In this piece, IDTechEx Technology Analyst Daniel Parr explains why carbon-based materials for electrodes have dominated in the supercapacitors market for electric double-layer supercapacitors (EDLCs) and why IDTechEx expects this will continue to be the case in the coming decade.
The performance of supercapacitors is dominated by design and materials choice. A supercapacitor is generally formed of two electrodes, two current collectors, an electrolyte, a separator, and binders/additives, and in each of these components, materials innovations can lead to significant improvements in power density, energy density and cycle life. Carbon-based materials for electrodes have dominated in the supercapacitors market for electric double-layer supercapacitors (EDLCs), due to low cost, cycling durability and conductivity, and IDTechEx expects this will continue to be the case in the coming decade. To find out why in detail, see the related report: “Supercapacitors 2026-2036: Technologies, Applications and Forecasts”.
There are a number of options for electrode material for supercapacitor developers, including carbon-based materials, transition metal oxides, conducting polymers, composite materials and other advanced alternative materials. The first three of these are established commercially, offering differing advantages and disadvantages between them, while composite materials describe a composition of two or more electrode materials, aiming to gain the benefits of all but at higher cost, and advanced alternative materials include less technologically mature materials such as perovskites and metal organic frameworks.
Currently, carbon-based materials offer the most competitive performance of all, including the highest electrical conductivity, cyclic stability, cost, power density and energy density, though with slightly more complicated fabrication methods required (i.e. higher CapEx). While conducting polymers offer slightly easier fabrication, lower energy density and lower power density make them non-viable in many cases, while transition metal oxides remain too expensive to see commercial use. Carbon-based materials will continue to dominate for the foreseeable future.
Carbon-based material differentiation
Carbon-based materials describes an array of carbon structures, from nanotubes to graphene and activated carbon. All of them are designed carefully in order to improve their specific area, which in turn increases capacitance (as more charges can be stored in the same space). These materials are distinguished by their ease of manufacture, capacitance and power density. Generally, smaller pores in the lattice structure of the material lead to improvements in specific energy and capacitance due to more charges being stored in the same area, but reductions in specific power due to higher equivalent specific resistance (ESR). Due to this relationship, a tuneable pore size is highly valued, as this allows supercapacitors that can be targeted towards either higher power density or higher energy density, depending on application.
There is significant room for innovation in development of carbon-based materials, as these materials are highly tuneable based on different activations, lattice designs and seeding processes. Examples of carbon-based electrode material developments are included below:
Nippon Chemi-Con
Nippon Chemi-Con, a developer of aluminium electrolytic capacitors, uses activated carbon powder for its electrodes, which is pasted onto aluminium foil current collectors, enabling high capacitance and low resistance.
Skeleton Technologies
Skeleton Technologies, formerly Black Magic GmbH, has developed a novel material for its supercapacitor electrodes, named Curved Graphene. This material is described as having the same hexagonal structure as graphene but rather than being planar, the structure is ‘crumpled’ into a 3D ball-like form, which massively increases the effective surface area of the material. This material has a tuneable pore size with much higher micropore ratio compared to activated carbon (0.95 vs 0.5-0.6). The company aim to scale manufacturing of this material in 2025/2026.
Musashi Energy Solutions
Musashi Energy Solutions is a developer of hybrid supercapacitors, offering both capacitive and faradaic charge storage. For its products, the company uses activated carbon for the cathode and li-doped activated carbon for the anode, which enables both capacitive charge storage and li-ion redox reactions.
SECH SA
SECH SA, a subsidiary of Sieyuan Electric Co. Ltd, has developed supercapacitors using activated carbon electrodes with the aim to achieve a highly tuneable pore size. This allows for optimization of charge storage depending on the electrolytic material used and the application (i.e. high power density or high capacitance can be favoured). The company focused on providing custom solutions to specific applications, rather than offering primarily standardized products.
The array of materials for supercapacitors is broad across many components and material categories, however carbon-based materials will continue to be a core part of supercapacitor designs over the coming decade, due to lower costs and higher performance.
Of the different carbon-based materials, activated carbon and 3D graphene materials are especially promising, however due to the differentiation of materials through pore size, conductivity, cost and capacitance, no one material is expected to become the dominant choice for supercapacitor electrodes. To find out more about materials for other components in supercapacitors, see the recent report by IDTechEx: “Supercapacitors 2026-2036: Technologies, Applications and Forecasts”.
