charge up vs prepare

charge up

verb
  • To motivate, to instill someone with determination. 

  • To recharge, to give electrical power to something. 

  • To deliberately infect an individual with HIV as part of bug-chasing. 

prepare

verb
  • To make oneself ready; to get ready, make preparation. 

  • To make ready for a specific future purpose; to set up; to assemble or equip. 

  • To produce or make by combining elements; to synthesize, compound. 

  • To make ready for eating or drinking; to cook. 

How often have the words charge up and prepare occurred in a corpus of books? (source: Google Ngram Viewer )