3D Printing of Flexible Room-Temperature Liquid Metal Battery

TL;DR

This paper presents a novel 3D hybrid printing method to create flexible, soft, room-temperature liquid metal batteries using gallium and conductive gel, demonstrating stable discharge and potential for wearable electronics.

Contribution

It introduces a new 3D hybrid printing approach for fabricating flexible liquid metal batteries with customizable structures and demonstrates their practical application in wearable devices.

Findings

Batteries showed stable discharge properties.

Multi-cell batteries exhibited stair-step voltage decrease.

Flexible batteries successfully powered wearable devices.

Abstract

The entirely soft and transformable room-temperature liquid metal battery based on 3D hybrid printing was proposed and experimentally demonstrated. Liquid metal gallium and conductive gel were employed as the negative and positive electrode material, respectively. The discharge process of batteries with different structure, single-cell and multi-cell, were clarified. The results indicated that the obtained battery possessed rather stable and persisted discharge property, but the multi-cell battery presented stair-step decrease overtime. SEM and EDS images were obtained to evaluate the morphological change of the electrode during the discharge process, and the liquid metal was found to be easily exposed and active according to the solubility of the alkaline electrolyte to oxidized gallium. The successful 3D hybrid printing allowed different polymers, including PLA, ABS and TPU, to be precisely patterned in any required battery body structures, with liquid electrodes in appropriate specified positions. The flexibility and practicability of this new generation battery was illustrated through working devices. The present soft battery offers important power supply for future wearable and epidermal electronics.