(Bloomberg) -- Lightning eMotors Inc. shares surged after the company that electrifies commercial vehicles announced a strategic partnership with a Berkshire Hathaway Inc.-backed bus maker..Lightning, whose stock started trading in May after a merger with a blank-check company, will build fully electric powertrains and provide charging products and services to Berkshire’s Forest River Inc., according to a statement Tuesday. The companies said they’ll deploy as many as 7,500 shuttle buses..Lightning shares soared 85% to $11.87 as of 10:11 a.m. in New York. The stock had slumped 26% since the close on May 7, its first day of trading..Forest River will use powertrains from Lightning in Class 4 and 5 shuttle buses it plans to manufacturer at an existing plant in Goshen, Indiana. The companies estimated the potential value of their agreement at $850 million..The deal with a business linked to billionaire Warren Buffett’s firm is a big win for Lightning after a series of setbacks for electric vehicle-related startups that have merged with special-purpose acquisition companies. The manufacturer formerly known as Lightning Hybrids buys commercial-vehicle chassis from companies including Ford Motor Co. and assembles electric versions at its 250,000 square-foot facility in Loveland, Colorado..Forest River, which sells shuttle buses under the Starcraft, Glaval, and Champion brands, plans to market the battery-powered vehicles through its network of more than 100 dealerships in the U.S. and Canada..©2021 Bloomberg L.P.