Electrochemical capacitors, also called supercapacitors, store energy using either ion adsorption (electrochemical double layer capacitors) or fast surface redox reactions (pseudo-capacitors). They can complement or replace batteries in electrical energy storage and harvesting applications, when high power delivery or uptake is needed. A notable improvement in performance has been achieved through recent advances in understanding charge storage mechanisms and the development of advanced nanostructured materials. The discovery that ion desolvation occurs in pores smaller than the solvated ions has led to higher capacitance for electrochemical double layer capacitors using carbon electrodes with subnanometre pores, and opened the door to designing high-energy density devices using a variety of electrolytes. Combination of pseudo-capacitive nanomaterials, including oxides, nitrides and polymers, with the latest generation of nanostructured lithium electrodes has brought the energy density of electrochemical capacitors closer to that of batteries. The use of carbon nanotubes has further advanced micro-electrochemical capacitors, enabling flexible and adaptable devices to be made. Mathematical modelling and simulation will be the key to success in designing tomorrow's high-energy and high-power devices.

https://hal.archives-ouvertes.fr/hal-02417326/document

Materials for electrochemical capacitors

In this critical review, metal oxides-based materials for electrochemical supercapacitor (ES) electrodes are reviewed in detail together with a brief review of carbon materials and conducting polymers. Their advantages, disadvantages, and performance in ES electrodes are discussed through extensive analysis of the literature, and new trends in material development are also reviewed. Two important future research directions are indicated and summarized, based on results published in the literature: the development of composite and nanostructured ES materials to overcome the major challenge posed by the low energy density of ES (476 references).

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A review of electrode materials for electrochemical supercapacitors

Electrolytes and interphases in Li-ion batteries and beyond.

Lithium (Li) metal is an ideal anode material for rechargeable batteries due to its extremely high theoretical specific capacity (3860 mA h g−1), low density (0.59 g cm−3) and the lowest negative electrochemical potential (−3.040 V vs. the standard hydrogen electrode). Unfortunately, uncontrollable dendritic Li growth and limited Coulombic efficiency during Li deposition/stripping inherent in these batteries have prevented their practical applications over the past 40 years. With the emergence of post-Li-ion batteries, safe and efficient operation of Li metal anodes has become an enabling technology which may determine the fate of several promising candidates for the next generation energy storage systems, including rechargeable Li–air batteries, Li–S batteries, and Li metal batteries which utilize intercalation compounds as cathodes. In this paper, various factors that affect the morphology and Coulombic efficiency of Li metal anodes have been analyzed. Technologies utilized to characterize the morphology of Li deposition and the results obtained by modelling of Li dendrite growth have also been reviewed. Finally, recent development and urgent need in this field are discussed.

Lithium metal anodes for rechargeable batteries

Metal Oxides and Oxysalts as Anode Materials for Li Ion Batteries

This paper reports on the synthesis of Co3O4@graphene composites (CGC) and their applications as anode materials in lithium ion batteries (LIBs). Through a chemical deposition method, Co3O4 nanoparticles (NPs) with sizes in the range of 10−30 nm were homogeneously dispersed onto graphene sheets. Due to their high electrical conductivity, the graphene sheets in the CGC improved the electrical conductivity and the structure stability of CGC. CGC displayed a superior performance in LIBs with a large reversible capacity value of 941 mA hg−1 in the initial cycle with a large current density and an excellent cyclic performance of 740 mA hg−1 after 60 cycles, corresponding to 88.3% of the theoretical value of CGC, owing to the interactions between graphene sheets and Co3O4 NPs anchored on the graphene sheets. This synthesis approach may find its application in the design and synthesis of novel electrode materials used in LIBs.

Co3O4@graphene Composites as Anode Materials for High-Performance Lithium Ion Batteries

In this paper, a Fe3O4 nanocrystals@graphene composite (FGC) was synthesized via a chemical deposition method by using graphene oxide as a precursor. We also investigate the structures, physicochemical properties and applications of FGCs, involving superparamagnetic performance, and use as supercapacitors and lithium ion battery (LIBs). The results showed that the Fe3O4 NCs were formed and incorporated onto the surface of the graphene sheets. The composite material FGC with a micrometre scale structure possessed similar size as the graphene sheets and exhibited superparamagnetic behavior at room temperature. The supercapacitance values of the FGC composites were enlarged compared with those of the graphene sheets or Fe3O4 NCs, which is attributed to the interaction between the Fe3O4 NCs and the graphene sheets. Meanwhile, a superior rechargeable stability of FGCs used as an anode material in LIBs can be observed.

Superparamagnetic Fe3O4 nanocrystals@graphene composites for energy storage devices

http://www.timesnano.com/upfile/fck/20120709/20120709_143631_21363505.pdf

Manganese oxide/MWNTs composite electrodes for supercapacitors

The effect of gradient boracic polyanion-doping on structure, morphology, and cycling performance of Ni-rich LiNi 0.8 Co 0.15 Al 0.05 O 2 cathode material

https://www.rsc.org/suppdata/cc/c1/c1cc13462k/c1cc13462k.pdf

Meizhen Qu

Papers

Co3O4@graphene Composites as Anode Materials for High-Performance Lithium Ion Batteries

Superparamagnetic Fe3O4 nanocrystals@graphene composites for energy storage devices

Manganese oxide/MWNTs composite electrodes for supercapacitors

The effect of gradient boracic polyanion-doping on structure, morphology, and cycling performance of Ni-rich LiNi 0.8 Co 0.15 Al 0.05 O 2 cathode material

Enhanced anode performances of the Fe3O4–Carbon–rGO three dimensional composite in lithium ion batteries