Sep 24, 2013

Molten Air - A new, highest energy class of rechargeable batteries with up to 4.5 times the energy capacity of lithium air batteries

Where are the high energy capacity, cost effective batteries urgently needed for a range of medical, transportation and power generation devices, including in greenhouse gas reduction applications such as overcoming the battery driven "range anxiety" of electric vehicles, and increased capacity energy storage for the electric grid? This study introduces the principles of a new class of batteries, rechargeable molten air batteries, and several battery chemistry examples are demonstrated. The new battery class uses a molten electrolyte, are quasi-reversible (rechargeable), and have amongst the highest intrinsic battery electric energy storage capacities. Three examples of the new batteries are demonstrated. These are the iron, carbon and VB2 molten air batteries with respective intrinsic volumetric energy capacities of 10,000, 19,000 and 27,000 Wh liter-1. These compare favorably to the intrinsic capacity of the well known lithium air battery (6,200 Wh liter-1) due to the latter's single electron transfer and low density limits.

Higher energy capacity, cost effective batteries are needed for a range of electronic, transportation and greenhouse gas reduction power generation devices. Needed greenhouse gas battery reduction applications include overcoming the battery driven "range anxiety" of electric vehicles, and increased capacity energy storage for the electric grid.


The molten iron air battery. Charging (in this case from dissolved LiFeO2, dissolving 1:1 Li2O to Fe2
O3) forms a thick iron layer on the cathode as described in the text. Rights side: Discharge polarization (following electrochemical charge to form iron) of the air and iron electrodes in 730°C molten lithium carbonate with LiFeO2.


Read more »