In the transition to sustainability, our world is experiencing soaring demand for renewable energy, and batteries will play a critical role. Energy storage is key to decarbonising our power systems and reducing greenhouse gas emissions. It is also essential for building reliable and affordable electricity grids that can handle fluctuating renewable energy sources like wind and solar.
By 2026, global renewable energy generation is forecast to match total fossil fuel and nuclear output. Electric vehicles (EVs) passed 10% of global vehicle sales in 2022, and are on track to reach 30% by the end of the decade. Last year’s sales rose to 10,5 million worldwide. New applications are also coming into play, such as electricity storage on the grid that can help balance out wind and solar sources. Government policies are going to accelerate this growth.
There are various energy storage solutions available, but lithium-ion batteries dominate as a result of their cost-effectiveness and efficiency. Demand for lithium-ion batteries is skyrocketing.
New batteries
Most EVs are powered by lithium-ion batteries, a decades-old technology. All those years of development have helped push prices down and improve performance. According to Our World in Data, the price of lithium-ion batteries has dropped by 97% over the past three decades, and halved between 2014 and 2018. Now the search is on for the battery of the future – one that is more powerful, faster charging, cheaper, smaller, longer lasting, safer, and more sustainable; and there is an explosion of research and development going on which is pushing the boundaries of the technology.
Concerns about supplies of key battery materials like cobalt and lithium are also driving the search for alternatives to the standard lithium-ion chemistry. Shrinking the size of batteries, and at the same time providing them with more capacity, also carries greater risks. We all remember the exploding Samsung S7 Note batteries a few years ago. Today, the goal for batteries is not only that they last longer, but also that they can be charged much faster. The aim is to get hours of use from just a few minutes of charging.
Solid-state batteries
Standard lithium-ion batteries use a liquid electrolyte. Solid-state batteries replace this liquid with ceramics or other solid materials. This results in greater energy storage with longer life, and greater safety with less toxicity. It is possible to pack more energy into a smaller space. Solid-state batteries can move charge around faster, meaning shorter charging times; and with no flammable solvents they improve safety by cutting the risk of thermal runaway and fire hazards. They can use a wide range of chemistries, but the main option for commercialisation is still lithium.
Sodium-ion batteries
However, with concerns about lithium, sodium-ion batteries are attracting attention. These batteries have a design similar to lithium-ion batteries, including a liquid electrolyte, but use sodium as the main chemical ingredient, a far more abundant metal. Sodium-ion batteries may not improve performance, but they can cut costs because they rely on cheaper, more widely available materials than with lithium-ion chemistry. Companies going after this technology, like US-based Natron, are targeting less demanding applications like stationary storage. Chinese battery giant, CATL will begin mass producing them this year.
Stationary storage
Battery energy storage systems (BESS) are rechargeable batteries that can store energy from different sources and discharge it when needed. They can be used to balance the electric grid, provide backup power, and improve grid stability. They will play an increasingly important role in balancing green energy supplies with electricity demand.
BESS has advantages over traditional grid storage solutions such as greater flexibility, greater scalability, lower costs and higher efficiency. BESS also makes it easier to sell energy back to the grid through a smart minigrid, and can generate new revenue streams and reduce electricity bills through energy arbitrage and peak shaving. Here in South Africa, global companies like USP&E; and ACTOM are starting to provide BESS to alleviate loadshedding.
Although lithium-ion batteries are currently the most economically viable BESS solution, there are a number of other technologies currently being developed. One rising BESS star is iron. US company, Form Energy is developing an iron-air battery that uses a water-based electrolyte and basically stores energy using reversible rusting. Its manufacturing facility is scheduled to begin construction this year.
One possibility is compressed air energy storage. Here surplus power is used to compress air and then store it. When energy is needed, the compressed air is released and passes through an air turbine to generate electricity. Another technology is flow batteries that store energy in external liquid tanks, which can last more than a decade without degrading. One such battery developed at Harvard University uses organic molecules dissolved in pH-neutral water, a formulation so stable that the batteries lose only 1% of their capacity for every 1000 cycles. They are also considerably safer, as the solution contains no corrosive or toxic elements.
Another possibility is mechanical gravity energy storage (GES), covered elsewhere in this guide. Gravity-based systems use a mechanical process of lifting and lowering huge blocks to store and dispatch electrical energy, applying the fundamental principles of gravity and potential energy.
Fast charging
Meanwhile researchers are exploring new ways to speed up the charging process, which depends on the speed of the transport of lithium inside the electrodes. Faster charging is of particular interest for EVs because they are limited by recharging time. The lifespan of a battery is about 1000 cycles, and scientists are looking for ways of extending the lifetime by fast charging, while avoiding lithium deposition at the anode. Research has also found methods to speed up the movement of lithium by adding large metal ions such as potassium. Researchers are also exploring possible new avenues such as replacing batteries with flexible cable-like supercapacitors that could give a full charge in seconds and a lifetime of 30 000 charge/discharge cycles. These batteries would take up much less space than today’s batteries.
1000 km on a single charge
EV range has quadrupled in the last decade. 1000 km on a single charge is now becoming a reality, after the world’s biggest EV battery maker CATL announced a breakthrough that will go into mass production this year. CATL claims that its new condensed battery can store almost double the power of Tesla’s top-of-the-range equivalent, which was hailed as a game-changer only months ago with its reported range of 450 km. As well as opening up the possibility of long-distance motoring, CATL says it is shattering the technological barriers to the development of electric-powered passenger flight. CATL achieved this breakthrough by developing a semisolid-state battery using partially solid electrolytes, which gives it greater energy density over the usual liquid or gel electrolytes.
In further exciting progress, a Volkswagen-backed rival is already snapping at CATL’s heels, having announced plans to bring a 1000 km range battery to the mass market. Gotion High Tech, also based in China, says its lithium-manganese-iron-phosphate Astroinno battery will begin mass production in 2024. The packs can fast-charge in 18 minutes, passing all safety tests, and they have a lifetime of 3,8 million km. The number of parts needed to build the battery is down 45%, while the weight of the parts is down 32%. Volkswagen is one of Gotion’s first customers.
Meanwhile researchers at the National University of Singapore are developing batteries that can charge as quickly as a tank refill. These batteries are made with niobium and graphene and are engineered to last ten years longer than the standard EV battery. Graphene has exemplary electrical conductivity, while niobium has a stress-resistant molecular structure that can prolong the battery’s lifespan and prevent overheating. Researchers estimate that the niobium-graphene batteries will be able to charge at least 10 000 times and retain 80% of their starting capacity − five times higher than current EV batteries. The researchers estimate their battery will complete its charge within ten minutes − about three times faster than the average for current EV battery fast-charge rates. The longer battery lifespan will also reduce the cost of ownership of an EV.
What about the minerals
Building the wind and solar farms, and the battery and electricity networks we need to run our systems on renewables, will require a huge array of mined minerals, and there is a scramble for the lithium, nickel, cobalt and other minerals used to make the batteries that power them. Global lithium output is on track to triple this decade, but sales of EVs threaten to outrun that. Each battery requires about eight kilograms of lithium, plus cobalt, nickel and other metals. The numbers are staggering. The International Energy Agency estimates a sixfold increase in demand for these minerals by 2040 to meet climate targets. We will need 21,5 million tons for electric vehicles and battery storage alone. Worldwide lithium resources are estimated at 80 million tons by the US Geological Survey. Forecasts of annual production range are as high as 1,5 million tons by 2030. But if EV sales keep rising at double-digit annual rates, demand is forecast to increase to up to 3 million tons.
The catch-22
Although EVs consume less power and emit fewer greenhouse gases than fuel-powered vehicles, their batteries require more minerals – especially lithium. About two thirds of the world’s lithium comes from mines. In addition to using toxic and corrosive compounds, lithium-ion batteries have a high environmental cost due to the extraction of the metals used in their production. This involves crushing rock and using acids to extract metals, leaving toxic heaps of chemical-laced tailings.
One looming problem relates to sulphuric acid. As the rapidly expanding use of low-carbon technologies increases, by 2050 cobalt demand could increase by 460%, nickel by 99%, and neodymium by 37%. All of these are currently extracted using large quantities of sulphuric acid; but more than 80% of the global sulphur supply is a waste product, extracted from fossil fuels to reduce emissions of sulphur dioxide. Eliminating fossil fuels to rein in climate change will drop the supply of sulphuric acid just as demand is increasing. A rapid reduction in the fossil fuel use required to achieve net zero emissions by 2050 could create a shortfall of sulphuric acid as large as 320 million tons by 2040, or 130% of present day production.
The answer to the question of “Are electric vehicles really eco-friendly?” largely depends on how we manage the downsides associated with their batteries. Changes in how we design, produce, use and recycle electric car batteries are urgently needed to ensure that while solving the problem of fossil fuel emissions, we also minimise other environmental harms. This needs some political will.
The political scene
A shortfall in lithium supplies would be an obstacle for plans to ramp up sales of EVs to tens of millions a year. The issue is fuelling political conflict over resources, and complaints about the environmental cost of extracting them. Threatened by possible shortages of lithium for electric car batteries, automakers are racing to lock in supplies of the once obscure ‘white gold’ in a politically fraught competition ranging from China to Nevada to Chile. Supply uncertainty is pushing companies to take measures to secure long-term lithium sources. Companies like General Motors and Ford are buying stakes in lithium mines and tying in lithium suppliers. Volkswagen and Honda are trying to reduce their need for mined ore by forming recycling ventures. Others are investing in lithium refining or ventures to recycle the metal from used batteries.
Beijing, Washington and other governments see metal supplies for electric vehicles as a strategic issue and are tightening controls on access. Last year Canada ordered three Chinese companies to sell lithium mining assets, on security grounds. Other governments including Indonesia, Chile and Zimbabwe are trying to maximise their return on deposits of lithium, cobalt and nickel by requiring miners to invest in refining and processing before they can export. In South America the ‘lithium triangle’ comprising Argentina, Bolivia and Chile holds about 60% of the world’s reserves and is talking about nationalisation and cartels – the OPEC of lithium.
A key issue for the industry is how to ensure the minerals needed for the energy transition are sourced responsibly. If we are destined to continue mining for the minerals needed for the energy transition, how can this be done responsibly and how can we mitigate the impact of the mining?
Recycling
One solution is recycling. Greater use of electric vehicles is good news for the climate, but batteries are the environmental Achilles heel of EVs unless we repair, reuse and recycle them. Recycling Li-ion batteries, which can explode if not treated with care, has until now been prohibitively expensive, and older methods of processing spent batteries struggled to reliably recover enough of these individual metals to make recycling economical. But new approaches have swiftly changed that, enabling recyclers to dissolve the metals more effectively and separate them from battery waste. A growing number of recycling companies are drawing on developments in hydrometallurgy. These advances in recycling are helping to alleviate the environmental damage caused by mining, and contribute to a circular economy.
China leads the world in battery recycling today, dominated once again by major battery companies like CATL. The EU has recently proposed extensive recycling regulations; and companies in North America are quickly scaling operations, funded by billions of dollars in public and private investment. Redwood Materials in Nevada aims to make enough recycled materials for five million EV batteries by 2025, and create a circular supply chain for electric vehicles. Li-Cycle in Toronto is ready to begin commissioning its main recycling facility this year.
Recycling facilities are now capable of recovering nearly all of the cobalt and nickel and over 80% of the lithium from used batteries and manufacturing scrap left over from battery production − and recyclers can resell those metals for a price nearly competitive with that of mined materials.
Conclusion
There is a huge amount going on in the battery arena, and the big companies and countries, are starting to ‘put their money where their mouth is’. I think the answer to the energy conundrum will consist of a lot of small things that add up to something big in this mix of rapidly evolving technologies. 2030 will be here before we know it, and by 2050 our world will be a very different place energy-wise.
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