Cheap, Rechargeable Water-based Battery

Cheap to produce

The researchers discovered that this saline solution displays an electrochemical stability of up to 2.6 volts – i.e. nearly twice as much as other aqueous electrolytes. The discovery could be the key to inexpensive, safe battery cells; inexpensive because, apart from anything else, the sodium FSI cells can be constructed more safely and thus more easily than the familiar lithium ion batteries.

Credit: Empa

The system has already withstood a series of charging and discharging cycles in the lab. Until now, however, the researchers have been testing the anodes and cathodes of their test battery separately – against a standard electrode as a partner. In the next step, the two half cells are to be combined into a single battery. Then additional charging and discharging cycles are scheduled.

Empa’s research activities on novel batteries for stationary electricity storage systems are embedded in the Swiss Competence Center for Heat and Electricity Storage (SCCER HaE), which coordinates research for new heat and electricity storage concepts on a national level and is led by the Paul Scherrer Institute (PSI). If the experiment succeeds, inexpensive water batteries will be within reach.

Contacts and sources:
Dr. Ruben-Simon Kühnel / Rainer Klose

Citation: A High-Voltage Aqueous Electrolyte for Sodium-Ion Batteries; RS Kühnel, D Reber, C Battaglia; ACS Energy Lett (2017), 2, 2005-2006, DOI: 10.1021/acsenergylett.7b00623