Today, people around the world are increasingly interested in the environment. There are many innovations that focus on preserving the environment. Electrical appliances that require electricity is now being designed to use energy sources that can be recycled, especially the portable electronic devices. Their main power source is called a battery that provides electrical energy to mobile phones, portable music players, portable computers, digital cameras, smartwatches, etc. These devices are often used continuously for a long time which requires a lot of energy. If the battery is disposable, it will require more and more batteries which will also produce more garbage to the earth. Therefore, in order to reduce such waste, rechargeable battery and charger have been used to reduce pollution on the planet as much as possible.
Type of rechargeable battery
Currently in the market, the rechargeable battery contain 2 types of chemicals which are Ni-Cd and Ni-MH. Each battery cell gives the different voltages starting from 1.2 V when fully recharged. It might also have a capacity of 1.4 V and will be gradually reduced to a constant at about 1.3 V. This can be used to replace standard batteries with 1.5 V capacity.
Ni-Cd (Nickel-Cadmium) is the first generation of rechargeable batteries to be used instead of conventional batteries. The capacity (current and electrical power supply) starts relatively low. In this type of battery, you need to keep using it until it is too exhausting to supply the power to the device, then it is time to get it recharged. This is because there is a problem called memory effect, which if charging the battery while the battery is not running out, the battery will provide energy as long as the last charge that makes it full. If charging like this frequently, you will find that the battery life will become shorter even if you keep charging it for a longer time.
Ni-MH (Nickel-Metal Hydride) is a popular rechargeable battery nowadays. This type of battery has much less memory effect problem than the Ni-Cd battery and the capacity is also much higher. But one disadvantage of Ni-MH is that it weighs more than Ni-Cd. However, this might be a good thing for buyers to easily distinguish between rechargeable Ni-Cd and Ni-MH batteries.
Apart from the type of rechargeable battery, we can categorize the type of charger as well. The type will be mainly divided by the charging current and time. The first type is a rapid charger or fast charger. It is a fast charging at 100% of the battery capacity. The second type is a quick charger, soft charger, or standard charger. It is also a fast charging at 20-50% of the battery capacity. The third one is a slow charger or normal charger. It charges at 10% of current capacity but is kind of rare in the market now because it takes a long time to fully charge.
Supplementary information of rechargeable battery and charger
The capacity of rechargeable battery and battery charger is measured by mAh (milliampere hour). The higher numbers of mAh means the greater power capacity. The bigger numbers indicate that it can be used longer under the same condition. For example, 2500 mAh battery means this battery can supply 2500 mA current in 1 hour. For the battery charger, you should use a charger be an auto cut-off when fully charged. Because we would not know how much power the battery has lost. If the battery is not fully charged, it will cause the battery to run out too quickly. Or if it is overcharged, the deterioration rate will be too fast. This is why automatic cut off circuit has been designed to check the fullness of the battery by keep checking the charging level until it has achieved the maximum capacity or switching to low level charging instead. Many charger models usually come with the LED light to inform the status to users.