A lift device includes a base assembly, a turntable assembly, and a controller. The base assembly includes multiple base assembly batteries. The turntable assembly is rotatably coupled with the base assembly through a slip ring transmission. The turntable assembly includes multiple turntable assembly batteries. The controller is configured to operate the base assembly batteries to discharge electrical energy to the turntable batteries through the slip ring transmission. The slip ring transmission is configured to both (1) drive the turntable assembly to rotate relative to the base assembly and (2) to electrically and communicably couple electrical components of the base assembly with electrical components of the turntable assembly.