When it comes to choosing a battery charger, there are so many options that it can be intimidating to choose among them. Following a few rules will guarantee that you choose a battery charger that will meet your needs and provide top quality service for years to come. A classic battery charger can handle either NiMH or NiCad batteries. A NiMH charger usually works with NiCad cells, but not vice versa. Most battery chargers are designed to work with AA or AAA batteries.
Certain electronic products require a special format battery charger, which is usually provided by the manufacturer. The average battery charger has a capacity of either four or six batteries. Ideally, you should have at least an extra pair of charged batteries on hand at all times, so make sure your charger can handle the load.
The typical battery charger is powered via an AC outlet. Smaller units plug directly into the outlet, making them extremely convenient for people on the go. Because they are designed with travelers in mind, these chargers usually work with both 100 and 220 volt outlets without the need for an adapter. Cheaper chargers require an external converter in the form of a power brick, which sends electricity to the charger via a power cord. This type of charger is much cheaper but also inconvenient, and it usually cannot handle 220 volts unless an expensive adapter is added.
One feature worth spending extra money on is a charger control. An expensive battery charger has an intelligent microprocessor that switches the charger off when the batteries are fully charged. It can also recognize how much charge is originally in the batteries and only add whatever's needed. Cheaper chargers, on the other hand, charge batteries for a fixed length of time, which can overcharge the battery and shorten its life. A simple LED is typically used to indicate when the charge cycle is complete.
The cheapest battery charger available will run just under 10 US dollars (USD), while top-quality models can cost up to 50 USD. Generally, the faster and more flexible a charger is, the more expensive it will be. The main factor that affects price is charge time - the faster a battery charger works, the more expensive it is. The fastest time available is just under sixty minutes, while the average charger takes seven to ten hours to fully charge a NiMH battery. If time is not important, choose the battery charger that offers the most features rather than the most expensive one.