I'm new here
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I don't go very far in it, all local journeys, shopping etc., averaging 40 miles a week.
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The battery charge indicator never shows more than four bars. Mostly only three.
Welcome and please don't hesitate to ask!
I wouldn't worry too much about the charge level of the HV battery (as long as it permanently is at or above 3 bars).
The system is actually quite clever and normally keeps the charging level between 3 and 7 bars i.e. it is "low cycling" the battery which is best for a long service life. As others have already mentionend it only reaches 10 bars on long(er) downhill cruises.
As for your observation that it hardly goes over 4 bars: I have found that a demand for cabin heat makes the ICE run "needlessly" with regards to HV battery charge level on shorter trips so the charge level doesn't go through its normal cycle.
Instead it may go up and stay up beyond 3 bars for the entire trip.
My "recommendation" is to relax and give Honda's engineers the benefit of the doubt

(imho they did an excellent job!)
Just enjoy the ride!