Review on 3.7V 18650 Lithium Battery Cell PCB BMS Protection Board with 5S 50A Balance by Maurice Jimenez

I use it on a 4S21P Li-Ion block of 18650 cells with a capacity of about 50Ah. The under voltage worked fine, there was no output as expected. As many have said, Overcurrent also works as advertised. However, I doubt the ability to balance the cells. I stopped charging when one of the cells reached 4.205 volts and let it sit. The delta was 130 mV between the highest and lowest cell. After 2 days of inactivity I expected the highest cell to be closer to the lowest cell as the balancing function should start draining the higher cells. Today the highest cell compared to the lowest cell is 145mV, which I don't want to see. I understand that the equalization will take a long time due to the low equalization current, but this is going nowhere.