After solid and sand, liquid batteries could solve the problems of the electric car. we would like to believe
Published by The team in News the 12/08/2022 at 10:26
One of the most interesting alternatives to lithium-ion batteries are liquid flow batteries , which have been developed for years but never produced.
So far, the start-up Influit Energy (born under the aegis of the Institute of Technology at the University of Illinois in the USA) has just announced that it is very close to achieving this thanks to its non-flammable fast-charging technology , which promises to be "up to 23% more efficient than lithium batteries, at half the price."
Its operation from the so-called "nanoelectrofuels" (NEF, for its acronym in English) is designed both to power electric cars and other means of transport such as planes. NASA and the US Armed Forces collaborated in its development.
"The world's first electric, safe and rechargeable fuel".
The work of the Influit Energy team began in 2009 as a pure exercise in basic science in a humble laboratory that has already surpassed them.
More than a decade later, the facilities and team led by researcher and company CEO, John Katsoudas , have evolved so much that they have created "the world's first safe, rechargeable electric fuel".
And that sounds as promising as it sounds, though, as often happens with technology that promises to be game-changing, there are "buts."
The truth is that flow batteries or "liquid batteries" are nothing new. These normally start from two liquid chemicals which are pumped into two containers or tanks separated by an ion exchange membrane to create an electrical current, although they tend to have a low energy density.
Generally speaking, this is because it is only possible to dissolve a certain amount of the battery material before it begins to settle to the bottom of the tank, rendering fluids useless.
Mainly for this reason, flow batteries had not passed the development stage or been applied in relevant projects so far.
Influit Energy scientists claim to have solved this problem by using solid nanoparticles of battery material (specifically, active metal oxide) suspended rather than dissolved in their base fluid.
By the so-called random Brownian motion , it is achieved that these tiny particles do not settle to the bottom.
“We have created a new type of flow battery that is based on a composite material that we have invented, which is a high density nanofluid in which the nanoparticles are active materials for the battery, which we have called nanoelectrofuel, or NEF “, he added, explains John Katsoudas .
In this way, the NEF would function as a fuel that can be extracted from the battery and replaced with already charged fuel: and not just for the same purpose.
It can be reused in different vehicles and is not flammable
One of the three founders of Influit Energy, who is also chief operating officer and director of research and professor of chemistry at the University of Illinois, Elena Timofeeva, details this very interesting point of her technology:
“The unique format of NEF Flow Batteries allows the same fluids to be used in different devices. This means that the fluid, charged from renewable energy sources or the electrical grid, can be used to quickly refuel vehicles or for stationary storage and other portable applications.
Thus, according to the scientist, the evacuated fluid can be returned to a refueling station to be recharged when needed, or recharged inside the vehicle or device in which it is plugged directly into a power source. . It can also be recycled.
Additionally, Katsoudas claims that the nanoparticles are surface-modified to prevent clumping and reduce the viscosity of the battery solution, “to the point where the NEFs flow more or less like oil through an engine .”
According to data published by Influit Energy, its flow batteries are non-flammable, can operate at temperatures between -40°C and 80°C , and have "23% higher energy density by volume than lithium-ion batteries. ion.", between 350 and 550 Wh/l with a cost of almost half that of these.
Influit is developing not only liquid batteries, but also the fuel cell-like devices needed to extract energy, as well as a fuel management system that keeps fluids separated and retains spent fuel for recycling.
In the first version of the flow battery, baptized with the commercial name of DARPA, the project had the support of NASA , which financed the development of fast charging systems.
For its part, the US Armed Forces helped develop the nanoparticle system, and the US government itself contributed more than $10 million in funding. And it is that these flow batteries could be used to power future military electric vehicles.
On paper, these liquid batteries have many advantages over lithium-ion batteries beyond the higher energy density they promise.
Among the main ones, we note that they are neither flammable nor explosive, since if the liquids accidentally mix, nothing happens except a slight increase in temperature of a few degrees.
Additionally, by not using rare materials or raw materials , they are cheaper to produce.
Likewise, they are easy to quickly recharge and can also be recycled through a streamlined process. However, one of the most important questions remains to be clarified: its longevity, which has not been revealed by the company.
Moreover, there is still a long way to go before reaching the final stage of mass production, starting with a correctly sized installation and more personnel. They are already working on it, but in the meantime, the outlook is encouraging for Influit.
Researchers are already testing what would be the second generation of DARPA to see if it is viable. According to them, "it will offer an energy density four to five times higher than conventional lithium batteries (up to 550-750 Wh/kg) for a third of its cost".
