The Lithium-ion Capacitor is a hybrid energy storage device, classified as an electrochemical capacitor, that combines the rapid charging, high-power capability, and long cycle life of a capacitor with the higher energy density of a battery.
General Capacitor [GC] is introducing a patented Li-Ion Capacitor [LIC] that offers higher voltage than conventional ultracapacitors and the highest energy density of any type of capacitor on the commercial market.
GC is currently producing the 3.8V LIC in 200F, 1100F, and 3000F cell.
Ultrathin LIC 1-10F cells are currently under development.
The GC 3.8V LIC 3000F can store up to 18 Wh/kg of specific energy and 30 Wh/L of volumetric energy density.
It is capable of 8 kW/kg of power density, with a maximum discharge current of 150 A, and has a lifetime of over 100,000 recharge cycles.
GC 3.8V LIC products operate in a range of 3.8 to 2.2 V and a temperature range of -40° to 65° C.
Higher Voltage and Energy Density
An LIC is composed of (+) activated carbon cathodes and (-) graphitic anodes. GC anodes are pre-doped with lithium, which lowers charge potential and results in an overall higher cell voltage. This process allows GC LICs to offer a maximum voltage of 3.8V compared to 2.7V of electric double-layer capacitors.
The GC 3.8V LIC is capable of 18 Wh/kg of energy density, while EDLCs are only capable of 6-7 Wh/kg.
Excellent Cycling Peformance
The GC LIC can perform over 100,000 charge-discharge cycles while retaining 80% of initial capacitance. Typically, rechargeable batteries are only capable of 500~1000 charge cycles.
Due to their high voltage and rapid discharge, LICs are well-suited to be used in tandem with batteries. In hybrid energy storage systems, Li-ion capacitors provide auxiliary peak power and prevent batteries from performing deep discharges. This improves overall system performance, efficiency, and lifetime.
LICs exhibit an average loss of ~5% voltage from maximum charge over a 3-month period.
EDLCs typically undergo a ~20% voltage loss after only 1-month.
Wide Temperature Range
GC 3.8V LICs are tested under extreme temperature conditions to simulate all possible applications. Testing includes environments of 65° C to simulate hybrid-electric vehicle engines and wind/solar farms; and freezing temperatures of -40° C to simulate arctic and aerospace operating conditions.
LIC technology is inherently much safer to use than lithium-ion batteries. Lithium-ion capacitors do not contain lithium metal oxide electrodes that can trigger thermal runaways as seen in Li-ion batteries.
LICs are safe, reliable, environmentally-friendly, and aren't as strictly regulated as lithium-ion batteries during shipping and transportation.