Sand, seawater or wifi? New (and surprising) materials for EV batteries
Lithium-ion batteries, near standard in EVs today, are on the way out. A crowded field of replacements is fighting to become the next big thing. Looking even further, your EV may one day soon be powered by sand, seawater… or simply wifi radiation – as proposed by Nikola Tesla himself.
We’ve come a long way since the Nissan Leaf. Introduced in 2010, the BEV that kickstarted the electrification era was equipped with a 24-kWh lithium-ion battery, and came with a range of about 100 miles (160 km).
Today, the Lucid Air Performance has an official EPA range of up to 520 miles (836 km). An exceptional performance, showing the great strides made in battery technology in 12 years’ time.
Like the Leaf, Lucid Motors uses lithium-ion technology for its batteries. However, the eye-watering price - ranging from $78,000 to $179,000 is an indication that lithium-ion technology suffers from serious disadvantages.
Many of the various minerals used to make lithium-ion batteries are scarce, and thus expensive. This is most prominently the case for lithium, the material most used for lithium-ion batteries.
But there are more concerns than just price. Mining the minerals often leads to environmental destruction, and sometimes relies on questionable labour practices (including child and slave labour); the latter is especially the case for cobalt.
And you can add to that list of issues the terminally dwindling reserves of certain battery minerals, the fact that lithium-ion battery technology presents a small, but persistent and as yet unsolved risk of catching fire, and last but not least China’s strategic stranglehold on the EV battery market (with CATL having a market share of around 30% in 2021, and various Chinese companies supplying 85% of the industry’s cobalt in 2020).
As the EV market grows in spurts, these problems are magnified to the extent that battery issues could threaten to derail the progress of electrification itself. This is forcing the automotive industry to do what it does best: innovate itself out of a tight spot. So, what are the options? Let’s look at the state of battery technology today, tomorrow, and beyond.
Battery technology today
Most BEVs and PHEVs today use lithium-ion batteries. The specific materials used vary, giving rise to various types of lithium-ion batteries, notably LFP (lithium-phosphate), NMC (lithium, manganese and cobalt), and NCA (nickel, cobalt and aluminium). Lithium-ion batteries have a longer lifespan than other battery types, and up to 95% of the materials can be recycled. Those other battery types each have their own advantages and disadvantages:
Nickle-metal hydride (NiMH) batteries
These are the main alternative to lithium-ion batteries. They’re generally used in hybrid EVs (HEVs). They’re cheaper and more resistant to cold than lithium-ion batteries, but have around 40% less energy capacity.
12V lead batteries are a critical component of EVs, but merely provide auxiliary power, mainly supporting safety-related features. They have low cold resistance and a short lifecycle.
Used for power storage, supercapacitors can charge and discharge energy quite fast and boost EV battery storage capacity. However, because of their lower energy density, they can’t be used as the sole source of power for EVs.
Battery technology tomorrow
So, what are the emerging options for EV batteries tomorrow? As mentioned, the field of candidates is quite crowded. Here are nine of the most promising technologies.
Solid-state batteries (SSBs)
By using a solid electrolyte instead of a liquid one, SSBs provide higher energy density using less space. As a result, range increases, charging time (slightly) decreases, EV weight goes down, and there’s more cargo space. Additionally, SSBs are more fire-resistant, and have a longer lifecycle. A 2021 Harvard study says lithium-metal SSBs can be recharged at least 10,000 times.
One of the first alternatives to lithium-ion. Use less harmful materials, cheaper, more fire-resistant, and provide up to three times the energy density. One major problem: the very short lifecycle, of just 1,000 recharges. Lyten is one of the few manufacturers of this battery type.
Lithium-iron phosphate (LiFePO4) batteries
A replacement for lead-acid batteries that offers many advantages, with a lifecycle of around 5,000 recharges, an energy density four times higher, and being non-toxic (no cobalt!) LiFePO4 batteries are around 50% lighter than other lithium batteries, highly resistant to high temperatures, and almost 78% of the materials can be recycled. Applicable in many industries, LiFePO4 batteries have few manufacturers, one being Super B.
Sodium-ion (Na-ion) batteries
The shortage of lithium is pushing many battery producers, including CATL, to replace the main material with sodium, as the material is a thousand times more abundant. If lithium prices continue to go up, CATL and Reliance Industries, which acquired UK-based Faradion last year, are expected to lead the Na-ion market, which is also an adversary of the LiFePO4 alternative.
In 2017, Sydney University started work on zinc-air batteries. Today, making the battery rechargeable is the only remaining major obstacle. Zinc-air batteries are smaller and lighter than lithium-ion ones, and some experts believe they will provide up to 500% more power, at less than half the cost.
Structural component batteries
Developed by the Chalmers University of Technology in Gothenburg, these batteries contain carbon fibre that serves as an electrode, conductor and load-bearing material. The battery has around 20% capacity compared to lithium-ion, but researchers believe it will be ideal as EV weights are going down.
Ultra-Fast Carbon battery
Patented by NAWA Technologies in France, this battery with ultra-fast carbon electrode design has the potential to increase battery energy ten times and the life cycle by five times. Whether this innovation will revolutionise mobility, will become apparent from 2023, when it will go into production.
Developed by CATL and fellow Chinese battery producer SVOLT, this technology is also being improved by the University of Texas. NMx cells, developed by SVOLT consist of 75% nickel and 25% manganese. Current research is based on making the technology cheaper and more sustainable.
Silicon anode battery
Using electrochemical etching, researchers at the University of Eastern Finland developed a self-standing mesoporous silicon film anode, which can handle volume expansion during cycling. This could be the ‘Holy Grail’ of battery technology, with an energy storage capacity almost ten times that of the graphite anodes in lithium-ion batteries.
Battery technology in the future
While many scientists are hard at work on the EV battery technologies of tomorrow, some already dare dream of what may be possible in the future. Such as:
Skipping rare earth minerals entirely, scientists at IBM launched the idea of using materials extracted from seawater. In development by IMB Research’s Battery Lab, the ‘seawater battery’ would cost less, charge super fast, have a higher energy density, and be more fire-resistant than the lithium-ion battery. On top of that, it would eliminate the human and environmental cost of mineral mining.
Graphite, which used for the anode in lithium-ion batteries, can be replaced by nanoscale silicon for a performance boost. However, nanoscale silicon degrades quickly and is hard to produce. Fortunately, it can – in theory – be replaced by silicon dioxide, commonly found in quartz and the main ingredient in sand. That’s what researchers of the University of California have been working on since 2014.
In 2024, 58% of EV charging poles will use cellular or wifi technology, and Bluetooth, predicts Swiss semiconductor company U-blox. Advanced connectivity (via the Cloud and 5G) is just the beginning: some researchers say it will be possible to use radio frequencies to charge EVs. That sounds a lot like Nikola Tesla’s ultimate energy solutions. He proposed transmitting energy over the air, in the upper atmosphere.
The final futuristic idea – for now – comes from Tel Aviv University. Using ‘nanodots’ derived from organic material, the prototype battery can charge smartphone batteries in 30 seconds. Nanodots boost electrode and electrolyte capacity, offering superfast charging for mobile device batteries. Still in the research phase, biological semiconductors may someday be used in EV batteries.
As this litany of technological options demonstrates, technology will provide an answer to the current problem with lithium-ion batteries. Which technology will be the standard of the future? We don’t know, but it’s likely you’ll have read about it here first…
The main photo is courtesy of Shutterstock. The first in-article photo shows lithium-sulphur batteries of Lyten, courtesy of Lyten. The second in-article photo shows the sodium-ion battery prototype of CATL, courtesy of CATL. The last photo shows a scientist working at IBM's Research Lab, courtesy of IBM.