Liquid Metal-Elastomer Seals for Stretchable Organic Electrolyte-Based Lithium-Ion Batteries

Rapid progresses concerning wearable electronics call for stretchable batteries. Owing to the merits of high energy density and wide operating voltage range, organic electrolyte-based lithium-ion batteries (LIBs) take a large proportion in the powering markets. Due to the high sensitivity to moisture and oxygen, it is difficult to obtain long-term reliable stretchable organic electrolyte-based LIBs when they are directly exposed to the air. Benefiting from the outstanding gas impermeability of liquid metal (LM) and relatively good barrier properties for reactive acid gas molecules by polyisobutylene (PIB), an LM-PIB seal is demonstrated for organic electrolyte-based LIBs. In the seal, LM can prevent the inward permeation of oxygen and water vapor, and PIB can block the outward permeation of hydrolysis acid generated from the side reactions during the operation of the organic electrolyte-based LIBs, which helps prevent the detrimental interaction between the hydrolysis acid and LM. A specific capacity of over 120 mAh g-1 is achieved and the battery shows consistent electrochemical performances under multiple deformations. This study offers a different design approach for long-term operation of stretchable organic electrolyte-based LIBs. Stable seals for stretchable organic electrolyte-based lithium-ion batteries (LIBs) are demonstrated by the integration of liquid metal (excellent hermetic properties and low Young's modulus) and polyisobutylene (good barrier properties against acid gases). The seal can block the inward permeation of the ambient moisture/oxygen and the outward permeation of reactive gases from the inner cell of organic electrolyte-based battery system. With such seal, the organic electrolyte based LIB exhibits good stretchability and operation stability.image