Tesla will buy Maxwell Technology for $4.75 a share, a 55% premium to Maxwell’s share price last Friday.

Maxwell is an energy storage and power delivery solutions company whose main products are supercapacitors. Tesla CEO believes that super capacitors will be the key to future electric vehicles.

The directors and senior executives of Maxwell I2BF Energy will transfer all of their shares, accounting for 7.56% of the outstanding shares. The transaction will be completed in the second quarter this year.