Batteries are used everywhere. Portable electronics, flashlights, clocks and toys are just a few of the devices that use batteries. Two commonly used batteries are alkaline and NiMH. Alkaline batteries are disposable batteries that are sold in common sizes like AA, AAA, C and D sizes. NiMH or Nickel-Metal-Hydride batteries are also sold in common sizes; however, they are rechargeable and can be used hundreds of times.
Alkaline and NiMH batteries are interchangeable; however, certain battery-powered devices perform better depending on the type of battery is used. Alkaline batteries are better used in devices that require a lower discharge rate. Devices like clocks and some toys will last longer with alkaline batteries than they would with NiMH. NiMH batteries perform much better than alkaline batteries in high discharge devices like digital cameras.
Alkaline batteries are one-use batteries that cannot be recharged or reused. NiMH batteries have the ability to be recharged and used multiple times. Alkaline batteries typically have high mAh power ratings compared to most NiMH batteries; however, for the alkaline battery to use its full potential, the discharge rate must be low. A typical NiMH AA battery will have 2300 mAh on average compared to an alkaline which will have an average of 2800 mAh. According to GreenBatteries.com, alkaline batteries are rated at 1.5 volts when fully charged, but quickly drop to 1 volt as the battery drains. NiMH batteries are consistent at 1.2 volts.
Alkaline and NiMH batteries each have their own unique set of benefits. Alkaline batteries, unlike NiMH, are readily available and are able to be used right away. They are typically inexpensive and can be stored for a long time before they are no longer usable. NiMH batteries are reusable; however, they must be charged before the first initial use. NiMH batteries can deliver large amounts of power quickly.
Alkaline and NiMH batteries have different strengths and it would be hard to say that one is better than the other. Alkaline batteries are typically inexpensive and will hold their charge for up to seven years in the package, according to Energizer. NiMH batteries will not hold a charge for much more than a month; therefore, it is important to charge them before you install them in your device. NiMH batteries are able to be recharged hundreds of times before they begin to degrade. NiMH batteries do cost more initially; however, repeated use and recharging will allow you to recoup the cost of the batteries.
A common misconception of NiMH batteries is that they retain a recharge memory if not properly discharged fully. NiMH batteries do not hold memory if they are not fully discharged and then recharged. Battery memory refers to some older types of rechargeable batteries that would only lose capacity unless they were completely recharged. Another misconception is that alkaline batteries will last longer if stored in the refrigerator. Alkaline batteries have a slow self-discharge rate and keeping them cool will not affect the life of the battery. NiMH batteries stored in the refrigerator will hold their charge for a significantly greater time than NiMH batteries stored at room temperature.