What is a Lithium-ion capacitor?

# What is a Lithium-ion capacitor?｜Lithium-ion capacitor｜JTEKT CORPORATION Source: [https://www.jtekt.co.jp/e/products/capacitor/capacitor_about.html](https://www.jtekt.co.jp/e/products/capacitor/capacitor_about.html) [＞ Inquiries regarding products](https://www.jtekt.co.jp/e/support/contact_capacitor.html) ## What is a Lithium\-ion capacitor？ Capacitors are power storage devices that are classified as secondary batteries\.Various types of capacitors have been developed depending on the materials used, but there are generally two types of capacitors with large capacities: "Electric Double Layer Capacitors \(EDLC\)" and "Lithium\-ion Capacitors"\.  Comparison of power density and energy density for power storage devices [＞ Click here for glossary about electricity](https://www.jtekt.co.jp/e/products/capacitor/capacitor_about.html#id01) ## Features The feature of capacitors is that electricity goes in and out \(charges/discharges\) very quickly\.Compared to well\-known power storage devices \(lithium\-ion secondary batteries, lead\-acid batteries, etc\.\), the energy density is inferior, but the power density is excellent, the performance deterioration due to repeated charging and discharging is small, and the life is long\. ### Performance comparison table ◎Excellent、◯Good、△Average Lithium\-ion BatteryEDLCLithium\-ion Capacitor \(Conventional\)Energy◎△◯Power density△◯◯Service life \(number of charges/discharges\)△◯◯Operating temperature range \(℃\)\-20～60\-40～70\-30～70Operating voltage \(V\)～4\.30～2\.72\.2～3\.8 Lithium\-ion Capacitor \(Libuddy\)◯〇⇒◎ （Improved by increasing heat\- resistance）〇⇒◎ （Improved by increasing heat\- resistance）\-40～852\.2～3\.8 Libuddy has significantly improved power density and service life due to the wide operating temperature range\. [＞ Click here for glossary about electricity](https://www.jtekt.co.jp/e/products/capacitor/capacitor_about.html#id01) ## Principle and structure of Lithium\-ion capacitors Lithium\-ion capacitor combines the positive electrode of EDLC and the negative electrode of a Lithium\-ion secondary battery\. This achieves higher energy density than general capacitors and higher safety than general Lithium\-ion secondary batteries\. Lithium\-ion BatteryEDLCLithium\-ion Capacitor \(Conventional\)Internal structure[ Click to enlarge](https://www.jtekt.co.jp/e/products/capacitor/capacitor_about.html#)[ Click to enlarge](https://www.jtekt.co.jp/e/products/capacitor/capacitor_about.html#)[ Click to enlarge](https://www.jtekt.co.jp/e/products/capacitor/capacitor_about.html#)Charge / discharge mechanism\+：Lithium chemical reaction \-：Lithium insertion / removal脱\+：Electrolyte ion adsorption / desorption \-：Electrolyte ion adsorption / desorption\+：Electrolyte ion adsorption / desorption \-：Lithium insertion / removalFeaturesEnergy \(Wh/L\)200～4003～610～20Power density \(W/kg\)500～2,0001,000～4,5001,000～3,500Cycle life \(cyc\.\)1,000～3,000Over 100,000Over 100,000Operating temperature limit \(℃\)\-20～60\-30～70\-30～60 Lithium\-ion Capacitor \(Libuddy\)[ Click to enlarge](https://www.jtekt.co.jp/e/products/capacitor/capacitor_about.html#)\+：Electrolyte ion adsorption / desorption \-：Lithium insertion / removal137,000Over 1 million\-40～85     There are two types of capacitors, a laminated type and a can type\.JTEKT uses the laminated type \(shown below\)\.  [＞ Click here for glossary about electricity](https://www.jtekt.co.jp/e/products/capacitor/capacitor_about.html#id01) ## Manufacturing method of Lithium\-ion capacitor Lithium\-ion capacitors are manufactured in much the same process as Lithium\-ion batteries\.  General method for manufacturing lithium\-ion capacitors ## Glossary about electricity Current \(A\)The number of electrons flowing per secondVoltage \(V\)The difference in potential between two pointsWatt \(W\)Amount of electrical energy that can be output per secondWatt\-hour \(Wh\)Total electrical energyInternal resistance \(mΩ\)Resistance of energy storage devicesC\-rate \(C\)A value that represents the ease of outputting powerJoule heat \(J\)Heat generated when a current flows through a conductorPrimary batteryBatteries that can only be discharged \(cannot be charged\)Secondary batteryRechargeable batteries \(can be used repeatedly\)Float chargingHow to charge at a constant voltagePower density \(W/L, W/kg\)Power by unit volume or massEnergy density \(Wh/L, Wh/kg\)Electric energy by unit volume or mass ## Link ## Download - [Materials about JTEKT's Capacitor](https://www.jtekt.co.jp/e/products/pdf/capacitor/capacitor_catalog_e.pdf) [](https://www.jtekt.co.jp/e/support/contact_capacitor.html)