July 13, 2024

A Breakthrough in Rechargeable Magnesium Batteries: 3D Magnesiophilic Substrate Enables Planar Electroplating/Stripping of Magnesium Metal Anode

Rechargeable magnesium batteries are emerging as a promising alternative to lithium-ion batteries due to the superior properties of magnesium metal anodes. Magnesium (Mg) metal offers high volumetric capacity, abundant resources, environmental friendliness, and a resistance to dendrite growth. However, challenges such as dendrite formation under extreme electroplating conditions have hindered the practical application of magnesium batteries.

They discovered that using a practical polyolefin separator caused short-circuits in coin cells, even at low current densities. To address this challenge, the researchers developed a layer-by-layer planar growth model to suppress short-circuits and proposed the design strategy of a 3D magnesiophilic substrate for achieving planar magnesium electroplating/stripping behavior.

The findings of this study were published in ACS Energy Letters on December 4.

Previous studies have shown that magnesium growth is uniform and dense when the current density is below 5 mAh/cm2. However, the use of practical polyolefin separators with thin thicknesses can lead to internal short-circuits in coin cells during low-current charging and discharging.

To better understand this abnormal short-circuit behavior, the researchers proposed an island-growth model for magnesium deposits based on electrochemical tests and microscopic morphology observation. By adjusting the lattice mismatch parameters and surface energy of the substrate, the researchers successfully achieved layer-by-layer planar growth of magnesium deposits, effectively solving the issue of abnormal short-circuits.

In their research, the scientists utilized a magnesiophilic 3D substrate (Ni(OH)2@CC) with low lattice mismatch and high surface energy properties as an electroplating substrate. This substrate not only enabled the reversible electroplating/stripping process but also matched with a high-load Mo6S8 cathode (30 mg/cm2).

By addressing the short-circuit phenomenon caused by abnormal non-dendritic electroplating behavior in rechargeable magnesium batteries (RMBs) and proposing validated solutions, this study takes a significant step towards the practical application of magnesium metal anodes.

The use of magnesium metal anodes in rechargeable batteries has the potential to revolutionize the energy storage industry. With their high volumetric capacity, sustainable resources, and environmental friendliness, magnesium batteries could offer a more efficient and sustainable energy storage solution. However, dendrite formation has been a major obstacle in utilizing magnesium as an anode material.

The breakthrough achieved by the researchers at the Qingdao Institute of Bioenergy and Bioprocess Technology of the Chinese Academy of Sciences addresses this challenge by developing a 3D magnesiophilic substrate. This substrate enables planar electroplating and stripping of magnesium metal, eliminating the problem of dendrite growth.

The key to this breakthrough lies in the design of the magnesiophilic substrate. By carefully adjusting the lattice mismatch parameters and surface energy of the substrate, the researchers were able to promote the layer-by-layer planar growth of magnesium deposits. This ensures a uniform and dense deposition of magnesium, reducing the risk of short-circuits.

The practical implications of this research are significant. By enabling planar electroplating and stripping of magnesium metal, rechargeable magnesium batteries can now operate at higher efficiency and reliability. The use of magnesium as an anode material can contribute to the development of more sustainable and environmentally friendly energy storage solutions.

Further research and development in this area are necessary to fully commercialize rechargeable magnesium batteries. However, this breakthrough brings us one step closer to harnessing the full potential of magnesium as a superior anode material. As the demand for efficient and sustainable energy storage continues to grow, innovations like these pave the way for a greener future.

1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it