Direction : In the question below, a sentence is given with four words highlighted in bold. One  of these four words may either be wrongly spelt or inappropriate in the context of the sentence. Find out the word, which is wrongly spelt or inappropriate, if any. If all the words are correctly spelled and appropriate in the context of the sentence, mark (E) as your answer. 

the world's need for large amounts of portable energy grows at an ever-increasing peace, many innovators have sought to replace current battery technology with something better.