The controlled release of active substance from one-dimensional inorganic nanocarrier for the stability enhancement of lithium batteries

Abstract

A controlled release system (CRS) is a successful treatment method in biomedical engineering that can deliver the therapeutic dosage of the drug over an extended period of time, with a single dose. Herein, we demonstrated an unusual approach of combining a CRS with an energy storage device to improve the electrochemical stability of lithium secondary battery with the therapeutic dosage. We have designed a sophisticated release system comprised of a model active substance (vinylene carbonate (VC)) and a naturally abundant one-dimensional inorganic nanocarrier (halloysite nanotube (HNT)). Its effectiveness in the energy storage device was verified using the lithium battery. The establishment of in vitro release measurement over time using gas chromatography in this study enabled the precise estimation of the release pattern. The VC encapsulated in the HNTs improved cycling stability of the LiNi0.6Mn0.2Co0.2O2/Li battery system than those with the simple VC introduction and the simple mixture of VC and HNTs by enhancing the interfacial stability of the battery electrodes with the progression of the charge-discharge cycles. The VC loaded HNT not only provides continuous release of VC for repairing SEI but also builds the robust organic-inorganic SEI layer (HNT incorporated poly (VC)). The proof-ofconcept of the proposed CRS is also investigated using another active substance (tris (trimethylsilyl) borate), where the compatibility with the battery is verified, and the cell performance is notably improved. This study proposes important insights regarding the use of the CRS in energy storage devices.