From what I can tell, a partial refresh of the display (updating a smaller portion of the screen) performs less wear on the display than a full refresh, but it can still accumulate over time. Additionally some displays will require a full refresh after a certain number of partial refreshes to deal with ghosting.
I read an article from someone doing a similar project and if you don't do a full refresh every so often then you'll actually wear out the display faster (he burned one out real quick). It actually needs those full refreshes after so many partial updates.
Huh, interesting. I don't know anything about it, but my Kobo Libra has settings for how often to refresh the whole screen (e.g. every N pages, at the end of the chapter, etc.).
it does not matter in practice, let's say you do a full refresh once a second, it would take more than 11 days to do 1 million refreshes, if you do full refresh once a minute, it would take 2 years
Those numbers don't seem high, at all, for me.
Typing would probably cause a refresh more often than every second and even if it's delayed to be once, every second, it's still only 11 days.
For the usage being discussed here, 1 million is extremely low. For its original intended usage, which might cause one to dozens of refreshes per day, it's more than it'll ever need.
For eink reader is more than enough, for digital typewriter eink is not good choice for display, there are high contrast lcd displays with in-pixel memory that can be used