Abstract
Si holds great promise as an alloying anode material for Li-ion batteries with improved energy density because of its high theoretical specific capacity and favorable operation voltage range. However, the large volume expansion of Si during electrochemical reaction with Li and the associated adverse effects strongly limit its prospect for application. Here, we report on the use of three-dimensional instead of flat current collectors for high-capacity Si anodes in an attempt to mitigate the loss of electrical contact of active electrode regions as a result of structural disintegration with cycling. The current collectors were produced by technical embroidery and consist of interconnected Cu wires of diameter <150 µm. In comparison to Si/Li cells using a conventional Cu foil current collector, the embroidered microwire network-based cells show much enhanced capacity and reversibility due to a higher degree of tolerance to cycling.
Highlights
To a number of undesired side reactions such as increased electrolyte decomposition[21,22,23,24]
Small-size particles are often used in an attempt to somewhat counteract these adverse effects and to achieve fast kinetics or, in other words, short solid-state diffusion lengths for efficient charge transfer[18,25,26]
The current collectors were embroidered on polyester (PES) fabric using 80 μm-diameter Cu wire as front yarn
Summary
To a number of undesired side reactions such as increased electrolyte decomposition[21,22,23,24]. Small-size particles are often used in an attempt to somewhat counteract these adverse effects and to achieve fast kinetics or, in other words, short solid-state diffusion lengths for efficient charge transfer[18,25,26]. The reasons are that nanoscale Si, when in amorphous form, is known to be able to withstand stress-induced cracking to a higher degree than microcrystalline material and that pure Si is an insulator[27,28,29]. The loss of electrical contact of active electrode regions as a result of crack formation and delamination from the current collector with cycling remains one of the major challenges of Si anodes
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
