MAZDA6 I-Stop not working and I-ELOOP not charging

The problem is the I-eloop sometime not charging when I drive my car, it will cause iStop also not working and light goes off on the dash board, the Eloop charge value is at only one bar on the dashboard(not increase)，at the same time，I can hear some noise when I let go of the accelerator . This problem happened lots of times and after a while(a hour or a day), it will normal again. I don't know if it is I-eloop problem or it is battery problem, does anyone has same problem and solve it?

Видео MAZDA6 I-Stop not working and I-ELOOP not charging канала Ming Hua