DETROIT — Electric car company Tesla Inc. is buying Perbix, a Minnesota-based maker of highly automated manufacturing equipment.

Perbix has been a supplier to Tesla for three years. It has built custom machinery for Tesla’s Fremont, California, assembly plant as well as its battery plant in Nevada.

Perbix will continue to be based north of Minneapolis. It currently employs 150 people, but Tesla says it will recruit more.

Tesla didn’t say how much the deal is worth. Company CEO Elon Musk has said he is determined to make Tesla’s factories more efficient, and the machines Perbix makes are part of that effort.

Tesla has made multiple acquisitions in recent years to boost its manufacturing expertise. It bought a Michigan parts stamping plant in 2015 and a German engineering firm in 2016.