The charger manufacturer takes you to know the -△V stop mechanism of the smart Ni-MH battery charger

First of all, explain the judgment method of -△V, because the full charge of Ni-MH battery is relatively full, not absolute, so the judgment of Ni-MH battery charging has always been very complicated. There are three ways to stop charging designed by Ni-MH battery chargers on the market: 1. Time control (time off) 2. Constant voltage (charge to a set voltage) 3. -△V (intelligent algorithm, negative pressure judgment) Stop, why it is called negative pressure will be explained below) The above 3 best ways is -△V, this algorithm is to detect a voltage drop phenomenon caused by the Ni-MH battery during the charging process through the IC control chip. Hereinafter referred to as (negative pressure), the following figure is usually used as the standard -△V diagram (the blue line is the real-time battery voltage) (Note: This figure was derived from the early days when only Japan mastered this technology, due to the battery technology and The charger is not advanced yet, so it needs a regular and continuous negative pressure monitoring and a continuous charging process, which finally produces a significant drop in the voltage curve trend in the figure) However, the actual situation-the negative pressure phenomenon of △v This is not the case. There is a negative pressure phenomenon during the entire charging process of the Ni-MH battery. When the battery has a small amount of power, the value of the negative pressure is relatively large. After the Ni-MH battery is continuously charged, the negative pressure will increase as the amount of power increases. The value will get smaller and smaller. According to this feature, when designing a Ni-MH battery charger, we only need to set the charger to only capture negative pressure data within a certain range as the basis for the charger to stop charging, so that safe charging can be achieved. The controversial charger of RYD225 judges to stop charging according to this algorithm. Strictly speaking, RYD225 is a very accurate charger for charging and stopping. It stops charging very thoroughly. It omits the continuous charging process after detecting the negative pressure signal and avoids the problem of high temperature of the Ni-MH battery at the charging end. (High temperature is a big killer of Ni-MH battery life). However, the detection curve will lead to doubts from some more professional players who have certain knowledge but do not have more professional equipment to do the detection. The figure below is a screenshot of a report that our equipment detects the judgment of the Ni-MH battery charger. This is the graph. The following is the detailed data of the voltage when the charger is stopped. Please pay attention to the above figure. The above figure has a total of 6 data. When the charger stops charging, the continuously detected variable is that when 0.001V appears 2 to 3 times, the charger stops charging. And this kind of millivolt level data, no curve can be drawn out. If there are still doubts, it is recommended that the other party call detailed data for comparison. However, Ni-MH battery chargers with this accuracy are rare in the market. The chargers produced by our company have very high accuracy. There is no doubt whether there is a mechanism for stopping the charge of -△V, and it supports the detection of any institution. 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: How to correctly understand the safety test and abuse test standards of power batteries?