nn6b01626_si_001.pdf (1.19 MB)
Multilayer Approach for Advanced Hybrid Lithium Battery
journal contribution
posted on 2016-06-06, 00:00 authored by Jun Ming, Mengliu Li, Pushpendra Kumar, Lain-Jong LiConventional
intercalated rechargeable batteries have shown their
capacity limit, and the development of an alternative battery system
with higher capacity is strongly needed for sustainable electrical
vehicles and hand-held devices. Herein, we introduce a feasible and
scalable multilayer approach to fabricate a promising hybrid lithium
battery with superior capacity and multivoltage plateaus. A sulfur-rich
electrode (90 wt % S) is covered by a dual layer of graphite/Li4Ti5O12, where the active materials S
and Li4Ti5O12 can both take part
in redox reactions and thus deliver a high capacity of 572 mAh gcathode–1 (vs the total
mass of electrode) or 1866 mAh gs–1 (vs the mass of sulfur) at 0.1C (with the definition of 1C
= 1675 mA gs–1). The battery shows unique
voltage platforms at 2.35 and 2.1 V, contributed from S, and 1.55
V from Li4Ti5O12. A high rate capability
of 566 mAh gcathode–1 at 0.25C and 376
mAh gcathode–1 at 1C with durable cycle
ability over 100 cycles can be achieved. Operando Raman and electron
microscope analysis confirm that the graphite/Li4Ti5O12 layer slows the dissolution/migration of polysulfides,
thereby giving rise to a higher sulfur utilization and a slower capacity
decay. This advanced hybrid battery with a multilayer concept for
marrying different voltage plateaus from various electrode materials
opens a way of providing tunable capacity and multiple voltage platforms
for energy device applications.