Will supercapacitors replace lithium-ion batteries?

So far, the industry has unanimously agreed that lithium-ion batteries are still the main energy storage method for electric vehicles, but several companies have begun to consider using ultracapacitor products as a good supplement to lithium-ion batteries.

Neescap, a South Korean electronics company, announced on Tuesday that it would invest $9 million to expand the production capacity of its ultracapacitor products for transportation, power systems and consumer electronics. In the United States, there are three companies capable of designing and manufacturing materials and electrolytes required for ultracapacitor products: Graphene Energy, EnerG2 and Ioxus. Another company, EEStor, is backed by venture capital firm Kleiner Perkins Caufield & Byers and has signed an ultracapacitor supply agreement with electric car company Zenn.

Compared with traditional battery products, supercapacitors can store less electricity. Therefore, in plug-in electric vehicles at home, this capacitor cannot be used alone as a power supply device, but needs to be used in conjunction with a fuel cell. On the other hand, supercapacitors have the ability to quickly discharge the stored energy. In addition, the charging time of this capacitor is also very short, only a few seconds or minutes to complete the charging, and the performance will not be reduced after multiple charges.

Currently, this type of capacitor has been used in consumer electronics products such as digital cameras to provide energy for devices such as flashlights that require instantaneous large energy input. According to relevant experts, the main issue facing supercapacitors in the future is how to increase the working voltage of this capacitor so that it can work in a high-voltage environment.

According to engineers from Ioxus, supercapacitors are a good supplement to environmentally friendly energy sources, which can make power supply methods such as batteries, fuel cells, solar or wind power generation more perfect. At the same time, the materials used to make this capacitor are also quite environmentally friendly, and the price is also more acceptable.

Future development direction of supercapacitor technology:

Joel Schindall, a computer electronics engineer at the Massachusetts Institute of Technology, said that in the next few years, the energy storage capacity of supercapacitors will see a qualitative leap. The current supercapacitor products discharge 10 times faster than traditional batteries, while the energy storage capacity is only 5% of the latter under the same volume conditions.

He said: "Supercapacitors are very useful in some occasions where charging and discharging operations are frequently performed, such as in the regenerative braking system (the Coles system that the host of CCAV's five F1 programs keeps talking about). Of course, this product cannot currently replace batteries on a large scale."

Over the past five years, the research team led by Schindall has been studying how to replace the energy storage element in supercapacitors, porous activated carbon materials, with another type of energy storage element, carbon nanotube materials + conductive matrix. Earlier this year, they also established FastCap to commercialize the research results.

Schindall said that the energy storage capacity of supercapacitor products will eventually reach about 25% of that of batteries. The energy storage capacity of nanomaterials currently developed by MIT has reached twice the level of activated carbon materials. In the next few months, the research team led by him will also demonstrate a product with an energy storage capacity five times that of activated carbon.