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Chinese Scientists Improves Oxide-Peroxide Conversion in Lithium Ion Battery

Metal News - Published on Tue, 15 Oct 2019

Image Source: physicsworld.com
A new high-energy density and stable lithium-ion battery that works by reversible oxide-peroxide conversion could help in the development of improved sealed battery technologies. This is the new result from a team of researchers in Japan and China who have designed an oxygen-free cell in which the Li2O to Li2O2 reaction can take place. These batteries work thanks to the redox reaction between O2 and lithium peroxide, Li2O2. One of the main hurdles hindering their practical application, however, is that they require O2 gas as the active species. This needs to be supplied by bulky O2 storage or gas purification devices. To overcome this problem, and the so-called O2 crossover and electrolyte volatilization in these batteries, researchers led by Mr Haoshen Zhou of the National Institute of Advanced Industrial Science and Technology and Nanjing University in China have now designed an O2-free sealed environment for the Li2O to Li2O2 reaction.

Mr Zhou and colleagues did this by embedding Li2O nanoparticles into an iridium-reduced graphene oxide (Ir-rGO) catalytic substrate to successfully control the charging potential within a small region of the device and avoid the unwanted phenomenon of over-polarization.

The researchers also restrained two other serious problems that beset sealed redox systems: the irreversible evolution of O2 and the production of superoxide (an aggressive and dangerous product). They did this by controlling the degree of the electrochemical reaction and its cycling depth and thus succeeded in producing a reversible capacity for the device of 400 mAh/g, a value that fares well when compared to other cathode candidates for Li-ion batteries.

The result is a high-energy density (1090 Wh/kg), high energy efficiency (a mere 0.12 V polarization potential), rechargeable Li-ion battery technology that is stable over 2000 cycles with 99.5% coulombic efficiency.

The researchers, reporting their work in Nature Catalysis 10.1038/s41929-019-0362-z, say they are now looking for more effective catalysts to further boost the reversible capacity region in their device and enhance the reaction kinetics.

Source :

Posted By : Rabi Wangkhem on Tue, 15 Oct 2019
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