Compositionally-graded silicon–copper helical arrays as anodes for lithium-ion batteries

Designing self-standing silicon-copper composite helices as anodes for lithium ion batteries

“…In all samples, the diameters of helices are around 100e250 nm, which is less than the critical diameter for Si nanocolumns (300 nm) to deliver maximum resistance against the stress formed during cycling [44]. Pure Si helix with similar process parameters have been produced in our previous study [45]. Even though the diameter of the helix was less than~300 nm, the helix morphology in the Si film had shown irregularities along the thickness compared to that of the SiCu composite.…”

“…Fig. 5aec shows that all SiCu anodes operate for 100 cycles with success, while the bulk Si anode or thicker Si film do not [45]. The reason for this success is the synergy between the morphology and the structure of the films prepared by IA-GLAD.…”

Improving the Performance of Micro‐Silicon Anodes in Lithium‐Ion Batteries with a Functional Carbon Nanotube Interlayer

“…Silicon anode is particularly strong candidate for future development because of high theoretical capacity up to ∼3600 mAh g −1 , low discharge capacity about 0.5 V, abundant resource and mature fabrication techniques ,. However, unfortunately, silicon anode still exhibits quite unstable during long cycling, particularly for the commercial silicon material with irregular morphology and large particle size (larger than hundreds nanometers) . On one hand, silicon anode undergoes a big strain and a large volume expansion about 400 % upon full lithium insertion process,, leading to pulverization and aggregation of the silicon and loss of electrical contact with the current collector, which would induce large irreversible capacity losses during cycling.…”

“…[1,2] However, unfortunately, silicon anode still exhibits quite unstable during long cycling, particularly for the commercial silicon material with irregular morphology and large particle size (larger than hundreds nanometers). [3][4][5][6] On one hand, silicon anode undergoes a big strain and a large volume expansion about 400 % upon full lithium insertion process, [7,8] leading to pulverization and aggregation of the silicon and loss of electrical contact with the current collector, which would induce large irreversible capacity losses during cycling. Some of the silicon anode even fall below 50 % of their initial capacities after less than twenty cycles.…”

Copper-Based Nanomaterials for High-Performance Lithium-Ion Batteries

“…Restrictions in silicon based anodes have been the subject of many researches for years. [159] As an innovative approach, Polat et al have adopted ion assisted deposition technique to produce a unique helical shaped gradient film in which the Cu/Si atomic ratio decreases from the bottom to the top of the coating. This unique film (high surface area) has more spaces to create promoting mechanical integrity and reaction between active materials (silicon) with lithium ions.…”