What are the commonly used NiMH batteries?


Nickel-metal hydride batteries are often used in our li […]

Nickel-metal hydride batteries are often used in our lives. They are more expensive and perform better than nickel-separated batteries. For lithium batteries, there are still some gaps in performance. In the process of using nickel-metal hydride batteries, we must master the most basic Simple common sense about NiMH batteries.

First of all, you must know what a nickel-metal hydride battery is. It is mainly composed of hydrogen ions and metal nickel. The standard name is metal hydride nickel battery. The nominal voltage is 1.2V, the termination voltage is 1.0V, and it is discharged at 0.2C until termination. After the voltage is reached, the constant current charging is started, and the hydrogen capacity is identified by the national technical supervision department. It is charged according to the 0.4C charging system and discharged according to the 0.2C discharge system. The full charge is used to identify the storage performance of the battery. After storage for 12 After one month, after fully charged, discharge at 0.2C, the time should not be less than 4h, overcharge performance: after charging at 0.4C, continue to charge at 0.1C for 48h, there should be no deformation, no leakage, no smoke, And so on, these are all brief descriptions by the hydrogen electricity national standard GB/T18288-2000.

For nickel-metal hydride batteries, we generally charge them fully, which is good for the battery. It can be charged more fully, and it is easier to activate active substances for better use. However, there are conditions in the process of full charging. The market The charger above will not be designed with such a small charging current (in terms of 3508 hydrogen, it should be 50mA). If you use an ordinary charger for 16 hours, either the charger will be cut off after it is fully charged, and the rest will be a waste of time, or after it is fully charged The trickle flow of the battery is too large to cause overcharge, but the ability of hydrogen battery to resist overcharge is much stronger than that of lithium battery. The concept of charging time of more than 10 hours is inherited from hydrogen battery, but it is no longer applicable to lithium battery. The specification has a provision for full charging, but it is conditional, and there is no corresponding provision for lithium batteries at all, but a pre-cycle is given before the test, and the pre-cycle charging is over when the constant current reaches 4.2V, and there is no subsequent lateral voltage compensation at all. During the electrical process, lithium batteries do not need so-called "activation".

If the NiMH battery is not used for a long time, a standard charge-discharge cycle must be done to store it with full power. After the hydrogen is fully charged, the voltage is nX1.45V. With the continuous improvement of the new process, a new mode is replaced. Charging and discharging to improve the performance of Ni-MH battery products will be released by the National Science and Technology Press in the near future, so that Ni-MH batteries can be better used.