Lithium battery square lithium ion

Square lithium-ion batteries are the most common lithium batteries in life. There are many models of them. They are widely used in MP3, MP4, mobile phones, model airplanes and other products.
Square lithium-ion batteries are divided into two types: metal shell packaging (silver-white hard shell) and aluminum-plastic shell packaging (gray-white soft shell, which can be scratched with fingernails). Metal shell packaging is lithium-ion battery or liquid lithium battery, and aluminum-plastic shell packaging is lithium-ion polymer (polymer) battery (Lithium ion polymer battery). The chemical materials and electrochemical properties used in these two batteries can be said to be similar. The main difference is that lithium-ion polymer batteries use some colloidal substances to help the battery plates fit or absorb electrolytes, reducing the amount of liquid electrolytes used, so that the battery packaging can be changed from metal shell to aluminum-plastic shell.
The outer shell of the metal shell lithium battery is the negative electrode, and the positive electrode is on the protrusion on one side of the battery; the positive and negative electrodes of the aluminum-plastic shell lithium battery are two plates on one side of the battery, and the outer shell is an insulator.
For square lithium-ion batteries, the model number is generally 6 digits. As shown in the following table. The first two digits are the thickness of the battery with 1 decimal place; the middle two digits are the width of the battery; the last two digits are the length of the battery. The unit is millimeter. For example, the 606168 lithium battery has a thickness of 6.0 mm, a width of 61 mm, and a length of 68 mm. (Note: Due to the different packaging methods used by various battery manufacturers, the capacity of square lithium-ion batteries of the same model varies within 300mAh)
The nominal voltage of square lithium-ion batteries is generally 3.6~3.7V, and the charge termination voltage is generally 4.2V.