High-Energy-Density Li-Ion Battery Reaching Full Charge in 12 min

초록

The continuous expansion of the electric vehicle (EV) market is driving the demand for high-energy-density batteries using Ni-rich cathodes. However, the operation of Ni-rich cathodes under extreme-fast-charging (XFC) conditions compromises their structural integrity, resulting in rapid capacity fading; realizing Ni-rich cathodes operable under XFC conditions while maximizing energy density and long-term cycling performance is challenging. This study introduces a Li[Ni0.92Co0.06Al0.01Nb0.01]O2 (Nb-NCA93) cathode with a high energy density of 869 Wh kg-1. The presence of Nb in the Nb-NCA93 cathode induces the grain refinement of its secondary particles, alleviating internal stress and preventing heterogeneity of Li concentration during cycling. A resulting full-cell reaches full charge within 12 min and retains 85.3% of its initial capacity after 1000 cycles (cycled at full depth of discharge). In addition, the Nb-NCA93 cathode generates limited heat under XFC conditions due to its refined microstructure.

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