ПРОДУКЦИЯ :
Лестницы
Ограждения
Входные группы, навесы, козырьки
Стеклоконструкции
Фурнитура для стекла
Ковка
Литье
Деревообработка
Тросы н/ж
Судостроение
Огнеупоры

Where Do Batteries End and Supercapacitors Begin?
Comparing batteries and supercapacitors
The different mechanisms of capacitive energy storage are illustrated...


Electrochemical measurements can distinguish between different types of energy storage materials and their underlying mechanisms.

Batteries keep our devices working throughout the day — that is, they have a high energy density—but they can take hours to recharge when they run down. For rapid power delivery and recharging (i.e., high power density), electrochemical capacitors known as supercapacitors are used. One such application is regenerative braking, used to recover power in cars and electric mass transit vehicles that would otherwise lose braking energy as heat. However, supercapacitors have low energy density. Batteries and supercapacitors both rely on electrochemical processes, although separate electrochemical mechanisms determine their relative energy and power density.

Comparing batteries and supercapacitors.(Ato D) The different mechanisms of capacitive energy storage are illustrated. Double-layer capacitance develops at electrodes comprising (A) carbon particles or (B) porous carbon. The double layer shown here arises from adsorption of negative ions from the electrolyte on the positively charged electrode. Pseudocapacitive mechanisms include (C) redox pseudocapacitance, as occurs in hydrous RuO 2 , and (D) intercalation pseudocapacitance, where Li + ions are inserted into the host material. (Eto H) Electrochemical characteristics distinguish capacitor and battery materials. Cyclic voltam-mograms distinguish a capacitor material where the response to a linear change in potential is a constant current (E), as compared to a battery material, which exhibits faradaic redox peaks (F). Galvanostatic discharge behavior (where Qis charge) for a MnO 2 pseu-docapacitor is linear for both bulk and nanoscale material (G) ( 13, 14), but a LiCoO 2 nanoscale material exhibits a linear response while the bulk material shows a voltage plateau (H) (8).

During the past 5 to 7 years, the energy storage field has witnessed a dramatic expansion in research directed at materials that might combine the high energy density of batteries with the long cycle life and short charging times of supercapacitors. However, the blurring of these two electrochemical approaches can cause confusion and may lead to unwarranted claims unless careful attention is paid to fun-damental performance characteristics.

Read More about Batteries and Supercapacitors

 
< Пред.   След. >


MRC ltd. / Kiev MATERIALS RESEARCH CENTRE    
www.dom.ua    

MRC Ltd. Центр Материаловедения
г. Киев, ул. Кржижановского 3
Телефон: +38 (044) 233-24-43
Телефон: +38 (044) 237-71-87
Fax: +38 (044) 502-41-49
E-mail:
Мы работаем ПН - СБ с 10:00 до 18:00
Лицензия Creative Commons

Фотографии проектов реализованных компанией MRC TM "ДОМ", а также статьи и видеозаписи публикуются на условиях лицензии Creative Commons Атрибуция — С сохранением условий
(Attribution-ShareAlike) 3.0 Unported. Вы можете бесплатно копировать, распрострянять, изменять материалы с обязательной ссылкой на автора.

Яндекс цитирования  
0.17