Among the key components in batteries, binders play a vital role by interconnecting active materials and conductive additives and facilitating the coating of electrode materials on the desired substrates thus...

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Mn 3 O 4 nano-octahedrons embedded in N-doped graphene oxide (MNGO) nanosheets were synthesized using a simple, energy-efficient, and rapid microwave-digested hydrothermal route in a single step. The structural and morphological aspects of synthesized materials were evaluated by XRD, IR, Raman, FE-SEM, and HR-TEM techniques. Then, the composite MNGO was tested for its Li-ion storage properties and compared with reduced graphene oxide (rGO) and Mn 3 O 4 materials. The MNGO composite exhibited superior reversible specific capacity, excellent cyclic stability, and outstanding structural integrity throughout the electrochemical studies. The MNGO composite showed a reversible capacity of 898 mA h g −1 after 100 cycles at 100 mA g −1 and Coulombic efficiency of 97.8%. Even at a higher current density of 500 mA g −1 , it exhibits a higher specific capacity of 532 mA h g −1 (~1.5 times higher than commercial graphite anode). These results demonstrate that Mn 3 O 4 nano-octahedrons embedded on N-doped GO are a highly durable and potent anode material for LIBs. Supplementary Information The online version contains supplementary material available at 10.1007/s11581-023-05035-6.

Inorganic aqueous binders (IAB) are an emerging class of aqueous binders. They offer exceptional physicochemical properties like intrinsic ionic conductivity, high thermal stability (>1000°C), and environmental benignity making them attractive. In a previous study, we found that graphite anode shows improved electrochemical performance with these binders as compared to conventional PVDF binder for lithium-ion batteries (LIB). However, the cyclic performance of graphite-IAB at a higher rate (e.g., 1C) showed a declining trend. We attributed it to the poor binding strength between graphite and IAB due to insufficient functional groups in graphite. Therefore in this report, SiOx-based surface coatings of graphite are employed to improve its rate capability with silicate-based IAB by providing functional silicon oxide polymorphs on the coated graphite as an intermediate layer. The nature and structural arrangement of these coatings are investigated by tip-enhanced Raman spectroscopy (TERS), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM). Optimized SiOx-coated graphite (GS) with sodium metasilicate binder leads to excellent cyclic stability with a capacity retention of >90% at 20C for more than 4000 cycles. A high specific capacity of >315 mAhg-1 at 2C, stable for over 1000 cycles, is achieved for GS with IAB. The improved performance of the coated graphite is attributed to ameliorated binding with IAB as well as stable solid electrolyte interphase. We propose inorganic aqueous binders in combination with SiOx-coated graphite as an approach to realize a stable anode for LIB.