Open AccessSynthesis of Ni@NiSn Composite with High Lithium‐Ion Diffusion Coefficient for Fast‐Charging Lithium‐Ion Batteries
Author(s) -
Zhao Hong,
Chen Junxin,
Wei Weiwei,
Ke Shanming,
Zeng Xierong,
Chen Dongchu,
Lin Peng
Publication year - 2020
Publication title -
global challenges
Language(s) - English
Resource type - Journals
ISSN - 2056-6646
DOI - 10.1002/gch2.201900073
Subject(s) - anode , lithium (medication) , materials science , composite number , diffusion , ion , power density , cathode , graphite , electrode , chemical engineering , electrochemistry , composite material , chemistry , thermodynamics , power (physics) , medicine , physics , organic chemistry , engineering , endocrinology
To solve the problems of fast‐charging of lithium‐ion batteries in essence, development of new electrode materials with higher lithium‐ion diffusion coefficients is the key. In this work, a novel flower‐like Ni@SnNi structure is synthesized via a two‐step process design, which consists of the fabrication of Ni cores by spray pyrolysis followed by the formation of SnNi shells via a simple oxidation–reduction reaction. The obtained Ni@SnNi composite exhibits an initial capacity of ≈693 mA h g −1 and a reversible capacity of ≈570 mA h g −1 after 300 charge/discharge cycles at 0.5 C, and maintains 450 mA h g −1 even at a high rate of 3 C. Further, it is proved that a Ni@SnNi composite possesses high lithium‐ion diffusion coefficient (≈10 −8 ), which is much higher than those (≈10 −10 ) reported previously, which can be mainly attributed to the unique flower‐like Ni@SnNi structure. In addition, the full cell performance (Ni@SnNi‐9h/graphite vs LiCoO 2 ) with a capacity ratio of 1.13 (anode/cathode) is also tested. It is found that even at 2 C rate charging/discharging, the capacity retention at 100 cycles is still close to 89%. It means that Ni@SnNi‐9h is a promising anode additive for lithium‐ion batteries with high energy density and power density.