Are Tomorrow's Fuel Cells Made of Paper? This Engineer Thinks So - OZY | A Modern Media Company

Are Tomorrow's Fuel Cells Made of Paper? This Engineer Thinks So

Are Tomorrow's Fuel Cells Made of Paper? This Engineer Thinks So

By Pablo Esparza Altuna


Because his fuel cells are cheaper, easier and cleaner than conventional batteries.

By Pablo Esparza Altuna

Where others might look at substances like urine, blood and sweat and cringe, Juan Pablo Esquivel sees untapped sources of energy. Not for powering large engines but rather to produce small amounts of electricity that could play a vital role in the burgeoning telemedicine market. Today Esquivel, a 35-year-old electronics engineer, is developing miniature paper-based fuel cells at the National Centre of Microelectronics (CNM) at the Autonomous University of Barcelona (AUB), with an eye toward using them to power disposable diagnostic devices.

As we stroll the corridors of CNM, Esquivel explains the difference between typical lithium or alkaline batteries and what he’s developing: Unlike what you might use in a flashlight or computer keyboard, fuel cells require a supply of energy from an electrochemical reaction to produce electricity. This type of power source has been tested to generate energy for cars and mobile phones, but Esquivel, who started his career at the Monterrey Institute of Technology in his native Mexico, is among the first to do this work on a micro scale.

A lithium battery, a fuelium battery and a power pad photo pablo esparza

A lithium battery, a Fuelium battery and a power pad.

Source Pablo Esparza

Not only does his approach open up the range of possible uses for these tiny fuel cells, but it also sidesteps the environmental impact from regular batteries. “We develop small, nontoxic, inexpensive fuel cells and batteries that don’t need to be recycled and could be thrown away with no ecological impact,” he explains with a Mexican accent laced with Iberian Spanish expressions.


Born in Guadalajara, Esquivel moved to Barcelona in 2005, having fallen in love with the city while doing a college backpack tour through Europe. When it was time to apply to Ph.D. programs, he was intrigued by the work being done at CNM, among the most advanced labs of its kind in Southern Europe. It proved to be the right fit: In 2013, he was named by MIT to the list of the 10 most innovative Mexican researchers under 35.

“Esquivel is like Cristiano Ronaldo, and, like Ronaldo, he’s playing for an excellent team. That’s why he gets results,” jokes Antonio Martínez, a professor at the Polytechnic University of Madrid.

They stopped focusing on hydrogen, methanol and ethanol as the only energy sources for fuel cells and started looking at bodily fluids.

The Mexican researcher confesses that he’s long been obsessed with “making things cheaper, simpler and easier.” Once his team had developed the paper-based batteries, they wanted to find a universal, everyday use for them. So Esquivel and Neus Sabaté, his thesis adviser and “scientific soul mate,” shelved their academic journals and turned instead to considering what people and the market needed.

They focused on portable, disposable diagnostic tests, such as for pregnancy, glucose and infectious diseases, that use small amounts of energy. Those devices, they noticed, rely on lithium button batteries to supply the energy necessary to analyze the samples and to display the results. But, in contrast to watches or remote controls, single-use diagnosis tests get discarded after having used less than 1 percent of their batteries’ charge — an “ecological aberration,” in Esquivel’s words.

Juan pablo esquivel holding a paper based battery photo pablo esparza (1)

Juan Pablo Esquivel holding a paper-based battery, an eco-friendly power source for single-use applications.

Source Pablo Esparza

That was the moment that Esquivel and his colleagues connected the dots: “What if we used the samples [of saliva or blood] to feed a small fuel cell that would generate the electricity needed for the analysis and to display the results?” They stopped focusing on hydrogen, methanol and ethanol as the only energy sources for fuel cells and started looking at bodily fluids as materials capable of triggering an electrochemical reaction — and generating electricity.

Digging further, they reached two important conclusions: First, they could build their power sources using paper as the base material to transport the fluids by capillary action; and second, these power sources could be integrated, thanks to printed electronics technology, with other electronic components such as sensors and display screens to produce self-powered devices.

In 2015, with patent in hand, Esquivel, Sabaté and Sergi Gassó — who joined as a business partner — founded Fuelium, with seed money from their personal savings, funding from the Repsol Foundation startup accelerator program and grants from the Spanish government and the European Commission. The company aims to translate the outcome from their lab work for the portable diagnostic tests market, a sector Esquivel values at $1.8 billion. While he sees a clear path to market for Fuelium, he acknowledges that breaking in will be a heavy lift: Getting out of the lab is “a big challenge for a quite disruptive technology like ours,” he says. Two years since launch, Fuelium has grown to a staff of five and signed its first contract. 

Emmanuel Delamarche, manager of precision diagnostics at IBM Research in Zurich, agrees that portable devices have become a “very hot area,” both in scientific and economic terms, with a trending away from remote, centralized labs and toward portable diagnostic tools that deliver faster results. “Eighty percent of the world’s population needs this kind of technology because they don’t live next to a clinical lab,” Delamarche explains.

Sabaté, who has worked with Esquivel for 12 years, is impressed by her partner’s creative mind and willingness to experiment. “He never says no to an idea,” she says, “no matter how crazy it is.”

Crazy or not, Esquivel is already working on a new idea: developing what he calls the “power pad,” which he hopes will lead to the first fully biodegradable paper-based battery. It’s an ambitious play for a “tiny, sustainable and clean” source of energy, he admits — but it’s a project, he adds with a smile, that lets him “have fun on the way.”


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