Some tips on lithium battery

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★★Reasons for the expansion of lithium battery and cell phone battery during use and analysis:
If the battery has been used for a long time, it will not expand normally. The reason for the battery expansion is that the charging time is too long. It will not affect the use, but the standby time will be shorter and shorter. Causes of Heat Expansion of the battery:
1. the power consumption of the mobile phone in standby mode is very small. That is to say, the equivalent load resistance of the battery is large, so the discharge current is very small, so the battery will not heat up, and the internal consumption of battery energy is very small.
2. When a mobile phone is waiting for a call or game, the power consumption is very high. That is to say, its battery equivalent load resistance is small, and it is a large current discharge during work. After the battery is powered off, the internal resistance increases. However, the current required for the operation of the mobile phone cannot be reduced. Therefore, a considerable amount of energy is consumed on the internal resistance of the battery, resulting in heat of the battery, discharge acceleration shortens the battery time.
These are the reasons why cell phone batteries will heat up after a long period of use.
Mobile phone battery heat hazards:
1. If the phone battery is too hot for a long time, the phone's internal device may heat up, so that the phone can be restarted or hung up.
2. the phone battery heat for a long time will increase the heat of the battery itself. If it is a sealed (NOKIA is not sealed, it is directly loaded into the battery), the battery will make its internal air expand sharply, lead to a sudden explosion of the battery.
3. Mobile phone battery will accelerate the aging process of the mobile phone itself and shorten its life.
The above is the danger of cell phone battery fever for a long time.

Cell phone battery fever prevention and solutions:
I. Preventive Methods:
1. When the phone is at normal room temperature, the heat cannot exceed 60 ℃, which is a normal phenomenon and will not damage the battery.
2. Using a large current charger should not be too long. Charging for too long will damage the battery and generate heat.
3. It is best to use the original charger or products with good quality reputation.
4. If you are not in a rush to use it, it is recommended that you use a landline charge (slow charge mode) for charging, so that the battery will not heat up.
5. When using a mobile phone to listen to MP3 or battery charging, if the phone feels a little hot, you can use * #0228 # to view its temperature, such as more than 60 ℃.
Then immediately return to the STANDBY state or use another battery. If you are charging, immediately unplug the charger.
Ii. solution:
1. If the cell phone battery has been fully occupied, you can solve the problem. Just use your finger to find the gap between the battery (the back of the cell phone battery is close to the side of the cell phone's charging electrode, and press it to a soft place, let the air in it run out.
2. Buy another battery.

We know that batteries are the source of cell phone power, that is, the power of cell phones. There is no battery power, and the cell phone is also a scrap iron, a high-capacity and high-performance battery, it not only provides long-time endurance for the mobile phone, but also protects the circuit of the mobile phone so that the mobile phone can work efficiently for a long time. Otherwise, it is likely to cause unexpected damage to the mobile phone. For our players, the battery performance is determined by the battery itself when it is released. The battery capacity and performance are determined by the battery itself, in this respect, we can't change people, but it doesn't mean that we can't do anything about it after we get the battery. The mobile phone uses a lithium-ion rechargeable battery. Once the storage power is used up, you need to recharge the battery to replenish the power. Do not underestimate the charging process. A good charger and the correct charging method can keep the battery in standby time for a long time and prolong the battery life. Further, mobile phones can also be protected. I have summarized the following points for my actual use and reference on how to charge:
1. Before the lithium battery leaves the factory, the manufacturer activates the lithium battery and performs pre-Charging. Therefore, the battery has residual power. The new cell phone battery is lithium ion, so the first 3 ~ 5 times of charging is called the adjustment period. It should be charged for more than 14 hours to ensure full activation of lithium ion activity. The lithium-ion battery has no memory effect, but it has a strong defect. It should be fully activated to ensure optimal performance in future use. With regard to the first charging problem, the original lithium battery has been fully activated before leaving the factory, and there is no need to use a long-time charging method to activate the lithium ion activity, for the first charge, you only need to fill the remaining power in the battery after use.
2. Some automated smart quick chargers only indicate 90% full when the signal lights change. The charger automatically changes and uses slow charging to fill the battery. Do not immediately cut off the power of the charger, it is best to give the battery a power-on time, the battery is fully occupied before use, otherwise it will shorten the use time.
3. before charging, the lithium battery does not need discharge or discharge. The current lithium battery charger does not have the discharge function. If you can adjust the charging speed, it is recommended that you try to charge slowly to reduce the charge mode; no matter the charge is slow or the charge is not more than 24 hours. Otherwise, the battery may burn out the battery core because of the large electronic flow generated by the power supply for a long time.
4. many users keep their mobile phones on when charging. During the charging process, the battery is discharged outward due to the use of the mobile phone, and the battery is charged internally, it is very likely that the circuit board of the mobile phone will heat up due to voltage disorder. If there is a call, it will generate an instant reflux current, causing damage to the internal parts of the mobile phone.
5. the battery life is determined by the number of repeated charge and discharge times. The lithium battery can charge and discharge about 500 times consecutively, and the performance of the battery will be greatly reduced. Try to avoid fully charging the remaining battery power, otherwise, the battery performance will gradually decrease as the number of recharges increases, and the battery's standby time will be hard to keep falling.
6. Do not expose the battery to high temperatures or cold temperatures, such as three-volt days. Do not put your cell phone in the sun to withstand the scorching sun; or take it to the air-conditioned room and place it in the air-conditioned place. When charging, the current product returns back, and the battery has a slight fever.
7. If the cell phone battery is not used for a long time, you 'd better apply to the mobile phone repair department to activate the battery,
You can also use a DC constant voltage regulator to adjust the voltage to 5 ~ 6 V, current 500 ~ 600mA reverse connect battery. Note: You can open it in one click and repeat it three times at most. After such processing, use the original charger for "adjustment period" charging.
8. The longer the charging time, the better. If the battery without protection circuit is full, the charging should be stopped. Otherwise, the performance will be affected due to fever or overheating. The method for calculating the battery charging time is as follows: the battery power can be divided by the charger's output current. For example, a battery with a battery power of MAH is used as an example, if the charger's output current is 800 Ma, the charging time is equal to 1.6 MAH/MA = hours. Of course, this is only a theoretical calculation of the charging time. When the charger shows that the charging is complete, it is best to give the battery about half an hour of power-up time. A dedicated charger must be used for the lithium-ion battery; otherwise, the charger may not be available.
The saturated state affects its performance.
Currently, there are three types of cell phone batteries: nickel-cadmium (Nicd) batteries, nickel-metal hydrogen (Nimb) batteries, and lithium-ion batteries. Nickel-cadmium battery can load large current, suitable for fast charging, the disadvantage is that the battery is easy to produce memory effect, nickel metal hydrogen battery, known as "Environmental Protection Battery" by industry insiders ". It is a cell phone battery with excellent quality, safety and reliability, and is environmentally friendly. The storage energy density of lithium-ion battery is high, which can reduce the weight of the cell phone. The disadvantage is that the cost is high.
Pay attention to the following aspects to extend the battery time of mobile phones:
1. fast charging some automated smart and fast chargers. When the indicator lights change, it means it is full of 90%. The charger automatically changes and uses slow charging to fill the battery. It is best to fill the battery and use it later, otherwise it will shorten the use time.
2. Battery memory effect. The nickel-cadmium battery is not fully charged and discharged for a long time. It is easy to leave traces in the battery to reduce the battery capacity. This phenomenon is called the battery memory effect. Specifically, the battery seems to be able to remember the daily charge, discharge range and mode of the user. It is difficult to change this mode for a long time, and it is not possible to perform heavy charge or discharge.
3. Basic charging methods. The battery features are different, so the charging should be carried out according to the method specified in the manufacturer's manual. In standby mode, the phone also consumes a battery. For fast charging, you must first turn off the phone or take out the battery before charging.
4. The memory battery should be deleted regularly because of its memory effect. The method is to completely discharge the battery,
Then refill. Discharge can be done by using the discharge appliance or charger with discharge function, or by using the standby mode of the mobile phone. If the accelerated discharge enables the display screen and the phone button lighting to ensure the battery is full, the time should be controlled according to instructions, repeat the charge, discharge two to three times.
★Using the power-saving mode GSM standard has an advanced feature, that is, most mobile phones have the "DTX" discontinuous launch power-saving mode. In order to save power, when the host does not send a message, the phone will temporarily reduce the power of the radio waves. Experiments show that the DTX power-saving mode can prolong the call time by up to 30% to 50%, in quiet scenarios, you should switch to relatively quiet, short phone ringtones, and choose to turn off the display or button lighting. Avoid too low battery temperature in severe cold cases. Otherwise, the use time will be shortened.

Note the following three points for the use of lithium-ion batteries:
1. How to charge a new battery
When using a lithium battery, it should be noted that the battery enters sleep state after being placed for a period of time, the capacity is lower than the normal value, and the use time is shortened. However, the lithium battery can be easily activated, and the battery can be activated after 3-5 normal charging and discharging cycles to restore the normal capacity. Because of its own characteristics, the lithium battery has almost no memory effect. Therefore, the new lithium battery does not require special methods and devices during the activation process. Not only in theory, but in my own practice, the "natural activation" method of charging with the standard method was the best from the very beginning.
Many sayings about the "activation" problem of lithium battery are that the charging time must be over 12 hours, and the battery must be retried three times to activate the battery. This "charge for the first three times is charged for more than 12 hours" is obviously a continuation of the statement from the nickel battery (such as nickel-cadmium and nickel-Mh. Therefore, it can be said that it was a false positive at the beginning. The charging and discharging characteristics of lithium battery and nickel battery are very different, and can be clearly told to everyone, all the serious official technical materials I have read have emphasized that charge and discharge can cause great damage to lithium batteries, especially liquid lithium-ion batteries. Therefore, it is best to charge according to the standard time and standard method, especially do not charge over 12 hours.
In addition, lithium battery or charger will automatically stop charging after the battery is full, there is no nickel charger called for a 10 hours of "Drip" charging. That is to say, if your lithium battery is fully filled, it is also a white charger. No one of us can guarantee that the battery charging and discharging protection circuit features will never change and the quality will be safe, so your battery will be on the verge of danger for a long time. This is another reason for us to oppose long charging.
In addition, if you do not remove the charger after charging for a certain period of time on some machines, the system will not only stop charging, but also start discharge-charging cycle. The vendor may have its own purpose, but it is obviously unfavorable for the battery life. At the same time, long Charging takes a long time and often needs to be carried out at night. However, in the case of China's power grid, the voltage at night is high in many places, and the voltage fluctuates greatly. As we have already said before, lithium battery is very delicate. It is much inferior to the ability of nickel power to withstand fluctuations in charge and discharge, which brings additional risks.
In addition, the lithium battery is not suitable for overdischarge, And the overdischarge is also very unfavorable to the lithium battery. This raises the following question.
2. When should I start charging normally?
Because the number of charge and discharge operations is limited, the power of the lithium battery should be used up and recharged as much as possible. However, I found an experiment table on lithium-ion battery charging and discharging cycles. The following figure shows the cycle life data:
Cycle Life (10% DOD):> 1000 times
Cycle Life (100% DOD):> 200 times
DOD is the abbreviation of discharge depth. As can be seen from the table, the number of recharges is related to the discharge depth. The cycle life of 10% DOD is much longer than that of 100% DOD. Of course, if it is equivalent to the actual total charge capacity: 10% * 1000 = 100,100% * 200 = 200, it is better to fully charge and discharge the latter. Under normal circumstances, you should keep your battery recharged Based on the remaining battery usage principle, but if your battery is not expected to survive the whole day for 2nd days, charging should be started in time. Of course, if you are willing to carry a charger to the office, you should not talk about it.
However, when you need to charge for important events that are expected to result in busy communications, even if there is still a lot of power off in the battery, you just need to charge in advance, because you have not really lost the "1" charge cycle life, that is, "0. x times, and often this x is very small.
The principle of remaining battery power usage and re-charging does not require you to go to the extreme. Like long charging, it is widely used to say that "it is best to use up the battery power of the machine as much as possible and use automatic shutdown ". This is actually just a nickel battery method, the purpose is to avoid the memory effect, unfortunately it also spread on the lithium battery. There was a warning that the battery of the machine was too low, and the machine was still not charged. Results In this example, the machine did not respond in the subsequent charging and startup, and had to send it to customer service for repair. This is because the battery voltage is too low due to excessive discharge, so that it does not have normal charging and boot conditions.
3. correct practices for lithium batteries
To sum up, the most important tips for lithium battery charging and discharging problems in use are:
1. charge according to the standard time and procedures, even the first three times;
2. When the power of the machine is too low, you should start charging as soon as possible;
3. Lithium Battery activation does not require a special method. The lithium battery will be activated automatically during normal use of the machine. If you insist on using the "first three 12 hours long charge activation" method, it will not actually work.
Therefore, all the 12-hour ultra-long charging and the use of lithium battery power-off are wrong. If you used to follow the incorrect statement, please correct it in time. It may not be too late.
4. Use lithium batteries for fire prevention
Many people may be familiar with lithium batteries from mobile phones. In fact, it is used in many household appliances. Beyond all doubt, the advantages of lithium battery efficiency and lightness are making it widely used. However, do you know that accidental use can also make you angry.
Lithium Battery has the advantages of being light, efficient, and low temperature resistant (-40 ℃). Lithium Battery of 3mm thick and stamp size can be used continuously for more than 5 years, in recent years, alkaline dry batteries and manganese batteries are gradually eliminated and are widely used in many high-end household appliances and mobile phones.
Lithium Battery is different from the existing manganese battery and Alkaline Dry Battery of zinc chloride and potassium hydroxide water-soluble electrolyte, it uses organic solvent. Lithium Battery Cathode Materials such as manganese dioxide, lead fluoride and sulfur chloride. The lithium metal foil used in the negative electrode is more likely to ionic than the zinc chloride used in the negative electrode of the general battery, and the voltage difference between the positive and negative electrodes increases the working efficiency of the lithium battery. However, the lithium battery is often heated and burned during use, and the light affects the use of the host. In severe cases, the host will be burned down, causing a fire. According to reports, many domestic fire incidents have occurred in Japan in recent years due to lithium battery burning. Why is lithium battery burning? After many materials in the lithium battery are in contact with water, intense chemical reactions can occur and a large amount of heat energy is released, resulting in heat and combustion. Lithium Battery Cathode manganese dioxide, only a small drop of water can appear fever phenomenon. After the sub-sulfur chloride in lithium battery is in contact with water, heat energy is released when hydrochloric acid and sulfur dioxide are generated. Several factors make lithium battery a "fire" in life ", therefore, people must pay attention to water and moisture when using lithium batteries. After various hosts are disabled, the lithium battery should be taken down and put in a dry and low temperature place for proper storage to prevent and avoid family problems caused by improper use of lithium battery.
The occurrence of a fire accident.