A lithium ion capacitor (LIC) is a capacitor that uses a carbon-based material capable of absorbing lithium ions as the negative electrode material, and improves energy density by adding lithium ions to it, while using the principles of a general electric double layer capacitor.
The principle of charging and discharging differs between the positive electrode and the negative electrode, and the structure combines the negative electrode of a lithium-ion battery and the positive electrode of an electric double layer.
A type of asymmetric capacitor with a different positive and negative electrode principle, which combines the positive electrode of an electric double-layer capacitor and the negative electrode of a lithium-ion battery. While the positive electrode operates by the principal of physical, Electrical Double Layer, the negative electrode charges and discharges by the redox reaction of lithium. The high energy density compared to conventional capacitors is largely due to the fact that the pseudo electrostatic capacitance of the negative electrode is increased by pre-doping.
Lithium ion capacitor (LIC) is a new electric storage device that combines high power density and high energy density. Compared to similar electricity storage devices, electrical double layer capacitor (EDLC) and lithium ion battery (LIB), we introduce its characteristics.
Lithium Ion Capacitor | Electrical Double Layer Capacitor | Lithium Ion Battery | Lead Acid Battery | |
---|---|---|---|---|
Energy density | Medium (Higher at high current) |
Low | Very high | High |
Power density | High | High | Low (not good for rapid charge) |
Very low |
Rapid charge/discharge | in seconds | in seconds | in hours (Needs a charge control) |
in hours (Needs a refreshing charge) |
Internal resistance | Low | Low | High | Very high |
Low temperature performance | Good | Good | Very bad | Bad |
High temperature performance | Very good (up to 70℃) |
Good (up to 60℃) |
Very bad (up to 40℃) |
Very bad |
Self discharge | Small | Big | Small | Big |
Maintenance | Maintenance free | Maintenance free | Frequent replace required | Frequent replace required |
Lifetime (float / cycling) |
Long | Long | Relatively short | Short (sudden death occurs) |
Safety and flammability | High, flammable | High, flammable | Low, flammable (Self heat up / igniting) | High, not flammable |
Application | Very high power (Medium energy) |
Very high power (Lower energy) |
Medium power (High energy) |
Low power (High energy) |