Correct use & charge of NiMH rechargeable batteries
First, let ‘s take a brief look at the difference of nickel-metal hydride batteries and other batteries.
1.Memory effect of Ni-MH battery
NiMH battery have the same memory effect as NiCd batteries, but they are much smaller than NiCd batteries. Therefore, it is not necessary to perform the discharge operation every time you charge (because the improper operation will damage the battery), you only need to fully charge and discharge once every three months to ease the memory effect.
2.Self-discharge rate of Ni-MH battery
Ni-MH batteries are 25 to 35% (months), nickel-cadmium batteries are 15 to 30% (months), and lithium batteries are 2 to 5% (months). NiMH batteries have the highest self-discharge rate, while lithium batteries have extremely low discharge rates compared to the other two types of batteries.
⒊Ni-MH battery charging method
Neither nickel-metal hydride batteries nor lithium batteries can withstand overcharge. Therefore, the PICKCUT control method of constant current charging of nickel-metal hydride batteries is the best charging method when the charging voltage reaches the maximum. Lithium batteries are best charged with a constant current and constant voltage. If they are charged with the Ni-Cad battery charger-DV control method, the service life of nickel-metal hydride batteries and lithium batteries will be affected.
4.Is the higher the capacity of Ni-MH battery the better?
Different types of batteries have higher capacity and longer usage time. Aside from volume and weight, of course, the higher the capacity, the better.
However, the same battery model has the same nominal capacity (such as 600mAh), and the actual measured initial capacity is different: for example, one is 660mAh and the other is 605mAh, so is 660mAh better than 605mAh?
The actual situation may be that the capacity is high because there is more in the electrode material that increases the initial capacity and reduces the stability of the electrode. As a result, after dozens of cycles, the high-capacity battery quickly fails and the capacity is low. Battery is still strong. Many battery cell manufacturers often obtain high-capacity batteries in this way. But the user's standby time after half a year of use is a mess.
The price of increasing capacity is sacrificing cycle life. It is impossible for manufacturers to truly “improve” battery capacity without the context of battery material modification.
Ni-MH battery charging method
The scientific charging method can prolong the service life of Ni-MH batteries.
① Under normal circumstances, new Ni-MH batteries have only a small amount of power. After purchasing, they must be charged and then used.
However, if the battery leaves the factory for a short time and has sufficient power, it is recommended to use it before charging. New nickel-metal hydride batteries generally need to be charged and used 3-4 times before their performance can be maximized.
② Although the memory effect of the Ni-MH battery is small, it is best to recharge it after each use, and it is fully charged at one time. Do not use it for a while and then recharge it. This is an important point of "extending life".
③ When charging, pay attention to the heat dissipation around the charger. Keep the battery clean when not in use, especially the contacts at both ends, and wipe it with a soft dry cloth if necessary. If not used for a long time, remove the battery from the battery compartment and place it in a dry environment.
④ After being stored for several months, the nickel-metal hydride battery will enter a "sleeping" state, and the battery life is greatly reduced. If the nickel-metal hydride battery has been stored for a long time, it is recommended to charge it with slow charging first. Generally, the voltage of Ni-MH battery is below 1.2V before charging, and the normal voltage is about 1.4V when fully charged. This can determine whether the battery is fully charged.
Batteries are a kind of chemical "power source" widely used in the world. They have the advantages of stable voltage, safe and reliable, low price, wide application range, rich raw materials and high recycling rate. They are the largest output and most useful of all types of batteries in the world. A wide range of batteries.
The development of science and technology, the improvement of the quality of human life, the crisis of petroleum resources and the deteriorating global ecological environment have formed the dual social background of rapid development of science and technology and industries in the field of new secondary batteries and related materials. The urgent market demand has led to the emergence of new secondary batteries. Among them, new secondary batteries such as high-energy nickel-cadmium batteries, nickel metal hydride batteries, nickel-zinc batteries, maintenance-free lead-acid batteries, lead cloth batteries, lithium-ion batteries, and lithium polymer batteries are favored and widely used in various countries, and form an industry and develop rapidly.
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