What if the old lithium batteries are not charged? ?
Three methods of lithium battery repair:
1。 Use a clean eraser or other material cleaning tool to gently wipe metal contacts on lithium batteries and mobile phones, which will contribute to the charging status and power durability。
2. The old mobile phone lithium batteries used for automatic shutdown are wrapped tightly with fresh-keeping film. When wrapped, they are as close as possible. There are three layers inside and outside to ensure that the batteries are in a vacuum state. Then, three layers of newspaper were wrapped outside the film to make the lithium battery completely sealed. After 48 hours, take out the batteries and remove the six layers of paper wrapped in the refrigerator. The lithium batteries did not expand or deform due to freezing. After cooling for a period of time, then charging.
3. Discharge lithium batteries that are close to scrap completely, then recharge and activate the batteries. Specific methods are: deep discharge of mobile phones, that is, to achieve deeper recharge by depleting internal energy, which requires some unconventional methods. Connecting a cell phone to a low-voltage small light bulb with a specific device, the power inside the battery will be transmitted to the small light bulb until all the light is emitted. "Cell phones need to use up electricity slowly at lower voltages. Normally, if the cell phone is connected below the rated voltage of 3.6 volts, it will shut down automatically. The recharged cell phone batteries can last longer after the power is discharged.
Principles of three lithium battery repair methods:
Principle of lithium battery repair method 1:
The metal surface of lithium battery used for a long time will be oxidized to a certain extent, resulting in poor contact between mobile phone battery and mobile phone, shorter use time of lithium battery, and the use of rubber Sassafras or other cleaning tools can erase rusty substances on the surface, so that the contact between battery and mobile phone is better。
Principle of Lithium Battery Repair Method 2:
Professor Ye Gaoxiang, Department of Physics, Zhejiang University, explained that the "freezing therapy" of lithium batteries: "Low temperature can change the electrolyte inside lithium batteries, and promote the chemical reaction of batteries that have just been frozen. The use of lithium batteries is actually a charging and discharging process. During this period, the negative and positive charges in the battery collide with each other. The reason why batteries are becoming less and less useful is that at normal room temperature, the internal kinetic energy of electrons is relatively large, so the batteries are in active state and leakage is relatively frequent. When lithium batteries are placed in low temperature environment, the micro-structure of lithium film and electrolyte on the surface of lithium batteries and their interface will change significantly, which will cause the interior of the batteries to be temporarily inactive and the leakage current to be reduced. So after recharging, the standby time of the mobile phone will increase.
The cycle life of lithium battery is about 600 times. If charged more times, the thermal movement of the molecule will gradually destroy the internal molecular arrangement and structure, and the storage charge efficiency will gradually decrease. "The refrigeration process can easily destroy the original internal structure of the battery. It may increase the capacity to charge in a short time, but long-term use may not be effective." Professor Ye said that once the micro-structure of lithium batteries is damaged, it is impossible to recover completely. Long-term use of this method will accelerate the loss of mobile phone batteries.
Principle of Lithium Battery Repair Method 3:
is that deep discharging of mobile phone is to achieve deeper recharge by depleting internal electric energy, which requires some unconventional methods. Find a way to connect the cell phone to a 1.5V small light bulb. The electricity inside the lithium battery will be transmitted to the small light bulb until all the light is shining. "Cell phones need to use up electricity slowly at lower voltages. Normally, if the cell phone is connected below the rated voltage of 3.6 volts, it will shut down automatically. The recharged cell phone batteries can last longer after the power is discharged.
The whole process analysis of "freezing therapy" for mobile phone lithium battery repair: Nokia BL-5C original lithium battery bought in April 2009 was used as the experimental object. The lithium-ion battery has been in use for nearly two years. Under normal conditions, the standby time of the mobile phone lasts about one day. If the number of calls is higher, the duration of electricity will be shorter. If the average call time per phone is 3 minutes and the number of calls is answered or dialed 10 times, the power consumption is at stake.
Before testing, turn off the mobile phone, and then turn on when the power is full. Thereafter, no phone calls or text messages were received or dialed. In the absence of any interference, the cell phone quietly standby, nearly three days later, no electricity at all.
Enter the experimental stage: put the fully equipped lithium batteries into the freezer of the refrigerator (in order to prevent the lithium batteries from damp, we need to wrap the cell phone tightly with a fresh-keeping film first, and try to take it as close as possible when wrapping it. There are three layers inside and outside to ensure that the lithium batteries are in a vacuum state. Then, wrap three layers of newspaper outside the film to make the cell phone battery completely sealed. After 48 hours, the lithium batteries were removed and the six layers of paper wrapped around them were removed one by one. The surface of the batteries did not expand or deform due to freezing. After cooling for a period of time, the lithium battery is loaded into the mobile phone and charged and turned on. In the same case, on the third day, the cell phone that would have shut down automatically had only one power cut off on the screen. A week later, there was still one battery left on the screen. On the ninth day, the phone gave out a reminder because of insufficient power.
The performance before and after the "freezing therapy" test confirms that the cell phone's standby time can be prolonged by the first frozen battery。 But freezing is not the "immortal panacea" of mobile phone batteries。 Long-term use can damage lithium batteries。
Experts warn that the price of lithium batteries is not too high. Instead of trying to repair them, it's better to buy a new battery for convenience and economy. In addition, it is also a shortcut to prolong the life of lithium batteries to develop good habits.