Keystone Mountaineer, headquartered in the Pittsburgh area, provides services primarily to the mines of the northern Appalachian region.
"We believe that with this acquisition EnerSys will be able to leverage our existing technology to enhance our position in the global mining market," EnerSys executive vice president Americas John Shea said.
"With our global product portfolio, which includes innovative mining support products, we believe we can continue to build on the strong reputation of Keystone Mountaineer."
Financial details of the deal were not released.
EnerSys, a public company headquartered in the eastern Pennsylvania town of Reading, sells products under the two umbrellas of reserve power and motive power, the latter including mining solutions EnForcer, Express, General Battery and EnerSys Ironclad.
