What is the difference between corporal injury on spouse-Penal Code Section 273.5 and domestic battery-Penal Code Section 243(e)(1)?

Penal Code 243 (e) (1) -simple domestic battery is the least serious offense compared to infliction of corporal injury on spouse-PC 273.5. The prosecution can seek this offense even if you don’t injure your spouse. This is charged as a misdemeanor offense by the prosecution.

Penal Code 273.5 Intentional Infliction of Corporal Injury spouse:

This offense can be filed either as a misdemeanor or as a felony.  This offense is committed if you willfully inflict a corporal ("bodily") injury on your current or former spouse, someone with whom you live or lived, or the parent of your child.

This offense compared to spousal battery above requires a “traumatic injury” to the victim caused by physical force such as marks, bruises, bloody scratches, etc.

The other notable distinction is "intimate partners", under  PC 273.5 intentional infliction of corporal injury can’t be filed against you if you injured your former or current fiancée or someone you are or were dating whereas in PC 243(e)(1), the prosecution can.