WO2026013073A1 - Energy absorbing member with an open metal profile - Google Patents

Abstract

Energy absorbing member (1) comprising an open three-dimensional metal profile (2) and at least one layer of a three-dimensional part (3), being at least partially made from an organic material, the metal profile and the three-dimensional part are connected in a contact area (4) and the three-dimensional part comprises a sidewall (14), the sidewall has segments (6, 7) of different wall thickness; and a method to absorb energy during an impact using such an energy absorbing member.

Description

Energy absorbing member with an open metal profile

The present invention relates to an energy absorbing member, preferably comprising an optional open metal profile, and at least one layer of a three-dimensional organic part, being at least partially made from an organic material, the optional metal profile and the three- dimensional part can be connected in a contact area and the three-dimensional part comprises a sidewall. The present invention further relates to a method to absorb energy during an impact.

Energy absorbing members as described above are known from the state in the art and are utilized to reduce to reduce the consequences of an automotive collision and/or accident. There is a constant need to make these energy absorbing members mechanically more stable, lighter and/or more cost efficient.

It was therefore the problem of the present invention to provide an improved energy absorbing member and an improved method to absorb energy.

The problem is solved with an energy absorbing member, preferably comprising an optional open metal profile, and at least one layer of a three-dimensional organic part, being at least partially made from an organic material, the optional metal profile and the three-dimensional part can be connected in a contact area and the three-dimensional part comprises a sidewall, wherein the sidewall has segments of different wall thickness.

The disclosure made regarding this member subject matter also applies to the inventive method and vice versa. Features disclosed regarding this member can be included into the method and vice versa.

The present invention relates to an energy absorbing member that is utilized to improve the mechanical stability of a vehicle, especially an automotive vehicle, and further especially an automotive electric vehicle. Improvement in the mechanical stability of a vehicle is realized particularly during an impact caused by a collision or accident, for example, in a side impact. For an electrical vehicle (i.e. , a vehicle that uses one or more electric motors powered by a battery system), the Energy absorbing member and method preferably provides mechanical stability to protect the battery system in the event of, for example, a side impact, e.g., a type of collision as to which a vehicle collides with a relatively narrow, rigid object like a pole or tree at a sideways angle, and which is simulated using a well known pole side impact test, such as the European New Car Assessment Program (Euro NCAP) oblique pole side impact testing protocol (v. 7.2 (2023)).. The Energy absorbing member can be part of the body in white or can be added to the body in white. The Energy absorbing member preferably exhibits a mode of deformation that results in efficient energy absorption within a small contained volume that helps avoid intrusion into a battery system.

The inventive Energy absorbing member may comprise an open profile part, preferably a metal part, such as a steel part. Preferably, the profile part (e.g., the metal profile part) does not comprise a closed cavity. The organic material part is preferably not placed into a cavity of the profile part, but on a surface of the open profile part (e.g., its inner surface). Preferably, the open profile part is deep drawn, but can also be produced by extrusion, roll-forming or other transformation methods. Preferably, an open profile part e.g., a metal, particularly, a steel part with a certain grade is selected, wherein the highest grade at which the desired draw distance and thickness can still be achieved is preferred.

According to the present invention, the energy absorbing member also comprises a three- dimensional organic part, for instance, a part that is at least partially made from an organic material, preferably a composite material that includes a polymeric material; e.g., a thermoset and/or a thermoplastic. The three-dimensional organic part is preferably a moulded part; e.g., injection molded, compression molded, or otherwise. Preferably, this three-dimensional organic material part comprises a multitude of projections. Preferably, the three-dimensional organic layer part is provided as a layer.

Preferably, the energy absorbing member comprises more than one layer, preferably two layers which are stacked, wherein preferably one projection of one layer is stacked into a hollow portion; e.g., a hollow projection, of an adjacent layer. For example, one or more projections of one layer may nestingly be positioned into the hollow portion of the adjacent layer.

The three-dimensional part comprises a sidewall, wherein the sidewall preferably has segments of different wall thickness. Preferably the open profile part has a constant geometry along the energy absorbing member length, measured e.g. from a forward end to a rearward end of the profile and/or the three-dimensional part has a geometry that varies along the length of the reinforcement member.

Preferably, the organic material from which the three-dimensional part is made has a tensile modulus that is between 1000 - 3500 MPa, preferably 1500 - 2000, measured according to ISO 527 (Type 1A). The projections are preferably arranged in an array. The projections are preferably connected at their base, which can be in contact with the open metal part. Preferably, the base comprises an area that surrounds each projection at least partially, preferably entirely, for example, to provide a relatively large contact area between the three-dimensional part and the open metal part. Two adjacent projections can additionally or alternatively be connected via a bridge and/or a rib and/or a cavity. The projections are preferably hollow. The projections preferably have the shape of a truncated cone, preferably a hollow truncated cone, wherein the area of the cross section of the projection is reduced from the base to its top. The angle of inclination of the sidewall of the projection is preferably between >0° and 5°, preferably > 0,3 and 4° more preferably between 3 - 3,9°, measured relative to the centerline of the projection. The cross section of the projection need not be round but can also be oval or polygonal, preferably hexagonal or octagonal or a square or a rectangle.

Preferably, the projection is open at at least one of its longitudinal ends, preferably both longitudinal ends to save weight and/or to allow flow of a coating material, preferably e-coat. The opening of the projections at the top of two adjacent projections may be different. Preferably at one end, preferably at the base, the entire inner area of the projection is open. The length of a projection measured from the base to the top is preferably corresponding to the maximum available distance in the section of the vehicle structure where the part is introduced. The length of a projection measured from the base to the top is preferably between 120 and 170 mm, preferably 140 - 160 mm, more preferably between 145 - 155 mm.

The thickness of the base of the three-dimensional element is preferably between 1,5 and 6mm, more preferably 2,0 to 4,0 mm).

Preferably, adjacent projections do not touch at the base, but there is a distance between two adjacent projections.

In case two adjacent projections are connected by a bridge and/or a rib or a cavity, the cross section, square to the center axis of the extension, is preferably peanut-shaped. That is, it will have two end portions that are connected together by a thinner middle portion, such that the resulting shape is wider at both end portions and narrower in the middle, giving it a general appearance peanut shell cross-section. The two end portions preferably each have an oval cross section. The two end portions are preferably identical. Each projection comprises a sidewall. According to the present invention, the thickness of this sidewall need not be constant, and preferably is not constant, but comprises at least two sections with different sidewall thicknesses. Preferably, the sections are stacked upon each other relative to the longitudinal extension of the projection and more preferably in the respective section, the sidewall thickness is at least essentially constant. Preferably, two adjacent sections with different sidewall thickness are connected by a shoulder. Preferably, the shoulder is at 20 - 80%, preferably 40 - 70%, more preferably 45 - 55 % of the total height of the projection.

Preferably, the longitudinal extension of at least one projection of the three-dimensional part is not constant around its entire circumference.

The three-dimensional part is connected to the open metal profile at a contact area. Preferably, this contact area is larger than the area resulting from the wall thickness at a base. Preferably, the contact area is a flange that extends around each projection.

Preferably, the contact area between the three-dimensional organic material part and the metal profile part extends over at least two different levels. In case the metal part has a groove, or a notch, the three-dimensional part preferably contacts the metal part at the groove/notch and/or at the level above the groove/notch. In this case the longitudinal extension of at least one projection of the three-dimensional part is preferably larger in the area of the overlap with the groove/notch than at the area where the projection does not overlap with a groove/notch.

According to a preferred embodiment of the present invention, the three-dimensional part comprises a multitude of projections, preferably provided as an array. Preferably, a plurality of more preferably all, extensions of one three-dimensional element have essentially the same shape.

Preferably, the energy absorbing member comprises one, two, three four or more layer(s) of three-dimensional parts. In case of two or more layers, the layers are preferably stacked. Preferably the projection of one layer is inserted into the projection of the adjacent layer. The layers can be made of the same material or the respective layers can be made from a different material, i.e. , a different material being one that is different in composition, and/or a material that is similar in composition but has a different microstructure and/or different material properties. However, the same material for all layers of one three-dimensional part is preferred. Two adjacent layers are preferably connected, preferably by material connection for example adhesion, or heat staking and/or mechanically joined elements. In case of two or more stacked layers, the segments of larger wall thickness of one layer of the three-dimensional part are adjacent to segments of smaller wall thickness of the neighboring layer of the three-dimensional part. Preferably, there is a distance between the bases of two stacked layers.

Preferably two layers of three-dimensional parts are initially 5 - 50 mm apart.

The problem is also solved with a method to absorb energy during an impact (8) with an energy absorbing member according to the previous description, comprising the following steps: a. Select a metal material for the metal profile (2) and design (and optionally fabricate) the profile. Preferably it is designed so that the profile is tuned to respond to a predefined moment of inertia, while respecting the process- and material-related dimensional restrictions (bend-angle, drawing distance, thickness) of the metal material. b. Design (and optionally fabricate) a three-dimensional part (3). c. Combine the metal profile (2) and the three-dimensional part (3) to a vehicle. d. Load the metal profile (2) and the three-dimensional part (3) with impact energy (8) wherein the three-dimensional part (3) absorbs 75 - 95% of the energy absorbed. e. Crush the segment (6) of the three-dimensional part (3) with the lower wall thickness. f. Continue to load the metal profile (2) and the partially crushed three-dimensional part (3) with impact energy, wherein the three-dimensional part (3) absorbs 75 - 95% of the energy absorbed. g. Crush the segment (7) of the three-dimensional part (3) with the high wall thickness. h. Compress the metal profile (2) and the Energy absorbing member(1) until full deformation.

The method can be performed by building and testing an actual vehicle, in which case fabricating the parts is done. The method can be performed by computer aided design (e.g., using finite element analysis modeling) simulating a vehicle structure in an impact scenario.

The disclosure made regarding this subject matter also applies to the inventive energy absorbing member and vice versa. Features disclosed regarding this method can be included into the Energy absorbing member and vice versa.

Due to the inventive method, energy absorption of the three-dimensional part and the stiffness of the metal part are optimized and the optimal balance between the quantity of organic- and metal material is achieved. The inventive method avoids a premature deformation of the metal profile. The three-dimensional part deforms prior to deformation, particularly plastic deformation, of the metal profile.

In case, the three-dimensional part comprises one single layer and the energy absorbed according to step d. is preferably 80-90% and/or the energy absorbed according to step f. is preferably 75 - 85%.

In case, the three-dimensional part comprises exactly two layers and the energy absorbed according to step d. is preferably 85-95% and/or the energy absorbed according to step f. is preferably 85 - 99%.

Preferably, during an impact, the areas with the lower wall thickness of the projections collapse prior to the areas with a larger wall thickness.

The problem is also solved with a method to absorb energy during an impact utilizing the inventive reinforcement member, wherein at least one projection is crushed and one is deformed sideways (e.g., it deflects laterally away the direction of impact).

The disclosure made regarding this subject matter also applies to the inventive energy absorbing member and vice versa. Features disclosed regarding this method can be included into the Energy absorbing member and vice versa.

During crushing, the longitudinal extension of the projection is reduced, preferably significantly reduced, for example more than 30%, more preferably more than 40% or even more preferably more than 50% of its original extent. The longitudinal extension of the projection that is deformed sideways deforms to a lower degree than the extent of crushing, and is at best only slightly reduced, preferably < 20 %, more preferably < 10%.

The energy absorbing member herein may be used in an electric vehicle in which the energy absorbing member is located adjacent a container of a battery system, preferably in a rocker of the vehicle.

The inventions are now explained according to the Figures. These explanations do not limit the scope of protection and apply to both subject matters likewise.

Figures 1a - 1d show an embodiment with a three-dimensional part with one single layer.

Figures 2a 2d show an embodiment with a three-dimensional part with one single layer. Figure 3a - 3d show an embodiment with two different 3D-distances.

Figure 4a, b shows a peanut-shaped cross section of two adjacent projections.

Figure. 5 shows the angle of inclination of the projection.

Figure 6 shows the sideward deformation of projections relative to the direction of impact.

Figure 1a shows the inventive Energy absorbing memberl which comprises an open metal profile 2. Contrary to the state in the art, the metal profile is open; i.e. there is no closed cavity with a significant production and assembly advantage. The metal profile is preferably a steel profile that is more preferably deep drawn or extruded or roll-formed. The grade of the steel is preferably chosen as high as possible, wherein the grade is limited by the draw distance, bending angle and thickness. The Energy absorbing memberl further comprises a three-dimensional part 3, which is at least partially, preferably entirely made from an organic material, preferably a composite material. The three-dimensional part is preferably injection- moulded. This three-dimensional part 3 comprises a plurality of projections 15, which are in the present case each shaped as truncated cone. The longitudinal extension of the projections is indicated with the reference sign “L” in Fig. 1a. The projections 15 are hollow and each projection is preferably open at its base, preferably the entire inner area of the base is open. Two adjacent projections are preferably connected at their base. The base and/or the top of the projection may comprise a hole to allow free flow of a coating material. Each cone has a sidewall 14, which is not constant over the entire longitudinal extension L of the projection. In the present case there are two sections 6 ,7 with different sidewall thicknesses, wherein the lower sidewall thickness is in the present case in a section adjacent to the metal profile 2, while the seton with the larger sidewall thickness is further away from the metal profile. In each section 6, 7 the sidewall thickness is at least essentially constant around the entire circumference of the projection. At the transition between the sections 6, 7 there is in the present case a shoulder. The metal profile 2 and the three-dimensional part 3 are connected in a contact area 4, for example by adhesion or mechanical means. This contact area 4 is preferably larger than the area resulting form the thickness 7 at the base of the projection. This results in a robust support of the three-dimensional part 3 at the metal profile 2.

Figure 1b depicts details of the open three-dimensional metal profile 2. As can be seen, the metal is open, because it does not comprise any cavity, particularly no cavity that embeds the three-dimensional part 3. In the present case the three-dimensional metal part 2 is deep drawn and in the present example comprises two grooves 11. Each groove 11 may extend over the entire length of the metal profile 3 (into and out of the paper plane) or may be provided only over a limited extension of the axial length of the metal profile. Since the metal profile 2 is 3D-shaped, it extends over two levels 12, 13, distant from each other by the 3D- distance H. In the present case, the 3D distance is the draw distance. It is also depicted, that the three-dimensional part 3 preferably extends into the grooves of the metal profile 2. This preferably results in a contact area 4 between the metal profile 2 and the three-dimensional part 3 which extends over two levels 12, 13. In the example according to Figure 1b, the section 6 with the lower sidewall thickness is directly adjacent to the metal profile 2.

Figures 1c - 1d show the Energy absorbing memberl in an impact situation, depicted by arrow 8. In Figure 1c a force-displacement diagram of the Energy absorbing memberl according to Figure 1b under an impact 8 is depicted. As can be seen, the force on the Energy absorbing memberl increases to a first peak level until the section 6 of the three- dimensional part 3 with the lower sidewall thickness crushes and the metal profile deforms under the load. This decreases the force on the Energy absorbing memberl and absorbs impact energy, the integral under the force-load curve (first shaded area “crushing”). The crushing of the section 6 and the deformation of the metal profile 2 is depicted in the left hand picture at the bottom of Figure 1c. Once the crushing of section 6 is finalized, the force increases again, until a second peak is reached at which the crushing of section 7 of the projections 15 starts as can be seen from the right hand picture of the bottom of Figure 1c. This decreases the force on the Energy absorbing memberl and absorbs impact energy, the integral under the force-load curve (second shaded area “crushing”). During and/or after the crushing of the section 7 with the higher sidewall thickness the metal profile is also deformed.

In Figure 1d, the energy uptake is depicted during the first and the second phase of the impact 8. It can be seen that in the first phase (crushing of section 6) the three-dimensional part 3 takes up 85% of the impact energy, while the metal profile receives only 15% of the energy. This is so relatively low that the metal profile 2 only deforms slightly. During the second phase, section 7 of the three-dimensional part 3 takes up 81% of the energy absorbed and the metal profile 19% but the force is so high that the metal profile 2 also deforms.

Figures 2a - 2d show a second embodiment of the present invention. Essentially reference can be made to the explanations according to Figure 1a - d, particularly Figures 1a and b. However, in the present example, the three-dimensional part 3 comprises two layers 9, 10. Layer 10 has already been described in Figures 1a and b. The second layer 9 is stacked upon layer 10 such that the projections 15 of layer 10 are inserted into the hollow sections of the projections formed in layer 9. Layer 9 is similar to layer 10, but in the sequence of the section 7 with the lower sidewall thickness and the section 6 with the higher sidewall thickness have been reversed. Consequently, the section 6 with a lower sidewall thickness of the projections 15 in layer 10 are directly adjacent to the section 7 with the higher sidewall thickness of the projections 15 of layer 9 and vice versa. As can be seen from Figure 2b, both layers 9, 10 extend into the groove 11 of the metal profile, even though there is preferably only a contact area 4 between layer 10 and the metal profile 2. The three- dimensional part 3 is also supported on the upper level of the metal profile. Figure 2c shows the first phase of an impact 8. After the force has reached a first peak the sections 6 of the projections 15 with the smaller thickness of the sidewall of both layers 9, 10 starts to crush.

The progressing impact situation is also depicted in Figure 2d. As can be seen, the force on the Energy absorbing memberl increases to a first peak level. Then, the section 6 of the three-dimensional part 3 with the lower sidewall thickness of both layers 9, 10 crushes under the load. Simultaneously, the metal profile deforms plastically, which finally decreases the force on the Energy absorbing memberl . The crushing and deformation absorbs impact energy, the integral under the force-load curve (first shaded area). The crushing of the section 6 and the deformation of the metal profile 2 is depicted in the left hand picture at the bottom of Figure 2d. Once the crushing of section 6 is finalized, the displacement continues while the force decreases, until the crushing of section 7 of both layers 9, 10 starts as can be seen from the right hand picture of the bottom of Figure 1c. This absorbs impact energy, the integral under the force-load curve (second shaded area “crushing”). During the crushing of the section 6 with the lower sidewall thickness the metal profile is also deformed and energy is absorbed as can be seen from the graph in Figure 2d. During the second crushing, the metal profile does not deform, at least not significantly, Therefore not or little energy is absorbed during this phase as can be seen from the graph in Figure 2d. The final state of the Energy absorbing memberl is depicted in the lower right hand picture of Figure 2d.

Figures 3a - 3d show the influence of certain design parameters on the deformation and energy absorption of the inventive Energy absorbing memberl. In the embodiment according to figures 3a and 3b, the 3D-distance H, here the draw distance, is relatively small resulting in a relatively shallow metal profile. In Figures 3c and 3d, the 3D-distance H, here the draw distance, is relatively high resulting in a relatively rigid metal profile.

The force displacement graph for metal profile with relatively little 3D-distance is depicted in Figure 3a. which is the graph already shown in Figure 2d, so that reference can be made to the above said. In Figure 3b the influence of a one- or two-layered three-dimensional part 3 on the energy absorption of a Energy absorbing member! with a relatively shallow metal profile is depicted. The two layered three-dimensional part 3 absorbs most of the energy, particularly during the second phase.

In the embodiment according to Figures 3c and 3d the metal profile 2 has a relatively large 3D-distance, particularly in comparison to the embodiment according to Figures 3a and b. This leads to a deformation of the metal profile 2 during the crushing of both sections 6, 7 and in between. Once a certain force level is reached this level is essentially maintained over the entire displacement.

Figure 3d shows that the number of layers has relatively little influence on distribution of the energy absorption.

Figures 4a and 4b shows an embodiment in which the cross section of two projections 15 which are connected by a rib or a bridge 16 have a peanut-shaped cross-section. Figure 4a depicts the entire layer 9, while Figure 4b shows a cross section of this embodiment as indicates in Fig. 4a. As can be seen from Fig. 4b, the cross section of two adjacent projections 15 and the rib/bridge 16 is peanut-shaped. The person skilled in the art understands, that Fig. 4b is only a schematic drawing depicting only the circumference of the projections plus the rib/bridge. The projections are preferably hollow with a circular or hexagonal inner circumference.

Figure 5 depicts the angle of inclination a of the outer circumference of a projection 15. This angle is preferably constant over the entire circumference of the projection and/or over its entire height preferably except in the region of the shoulder 19.

Fig. 6 depicts an impact situation. While the projections in the center of the impact (here two) are mainly crushed, the projections adjacent to the center are mainly tilted sidewards. This distributes the impact over a larger area, and improves the energy absorption.

The method herein contemplates designing and/or fabricating a structure as described in each of the drawings of the member herein before an impact is depicted (e.g., Figs. 1a, 1b, 2a, 2b, 4a, 5). The method herein contemplates loading a Energy absorbing member as described in a manner such that the crush response is realized as described in any of Figs. 1d, 1d, 2c, 2d, and 6. The skilled person will recognize from the description herein and the following claims that it is possible to realize a mode of deformation that results in efficient energy absorption within a small contained volume. This is particularly attractive in an electric vehicle in which it is desired to reduce the likelihood of intrusion into a battery system from a side impact (e.g., a pole side impact). It is thus recognized that the Energy absorbing member herein may be used in an electric vehicle in which the Energy absorbing member is located adjacent a container of a battery system, preferably in a rocker of the vehicle.

List of reference signs:

1 reinforcement member

2 metal profile, steel profile

3 three-dimensional part, composite part

4 contact area

5 recess, hole

6 lower wall thickness

7 higher wall thickness

8 impact

9 first layer

10 second layer

11 groove

12 first level

13 second level

14 sidewall

15 projections

16 rib, bridge

17 top of the projection

18 recess at the top of the projection

19 shoulder H 3D distance, draw distance L longitudinal extension a angle of inclination

Claims

Claims:

1. Energy absorbing member (1), preferably comprising an optional open metal profile (2), and at least one layer (9, 10) of a three-dimensional organic part (3), being at least partially made from an organic material, the optional metal profile (2) and the three-dimensional part (3) can be connected in a contact area (4) and the three- dimensional part (3) comprises a sidewall (14), characterized in, that the sidewall has segments (6, 7) of different wall thickness.

2. Energy absorbing member (1) according to claim 1, characterized in, that the contact area (4) is larger than the area resulting from the wall thickness (6, 7) at a base.

3. Energy absorbing member (1) according to one of the preceding claims, characterized in, that the contact area (4) extends over at least two different levels (12, 13).

4. Energy absorbing member (1) according to one of the preceding claims, characterized in, that the three-dimensional part (3) comprises a multitude of projections (15), preferably provided as an array.

5. Energy absorbing member (1) according to one of the preceding claims, characterized in, that two adjacent projections (15) are connected by a rib (16).

6. Energy absorbing member (1) according to claim 5, characterized in, that a cross section of two rib-connected adjacent and projections parallel to the contact area (4) is peanut-shaped.

7. Energy absorbing member (1) according to one of the preceding claims, characterized in, that the projection is taper from the contact area to its top (17).

8. Energy absorbing member (1) according to claim 7, characterized in, that the angle of inclination of the projection is between >0° and 5°, preferably > 0,3 and 4° more preferably between 3 - 3,9°.

9. Energy absorbing member (1) according to one of the preceding claims, characterized in, that the sidewall of the projection has a shoulder (19), that is preferably at 20 - 80%, preferably 40 - 70% of the total height of the projection.

10. Energy absorbing member(1) according to one of the preceding claims, characterized in, that the top of the projection comprises a recess (5).

11. Energy absorbing member(1) according to claim 10, characterized in, that the recesses (5) in two adjacent projections have a different size.

12. Energy absorbing member(1) according to one of the preceding claims, characterized in, that the tensile -us is between 1000 - 3500 MPa, preferably 1500 - 2000.

13. Energy absorbing member(1) according to one of the preceding claims, characterized in, that it comprises two layers (9, 10) of three-dimensional parts, which are preferably stacked, preferably heat staked.

14. Energy absorbing member(1) according to claim 5, characterized in, that segments (6) of larger wall thickness of the layer (9) of the three-dimensional part (3) are adjacent to segments (7) of smaller wall thickness of the neighboring layer (10) of the three-dimensional part (3).

15. Energy absorbing member(1) according to one of the preceding claims, characterized in, that the metal profile is a steel-profile and/or that the three-dimensional part (3) is made from a composite material that preferably includes a polymeric material.

16. Energy absorbing member(1) according to one of the preceding claims, characterized in, that the metal profile is formed, preferably roll-formed

17. Energy absorbing member(1) according to claim 8, characterized in, that the 3D- extension (H) is 5 - 50 mm.

18. Method to absorb energy during an impact (8) with a Energy absorbing member according to one of the preceding claims, comprising the following steps: a. Select a metal material for the metal profile (2) and design a 3D-distance. b. Design a three-dimensional part (3). c. Combine the metal profile (2) and the three-dimensional part (3) to a vehicle. d. Load the metal profile (2) and the three-dimensional part (3) with impact energy (8) wherein the three-dimensional part (3) absorbs 75 - 95% of the energy absorbed. e. Crush the segment (6) of the three-dimensional part (3) with the lower wall thickness. f. Continue to load the metal profile (2) and the partially crushed three-dimensional part (3) with impact energy, wherein the three-dimensional part (3) absorbs 75 - 95% of the energy absorbed. g. Crush the segment (7) of the three-dimensional part (3) with the high wall thickness. h. Compress the metal profile (2) and the Energy absorbing member (1) until full deformation.

19. Method according to claim 10, wherein the three-dimensional part comprises one single layer and the energy absorbed according to step d. is 80-90% and/or the energy absorbed according to step f. is 75 - 85%.

20. Method according to claim 10, wherein the three-dimensional part comprises exactly two layers and the energy absorbed according to step d. is 85-95% and/or the energy absorbed according to step f. is 85 - 99%.

21. Method according to claim 19, characterized in, that the areas with the lower wall thickness (6) of the projections collapse prior to the areas with a larger wall thickness (5).

22. Method to absorb energy during an impact (8) with a Energy absorbing member (1) according to one of the preceding claims, characterized in, that at least one projection is crushed and one is deformed sideways.

23. Use in an electric vehicle of a Energy absorbing member (1) as in any of claims 1 through 17, in which the Energy absorbing member is located adjacent a container of a battery system, preferably in a rocker of the vehicle.