Electric Double Layer Capacitors (EDLC), Supercapacitors

Part Number	Description / PDF	Quantity
850617030001 Würth Elektronik Midcom	CAP 3F -10% +30% 2.7V T/H	889
850617021005 Würth Elektronik Midcom	CAP 15F -10% +30% 2.7V T/H	0
850617022002 Würth Elektronik Midcom	CAP 50F -10% +30% 2.7V T/H	0
850617021001 Würth Elektronik Midcom	CAP 5F -10% +30% 2.7V T/H	521
850617021002 Würth Elektronik Midcom	CAP 7F -10% +30% 2.7V T/H	243
850617022001 Würth Elektronik Midcom	CAP 25F -10% +30% 2.7V T/H	61
850617021004 Würth Elektronik Midcom	CAP 10F -10% +30% 2.7V T/H	92

Electric Double Layer Capacitors (EDLC), Supercapacitors

1. Overview

Electric Double Layer Capacitors (EDLC), commonly referred to as supercapacitors, are electrochemical energy storage devices that bridge the gap between conventional capacitors and batteries. They store energy through electrostatic charge separation at the electrode-electrolyte interface, offering high power density, rapid charge/discharge cycles, and exceptional cycle life (up to 1 million cycles). Their importance in modern technology lies in enabling energy-efficient systems for applications requiring burst power, energy recovery, and backup power solutions.

2. Main Types and Functional Classification

Type	Functional Features	Application Examples
EDLC (Carbon-based)	High power density, long cycle life, low energy density	Regenerative braking systems, UPS
Pseudocapacitors	Higher energy density via redox reactions, moderate cycle life	Portable electronics, grid energy storage
Hybrid Supercapacitors	Combines EDLC and battery materials for balanced energy/power density	Electric vehicles, renewable energy systems

3. Structure and Composition

A typical supercapacitor consists of two activated carbon electrodes separated by a porous membrane, immersed in an electrolyte (aqueous, organic, or ionic liquid). The electrodes are coated on current collectors (usually aluminum foil), and the entire assembly is enclosed in a hermetically sealed metal or polymer casing. Advanced designs incorporate graphene or carbon nanotubes to enhance surface area and conductivity.

4. Key Technical Specifications

Parameter	Description & Importance
Capacitance (F)	Determines charge storage capacity (range: 1 F to 5000 F)
Rated Voltage (V)	Limits operational voltage (2.5 V 3.0 V per cell)
Equivalent Series Resistance (ESR)	Affects power delivery efficiency (low ESR enables high pulse currents)
Energy Density (Wh/kg)	Typical range: 5 50 Wh/kg
Power Density (kW/kg)	Typical range: 1 10 kW/kg
Cycle Life	Exceeds 100,000 cycles with minimal degradation

5. Application Fields

Consumer Electronics: Smart meters, LED flashlights
Automotive: Start-stop systems, kinetic energy recovery systems (KERS)
Industrial: Robotics, backup power for PLCs
Renewable Energy: Solar/wind energy storage, grid frequency regulation
Transportation: Trams, buses, and hybrid vehicles

6. Leading Manufacturers and Representative Products

Manufacturer	Product Series	Key Specifications
Maxwell Technologies (Tesla)	BoostCap BC Series	10 F 3400 F, 2.7 V, ESR < 0.5 m
Panasonic	Gold Capacitor Series	5 F 1000 F, 3.0 V, 10-year lifespan
Skeleton Technologies	SkelCap Series	1200 F 5000 F, 2.85 V, 40 kW/kg power density
Samsung SDI
Supercapacitor Modules	50 F 2000 F, automotive-grade durability

7. Selection Recommendations

Key considerations include:

Application Requirements: Prioritize power density for pulse applications or energy density for long-duration backup
Voltage Matching: Use cell-balancing circuits for multi-cell stacks
Operating Environment: Select electrolytes suitable for temperature extremes (e.g., ionic liquids for -40 C to 85 C)
Lifetime Cost: Evaluate cycle life versus initial cost (e.g., EDLCs outlast batteries in cycling applications)

Industry Trends and Future Outlook

Emerging trends include:

Development of graphene-based electrodes to double energy density
Integration with IoT devices for smart energy management
Growth in automotive applications driven by EV and 48V micro-hybrid systems
Adoption of aqueous electrolytes for safer, low-cost energy storage
Hybrid supercapacitor-battery systems for renewable energy grids

The global supercapacitor market is projected to grow at 20% CAGR (2023 2030), driven by demand in transportation and renewable energy sectors.