Another Solvay Efficient Solution to change the world
Third Solvay solution to receive the Solar Impulse Efficient Solution label
The World Alliance for Efficient Solutions created by the Solar Impulse Foundation has recognized the value of Solef® PVDF as a sustainable (and profitable) solution for a cleaner environment. Applied in batteries, this fluorinated polymer improves the performance and durability of electric vehicles.
Following AgRHO® S-BoostTM, a seed booster, and SOLVAir®, an industrial exhaust cleaning solution, Solvay is proud to have yet another of its products, Solef® PVDF, recognized as environmentally and economically sustainable by the Solar Impulse Foundation and its stringent scrutiny, all over the course of a few months. The Foundation created by Swiss pilot Bertrand Piccard, who famously flew around the world using nothing but solar energy aboard the Solar Impulse, is hard at work identifying 1,000 “Efficient Solutions” with a proven environmental impact and business viability.
The idea is to prove that the technological solutions humanity needs already exist to address the challenge of preserving the health of our planet, and that they can even be profitable. Solvay is fully on board with this philosophy, and having its solutions thusly evaluated complements the Group’s own Sustainable Portfolio Management assessment methodology.
Providing higher battery energy density, safety and power
So how does Solef® PVDF, a fluorinated semi-crystalline thermoplastic, contribute to making the planet greener? By improving the performance of lithium-ion batteries, specifically those of electric cars, it contributes to the development of emissions-free mobility. Leveraging Solvay’s long-standing expertise in fluorinated chemistry and polymerization, Solef® PVDF is used in a variety of applications such as oil & gas, semiconductors, water filtration membranes, architectural coatings and photovoltaics. In batteries, adding it in the formulation of electrodes and separator coating results in higher battery density, safety and power: they enable higher voltages, resist high temperatures (which is key in the case of electric vehicle batteries), they charge faster and they become fire-resistant.
Coincidentally, the recognition of the environmental value of this application of Solef® PVDF in batteries comes precisely at the same time as the 2019 Nobel Prize for chemistry was awarded to the scientists who developed lithium-ion batteries in the 1980s: Akira Yoshino (Japan) and John B. Goodenough and M. Stanley Whittingham (USA). Batteries, a key activity for Solvay as a Group, are in the news now more than ever!
Applied in the batteries of electric vehicles, Solef® PVDF is so resistant that it will last as long as the car, if not longer!”
Less polymer for more battery power
To get into the specifics, Solvay’s product distinguished by the Solar Impulse Alliance is a grade of Solef® PVDF that improves the adhesion of the polymer in binders. “To make the formulation as efficient as possible, you need to add the smallest possible quantity of fluorinated polymer”, explains Thierry Baert, Sales Development Manager, Alternative Energy at Solvay’s Specialty Polymers Business Unit. “You put in less product and the efficiency of the battery increases: it’s a very unique situation.”
In fact, he goes on to explain that the amount of PVDF in binders has already been divided by ten over the last twenty years, “but at the same time, the market has grown tremendously, and so has the value of our product,” he adds. The next step is to continue reducing that proportion by making the polymer even more adhesive.
High performance materials to fly around the planet
This new grade was developed in the mid-2000s, right around the time Solvay started working with the Solar Impulse project to help develop its batteries – as flying around the world with solar power required batteries that just didn’t exist so far.
“It was good timing. Solar Impulse was like a flying laboratory that served to validate the use of PVDF in very high performance conditions,” says Richard Thommeret, Solvay’s Science & Innovation Communication Director. “And today, with the Solar Impulse Alliance recognizing Solef® PVDF as an Efficient Solution, it’s like we’ve come full circle. And it also demonstrates, a few years down the road, that these developments were relevant.”
In addition to being very resistant, Solef® PVDF is also very stable: “Contrary to other polymers that degrade fast in batteries under the effect of the typically high cell voltage of Li-Ion batteries, Solef® can durably resist this aggressive environment,” explains Thierry. “It will last as long as the car, if not longer!” This is one of the things that make it a promising material for the development of future generations of solid-state batteries…