Polynitrosoarene Radical as an Efficient Cathode Material for Lithium-Ion Batteries

Organic
radical batteries (ORBs) with radical-branched polymers
as cathode materials represent a valuable alternative to meet the
continuously increasing demand on energy storage. However, the low
theoretical capacities of current radical-contained compounds strongly
hamper their practical applications. To address this issue, a chemically
robust polynitrosoarene (tris(4-nitrosophenyl)amine) with a pronounced
radical property is rationally designed as an efficient cathode for
ORBs. Its unique multi-nitroso structure displays remarkably reversible
charge/discharge capability and a superior capacity up to 300 mA h
g–1 (93% theoretical capacity) after 100 cycles
at 100 mA g–1 within a broad potential window of
1.3–4.3 V (vs Li+/Li). Moreover, the ultra-long
cycle life is also achieved at 1000 mA g–1 with
85% preservation of the capacity after 1000 cycles, making it the
best-reported organic radical cathode material for lithium-ion batteries.