NiMH batteries have become popular for powering many electronic devices. They come in high capacity and lower capacity sizes. NiMH batteries are rechargeable and can be recharged using a standard NiCad battery charger or with a charger specially made for them. If a NiCad charger is used it will take longer to get a full charge since NiCads have a lower capacity. NiMH chargers are obtainable in what is known as smart charge or in timer controlled types. The timer controlled charger can be set to charge for a fixed length of time and will then shut off. Smart chargers do not charge for any fixed period but rather keep charging till the battery is completely charged before shutting off.
You might ask why everyone does not use a smart charger. The simple answer is that they are considerably more complex in construction and as a result cost more. So some users will opt for the fixed time charger so as to save some money. There is some saving to be made on the purchase price but there can be problems, due to partial recharging, as the timer shuts down the charger before a full charge has completed. This is annoying and for this reason most users will be well advised to get a smart charger at the somewhat higher price.
However if only lower capacity batteries are to be used a fixed time charger can perform this function quite well. For high capacity batteries a smart charger is definitely the best choice buy lsd.
Solar powered battery chargers are available and these will recharge your batteries where no power source is present. They are very useful if you are camping outdoors but the charging rate is quite low so that a long time is needed to fully charge a battery. They definitely have a use for anyone who cannot get to a power supply to recharge batteries but otherwise a smart charger is a better choice.
Several battery companies now make low self discharge batteries. These can keep 70% to 85% of their capacity when stored for a year at room temperature. In the same period of time ordinary NiMH batteries may lose 50% or more of their charge. LSD NiMH batteries are rechargeable just like normal batteries and can be recharged using the same battery chargers.
Their main difference is much longer shelf life and a higher price. These LSD batteries can be charged up to 1000 times which is double the figure for ordinary NiMH batteries. This makes them very economical for long term usage.
To be certain that you are really buying LSD batteries you should look for the specifications to be printed right on the battery casing. Some suppliers have been known to repackage standard batteries and label them LSD when they are not. It is essential to look for the specifications on any rechargeable battery in order to be sure you are buying the type of battery you want.
Consumers who make a lot of use of battery powered devices will find that rechargeable batteries, although more expensive initially, will provide huge savings over the cost of purchasing hundreds of standard batteries.
The well known Eneloop battery made by Sanyo has been brought out in a new version which can keep 75% of its charge for a period of three years, and can take up to 1500 recharges. Rechargeable batteries probably will continue to improve in future years.