With the development of microelectronic technology in the 20th century, the number of miniaturized devices has increased day by day, placing high demands on power supplies. Lithium batteries then entered a stage of large-scale practical use, especially in mobile phone battery applications. The commonly used specification for mobile phone lithium-ion batteries is: lithium-ion secondary batteries. The nominal voltage of commonly used cell phone lithium-ion batteries is 3.7 V (or 3.6 V), and the charging cut-off voltage is 4.2 V (or 4.1 V, depending on the brand of battery cells).
The charging requirements for lithium-ion batteries (GB/T18287 2000 specification) are first constant current charging, that is, the current is constant and the voltage battery capacity gradually increases with the process ofe load. The terminal voltage reaches 4.2V (4.1V), change the constant current load to constant voltage load, that is, the voltage is constant and the current gradually decreases as the process Charging continues depending on the saturation level of the battery core. at 0.01C, charging is considered complete. Please note that C is a way of expressing the battery's rated capacity versus current. For example, the battery has a capacity of 1000 mAh, and 1C is the charging current of 1000 mA. Note that this is mA, not mAh. 0.01C corresponds to 10mA. Of course, the standard representation is 0.01C5A. So why do you think 0.01C marks the end of charging? In fact, this is stipulated in the national standard GB/T18287-2000. In the past, everyone generally used 20 mA as a starting point. The industrial standard YD/T998-1999 of the Ministry of Posts and Telecommunications also stipulated this.nt, that is, regardless of the battery capacity, the shutdown current is 20 mA. The 0.01C specified by the national standard allows charging more fully, which is beneficial to the manufacturer during evaluation. In addition, the national standard stipulates that the charging time should not exceed 8 hours, which means that even if it has not reached 0.01C, after 8 hours, the charging is considered complete. Since good quality batteries should reach 0.01C in 8 hours, there is no point waiting for poor quality batteries. Therefore, I would like to remind everyone that charging should not exceed 8 hours, which is beneficial for battery life. Most mobile phones today use lithium batteries or lithium polymer batteries, which are batteries made of lithium metal or lithium alloy as negative electrode materials and using solutionsnon-aqueous electrolytes. The first lithium battery to appear came from the great inventor Edison. Since the chemical properties of lithium metal are very active, the processing, retention and use of lithium metal are subject to very high environmental requirements. Therefore, lithium batteries have not been used for a long time.
Can cell phone lithium batteries be charged at any time?
When a lithium-ion battery is charged, the direction of movement of the lithium ions is: lithium ions move from the positive electrode to the negative electrode.
When the battery power is connected and the lithium-ion battery is charged, the positive electrode loses electrons and the lithium ions escape from the crystal lattice of the positive electrode material , enter the electrolytic cell and pass through the separator and move towards the elementnegative electrode, and at the same time reach the negative electrode. The lithium ions on the negative electrode are embedded in the negative electrode material, and the electrons also reach the negative electrode through the external circuit. of the negative electrode combine with the embedded lithium ions to form a lithium-carbon interlayer compound.
When the battery is discharging, the reverse process occurs. It can be seen that during the charging and discharging process, the movement directions of lithium ions and electrons are consistent. The difference is that lithium ions move back and forth in the circuit, while electrons are transmitted. the external circuit.
Working principle:
Lithium metal batteries generally use manganese dioxide as the positive electrode material, lithium metal or its metal alloy as negative electrode materialtive, and use a non-aqueous battery with an electrolyte solution.
Discharge reaction: Li+MnO2=LiMnO2
Lithium-ion battery:
Lithium-ion batteries generally use metal oxide alloy lithium as cathode material and graphite. as cathode material. Negative electrode materials, batteries using non-aqueous electrolytes.
Reference for the above content: Baidu Encyclopedia - Lithium Battery
Lithium batteries do not have a memory effect and can be charged at any time to reduce. the number of charges, the battery is deliberately depleted. Recharging the battery will not extend battery life, but will have a negative impact on battery life. In fact, when charging lithium batteries, it is important to "eat less and eat more". Frequent superficial charges and discharges will help prolong their life.e of life.
You can charge your phone at any time. You don't need to wait for the low battery alarm or for the phone to be completely discharged. Additionally, when you charge your mobile phone, you should keep the phone in sleep state with black screen and try not to watch videos or play games. When you need to use your mobile phone to talk, it is best to unplug the charging plug. otherwise it will also affect battery life.
Detailed information:
The charging and discharging of lithium batteries mainly depends on the movement of lithium. ions. The working principle of a lithium-ion battery is that the electrolyte inside the battery reacts chemically, causing a potential difference between the positive and negative electrodes to generate current.
In environments with lowsse temperature, the electrolyte moves slowly, which affects the activity transfer of lithium ions between the positive and negative electrodes, leading to a decline in the charging and discharging performance of the battery in high temperature environments; the internal pressure of the battery increases. When the pressure reaches a certain level, the battery may explode. Analytical data indicates that ordinary lithium batteries should be used in an environment with a temperature between 0°C and 35°C.
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