Nanostructured Ni3.5Sn4 intermetallic compound: An efficient buffering material for Si-containing composite anodes in lithium ion batteries

Intermetallic Ni3Sn4-based graphene@carbon hybrid composites for lithium-ion batteries

“…The carbon layer on the surface of the anode electrodes causes the surface of the Ni 3 Sn 4 intermetallic compounds to reduce the SEI layer formed after the reaction with the electrolyte. Graphene reinforcement is also provided a mechanically stable matrices for Ni 3 Sn 4 active materials, which annihilates problems associated with the stresses resulting from large volumetric variations that occurs because of the continuous electrochemical cycles and enhances the structural integrity of the Ni 3 Sn 4 electrode …”

“…Improved electrode performance of the yolk‐shell Ni 3 Sn 4 /graphene nanocomposite electrodes was due to its novel architecture, the synergistic effects of yolk‐shell and graphene on the electrochemical performance, the suppression of side reactions between the nanocomposite and the electrolyte and an optimization of the solid electrolyte interface film. It should also be noted that the nanograin size of Ni 3 Sn 4 in the hybrid composite structure are most likely enhanced the electrochemical properties by shortening the conduction paths for electrons and Li‐ions . Notable electrochemical performance increment with yolk‐shell freestanding Ni 3 Sn 4 could be attributed to the encapsulation of Ni 3 Sn 4 particles into a carbon shell.…”

“…Calculations of gravimetric and volumetric energy densities of the half cells are performed according to a previous study performed by Lu et al 21 Graphene reinforcement is also provided a mechanically stable matrices for Ni 3 Sn 4 active materials, which annihilates problems associated with the stresses resulting from large volumetric variations that occurs because of the continuous electrochemical cycles and enhances the structural integrity of the Ni 3 Sn 4 electrode. [22][23][24][25] The discharge capacity of Ni 3 Sn 4 , yolk-shell Ni 3 Sn 4 , and yolk-shell Ni 3 Sn 4 /graphene nanocomposites vs cyclic capacity curves are also presented in Figure 8. The initial specific capacities of Ni 3 Sn 4 , yolk-shell Ni 3 Sn 4 , and yolkshell Ni 3 Sn 4 /graphene nanocomposites are obtained as 712, 714, and 716 mAh g −1 , respectively.…”

“…It should also be noted that the nanograin size of Ni 3 Sn 4 in the hybrid composite structure are most likely enhanced the electrochemical properties by shortening the conduction paths for electrons and Li-ions. [22][23][24][25][26] Notable electrochemical performance increment with yolk-shell freestanding Ni 3 Sn 4 could be attributed to the encapsulation of Ni 3 Sn 4 particles into a carbon shell. The enhancement in the structural stability after 250 cycles could also be attributed to the buffering effects of both graphene and carbon shell.…”

Electrochemical performance of Si/CeO2/Polyaniline composites as anode materials for lithium ion batteries

“…But its application is seriously restricted due to relatively undesirable conductivity and poor cycling stability which is attributed to significant volume change during lithiation and delithiation processes. To overcome the problems, many researchers adopt lots of methods such as Si-C[2-12], Si-metal [13][14][15][16][17][18][19][20] and Si with special structure (core-shell [21][22][23], porous [24,25], nanotube [26], nanowire [27], film [28]). In Si-C and Si-metal composites above-mentioned, the C and metal can enhance the conductivity and buffer the mechanical stress caused by volume change of Si as a matrix; and the special structure also provide enough space to accommodate the expansion of Si.…”