Advantages and disadvantages of electric double layer capacitors

Electric double layer capacitors, also known as super capacitors, are a new type of energy storage device, an electrochemical capacitor with high energy density, which is thousands of times higher than ordinary electrolytic capacitors. Electric double layer capacitors have the characteristics of short charging time, long service life, good temperature characteristics, energy saving and environmental protection.

Advantages:

1. Long service life, has been degraded hundreds of thousands of charging cycles. Because the large number of charging and discharging cycles of capacitors (compared to the 200 to 1000 cycles of most commercially available rechargeable batteries, millions of times or more) will last the entire life cycle of most equipment, which makes the equipment environmentally friendly . Rechargeable batteries usually wear out for several years, and their highly active chemical electrolytes pose potential disposal and safety risks. Only charge at an ideal speed under favorable conditions, and optimize battery life with as little as possible for certain chemicals. The electric double-layer capacitor is combined with the battery for charging adjustment, storing energy from other sources to achieve the purpose of load balancing, and then using a rechargeable battery, any excess energy can provide help at an appropriate time.

2. Low cost per cycle.

3. Good reversibility.

4. Simple charging method. Insufficient charging test is necessary, so there is no danger of overcharging.

5. The charge and discharge rate is very high.

6. Improve safety, non-corrosive electrolyte, low toxic substances.

Disadvantages:

1. Very low internal resistance-allows extremely fast discharge. A short circuit is more dangerous than any other capacitor or electrochemical battery.

2. Has the highest dielectric absorption among all types of capacitors.

3. High self-discharge rate-much higher than electrochemical batteries.

4. Low maximum voltage is required in series to obtain higher voltage, and voltage balance may be required.

5. Compared with electrochemical batteries, the voltage of electric double layer capacitors (including other types of capacitors) will drop significantly with the release of energy. Its charging and discharging require complex electronic control and switching equipment, which will cause energy loss.

Electric double layer capacitors are widely used. Used as a power balance power supply for lifting devices, it can provide super-high current power; when used as a vehicle starting power source, its starting efficiency and reliability are higher than traditional batteries, which can completely or partially replace traditional batteries; as a vehicle's traction energy source, it can produce electric vehicles, Replacing traditional internal combustion engines, transforming existing trolley buses, etc.; in addition, it can also be used for energy storage of other electromechanical equipment.