There are also some companies that leave it to the consumer to use replaceable consumer batteries. For these, it is important to choose the correct battery type such that your equipment works in the best possible way and to reduce unnecessary costs. There are many websites that you can read up on to know about battery choices. But they are usually rather technical and they assume that you have some basic physics knowledge.
A very comprehensive write up. Very long also - http://batteryuniversity.com
A simple table comparing common battery types - http://michaelbluejay.com/batteries/
A collection of battery/electronics guides. Also with an awesome database of battery capacity, characteristics of many brands and models - http://www.candlepowerforums.com/vb/showthread.php?133440-Flashlight-Electronics-Batteries-Included-Threads-of-Interest
First things first. There is no such thing as "the best battery" for everything unless you don't mind spending on the most expensive batteries and not using them to their max potential. I'll start from the most expensive to the cheapest non-rechargeable followed by rechargeable batteries
Non-rechargeables
1. Lithium
Dominated by Energizer, this type of battery has the best performance amongst other non-rechargeable for high drain devices. They are have extreme long term reliability and wide temperature tolerance. Downside is, they are damn expensive and costs as much as rechargeable batteries.
Best for: Devices that are expected to use up batteries within hours or less (cameras, video cameras, flash units, high power torch lights). Since they are so expensive, it makes sense to use them as backup batteries when your rechargeables are drained. Otherwise, use them for devices that you are likely to depend your life on. Coin size lithium batteries are also used in watches.
Price: About $5-7 a piece for AA and AAA in NTUC.
2. Alkaline
Offered by several brands. Cheaper brands are likely to have lower capacity. For example, I bought a pack of 10 AA batteries from IKEA at $2.50. According to tests done by forumers of candlepowerforums, they do have significantly less capacity than Energizer ones. But that is ok since they are so cheap! Long time ago, battery powered devices use very little power and alkalines were amazing. But now, with gadgets becoming smaller and requiring higher power, alkalines have not caught up with the demands of current day consumer electronics. Although they are supposed to have comparable or even more energy than Lithium batteries, their capacity decreases proportionally to how fast you drain it. Alkalines become less and less value for money the faster you drain them. Using them to power digital cameras is just a spectacular waste of money. However, they do have the tendency of leaking after keeping for a long time and may corrode the metal parts of your stuff.
Best for: Devices that run intermittently and have really low current requirements. Things like remote controls, clocks, radios, and stuff that are expected to last for weeks and months (or more than ~10hours of continuous use) on a single set of batteries. This is the only way to make full use of the high capacity. However, don't put them in devices that you may forget about.. because they may leak and destroy it.
Price: About $1-2 a piece for AA and AAA usually. Cheaper brands are fine since you are using them for low power and non-critical devices.
3. Carbon Zinc
Usually marketed as "Extra heavy duty" batteries. This is one of the oldest type of battery available and also used to serve devices of its time. In the 21st century, carbon zinc is super light duty! Again, they are suitable for devices that are suitable for alkalines, except that they have lower capacity then them. The only reason why I have Carbon Zinc batteries in my possession is because they came with things I bought. They are a good alternative for alkaline for bigger sized batteries such as the C and D size if you don't want to pay for an alkaline equivalent. But then again, I rarely have any devices that use such large batteries anymore. Maybe boomboxes? Who uses them now anyway? Do you even know what they are? Gosh, I am old.
Price: Depends on the shop selling them. They are supposed to be very cheap. I don't have any prices for reference.
Rechargeables
A. NiMH types
These are commonly available. The capacity goes up to about ~2500mAh for AA size but don't always believe what the label says. Most companies have the tendency to lie about their rated capacity and their batteries almost never achieve the claimed capacity. Until one day, a company decided to be honest about their rated capacity. Till now, Sanyo is the only company that is truthful about their battery capacity. Their "Eneloops" line of low self discharge batteries (meaning that you can charge them up and leave the batteries alone for a year or more and they will still retain a significant portion of the charge. The change in design brought about more than just low self discharge, but also a more resilient battery that lasts significantly more charge cycles than other brands (1500 cycles compared to the usual 500 cycles). To me, that is quite an improvement because their batteries cost the same as other brands and yet they offer so much more. Forumers from candlepowerforums swear by it.
Best for: This is probably the most versatile battery chemistry. Unlike alkalines or carbon zinc, this chemistry can take repeated high power usage without much loss in usable capacity, making them a good choice for cameras and high power torch lights. Although this is very good, they still need proper care in order to achieve their longevity and performance. Be sure not to drain the batteries completely by recharging them once you know they are getting weak and invest in a good charger that can sense when the batteries are full. Avoid 15min fast chargers. And no, there is no need to insist on draining it very low before charging it.
Price: about $5 a piece (AA)
B. Lithium-ion
These batteries are usually found in laptops, handphones and electric vehicles because they have the highest energy density, which allows them to store a lot of energy without being too heavy. These are not sold in its basic form, but rather, they are sold as battery packs and internal batteries because they require more care than NiMH batteries. They may explode if treated improperly, hence, most consumer products have safeguards in place to minimize the chance of this happening.
To take care of this battery type, try not to drain it too low. Once your computer or phone reaches 20%, try to charge it up already. Don't wait till reaches 5% or lower. This is called "deep discharge" and it is really bad for the battery. These batteries are supposed to last 300-500 cycles if you take care to minimize the number of times the battery undergo deep discharges.
In general, rechargeable batteries make a lot more sense than non-rechargeables because they perform well and can be charged so many times that it more than makes up for the higher initial cost. However, they need to be taken care of. The user must know how to treat it in order to reap the benefits.
