Capacitors Blog

 Recent advances in electrochemical capacitors for energy storage open new opportunities for water desalination devices with high energy efficiency.

Existing technologies for hard, brackish and sea water desalination are highly energy consuming even in the case of the best available technology nowadays, Reverse Osmosis. In addition to this problem, the construction of desalination plants requires intensive capital expenditures.

Capacitive Deionization is a technological alternative to Reverse Osmosis provided it is a non-membrane and low-pressure process, which are possibly the two main drawbacks of the Reverse Osmosis technology. The Capacitive Deionization concept is schematically represented in the Figure. During the deionization cycle, an external electrical charge is applied on a pair of electrodes introduced in the feed water, this makes the ions dissolved in the water to migrate towards the electrode of opposite charge, where they are adsorbed. In the regeneration cycle, the electrical load of the electrodes is switched off, therefore adsorbed ions are released. If an electrical circuit is connected at this stage, an electrical current will be produced, just like in the discharge of a capacitor.

Early studies almost 40 years ago showed that Capacitive Deionization could be a feasible technology for low-cost water desalination, but by that time appropriate materials were not available yet. However, nowadays with the most recent advances in electrochemical capacitors, there are improved electrodes with performances good enough to bring the Capacitive Deionization systems from research laboratories to real life applications.

A capacitor or condenser is a passive electrical component consisting of an insulating, or dielectric, layer between two conductors. When a voltage potential difference occurs between the conductors, an electric field occurs in the insulator. This field can be used to store energy, to resonate with a signal, or to link electrical and mechanical forces. Capacitors are manufactured as electronic components for use in electrical circuits, but any two conductors linked by an electric field also display this property. The effect is greatest between wide, flat, parallel, narrowly separated conductors.

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Smaller density, four times the capacity, instant recharge... awesomeness.

You smell that? It’s the silicon-enriched aroma of new technology, and the source is nothing short of amazing! A small company in Cedar Park Texas known as EEStor has claimed it has developed a battery that will solve all life’s troubles. Well, all tech enthusiasts’ troubles anyhow.

Anyone who owns, or has owned, a portable device is familiar with how irritating battery technology is. Not only does it take hours to recharge the battery, but the capacity is often mediocre at best. Furthermore, they degrade over time and their charge is lost at a rate of several percent each month. The likes of NiCad, Li-ion, NiMH and Li-Po (to name a few) all suffer these cruel flaws, and are commonly found in everything from MP3 players to notebook computers. Fortunately for consumers, a new battery technology is emerging. One that will make power issues a thing of the past – the supercapacitor.