There are three commonly used types of AA and AAA batteries; alkaline, Nickel Metal Hydride (NiMH), and hybrid batteries. Each has its advantages and disadvantages. For starters, alkaline are one time use batteries that most consumers purchase. After the battery dies it is thrown out. NiMH are rechargeable and can be charged hundreds of times, but do not hold a charge for a long time. Ready to go hybrid are rechargeable and can hold 80% of its original charge for the first three months of its battery life. As you can see the preferred battery is the ready to go hybrid batteries. Hybrid last the longest and can hold their charge longer than other rechargeable batteries.
Alkaline batteries are one time use batteries that are thrown away after they are drained of power. These are the most common, as the manufacturers make more money if you continue to buy disposable batteries instead of rechargeable batteries. Alkaline are wasteful and leave a large amount of waste. Alkaline batteries are not easy to dispose of and are full of deadly chemicals. Proper disposal is not being enforced, a change that is necessary for the future of our planet. Alkaline are the cheapest, costing $ 4 a pack. That is why they are so common and used frequently. They are easy to acquire, very cheap, and do not need to be recharged. The drawback is that overtime you are spending more then you are saving.
Nickel Metal Hydride, NiMH for short, are rechargeable up to 1,500 times. This is equivalent to buying and using 1,500 alkaline batteries with a single NiMH battery. It is remarkable how environmentally friendly and cost efficient NiMH batteries are. Their capacities range from 1100mAh to 2900mAh at 1.2 Volts. The only drawback is their fast discharge rate. The downside to these batteries is their discharge rate, meaning they drain the rechargeable battery life quickly. They work great for passive electronics that are left sitting around untouched, such as clocks and watches. For electronics that are used frequently, cameras and MP3 Players, the battery will drain quickly and need to be recharged once again. Overall NiMH batteries are said to be more environmentally friendly than NiCd batteries and alkaline batteries.
Ready to go hybrid are becoming more prevalent with consumers. Shoppers are beginning to realize there added benefits of using hybrid batteries. Not only do the last longer than other batteries, but they are rechargeable. The strongest benefit of hybrid batteries is that they maintain 83% of the batteries capacity for eight months of use. This is unlike the NiMH batteries which lose their capacity rapidly. They are pre-charged and ready for use straight out of the package. Being able to recharge a battery can save you hundreds, even thousands of dollars annually. Only hybrid battery is the equivalent to one thousand throw away batteries. The drawback to hybrid batteries is that they have a peak capacity of 2200mA, lower than NiMH batteries.
Price wise NiMH and hybrid batteries cost the same amount, ranging from around $ 9 each pack. Alkaline batteries on the other hand are much cheaper, ranging around $ 11 each pack, but can only be used once. If you look at it from a long term point of view, you will save hundreds, if not thousands of dollars by using rechargeable batteries. Plus you will help save environmental resources for future use.
In summary, the optimal choice is to purchase ready to go hybrid batteries. If not then purchase NiMH batteries. Your last resort for desperate times should be alkaline batteries.