Significant progress has been made in increasing the specific energy and cycle life of silicon (Si) based Li-ion batteries (Si-LIBs). However, calendar life of the state-of-the-art Si-LIBs is still less than two years, which is far less than the 10-year life-time required for electrical vehicle applications  One reason for limited calendar life in these batteries is due to the mechanical stress on the SEI layer formed on Si anode which exhibits large volume change during charge/discharge process.  In our recent work, two approaches have been used to overcome breakdown and continuous growth of SEI layers.  One approach is to design a micron sized porous Si with nanopores coated with conductive carbon  by pitch coating method. This approach will generate significant amount of nanopores imbedded inside of micron sized Si to absorb most of Si expansion and minimize mechanical stress exert on Si particles and associated SEI layers.  The second approach is to improve the mechanical strength and reusability of SEI layers using localized high concentration electrolytes (LHCEs).  These LHCEs can lead to the formation of SEI layers that are rich in inorganic components robust against the mechanical failure caused by the large volume changes. As a result, the overall performance of the Si based LIBs are greatly improved.   The electrolytes have been tailored for different applications, including high voltage (&lt; 4.45 V), high temperature (&gt; 45°C) and high rate (&gt; 2C) applications.  The combination of these methods can largely extend the calendar life of Si-LIBs and accelerate the application of these batteries for large-scale electrical vehicles and consumer electronics applications.

Silicon based Li ion batteries with extended calendar life

Where thousands of chemistry professionals meet to share ideas and advance scientific and technical knowledge. Spring 2023 abstracts, posters, and presentations will launch at the end of March.

ACS Spring 2023

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.