Dealloying Synthesis of Silicon Nanotubes for High‐Performance Lithium Ion Batteries

Abstract

Practical applications of silicon-based anodes in lithium ion batteries have attracted unprecedented attentions due to the merits of extraordinary energy density, high safety and low cost. Nevertheless, the inevitable huge volume change upon lithiation and delithiation brings about silicon electrode integrity damage and fast capacity fading, hampering the large-scale application. Herein, a novel one-dimensional tubular siliconnitrogen doped carbon composite (Si@NC) with a core-shell structure has been fabricated using silicon magnesium alloy and polydopamine as a template and precursor. The asobtained composite exhibits remarkable specific capacity and ultrafast redox kinetics, an outstanding cycling stability with fine capacity of 583.6 mAh g À 1 at 0.5 A g À 1 over 200 cycles is delivered. Moreover, a full cell matched with LiFePO 4 cathode has demonstrated a reversible capacity of 148.8 mAh g À 1 with high Coulombic efficiency as well as an excellent energy density of 396 Wh kg À 1 . The nanotube structure engineering and silicon confined in nitrogen doped carbon effectively alleviate the volume expansion and endow the composite with superior stability. The robust strategy developed here gives a new insight into designing silicon anodes for enhanced lithium storage properties.

Innovative Solutions for High-Performance Silicon Anodes in Lithium-Ion Batteries: Overcoming Challenges and Real-World Applications

“…These nanowires exhibited commendable CE of 73% and improved cycle life, attributed to their well-structured nature accommodating substantial volume changes. Zhao et al [ 97 ] introduced a novel 1D tubular silicon-nitrogen-doped carbon composite (Si@NC) with a core–shell structure, utilizing silicon magnesium alloy and polydopamine as a template and precursor (Fig. 8 a).…”

Silicon Solid State Battery: The Solid‐State Compatibility, Particle Size, and Carbon Compositing for High Energy Density

“…[104,105] Material designing, [106] surface coating, [107,108] and composite (with conductive [109] or inactive [110] medium) are promising approaches toward extended cycle life superior performance. Theoretically, reducing bulk Si to the nanoscale (Si nanowires, [111] nanotubes, [112] nanospheres, [113] hollow nanospheres, [114] and nanosheets) [115] helps less cracking and its side effects. In contrast, there are main problems when it comes to realistic tests.…”

Ongoing advancement in examining si-based anode materials for lithium ion batteries

“…Silicon is a great competitor for a new generation of negative electrode materials. With its great theoretical capacity (~4200 Ah/g), low lithium ion insertion potential (~0.3 V vs. Li/Li+), and abundant reserves in the world, silicon is a highly desirable material for energy storage technology [3]. However, amidst the process of inserting and extracting lithium ions in LiBs, the significant expansion in volume during the addition and extraction of Li+ causes the active material to pulverize and fracture, resulting in a slew of issues, including inadequate cycling performance of the electrode, rapid decay in capacity, and potential failure of the electrode.…”

“…Silicon/Carbon composite materials can be enhanced not only by simple mixing or carbonization to improve Si anode performance but also by utilizing a more sophisticated core-shell structure. The complete shell provided by this structure functions as an effective buffer against silicon's serious volume expansion, ultimately guaranteeing the Si electrode's integrity [3]. Moreover, this structure serves to prevent Si from contacting the electrolyte constantly, resulting in enhanced stability of the SEI film and a reduction in side reactions stemming from interactions between Si and the electrolyte.…”