Battery packs for utility vehicle electric drivetrains

A battery assembly for an electric vehicle is provided that has a housing, one or more battery units, and a mounting system. The housing includes a concave shell extending from an upper portion of the housing toward a bottom portion of the housing. The concave shell is disposed around an internal space. A cover is coupled with an edge of the concave shell. The one or more battery units are disposed within the internal space of the housing. The mounting system is for connecting the battery assembly to a vehicle frame.