Zhao Hong, Chen Junxin, Wei Weiwei, Ke Shanming, Zeng Xierong, Chen Dongchu, Lin Peng
Shenzhen Key Laboratory of Special Functional Materials and Shenzhen Engineering Laboratory for Advanced Technology of Ceramics College of Materials Science and Engineering Shenzhen University Shenzhen 518060 P. R. China.
School of Materials Science and Energy Engineering Foshan University Foshan 528000 China.
Glob Chall. 2019 Nov 22;4(3):1900073. doi: 10.1002/gch2.201900073. eCollection 2020 Mar.
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 and a reversible capacity of ≈570 mA h g after 300 charge/discharge cycles at 0.5 C, and maintains 450 mA h g even at a high rate of 3 C. Further, it is proved that a Ni@SnNi composite possesses high lithium-ion diffusion coefficient (≈10), which is much higher than those (≈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) 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.
为从本质上解决锂离子电池快速充电的问题，开发具有更高锂离子扩散系数的新型电极材料是关键。在这项工作中，通过两步工艺设计合成了一种新型的花状Ni@SnNi结构，该工艺包括通过喷雾热解制备Ni核，然后通过简单的氧化还原反应形成SnNi壳。所获得的Ni@SnNi复合材料在0.5 C下经过300次充/放电循环后，初始容量约为693 mA h g，可逆容量约为570 mA h g，即使在3 C的高倍率下也能保持450 mA h g。此外，证明了Ni@SnNi复合材料具有高锂离子扩散系数（≈10），这比先前报道的那些（≈10）要高得多，这主要归因于独特的花状Ni@SnNi结构。此外，还测试了容量比为1.13（阳极/阴极）的全电池性能（Ni@SnNi-9h/石墨对LiCoO）。发现即使在2 C倍率下充/放电，100次循环后的容量保持率仍接近89%。这意味着Ni@SnNi-9h是一种有前途的用于锂离子电池的阳极添加剂，具有高能量密度和功率密度。
