Nanodiamonds suppress the growth of lithium dendrites

Nature Communications, Aug 2017

Lithium metal has been regarded as the future anode material for high-energy-density rechargeable batteries due to its favorable combination of negative electrochemical potential and high theoretical capacity. However, uncontrolled lithium deposition during lithium plating/stripping results in low Coulombic efficiency and severe safety hazards. Herein, we report that nanodiamonds work as an electrolyte additive to co-deposit with lithium ions and produce dendrite-free lithium deposits. First-principles calculations indicate that lithium prefers to adsorb onto nanodiamond surfaces with a low diffusion energy barrier, leading to uniformly deposited lithium arrays. The uniform lithium deposition morphology renders enhanced electrochemical cycling performance. The nanodiamond-modified electrolyte can lead to a stable cycling of lithium | lithium symmetrical cells up to 150 and 200 h at 2.0 and 1.0 mA cm–2, respectively. The nanodiamond co-deposition can significantly alter the lithium plating behavior, affording a promising route to suppress lithium dendrite growth in lithium metal-based batteries.

A PDF file should load here. If you do not see its contents the file may be temporarily unavailable at the journal website or you do not have a PDF plug-in installed and enabled in your browser.

Alternatively, you can download the file locally and open with any standalone PDF reader:

https://www.nature.com/articles/s41467-017-00519-2.pdf

Nanodiamonds suppress the growth of lithium dendrites

Abstract Lithium metal has been regarded as the future anode material for high-energy-density rechargeable batteries due to its favorable combination of negative electrochemical potential and high theoretical capacity. However, uncontrolled lithium deposition during lithium plating/stripping results in low Coulombic efficiency and severe safety hazards. Herein, we report that nanodiamonds work as an electrolyte additive to co-deposit with lithium ions and produce dendrite-free lithium deposits. First-principles calculations indicate that lithium prefers to adsorb onto nanodiamond surfaces with a low diffusion energy barrier, leading to uniformly deposited lithium arrays. The uniform lithium deposition morphology renders enhanced electrochemical cycling performance. The nanodiamond-modified electrolyte can lead to a stable cycling of lithium | lithium symmetrical cells up to 150 and 200 h at 2.0 and 1.0 mA cm–2, respectively. The nanodiamond co-deposition can significantly alter the lithium plating behavior, affording a promising route to suppress lithium dendrite growth in lithium metal-based batteries. Introduction Lithium (Li), the lightest metal, delivers a theoretical specific capacity of 3860 mAh g−1, nearly ten times higher than the traditional graphite anode (372 mAh g−1) in Li ion batteries (LIBs). The Li+/Li redox couple provides the most negative potential of −3.04 V (vs. standard hydrogen electrode), rendering a high working voltage in a full cell. These features deliver a high-energy density when the Li metal anode is paired with the high-capacity cathode material to form a full cell. As a result, rechargeable Li metal-based batteries (LMBs), such as Li-sulfur (Li-S) and Li-oxygen (Li-O2) batteries are regarded as promising candidates for high-energy-density storage1, 2. However, LMBs may develop dangerous Li dendrites, limiting their practical applications due to the following reasons3,4,5,6,7: (1) dendritic deposition of Li can electronically connect the cathode and anode, resulting in the cell short circuiting, thermal runaway, and failure with possible explosion or fire; (2) Li dendrites increase the contact area, facilitating side reactions between the Li metal and organic electrolyte. The reaction products electronically isolate the Li metal from the conductive matrix, thus resulting in inactive (dead) Li, and, consequently, low Coulombic efficiency, large polarization, and poor lifespan of the LMB8,9,10. Strategies to suppress Li dendrites can be divided into four categories: (1) solid/gel polymer electrolyte11,12,13, (2) Li metal/organic electrolyte interface modifications14,15,16,17,18,19,20, (3) weakening space charge on the anode surface8, 21, 22, and (4) anode matrix design23,24,25,26. While extensive studies have been conducted to explore methods to suppress Li dendrite growth, investigations into the mechanism of nucleation and growth of Li metal are limited27. Recently, Cui and co-workers investigated the nucleation potential of Li on various current collectors. Their results indicated a substrate-dependent nucleation behavior, as they achieved selective deposition of Li metal onto a chosen substrate28. By designing a nanocapsule structure of hollow carbon spheres with nanoparticle seeds inside, they enabled Li metal to plate the inside of the hollow carbon spheres. However, this strategy simply conceals Li deposits (or dendrites) inside a carbon sphere, and does not fully solve the dendrite problem. It should be noted that dendrite growth is not unique to the field of rechargeable metal batteries. In the conventional electroplating industry, numerous efforts have also been devoted to suppressing the dendritic growth and achieving the uniform deposition of metal coatings, such as Ni and Co29, 30. A nanodiamond-involved co-deposition technique by adding nanodiamond particles into the electroplating bath, has been well-developed and applied in industrial electroplating to achieve the deposition of uniform metal films31, 32. This technique involves the co-deposition of metal ions and nanodiamond particles, and the underlying mechanism has been thoroughly investigated33: (1) The metal ions adsorb on the surface of nanodiamond and are carried to the electrode surface by convection of electrolyte in the electrolytic bath and electric field; (2) Metal ions accept electrons and are reduced to metal deposits on the electrode surface. The adsorbed nanodiamond particles are either released into the solution or captured by the growing metal film. Co-deposition using nanodiamond as an additive leads to the uniform deposition of metal films, and improves the hardness, lubricity, and wear resistance of the deposited film34, 35. Hence, a major improvement in properties can be achieved with minimal capture of nanodiamond particles, simply due to modification of the deposition conditions with nanoparticles at the solid-electrolyte interface36. Inspired by this co-deposition strategy, we p (...truncated)


This is a preview of a remote PDF: https://www.nature.com/articles/s41467-017-00519-2.pdf

Xin-Bing Cheng, Meng-Qiang Zhao, Chi Chen, Amanda Pentecost, Kathleen Maleski, Tyler Mathis, Xue-Qiang Zhang, Qiang Zhang, Jianjun Jiang, Yury Gogotsi. Nanodiamonds suppress the growth of lithium dendrites, Nature Communications, 2017, Issue: 8, DOI: 10.1038/s41467-017-00519-2