The Charging Method Of Lithium Battery

- Aug 13, 2018-

Now the mobile phone uses a lithium-ion battery, so there is no memory effect problem, and there is no need to activate. The first charge does not need to be flushed for more than 12 hours like nickel. It only needs to charge for about 4 hours. The life of the ion battery is only The number of times of charging is related, and the lithium-ion battery can be charged about 1000 times. Standby time is related to usage. However, selling mobile phones said that the previous three charging times should reach 12 hours. what happened?

1. How to charge a new battery

In the use of lithium batteries, it should be noted that after the battery is placed for a period of time, it enters a sleep state. At this time, the capacity is lower than the normal value, and the use time is also shortened. However, the lithium battery is easy to activate, as long as the battery is activated after 3 to 5 normal charge and discharge cycles, the normal capacity is restored. Due to the characteristics of the lithium battery itself, it is determined that it has almost no memory effect. Therefore, the new lithium battery in the user's mobile phone does not require special methods and equipment during the activation process. Not only in theory, but from my own practice, it is best to use a standard method of charging this "natural activation" method from the beginning.

For the "activation" problem of lithium batteries, many claims are: charging time must be more than 12 hours, repeated three times in order to activate the battery. This statement that "the first three charges have to be charged for more than 12 hours" is obviously a continuation of nickel batteries (such as nickel cadmium and nickel hydride). So this kind of statement can be said to be misinformation at the beginning. The charge and discharge characteristics of lithium and nickel batteries are very different, and it is very clear to tell you that all the serious formal technical information I have reviewed emphasizes that overcharge and overdischarge will make lithium batteries, especially liquid lithium. Ion batteries cause great damage. Therefore, charging is preferably done in accordance with standard time and standard methods, especially for ultra-long charging of more than 12 hours. Usually, the charging method described in the mobile phone manual is a standard charging method suitable for the mobile phone.

In addition, the lithium battery phone or charger will automatically stop charging after the battery is fully charged, there is no so-called “turbulent” charging that the nickel battery charger has for 10 hours. In other words, if your lithium battery is full, it will be white charger on the charger. And none of us can guarantee that the characteristics of the battery's charge and discharge protection circuit will never change and the quality will be foolproof, so your battery will be on the edge of danger for a long time. This is another reason why we oppose long charging.

In addition, on some mobile phones, after charging for more than a certain period of time, if you do not remove the charger, then the system will not stop charging, and will start the discharge-charge cycle. Perhaps the manufacturer of this approach has its own purpose, but it is clearly unfavorable for the life of the battery and the phone/charger. At the same time, long charging takes a long time and often needs to be carried out at night. In the case of China's power grid, the voltage at night is high in many places and fluctuates greatly. As mentioned earlier, the lithium battery is very delicate, it is more resistant to charge and discharge than nickel.

The ability to fluctuate is much worse, which in turn brings additional danger.

In addition, another aspect that cannot be ignored is that lithium batteries are also not suitable for over-discharge, and over-discharge is also disadvantageous for lithium batteries. This leads to the following problem.

2. When should I start charging during normal use?

In our forum, we can often see this statement, because the number of charge and discharge is limited, so the battery of the mobile phone should be recharged as much as possible. But I found an experimental table on the charge and discharge cycle of lithium-ion batteries. The data on cycle life are listed below:

Cycle life (10%DOD): >1000 times

Cycle life (100% DOD): >200 times

Among them, DOD is the abbreviation of depth of discharge. As can be seen from the table, the number of chargeables is related to the depth of discharge, and the cycle life at 10% DOD is much longer than that of 100% DOD. Of course, if you convert to the relative total capacity of the actual charge: 10% * 1000 = 100, 100% * 200 = 200, the latter's full charge and discharge is still better, but the former netizen's statement to do some correction: in normal In this case, you should have the reserve to charge according to the principle that the remaining battery power is used up and recharge, but if your battery is not likely to stick to the whole day on the 2nd day, you should start charging in time. Of course, if you are willing to carry it back It’s a different matter to get the charger to the office. And you need to charge to cope with the expected important events that will cause the communication to be busy, even if the battery still has a lot of power, then you only charge in advance, because you have not really lost "1" charge cycle life. That is, "0.x" times, and often this x will be small. The principle of recharging the remaining battery power is not to go to extremes. One of the more widely spread sayings like long charging is that "try to run out of battery power, it is best to use automatic shutdown." This practice is actually only a nickel battery, the purpose is to avoid the memory effect, unfortunately it is also circulating on the lithium battery. Someone has used the example of automatic shutdown since the warning of the low battery level of the mobile phone is still not used. As a result, the mobile phone in this example did not respond during the subsequent charging and booting, and had to be sent to the customer service for repair. This is actually caused by the battery being over-discharged and the voltage is too low, so that it does not have normal charging and power-on conditions.

3. the correct practice for lithium battery mobile phones

To sum up, my most important tips on the charging and discharging problems of lithium battery mobile phones in use are:

1. Charge according to standard time and procedures, even if it is the first three times;

2. When there is a low battery power prompt, you should start charging as soon as possible;

3. The activation of the lithium battery does not require a special method. The lithium battery will naturally activate during normal use of the mobile phone. If you insist on using the flow legend "the first three 12-hour long charge activation" method, it will not actually work.

Therefore, all the pursuit of 12 hours of ultra-long charging and the use of lithium battery mobile phones to automatically shut down are wrong. If you have done it in the wrong way, please correct it in time, maybe it is not too late.

Of course, in the case of good quality of the mobile phone and charger protection and control circuit, the protection of the lithium battery is quite guaranteed. So the understanding of the charging rules is the focus, and in some cases it is also possible to make some concessions. For example, if you find that the phone must be charged before you go to sleep at night, you can also start charging before going to bed. The point is that you should know what the right approach is and don't deliberately follow the wrong way.