The correct use of lithium batteries

Many people are afraid of lithium batteries, but also helpless. Helpless because cell phones, laptops, tablets and other equipment should use it, fear because I do not know what day lithium batteries will suddenly be in front of their own terrorist attacks: or burning, or explosion. Of these events, the nature and the lithium battery itself, the electrical properties, but also does not rule out whether the proper use of lithium batteries, lithium batteries are also caused by one of the reasons for the accident.

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Lithium battery accidentally used lithium battery

The method is based on the characteristics of the lithium battery itself. Therefore, we first analyze why the lithium battery explodes or burns electrically. Burning or explosion, usually because of heat accumulation and not spread out, accumulated to the ignition point, or heat in a certain space to a certain extent, will occur. As a battery, to sum up, the above situation does not usually occur for the following four reasons.

1, the internal short circuit (mostly flexible package of large monomer): structure or process defects lead to ear interpolation, less excess membrane package, burrs, membrane discounts. Polar insert often appear in the thick battery and the parallel structure, the ear location insulation is not in place, in the subsequent product plus protective plate or the use of the process easily lead to internal short circuit and thus the occurrence of combustion or explosion (internal short: There is a deep understanding, was also scrapped more than 2K of the battery, is actually a design flaw - abnormal nature is: internal acute short circuit), but now this situation is very small, unless external factors.

2, the external short circuit: 1AH below the battery short circuit caused after the explosion is rare, usually bulging or simply blown ears, personal analysis is a large battery or mobile phone battery short circuit caused by burning . This involves the use of improper customers - metal box does not consider the pole when the insulation in the installation site appears smoke and smoke combustion abnormalities; power batteries are also common structural fixed measures lack of consideration (not considered), the battery pack in the user process Slipping can cause damage to the battery's external insulation film or breakage of the connection sheath, eventually resulting in a short-circuit burn.

3, overcharge Explosion: This is the most dangerous, but also the most afraid of enterprises, but, or occasionally appear. From the understanding of the situation there are two points: a, the user does not require the use of matching charger, thus undermining the protection of the circuit and the user often charge are unlimited charge, this is not a bombing is difficult; b, battery pack Unreasonable and the protection board failure, this situation will be fried mess ... Similarly, a single battery.

4, the battery itself, but the material off. Material does not pass, may over-heat at a nominal voltage and current, causing an accident.

Based on the above analysis, if the correct use of lithium batteries, as far as possible to avoid the above situation, we can sort out some ways:

1, frequent depth charge and discharge: lithium battery almost no memory, many friends in the use of lithium car or lithium digital products, like to use a little power left (protection board protection) and then to recharge, and in the eyes of many people , This is also a way to activate the battery. In the use of lithium batteries, we use up the battery charge is called deep charge and discharge.

In fact, the depth of charge and discharge is a lot of people use lithium battery when a major misunderstanding, scientists concluded by experiment, the depth of charge and discharge times in other circumstances and the constant battery life is proportional to the number of charge and discharge Will lead to premature end of battery life. The end of the long service life of the lithium battery is extremely easy to cause such as battery bulging, causing an explosion.

2, over charge and discharge as well as large charge and discharge: This situation is often in the protection of the board design is not reasonable and charging occurs, we often like to recharge the device after a while full charge, so that their equipment can Anti-time longer, but many people do not know is that long-term overcharge and over discharge will have serious lithium battery performance damage and destruction, will lead to serious explosion and other extreme conditions, so the battery is fully charged Just like, if you always plug in the charger, sooner or later will lead to tragedy.

3, the charge and discharge time but also the charger current and current consumption of the general load within the specified range, the high current load can easily cause the battery's internal short circuit, thus damaging the lithium-ion, lead to circuit security risks. Similarly, the charging charger voltage, the truth is the same. So when we use the charger should also pay attention to see if the charger in the end is qualified.

4, working environment. Lithium batteries are extremely temperature sensitive, and if they are used below freezing for a long time, they can have a significant impact on battery life. Long-term exposure to overheating can drastically reduce the life of the battery. In severe cases, an explosion is caused by the increase of internal pressure. Even without explosion, the battery will be rapidly scrapped in high heat. In some cases, it is unfortunate that the battery explodes Much of the cause of death is caused by the high temperatures in their working environment.

After experiencing many accidents, the manufacturers finally took action. As most manufacturers have added protection devices, especially electronic digital products, they have added double protection or multiple protection to avoid this situation as much as possible. However, It is still important for users to strengthen their own awareness.

Lithium battery for the correct use of the phone lithium battery

Although lithium batteries are widely used in cars, electric cars, cell phones, tablets, laptops and other devices are used in the near future, there may be more equipment to use it, but for now, cell phones and tablets and the like The device is still the closest lithium battery powered device to us. Therefore, it is necessary to make special instructions for mobile phone lithium battery.

1 How to charge

In the use of lithium batteries should be noted that the battery is placed in a dormant state after a period of time, when the capacity is lower than normal, the use of time also will be shortened. But lithium battery is very easy to activate, as long as 3-5 times normal charge and discharge cycles can activate the battery, restore normal capacity. Due to the characteristics of the lithium battery itself, it has almost no memory effect. Therefore, the user's cell phone in the new lithium battery activation process, does not require special methods and equipment. Not only is it theoretically true, from my own point of view, it is best to charge this "natural activation" method from the very beginning with standard methods. For the "activation" of lithium batteries, many say: the charging time must be more than 12 hours, repeated three times in order to activate the battery. This "the first three charges to charge more than 12 hours," saying, obviously from the nickel batteries (such as nickel-cadmium and nickel metal hydride) to continue. Therefore, this argument can be said that the beginning is a misrepresentation. Charge and discharge characteristics of lithium batteries and nickel batteries are very different, and can tell you very clearly, I have reviewed all the serious formal technical information have stressed that overcharge and overdischarge will be on the lithium battery, especially the liquid lithium Ion batteries cause huge damage. Therefore, the best charge according to standard time and standard method of charging, especially not for more than 12 hours of long charging. In general, the charging method described on the phone's manual is a standard charging method suitable for the phone.

In addition, the lithium battery cell phone or charger will automatically stop charging when the battery is full, and there is no "trickle charge" that nickel-based chargers call for 10 hours. In other words, if your lithium battery is full, on the charger is white fill. And none of us can not guarantee that the battery's charge-discharge protection circuit will never change its characteristics and foolproof quality, so your battery will be hovering for a long time at the edge of danger. This is another reason why we oppose long charging. In addition, on some mobile phones, charging more than a certain period of time, if you do not remove the charger, then the system not only does not stop charging, will start the discharge - charging cycle. Perhaps the manufacturer of this approach has its own purpose, but apparently unfavorable for the life of batteries and cell phones / chargers. At the same time, long charging takes a long time, and often needs to be carried out at night. According to the situation of China's power grid, the voltage in many places is relatively high at night and fluctuates greatly. As I have already said, lithium batteries are very delicate. They are far less capable of fluctuating than nickel batteries in terms of charge and discharge, which adds additional dangers. In addition, another aspect that can not be ignored is that lithium batteries are also not suitable for overdischarge. Overdischarging is also disadvantageous for lithium batteries. This leads to the following question.

2 normal use should start charging

In our forum, you can often see this, because the number of charging and discharging is limited, so the battery should be used as much as possible to recharge the battery light. But I found an experimental table on the charge-discharge cycle of lithium-ion batteries. The data on the cycle life are listed below:

Cycle life (10% DOD):> 1000 times

Cycle life (100% DOD):> 200 times

DOD is the depth of discharge in English abbreviation. It can be seen from the table that the number of recharging times 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 the equivalent of the actual charging the relative total capacity: 10% * 1000 = 100,100% * 200 = 200, the latter fully charged and discharged or better, but in front of the user that to do something to amend that: In the case, you should reserve the battery in accordance with the principle of running out of charge and then run out of charge, but if your battery is expected in the first two days you can not insist on the whole day, it should promptly start charging, of course, if you want to back With the charger to the office is another matter. And when you need to charge to anticipate upcoming upcoming events that can lead to heavy traffic, just charge the battery prematurely, as you have not really lost the "1" charge cycle life , That is, "0.x" times only, and often the x will be small. The principle of running out of battery charge and running out does not mean you are going to the extreme. The same as the long charge, a widely circulated statement is "try to run out of battery power, it is best to use automatic shutdown." This practice is actually only the practice of nickel batteries, the purpose is to avoid the memory effect, unfortunately, it is also circulating on the lithium battery today. Someone who has not charged to continue using the example of the automatic shutdown has been used since the phone battery is low warning appears. As a result, the phone in this example did not respond to subsequent charging and power-on, and had to send customer service for repair. This is actually due to over-discharge of the battery voltage is too low, so do not have the normal conditions of charging and turning on caused.

3 Important tips for proper use of lithium batteries

To sum up, my most important tips for charging and discharging lithium-ion mobile phones in use are:

1, in accordance with the standard time and program charging, even if the first three times have to be so;

2, when the phone is too low tips, it should try to start charging in time;

3, the activation of lithium batteries do not need special methods, the normal use of lithium batteries will be activated naturally. If you insisted on using the popular "first three 12-hour long charge activation" method, in fact, will not be effective. Therefore, all the pursuit of 12 hours long charge and the lithium battery phone to automatically shut down the practice is wrong. If you have done so in the wrong words, you may correct it in time, perhaps not too late. Of course, in the mobile phone and the charger itself to protect and control the circuit quality is good, the protection of the lithium battery is still quite guaranteed. So the understanding of charging rules is the point, in some cases it is possible to make some concessions. For example, if you find that the phone must be recharged before you go to bed at night, you can also start charging before going to bed. The crux of the matter is that you should know what the right thing is and do not do it in the wrong way.

The proper use of lithium batteries battery maintenance

In fact, the battery is not too much to take into account the use of attention, in other words, take into account nor too much use. How many times a battery can be used, and more from the individual differences in the manufacture of the battery itself, rather than how to use it. In addition to its own battery quality, the battery's own life is limited. Once the battery down the production line, its life began to flow. Regardless of whether you use lithium battery life of only two to three years. One of the important reasons for the decrease in battery capacity is that the internal resistance caused by the oxidation is increased. Finally, the cell resistance reaches a certain point. Although the battery is fully charged at this time, the battery can not discharge the stored power. Many of my friends think that the initial use of lithium batteries should be charged more than 16 hours, so that you can fully activate the battery, in fact, there is no basis for doing so, this is only the popular nickel-metal hydride or nickel-cadmium battery charging method for lithium-ion batteries Not applicable. Because of this lithium polymer as the core of the battery in theory there is no memory effect, if any, is completely negligible. So only need to punch about 3 hours is completely OK, if the display charge has been completed, and temporarily do not need external power supply, then you can unplug the power, do not have to wait for such a long time.

In fact, the maintenance of the battery has been a hot topic for laptop users, and in the major notebook forum battery forum, this topic has long been a consensus. But in fact there are many misunderstandings, in the final analysis comes from two aspects, one is "thinking did not keep up with the nickel-metal hydride batteries to lithium battery change", the other is more funny, is from the phone, because the phone is actually most users The first contact with the use of rechargeable battery equipment, so it will of course put some of the habits of the phone extended to the PSP. I do not have the ability to train most PSP users as an expert, and it is not necessary. There is no absolute truth in the world. I will not vow like some of my paramount friends to vow to say that my theory must be correct, and that everyone should be convinced of him. I just will be in major notebook forums and the electrical industry Senior engineers generally agree with the point of view to share with you. After all, PSP is a consumable, no matter how hard you try, the battery life of only 2 to 3 years. If you think that in order to PSP batteries with little to almost no effect on the so-called maintenance methods, willing to get together fully charge and discharge time and often interrupt the game, waiting for the charge, then you do not have to continue to look down.

Now I will clarify some of the most easily missed misunderstandings, and given what I think the correct views and practices.

Misunderstanding one: PSP bought back and forth need to charge and discharge three times in order to activate the battery. Unless you buy the PSP is more than a year of inventory of products, or do not need to do so, because the battery cells at the time of the factory has been activated, and the batteries in the PSP battery when encapsulated again after an equivalent Activation of the test, so you get the hand of the battery, has been activated before, and then do the charging and discharging process three times just unnecessary increase in battery loss.

Myth # 2: The first charge must be sufficient for 12 hours. This is true for early NiMH devices that do not have a battery control circuit, but it is a joke for PSPs that now have an intelligent charge and discharge control module that automatically shuts off when the PSP battery is full The system displays as "external power