In the unit’s current form, it provides limited power, though it is expected to see rapid improvements.

A proton battery is a rapid charging form of energy storage that is currently only powerful enough to operate a small device such as a flashlight or personal fan for a handful of minutes. However, with the help of hydrogen and a considerable amount of research, that technology is moving forward rapidly, and many believe that it could be a vital component to decarbonization.

Researchers have been combining the best features of this experimental energy storage using hydrogen.

Proton batteries are made from entirely renewable resources, which helps to overcome many of the challenges of conventional units, which require precious metals such as lithium and cobalt. Those metals are not only very expensive but are in limited supply and are environmentally intensive to obtain.

The proton battery is rapid charging and operate mainly on water and activated carbon. RMIT University researchers in Melbourne, Australia developed this battery, which, despite its current small amount of power storage, is just as tiny as lithium-ion.

The researchers have partnered with an Italian company in the hopes of developing a prototype large enough for home storage. They expect that they can accomplish this goal within about two years.

As small as the proton battery is, the researchers expect that its evolution with hydrogen is highly promising.

“The proton battery has evolved from our attempts to get a simpler, more efficient, hydrogen-based energy storage system,” said Professor John Andrews, lead researcher for the project and renewable energy specialist at RMIT University.

Conventional green hydrogen fuel systems use electrolyzers which split water molecules into H2 and O2, hydrogen and oxygen gases. However, within that reaction, there are certain other stages, such as when hydrogen atoms are initially converted into positively charged hydrogen ions (H+). It is after that point that they become H2 as they pair up.

From there, the H2 can be burned or reacted with oxygen again, providing energy with only water and a bit of heat as the emissions.

“The basic reaction that we’re using is similar to what is used in a hydrogen fuel cell-based energy storage system,” said Andrews. “So we start with water, we split that in a cell that’s very like an electrolyser that’s used in a hydrogen system, and then you get protons, H+.”

Hydrogen is well suited to a proton battery

A hydrogen atom typically has a single positively charged proton as well as a negatively charged electron. By taking the electron away, what is left is an H+ ion, which is a proton.

“Protons are then passed through a membrane, same as in a fuel cell, but they then enter a porous carbon electrode that is negatively charged. The protons are then stored within this carbon matrix,” explained Andrews. “In your normal hydrogen system, those protons combine in pairs with electrons to give you hydrogen gas, and then you have to store the hydrogen gas.”

That said, there isn’t any gas in a proton battery. “We’re storing protons directly in the carbon electrode, which is part of the cell,” pointed out Andrews.

As such, when power is needed, the protons react with the oxygen in the air, providing an energy release and generating water.

Removing a middle step

“We’ve cut out that step of producing and having to store hydrogen gas. The protons are stored directly, which is safer, and it is much more energy efficient,” said Andrews.

Activated carbon is the material used as the electrode to store those protons. Andrews explained that “Activated carbon is a carbon that’s been hollowed out, and it’s got a very high internal surface area. It’s got lots of pores and channels connecting the pores.”

Activated carbon is also a highly renewable material, as it can be obtained for the proton battery from a spectrum of different feedstocks.

“You can make it from wood and charcoal, you can make it from wheat straw, you can make it from coal,” said Andrews. “We’re quite optimistic about the eventual economics of the device. Because the primary sources are very abundant and very cheap.”

Frequently Asked Questions about Proton Batteries

What is a proton battery? A proton battery is a type of energy storage device that uses carbon and water, making it an environmentally-friendly alternative to conventional batteries that are based on lithium and rare earth elements. The battery works by splitting water molecules during charging to generate protons, which bond to a carbon electrode. Source: Futurism & RMIT

How does a proton battery work? The proton battery works similarly to a reversible fuel cell. It accepts water while charging, splits out positively-charged hydrogen ions (protons), and stores them directly in the carbon electrode. During discharging, the protons react with oxygen in the air, releasing energy and generating water. Source: New Atlas & Cosmos Magazine

Why are proton batteries considered environmentally friendly? Proton batteries are made from renewable resources like water and carbon. They do not require precious metals such as lithium and cobalt, which are expensive, in limited supply, and environmentally intensive to obtain. Source: The Driven & Science Direct

What are the potential applications of proton batteries? Currently, the power provided by a proton battery is limited, but rapid improvements are expected. In their current form, proton batteries can power small devices for a limited amount of time. However, researchers anticipate that proton batteries could soon be used for home energy storage. Source: Allied Market Research

Who is developing proton batteries? Researchers at RMIT University in Melbourne, Australia, are leading the development of proton batteries. They have partnered with an Italian company to develop a prototype large enough for home storage. Source: RMIT

What makes proton batteries different from hydrogen fuel cells? While both systems start with the splitting of water molecules, in a proton battery, the protons are stored directly in the carbon electrode rather than being combined with electrons to produce hydrogen gas. This eliminates the need to store hydrogen gas, making the process safer and more energy efficient. Source: Cosmos Magazine

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