How to judge the positive and negative electrodes of the battery?

1. According to the design characteristics of storage battery electrode, judge the commonly used storage battery in processing design. The thicker end of the battery post is the positive electrode. The other end is thinner for the negative electrode, and the color of the battery post can be recognized. The positive electrode post is dark brown and the negative electrode is dark gray. In addition, the positive and negative marks of some batteries are represented by English letters, that is, P represents the positive electrode, and N represents the negative electrode. This must not be mistaken during maintenance and charging. 2. Using the multimeter to measure the voltage level, the multimeter can be set to the DC level, and the two meter pens are connected across the two electrodes of the battery. At this time, if the battery shows a normal voltage value, it proves that the electrode touched by the red meter pen is the positive electrode of the battery. The black test lead is the negative electrode. Sometimes it is measured that the battery does not have a normal voltage, you can measure the weak storage capacity of the battery to judge. When the two meter pens touch the battery electrodes, if the meter needles move slightly to the right, it proves that the red pen is the positive electrode of the battery. The black test lead is the negative electrode. But if the pointer of the multimeter moves to the left (the needle hits back), it proves that the negative electrode of the battery is touched by the red pen. 3. Use short-circuit wires for identification. Connect two copper core power cords to the electrodes of the old battery to be measured, and then pour the normally configured electrolyte (concentrated brine) into a glass tea cup, and connect the two power cords. Insert the ends into the teacup, and put them on both sides of the glass (the two wires cannot touch each other in the cup), and then observe the bubbling situation of the respective lead ends in the electrolyte. If the air bubbles on the end of a certain wire When the vesicles are obvious and more. It means that the end of the power cord that is connected to the battery is the negative electrode, and the end with less air bubbles is the positive electrode of the battery. 4. Use the rectifier diode to measure the unidirectional conductivity of the rectifier diode in the power supply regulator. You can find a rectifier diode. A 40w incandescent lamp. Then follow the sequence of a pile of the battery → diode + end → diode-end → incandescent lamp → another pile of the battery to form a series circuit of electric lamps. At this time, if the incandescent lamp in the circuit is ignited and emits light, it is proved The connection between the diode pole and the battery post is the positive electrode of the battery, and the other end is the negative electrode of the battery. Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous article: What are the methods to achieve balanced charging of lithium batteries?