When I try to use @greenleaf 's code I get the error: src/MAX17048_component.h:23:5: error: 'Wire' was not declared in this scope. Some poking around showed me that most ESPHome components are not using Wire. Any thoughts, anyone?
Apparently custom components like this one are now deprecated: Custom I²C Device — ESPHome
So maybe one of us will get a chance to create an external component for the max17048 and share it here!