Invited: Na-Ion Battery Technologies: Present Status and Update

Na-ion batteries (sodium-ion batteries or SIB) that operate at ambient temperature present a great opportunity for the development of new energy storage systems that could be ideal for a myriad of applications.  Low cost, long-term stability and great abundance of Na are the major drivers that can move this technology forward.  Na batteries also could be positioned as a backup technology to Li-ion batteries, which would be of great value and insurance to the battery industry as one should not rely solely on one type of battery technology.  Energy densities of SIB can vary greatly depending on the voltage and capacity of the active materials.  While typically the energy densities of Na batteries are marginally lower compared to Li-ion batteries (about 30-50%), a host of new chemistry of compounds that are low cost with good performance are possible.  For example, a cathode material that consists solely of Na Fe, and Mn would be low cost and highly safe.  These elements are quite abundant and easily processed into active materials for the cathode using our new synthetic methods.  In addition low-cost carbon materials such as those that are derived from pyrolysis of plant matter can serve as a reversible low-cost anode host for Na cations which are stored within graphene regions and nano-cavity or nanopores.

In this talk, I will discuss the desirable characteristics of SIB technology by providing examples on electrochemical and battery cycling performance results from new materials utilized as electrodes  in SIBs.

Acknowledgement.  This work was supported by the U.S. Department of Energy, U.S. DOE-BES, under ContractNo.DE-AC02-06CH11357.