Accumulator batteries are designed to power mobile electric equipment and vehicles safely in all kinds of applications. This means that all material and chemicals used should be as non-toxic and flame-retardant as possible, in particular also with regard to the electrolytes used. Electrolytes are to enable charge equalization.
State of the art
In the lithium ion accumulator batteries now used more and more frequently, the positively charged lithium ions balance out the electron movement necessary for charging or discharging. The higher the mobility of lithium ions, the more powerful is the battery. Many of the electrolytes currently available and considered safe have the drawback of allowing only limited mobility of the lithium ions. This is true in particular of solid electrolytes and ionic liquids.
KIT scientists of the Institute for Applied Materials - Materials Studies (IAM-WK) developed a new electrolyte which achieves good mobility of the lithium ions and is flame-retardant at the same time. The new electrolyte solution consists of a mix of a carbonate ring, such as ethylene carbonate, and a sulphone derivative, such as dimethylsulphone. The molecules are relatively small, hardly impeding movement of the lithium ions.
The electrolyte developed at the KIT is clearly more flame-retardant than many known liquid electrolytes. The flash point of the new electrolyte mix is above 140°C. In addition, the liquid has comparatively low viscosity and an extremely high boiling point. A high boiling point is an advantage because it can avoid gas formation and bursting of the accumulator battery at higher temperatures. The electrolyte solution can be used in a temperature range between approximately 0 and at least 60°C.
Options for companies
Scientists at the KIT have tested the electrolyte successfully in button cells and small pouch cells and are now looking for partners for further development and practical use.
Your contact person for this offer
Dr. Aude Pélisson-Schecker,
Karlsruhe Institute of Technology (KIT)
Innovation Manager Energy, Innovation and Relations Management (IRM)
Phone: +49 721 608-25335