A scalable snowballing strategy to construct uniform rGO-wrapped LiNi0.8Co0.1Mn0.1O2 with enhanced processability and electrochemical performance

Graphene is considered to be a desirable coating material to enhance the performance of Ni-rich cathodes. However, there are few facile methods to form a uniform graphene coating layer. Here, we propose a scalable snowballing strategy to prepare uniform rGO-wrapped LiNi0.8Co0.1Mn0.1O2 (PG-NCM) through convenient physical mixing with the help of a semi-conductive Perylene-3,4,9,10-tetracarboxylic dianhydride (PTCDA) layer, which can ensure the adhesion of graphene on the particle surface. Most importantly, verified by rheological tests, the PTCDA layer also plays a significant role in the homogeneous coating of graphene layer, suppressing the gelation phenomenon in slurry. While using PG-NCM as cathode materials, the synergistic effect of rGO nanosheets and PTCDA can provide better conductivity and more stable electrode-electrolyte interphase. In particular, the P1G1 -NCM (only 1.0 wt% additives) performs best among all samples. It reaches a high discharge capacity of 194.1 mAh g(-1) at 1C, 92.8% capacity retention (100 cycles, 1C) and enhanced rate performance (122.1 mAh g(-1) at 10C). With these results, this strategy is likely to be a practical technology in mass production of modified cathodes in Li-ion battery for large-scale production and cost-effective operability.

Automated summary

The study proposes a scalable snowballing strategy to prepare uniform rGO-coated cathode materials, with the addition of a PTCDA layer helping ensure the adhesion of graphene on the particle surface. The PG-NCM samples demonstrate superior conductivity and cycling stability, with the P1G1-NCM performing the best among all samples in terms of discharge capacity and capacity retention.