Tesla Inc. on March 15 said it will extend its all-stock offer for battery-maker Maxwell Technologies Inc. until April 2, two weeks later than the original March 19 deadline.

As of market close March 14, Tesla subsidiary Cambria Acquisition Corp. has acquired about 3,094,515 shares.

The offer values each Maxwell common share at $4.75 and was announced Feb. 4. In the same release, Maxwell said its board unanimously recommended and approved the deal. Its directors along with select officers of the company and I2BF Energy Ltd. agreed to tender all of their Maxwell shares, which represent a total of 7.56% of the company.