Why is a lithium battery made up of three wires? What is the function of each wire?

Two possibilities! 1) If your battery does not have a protective board, the three wires are: the red wire is the positive pole, the black wire is the negative pole, and the other color wires are the battery middle pole. These three wires are connected to the motherboard of your product. The middle pole is to give you the product motherboard to monitor the voltage of the lithium battery.

　　2) If your battery has a protective plate, the three wires are: the red wire is the positive battery, the black wire is the battery negative, the other color is the NTC (thermistor) of the protection board, and the thermistor is the lithium battery for the motherboard. The temperature is either the type of battery. Of course, these are the most clear to you. Asking others is to answer a lot of things, because your question makes people have a lot of guesses. Of course, in addition to these two, it may be a lot better. For example, there is a line that is the balanced charging line of the battery, the data signal line, etc. If you know exactly the operation of the three lines, please tell me where the three lines are connected?

　　With the decline in the price of lithium batteries, many areas in the market have begun to use lithium batteries to replace the original lead-acid batteries, nickel-metal hydride batteries, etc. Due to the activity of lithium ions, the use of lithium batteries must be protected with protective plates to prevent lithium The battery is overcharged and discharged.

　　Schematic diagram of wiring

　　1. Protection board connection battery wiring sequence: ☆ Special attention: The wiring of different manufacturers is not common. Please make sure to use the matching cable: 1 Ensure that the cable is not inserted into the protection board before connecting the cable; 2 Protect the board B-line (blue The thick color line is soldered to the total negative pole of the battery; the 3rd line starts from the thin black line connecting B-, the second line (thin red line) is connected to the positive pole of the first string of batteries, and the positive pole of each string of batteries is connected in turn, until the last one String B+; After the 4th cable is connected, do not insert the plug directly into the protection board, measure the voltage between each two adjacent metal terminals on the back of the plug. If the voltage of the ternary polymer battery should be between 2.8~4.2V, the iron-lithium battery It should be between 2.5~3.65V, lithium titanate battery should be between 1.6~2.8V; after the 5-wire wiring sequence and voltage are confirmed, insert the protection board socket again.

　　After the wiring is completed, measure the battery B+, B-voltage and P+, whether the P-voltage is equal, and the protection board works normally, and it can be used normally. If they are not equal, please check again according to the above wiring sequence. PS: The method of connecting the same line and the split port is the same. The difference is that the method of discharging (load, motor) and charging is different. The negative poles of the same port charge and discharge are connected to the P- line; the split port is connected to the C-line and the discharge is connected to the P- line.

　　1. Press the B-line terminal and the multi-meter red test lead B1 line terminal with the black pen of the multi-meter to obtain the first series battery voltage is 3.584V.

　　2. By pressing the B1 line terminal with the multi-meter black test pen and the red table pen pressure letter B2 line terminal of the multi-meter, the second series battery voltage is 3.584V.

　　3. Measuring by this method, it is concluded that:

　　The first string battery voltage: 3.584V

　　The second string battery voltage: 3.584V

　　The third string battery voltage: 3.585V

　　The fourth string battery voltage: 3.585V

　　The fifth string battery voltage: 3.583V

　　The sixth string battery voltage: 3.583V

　　The seventh string battery voltage: 3.584V

　　The 7-string voltage is 3.58V, the wiring is correct, and the battery voltage difference is less than 0.002V, and the battery consistency is good.

　　By connecting the B-line, measure the voltage of B- and the total positive pole of the battery and the voltage of P- and the total positive pole of the battery.

　　The voltage is the same, indicating that the protection board is normal (the protection board is equivalent to the switch, the switch is already open, and the current can pass safely)

　　Example test:

　　B-to the battery total positive voltage is 25.11V

　　P-to the battery total positive voltage is 25.11V

　　The two voltages are consistent to indicate that the protection board is normal. If P- discharges through a large current, there will be a slight pressure drop, and the protection plate will heat up (about 50 degrees), which is a normal phenomenon.

　　The connection cable must be correct. If the wrong line is connected, the protection board will be burned out. Therefore, the voltage of each string is confirmed by the voltage to ensure that the line is not connected incorrectly.

　　If it is an old battery, the voltage difference between each string of the battery is greater than 0.1V. The battery string with large difference is likely to have virtual power, and the capacity and resistance change, which will form a short board effect of the barrel, resulting in overcharge and overcharge protection. The discharge is too fast and overcharge protection, and the simple understanding is that the battery life is short, and the application time of the electric vehicle and the like is short.

　　The protection board protects each string of batteries, and any string of overcharge or over discharge will cause protection. If it is a 4s lithium battery, it is 0, 3.7, 7.4, 11.1, 14.8, and 5 different potentials. If it is a protected version, the two red and black ones should be internally shorted, and the two are to increase the current. White is the flag of the protection chip. It is a high battery after protection and a low level when it is not protected. Lithium battery has 5 wires, two red, two black, one white, what is the definition of each type?

　　Three-phase voltage instability will cause heat or even burn out the motor, because the three-phase motor is a three-phase balanced load, that is, the impedance of each phase load is equal. When the power supply is a symmetrical three-phase voltage, the current flowing through each phase load is equal, but the power supply When it is an asymmetric three-phase voltage, the current flowing through each phase load is not equal, and the current in one phase load will become high (may far exceed the rated value), so the phenomenon you mentioned.

　　The two-wire DC motor is internally connected (such as a shunt motor) or only two wires (such as a toy); one of the three DC motors is a common line, and the other two are armatures. And excitation lines (such as series excitation motors for electric tricycles).

　    First, the NiMH battery charger is pulsed! The voltage is around 1.5V! But the 18650 lithium battery should be charged with 4.2V constant current and constant voltage! You can use the mobile phone charger to change!

    Yes, there is a goose for testing. Q: Does the system firmware not think that the battery is out of order? Answer again: If it is the Tianchao, there is no problem, pay attention to the positive and negative poles. There may be chip detection in foreign countries.