Supercapacitors: Fast Charge and Discharge?

Rich results on Google's SERP when searching for "supercapacitors fast charge"

Supercapacitors differ from batteries mainly due to their fast charge and discharge. We, at ZTT Supercapacitor, often receive requests regarding supercapacitors from various areas and countries. However, it seems there is some misunderstanding between supercapacitors and lithium batteries.

2.7V100F ZTT Supercapacitor

What is a Supercapacitor?

Supercapacitors are also sometimes known as supercaps, ultracapacitors, or electric double-layer capacitors. In short, they have higher capacitance and lower voltage limits than other types of capacitors. While functionally, they lie somewhere in between electrolytic capacitors and rechargeable batteries.

(Cutaway diagram of the supercapacitor)

In terms of power storage, there is some common confusion. First of all, we can simply talk about fast charging and discharging.

Fast Charge and Discharge

The charge time of a supercapacitor is 1–10 seconds. The initial charge can be made very fast, and the topping charge will take extra time. 

Here, we list some comparison items among Lead-acid batteries, Supercapacitors, and Lithium-ion batteries.

ItemsLead-acid BatterySupercapacitorLithium-ion Battery
VolumeModerate size
(compared with the other two)
LargestSmaller than lead-acid batteries and supercapacitors
 (under the same storage capacity)
HeavyModerate, about half of the lead-acid batteryLighter than supercapacitors
Charging MethodThe whole group is charged in seriesThe whole group is charged in seriesThe whole group is charged in series
Nominal Voltage of Cell<2V2.7~3.0V3.6V
TemperatureWorking temperature range from -25°C to +45°C (optimal at 25°C)Working temperature ranges from -40℃ to +70℃Working temperature range from -20℃ to +60℃ Built-in heater
Charge and Discharge TimeCycle full charge for 10 hoursCan be fully charged in tens of secondsCycle full charge for 1-6 hours
Power DensityLow, 20-200W/kgHigher, 1000-20000W/kgHigh, 320W/kg
Energy DensityHigh, about 35Wh/kgAbout 1/10 of the battery, 3-15Wh/kgHigh, about 4-5 times that of the battery, 190Wh/kg
Cycle Life1.5 years
(high-rate charge and discharge or over-discharge points have a greater impact on life)
8-10 years3-5 years
Charge RetentionLow self-dischargeLarge leakage currentLow self-discharge
MaintenanceThe battery is sealed and maintenance-free and can be replaced when it expiresCompletely maintenance-freeMaintenance-free


The main difference is a supercapacitor’s ability to store energy doesn’t come from chemical reactions. But rather from the way that its physical design allows it to hold negative and positive charges apart. This makes supercapacitors very fast at charging and discharging, much faster than batteries.

> Feel free also to contact us for more information:

> Keep yourself up-to-date on Supercapacitors News, Trends, Applications, and more with our LinkedIn Page.

> For more information about our Supercapacitors, also visit our product page.

Lastest news

July 5, 2023
[Updates on ZTT BESS Deployments] BESS can play a wide variety of roles. In the case of grid-scale systems, today typically provide grid balancing services to grid operators, balance peaks and troughs in energy prices by trading in the electricity market, and provide capacity under agreements as with other renewables like solar and wind. What...
June 26, 2023
As we mentioned before, Battery Energy Storage System (BESS) can help balance the supply and demand of power generation, distribution, and consumption. Then, how can energy storage help “reduce peaks” as summer comes and the temperature rises? Overview Energy storage can help “reduce peaks” during times of high temperatures by storing excess energy generated during...
June 20, 2023
Thank you for visiting ZTT New Energy at EES Europe 2023! We actively participated in the EES Europe 2023, which is part of the Smarter E Europe held in Germany from 14-16 June. The event offered an excellent opportunity for us to increase our visibility and build brand awareness. Visitors were impressed by ZTT New...
June 14, 2023
Battery energy storage systems (BESS) provide a steady supply of low-cost electricity, reducing our collective dependence on fossil fuels and cutting carbon emissions for a cleaner environment. That’s why BESS containers are increasingly for storing renewable energy generated from wind and solar power. However, managing the heat generated by the batteries during the charging and...
June 6, 2023
[Supercapacitors for energy savings] At present, China’s petroleum and chemical industry is at a historic crossroads of industrial transformation. While green, low-carbon, high-quality development is a major international and domestic trend. Which is rapidly contributing to the increasing demand for renewable energy technologies in the oilfield. Then, what ZTT Supercapacitor can do to optimize the...
May 31, 2023
[ZTT BESS Mongolia] On Tuesday, May 30ᵗʰ, 2023, ZTT New Energy successfully delivered its BESS containers to Mongolia’s first Utility-scale energy storage project. Project Background As predicted before, on successful completion, the project will supply 58.5 gigawatt-hours of clean peaking power annually. And support the integration of an additional 859 gigawatt-hours of renewable electricity into...