She said that, over time, they lose their ability to full charge.
why is the above sentence wrong? FULL is adjective, FULLY is adverb, CHARGE is noun. Isn't it adjective +noun, and adverb+verb(or adjective, or adverb)?
In this case "charge" is a verb. More correctly it is the infinitive verb "to charge". It might be even better to say "[...] ability to charge fully." If you want to use "charge" as a noun you would have to change the sentence to something like this:
She said that, over time, they lose their ability to reach full charge.