My watch list
my.chemeurope.com  
Login  

New materials for sustainable, low-cost batteries

02-May-2018

ETH Zürich / Kostiantyn Kravchyk

The researchers produced aluminium button cells in the laboratory. The battery case is made of stainless steel coated with titanium nitride on the inside to make it corrosion resistant.

seagul, pixabay.com, CC0

Electricity is also needed when the sun is not shining and no wind is blowing. Low-cost batteries are one way of temporarily storing energy from renewable sources.

A new conductor material and a new electrode material could pave the way for inexpensive batteries and therefore the large-scale storage of renewable energies.

The energy transition depends on technologies that allow the inexpensive temporary storage of electricity from renewable sources. A promising new candidate is aluminium batteries, which are made from cheap and abundant raw materials.

Scientists from ETH Zurich and Empa – led by Maksym Kovalenko, Professor of Functional Inorganic Materials – are among those involved in researching and developing batteries of this kind. The researchers have now identified two new materials that could bring about key advances in the development of aluminium batteries. The first is a corrosion-resistant material for the conductive parts of the battery; the second is a novel material for the battery’s positive pole that can be adapted to a wide range of technical requirements.

Aggressive electrolyte fluid

As the electrolyte fluid in aluminium batteries is extremely aggressive and corrodes stainless steel, and even gold and platinum, scientists are searching for corrosion-resistant materials for the conductive parts of these batteries. Kovalenko and his colleagues have found what they are looking for in titanium nitride, a ceramic material that exhibits sufficiently high conductivity. “This compound is made up of the highly abundant elements titanium and nitrogen, and it’s easy to manufacture,” explains Kovalenko.

The scientists have successfully made aluminium batteries with conductive parts made of titanium nitride in the laboratory. The material can easily be produced in the form of thin films, also as a coating over other materials such as polymer foils. Kovalenko believes it would also be possible to manufacture the conductors from a conventional metal and coat them with titanium nitride, or even to print conductive titanium nitride tracks on to plastic. “The potential applications of titanium nitride are not limited to aluminium batteries. The material could also be used in other types of batteries; for example, in those based on magnesium or sodium, or in high-voltage lithium-ion batteries,” says Kovalenko.

An alternative to graphite

The second new material can be used for the positive electrode (pole) of aluminium batteries. Whereas the negative electrode in these batteries is made of aluminium, the positive electrode is usually made of graphite. Now, Kovalenko and his team have found a new material that rivals graphite in terms of the amount of energy a battery is able to store. The material in question is polypyrene, a hydrocarbon with a chain-like (polymeric) molecular structure. In experiments, samples of the material – particularly those in which the molecular chains congregate in a disorderly manner – proved to be ideal. “A lot of space remains between the molecular chains. This allows the relatively large ions of the electrolyte fluid to penetrate and charge the electrode material easily,” Kovalenko explains.

One of the advantages of electrodes containing polypyrene is that scientists are able to influence their properties, such as the porosity. The material can therefore be adapted perfectly to the specific application. “In contrast, the graphite used at present is a mineral. From a chemical engineering perspective, it cannot be modified,” says Kovalenko.

As both titanium nitride and polypyrene are flexible materials, the researchers believe they are suitable for use in “pouch cells” (batteries enclosed in a flexible film).

Facts, background information, dossiers
  • new materials
  • electricity
  • renewable energy
  • energy storage
  • aluminium batteries
  • polypyrene
More about Empa
  • News

    A molecular bridge further

    Electronics built from molecules could open up new possibilities in the miniaturization of circuits in the future. Empa researchers, together with partners from Switzerland, the Netherlands, Israel, and  the UK, succeeded in solving a crucial detail in the realization of such circuit elemen ... more

    Self healing robots that "feel pain"

    Over the next three years, researchers from the Vrije Universiteit Brussel, University of Cambridge, École Supérieure de Physique et de Chimie Industrielles de la ville de Paris (ESPCI-Paris) and Empa will be working together with the Dutch Polymer manufacturer SupraPolix on the next genera ... more

    New record for flexible thin-film solar cells

    Flexible solar cell with unprecedented efficiency: The Empa Laboratory for Thin Films and Photovoltaics, headed by Ayodhya N. Tiwari, has broken its own record. The researchers improved the efficiency of energy conversion in CIGS solar cells on flexible polymer substrate to 20.8%. This is 0 ... more

  • Videos

    A water-based, rechargeable battery

    First step to produce a cheap aquous electrolyte for powerful rechargeable batteries: Seven grams of sodium FSI (precise name: sodium bis(fluorosulfonyl)imide) and one gram of water produce a clear saline solution with an electrochemical stability of up to 2.6 volts – twice as much as other ... more

More about ETH Zürich
  • News

    Using industrial waste as insulation for buildings

    ETH spinoff FenX transforms industrial waste into a porous foam suitable for building insulation. Unlike other sustainable materials used for the purpose, this type of insulation is non-flammable and inexpensive to produce. No sooner does one of the four young men come up with the idea than ... more

    Deep learning, prefabricated

    Self-driving cars, the automatic detection of cancer cells, online translation: deep learning makes it all possible. The ETH spin-off Mirage Technologies has developed a deep learning platform that aims to help start-ups and companies more quickly develop and optimise their products. The na ... more

    Mini-spectrometer: Smaller than a coin

    ETH researchers have developed a compact infrared spectrometer. It’s small enough to fit on a computer chip but can still open up interesting possibilities – in space and in everyday life. Nowadays, a mobile phone can do almost anything: take photos or video, send messages, determine its pr ... more

  • Videos

    Oxybromination of methane over vanadium phosphate

    ETH Zurich scientists have discovered a new catalyst that allows the easy conversion of natural gas constituents into precursors for the production of fuels or complex chemicals, such as polymers or pharmaceuticals. The new catalyst is extremely stable and results in fewer unwanted by-produ ... more

Your browser is not current. Microsoft Internet Explorer 6.0 does not support some functions on Chemie.DE