Yes, it's been speculation that some sort of battery balancing was going on in the '13+ Leafs (which are the first to have this bouncing behavior). Both my current and previous '13 looked just like that when going 100% (most of my charging is on Chargepoint EVSEs at work).
GerryAZ wrote:The newer Leafs keep trying to get more charge into the battery by ramping up the charge rate after it tapers due to reaching maximum cell voltage. As you can see from the charge profile, they will do this several times. My 2011 would charge at its normal rate until almost the end of the charge cycle and then taper briefly (to keep charging without exceeding maximum cell voltage) before considering the charge complete and shutting down the charge process. At first it seemed strange to have the charge rate taper, but keep charging for nearly an hour after I purchased the 2015.
Yes, it seems likely that it is to cram more charge in. We learned of it via the articles that viewtopic.php?f=31&t=21628
references. That might be responsible for a small part of the higher EPA range rating of the '13 to '15 24 kWh Leafs (84 miles at 100% instead of 73).