In 2010, there were no Chinese manufacturers in the top 10 supercapacitor manufacturers – but in 2020, 40% of them are Chinese.

This is one of the findings in the IDTechEx Research report, “Supercapacitor Markets, Technology Roadmap, Opportunities 2021-2041”.

The rise of Chinese companies has been achieved by world-class R&D, being in one of the largest markets globally, strong investment and government support including protective trading.

However, according to the report, China is not leading in capacitor-supercapacitor hybrids where the US saw a $7-million follow-on order recently.

Raghu Das, CEO of IDTechEx, comments: “Supercapacitor manufacturers used to be divided into those making small ones for electronics and those that also made similar flat or cylindrical formats for electrical engineering such as the archetypal 2.7V 3000F cylinder.

“No longer. A considerable market for even large supercapacitors is rapidly emerging.

“The first big success with large ones is boxed car stop-starters at around 20Wh, with over five million sold. The number of auto makers going for that fit-and-forget, grab more electricity, waste less electricity proposition still increases.

“The natural extension of this logic is the newly committed adoption of larger supercapacitors for peak-shaving and acceleration boosting at 30-100Wh across the batteries in mild hybrid cars then full hybrid then totally replacing the lithium-ion battery if pure electric cars have not destroyed the hybrid car business by then.”

The new large versions appear in trains at 1kWh, while 1MWh appears as hospital and data centre uninterruptable power supplies that double for peak shaving.

This is a long way from small supercapacitors usually made to standards, easy to make and mostly commoditised at prices of 1 cent/F or less.

IDTechEx counts 89% of supercapacitor manufacturers making them, although Panasonic recently exited this market. Of these manufacturers, 37% are in China because it exports them strongly. However, the country’s share of the supercapacitor value demand is only 27% because of low pricing and lateness into car stop-start.

An exception to the commoditisation trend is small supercapacitors in the form of battery-supercapacitor hybrids working at 150C, capacitor-supercapacitor hybrids beating tantalum electrolytics on ripple and one-fifth to one-tenth of the size and weight, and odd formats such as those for watch or smart card usage. Those working at 85C, -40C and 3V as single cells are less common and in demand.

Battery-supercapacitor hybrids (BSH) are almost always lithium-ion capacitors. They offer higher energy density often with effectively infinite cycle life and better charge retention than pure supercapacitors. Their energy density several times that of pure EDLC supercapacitors.

IDTechEx research shows that 24% of supercapacitor manufacturers now have a BSH range and, of those, 32% are made in China where they are most successful commercially. China leads the world here, partly because they have so many large BSHs.

Several companies declare their supercapacitors to be “graphene” as a badge of honour. It can mean non-flammable, relatively non-toxic, no use of the volatile, toxic carcinogen acetonitrile, valuably improved series resistance, better voltage and energy density in a pure EDLC – all good things justifying higher price.

Das adds: “IDTechEx measures that 8,75% of supercapacitor manufacturers now offer graphene versions, up from zero ten years ago. With 43% of the manufacturers using graphene in China, they are ahead in numbers – though certainly not in graphene supercapacitor research, much of which is aimed at the massive emerging market for replacing lithium-ion and lead-acid batteries with highest energy density of 100Wh/kg or more.

“In research, this is usually achieved by boosted pseudocapacitance though some perfect the technology of the newly commercial 100 Wh/kg lithium-ion supercapacitors. Thirty-three percent of supercapacitor material research graphene-centric followed by carbon nanotubes then metal organic frameworks.”

Large supercapacitors are more difficult to make, more profitable and represent the majority of the addressable market 2021-2041. Unlike small ones, they typically come with integral power electronics for optimal safe operation, microprocessors for intelligent response, often cooling systems.

Although 47,5% of supercapacitor manufacturers now claiming to make them, many of those are barely in the business, their web entries being more of a wish list that reality. Thirty-four percent of these are in China which is not dominant in the market although it is coming up.

This is assisted by the fact that a disproportionate amount of the demand for large supercapacitors is in China, with the government requesting that all parts of trains and buses be made in China.

On the other hand, China is badly behind in researching supercapacitor bodywork, smart skin and other radical advances scoped in the IDTechEx Research report, “Supercapacitor Materials and Formats 2020-2040”.

Das predicts: “Acquisitions and mergers will continue. One billion dollar supercapacitor businesses may be created by 2045. If the addressable markets we have analysed are strongly penetrated, then it will be much earlier. Given past disappointments, our upside forecast currently stands at $7-billion in 2041”.