend to overheat and can become damaged beyond repair at high voltage. In extreme cases, Li-ion power systems can even combust as observed with the Galaxy Note 7 smartphone, whose battery defect caused some phones to catch fire. A similar problem caused the grounding of a Boeing 787 fleet. Nowadays, manufacturers are required to implement sophisticated safety mechanisms that limit the voltage and internal pressure.
The Future of Li-Ion Energy Storage
The largest market for Li-ion batteries has traditionally been portable electronic devices but there is also an extensive growth in the demand for LIBs in transportation. As electric vehicles are on a path to match conventional cars in terms of price and distance range, it might only be a matter of time before most or all road transportation is electric — powered by LIBs, of course. Today, it’s not uncommon for an EV to last 360-450 kilometres per charge. With the improvement of energy density the car’s autonomy will be increased, making EVs more viable.
Fast charging is another key aspect. Dr. Chao-Yang Wang, professor at Pennsylvania State University, and collaborators used a special setup to charge a LIB to 80% in 10 minutes without damaging it. “The 10-minute trend is for the future and is essential for adoption of electric vehicles because it solves the range anxiety problem,” Wang said in a press release.
The impact of LIBs in transportation also includes aerospace applications, from drones to satellites. The Israeli firm Eviation is working on a prototype of a completely electric aircraft that will be able to carry nine passengers for up to approx. 1 000km at 3 000m and 440km/h — all powered by batteries.
LIBs will also prove essential in tackling climate change, by supplying vehicles and our households with renewable energy. Renewable energy depends on environmental factors. Solar panels don’t generate power at night nor do turbines during low wind. The race is among researchers right now to find the most optimal and cost-effective solution to store that energy in order to make it price-competitive with fossil-powered plants.
Already, batteries produced in new factories in China, the U.S., Thailand and elsewhere are driving down prices tremendously. They have plunged 85% since 2010. If this trend continues, it is possible that the electricity grid of the future will be largely supported by energy storage systems based on Li-ion batteries. LIBs can cause an increase in energy decentralisation as more people employ energy storage systems in conjunction with rooftop solar.
Keep in mind that where there is a need for technology, a demand for power follows. This also includes the world of miniature electrical devices.Substantial advances have been made in integrating LIBs in miniaturised medical devices like hearing aids or low-power implantable devices used for glucose sensing, neuro-stimulation, drug delivery, and more.
A Finite Resource
Li-ion batteries have tremendous potential to transit the world towards a 100% renewable future on a global scale.
However, such a transition needs to be carried out with responsibility. Lithium is sometimes referred to as ‘white petroleum’, a nod to the fact that it is a finite resource with a major environmental impact.If Li and other rare earths are mined using poor management practices it can result in significant carbon emissions and lasting environmental inpact. By the year 2025, lithium demand is expected to soar to 1.3 million metric tons of LCE (lithium carbonate equivalent) — that’s over three times today’s levels.
Towards this goal, it is important to minimise our dependence of cobalt, introduce battery collection and recycling schemes, exploit novel concepts such as second-hand batteries to exhaust battery cycle life before reaching the recycling plant, shift lithium extraction away from hard rock to brine, and promote market growth in order to take advantage of economy of scale effects.
Today, Li-ion batteries are already mainstream and mean big business. But, in the future, all projections suggest the technology is heading only one way — up. For instance, MIT’s Yet-Ming-Chiang claims there are three times as many scientists working in battery research in the US than there were just ten years ago. With all these researchers working on solving the biggest limitations faced by LIBs, innovation is bound to happen. Perhaps, the best use of LIBs is still sitting in a lab somewhere, waiting to be discovered.