Rechargeable lithium air batteries are a next-generation technology: Theoretically they might be much lighter¹ and offer better performance than current lithium ion batteries. However, currently they run out of steam after only a few charging cycles. Researchers at the Technical University of Munich (TUM) and the Forschungszentrum Jülich have now investigated the processes and discovered a possible culprit: highly reactive singlet oxygen, which is released when the batteries are charged. A trimming diet is in order: Cell phones still bulge² from jacket pockets and laptop computers continue to overstrain shoulder muscles. To blame are primarily the batteries: The ubiquitous lithium ion batteries need heavy electrodes made of transition metal oxides.

 

Light-weight alternatives are thus sought after. "One of the most promising⁴ approaches is the lithium air battery in which the lithium cobalt oxide³ cathode is replaced by carbon particles," explains Johannes Wandt, doctoral candidate and member of Prof. Hubert Gasteiger's team in the Department of Technical Electrochemistry at TUM.

 

"The theoretical energy density⁵ of these new rechargeable batteries is significantly higher than that of traditional lithium ion batteries:" Unfortunately, the technology is not yet ready for everyday use because rechargeable lithium air batteries have only a very short lifetime: After only a few charging cycles the carbon electrode becomes corroded⁶ and the electrolytic fluid decomposes⁷. "The problem was that no one knew exactly why," remarks Wandt.

点击收听单词发音