Hey santi0711,
We understand you're concerned about Apple Maps showing up in Screen Time as being used more frequently than you expected. We're happy to help.
You mentioned using CarPlay and it wouldn't be unexpected for it to always be on while using CarPlay. You also mentioned being concerned about battery usage. Screen Time will provide no information on whether or not it's using up battery, so the best place to check for this, would instead be to go to Settings > Battery and review your usage here. If Maps isn't a top contributor to battery usage, you've likely got nothing to worry about.
For more info on reviewing your battery usage, check out: About the battery usage on your iPhone, iPad, and iPod touch
We hope this information helps out.
Take care!