Abstract
The energy storage performance of lithium-ion batteries (LIBs) depends on the electrode capacity and electrode/cell design parameters, which have previously been addressed separately, leading to a failure in practical implementation. Here, we show how conformal graphene (Gr) coating on Ni-rich oxides enables the fabrication of highly packed cathodes containing a high content of active material (~99 wt%) without conventional conducting agents. With 99 wt% LiNi(0.8)Co(0.15)Al(0.05)O(2) (NCA) and electrode density of ~4.3 g cm(-3), the Gr-coated NCA cathode delivers a high areal capacity, ~5.4 mAh cm(-2) (~38% increase) and high volumetric capacity, ~863 mAh cm(-3) (~34% increase) at a current rate of 0.2 C (~1.1 mA cm(-2)); this surpasses the bare electrode approaching a commercial level of electrode setting (96 wt% NCA; ~3.3 g cm(-3)). Our findings offer a combinatorial avenue for materials engineering and electrode design toward advanced LIB cathodes.