The technical platform that made the Eco-Drive concept possible was the Eco-Drive caliber 7878 movement.
To store electrical energy the first Eco-Drive movements employed titanium lithium-ion rechargeable or secondary batteries. This battery type became available in the early 1990s, enabling an Eco-Drive 7878 movement to run 180 days on secondary power before requiring recharging via light exposure — a marked improvement in energy storage over previous light-powered watches. The movement also featured an "insufficient recharging" indicator.
In addition to the first three Eco-Drive models introduced in 1995, Citizen marketed numerous other Eco-Drive models during the 1990s, including the 6.05 mm (0.238 in) thick Eco-Drive Slim of 1996
Since 2009, Citizen has developed Eco-Drive Concept Models as technology demonstration and marketing tools. These Eco-Drive Concept Models are generally shown at exhibitions and produced in limited editions.[6][7][8] The Concept Model 2011 was the Eco-Drive SATELLITE WAVE that has a movement that can receive time synchronization signals from GPS satellites. This makes radio-controlled timing possible in remote areas that are not serviced by land based radio time signal stations.[9] In 2012 Citizen announced the Eco-Drive RING Concept Model. This watch features a ring-shaped solar cell surrounding the watch case sidewall
According to Citizen, by 2011 80% of their wristwatches featured Eco-Drive, and the company saw Eco-Drive type watches at the focus of new generations of watches.[12]
In 2012 Citizen offered over 320 Eco-Drive watch models in various types, styles and price ranges
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