Vehicle with a high-voltage battery

Abstract

Vehicle with a high-voltage battery (1) installed in a floor structure of the vehicle, wherein, in the event of ground contact, a road-side interference contour acts directly or indirectly on the high-voltage battery (1), to which an underrun protection device (4) with a number of sensors (29, 31, 33) is assigned, with the aid of which, in the event of ground contact, the point of impact of the road-side interference contour can be localized and the ground contact force (F) acting on the underrun protection device (4) can be detected, wherein the sensors (29, 31, 33) are signal-connected to an evaluation unit (35) which detects possible damage to the high-voltage battery (1) on the basis of the detected impact location and the detected ground contact force (F), and wherein the underrun protection (4) is divided into at least a first zone (Z1; Z2, Z3), which is of increased relevance for battery safety due to a statistical or empirical evaluation in the event of ground contact, and into a second zone (Z2, Z3; Z1), which, in contrast, is of reduced relevance for battery safety, characterized in that that the first zone (Z1; Z2, Z3) with increased safety relevance is assigned a sensor (29; 31, 33) with increased sensitivity, and that the second zone (Z2, Z3; Z1) with reduced safety relevance is assigned a sensor (31; 29) with reduced sensitivity, and that each of the sensors used in the underrun protection (4) is a pressure sensor (29, 31, 33) which has a pressure-tight sealed sensor hollow chamber (17, 19, 21) formed in the underrun protection (4), and that when the sensor touches the ground, the hollow sensor chamber (17, 19, 21) deforms, specifically under pressure change in the hollow sensor chamber (17, 19, 21), and that the pressure sensor (29, 31, 33) detects the pressure change and transmits a correlating pressure signal (S1, S2, S3) to the evaluation unit (35) of the control unit (32), and that both the pressure sensors (29, 31, 33) and the evaluation unit (35) are integrated in a control unit (32), and that at least, in particular exactly three sensor hollow chambers (17, 19, 21) are installed in the underrun protection, so that the control unit (32) has a corresponding number of signal connections (37) to the sensor hollow chambers (17, 19, 21), and that the underrun protection (4) is divided into a vehicle front zone (Z1) with reduced safety relevance, a vehicle middle zone (Z2) with increased safety relevance and a vehicle rear zone (Z3) with reduced safety relevance, and that two small-volume sensor hollow chambers (19, 21) of the highly sensitive pressure sensors (31, 33) are arranged in the central zone (Z2), and that exactly one low-sensitivity pressure sensor (29) with a large-volume sensor hollow chamber (17) is assigned to the vehicle front zone (Z1) and the vehicle rear zone (Z3), and that the volume-large sensor hollow chamber (17) of the low-sensitivity pressure sensor (29) is divided into a sub-chamber (39) which is installed in the vehicle front zone (Z1) and into a sub-chamber (41) which is installed in the vehicle rear zone (Z3), and that the two sub-chambers (39, 41) are fluidically connected to one another.

Description

[0001] The invention relates to an electrically powered vehicle with a high-voltage battery according to the preamble of claim 1.

[0002] In an example of an electrically powered, two-track vehicle, a high-voltage battery can be inserted from underneath the vehicle into a battery mounting space that is open at the floor. The battery mounting space can be delimited in the vertical direction of the vehicle by a vehicle floor that defines the vehicle interior, and in the transverse direction of the vehicle by side sills. In addition, the high-voltage battery can be covered by an underride guard at the floor. In the event of a ground contact, an interfering contour on the roadway, such as a bollard or curb, acts on the underride guard of the high-voltage battery with a ground contact force directed upwards. This deforms the underride guard, and the ground contact force can be transmitted via a load path to the high-voltage battery. Depending on the magnitude of the ground contact force, this can result in damage to the high-voltage battery.

[0003] A structural component is known from DE 20 2020 102 252 U1. A rail vehicle with ballast detection is known from EP 1 867 545 A1. DE 10 2018 129 158 A1 discloses a vehicle of this type. DE 10 2013 001 325 A1 discloses a method for operating a vehicle component of a vehicle by means of a control device depending on a safety state of the vehicle that can be evaluated at predeterminable times. Furthermore, DE 10 2013 001 325 A1 relates to a control device for implementing the method and to a safety system with such a control device.

[0004] The object of the invention is to provide a vehicle with a high-voltage battery in which possible battery damage due to impact with the ground can be easily detected.

[0005] The object is solved by the features of claim 1. Preferred developments of the invention are disclosed in the subclaims.

[0006] The invention is based on an underrun protection device that has a number of sensors that can be used to locate the point of impact of the ground contact and to measure the ground contact force acting on the underrun protection device. The sensors installed in the underrun protection device are connected to an electronic evaluation unit that detects potential damage to the high-voltage battery based on the detected impact point and the detected ground contact force.

[0007] According to claim 1, the underrun protection is divided into at least a first zone and a second zone during vehicle design. These zones are defined based on a statistical or empirical evaluation: The first zone is of increased relevance for battery safety in the event of impact, e.g., because there is a high probability of impact from road-side interference contours. In contrast, the second zone is of only reduced relevance for battery safety. For example, it has been statistically determined that the second zone of the underrun protection has only a reduced probability of impact from road-side interference contours.

[0008] According to the invention, a sensor with increased sensitivity is assigned to the first zone with increased safety relevance. In contrast, a sensor with correspondingly reduced sensitivity is assigned to the second zone with reduced safety relevance. In this way, the cost and manufacturing effort for sensor installation in the underrun protection zone with high safety relevance can be purposefully increased to ensure flawless sensing of all relevant ground contact load cases. In contrast, the cost and manufacturing effort for sensor installation in the zone with reduced safety relevance can be purposefully limited without compromising functionality, so that only ground contact load cases with correspondingly high ground contact force can be detected in the underrun protection zone with reduced safety relevance.

[0009] According to the invention, each of the sensors installed in the underrun protection is implemented as a pressure sensor with a pressure-tight hollow sensor chamber formed in the underrun protection. When the vehicle touches the ground, the hollow sensor chamber deforms. This results in a pressure change in the hollow sensor chamber. Based on the pressure change, the pressure sensor transmits a correlating pressure signal to the evaluation unit of a control unit.

[0010] The sensitivity of such a pressure sensor depends on the volume size of its sensor cavity. For example, a pressure sensor with a large sensor cavity exhibits reduced sensitivity, while a pressure sensor with a small sensor cavity exhibits increased sensitivity.

[0011] When used in the underrun protection system according to the invention, the highly sensitive pressure sensor can be designed to fully detect all relevant ground contact load cases. In contrast, a low-sensitivity pressure sensor installed in the underrun protection system can be designed to only detect limited ground contact load cases with correspondingly high ground contact force.

[0012] According to the invention, the control unit is composed, among other things, of the electronic evaluation unit and the pressure sensors. A conventional control unit typically has exactly three pressure sensors. The control unit can therefore have a total of three signal inputs or slots to which hose lines leading to the respective sensor cavities can be connected.

[0013] In a first embodiment, the underrun protection is divided into a front zone with increased safety relevance, a middle zone with reduced safety relevance, and a rear zone with increased safety relevance. In this case, a highly sensitive pressure sensor with a small-volume sensor cavity is assigned to the front zone and the rear zone. The middle zone, in contrast, is assigned a low-sensitivity pressure sensor with a large-volume sensor cavity.

[0014] According to the invention, the underrun protection is divided into a front zone of reduced safety relevance, a middle zone of increased safety relevance, and a rear zone of reduced safety relevance. In this case, two highly sensitive pressure sensors with small-volume sensor hollow chambers are assigned to the middle zone. In contrast, exactly one low-sensitivity pressure sensor with a large-volume sensor hollow chamber is assigned to the front zone and the rear zone. According to the invention, the large-volume sensor hollow chamber of the low-sensitivity pressure sensor is divided into two subchambers. One subchamber is installed in the front zone of the vehicle, while the other subchamber is installed in the rear zone of the vehicle. The two subchambers are fluidically connected to each other.

[0015] The invention provides a sensing concept for a high-voltage battery that allows conclusions to be drawn as to whether the battery cells of the high-voltage battery have experienced an intrusion by detecting the deformation of the underrun protection. Due to the limited number of connections in the control unit, only a very limited number of sensors can be used. Against this background, the invention divides the underrun protection into different zones, depending on their relevance and statistical hit locations. Sensors with different sensing sensitivities are assigned to each of these zones.

[0016] Embodiments of the invention are described below with reference to the attached figures.

[0017] They show: Fig. 1 a view from below of a vehicle floor; Fig. 2 an enlarged sectional view of the high-voltage battery installed in the vehicle with the associated underrun protection; Fig. 3 and Fig. 4 shows a schematic representation illustrating the division of the underrun protection into different zones.

[0018] In the Fig. 1 or Fig. 2, a high-voltage battery 1 is installed in a body floor structure of the vehicle. The high-voltage battery 1 is equipped with cell modules, of which Fig. 2 a cell module 2 is indicated, which is placed on a housing base 3 of the high-voltage battery 1. The housing base 3 of the high-voltage battery 1 is in the Fig. 2 is double-walled with an inner base 5 and an outer base 7, between which coolant channels 9 of a cooling system are formed. An underrun protection 4 is arranged on the underside of the housing base 3. This has a vehicle-lower underrun protection plate 13, which is arranged on the housing base 3 with an energy-absorbing material 15 interposed therebetween.

[0019] Between the underrun protection plate 13 and the housing base 3 there are a total of three sensor hollow chambers 17, 19, 21 ( Fig. 3), which are arranged one behind the other in the vehicle's longitudinal direction x. The sensor hollow chambers 17, 19, 21, together with pressure sensors 29, 31, 33, are components of a pressure sensor unit 23. Each of the sensor hollow chambers 17, 19, 21 is delimited to the outside by a circumferential sealing element 25. The circumferential sealing element 25 is in the Fig. 2 is supported between the battery housing base 3 and the underrun protection plate 13 and seals the sensor hollow chamber 17 shown against the energy-absorbing material 15. In the same way, the Fig. 2 not shown sensor hollow chambers 19, 21 sealed.

[0020] In the Fig. 3, the course of the sealing elements 25 around the respective sensor hollow chamber 17, 19, 21 is indicated. Each of the sensor hollow chambers 17, 19, 21 is connected to a pressure sensor 29, 31, 33 via a hose line 27. In the event of contact with the ground, a contact force F ( Fig. 2) impacts the underride protection 4, causing one or more sensor hollow chambers 17, 19, 21 to deform. This leads to a pressure change in the respective sensor hollow chamber, which is detected by the associated pressure sensor 29, 31, 33. Based on the pressure change, the pressure sensor generates a correlating pressure signal S1, S2, S3, which is sent to an evaluation unit 35 of a control unit 32. Based on the magnitude of the respective pressure signal S1, S2, S3, the evaluation unit 35 can draw conclusions about possible damage to the high-voltage battery 1.

[0021] In the Fig. 3, the three pressure sensors 29, 31, 33 are integrated into the control unit 32 together with the evaluation unit 35. The hose lines 27 leading from the sensor hollow chambers 17, 19, 21 are each connected to the signal inputs 37 or slots of the control unit 32.

[0022] As from the Fig. As can be seen further in Figure 3, the underrun protection 4 is divided into a front zone Z1, a middle zone Z2 and a rear zone Z3. Both the front zone Z1 and the rear zone 3 are in the Fig. 3 is of increased relevance for battery safety according to a design specification (based on a statistical or empirical evaluation of ground contact cases). In contrast, the middle zone Z2 is of only reduced relevance for battery safety according to statistical or empirical evaluation in ground contact cases. According to the invention, therefore, Fig. 3 a highly sensitive pressure sensor 29, 33 with a small volume sensor hollow chamber 17, 21 is assigned to the front zone Z1 and the rear zone Z3, while a low-sensitivity pressure sensor 31 with a large volume sensor hollow chamber 19 is assigned to the middle zone Z2.

[0023] The small-volume sensor hollow chambers 17, 21 of the highly sensitive pressure sensors 29, 33 are designed to fully detect all relevant ground contact load cases. In contrast, the large-volume sensor hollow chamber 19 of the low-sensitivity pressure sensor 31 is designed to only detect limited ground contact load cases that occur with a correspondingly high ground contact force F.

[0024] In the Fig. Figure 4 shows an alternative embodiment in which, according to the design specification, the vehicle's front zone Z1 and the vehicle's rear zone Z3 each have reduced safety relevance, while the vehicle's center zone Z2 has increased safety relevance. In this case, two small-volume sensor hollow chambers 19, 21 of the pressure sensors 31, 33 are arranged in the center zone Z2. In contrast, the vehicle's front zone Z1 and the vehicle's rear zone Z3 are assigned exactly one low-sensitivity pressure sensor 29 with a large-volume sensor hollow chamber 17.

[0025] As from the Fig. As further shown in Figure 4, the large-volume sensor hollow chamber 17 of the pressure sensor 29 is divided into two subchambers 39, 41. The first subchamber 39 is installed in the vehicle's front zone Z1, while the second subchamber 41 is installed in the vehicle's rear zone Z3. The two subchambers 39, 41 are fluidically connected to each other via side channels 43. LIST OF REFERENCE SYMBOLS: 1 high-voltage battery 2 battery module 3 Case back 4 Underrun protection 5 Interior floor 7 Exterior floor 9 coolant channels 13 Underrun protection plate 15 energy-absorbing material 17, 19, 21 Sensor hollow chambers 23 Pressure sensor unit 25 circumferential sealing element 27 hose lines 29, 31, 33 pressure sensors 35 Evaluation unit 32 Control unit 37 signal inputs 39, 41 subchambers 43 side channels Z1 to Z3 zones

Claims

[1] Vehicle with a high-voltage battery (1) installed in a floor structure of the vehicle, wherein, in the event of ground contact, a road-side interference contour acts directly or indirectly on the high-voltage battery (1), to which an underrun protection device (4) with a number of sensors (29, 31, 33) is assigned, with the aid of which, in the event of ground contact, the point of impact of the road-side interference contour can be localized and the ground contact force (F) acting on the underrun protection device (4) can be detected, wherein the sensors (29, 31, 33) are signal-connected to an evaluation unit (35) which detects possible damage to the high-voltage battery (1) on the basis of the detected impact location and the detected ground contact force (F), and wherein the underrun protection (4) is divided into at least a first zone (Z1; Z2, Z3), which is of increased relevance for battery safety due to a statistical or empirical evaluation in the event of ground contact, and into a second zone (Z2, Z3; Z1), which, in contrast, is of reduced relevance for battery safety, characterized by , that the first zone (Z1; Z2, Z3) with increased safety relevance is assigned a sensor (29; 31, 33) with increased sensitivity, and that the second zone (Z2, Z3; Z1) with reduced safety relevance is assigned a sensor (31; 29) with reduced sensitivity, and that each of the sensors used in the underrun protection (4) is a pressure sensor (29, 31, 33) which has a pressure-tight sealed sensor hollow chamber (17, 19, 21) formed in the underrun protection (4), and that when the sensor touches the ground, the hollow sensor chamber (17, 19, 21) deforms, specifically under pressure change in the hollow sensor chamber (17, 19, 21), and that the pressure sensor (29, 31, 33) detects the pressure change and transmits a correlating pressure signal (S1, S2, S3) to the evaluation unit (35) of the control unit (32), and that both the pressure sensors (29, 31, 33) and the evaluation unit (35) are integrated in a control unit (32), and that at least, in particular exactly three sensor hollow chambers (17, 19, 21) are installed in the underrun protection, so that the control unit (32) has a corresponding number of signal connections (37) to the sensor hollow chambers (17, 19, 21), and that the underrun protection (4) is divided into a vehicle front zone (Z1) with reduced safety relevance, a vehicle middle zone (Z2) with increased safety relevance and a vehicle rear zone (Z3) with reduced safety relevance, and that two small-volume sensor hollow chambers (19, 21) of the highly sensitive pressure sensors (31, 33) are arranged in the central zone (Z2), and that exactly one low-sensitivity pressure sensor (29) with a large-volume sensor hollow chamber (17) is assigned to the vehicle front zone (Z1) and the vehicle rear zone (Z3), and that the volume-large sensor hollow chamber (17) of the low-sensitivity pressure sensor (29) is divided into a sub-chamber (39) which is installed in the vehicle front zone (Z1) and into a sub-chamber (41) which is installed in the vehicle rear zone (Z3), and that the two sub-chambers (39, 41) are fluidically connected to one another. [2] Vehicle according to claim 1, characterized bythat the sensitivity of the pressure sensor (29, 31, 33) depends on the volume size of its sensor hollow chamber (17, 19, 21), and that a pressure sensor (29) with a large-volume sensor hollow chamber (17) has a reduced sensitivity, and a pressure sensor (31) with a small-volume sensor hollow chamber (19) has an increased sensitivity. [3] Vehicle according to claim 2, characterized by that the high-sensitivity pressure sensor is designed in such a way that a complete sensing of all relevant ground contact load cases takes place, and that the low-sensitivity pressure sensor is designed in such a way that only a limited sensing of ground contact load cases can be carried out which occur with a correspondingly high ground contact force (F). [4] Vehicle according to one of the preceding claims, characterized bythat the underrun protection (4) is divided into a vehicle front zone (Z1) with increased safety relevance, a middle zone (Z2) with reduced safety relevance and a vehicle rear zone (Z3) with increased safety relevance, and that a highly sensitive pressure sensor (29, 33) with a small-volume sensor hollow chamber (17, 21) is assigned to the vehicle front zone (Z1) and the vehicle rear zone (Z3), while a low-sensitivity pressure sensor (31) with a large-volume sensor hollow chamber (19) is assigned to the middle zone (Z2).

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