"The default charge level is 100% when plugged in."

[BR Blues]

That's Honda's official position on charge levels, as stated in my 2024 Prologue's Owner's Manual. It seems unreasonable for the manufacturer to specify a default level that actually harms the car's battery. Why would the typical Prologue buyer (not the tech-head subset) not heed this? The manual also recommends 80% when "... driving down steep grades ... " in order to "... [provide] room in the battery for regenerative braking ..." Does the question of charge levels need an answer more complicated than this?

 

[Johnstratford]

Seems odd they'd tell you to do something that hurts the battery.
They know most folks aren't gonna be battery experts so they're giving simple rules. And that 80 percent for hills makes sense they want space for the regen to work its magic. Honestly I think they're just trying to keep it easy for everyone. You could dig into the science but for most drivers sticking to the manual probably keeps things simple and safe.