If you're talking about the big high voltage battery, the 62 kWh Leaf Plus which began w/model year '19 is too new for us to know how it's holding up from a degradation POV.
The 40 kWh batteries in '18+ non-Plus Leafs seems to be holding up pretty well from a degradation, POV, so far.
By "problems", are you referring to degradation?
