WO2018189677A2

WO2018189677A2 - Electrical vehicle and battery unit arrangement for electrical vehicle

Info

Publication number: WO2018189677A2
Application number: PCT/IB2018/052505
Authority: WO
Inventors: Albert Lam
Original assignee: Detroit Electric Ev Limited
Priority date: 2017-04-10
Filing date: 2018-04-10
Publication date: 2018-10-18
Also published as: GB2556351B; GB2556351A; WO2018189677A3; GB201705780D0

Abstract

Disclosed is an electrical vehicle including a vehicle chassis, front and rear sets of wheels, a battery unit arrangement and an electric motor arrangement that is operable to receive electrical power from the battery unit arrangement to propel the electrical vehicle, and a vehicle cabin including a seat arrangement for accommodating one or more users of the electrical vehicle. The battery unit arrangement is accommodated in at least a floor region of the electrical vehicle beneath the vehicle cabin, and the electrical vehicle includes an engagement mechanism for retaining the battery unit arrangement onto the vehicle chassis, wherein the engagement mechanism is releasable for repairing or replacing the battery unit arrangement, and the engagement mechanism includes an emergency release element for automatically releasing the battery unit arrangement in an event of the electrical vehicle experiencing a collision.

Description

ELECTRICAL VEHICLE AND BATTERY UNIT ARRANGEMENT FOR

ELECTRICAL VEHICLE

TECHNICAL FIELD The present disclosure relates to electrical vehicles. Moreover, the present disclosure concerns battery unit arrangements for aforementioned electrical vehicles. Additionally, the present disclosure is concerned with methods of employing the aforesaid battery unit arrangements. Furthermore, the present disclosure relates to software products stored on machine-readable data storage carrier and executable upon computing hardware for implementing aforesaid methods.

BACKGROUND

Conventionally, pure electrical vehicles and hybrid vehicles (wherein the hybrid vehicles include a combination of electrical motor and internal combustion engine arrangements) are well known. Recently, improvements in lithium polymer battery technologies have enabled contemporary electrical vehicles to provide a driving range per full battery charge that is comparable to conventional internal combustion engine vehicles provided with fuel tanks full of combustible fuel.

Usually, for reasons of providing satisfactory vehicle handling performance and safety, it is necessary for the battery units to be mounted in a region between front and rear wheel axles of the electrical vehicles, and preferably at a location that results in a low centre-of- gravity for the electrical vehicles. Additionally, it is known to mount battery units in a rear boot region and within a floor region of high performance electrical vehicles. However, for reducing manufacturing costs, and improving safety, it is generally not desirable to employ multiple battery units within an electrical vehicle. Additionally, other design constraints pertain for such electrical vehicles, such as accessibility for repairing and/or replacing the battery units, and also providing cooling to the battery units when high-performance is desired. Additionally, the location of the battery units should enable a reduction of risk of electrical shock to passengers of the electrical vehicle, for example, in an event of collision of the electrical vehicle.

From the foregoing, it will be appreciated that designing and mounting a battery unit in an electrical vehicle is not a trivial design exercise, and many different conflicting constraints have to be satisfied.

SUMMARY

The present disclosure seeks to provide an improved electrical vehicle, wherein a battery unit arrangement thereof is mounted in an improved manner onto a chassis of the electrical vehicle. The present disclosure also seeks to provide an improved battery unit arrangement for an electrical vehicle.

Moreover, the present disclosure seeks to provide a method of employing a battery unit arrangement in an electrical vehicle.

The present disclosure also seeks to provide a software product recording for implementing a method of employing a battery unit arrangement in an electrical vehicle.

According to a first aspect, there is provided an electrical vehicle including a vehicle chassis, front and rear sets of wheels, a battery unit arrangement and an electric motor arrangement that is operable to receive electrical power from the battery unit arrangement to propel the electrical vehicle, and a vehicle cabin including a seat arrangement for accommodating one or more users of the electrical vehicle, characterized in that:

(i) the battery unit arrangement is accommodated in at least a floor region of the electrical vehicle beneath the vehicle cabin; and (ii) the electrical vehicle includes an engagement mechanism for retaining the battery unit arrangement onto the vehicle chassis, wherein the engagement mechanism is releasable for repairing or replacing the battery unit arrangement, and the engagement mechanism includes an emergency release element for automatically releasing the battery unit arrangement in an event of the electrical vehicle experiencing a collision.

According to a second aspect, there is provided a battery unit arrangement for an electrical vehicle, wherein the electrical vehicle includes a vehicle chassis, front and rear sets of wheels, a battery unit arrangement and an electric motor arrangement that is operable to receive electrical power from the battery unit arrangement to propel the electrical vehicle, and a vehicle cabin including a seat arrangement for accommodating one or more users of the electrical vehicle, characterized in that:

(i) the battery unit arrangement is operable to be accommodated in at least a floor region of the electrical vehicle beneath the vehicle cabin; and

(ii) the electrical vehicle includes an engagement mechanism for retaining the battery unit arrangement onto the vehicle chassis, wherein the engagement mechanism is releasable for repairing or replacing the battery unit arrangement, and the engagement mechanism includes an emergency release element for automatically releasing the battery unit arrangement in an event of the electrical vehicle experiencing a collision. According to a third aspect, there is provided a method of employing a battery unit arrangement, characterized in that the method includes: (i) accommodating the battery unit arrangement in at least a floor region of the electrical vehicle beneath the vehicle cabin; and (ii) employing an engagement mechanism for retaining the battery unit arrangement onto the chassis, wherein the engagement mechanism is releasable for repairing or replacing the battery unit arrangement, and arranging for the engagement mechanism to include an emergency release element for automatically releasing the battery arrangement in an event of the electrical vehicle experiencing a collision.

According to a fourth aspect, there is provided a software product recording on machine-readable data storage media, characterized in that the software product is executable upon computing hardware for implementing a method of employing a battery unit arrangement.

It will be appreciated that features of the present disclosure are susceptible to being combined in various combinations without departing from the scope of the present disclosure as defined by the appended claims. The present invention is included in the general business context, which aims to substitute vehicles powered by traditional fuels, for example gasoline or diesel, by electric vehicles. In particular, the present invention is intended for use in electric vehicles used within cities, which can be highly beneficial to the local environment due to significant reduction of gaseous emissions as well as significant reduction of noise. Overall environmental benefits can also be significant when electric vehicles are charged from renewable energy sources.

BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the present disclosure will now be described, by way of example only, with reference to the following diagrams wherein :

FIG. 1 is a schematic illustration of an electrical vehicle, in accordance with an embodiment of the present disclosure;

FIGs. 2 and 3 are schematic illustrations of the electrical vehicle of FIG.

1 having experienced a frontal collision, in accordance with an embodiment with the present disclosure;

FIG. 4 is a schematic illustration of an engagement mechanism for retaining the battery unit arrangement onto a vehicle chassis, in accordance with an embodiment of the present disclosure;

FIG. 5 is a schematic illustration of an engagement mechanism in an electrical vehicle having experienced a frontal collision (such as the electrical vehicle of FIG. 2), in accordance with an embodiment of the present disclosure;

FIG. 6 is a schematic illustration of an electrical vehicle, in accordance with another embodiment of the present disclosure;

FIGs. 7 and 8 are schematic illustrations of the electrical vehicle of FIG.

6 having experienced a frontal collision, in accordance with an embodiment with the present disclosure;

FIG. 9 is a schematic illustration of an electrical vehicle, in accordance with yet another embodiment of the present disclosure;

FIG. 10 is a schematic illustration of a battery unit arrangement, in accordance with an embodiment of the present disclosure; FIG. 11 is a schematic illustration of a workshop for servicing a battery unit arrangement of an electrical vehicle, in accordance with an embodiment of the present disclosure; and

FIG. 12 is an illustration of steps of a method of employing a battery unit arrangement in an electrical vehicle, in accordance with an embodiment of the present disclosure.

In the accompanying drawings, an underlined number is employed to represent an item over which the underlined number is positioned or an item to which the underlined number is adjacent. A non-underlined number relates to an item identified by a line linking the non-underlined number to the item. When a number is non-underlined and accompanied by an associated arrow, the non-underlined number is used to identify a general item at which the arrow is pointing.

DETAILED DESCRIPTION OF EMBODIMENTS In overview, embodiments of the present disclosure are concerned with electrical vehicles, wherein their battery units are mounted substantially in a floor region of the electrical vehicles, and optionally extend into a region behind passenger seats of the electrical vehicles. The battery unit is provided with a mounting arrangement that is operable to disengage the battery unit in a severe crash situation or when required for maintenance and/or replacement purposes. The disclosure is illustrated in respect of a severe frontal crash situation. However, the principles underlying the disclosure are applicable to rear impact or side impact situations. In an embodiment of the disclosure, an emergency release element is operable to be triggered by a structural element of a region of the vehicle chassis, the structural element being designed to undergo a submarining trajectory (Α-Α') in the event of the electrical vehicle (100) experiencing the collision. Such a region of the vehicle chassis may be susceptible to deform due to the impact of the collision.

Optionally, under severe crash cond itions, when released from the electrical vehicle, the battery unit is operable to separate into multiple sub-units that are less hazardous.

Referring to FIG. 1, illustrated is a schematic illustration of an electrical vehicle 100, in accordance with an embodiment of the present disclosure. The electrical vehicle 100 includes a vehicle chassis (not shown), front and rear sets of wheels 110, 120, a battery unit arrangement 130 and an electric motor arrangement 140 that is operable to receive electrical power from the battery unit arrangement 130 to propel the electrical vehicle 100. Furthermore, the electrical vehicle 100 includes a vehicle cabin 150 including a seat arrangement 160 for accommodating one or more users of the electrical vehicle 100. As shown, the battery unit arrangement 130 is accommodated in at least a floor region of the electrical vehicle 100 beneath the vehicle cabin 150. Additionally, the electrical vehicle 100 includes an engagement mechanism for retaining the battery unit arrangement 130 onto the vehicle chassis, wherein the engagement mechanism is releasable for repairing or replacing the battery unit arrangement 130. The engagement mechanism includes an emergency release element 170 for automatically releasing the battery unit arrangement 130 in an event of the electrical vehicle 100 experiencing a frontal collision.

Referring now to FIGs. 2 and 3, illustrated are schematic illustrations of the electrical vehicle 100 having experienced a frontal collision, in accordance with an embod iment with the present disclosure. As shown, the emergency release element 170 has been released and consequently, the battery unit arrangement 130 has been disengaged from the vehicle chassis. Referring to FIG. 4, illustrated is a schematic illustration of an engagement mechanism 400 for retaining the battery unit arrangement 130 onto a vehicle chassis, in accordance with an embodiment of the present disclosure. As shown, the engagement mechanism 400 includes the emergency release element 170 for automatically releasing the battery unit arrangement 130 in an event of an electrical vehicle (such as the electrical vehicle 100 of FIG. 1) experiencing a frontal collision.

Furthermore, the emergency release element 170 is operable to be triggered by a structural element 430 of a frontal region of the vehicle chassis, the structural element being designed to undergo a submarining trajectory A-A' in the event of the electrical vehicle experiencing a frontal collision. As shown, the submarining trajectory A-A' refers to a combined downward movement (along top-bottom direction of the electrical vehicle) and rearward movement (along a direction parallel to an elongate front-rear axis of the electrical vehicle) of the structural element 430, resulting in an inclined movement thereof (such as a submarine vessel executing a downward movement while going subsurface and simultaneously moving rearward). It will be appreciated that the crumple zone element 440 is operable to hold the structural element 430 in its place. Furthermore, the crumple zone element 440 ensures movement of the structural element 430 along the submarining trajectory A-A' upon collision. Specifically, the crumple zone element 440 may comprise a slope in lower part thereof to complement slope in the structural element 430 and thus ensures the submarining trajectory thereof.

Additionally, the structural element 430 is associated with a crumple zone element 440 that is accommodated in a crumple zone of the electrical vehicle. It will be appreciated that the electrical vehicle may comprise a crumple zone including one or more crumple zone elements 440 and other types of rigid vehicle chassis elements. Furthermore, the one or more crumple zone elements 440 may be configured to partially absorb energy (such as kinetic energy) of a collision. In such an instance, the absorption of the energy may allow prevention of severe injuries to one or more users, namely passengers, of the electrical vehicle. The severity of the impact required to trigger the emergency release element may be determined by the rigidity of the crumple zone.

Referring to FIG. 5, illustrated is a schematic illustration of an engagement mechanism 400 in an electrical vehicle having experienced a frontal collision (such as the electrical vehicle of FIG. 2), in accordance with an embodiment of the present disclosure. As shown, the crumple zone element 440 has been subjected to impact of the frontal collision of the electrical vehicle and has been crumpled (or crushed). Consequently, the structural element 430 has been released and has executed a movement along the submarining trajectory A-A' and thereby, triggering the emergency release element 170. Additionally, in response to triggering of the emergency release element 170, the battery unit arrangement 130 has been released from the vehicle chassis.

It will be appreciated that the crumple zone element 440 shown in the FIGs. 4 and 5 is for illustrative purposes only and should not limit the scope of the present disclosure. Optionally, the crumple zone element 440 may comprise a plurality of sub-units therein, wherein crumpling of one or more sub-units may release the structural element 430.

In an implementation of the present disclosure, the electrical vehicle 100 (of FIG. 1) may experience a front collision. Consequently, the structural element 430 may experience an impact force from the frontal collision. As a result of the impact force, the structural element 430, in contact with the crumple zone element 440, imparts a corresponding reaction force to the crumple zone element 440 and crumples it. Consequently, the structural element 430 is released.

It will be appreciated that the electrical vehicle may comprise a crumple zone in other parts thereof, such as a rear of the electrical vehicle. In an example, the engagement mechanism 400 may be operable to automatically release the battery unit arrangement 130 in an event of the electrical vehicle experiencing a collision from the rear of the electrical vehicle. Thus, a similar structural element to that used for frontal impact may be constructed to be in contact with a crumple zone in a rear region of the electric vehicle. Upon severe impact, it would undergo a downward and forward movement of the structural element resulting in an inclined movement thereof (such as a submarine vessel executing a downward movement while going subsurface and simultaneously moving forward), to trigger the emergency release element 170. In some electrical vehicles, a crumple zone is a side region of the electric vehicle, and a corresponding side impact structural element could be constructed to release the emergency release element upon severe side impact from the left or right-hand side.

Optionally, the crumple zone element may 440 have a compressive strength that is configured to resist minor impact. For example, the crumple zone element 440 may not crumple in an event of the electrical vehicle bumping into an object while reversing (at low speed) the electrical vehicle.

Optionally, the structural element 430 is structurally connected to the crumple zone element 440 at the front of the electric vehicle 100 through a rod placed between both the front wheels 110 and the release element 170 is connected to the battery unit arrangement 130.

Optionally, the emergency release element 170 comprises at least one of a mechanical arrangement, an electromechanical arrangement, and/or an electromagnetic arrangement. For example, the emergency release element 170 comprises a mechanical arrangement such as a spring-loaded quick-release mechanism. In another example, the emergency release element 170 comprises an electromechanical arrangement such as a high speed electric actuator. In yet another example, the emergency release element 170 comprises an electromagnetic arrangement such as an electromagnetic latch.

Referring to FIG. 6, illustrated is a schematic illustration of an electrical vehicle, such as the electrical vehicle 100, in accordance with another embod iment of the present disclosure. As shown, a battery unit arrangement is implemented as a battery unit 610 that forms at least a part of the floor of the electrical vehicle 100 and extends to a region behind the seating arrangement 160 of the cabin 150 of the electrical vehicle 100. Optionally, an upper outer surface 620 of the battery unit 610 forms a floor surface of the cabin 150 of the electrical vehicle 100. In an example, the upper outer surface 620 is provided with carpeting (not shown), such that removal of the battery unit 610 creates a hole (shown in FIG. 8) in the floor of the cabin 150. Furthermore, as shown, the battery unit 610 has substantially an L-shape. Optionally, a vertex of the L-shape has an angle of more than 90° . For example, the vertex of the L-shape may have an angle of 135 ° .

Referring now to FIGs. 7 and 8, illustrated are schematic illustrations of the electrical vehicle 100 of FIG. 6 having experienced a frontal collision, in accordance with an embodiment with the present disclosure. As shown, an emergency release element 630 has been released and in response thereto, the battery unit arrangement 610 has been disengaged from the vehicle chassis.

In an implementation when the battery unit arrangement 610 has the substantially L-shape, a horizontal section of the battery unit arrangement 610 may be detach from the inclined section thereof in an event of frontal collision of the electrical vehicle 100. Specifically, the horizontal section may disengage from the vehicle chassis first followed by disengagement of the inclined section from the vehicle chassis. Consequently, the horizontal section of the battery unit arrangement 610 may fall to the ground prior to the inclined portion falling on top thereof.

Referring to FIG. 9, illustrated is a schematic illustration of an electrical vehicle, such as the electrical vehicle 100 of FIG. 6, in accordance with yet another embodiment of the present disclosure. Specifically, FIG. 9 illustrates a schematic illustration of the battery unit arrangement 610, for the electrical vehicle 100, which is operable to be accommodated in at least a floor region of the electrical vehicle 100 beneath the vehicle cabin 150. The electrical vehicle 100 includes an engagement mechanism for retaining the battery unit arrangement 610 onto the vehicle chassis, wherein the engagement mechanism is releasable for repairing or replacing the battery unit arrangement 610, and the engagement mechanism includes an emergency release element 630 for automatically releasing the battery unit arrangement 610 in an event of the electrical vehicle 100 experiencing a frontal collision. Optionally, the engagement mechanism is operatively coupled to a sensor arrangement 910 that is capable of sensing the event of the electrical vehicle 100 experiencing the frontal collision. In an embod iment, the sensor arrangement 910 includes a crash sensor. As shown, the sensor arrangement 910 is operatively coupled to a controller 920, wherein the controller 920 is operable to instruct the emergency release element 630 to release the battery unit arrangement 610 based on a sensed signal from the sensor arrangement 910. In an embodiment, the emergency release element 630 comprises at least one of an electromechanical arrangement and/or an electromagnetic arrangement (as described herein above). Optionally, the sensor arrangement 910 and the controller 920 may be part of a Battery Management System (BMS) of the electrical vehicle 100.

Optionally, the crumple zone element 440 is also provided with an electromagnetic actuator which will move the crumple zone element 440 to allow the structural element 430 to follow the trajectory A-A' in order to trigger the release element 170, when it will get a signal from a sensor arrangement 910 in the event of the frontal collision.

Referring to FIG. 10, illustrated is a schematic illustration of a battery unit arrangement 610, in accordance with an embodiment of the present disclosure. As shown, the battery unit arrangement 610 is implemented as a battery unit comprising separable battery sub-units 1010 that are configured to accommodate battery modules (not shown), wherein each battery sub-unit 1010 comprises an access panel 1020. In an event of a collision, the battery sub-units 1010 may be operable to separate from each other to spatially separated individual battery sub-units 1010. In an embod iment, each battery sub-unit 1010 may have a terminal (electrical) potential that is sufficiently low to avoid being a safety hazard . For example, each battery sub-unit 1010 may have a terminal potential of less than 100 Volts. In such example, each battery sub-unit 1010 may be provided with a contactor that is further connected to a main contactor of the battery unit arrangement 610, wherein the contactors of the battery sub-units 1010 are operable to disconnect from the main contactor in the event of collision. It may be appreciated that in the event of a collision (such as an accident), electrical power connections to the battery unit arrangement 610 and other connections such as pipes carrying liquid coolant from a cooling arrangement, are configured to be rapid ly released to reduce a risk of electrical shock to one or more users (namely passengers) of the electrical vehicle. Optionally, contactors within the battery unit arrangement 610 are switched to isolate power terminals of the battery unit arrangement 610, for example in an event of a major fault developing and/or a crash situation occurring .

It will be appreciated that the access panels 1020 of each battery sub- unit 1010 may enable a battery module included therein to be serviced (such as repaired or replaced) without needing to demount the entire battery unit arrangement 610 from the electrical vehicle. For example, a serviceman may be only required to unscrew one or more screws 1030 included in the access panel 1020 to open the access panel and perform the required servicing . Optionally, the access panels 1020 may be watertight. It will be appreciated that the watertight nature of the access panels 1020 may enable the battery unit arrangement 610 to withstand water exposure in an event that water is used to extinguish fire caused by collision of the electrical vehicle (such as collision with a conventional internal combustion engine vehicle that may cause flammable hydrocarbon fuel included in a fuel tank of the conventional internal combustion engine vehicle to leak and subsequently ignite).

Referring to FIG. 11, illustrated is a schematic illustration of a workshop 1100 for servicing a battery unit arrangement of an electrical vehicle (such as the battery unit arrangement 610 of the electrical vehicle 600 of FIG. 6), in accordance with an embodiment of the present disclosure. As shown, the workshop 1100 includes a service pit 1110 comprising a platform 1120. It will be appreciated that the battery unit arrangement 610 may be released from the electrical vehicle 100 and lowered onto the platform 1120 for servicing of the battery unit arrangement 610. Alternatively, the battery unit arrangement 610 may comprise access panels on the underside thereof to allow servicing to be performed without needing to demount the battery unit arrangement 610 from the electrical vehicle 100. Referring to FIG. 12, illustrated are steps of a method 1200 of employing a battery unit arrangement for an electrical vehicle, in accordance with an embodiment of the present disclosure. At a step 1210, the battery unit arrangement is accommodated in at least a floor region of the electrical vehicle beneath a vehicle cabin. At a step 1220, an engagement mechanism is provided for retaining the battery unit arrangement onto the vehicle chassis, wherein the engagement mechanism is releasable for repairing or replacing the battery unit arrangement and arranging for the engagement mechanism to include an emergency release element for automatically releasing the battery unit arrangement in an event of the electrical vehicle experiencing a collision.

The steps 1210 to 1220 are only illustrative and other alternatives can also be provided where one or more steps are added, one or more steps are removed, or one or more steps are provided in a different sequence without departing from the scope of the claims herein. For example, the method may also include the steps of receiving information pertaining to an electrical vehicle experiencing a collision and fu rther, releasing a battery unit arrangement of the electrical vehicle in the event of the electrical vehicle experiencing a collision.

Furthermore, the method of employing the battery unit arrangement 610 is implemented on a software product recording on machine- readable data storage media, characterized in that the software product is executable upon computing hardware. For example, the software product may be a data processing system of the electrical vehicle 600 (referred to as "Software Application Management and Infotainment" System or ⁿSAMI") . In an example, the data processing system may be operable to process the sensed signal from the sensor arrangement 910 to obtain information indicative of an event of the electrical vehicle 600 having experienced a collision. In such example, the data processing system may be operable to transmit a signal to the controller 920 to instruct further the emergency release element 630 to release the battery unit arrangement 610. In another example, the data processing system may be operable to receive information related to an event of an electrical vehicle 600 experiencing a collision and consequently, inform emergency authorities (such as a first responder including fire-fighters, ambulance or police) about the collision.

The engagement mechanism of the present disclosure is operable to release the battery unit arrangement in an event of a collision (such as an accident) and may provide one or more users of the electrical vehicle with improved safety. For example, spatially isolating the battery unit arrangement and the electrical vehicle carrying one or more passengers may reduce a risk of electrical shock to the passengers from the battery unit arrangement and/or electrical power connections coupled to the battery unit. Additionally, the battery unit arrangement comprising separable battery sub-units that are operable to separate into individual spatially isolated components, further reduces the risk of electrical shock. Moreover, the battery unit arrangement is installed from underneath the electrical vehicle and allows the battery unit arrangement to be released using the engagement mechanism. Such an arrangement of the battery unit allows for repairing and/or replacing the battery unit in a time-efficient manner and with reduced effort. Optionally, each battery sub-unit is provided with an access panel for allowing individual battery modules to be serviced without disassembling the entire battery unit arrangement and/or demounting the entire battery unit arrangement from the electrical vehicle.

Modifications to embodiments of the present disclosure described in the foregoing are possible without departing from the scope of the present disclosure as defined by the accompanying claims. Expressions such as "including", "comprising", "incorporating", "have", "is" used to describe and claim the present disclosure are intended to be construed in a nonexclusive manner, namely allowing for items, components or elements not explicitly described also to be present. Reference to the singular is also to be construed to relate to the plural.

Claims

1. An electrical vehicle (100) including a vehicle chassis, front and rear sets of wheels (110, 120), a battery unit arrangement (130) and an electric motor arrangement (140) that is operable to receive electrical power from the battery unit arrangement (130) to propel the electrical vehicle (100), and a vehicle cabin (150) including a seat arrangement (160) for accommodating one or more users of the electrical vehicle (100), characterized in that:

(i) the battery unit arrangement (130) is accommodated in at least a floor region of the electrical vehicle (100) beneath the vehicle cabin (150); and

(ii) the electrical vehicle (100) includes an engagement mechanism (400) for retaining the battery unit arrangement (130) onto the vehicle chassis, wherein the engagement mechanism (400) is releasable for repairing or replacing the battery unit arrangement (130), and the engagement mechanism (400) includes an emergency release element (170) for automatically releasing the battery unit arrangement (130) in an event of the electrical vehicle (100) experiencing a collision.

2. An electrical vehicle (100) of claim 1, characterized in that the emergency release element (170) is operable to be triggered by a structural element (430) of a region of the vehicle chassis, the structural element being designed to undergo a submarining trajectory (Α-Α') in the event of the electrical vehicle (100) experiencing the collision.

3. An electrical vehicle (100) of claim 2, characterized in that the engagement mechanism (400) includes an emergency release element (170) that is operable to be triggered by a structural element (430) of a frontal region of the vehicle chassis for automatically releasing the battery unit arrangement (130) in an event of the electrical vehicle (100) experiencing a frontal collision.

4. An electrical vehicle (100) of claim 2 or claim 3, characterized in that the engagement mechanism (400) includes an emergency release element (170) that is operable to be triggered by a structural element (430) of a rear region of the vehicle chassis for automatically releasing the battery unit arrangement (130) in an event of the electrical vehicle (100) experiencing a collision from the rear.

5. An electrical vehicle (100) of claim 1 or 2, characterized in that the emergency release element (170) comprises at least one of: a mechanical arrangement, an electromechanical arrangement, an electromagnetic arrangement.

6. An electrical vehicle (100) of claim 2, characterized in that the structural element (430) is associated with a crumple zone element (440) and accommodated in a crumple zone of the electrical vehicle (100).

7. An electrical vehicle (100) of claim 1 or 2, characterized in that the battery unit arrangement (130) is implemented as a battery unit (610) that forms at least a part of the floor of the electrical vehicle (100) and extends to a region behind the seating arrangement (160) of the cabin (150) of the electrical vehicle (100).

8. An electrical vehicle (100) of claim 7, characterized in that the battery unit (610) has substantially an L-shape.

9. An electrical vehicle (100) of claim 8, characterized in that a vertex of the L-shape has an angle of more than 90° .

10. A battery unit arrangement (610) for an electrical vehicle (100), wherein the electrical vehicle (100) includes a vehicle chassis, front and rear sets of wheels (110, 120), a battery unit arrangement (610) and an electric motor arrangement (140) that is operable to receive electrical power from the battery unit arrangement (610) to propel the electrical vehicle (100), and a vehicle cabin (150) including a seat arrangement (160) for accommodating one or more users of the electrical vehicle (100), characterized in that:

(i) the battery unit arrangement (610) is operable to be accommodated in at least a floor region of the electrical vehicle (100) beneath the vehicle cabin (150); and

(ii) the electrical vehicle (100) includes an engagement mechanism (400) for retaining the battery unit arrangement (610) onto the vehicle chassis, wherein the engagement mechanism (400) is releasable for repairing or replacing the battery unit arrangement (610), and the engagement mechanism (400) includes an emergency release element (170) for automatically releasing the battery unit arrangement (610) in an event of the electrical vehicle (100) experiencing a collision.

11. A battery unit arrangement (610) of claim 10, characterized in that the emergency release element (170) is operable to be triggered by a structural element (430) of a region of the vehicle chassis, the structural element being designed to undergo a submarining trajectory (Α-Α') in the event of the electrical vehicle (100) experiencing a collision.

12. A battery unit arrangement (610) of claim 11, characterized in that the engagement mechanism (400) includes an emergency release element (170) that is operable to be triggered by a structural element (430) of a frontal region of the vehicle chassis for automatically releasing the battery unit arrangement (130) in an event of the electrical vehicle (100) experiencing a frontal collision.

13. A battery unit arrangement (610) of claim 11 or claim 12, characterized in that the engagement mechanism (400) includes an emergency release element (170) that is operable to be triggered by a structural element (430) of a rear region of the vehicle chassis for automatically releasing the battery unit arrangement (130) in an event of the electrical vehicle (100) experiencing a collision from the rear.

14. A battery unit arrangement (610) of claim 10, characterized in that the battery unit arrangement (610) comprises separable battery sub-units (1010) that are configured to accommodate battery modules, wherein each battery sub-unit (1010) comprises an access panel (1020).

15. A battery unit arrangement (610) of claim 10, characterized in that the engagement mechanism (400) is operatively coupled to a sensor arrangement (910) that is capable of sensing the event of the electrical vehicle (100) experiencing the collision.

16. A battery unit arrangement (610) of claim 15, characterized in that the sensor arrangement (910) includes a crash sensor.

17. A battery unit arrangement (610) claim 16, characterized in that the sensor arrangement (910) is operatively coupled to a controller (920), wherein the controller (920) is operable to instruct the emergency release element (630) to release the battery unit arrangement (610) based on a sensed signal from the sensor arrangement (910).

18. A battery unit arrangement (610) of any of the claims 10 to 17, characterized in that the emergency release element (630) comprises at least one of: an electromechanical arrangement, an electromagnetic arrangement.

19. A method of employing a battery unit arrangement (610) of claim 10, characterized in that the method includes:

(i) accommodating the battery unit arrangement (610) in at least a floor region of the electrical vehicle (100) beneath the vehicle cabin (150); and

(ii) employing an engagement mechanism (400) for retaining the battery unit arrangement (610) onto the chassis, wherein the engagement mechanism (400) is releasable for repairing or replacing the battery unit arrangement (610), and arranging for the engagement mechanism (400) to include an emergency release element (630) for automatically releasing the battery arrangement (610) in an event of the electrical vehicle experiencing (100) a collision.

20. A method of claim 19, characterized in that the method further includes:

(iii) receiving information pertaining to the electrical vehicle (100) experiencing the collision; and

(iv) releasing the battery unit arrangement (610) of the electrical vehicle (100) in the event of the electrical vehicle (100) experiencing the collision.

21. A software product recording on machine-readable data storage media, characterized in that the software product is executable upon computing hardware for implementing a method as claimed in claims 19 to 20.