Sanyo Eneloop AAA NiMH Pre-Charged Rechargeable Batteries 4 Pack (Discontinued by Manufacturer)
With normal rechargeable batteries it made sense to charge them just before you wanted to use them. Otherwise, there was too much risk that the battery would not provide full power when needed due to degradation of stored power. Therefore there was a checkpoint on every vacation checklist:  Charge batteries. Then the endless wait until the batteries are finally charged...even the most advanced and most expensive chargers typically take at least 15 minutes. This can be very long 15 minutes, if the taxi is waiting at the door.Now you can forget all this. Charge the eneloop, whenever you have time for it and store them. The extremely low self-discharge of eneloop batteries saves you from all the charging stress.When you use eneloop in your houshold equipment, spend some extra money and purchase a set of spare eneloops. Keep these spare eneloops stored in a charged state and you will always have fresh batteries at hand whenever you need them!More Features Than Typical Ni-MH BatteriesThe main advantages of Ni-MH rechargeable batteries exist also in the eneloop:Approximately 4 time more shots than with alkaline batteriesHigh performance even at low temperatures    (down to  –5 °C) during your winter vacationRechargeable and therefore cheaper on the long runGiven these advantages, there are however also some disadvantages to typical Ni-MH batteries which made consumers reluctant to exchange their disposable batteries for rechargeables:After purchase, rechargeable batteries have to be charged before they can be used.Rechargeable batteries lose stored energy quicklyContinous/frequent charging ( without conplete discharge ) can destroy the batteryThe charging process can take a long time and rapid chargers are expensiveAll these negative attributes have one root-cause: self-discharge.  Self-discharge means that a charged battery slowly discharges itself without any equipment consuming any current.  This is the reason for rechargeable batteries being sold in a discharged state. And this is the reason that keeping charged batteries for some time did not make any sense--When you needed then, the energy was gone.Immediate Use Like a Disposable BatteryBecause the eneloop has a very low self-discharge, Sanyo can ship the batteries to retailers in a charged state.  This means the consumer purchases a charged battery, which can be used immediately.  The eneloop is therefore as user-friendly as any disposable battery.