Compact 3D Copper with Uniform Porous Structure Derived by Electrochemical Dealloying as Dendrite-Free Lithium Metal Anode Current Collector
Compact 3D Copper with Uniform Porous Structure Derived by Electrochemical Dealloying as Dendrite-Free Lithium Metal Anode Current Collector
复制标题
通过电化学脱合金获得具有均匀多孔结构的致密 3D 铜作为无枝晶锂金属阳极集电器
DOI：
10.1002/aenm.201800266
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发表时间：
2018-07-05
影响因子：
27.8
通讯作者：
Lu, Jun
中科院分区：
文献类型：
--
作者：
Zhao, Heng;Lei, Danni;Lu, Jun
锂（Li）金属阳极Li金属电池的发展面临着巨大的挑战，如Li枝晶生长失控，Li镀/剥过程中体积变化大，导致容量衰减严重，安全隐患高。三维多孔铜（Cu）集流体作为Li沉积的主体可以有效地解决这些问题。然而，构建均匀致密的3D多孔Cu结构仍然是一个巨大的挑战。在此，报道了一种用于铜锌（Zn）合金的电化学蚀刻方法，以精确地雕刻具有均匀、光滑和致密的多孔网络的3D Cu结构。这种连续结构赋予3D Cu优异的机械性能和高导电性。具有大的内表面积的均匀且光滑的孔确保了用于均匀的Li金属沉积和容纳的良好分散的电流密度。形成了光滑稳定的固体电解质界面，同时有效抑制了Li枝晶和死Li。在1 mA·h·cm（-2）的Li镀/剥离容量和1 mA·cm（-2）的电流密度下，Li金属阳极构思的3D Cu集流体可以稳定地循环400 h。Li@3D Cu|| LiFePO4全电池具有优异的循环和倍率性能。电化学去合金化是构建用于无枝晶Li金属阳极的3D Cu集流体的稳健方法。
The development of lithium (Li) metal anodes Li metal batteries faces huge challenges such as uncontrolled Li dendrite growth and large volume change during Li plating/stripping, resulting in severe capacity decay and high safety hazards. A 3D porous copper (Cu) current collector as a host for Li deposition can effectively settle these problems. However, constructing a uniform and compact 3D porous Cu structure is still an enormous challenge. Herein, an electrochemical etching method for Cu-Zinc (Zn) alloy is reported to precisely engrave a 3D Cu structure with uniform, smooth, and compact porous network. Such a continuous structure endows 3D Cu excellent mechanical properties and high electrical conductivity. The uniform and smooth pores with a large internal surface area ensures well dispersed current density for homogeneous Li metal deposition and accommodation. A smooth and stable solid electrolyte interphase is formed and meanwhile Li dendrites and dead Li are effectively suppressed. The Li metal anode conceived 3D Cu current collector can stably cycle for 400 h under an Li plating/stripping capacity of 1 mA h cm(-2) and a current density of 1 mA cm(-2). The Li@3D Cu||LiFePO4 full cells present excellent cycling and rate performances. The electrochemical dealloying is a robust method to construct 3D Cu current collectors for dendrite-free Li metal anodes.