24-May-2022 - Technische Universität München

Mini-fuel cell generates electricity using the body's sugar

Glucose energy source for medicinal implants and sensors

Glucose is the most important energy source in the human body. Scientists at the Technical University of Munich (TUM) and the Massachusetts Institute of Technology (MIT) now want to use the body's sugar as an energy source for medicinal implants. They have developed a glucose fuel cell which converts sugar into electricity.

Medicinal implants such as sensors for measuring vital functions, electrodes for Deep Brain Stimulation in treating Parkinson's disease and cardiac pacemakers all require power sources which are as reliable and as small as possible. But there are limits to how far battery size can be reduced, since batteries require a certain volume in order to be able to store energy.

A research team led by Jennifer Rupp, Professor for the chemistry of solid-state electrolytes at TUM and MIT's Dr. Philipp Simons have now developed a glucose fuel cell which is only 400 nanometers thick – one hundredth of the diameter of a human hair. "Instead of using a battery, which accounts for 90 percent of an implant's volume, our device can be mounted as a thin film on a silicon chip or perhaps in the future even on the surface of the implant itself," says Rupp.

Ceramics replace plastic

The glucose fuel cell consists of a cathode and an anode as well as an electrolyte layer. Glucose from the body is converted to gluconic acid at the anode, releasing protons. The electrolyte conducts these protons through the fuel cell to the cathode, where they recombinate with air to form water molecules. The electrons flow through an external electric circuit which can power an electronic device.

The idea of using glucose fuel cells as a power source is not new: Previous devices used a plastic electrolyte layer. "Since plastic materials are not compatible with common production processes in the semiconductor industry, it is difficult to apply them to silicon chips, which are state of the art in medical implants. Hard materials are needed for this," Simons explains. Another disadvantage of the plastic-based electrolytes: The polymers which made up the plastic were sometimes damaged when sterilizing the implants.

Consequently the researchers used ceramic electrolytes for their new fuel cell. The ceramic they chose is easy to miniaturize and integrate on a silicon chip and is bio-compatible. The material can also withstand high temperatures.

Highest power density ever

The team produced 150 of the glucose fuel cells on a chip, with each cell only 400 nanometers thick and about 300 micrometers wide. The researchers successfully mounted the cells on silicon wafers, proving that the devices could be combined with a conventional semiconductor material. Then they let a glucose solution flow over the wafer.

They found that many of the cells generated a peak voltage of approximately 80 millivolts, enough to power for example sensors and many other electronic devices for implants. Given the minuscule size of each cell, this is the highest-ever power density of any glucose fuel cell design to date.

"This is the first time that the proton conduction in electro-ceramic materials has successfully been used in converting glucose into electricity," says Rupp. In a next step the research team wants to help bring the discovery to long-term practical application.

Facts, background information, dossiers
More about TUM
  • News

    On the road to the super-battery

    A research team led by the Technical University of Munich (TUM) has taken an in-depth look at the internal workings of batteries during charging and discharging. Their findings may help optimize charging processes. When an electric car is being charged, the charge indicator moves quickly at ... more

    When quantum particles fly like bees

    A quantum system consisting of only 51 charged atoms can assume more than two quadrillion different states. Calculating the system's behavior is a piece of cake for a quantum simulator. Yet even with today's supercomputers it is almost impossible to verify the result. A research team from t ... more

    Bright, stable, and easy to recycle lighting

    A low-cost and easy-to-manufacture lighting technology can be made with light-emitting electrochemical cells. Such cells are thin-film electronic and ionic devices that generate light after a low voltage is applied. Researchers at the Technical University of Munich (TUM) and the University ... more

  • Videos

    Scientists pair up two stars from the world of chemistry

    Many scientists consider graphene to be a wonder material. Now, a team of researchers at the Technical University of Munich (TUM) has succeeded in linking graphene with another important chemical group, the porphyrins. These new hybrid structures could also be used in the field of molecular ... more

More about MIT
  • News

    New light-powered catalysts could aid in manufacturing

    Chemical reactions that are driven by light offer a powerful tool for chemists who are designing new ways to manufacture pharmaceuticals and other useful compounds. Harnessing this light energy requires photoredox catalysts, which can absorb light and transfer the energy to a chemical react ... more

    Light may increase performance of fuel cells and lithium-ion batteries

    Lithium-ion batteries, fuel cells and many other devices depend on the high mobility of ions in order to work properly. But there a large number of obstacles to such mobility. A research team led by Jennifer L. M. Rupp of the Technical University of Munich (TUM) and Harry L. Tuller of the M ... more

    Frozen light in graphene

    Scientists from University of Regensburg, Massachusetts Institute of Technology, Moscow institute of Physics and Technology, and University of Kansas have discovered abnormally strong light absorption in graphene. The effect arises from the conversion of ordinary electromagnetic waves into ... more

  • Videos

    Movable microplatform floating on droplets

    A new approach to microelectromechanical systems (MEMS), developed by a team of researchers at MIT, could offer a new way of making movable parts with no solid connections between the pieces, potentially eliminating a major source of wear and failure. Video: Melanie Gonick/MIT more

    Plant-to-human communication

    MIT engineers have transformed spinach plants into sensors that can detect explosives and wirelessly relay that information to a handheld device similar to a smartphone. Video: Melanie Gonick/MITInfrared/fluorescent images: Min Hao Wong more

    Particles attract across long distances

    MIT researchers have found a new kind of long-range interaction between particles, in a liquid medium, that is based entirely on their motions. Video: Melanie Gonick/MIT more