Batteries of Tomorrow – How These 9 Innovations Will Transform Electromobility?
Innovative technologies are changing the face of batteries. The batteries of the future will be more efficient, safer, and cheaper. And they don't necessarily have to use lithium. What's even better is that these innovative batteries are expected to become widely available as early as 2024. We are examining how they differ from current designs and where they will be used.
Innovative technologies are changing the face of batteries. The batteries of the future will be more efficient, safer, and cheaper. And they don't necessarily have to use lithium. What's even better is that these innovative batteries are expected to become widely available as early as 2024. We are examining how they differ from current designs and where they will be used.
29 September 2023
Despite the limitations that lithium-ion battery makers are gradually, albeit slowly, overcoming, electromobility is gaining popularity, and it’s difficult to imagine reversing this trend. Furthermore, we now need efficient and affordable cells not only in electric vehicles and scooters or EVs but also in home renewable energy installations. Modern lithium-ion technology appears to be reaching its maximum energy density. However, there is no reason to worry because in a year or two, lithium-ion cells will be supplemented by other technologies whose capabilities today seem almost unreal. Discover the greatest innovations in the electric cell industry.
Solid-State Batteries to Revolutionize the World
For years, enthusiasts of electromobility have been excited about solid-state battery technology (All Solid-State Battery, ASSB), which provides high energy density. In addition, in 2022, a Silicon Valley startup called Quantum Scape built a solid-state battery that charges up to 80% in just 15 minutes and allows an electric vehicle (EV) to travel 640 km on a single charge. This cell uses a dedicated ceramic material whose composition is a secret. A semiconductor is placed between the anode and cathode, replacing the liquid electrolyte, and its structure allows ions to flow without causing short circuits. The technology is promising, but we’ll have to wait until at least 2025 to fully utilize its potential in e-cars.
Nissan and Toyota are also working on semiconductor batteries, with Toyota announcing the installation of solid-state cells in its vehicles as early as 2026 as part of its $13.6 billion research program.
It’s hard to be surprised when looking at the capabilities of semiconductor batteries, which offer volumetric energy density of up to 1000 watt-hours per liter (the best lithium-ion cells achieve 600 watt-hours per liter). However, what’s more important is gravimetric density, which is around 250 Wh/kg in NCM batteries and over twice as high in SSB batteries. With solid-state cells, the range of an EV would match that of a combustion engine car.
Additionally, semiconductor batteries do not have a liquid electrolyte, which is simply an organic solvent, a hydrocarbon that ignites rapidly in a fire. Nevertheless, solid-state batteries also have temperature monitoring systems to prevent cell overheating and degradation. ASSB batteries are also less prone to dendrite formation, which, after many charge cycles of a regular lithium-ion battery, causes power loss, short circuits, and, consequently, fires.
Dendrites are needle-like structures that form inside Li-ion cells on the anode. They originate from lithium crystals precipitating in the liquid electrolyte. The use of semiconductor conducting layers, which block the movement of electrons while allowing the passage of lithium ions thanks to the so-called Schottky barrier, prevents the accumulation of lithium crystals, thus preventing dendrite formation.
Unfortunately, semiconductor cells are subject to an increase in internal pressure during operation, which will complicate their construction and reduce the cost of such batteries to “only” $65 per kWh from around $150 per kWh in standard lithium-ion batteries (prices from 2023).
Silicon-Based Cells Will Need to Be Squeezed Hard
Several other startups, including those in Silicon Valley, are working on using silicon instead of graphite in battery anodes, which would provide even better performance than solid-state technology. Silicon batteries are impressive because they can charge up to 80% in just over 5 minutes and reach 98% charge in less than 10 minutes. Moreover, after 1000 cycles, their efficiency remains at 93%. The issue with silicon batteries is that they expand their volume threefold during operation. Therefore, test models have special stainless steel structures to limit the expansion to no more than 2% of the volume after 500 cycles. It seems that this solution is sufficient since Porsche announced the use of silicon batteries from 2024, and Mercedes-Benz plans to install these cells in luxury models starting in 2025.
Structural Batteries: An Integral Part of the Body or Building
Innovations in battery technology are not just about energy density or cost. The problem with modern cells is their large size, especially their weight (e.g., Tesla Model 3 batteries weigh up to 480 kg and, at an energy density of 150 Wh/kg, occupy a volume of 0.40 m3). From a design perspective, such a battery serves no purpose, so researchers at Chalmers University of Technology are working on structural batteries made of carbon fibers. Test models have a density of only 24 Wh/kg, but it is estimated that they can reach up to 75 Wh/kg. On one hand, this is still less than modern lithium-ion batteries, but on the other hand, structural cells have the strength similar to aluminum, making them not “useless mass” as they can serve as load-bearing elements in vehicle bodies or building structures.
Sodium Batteries Instead of Lithium: Solvents from Salt
Innovations in battery technology also aim to eliminate lithium from their construction, allowing the complete elimination of nickel, manganese, and cobalt. Extracting these materials is troublesome and has a carbon footprint. Therefore, instead of lithium, experimentation is being done with sodium. Sodium can be derived from desalination of water, making the production of such batteries more competitive on an industrial scale compared to the current reverse osmosis method.
Sodium batteries are being developed by companies like California-based Natron. They have announced that their cells have a lifespan over 10 times longer than modern Li-ion batteries. They can charge up to 99% in just 8 minutes, have a lifespan of over 50,000 cycles, and are exceptionally thermally stable. The downside is their significantly lower energy density compared to lithium-ion batteries. Nonetheless, sodium batteries are expected to become popular in micromobility vehicles, where low battery cost is more important than long range, and sodium-ion technology is particularly competitive in this regard.
Chinese “Condensed Batteries”
Chinese company CATL has announced the imminent start of mass production of a new “condensed battery” with an energy density of up to 500 Wh/kg. Moreover, batteries of this type charge very quickly. The manufacturer claims that a 10-minute charge of an electric vehicle equipped with such a battery will allow it to travel up to 400 km. The enormous energy density of CATL batteries would also enable their use in electric passenger airplanes.
Such remarkable parameters have been achieved through design changes, mainly involving the use of a new type of electrolyte and new cathode and anode materials. The innovative batteries from the Chinese manufacturer are expected to be used in the first electric vehicle models later this year. It is estimated that they will revolutionize the e-vehicle industry.
Fluoride Batteries: 8000 km Range and Months Without Smartphone Charging
Lithium can also be replaced with much cheaper fluoride, which could store up to 10 times more energy than contemporary Li-ion batteries. Fluoride batteries (FIB) are estimated to provide electric vehicles with a range of up to 8,000 km on a single charge and smartphones that don’t require charging for over a month. However, we currently know of few materials capable of conducting fluoride ions, although intense research is underway to discover them (ZnTiF6 shows promise).
Zinc and Aluminum-Sulfur Batteries
Another lithium alternative is zinc. The problem with zinc batteries is internal short circuits that can lead to fires, caused by dendrites, already known. A special chemical composition of the electrolyte is expected to reduce dendrite formation. The use of ethylene glycol and zinc tetrafluoroborate has produced a non-flammable electrolyte that maintains efficiency in temperatures ranging from -30°C to 40°C.
Also, aluminum-sulfur batteries may serve as an alternative to lithium cells. These batteries use inexpensive materials, and test samples charge to full capacity in less than one minute. Unfortunately, for full efficiency, they must be maintained at a temperature of up to 110°C. Nevertheless, during operation, they release heat that can be used for heating. Furthermore, theoretically, aluminum-sulfur batteries can achieve an energy density close to 1400 Wh/kg, five times more than the most efficient lithium-ion batteries. So, a Tesla Model 3 battery using aluminum-sulfur technology would weigh only 96 kg instead of 480 kg.
Carbon-Oxygen Battery: Houston, Do We Have a Problem?
There is also the promising use of carbon-oxygen cell technology. NASA designed it for converting the CO2-rich atmosphere of Mars into oxygen-rich air. When voltage is applied, the carbon-oxygen cell splits carbon dioxide into oxygen and carbon monoxide, generating current in the process. Such cells are expected to cost only $15 per kWh and offer a density of 740 Wh/l (for comparison, a Tesla Model 3 LR battery costs about $151 per kWh at a density of 247 Wh/). This makes them three times smaller than comparable Li-ion cells.
However, carbon-oxygen batteries can only maintain a charge for about 100 hours. After this time, the carbon monoxide and oxygen inside start to react with each other, leading to battery discharge. Therefore, this technology will not find use in EVs but may be employed in building energy storage systems for renewable energy installations.
Iron-Air Cells: Ideal for Renewable Energy?
Efficient batteries can also be built from iron oxide powder and water solution. These components are placed in a container connected to a hydrogen fuel cell. Passing current through the aqueous solution causes the release of oxygen from powdered iron oxide, which, in this case, means charging the battery. Oxygen dissolved in the water will soon turn into iron oxide, releasing hydrogen from water (this is what the battery discharge looks like), which will power the fuel cell, ultimately generating electricity.
Designers from Form Energy, who were supposed to build a working iron-air battery, claimed that its price per kWh is only $20 (in a typical Li-ion battery, the price is about $150 per kWh). However, these innovative cells are heavy and charge slowly. Therefore, instead of being used in EVs, they will most likely be used to build energy storage systems for renewable energy installations.
And while we’re on the topic, redox flow batteries also have great potential. They are also called flow batteries. They consist of tanks with electrolytes and a special membrane. Pumps force the flow of electrolytes on both sides of the membrane, which is responsible for electron transfer.
Thanks to this operating principle, the battery’s capacity depends on the amount of electrolyte, and its power on the number of cells. This allows for the construction of energy storage systems perfectly tailored to the user’s needs. In addition to easy scalability, flow batteries have a lifespan of about 20,000 cycles, which is over 20 years. Moreover, they provide higher fire safety, and the production and implementation costs are attractive, even though they have ten times lower energy density (12 – 40 Wh/kg) compared to Li-ion batteries.
Of course, redox flow batteries will not find application in micro-mobility vehicles or electric cars. Nevertheless, their use in energy storage systems will reduce the demand for Li-ion batteries, which will lower the cost of batteries produced using this technology.
I co-founded City Lion in December 2019. We manufacture and assemble battery packs for light electric vehicles. Within three years, we became the most popular European manufacturer of electric kick scooter batteries. Since 2023 we also produce electric bicycle batteries.