Batteries

Innovative materials for batteries

Batteries can store electric energy and release it when required. Unlike in supercapacitors, in some batteries, the energy can be preserved for months, or even years. Primary cells can only release energy, whereas secondary cells and accumulators could be recharged.

The material innovations at IOLITEC are mostly aimed at secondary cells.

 

Products:

We offer a series of standard electrolytes, ionic liquids, lithium salts and interesting electrode materials, like graphene or carbon nanotubes, for R&D use.

On request, we are also in the position to develop custom-made client specific solutions. The upscale up to 10 tonnes/year is also possible.

If you have any questions concerning this topic, please contact us. Our specialists will gladly provide you with more information on the topic.

Key-words:

  • Electrolytes for lithium-sulfur cells
  • Electrolytes for metal-air cells (Li, Zn, Al)
  • Polymer electrolytes (“Ionomers”)
  • Electrode materials (carbon nanotubes, graphene)
  • Filler materials

 

Electrolytes, conducting salts, electrode materials and additives

A Electrolytes

Electrolytes for batteries

In batteries, electrochemical processes are responsible for storage and release of electric energy (charging and discharging). To transport the electric charge between the electrodes, electrolytes are necessary. Electrolytes can be liquid, but polymer- or solid-state electrolytes exist.

Ionic liquids are interesting electrolytes for a series of electrochemical cells, due to their outstanding properties, like:

  • High electrochemical stability against reduction and oxidation (wide electrochemical window)
  • Electric conductivity: for pure ionic liquids lies at up to 27 mS/cm at 25 oC, for mixtures it can reach up to 70 mS/cm (Further information).
  • Thermal stability
  • Low vapour pressure
  • Low flammability

Many manufacturers are represented with their new developments on numerous cell types in market, but there is no unified state of the art technical design. That means, each particular electrode material will set very strict restrictions on specific properties of electrolytes, that should be combined with it. The additional demand for further development stems from the fact, that there are serious safety issues coupled to the use of some batteries.

IOLITEC works actively on the development of special electrolytes for use in different types of accumulators:

  • Lithium-sulfur
  • Lithium-metal
  • Metal-air (Zn, Al, Si, Li)
  • Redox-flow-batteries

For Lithium-ion-batteries, we offer a series of standard electrolytes (product series IoLiLyte LBE).

Should you have any questions on this topic, concerning applications or specific products, please contact us.

 

B Conducting salts

Lithium bis(trifluoromethylsulfonyl)imide

Nowadays, the most widely used conducting salt in lithium-ion batteries is lithium hexafluorophosphate (LiPF6). Lithium bis(trifluoromethylsulfonyl)amide (LiBTA), however is an interesting alternative. The BTA-anion exhibits better electrochemical stability and insensitive to hydrolysis, compared to LiPF6. No hydrofluoric acid (HF) can be formed from BTA-, as it only has covalently bound F. The conductivity of LiBTA is comparable to commonly used conducting salts, like LiClO4 and LiAsF6.

 

C Electrode materials

Carbon-nanotubes and graphene

Since not so long ago, the interest for carbon allotropes, like carbon nanotubes (CNT) and graphene had grown very strong and given the inspiration for numerous new research fields. Within the framework of European science support institutions, the research on graphene has its own dedicated program. CNT and graphene have the potential as new types of electrode materials. IOLITEC offers both of them as powders or dispersions in a variety of solvents.

 

D Filler materials

Filler materials, as additives to electrolytes, can perform various tasks. Composites, made from ionic liquids and nano materials, can improve the cyclability of batteries. Nanomaterials, e.g. barium titanate, find their use as fillers.

For more information, please contact us.

 

Text: Dr. Thomas J. S. Schubert, translation Dr. Svetlana Tsupova, IOLITEC GmbH, 2017