A mounting structure for a power storage device includes: a power storage device including a power storage stack and a housing case; a floor member; and a rear bracket. The housing case includes a lower case having a rear wall, and an upper case. The floor member is provided with an attachment portion for attaching the rear bracket. The rear bracket includes a front end portion and a rear end portion that is attached to the attachment portion. The power storage stack is disposed inside the housing case to provide a gap between the power storage stack and the rear wall. The front end portion of the rear bracket is fixed to the rear wall to be located between an upper surface and a lower surface of the power storage stack in an up-down direction.

A vehicle lower structure includes: a battery pack having first and second battery units and a battery cover; and a fuel tank that is arranged on a vehicle rear side to be higher than the first and second battery units. At positions under a floor panel, the first and second battery units are arranged on both sides in a vehicle width direction of a propeller shaft. The battery cover has a coupling section that couples first and second battery accommodation sections. The coupling section couples the first and second battery accommodation sections such that a vehicle rear side thereof is higher than the first and second battery accommodation sections, extends in the vehicle width direction at a position above the propeller shaft, and is arranged next to a vehicle front side of the fuel tank.

A vehicle lower structure includes a battery pack arranged under a floor panel and having: first and second battery units that are separately arranged from each other on both sides in the vehicle width direction of the propeller shaft; and a battery cover. The battery cover has a first battery accommodation section, a second battery accommodation section, and a coupling section that couples the first and second battery accommodation section and extends in the vehicle width direction. The coupling section includes a fragile section between the first and second battery accommodation sections in the vehicle width direction.

A vehicle lower structure includes: first and second battery units that are arranged under a floor panel and on both sides in a vehicle width direction of a propeller shaft; right and left floor frames disposed on a lower surface side of the floor panel. The floor frame has a front inclined section and a width increased section. The first and second battery units are arranged between the width increased sections 52 of the right and left floor frames. A battery-related electrical component, a width of each of which in the vehicle width direction is less than a width of each of the first and second battery units, is arranged between the front inclined sections.

A power supply device mounting structure for a power supply device disposed below a seat disposed in a vehicle interior is provided. The power supply device mounting structure includes a plate member and a contact portion. The plate member is disposed between the power supply device and a seat surface portion of the seat and the plate member covers an upper surface of the power supply device. The contact portion is provided at a position facing an edge portion of the plate member and the contact portion comes into contact with the seat surface portion when a load is input from the seat surface portion.

A battery pack for a vehicle electrical system includes a casing for receiving one or more battery modules. The battery modules are insertable into a casing of the battery pack by sliding couplers along pairs of rails and are securable to the ends of the rails. After insertion, the rails thermally insulate one battery module from other battery modules coupled to the casing. In some examples, a first stiffness or a first mechanical frequency of the casing with the one or more battery modules inserted may differ from a second stiffness or a second mechanical frequency associated with a body of a vehicle or another component associated therewith by a threshold amount. Additionally, the casing may be configured with vents for venting the hot gases, such as those generated by a battery module in a thermal runaway event.

Battery cases are formed such that a small second battery case is disposed on an upper front part of a large first battery case, the second battery case is disposed below a front part of a seat cushion of a rear seat, a recess portion extending in a fore-and-aft direction and having at least part of an exhaust passage member passing therethrough is formed in a lower face of a middle part in a vehicle width direction of the first battery case, battery modules housed in the first battery case are disposed on left and right sides of the recess portion, and a battery module housed in the second battery case is disposed so that a longitudinal direction thereof follows the vehicle width direction. Therefore, it is possible to ensure the headroom for a rear seat by disposing the rear seat at as low a position as possible.

A rear chassis module for a vehicle includes: a rear suspension subframe disposed under a rear floor panel; a pair of front reinforcing members extending from the rear suspension subframe toward the front of the vehicle, and supporting a battery pack; a pair of rear reinforcing members extending from the rear suspension subframe toward the rear of the vehicle, and supporting a fuel tank; a pair of rear floor side members disposed on both sides of the rear floor panel; and a rear crossmember transverse to and connected to the pair of rear floor side members.

A battery pack includes a first battery module, a first battery case accommodating the first battery module, a second battery module, and a second battery case placed on an upper side of the first battery case so as to overlap each other and accommodating the second battery module. The second battery module is fixed to a fastening portion formed on a bottom surface of the second battery case and bulging downward. A hole portion for accommodating the fastening portion is provided on an upper surface of the first battery case at a position overlapping the fastening portion when viewed from above.

A battery pack includes a first battery case accommodating a plurality of cells, and a second battery case laminated above the first battery case and accommodating a plurality of cells. The first battery case has a first through-hole on an upper surface. The second battery case has a second through-hole on a bottom surface which communicates with the first through-hole. The battery pack includes a communication port composed of the first through-hole and the second through-hole, a gas discharge valve which is provided only in either the first battery case or the second battery case and opens when internal pressure of the battery pack is higher than a predetermined value, and a temperature sensor provided on a gas flow path connected to the gas discharge valve.