In these times, rechargeable batteries have been opening up space in the market due to the technological explosion we are experiencing. Audio players, digital cameras, remote controls, watches, etc.
But they were very expensive and polluting and those two aspects had to be solved.
There are currently 2 types of batteries:
1/ Ni-Cd (Nickel Cadmium) batteries. They are not recommended because they suffer from the so-called "memory effect", which means that if you charge them and they are half full, the half you had will no longer be useful, and you would only have the other half active. This greatly shortens their useful life, and you have to be very careful to discharge the batteries before charging them.
2/ The Ni-Mh ones They are currently the most popular, and vary in price and manufacturer. They do not have the memory effect. Their price depends on their capacity.
On a battery you see 2 numbers, the first one is generally 1.2v which means that the battery gives 1.2 volts of power. The other one goes from 1,200mAh to 2,400mAh. This is the capacity of the battery, and it is what makes it more or less expensive. This number indicates the power that the battery gives for one hour without discharging. A 2000mAh battery will give 2000mA for one hour or, in other words, 1000mA in 2 hours or 500mA in 4 hours. Thus, a 2400 mAh battery will last twice as long as a 1200mAh battery.
Just as important as good batteries is a good charger. Batteries are damaged by charging them too quickly, excessively or with temperature changes. Ideally, you should have a charger that allows you to adjust the charging intensity, but they are usually very expensive. Otherwise, always choose a slow-charging charger.
It is also important to know that a battery does not reach its maximum capacity until it has gone through a series of initial cycles. These initial cycles are what will determine the useful life of the battery.
Battery care:
1st Never use up batteries "to the max", they will break.
2. It is best to charge the first 10 batteries completely. Charge them completely and discharge them until the device you are using them on turns off, then do not turn it on again or the batteries could “dry out”. Then charge them and when they are fully charged again, use them until they are discharged. This will happen 10 times. After this, you can charge them however you want.
3. Try not to mix different batteries.
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