system 102 for example in one implementation rear end 270 may comprise an end cap including openings for electrical cables to connect among one or more batteries and a vehicle electrical system in another implementation rear end 270 may comprise electrical plugs on an internal surface to receive connections of one or more batteries to connect among the one or more batteries and a vehicle electrical system in yet another implementation rear end 270 may comprise one or more openings not shown to accommodate inlet or outlet ducts for cooling vehicle batteries located in cavity 233 for example air may flow through cavity 233 to cool batteries 220 inlet or outlet ducts may be located in other portions of vehicle battery case 230 such as portions 235 a 235 b 235 c or 235 t for example of course such details of a vehicle battery case or a vehicle battery are merely examples and claimed subject matter is not so limited in an embodiment a method of manufacturing vehicle battery case 230 may comprise forming housing 231 by extruding a polyethylene type material into a shape that includes one or more slides 245 one or more channels 240 or any other feature that may be formed from an extrusion process for example in an alternative embodiment a method of manufacturing vehicle battery case 230 may comprise forming housing 231 by molding a polyethylene type material into a shape that includes one or more slides 245 one or more channels 240 or any other feature that may be formed from a molding process for example though other methods of manufacturing vehicle battery case 230 may be used extruded or molded polyethylene type material may lead to a housing 231 that is relatively strong has relatively low friction.