Evidence of covalent synergy in silicon-sulfur-graphene yielding highly efficient and long-life lithium-ion batteries.
Evidence of covalent synergy in silicon-sulfur-graphene yielding highly efficient and long-life lithium-ion batteries.
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DOI：
10.1038/ncomms9597
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发表时间：
2015-10-26
影响因子：
16.6
通讯作者：
Chen Z
中科院分区：
文献类型：
--
作者：
Hassan FM;Batmaz R;Li J;Wang X;Xiao X;Yu A;Chen Z
硅有可能彻底改变锂离子电池的储能能力，以满足下一代技术不断增长的电力需求。为了避免硅基阳极的运行稳定性问题，我们提出在设计过程中对电极结构进行协同的物理化学改变。这利用了硅纳米颗粒与硫掺杂石墨烯和环化聚丙烯腈的共价相互作用来提供坚固的纳米结构。这种分层结构稳定了固体电解质间相，导致在2ag - 1下进行2,275次循环，可逆容量超过1,000 mAh g - 1。此外，纳米结构的设计降低了电解质与电极的接触，不仅可以获得99.9%的高库仑效率，而且即使在3.4 mAh cm−2的高电极负载下也能保持高稳定性。优异的性能与简单、可扩展和无害的方法相结合，使该工艺成为锂离子电池技术的一个非常有前途的候选工艺。硅阳极在锂离子电池的发展中很有前途，但存在诸如体积膨胀和固体电解质界面形成等问题。在这里，作者报告了一种分层的硅-硫-石墨烯复合阳极，它减轻了导致高性能的问题。
Silicon has the potential to revolutionize the energy storage capacities of lithium-ion batteries to meet the ever increasing power demands of next generation technologies. To avoid the operational stability problems of silicon-based anodes, we propose synergistic physicochemical alteration of electrode structures during their design. This capitalizes on covalent interaction of Si nanoparticles with sulfur-doped graphene and with cyclized polyacrylonitrile to provide a robust nanoarchitecture. This hierarchical structure stabilized the solid electrolyte interphase leading to superior reversible capacity of over 1,000 mAh g−1 for 2,275 cycles at 2 A g−1. Furthermore, the nanoarchitectured design lowered the contact of the electrolyte to the electrode leading to not only high coulombic efficiency of 99.9% but also maintaining high stability even with high electrode loading associated with 3.4 mAh cm−2. The excellent performance combined with the simplistic, scalable and non-hazardous approach render the process as a very promising candidate for Li-ion battery technology. Silicon anodes are promising for lithium-ion battery development, but suffer from problems such as undesired volume expansion and solid-electrolyte interface formation. Here, the authors report a hierarchical silicon-sulfur-graphene composite anode which mitigates the problems leading to high performance.