With the development of science and technology, now lithium battery products have become the mainstream. Lithium batteries are a type of batteries made with lithium metal or lithium alloy as the negative electrode material and using non-aqueous electrolyte solutions. They can be roughly divided into two categories: lithium metal batteries and lithium ion batteries. In literature and real life, lithium batteries and lithium ion batteries are a pair of concepts that are different from each other but have inheritance and development relations. As the use of lithium ion batteries becomes more and more widespread, people generally call lithium ion batteries lithium battery.
Lithium metal batteries were first developed and studied in 1912. They can also be called primary lithium batteries. They are a kind of disposable batteries, mainly lithium manganese, lithium iron batteries and so on. Lithium metal batteries can be discharged continuously or intermittently, and can no longer be used once the power is exhausted.
Lithium-ion battery refers to a secondary battery system in which two different, reversible, intercalating and de-intercalating lithium ions are used as the positive and negative electrodes of the battery. The lithium ion battery can be recharged. The similarities between lithium batteries and lithium ion batteries are the positive electrode and electrolyte. Both batteries use metal oxides and sulfides as the positive electrodes, and organic solvents or inorganic salt systems as electrolytes.
The correct charging method of lithium battery
1. Charge a new battery
A new battery generally needs to be activated. After the battery is left for a period of time, it will enter a dormant state. At this time, the capacity is lower than the normal value and the use time is also shortened, so activation is required. Lithium battery activation method is very simple, as long as 3-5 normal charge and discharge cycles can activate the battery and restore normal capacity.
2. Charging the old battery
1. Charging method
An old battery refers to a battery that has been charged and discharged many times, not a scrapped battery. The life of a lithium battery has nothing to do with the number of charging and discharging. It has no memory effect. No matter how you charge it, it will not affect the number of charging cycles. Therefore, do not charge the battery until it is completely empty. It is best to charge the battery as much as possible when you can charge it. The charging time should be within 2-3 hours. Of course, you don’t have to be fully charged.
2. Charging voltage
The safe working voltage range of lithium battery is 2.8 to 4.2V. Below or higher than this voltage range, the lithium ions in the battery become unstable. In order to ensure that the battery is in a safe range, a special charger is required. These chargers automatically adjust the charging method according to the current state of the battery.
3. Charging tools
Lithium batteries should be charged with a special charger, which can guarantee the safety of charging. When the charger works, it charges the battery with a constant current. As the battery voltage increases, the charger increases the charging voltage at the same time to speed up the charging speed. When the battery reaches the 4.2V cut-off voltage, the battery only charges about 70% (not full) at this time. At this time, the charger continues to charge the battery with a constant voltage and a gradually decreasing current. When the value is less than 0.1A, the charging still detects that the battery voltage continues to rise.
4. Regularly charge
Lithium batteries that have not been used for a long time should be stored in a cool and dry place in a half-charged state. Storing the battery at full charge will cause damage, while storing without electricity, the battery may be damaged and lose its function. In the storage process, every 3–6 months, a charging cycle must be completed and a power calibration will be done.