The principles of Integral Safety, in particular accident safety, apply regardless of the platform. Like all other Mercedes, the EQS therefore features a rigid passenger cell, special deformation zones and state-of-the-art restraint systems. PRE-SAFE® is standard.
The fact that the EQS is based on an all-electric architecture also opened up new design possibilities for its safety concept. Thus, the installation space for the battery could be favourably selected in a crash-protected area in the underbody (for details on battery safety, see separate chapter). And because there is no large engine block on board, the behaviour in a frontal crash could be modelled even better. In addition to the standard crash tests, the car's performance in various additional load situations was verified and extensive component tests carried out at the Vehicle Safety Technology Centre (TFS).
High-voltage system: automatic shut-down in accidents
The battery, high-voltage (HV) cables and other HV components have been designed and protected in such a way that they meet Mercedes-Benz's high safety requirements in the event of an accident.
The multi-stage protection concept of the high-voltage (HV) system has already proven itself in the other Mercedes-EQ models. In case of danger, it can be automatically switched off and disconnected from the battery. A distinction is made between a reversible and an irreversible cut-off. In the case of a reversible shut-down, which occurs in less severe accidents, it is possible to switch the high-voltage system back on if a prior insulation measurement detects no faults. This means that vehicles still capable of being driven can continue their journey. Only in the case of very severe accidents, where the vehicle is usually incapable of being driven anyway, is the high-voltage system shut down irreversibly and unable to be activated without repair. When shutting down, there is a provision to ensure that within a few seconds there is no residual voltage in the high-voltage system outside the battery that could cause injury.
There are also shut-down points where emergency teams can deactivate the high-voltage system manually. In addition, the EQS has crash monitoring when stationary (during DC charging) as standard.
Acoustic Vehicle Alert System: special sound as a warning for pedestrians
The electric-car-specific innovations also include an Acoustic Vehicle Alert System (standard). This makes it easier for pedestrians to notice the EQS at low speeds. One sound generator sits weatherproof in the front right wheel arch and in the rear underbody respectively. An EQ-specific sound is generated up to a vehicle speed of approx. 30 km/h. It becomes louder and higher with increasing speed. This change allows conclusions to be drawn about the driving status (braking/acceleration).
Above 20 km/h, the sound is gradually faded out, since above this threshold the vehicle can be perceived via the then dominant rolling and wind noises. If the speed drops back to 30 km/h, the sound is faded in again. When reversing, an intuitively recognisable interval tone sounds regardless of the speed.
Modern restraint systems: from B for belt airbag to W for window airbag
In addition to driver and front passenger airbags, a knee airbag on the driver's side is also standard. It protects the legs from contact with the steering column or instrument panel in a severe frontal crash. This can prevent or lessen the severity of injuries.
The standard window airbags can reduce the risk of head impact with the side window or penetrating objects. In the event of a serious side collision, the window airbag on the side of the impact extends from the A- to the C-pillar like a curtain over the front and rear side windows. If a rollover is detected, the window airbags can be activated on both sides.
Vehicles for Europe also have a centre airbag to meet new rating requirements. During a severe side impact, it positions itself between the driver and front passenger seat, reducing the risk of their heads making contact. It is integrated into the driver's seat backrest in the middle of the vehicle.
In conjunction with power rear seats with memory function, the EQS is equipped with side airbags in the rear. They protect the chest area on the outer rear seats in the event of a severe side impact and supplement the protection provided by the standard window airbags.
The belt airbags (optional extra) ensure that passengers in the outer rear seats are particularly well protected in the event of a severe frontal collision. The inflatable webbing widens its contact area in the chest and shoulder area almost threefold when triggered. This can reduce the loads acting on the occupants' thorax.
In conjunction with the Exclusive nappa leather Package, the EQS has designer belt buckles at the front and rear. They support buckling up, because the lights of the belt buckle pulsate at that time. When stationary and at low speed, the lights are solid.
The EQS has i-Size child seat attachments as standard on the two outer rear seats. With two anchors each between the seat back and the seat cushion, corresponding child seats are installed particularly quickly and securely. Top tether attachment points behind the rear head restraints provide additional support.
PRE-SAFE®: precautionary protection as standard
The PRE-SAFE® preventive occupant protection system is fitted as standard in the EQS. Together with the familiar precautionary measures in the event of a potential frontal and rear-end crash, PRE-SAFE® Impulse Side (available in conjunction with the Driving Assistance Package Plus or the Driving Assistance Package with DRIVE PILOT) forms a kind of virtual crumple zone that extends around the vehicle.
As only a limited crumple zone is available in a side impact, PRE-SAFE® Impulse Side (availability depending on selected equipment) can move the affected driver or front passenger away from the danger even before the crash as soon as the system detects that a side collision is immediately imminent. For this purpose, air chambers in the side bolsters of the front seat backrest are inflated in fractions of a second.