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Abstract There are ongoing efforts to improve the energy density of current day Li‐ion batteries by using alloy‐based anodes such as Si, Sn, or SnO 2 in place of graphite. Here we report template‐assisted synthesis of Sn@C microspheres and SnO 2 @C microbowls prepared by phloroglucinol (P) − formaldehyde (F) gel method. The structural and morphological characterizations are carried out using XRD, FESEM, and HR‐TEM. The electrochemical performance of SnO 2 @C as anode for Li‐ion battery is investigated through cyclic voltammetry (CV) and galvanostatic charge‐discharge cycling. At 1C rate, SnO 2 @C delivers a discharge capacity of 651 mA h g −1 over 150 cycles. Even at 5C rate, a reversible capacity of 494 mA h g −1 is observed with 72% of capacity retention over 200 cycles. Electrochemical impedance measurements also infer faster Li‐ion transport kinetics in the electrode material. The postmortem FESEM images on electrochemically cycled material show that porous hollow structure is retained even after prolonged cycling. For comparison, the Li storage property of Sn@C microspheres (MS) tested as anode for Li‐ion battery applications. This Sn@C composite delivered an excellent cycling capacity of 636 mA h g −1 at 1C rate over 400 cycles. When cycled at higher rate 5C, Sn@C composite exhibits high reversible capacity of 257 mA h g −1 with 68% of capacity retention over 250 cycles. These results highlight that combination of hollow architecture and porous carbon matrix of Sn@C and SnO 2 @C electrode provides better mechanical support to alleviate volume expansion issue of Sn electrode.
Gurunathan et al. (Thu,) studied this question.