First, it depends on the battery its voltage, amperage and capacity. The higher these indicators, the longer the battery will last. Second, the rate of discharge is affected by ambient temperature – at high temperatures the battery life is significantly reduced. Thirdly, much depends on electronics that uses batteries – more complex machines faster use of their potential. And fourth, they tend to self discharge over time. The rate at which batteries discharge by themselves, depends on the same factors as when using it.
If the village unit charger, then it should be replaced. Replacement of batteries is not difficult, because each portable electronics, there are special signs allowing you to replace the battery correctly is the signs "+" and "-". These same symbols on the batteries. To replace batteries, it is required to match the same marks on the unit or the charger. If the contacts are mixed up, then camera work, natural, will not. In addition, it may simply break.
There are batteries of two types – disposable and battery- ing. The first cannot be repeatedly recharged, and so they should be disposed after use. And the battery can be charged every time they sit down. Of course, always use the same batteries will not work because they also have an expiration date. It depends on what battery has a certain number of charge cycles, so over time you still have to replace them with new ones. Rechargeable batteries initially are very long – from several weeks to months. But after some time their charge lasts for a couple of hours. It depends on the same conditions as those of conventional batteries. Replacement of such devices is the same as that of conventional batteries.