Battery Chargers are tremendously useful, allowing us to put power into rechargeable batteries and thus reuse them repeatedly without having to buy more for a long time. They are usually used in the home but variants can be found for power tools and various other devices that run on a local battery. The great thing is not just the saving on new batteries, but the fact that with spare charged batteries and the lack of need for a battery shop, chargers let us use our electrical devices wherever we need to and without a mains cable.
The standard battery charger is a box shaped unit that has slots for several household batteries. The most basic chargers simply put the mains electric current into the batteries, filling it constantly, which can cause overcharging and loss of quality if they are left in. They can also be found with timers that just charge for a set time and then shut off, preventing overcharging but generally only fitting the batteries they are sold for.
More advanced chargers monitor the current voltage of the battery, allowing them to see how much charge is currently held and only charge the battery as much as is needed. They can detect a full battery and switch to a trickle of power that just keeps it topped up, and should not overheat or overcharge. They can even be found in a super fast form, which usually has special batteries and a special charger that charges very quickly and has its own cooling system such as a fan. These are often sold with cameras and other personal battery powered equipment to allow a person more freedom.
Unfortunately some items that use batteries and stuck with their specific charger. Mobile phones are the most prevalent personal technology of our time, but they are charged by keeping the battery inside and plugging the unit into a wall socket with a specific adapter. This means that you need to have the adapter for full mobility. Some companies have addressed with charging kiosks that have a variety of plugs and let you pay for a single charging.
