A power system for an electric vehicle, the power system comprising: a firewall positioned between an engine compartment and a passenger compartment of the electric vehicle; a floor structure of the electric vehicle coupled with the firewall, the floor structure defining an aperture between the firewall and a central support beam of the floor structure; a battery assembly configured to mount with an underside of the floor structure, the battery assembly comprising: at least one battery; and a battery connector housing, the battery connector housing being configured to house at least one battery connector therein, the battery connector housing defining at least one electric connector configured to couple with at least one electric system of the electric vehicle, the battery connector housing being configured to be inserted within the aperture of the floor structure such that at least a portion of the battery connector housing extends above the floor structure; and a rigid tunnel coupled with the firewall, the floor structure, and the central support beam, the rigid tunnel being configured to cover the portion of the battery connector housing that extends above the floor structure such that the passenger compartment is sealed from the battery connector housing; characterized in that the floor structure comprises a sealing element protruding upward and contacting a portion of the rigid tunnel between the battery connector housing and the central support beam, the sealing element having a shape corresponding to the rigid tunnel. a firewall positioned between an engine compartment and a passenger compartment of the electric vehicle; a floor structure of the electric vehicle coupled with the firewall, the floor structure defining an aperture between the firewall and a central support beam of the floor structure; a battery assembly configured to mount with an underside of the floor structure, the battery assembly comprising: at least one battery; and a battery connector housing, the battery connector housing being configured to house at least one battery connector therein, the battery connector housing defining at least one electric connector configured to couple with at least one electric system of the electric vehicle, the battery connector housing being configured to be inserted within the aperture of the floor structure such that at least a portion of the battery connector housing extends above the floor structure; and at least one battery; and a battery connector housing, the battery connector housing being configured to house at least one battery connector therein, the battery connector housing defining at least one electric connector configured to couple with at least one electric system of the electric vehicle, the battery connector housing being configured to be inserted within the aperture of the floor structure such that at least a portion of the battery connector housing extends above the floor structure; and a rigid tunnel coupled with the firewall, the floor structure, and the central support beam, the rigid tunnel being configured to cover the portion of the battery connector housing that extends above the floor structure such that the passenger compartment is sealed from the battery connector housing; characterized in that the floor structure comprises a sealing element protruding upward and contacting a portion of the rigid tunnel between the battery connector housing and the central support beam, the sealing element having a shape corresponding to the rigid tunnel.