Investigating Liquid Metal Galinstan as a High Current Carrier and Its Interaction with Collector Electrodes

Abstract

In this work, we demonstrate the potential application of liquid metal galinstan as a means of carrying high currents between two collector electrodes. The room-temperature liquid metal was placed between two electrodes made either of stainless steel (SS) or of copper, where the electrical performance at applied currents as high as 250 A was monitored and found to be highly stable. The surface interaction between galinstan and the collector electrodes in the presence and absence of such high DC currents was also investigated. After 12 h of contact with Cu electrodes, analysis by X-ray diffraction and energy-dispersive X-ray experiments revealed the presence of Ga and Cu as well as evidence of very minor InSn phase separation from liquid galinstan to form a solid alloy. However, after the application of a DC current of 250 A for 12 h, extensive Cu−Ga alloy formation was observed in the form of CuGa 2 , as well as a more pronounced phase separation of the In and Sn components into islands of InSn. It was found that the slight temperature rise during electrical testing favored alloy formation but was not the origin of the phase separation of the In−Sn components. In contrast, analysis of the SS electrode after 24 h of an applied DC current of 250 A did not reveal any form of alloy formation. This work shows that the electrical performance of liquid metal galinstan is stable upon the application of high DC currents using two different contact materials even though the interaction with the contacts differs. In addition, this provides an interesting pathway that can be explored for alloy production using galinstan and Cu materials under the application of an applied current, which may have other uses apart from high-current-density carriers.

Applications of liquid metals in nanotechnology

“…110 The formation of Cu 2 Ga intermetallic was also reported in Galinstan sandwiched between two Cu current collectors and upon applying a high DC current. 112 Solidification of LM nanodroplets. Sonication of LM melts to form particles combined with subsequent solidification offers unique opportunities for synthesizing solid nanoparticles of post-transition metals and the observation of phenomenon such as supercooling (i.e.…”

Critical Review on the Physical Properties of Gallium-Based Liquid Metals and Selected Pathways for Their Alteration

“…Owing to practical and safety considerations, in recent years, researchers focused their attention toward gallium and its alloys, − as alloying gallium with metals, such as In and Sn, yields alloys with melting temperatures below room temperature (<25 °C) while their metallic nature is mostly maintained. Research efforts involving these alloys are directed to diverse research areas, , i.e., (soft) electronics, − liquid metal as catalyst, and reaction medium − and biomedicine (i.e., drug delivery). − This interest is fueled by the exceptional properties of the liquid metal, such as moldability due to the low viscosity of around 2 cP, electrical and thermal conductivity originating from their electron-rich cores, and low toxicity. , These properties endow devices based on liquid metal with advanced features, such as shape memory, self-healing, transience, controlled switching, − and high current carriers . First uses of gallium-based liquid metals in applications besides thermal management devices and thermometers have been established. , For example, it is employed in the hinges for foldable smartphones, i.e., the Huawei Mate X2, while liquid metals are anticipated to find application in e-skins and foldable wireless power transfer equipment. − In these applications, mainly two alloys are usedEGaIn and Galinstan.…”

Liquid Metal Composites with Enhanced Thermal Conductivity and Stability Using Molecular Thermal Linker

“…[13] Copper nanoparticles incorporated into GaInSn (66% Ga; 22%In; 16%Sn) via an oxide-free ultrasonic-assisted internalization process in HCl solution reached a high κ of 64.8 W m −1 K −1 . [14] In these efforts involving mixing Ga-based liquid metal with fillers of high thermal conductivity, gallium, however, can react with many metals such as copper, [20,21] silver, [22] aluminum, [23] and iron, [16] to form intermetallic compounds (IMCs) due to its reactive nature. For example, in the eutectic gallium indium-copper (EGaIn-Cu) composite system, the reaction between copper and gallium produces CuGa 2 IMCs.…”