MILWAUKEE, Wis. (WTAQ) - Johnson Controls of suburban Milwaukee asked a judge Wednesday to break up the company’s joint venture with another firm to make hybrid car batteries.

Johnson’s partner, Saft, was also a part of the separation request.

It was filed in a Chancery Court in Delaware. The joint venture was formed in 2006.

It was meant to combine Johnson Controls’ knowledge of the auto industry, and the battery-making talents of Saft. The goal was to become the first in the world to make lithium-ion batteries for hybrids.

Johnson Controls wanted to extend the deal beyond the auto industry, but Saft was apparently satisfied making batteries solely for hybrid and electric vehicles.

Officials said the disagreement was the reason for the effort to split up their partnership.

Saft is involved in its own non-automotive battery projects.