Researchers have invented nanowire-based battery material that can be recharged hundreds of thousands of times, moving us closer to a battery that would never require replacement. The breakthrough work could lead to commercial batteries with greatly lengthened lifespans for computers, smartphones, appliances, cars and spacecraft.
They coated a gold nanowire in a manganese dioxide shell and encasing the assembly in an electrolyte made of a Plexiglas-like gel. The combination is reliable and resistant to failure.
They demonstrated reversible cycle stability for up to 200 000 cycles with 94–96% average Coulombic efficiency for symmetrical δ-MnO2 nanowire capacitors operating across a 1.2 V voltage window in a poly(methyl methacrylate) (PMMA) gel electrolyte. The nanowires investigated here have a [email protected]δ-MnO2 [email protected] architecture in which a central gold nanowire current collector is surrounded by an electrodeposited layer of δ-MnO2 that has a thickness of between 143 and 300 nm. Identical capacitors operating in the absence of PMMA (propylene carbonate (PC), 1.0 M LiClO4) show dramatically reduced cycle stabilities ranging from 2000 to 8000 cycles. In the liquid PC electrolyte, the δ-MnO2 shell fractures, delaminates, and separates from the gold nanowire current collector. These deleterious processes are not observed in the PMMA electrolyte.
SOURCES- University california Irvine, Energy Letters