App note: Lithium Ion Capacitors: An Effective EDLC Replacement

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Hybrid capacitor of EDLC and LIB, Lithium Ion capacitors from TAIYO YUDEN offers solution to conventional EDLC lesser characteristics. Link here (PDF)

EDLCs were first created in Japan in the 1970s and began appearing in various home appliances in the 1990s. Since the 2000s, they have been used in mobile phones and digital cameras. EDLCs are typically used to protect against sudden momentary drops or sudden interruptions in power. They can instantaneously output large amounts of power, while a battery cannot. They are frequently used as backup power sources in servers and storage devices for integrated circuits, processors, memory and more.

While EDLCs are intended to be backup power sources, conventional EDLCs suffer from a phenomenon known as self-discharge, where the capacitor will gradually lose its charge over time. Self-discharge can occur more rapidly during exposure to high temperature environments. The extremely low self-discharge of an Lithium Ion Capacitor, even in high heat environments, ensures a long-lasting charge.

Supercapacitor Uses No Carbon

Supercapacitors have found a myriad of uses due to their ability to rapidly charge and then deliver the power efficiently. Currently, production of supercapacitors requires materials made out of carbon which requires high temperatures and poses other manufacturing difficulties.

Researchers announced a new type of supercapacitor that uses no carbon and could have advantages over conventional technologies. The new research focuses on metal-organic frameworks, or MOFs. This material is extremely porous with a sponge-like structure. Since supercapacitors require large surface areas, that makes MOFs an interesting material for that application. However, MOFs are not very electrically conductive, which is a disadvantage.

The team has used a conductive MOF to create a supercapacitor and without any optimization, it already performs as well as conventional units in key areas of performance. By experimenting with other MOFs and modifying other characteristics, the researchers think they can produce superior devices. Although the material costs more than carbon, the processing for it is less expensive, which could be a factor in making the devices affordable.

If MOFs are too exotic for you, maybe try dog hair. Or, do your experiments while enjoying fresh breath.


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App note: Enhancing cellphone battery performance during GSM pulses through the use of a parallel supercapacitor

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Low ESR and ESL supercapacitor paralleled to cellphone batteries can react more quickly to the demanding power required by GSM pulses. A great appnote read from AVX, link here (PDF)

With the constant addition of features and functionality, battery life and reliability are becoming increasingly vital to those who rely on their smartphones. The transmission signal requires quick pulses of current from the battery, potentially causing the instantaneous voltage of the battery to drop below the phone’s minimum voltage of operation. This may cause the power to the battery to be temporarily interrupted. A series of tests were performed on multiple battery chemistries to determine the beneficial effect of placing an AVX supercapacitor in parallel with the battery, to improve the life of the battery as well as the quality of power provided from it.