Electrochemical potential memory device

Electrochemical potential memory devices were proposed by Takahashi and Yamamoto (1973) they have been extensively developed by Ikeda and Tada (1980) of the Sanyo Electric Company, Japan, and are commercially available. The device construction is... 

Fig. 11.34 Schematic diagram of an electrochemical potential memory device (Ikeda and Tada, 1980).

Much of the recent research in solid state chemistry is related to the ionic conductivity properties of solids, and new electrochemical cells and devices are being developed that contain solid, instead of liquid, electrolytes. Solid-state batteries are potentially useful because they can perform over a wide temperature range, they have a long shelf life, it is possible to make them very small, and they are spill-proof We use batteries all the time—to start cars, in toys, watches, cardiac pacemakers, and so on. Increasingly we need lightweight, small but powerful batteries for a variety of uses such as computer memory chips, laptop computers, and mobile phones. Once a primary battery has discharged, the reaction cannot be reversed and it has to be thrown away, so there is also interest in solid electrolytes in the production of secondary or storage batteries, which are reversible because once the chemical reaction has taken place the reactant concentrations can be... 

Because all electrochemical devices such as batteries, fuel cells, sensors, and electrochromics require an electrolyte, the potential applications for ionic conductors are enormous. In addition to these more conventional applications, solid electrolyte materials are investigated for use as electrochemical memory devices, oxygen pumps, gas phase electrolyzers, and thermoelectric generators. ... 

Electrochromic displays are simple electrochemical cells with an electrochromic material as one of the electrodes. A potential applied between the anode and cathode, typically less than 5 V, produces the desired color change. Once switched, the current between the anode and cathode diminishes. Most electrochromic displays have a memory (stay switched even if no potential is applied as long as the electronic connection between anode and cathode is broken), many on the order of hours. Thus, they are ideal for low-power applications. Unfortunately, many printed electrochromic devices are relatively slow. Speeding up the device requires a liquid electrolyte, which is difficult to manufacture and encapsulate in an inexpensive device. 

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