Yes, your picture is showing the correct bolt covers. I just took a razor knife and kind of put the blade into the plastic on the caps (to get grip) then popped them out. I think the screw heads underneath are a 2 MM Torx head. The "rubber band" type thing around the battery housing should come off when you separate the two halves of the housing.

When I took my battery pack apart I thought it was heat sealed together. So, I took off the "rubber band" then took a hacksaw and cut the screws at the corners of the housing. "hack" is an operative word here! That's when I was able to see how the screws and caps were employed in the design. You should be able to separate the two halves as I have previously described.
Good Luck!