Sanyo today announced the release of new, upgraded AA- and AAA-size "eneloop" rechargeable batteries, which can be recharged approximately 1,500 times, according to the company.
The latest breakthrough allowing "eneloop" to be recharged up to 1,500 times has been realized by applying newly-developed recharging technologies. In addition, to embody the concept of a "Clean Energy Loop", the batteries are pre-charged at the factory using clean energy generated from renewable solar power as a part of the Green Power Certification System. As the new "eneloop" batteries hit the market, updated "eneloop" branded chargers and charger sets will also be entering the market.
With the ability to recharge the battery more times, the new "eneloop" is both more economically competitive, reducing the cost of usage per charge from the conventional model?s approximately 4 yen to 2.5 yen and enhanced in environmental awareness as it means the amount of overall battery waste will be reduced.
The durability of SANYO?s original "super-lattice alloy," a negative-electrode material used in "eneloop", has been enhanced by homogenizing the crystalline structure (a reduction of crystals with an irregular atomic order is irregular) as well as improving its composition (the ratio of constituent element) to reduce the deterioration of the super-lattice alloy by repeated charge and discharge.
A new additive to the negative electrode material, "super-lattice alloy", and a new additive coating technology was developed. By protecting the alloy surface, deterioration of the "super-lattice alloy" by repeated use can be reduced.
The new "eneloop" also adopts the same strong/thin outer case used for SANYO?s high-capacity AA-size rechargeable batteries, the "Ni-MH2700 Series." This improves the internal cell space efficiency and optimizes the balance of battery components, leading to an increase in the number of times a battery can be recharged.
Rechargeable batteries typically have a "self-discharge" characteristic which gradually reduces charged energy over time. This is considered the downside of typical rechargeable batteries, as it renders them inconvenient since they are unusable immediately after purchase, requiring the batteries to be charged to start using them and recharged if they have been left on the shelf for a period of time. Since "eneloop" batteries have a low self-discharge rate, they can be pre-charged and usable immediately after purchase, like dry cell batteries. This new "eneloop" battery continues this tradition, and a fully-charged "eneloop" will be "ready for use off the shelf even after 3 years" of storage, according to Sanyo. By using SANYO?s original "super-lattice alloy" for negative electrode material and improvement of materials and structure, a fully-charged new eneloop battery can maintain "approximately 75% of charged power even after 3 years", ensuring that power is available when needed.
In accordance with the Green Power Certification System, the new "eneloop" batteries will be charged by "green power" from photovoltaic generation, Sanyo added.