In the development and testing of electronic products, charge and discharge test is a very common test item. A complete charge and discharge test usually includes the following 3 steps:
1. Drain the battery
2. Fully charge the battery and record the complete charging curve
3. Drain the battery again and record the complete discharge curve
In general, especially when the battery capacity is large, the discharge or charge of the battery is time-consuming, especially the discharge (which requires two cycles). For discharge, for convenience, most engineers do this:
Directly connect a cement resistor to the battery (such as a 3 ohm cement resistor, you can get more than 1A discharge current), and then throw it into the corner, and do other things. When you remember it, see if the battery is empty.
This practice, for batteries with lithium protection, is OK, after the battery is discharged to the lithium protection voltage, the lithium protection will turn off the output of the battery and protect the battery. But for batteries without lithium protection, it is very dangerous! It will cause battery overdischarge damage! So pay special attention!
In order to avoid battery overdischarge and damage, you can use a special discharge test board (with lithium protection on it), which can be referred to the next article.
Original article, Please mark the attribution when reprinting. SINHMICRO, www.sinhmicro.com.