Shipments of Sanyo's Eneloop rechargeable battery will soon hit 30 million thanks in part to the popularity of Nintendo's Wii games console.

The battery, which was launched in November 2005, received a boost last year when retailers in Japan promoted it to people buying the Wii. The Wii uses wireless remote controls and each requires two AA batteries. Many stores put Eneloop batteries right next to Wii consoles and peripherals on store shelves or at the cash register.

As a result, sales jumped by about 20 percent after the Wii launched, said Sanyo GM Hiroshi Shimozono.

Sanyo announced a tie-up with toy-maker Tomy today that will see three Eneloop AA batteries and a charger supplied with each i-Sobot, a humanoid robot toy that Tomy plans to launch later this year. Tomy said it chose Eneloop because the battery offered superior performance to other rechargeable batteries.

Eneloop is based on the same Nickel Metal Hydride (NiMH) chemistry as many other rechargeable batteries but, thanks to some changes in the way the battery is made, it can hold its charge longer. This allows Sanyo to charge the batteries prior to shipping them - something not possible with other rechargeable batteries.

A charged Eneloop will lose only 10 percent of its charge over 6 months and 15 percent over a year, according to Sanyo. An equivalent NiMH rechargeable from Sanyo loses 28 percent and 36 percent of its charge, respectively, over the same period, it said.

Sanyo has previously aimed at digital still camera users with its rechargeable batteries, but with Eneloop it has also been going after a wider range of products, and with success, said Hirohito Teraoka, general manager of the technical marketing department at Sanyo Energy Twicell.

"The release of Eneloop introduced many more first-time [rechargeable battery] users to the market," he said. "The release of Eneloop extended the use of rechargeable batteries to many home electronic devices."

Eneloop was born out of Sanyo's ‘Think Gaia’ project, a corporate-wide push toward more environmentally friendly products.

Sanyo is a major manufacturer of rechargeable batteries. It estimates its cells are used in around 45 percent of laptops, 60 percent of power tools and 35 percent of mobile phones and digital still cameras.

See also:

Nintendo Wii review