Many see electric vehicles (EVs) as the future of sustainable transportation. Effectively large batteries on wheels, EVs are considered a necessary alternative to gas-guzzling, carbon dioxide-emitting combustion engines.
However, like anything in life, there are only really comprises rather than complete solutions. This is certainly the case with EVs.
First, they tend to have limited ranges compared to combustion-engined vehicles, and their charging infrastructure tends to focus on major population centers. Not ideal for long-distance trips.
The batteries they use, for example, require large quantities of critical minerals like lithium, cobalt, and nickel. These materials can have significant environmental impacts, and their mining and refining are often linked to ethical concerns, especially in parts of the world where labor practices are questionable.
As for the batteries, unless directly charged from renewable sources, most EV charging is done via the national grid, which in many countries is still heavily reliant on fossil fuels. However, an increasing number of grids are incorporating renewable energy sources, and some EV owners directly charge their vehicles using solar or other green energy solutions.
But another technology, flow batteries, might be the solution we’ve all been looking for.
Let’s find out how.
What is a flow battery?
A flow battery, also known as a reduction-oxidation (Redox) flow battery, is an electrochemical cell that uses two moving liquid electrolytes to generate electricity. The battery is designed so that the two special liquids flow adjacent to one another, separated by a thin membrane.
Ion transfer occurs across the cell membrane, accompanied by current flow through an external circuit, while the liquids circulate in their respective spaces. The liquids required are stored in separate tanks until required.
Flow batteries have existed for some time, but earlier versions had low energy density, making them impractical for cars. However, recent advancements in the technology have improved energy density, making it increasingly viable for long-duration energy storage and potentially for electric vehicles.
Various types of flow batteries, including inorganic and organic forms, have been demonstrated. Flow battery design can be classified into full flow, semi-flow, and membranesless variants.
The fundamental difference between conventional and flow batteries is that energy is stored in the electrode material in conventional batteries, while in flow batteries, it is stored in the electrolyte.
Flow batteries offer advantages for electric cars, such as non-toxicity, non-flammability, longer range, and quicker refueling than charging lithium-ion batteries (a common concern with EVs). Recent improvements in energy density have made flow batteries viable for long-duration energy storage in stationary applications.
However, until recently, making them small enough to power a car had been a pipedream. Small-scale flow batteries are already emerging for home energy storage, and one Swiss company, nanoFlowcell, is taking the lead in this interesting new potential technology for electric vehicles.
Flow battery EVs over the horizon?
The concept has already left the drawing board. Companies like nanoFlowcell have already developed and tested miniature flow cells for vehicles.
In 2019, the company unveiled its QUANTiNO test EV, which used an earlier version of its flow battery technology. This test model proved the concept and could rack up over 10,000 hours of driving over almost 220,000 miles (357,275 km) with little to no degradation of the flow-battery parts.
However, these claims have limited independent validation and, while promising, the technology is still in its early stages.
To this end, the latest model of the QUANTiNO was unveiled in December 2023. According to reports, this EV can travel up to 1,242 miles (2,000 km) on a single “tank” of flow battery liquids. The company has also announced that it is beginning research and development in the US from its newly minted New York subsidiary.
This model held the liquids in separate tanks in the car’s trunk. Since then, nanoFlowcell has refined the technology so that the tanks can be integrated into the body of the EV.
Moreover, flow battery-powered EVs are only part of the plan, which also includes wristwatches, drones, energy storage, and robotics. However, as Clean Technica reports, EVs are the main thrust of their current research and development.
The US branch, in particular, will be responsible for planning the series production of the QUANT E-models and the construction of a large-scale bi-ION production facility.
bi-ION: the future of extended-range EVs?
bi-ION is the company’s trademark for the special liquids used in its flow batteries. This is, in effect, a special kind of salty water.
According to the company, bi-ION is produced by mixing specially purified water and metallic and non-metallic salts. To this mixture, another top-secret molecule is added that is said to be a “specially designed energy carrier.”
“The bi-ION electrolyte solution has a power density comparable to modern lithium-ion batteries but with an energy density that is five times higher. bi-ION is the perfect energy solution for environmentally friendly and sustainable electric drives as well as for clean energy stationary and mobile applications,” nanoFlowcell explains.
“The flow cells and the bi-ION® electrolyte solution work without the need for precious or rare earth metals,” the company adds.
The system’s emissions consist of water atomized and released as vapor. When driving, the electrolyte tanks are emptied like those in conventional combustion engine vehicles.
Refuels are similar to a normal car
Refueling them would be the same as refueling a standard gasoline or diesel vehicle. The company estimates that if widely adopted, its technology could cut carbon dioxide emissions by as much as 19,250 megatons a year.
That is around a 75 percent reduction from the present day—an ambitious vision and certainly worth exploring.
While this is an ambitious and speculative vision, it is dependent on widespread adoption, continued technological advances, and a global shift toward renewable energy.
The company has also developed its vehicle-to-grid (V2G) system, allowing users to use their EVs effectively as portable home generators. This is an interesting bonus.
And that is your lot for today.
Flow batteries, like those in development by nanoFlowcell, are undoubtedly attractive, but will they be able to muscle their way into the EV market? While their performance, endurance, and longevity are certainly an improvement on most existing EVs, that is for sure.
But will that be enough for consumers to take an interest? Time and tide will tell.
