Supercapacitors with batteries or fuel cells: result happiness
Jun 11, 2015 Dr Peter Harrop
IDTechEx interviews in Japan have established that supercapacitors across lithium-ion batteries in cars can increase range by 10% by permitting deep discharge, provided suitable batteries are used that can tolerate such a regime. Supercapacitors across batteries also extend life, permit a smaller battery of simpler, lower-cost construction to be used, not possessing high power density. They enable power surges when required as with a full bus starting on a hill or a designer car accelerating exceptionally rapidly. In the other direction they permit ABB TOSA buses to charge with hundreds of kilowatts in seconds at bus stops.
Across fuel cells these supercapacitor benefits apply but also a reduction of power electronics components is enabled. Supercapacitors across both batteries and fuel cells are a marriage made in heaven. Indeed, supercapacitors are being made into car bodywork experimentally so they take no space at all and add negligible weight.
So much for electric vehicles, but what about the chronic problem of wearable electronics and mobile phones failing in hours as more and more gas guzzling features are added such as NFC and larger displays? A thin sheet of supercapacitor wrapped around the battery in your cell phone could squeeze out enough extra energy to enable you to use your phone for a lot longer than usual. That is the latest marvel from startup the Paper Battery Company in the USA, which has been working on the technology for the past six years and has just started to get its thin, conformal supercapacitors into the hands of phone and device makers for testing.
Dave Rich, head of new technologies and applications at Paper Battery Company, uses a metaphor of an exercise machine to explain how it works. Biking or running at a moderate pace for a long time is a good fit for a battery, but when you hit the peaks and valleys on the exercise program, the supercapacitor kicks in but it cannot store enough energy to do everything.
Paper Battery Company's supercapacitor sheets use commercially available materials, so low cost is an objective. The company has innovated around the manufacturing, notably printing with its own custom ink. The processing of the materials and the packaging and architecture of the device are unique, giving one of the thinnest supercapacitors. It is 0.4 mm across and as wide as four sheets of paper stacked together.
Some researchers in labs are working on similar types of ultra lightweight supercapacitors. Scientists at Nanyang Technological University in Singapore, Tsinghua University in China and Case Western Reserve University in the U.S. recently demonstrated a fiber-like supercapacitor that could one day be woven into clothing. This is also a focus of the seven nation European Powerweave project which even plans an overlayer of photovoltaics on such fiber. Your shirt recharges your phone?
Paper Battery Company recently closed on a modest $3 million Series A round. Investors Caerus Ventures, Tylt Lab and longtime materials and energy investor Tom Baruch (the founder of CMEA Capital) participated in the deal. The company has raised $5 million to date, but it plans to raise more in another round. Battery companies typically need at least ten times that to get going and there is far more competition in batteries with bankruptcies every year. However, the bottom line is that we need both - batteries and supercapacitors, sometimes alone and sometimes together.
Top image: ABB