While rechargeable batteries have become a part of everyone’s daily life in various electronic gadgets like mobile phones, laptops, digital cameras etc, the consumption of disposable batteries is still high. Obviously, the consumers are still reluctant to replace these non-rechargeable batteries in many household devices by rechargeable batteries.

In 2005, SANYO asked hundreds of consumers if they knew about rechargeable batteries and why they still used disposable batteries. The major reason given by the consumers was that they were disappointed by the high self-discharge of rechargeable batteries. “Whenever you need them, they are drained and need to be recharged” was a common complaint about them.

This complaint about rechargeable batteries was reasonable, because at that time all manufacturers of rechargeable batteries focused their energies on increasing capacity and nobody seemed to care about the batteries’ discharge rate. Compared to alkaline batteries Ni-MH batteries had a relatively high self-discharge rate.

SANYO was the first company to act on this information from the consumers and developed a rechargeable battery with very low self-discharge: eneloop. While conventional Ni-MH batteries suffer from substantial self-discharge, eneloop batteries have a drastically reduced self-discharge.

The diagram above illustrates the difference between a conventional SANYO Ni-MH battery and an eneloop battery. A conventional Ni-MH battery loses 35% of its initial charge after 360 days of storage, while an eneloop battery loses only 15%. Some conventional Ni-MH batteries lose their residual capacity at an even greater rate; a loss of 1% per day of their initial charge is not uncommon.

This breakthrough in battery technology represents a strong counter to the argument that rechargeable batteries lose their charge too rapidly. eneloops can stored for months and still retain capacity levels that are nearly identical to their original ones. With eneloop there is no need to worry about charging batteries before use.

Finally, rechargeable batteries can now be used in applications that were previously designed for the use of alkaline batteries only, such as remote controls for a TV set. They may not last quite as long as alkaline batteries, but the difference in their cycle lives is almost negligible. More importantly, you can recharge it and use it over and over again.

eneloop can be used for a wide range of applications.