Questions and Answers on the Research of Simple Lithium Battery Charge and Discharge Protection Circuit

Question: Hello, I have studied the charging requirements of lithium batteries and the instructions for using IC chips. Your circuit is very good, because the lithium battery has a protection circuit. But I don’t know if you have noticed that some lithium batteries that have not been used for a long time or have not caused any over-discharge protection circuit. When charging, if the voltage is lower than 3v, according to the requirements, it should not exceed 3v, 25 horses wake up The charging current, voltage 3v, such as normal charging, so it can be filled with the protection circuit in the discharge of the lithium battery, what do you think? In the data I analyzed, MAX846A should be the best designed charging chip: 2. Lithium battery and Other types of batteries can also be charged; 3. There are four different charging stages; 4. There are not many peripheral components, but I still have 5-6 patches for patchseal, one of which I have a dispute with the teacher, so I You can't solder it in your spare time. A: This is a good suggestion. I will add a wake-up part to the circuit later. If there is no such function, only manual measurement is available. Simply put forward if it does not meet the requirements, or manually change the small current to charge (because the current can be adjusted). Of course, some people say that the circuit will become more and more complicated. MAX846A is really good and normal, but besides the amateur conditions are not good for welding, I don’t know the price. Is it easy to buy? In addition, this circuit does not support 3 pieces. Or more than 3 lithium batteries, right? Q: The use of lithium batteries is to protect the plates, exploding on one side, and letting the other side dead. It is much easier to charge with the protective plate. When you are full, it will stop when you take it. Answer: The question is how much is the cost of installing a protection circuit for each part of the lithium battery, how long will it take to process, some 10X10 lithium battery protection boards, 10-day lithium battery constant current, constant voltage charger, who is more likely to DIY, who Can spend the least meters, easier to DIY, discharge protection is a must, of course, otherwise after discharge from the hospital, the lithium battery will be reimbursed. Question: This is not a daily protection board, it is a whole, the discharge voltage, in fact, one of the most commonly used parts, the second part and the three questions, in parallel, the relationship between the 1-3 protection boards is mature and cheap, 18 Two feet of dual field effect tube, only one 5 teaching control IC, 2, 3, resistance, only add fuse. Answer: Another lithium battery charge termination voltage, 4.2V, 4.1V or other, does not make much sense, because the consistency of the lithium battery is not good, so the series cannot be charged, so the termination voltage of the lithium battery is not exactly the same, so I think that the termination voltage is lower than 5% to 4.2V, and the battery is fully charged to 100%. It is not a reality, and it is not necessary in practical applications. This leads to the complexity of the charging circuit. This wisdom is the established design. The cumulative error of the components will cause This leads to greater errors, which is not advisable for DIY. If the circuit in Figure 1 can accurately control the maximum voltage of a lithium battery with a demarcation point of less than 5%, the protection circuit can be ignored, and the termination voltage setting at 4.00 should be very safe. . A: Test the voltage of each battery separately when charging in series. As long as a battery is fully charged, it will be powered off. This method is sufficient. If it is all full, it will be discharged to N to escape the charging and discharging path, and the charging and discharging circuit works under high current, and the power problem is much more difficult than the detection circuit. For example, a 4.2v voltage regulator tube is connected in parallel with each battery, which is only suitable for small current charging. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous article: Explanation of the meaning and scope of use of Ni-MH rechargeable batteries