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Hard carbons derived from glucose and glucosamine are synthesized via microwave-assisted hydrothermal carbonization (HTC) and subsequent pyrolysis treatment to be used as anode materials for lithium-ion batteries (LIBs). Related to the limited lithium ion intercalation to graphite (LiC 6 ) resulting relatively low theoretical capacity (372 mAh/g), silicon is considered as one of the most appealing anode materials for LIBs by exhibiting very high theoretical capacity (3578 mAh/g, based on Li 15 Si 4 ).However, silicon suffers from huge volume expansion during intercalation of lithium ions which causes rapid capacity fading. One of the most practical strategy to suppress this problem is to coat the silicon nanoparticles with carbonaceous materials. Herein, silicon is coated via microwave-assisted hydrothermal carbonization method in the presence of glucose or glucosamine which are then further pyrolyzed at 750 °C to obtain silicon-carbon composite anodes. Composite containing glucosamine (Si-GA-C-750) enables N-doped carbon evidenced by EDX and XPS analyses which contributes to obtain much enhanced electrochemical properties than that of glucose containing composite (Si-G-C-750).Additionally, higher Li + diffusion coefficient and smaller resistance values attest the advantageous nature of the N-doped anode material.

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Herein, the electrochemical performance of a new sodium‐based aqueous rechargeable battery is demonstrated consisting of Na0.44MnO2 as cathode and dissolved sodium polysulfide (i.e., Na2S5) as anolyte. Na0.44MnO2 synthesized through a solid‐state reaction method and dissolved Na2S5 anolyte are tested separately in a half‐cell configuration, both giving rise to stable cycling performances. As the anode side of the desired full‐cell configuration is at present dissolved in the electrolyte, the positive and negative electrodes need to be separated with an ion‐selective membrane that is permeable to sodium ions and impermeable to polysulfide species. Hence, Nafion is tested as a barrier to prevent the leakage of the dissolved polysulfides. After careful tuning of the osmotic pressure inside the Nafion membrane, leakage of the dissolved polysulfide from the anode to the cathode side is eliminated, resulting in a 0.8 V average voltage, low‐cost sodium‐ion aqueous cell.

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