Uniform Nano-Sn/C Composite Anodes for Lithium Ion Batteries

Abstract

Nano-Sn/C composites are ideal anode materials for high energy and power density Li-ion batteries. However, because of the low melting point of Sn and the tendency of grain growth, especially during high temperature carbonization, it has been a significant challenge to create well-dispersed ultrasmall Sn nanoparticles within a carbon matrix. In this paper, we demonstrate an aerosol spray pyrolysis technique, as a facile and scalable method, to synthesize a nano-Sn/C composite with uniformly dispersed 10 nm nano-Sn within a spherical carbon matrix. The discharge capacity of nano-Sn/C composite sphere anodes maintains the initial capacity of 710 mAh/g after 130 cycles at 0.25 C. The nano-Sn/C composite sphere anodes can provide ~600 mAh/g even at a high rate of 20 C. To the best of our knowledge, such high rate performance for Sn anodes has not been reported previously. The exceptional performance of the nano-Sn/C composite is attributed to the unique nano-Sn/C structure: (1) carbon matrix offers mechanical support to accommodate the stress associated with the large volume change of nano-Sn, thus alleviating pulverization; (2) the carbon matrix prevents Sn nanoparticle agglomeration upon prolonged cycling; and (3) carbon network provides continuous path for Li ions and electrons inside the nano-Sn/C composite spheres.

Metallic Sn‐Based Anode Materials: Application in High‐Performance Lithium‐Ion and Sodium‐Ion Batteries

“…People have varied the carbon precursors to produce the carbon matrix, including micromolecular organics,22, 26, 49, 50, 52, 56 polymer,6, 53, 57, 58, 59 saccharides,48, 51, 60, 61, 62 resins,55, 63, 64 graphene,65, 66, 67 etc. Derrien et al49 reported a synthesis of nano‐Sn (with a small amount of SnO 2 ) embedded in a carbon matrix.…”

“…Benefiting from the small‐size effect, the volume expansion and particle aggregation of active materials are relieved 58, 130…”

“…A series of 0D Sn/C composites have been successfully prepared by this method 56, 58, 133. As shown in Figure 12 a,b, nano‐Sn homogeneously embedded in carbon nanosphere composites were synthesized using aerosol spray pyrolysis method 50.…”

Surfactant-assisted synthesis of Sn nanoparticles via solution plasma technique

“…This leads to pulverization of the tin anode and loss of electric contact to current collector, resulting in poor cycling performance 4,5 . Consequently, several strategies, including the formation of tin-based alloy 6,7 , reducing the particle size to nanoscale, and dispersion of nano-Sn in conductive carbon matrix to form tin/carbon composite [8][9][10][11][12][13][14][15][16][17][18] , have been proposed to mitigate this volume change issue.…”

Failure Prediction of High-Capacity Electrode Materials in Lithium-Ion Batteries

“…8,9 Other electrode materials such as Ge and Sn also have considerable theoretical specific capacities (1623 mA h g −1 for Li 22 Ge 5 and 700 mA h g −1 for Li 22 Sn 5 ). 4,7,10 However, the large number of Li-ions inserting into high-capacity electrode materials may result in a huge volume change (400% for full lithiation of Si), 6 and a series of shortcomings: fracture or pulverization of active materials, breakage of a conduction path for electrons and lose of electrical contact, and destruction of solid electrolyte interphase formed by the reaction between active materials and electrolyte. They can rapidly fade electrochemical properties of active materials and result persistent decrease of their long-term coulombic efficiency.…”