Why has the battery icon disappeared on my Chromebook?

Episode 1339 (1:43:09)

Carol from Simi Valley, CA
Dell Chromebook 13

Carol has an HP Chromebook and her battery icon has vanished. She can't get it back. Leo says it's likely a bad battery and HP should replace it. They're wasting her time if they're refusing to replace it when it's under warranty. If it's not the battery, there still could be a physical issue. She should send the entire computer back and get the Dell Chromebook 13.