Flower-petal Grain Layered LiNi_(89)Co_(0.10)Sb_(0.01)O_2 as Next-generation Cathode Material

摘要

In layered oxide cathodes for lithium-ion batteries, nickel provides high capacity but compromises stability. Although much progress has been made in upsetting this trade-off, the stability of Ni-rich cathodes is not yet adequate to satisfy the expectations of commercial batteries. Here, a layered Li[Ni_(0.89)Co_(0.10)Sb_(0.01)]O_2 cathode material, which overcomes the instabilities associated with highly Ni-rich cathodes to deliver excellent capacity retention, is reported. This cathode shows a significantly enhanced resistance to performance deterioration and microcrack propagation compared to the more conventional Li[Ni_(0.885)Co_(0.10)Al_(0.015)]O_2 material. Furthermore, it delivers more capacity than its counterpart despite the same nickel content. The robustness of the material arises from the ordering of the grains into a dense flower-petal arrangement, which collectively preserves the coherency of the particle. Through extensive cross-sectional imaging and chemical mapping, a correlation between microcracks and electrolyte infiltration into the particle is demonstrated.