Embroidered Copper Microwire Current Collector for Improved Cycling Performance of Silicon Anodes in Lithium-Ion Batteries

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.

Fabrication of Si Nanoparticles@Conductive Carbon Framework@Polymer Composite as High‐Areal‐Capacity Anode of Lithium‐Ion Batteries

“…Interestingly, the cross‐linked framework structure of CNF framework exists among these cracks, which benefits to maintain the interparticle electrical contact and the structural integrity for electrode disks, as shown in Figure f. According to the previous reported work by Breitung et al ., the 3D Cu microwire network was used as current collector for Si‐based anodes instead of conventional Cu foil, which showed much enhanced capacity and reversibility due to the avoidance of the loss of electrical contact of active electrode regions and the higher degree of tolerance to cycling …”

Recent Advances in Silicon‐Based Electrodes: From Fundamental Research toward Practical Applications

“…Unfortunately, the high Li-ion accommodation of Si causes tremendous volume expansion, up to ≈300-400% when fully lithiated, creating several stability issues. [80,81] The continuous insertion and extraction of Li ions produce large mechanical stresses inside Si materials, leading to Si pulverization and electrode cracking (Figure 5a). Finally, dramatic morphologic variation from volume changes can cause severe electrode swelling, which results in delamination of the electrodes and current collectors, rapidly decreasing capacity.…”

Advanced 3D Current Collectors for Lithium‐Based Batteries

“…Besides the metal nanowire arrays that are assemblies of nanowires standing in parallel, metal nanowire papers with thicknesses of 10 µm to 1 mm and lateral size of centimeters consist of randomly stacked nanowires . The interconnected metal nanowires render the paper excellent electrical conductivity and a favorable mechanical strength .…”