Source: The Conversation – Canada – By Alicia M. Battaglia, Postdoctoral Researcher, Department of Mechanical & Industrial Engineering, University of Toronto
As the world races to electrify everything from cars to cities, the demand for high-performance, long-lasting batteries is soaring. But the uncomfortable truth is this: many of the batteries powering our “green” technologies aren’t as green as we might think.
Most commercial batteries rely on fluorinated polymer binders to hold them together, such as polyvinylidene fluoride. These materials perform well — they’re chemically stable, resistant to heat and very durable. But they come with a hidden environmental price.
Fluorinated polymers are derived from fluorine-containing chemicals that don’t easily degrade, releasing persistent pollutants called PFAS (per- and polyfluoroalkyl substances) during their production and disposal. Once they enter the environment, PFAS can remain in water, soil and even human tissue for hundreds of years, earning them the nickname “forever chemicals.”
We’ve justified their use because they increase the lifespan and performance of batteries. But if the clean energy transition relies on materials that pollute, degrade ecosystems and persist in the environment for years, is it really sustainable?
As a graduate student, I spent years thinking about how to make batteries cleaner — not just in how they operate, but in how they’re made. That search led me somewhere unexpected: the ocean.
Why binders are important
(Unsplash/CHUTTERSNAP)
Every rechargeable battery has three essential components: two electrodes separated by a liquid electrolyte that allows charged atoms (ions) to flow between them. When you charge a battery, the ions move from one electrode to the other, storing energy.
When you use the battery, the charged atoms flow back to their original side, releasing that stored energy to power your phone, car or the grid.
Each electrode is a mixture of three parts: an active material that stores and releases energy, a conductive additive that helps electrons move and a binder that holds everything together.
The binder acts like glue, keeping particles in place and preventing them from dissolving during use. Without it, a battery would be unable to hold a charge after only a few uses.
Lessons from the sea
Many marine organisms have evolved in remarkable ways to attach themselves to wet, slippery surfaces. Mussels, barnacles, sandcastle worms and octopuses produce natural adhesives to stick to rocks, ship hulls and coral in turbulent water — conditions that would defeat most synthetic glues.
For mussels, the secret lies in molecules called catechols. These molecules contain a unique amino acid in their sticky proteins that helps them form strong bonds with surfaces and hardens almost instantly when exposed to oxygen. This chemistry has already inspired synthetic adhesives used to seal wounds, repair tendons and create coatings that stick to metal or glass underwater.
Building on this idea, I began exploring a related molecule called gallol. Like catechol in mussels, gallol is used by marine plants and algae to cling to wet surfaces. Its chemical structure is very similar to catechol, but it contains an extra functional group that makes it even more adhesive and versatile. It can form multiple types of strong, durable and reversible bonds — properties that make it an excellent battery binder.
(Unsplash/Manu Mateo)
A greener solution
Working with Prof. Dwight S. Seferos at the University of Toronto, we developed a polymer binder based on gallol chemistry and paired it with zinc, a safer and more abundant metal than lithium. Unlike lithium, zinc is non-flammable and easier to source sustainably, making it ideal for large-scale applications.
The results were remarkable. Our gallol-based zinc batteries maintained 52 per cent higher energy efficiency after 8,000 charge-discharge cycles compared to conventional batteries that use fluorinated binders. In practical terms, that means longer-lasting devices, fewer replacements and a smaller environmental footprint.
Our findings are proof that performance and sustainability can go hand-in-hand. Many in industry might still view “green” and “effective” as competing priorities, with sustainability an afterthought. That logic is backwards.
We can’t build a truly clean energy future using polluting materials. For too long, the battery industry has focused on performance at any cost, even if that cost includes toxic waste, hard-to-recycle materials and unsustainable and unethical mining practices. The next generation of technologies must be sustainable by design, built from sources are renewable, biodegradable and circular.
Nature has been running efficient, self-renewing systems for billions of years. Mussels, shellfish and seaweeds build materials that are strong, flexible and biodegradable. No waste and no forever chemicals. It’s time we started paying attention.
The ocean holds more than beauty and biodiversity; it may also hold the blueprint for the future of energy storage. But realizing that future requires a cultural shift in science, one that rewards innovation that heals, not just innovation that performs.
We don’t need to sacrifice progress to protect the planet. We just need to design with the planet in mind.
This research was supported by the National Sciences and Engineering Research Council of Canada, the Canadian Foundation for Innovation, and the Ontario Research Fund. Alicia M. Battaglia received funding from the Ontario Graduate Scholarship Program.
– ref. Lessons from the sea: Nature shows us how to get ‘forever chemicals’ out of batteries – https://theconversation.com/lessons-from-the-sea-nature-shows-us-how-to-get-forever-chemicals-out-of-batteries-273098