Electrified vehicle

Abstract

To ensure a high level of safety when a battery is replaced in an electrified vehicle that can travel by power from an electric motor that exchanges electric power with the replaceable battery.SOLUTION: An electrified vehicle of the disclosure includes: at least one replaceable battery; an electric motor that exchanges electric power with the battery; a battery case; and a locking device. The battery case includes: a case body having an opening through which the battery is inserted and removed; and a lid that opens and closes the opening of the case body. The locking device locks the lid of the battery case in a non-openable manner when at least a start-up switch of the electrified vehicle is turned on.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an electric vehicle that can run on power from an electric motor that exchanges power with a replaceable battery. [Background technology]

[0002] A known straddle-type electric vehicle includes a battery storage compartment provided below a floor on which a passenger places their feet, with the battery stored in the battery storage compartment in a detachable manner (see, for example, Patent Document 1). A cover member for the battery storage compartment is integrated with the upper surface of the battery of this straddle-type electric vehicle so as to form the floor. A power supply connector and a striker are provided on the lower surface of the battery. The battery storage compartment also includes a power receiving connector to which the power supply connector is connected and a latch for securing the striker. Thus, by gripping the cover member and lowering the battery into the battery storage compartment, the power supply connector is connected to the power receiving connector and the striker is secured to the latch. By operating the main key to release the engagement between the striker and the latch, the cover member can be lifted to detach the power supply connector from the power receiving connector, allowing the battery to be removed together with the cover member. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-208962 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-described conventional saddle-type electric vehicles, the user can remove the battery by operating the main key to release the engagement between the striker and the latch. However, from the standpoint of safety, careless battery removal should not be permitted.

[0005] Therefore, a main object of the present disclosure is to ensure safety when replacing a battery in an electric vehicle that can run using power from an electric motor that exchanges power with a replaceable battery. [Means for solving the problem]

[0006] The electric vehicle disclosed herein includes at least one replaceable battery and an electric motor that exchanges power with the battery, and is capable of running using power from the electric motor. The electric vehicle also includes a battery case that includes a case body having an opening through which the battery is inserted and removed, and a lid that opens and closes the opening of the case body, and a locking device that locks the lid so that it cannot be opened, at least when the start switch of the electric vehicle is turned on.

[0007] In the electric vehicle of the present disclosure, the lid of the battery case that houses the replaceable battery is locked so that it cannot be opened at least when the start switch of the electric vehicle is on. This effectively prevents a worker attempting to replace the battery from touching the battery when a closed circuit including the battery is formed in the electric vehicle or when there is a possibility that such a closed circuit will be formed. As a result, the electric vehicle of the present disclosure can effectively ensure safety during battery replacement. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a schematic configuration diagram showing an electric vehicle according to the present disclosure. [Figure 2] FIG. 2 is a schematic configuration diagram showing a battery case included in the electric vehicle of the present disclosure. [Figure 3] FIG. 2 is a perspective view showing a locking device for a battery case included in an electric vehicle according to the present disclosure. [Figure 4] FIG. 2 is a control block diagram of the electric vehicle of the present disclosure. [Figure 5] 4 is a time chart for explaining a process for determining whether a battery relay is welded in an electric vehicle according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0009] Next, embodiments of the present disclosure will be described with reference to the drawings.

[0010] Fig. 1 is a schematic diagram showing an electric vehicle 100 of the present disclosure. The electric vehicle 100 shown in the figure is a battery electric vehicle (BEV) that includes a plurality of replaceable batteries 10, a system main relay SMR which is a normally open mechanical relay (contact relay), a power control unit (hereinafter referred to as "PCU") 110, and a motor generator MG. The PCU 110 includes an inverter (drive circuit) that drives the motor generator MG, a boost converter, a DC / DC converter, etc. The motor generator MG is a synchronous generator motor (three-phase AC motor).

[0011] The rotor of the motor generator MG is connected to a drive shaft that rotates integrally with the drive wheels (wheels) DW via a power transmission device that includes a reducer and a differential gear. The motor generator MG is driven by electric power from the PCU 110 (battery 10) and outputs drive torque (driving force) to the drive wheels DW. The motor generator MG also outputs regenerative braking torque to the drive wheels DW when braking the electric vehicle 100, and the electric power generated (regenerated) by the motor generator is stored in the multiple batteries 10.

[0012] In this embodiment, the electric vehicle 100 is a commercial vehicle used for delivering packages and the like. As the SOC decreases, the multiple batteries 10 mounted on the electric vehicle 100 are replaced with multiple fully charged batteries 10 that have been charged by an external battery charging device 80 (see FIG. 2) installed at a package collection and delivery center, a parking facility for the electric vehicle 100, or the like. At the collection and delivery center or the like, the multiple batteries 10 are taken in and out of the electric vehicle 100 and the battery charging device 80 using a battery transport cart 90 (see FIG. 2).

[0013] The multiple batteries 10 each include a substantially rectangular parallelepiped pack case and multiple battery cells 11 housed in the pack case, and have the same specifications (including dimensions). The battery cells 11 of each battery 10 are, for example, lithium-ion secondary battery cells or nickel-metal hydride secondary battery cells. In this embodiment, the multiple battery cells 11 are connected in series within the pack case to form a cell stack. The positive terminal of the cell stack is electrically connected to a positive connector 12p via a mechanical (contact type) battery relay Rp, and the negative terminal of the cell stack is electrically connected to a negative connector 12n via a mechanical battery relay Rn.

[0014] As shown in FIG. 1, an electric vehicle 100 includes a battery case 1 that houses a plurality of (for example, three in this embodiment) replaceable batteries 10 arranged in parallel. The battery case 1 is fixed to a floor panel (vehicle body) of the electric vehicle 100 via a plurality of brackets B (see FIG. 2) so as to be located, for example, behind the front seats of the electric vehicle 100, and defines a battery storage section of the electric vehicle 100. The battery case 1 includes a case body 2 that is a rectangular cylindrical body with a bottom and has an opening 2o, and a lid 3 that opens and closes the opening 2o of the case body 2. In this embodiment, the case body 2 of the battery case 1 is fixed to the floor panel so that the opening 2o faces, for example, the side of the driver's seat of the electric vehicle 100.

[0015] A plurality of positive receptacles 4p, each capable of coupling with a positive connector 12p of a corresponding battery 10, and a plurality of negative receptacles 4n, each capable of coupling with a negative connector 12n of a corresponding battery 10, are disposed inside the case body 2 of the battery case 1. The plurality of batteries 10 are connected in series via two pairs of electrically connected positive and negative receptacles 4p and 4n. The positive receptacles 4p not connected to the negative receptacles 4n are electrically connected to the positive power line PL via a positive relay of the system main relay SMR, and the negative receptacles 4n not connected to the positive receptacle 4p are electrically connected to the negative power line NL via a negative relay of the system main relay SMR. The positive power line PL and the negative power line NL are electrically connected to the PCU 110. When the system main relay SMR is closed, the PCU 110 becomes electrically connectable to the plurality of batteries 10. Furthermore, voltage sensors V1, V2, and V3 are installed near the battery case 1 on the floor panel of the electric vehicle 100 or on the battery case 1, and detect the voltage between a positive electrode receptacle 4p and a negative electrode receptacle 4n arranged in the back case of each corresponding battery 10.

[0016] As shown in FIG. 2 , the case body 2 of the battery case 1 is formed, for example, from multiple pressed metal plates. It includes a bottom 20, a pair of side walls 21 each extending upward from a corresponding side edge of the bottom 20, a ceiling 22 spaced apart from the bottom 20, and an end wall 23. The bottom 20, the pair of side walls 21, and the ceiling 22 form a flat rectangular tube, and the end wall 23 closes one end of the rectangular tube. This defines a rectangular opening 2o at the end of the case body 2 opposite the end wall 23. The positive electrode receptacles 4p and the negative electrode receptacles 4n are each disposed adjacent to the end wall 23. The bottom 20 and the pair of side walls 21 of the case body 2 may be integrally formed, or they may be formed separately and fixed to each other.

[0017] A plurality of (three) batteries 10 are housed inside the case body 2, lined up along the longitudinal direction (width direction) of an opening 2o serving as an insertion port. That is, each battery 10 is inserted into or removed from the case body 2 through the opening 2o in the extension direction of the pair of side wall portions 21. A plurality of partition walls 24 (see FIG. 1) are also arranged inside the case body 2 so as to be positioned between adjacent batteries 10. Furthermore, the case body 2 is provided with a plurality of (for example, three in this embodiment) case-side guide portions 25 having the same height and width so that the batteries 10 can be easily positioned in the battery case 1 and housed therein.

[0018] As shown in FIG. 2 , the multiple case side guide portions 25 extend parallel to the side wall portions 21 from the opening 2o toward the end wall portions 23 (inside the case main body 2) and are arranged on the bottom portion 20 so as to be spaced apart in the longitudinal direction (width direction) of the opening 2o. In this embodiment, each case side guide portion 25 is formed by pressing from the inner surface (top surface) of the bottom portion 20, which serves as the inner bottom surface of the case main body 2, to protrude toward the interior of the case main body 2, i.e., toward the ceiling portion 22, and is located below the center in the width direction of each battery 10 housed in the case main body 2. The upper surface of each case side guide portion 25 is formed flat, and an inclined surface that connects the upper surface to the inner surface of the bottom portion 20 is formed at the end of each case side guide portion 25 on the opening 2o side and the end on the end wall portion 23 side.

[0019] The lid 3 is formed, for example, from a pressed metal plate, and is supported by the case body 2 via multiple hinges (not shown) so as to be rotatable about a rotation axis A (see FIG. 2). The rotation axis A extends along the lower edge of the opening 2o, i.e., along one side of the bottom 20 that defines the opening 2o. This allows the lid 3 to be opened and the opening 2o to be exposed by rotating the lid 3 from top to bottom about the rotation axis A (tilting it forward). In addition, the lid 3 can be closed and the opening 2o to be closed by rotating the lid 3 from bottom to top about the rotation axis A (flipping it up).

[0020] 2, the lid 3 is provided with a plurality of (for example, three in this embodiment) lid-side guide portions 35 having the same height and width so as to align with the corresponding case-side guide portions 25 when the lid 3 is open (fully open). The lid-side guide portions 35 are formed by press working so as to protrude from the inner surface of the lid 3 toward the interior of the case body 2 and to be aligned at intervals in the longitudinal direction (width direction) of the lid 3, and are located below the center in the width direction of each battery 10 to be inserted into or removed from the case body 2. The upper surface of each lid-side guide portion 35 is formed flat and is included in approximately the same plane as the upper surface of the corresponding case-side guide portion 25 when the lid 3 is open (fully open). Furthermore, an inclined surface 35a is formed at the end of each lid side guide portion 35 on the free end side of the lid body 3, connecting the upper surface of the lid side guide portion 35 to the inner surface of the lid body 3, and an inclined surface 35b is formed at the end of each lid side guide portion 35 on the rotation axis A side, connecting the upper surface of the lid side guide portion 35 to the inner surface of the lid body 3.

[0021] Each battery 10 includes a guided portion (not shown) that engages with the case-side guide portion 25 of the case body 2 and the lid-side guide portion 35 of the lid 3. In this embodiment, the guided portion is a pair of ridges (rails) that protrude downward from the bottom surface of the battery 10 (pack case) and extend in the longitudinal direction of the battery 10. The pair of ridges extend parallel to each other at a distance slightly larger than the width of the case-side guide portion 25 and the lid-side guide portion 35, and are in sliding contact with the corresponding side surfaces of the case-side guide portion 25 and the lid-side guide portion 35 and the inner surface of the bottom portion 20. At least one end surface of each battery 10 (pack case) is provided with an abutment member 15 (see FIG. 2 ) made of an elastic material such as rubber or resin. The abutment member 15 is located below the handle portion 14 of the battery 10 and has a surface that slopes away from the end surface of the battery 10 from the top surface to the bottom surface of the battery 10.

[0022] Additionally, the case body 2 of the battery case 1 is provided with a locking device 5 that locks the lid 3 that closes the opening 2o so that it cannot be opened, and two courtesy switches 6 that detect the opening and closing of the lid 3. As shown in Fig. 3, the locking device 5 includes a locking mechanism 50 that selectively establishes an unlocked state (see the two-dot chain line in the figure) that allows the lid 3 to be opened, and a locked state (see the solid line in the figure) that restricts the opening of the lid 3, and a locking solenoid 55 that drives the locking mechanism 50 to establish the locked state in response to energization.

[0023] The locking mechanism 50 of the locking device 5 includes a locking lever 51 and an engaged portion 53 fixed to the lid 3. The locking lever 51 is disposed on the end wall 23 side (the front side of the paper in FIG. 3 ) of a support portion 21s supported by one side wall 21 of the case body 2 so as to extend parallel to the closed lid 3. The center portion of the locking lever 51 in the longitudinal direction is supported by the support portion 21s so as to be rotatable about an axis extending parallel to the side wall 21. The engaged portion 53 is fixed to one end of the lid 3 so as to be inserted into an opening 21o formed at the outer end of the support portion 21s when the lid 3 is closed (fully closed). Furthermore, an engaging portion 52 is formed on one end (upper end) of the locking lever 51 so as to be engageable with the engaged portion 53 on the lid 3 inserted into the opening 21o.

[0024] The lock solenoid 55 is a pull solenoid that, when energized, draws a plunger connected to a shaft 57 into a coil. The lock solenoid 55 is fixed to the surface of the support portion 21s on the end wall portion 23 side so that the shaft 57 protrudes outward from the side wall portion 21. The shaft 57 of the lock solenoid 55 is rotatably connected to the other end (lower end) of the lock lever 51 via a pin connection. As a result, when the cover 3 is closed (fully closed) and current is supplied to the lock solenoid 55 (coil), the shaft 57 is drawn toward the coil, causing the engaging portion 52 of the lock lever 51 to rotate toward the opening 21o and engage with the engaged portion 53 protruding from the opening 21o toward the end wall portion 23. As a result, while the lock solenoid 55 is energized, the cover 3 is locked by the lock device 5 so that it cannot be opened. Note that the lock device 5 may include a push solenoid.

[0025] The two courtesy switches 6 are attached to the support portion 21s or the other side wall portion 21 of the case body 2 so as to be able to abut against the corresponding one of the two end portions of the lid body 3. Each courtesy switch 6 is a push-type open / close switch that is pressed to close by the lid body 3 being closed, and opens in response to the opening of the lid body 3. In this embodiment, each courtesy switch 6 is grounded so as to form a closed circuit when closed.

[0026] The battery case 1 configured as described above is also used in a battery charging device 80. That is, a plurality of battery cases 1 are arranged, for example, vertically in a housing 85 of the battery charging device 80 so as to define a battery storage section of the battery charging device 80 (see FIG. 2). In this embodiment, the battery transport cart 90 includes a battery mounting plate 95 corresponding to the bottom 20 of the case body 2, which is integrated with a pair of side walls 21, with both of the pair of side walls 21 partially removed. The battery transport cart 90 includes a cart body 91 including a base frame, a plurality of (at least three) casters, a handle, etc., and a top plate 92 supported by the cart body 91 (base frame) via a lifting mechanism (lifter) so as to be able to move up and down freely, and the battery mounting plate 95 is supported by the top plate 92 (cart body 91).

[0027] 4 is a control block diagram of the electric vehicle 100. As shown in the figure, the electric vehicle 100 includes a general electronic control unit (hereinafter referred to as "BEVECU") 200, a motor electronic control unit (hereinafter referred to as "MGECU") 300 that controls the PCU 110, and a battery electronic control unit (hereinafter referred to as "battery ECU") for managing multiple batteries 10. The BEVECU 200, MGECU 300, and battery ECU 400 all include a microcomputer having a CPU, ROM, RAM, input / output interface, etc., not shown, as well as various drive circuits, various logic ICs, etc., and exchange information (communication frames) with one another via a shared communication line (CAN bus) CB, etc.

[0028] The BEVECU 200 is connected to various sensors such as a start switch (IG switch) SS, an accelerator pedal position sensor, a shift position sensor, and a vehicle speed sensor. When the electric vehicle 100 is traveling, the BEVECU 200 sets a required torque for traveling based on the accelerator opening and the vehicle speed, and sets a torque command value for the motor generator MG based on the required torque, etc. Furthermore, the BEVECU 200 controls the opening and closing of the system main relay SMR and the power supply relay (IGCT relay) 120.

[0029] The power supply relay 120 is a normally open mechanical relay (contact relay) that can electrically connect an auxiliary battery (low-voltage battery) 130 of the electric vehicle 100 having a rated output voltage of, for example, about 12 V, the DC / DC converter of the PCU 110, and a low-voltage power line LL to which a plurality of auxiliaries including the MGECU 300 and the battery ECU 400 are connected. When the driver of the electric vehicle 100 turns on the start switch SS to request system startup of the electric vehicle 100, the BEVECU 200 supplies an excitation current based on power from the auxiliary battery 130, etc. to the coil of the power supply relay 120 to close the power supply relay 120. Closing the power supply relay 120 allows power from the auxiliary battery 130, etc. to be supplied to the various auxiliaries.

[0030] Furthermore, after closing the power supply relay 120, the BEVECU 200 executes predetermined processes such as determining whether the system main relay SMR is welded, overheated, or has a ground fault, and when a predetermined ready-on condition is met, closes the system main relay SMR. In this case, the BEVECU 200 supplies an excitation current based on power from the auxiliary battery 130 or the like to the coil of the system main relay SMR (positive side relay and negative side relay) to close the system main relay SMR. If a failure such as a welded (closed fault) of the system main relay SMR occurs during system startup, the BEVECU 200 turns on a predetermined warning light on a display provided on the instrument panel and transitions the electric vehicle 100 to a corresponding fail-safe mode.

[0031] Furthermore, when the driver turns off the start switch SS to request a system shutdown of the electric vehicle 100, the BEVECU 200 cuts off the supply of the excitation current and opens the system main relay SMR. Thereafter, the BEVECU 200 executes predetermined processes, such as a welding determination, an overheat determination, and a ground fault determination, for the system main relay SMR, and when predetermined conditions are met, cuts off the supply of the excitation current and opens the power supply relay 120. If a failure, such as a welding of the system main relay SMR, has occurred when a system shutdown is requested, the BEVECU 200 turns on a predetermined fail flag and then shuts down the system of the electric vehicle 100. In this case, the electric vehicle 100 transitions to a fail-safe mode the next time the start switch SS is turned on. In the electric vehicle 100, when the start switch SS is turned off, the display on the instrument panel is turned off.

[0032] As shown in FIG. 4 , the battery ECU 400 acquires detection values ​​from voltage sensors V1, V2, and V3 provided for each of the multiple batteries 10. The battery relays Rp and Rn of each battery 10 are electrically connected to the battery ECU 400 via connectors, receptacles, and power supply lines (not shown). While the power supply relay 120 is closed, the battery ECU 400 supplies an excitation current based on power supplied from the auxiliary battery 130 or the like via the power supply relay 120 to the coils of the battery relays Rp and Rn, thereby closing the battery relays Rp and Rn. Furthermore, the battery ECU 400 can cut off the supply of the excitation current to open the battery relays Rp and Rn. When at least one of the battery relays Rp and Rn is opened, a (closed circuit) including the multiple batteries 10, the PCU 110, the motor generator MG, and the like is opened, even if the system main relay SMR is closed.

[0033] Furthermore, the battery ECU 400 determines whether or not the battery relays Rp, Rn of each battery 10 are welded (closed fault) after the power supply relay 120 is closed in response to the start switch SS being turned on (and before the system main relay SMR is closed), and after the system main relay SMR is opened in response to the start switch SS being turned off. That is, when the start switch SS is turned on and the power supply relay 120 is closed, the battery ECU 400 determines whether or not one of the battery relays Rp, Rn of each battery 10 (for example, the battery relay Rp) is welded, as shown in Fig. 5. Note that in Fig. 5, relays Rp_1, Rn_1 indicate the battery relays Rp, Rn of the first battery 10, relays Rp_2, Rn_2 indicate the battery relays Rp, Rn of the second battery 10, and relays Rp_3, Rn_3 indicate the battery relays Rp, Rn of the third battery 10.

[0034] Specifically, when the power supply relay 120 is closed, the battery ECU 400 closes only the other of the battery relays Rp, Rn of each battery 10 (for example, battery relay Rn) (time t0 in FIG. 5 ), and determines whether or not one of the battery relays Rp, Rn of each battery 10 is welded based on the detected values ​​of the voltage sensors V1, V2, and V3. If the detected values ​​of the voltage sensors V1, V2, and V3 are all zero, the battery ECU 400, which serves as a failure determination device, determines that one of the battery relays Rp, Rn of each battery 10 is not welded, and closes one of the battery relays Rp, Rn of each battery 10, and transmits a notice of permission to close the system main relay SMR to the BEVECU 200 (time t1 in FIG. 5 ). In this case, the BEVECU 200 closes the system main relay SMR on the condition that the system main relay SMR and the like are normal (time t2 in FIG. 5 ). On the other hand, when it is determined that at least one of the battery relays Rp, Rn of each battery 10 is welded based on the detection values ​​of the voltage sensors V1, V2, V3, the battery ECU 400 turns on a predetermined warning light on a display provided on the instrument panel and transitions the electric vehicle 100 to a corresponding fail-safe mode.

[0035] Furthermore, when the start switch SS is turned off and the system main relay SMR is opened (time t3 in FIG. 5), the battery ECU 400 determines whether the other of the battery relays Rp, Rn of each battery 10 (for example, the battery relay Rn) is welded. Specifically, when the system main relay SMR is opened, the battery ECU 400 opens only the other of the battery relays Rp, Rn of each battery 10 (time t4 in FIG. 5), and determines whether the other of the battery relays Rp, Rn of each battery 10 is welded based on the detection values ​​of the voltage sensors V1, V2, and V3. If the detection values ​​of the voltage sensors V1, V2, and V3 are all zero, the battery ECU 400, which serves as a failure determination device, determines that the other of the battery relays Rp, Rn of each battery 10 is not welded, and opens one of the battery relays Rp, Rn of each battery 10, while transmitting a notice of permission to open the power supply relay 120 to the BEVECU 200 (time t5 in FIG. 5). When the BEVECU 200 receives the opening permission notification from the battery ECU 400, the BEVECU 200 opens the power supply relay 120 on the condition that the system main relay SMR and the like are normal.

[0036] 4, the lock solenoid 55 (coil) of the lock device 5 of the battery case 1 is connected to the above-mentioned low-voltage power line LL, and current is constantly supplied to the lock solenoid 55 from the auxiliary battery 130 or the like while the power supply relay 120 is closed. As a result, while the power supply relay 120 is closed, the lock solenoid 55 holds the lock lever 51 of the lock mechanism 50 in a state in which the engaging portion 52 is engaged with the engaged portion 53 inserted into the opening 21o. As a result, while the start switch SS is on and the power supply relay 120 is closed, the lid 3 of the battery case 1 is locked by the lock device 5 so that it cannot be opened.

[0037] Furthermore, as shown in Fig. 4, the two courtesy switches 6 of the battery case 1 are electrically connected to one end of a coil 150c of an interlock relay (circuit opening / closing relay) 150, which is a mechanical relay (contact relay), via a connector, a receptacle, and an electric wire (not shown). The other end of the coil 150c of the interlock relay 150 is connected to the above-mentioned low-voltage power line LL. Furthermore, one of the two contacts of the interlock relay 150 is electrically connected to a first terminal of the BEVECU 200, and the other of the two contacts is electrically connected to a second terminal of the BEVECU 200. The BEVECU 200 applies a voltage based on power from the auxiliary battery 130 or the like to the first terminal during the period from when the start switch SS is turned on to when it is turned off.

[0038] When the lid 3 of the battery case 1 is closed and at least one of the two courtesy switches 6 is closed, the courtesy switch 6 grounds one end of the coil 150c of the interlock relay 150. Therefore, when the lid 3 of the battery case 1 is closed and the power supply relay 120 is closed, an excitation current based on power from the auxiliary battery 130 or the like is supplied to the coil 150c, thereby closing the interlock relay 150. When the interlock relay 150 is closed, the first and second terminals of the BEVECU 200 are electrically connected via the interlock relay 150. The BEVECU 200 compares the voltages at the first and second terminals, and if the two voltages are approximately the same, determines that the interlock relay 150 is closed.

[0039] On the other hand, when the cover 3 of the battery case 1 is opened, even if the power supply relay 120 is closed, the supply of excitation current to the coil 150c is interrupted by opening each courtesy switch 6, i.e., by disconnecting the ground and opening the closed circuit, and the interlock relay 150 is opened. In this case, the electrical connection between the first and second terminals of the BEVECU 200 is released, and the voltage of the second terminal becomes zero. When the voltage of the second terminal drops (to zero), the BEVECU 200 determines that the cover 3 of the battery case 1 has been opened, each courtesy switch 6 has been opened, and the interlock relay 150 has been opened, and then interrupts the supply of excitation current to the system main relay SMR, opening the system main relay SMR. This opens the high-voltage circuit (closed circuit) including the multiple batteries 10, the PCU 110, the motor generator MG, etc.

[0040] In addition, as shown in Fig. 4, a light emitter 140 serving as an informing device is electrically connected to the battery ECU 400. The light emitter 140 includes a light-emitting diode or the like, and is installed near the battery case 1 on the floor panel of the electric vehicle 100, i.e., in front of the lid 3, so that it can be identified by an operator (user) replacing the battery 10 when the lid 3 of the battery case 1 is closed (see Fig. 2). However, the light emitter 140 may be installed on the battery case 1 as long as it can be identified by an operator when the lid 3 of the battery case 1 is closed. While the start switch SS is turned on and the power supply relay 120 is closed, the battery ECU 400 supplies an excitation current based on power supplied from the auxiliary battery 130 or the like via the power supply relay 120 to the light emitter 140, causing the light emitter 140 to light up (emit light).

[0041] That is, in the electric vehicle 100, while the start switch SS is turned on and the power supply relay 120 is closed, the lid 3 of the battery case 1 is locked by the locking device 5 so that it cannot be opened, and the light emitter 140 installed near the battery case 1 is illuminated. Therefore, the light emitter 140 functions as an alarm device that notifies that the lid 3 of the battery case 1 is locked. In addition, the battery ECU 400 can blink the light emitter 140 by intermittently supplying an excitation current.

[0042] As described above, the electric vehicle 100 includes a plurality of replaceable batteries 10 and a motor generator MG that exchanges power with the plurality of batteries 10, and is capable of running using power from the motor generator MG. The electric vehicle 100 further includes a battery case 1 that includes a case body 2 having an opening 2o through which the plurality of batteries 10 are inserted and removed, and a lid 3 that opens and closes the opening 2o of the case body 2, and a locking device 5 that locks the lid 3 so that it cannot be opened at least when the start switch SS of the electric vehicle 100 is turned on.

[0043] More specifically, the lid 3 of the battery case 1 is locked so that it cannot be opened while the start switch SS of the electric vehicle 100 is turned on and the power supply relay 120 is closed. This effectively prevents a worker attempting to replace a battery 10 from touching the battery 10 when a high-voltage circuit (closed circuit) including multiple batteries 10, the PCU 110, the motor generator MG, etc. is formed in the electric vehicle 100, or when there is a possibility that the high-voltage circuit will be formed after the start switch SS is turned on. As a result, safety during battery 10 replacement in the electric vehicle 10 can be effectively ensured.

[0044] The locking device 5 of the battery case 1 includes a locking mechanism 50 that selectively establishes an unlocked state that allows the lid 3 to be opened and a locked state that restricts the opening of the lid 3, and a locking solenoid 55 that drives the locking mechanism 50 to establish the locked state in response to energization. The locking solenoid 55 of the locking device 5 is connected to a power source such as the auxiliary battery 130 via a power supply relay 120 that is closed in response to the start switch SS being turned on. This makes it possible to reliably operate the locking device 5 when the start switch SS is turned on while suppressing the complexity of control in the electric vehicle 100.

[0045] Furthermore, in the electric vehicle 100, the lock solenoid 55 is supported by the case body 2 of the battery case 1. The lock mechanism 50 includes a lock lever 51 rotatably supported by the case body 2, and the lock lever 51 is rotationally driven by the lock solenoid 55 to engage with an engaged portion 53 provided on the lid 3. This allows the lock devices 5 to be concentrated on the battery case 1 side, further improving the ease of assembly of the battery case 1 to the electric vehicle 100 and versatility. However, the lock device 5 may also be installed on the vehicle body side of the electric vehicle 100, such as on a floor panel.

[0046] The battery case 1 of the electric vehicle 100 also includes multiple courtesy switches 6 that detect whether the cover 3 is open or closed. Each courtesy switch 6 closes when the cover 3 is closed, allowing a high-voltage circuit (closed circuit) including the multiple batteries 10, the PCU 110, the motor generator MG, etc. to be closed, and opens when the cover 3 is open, prohibiting the high-voltage circuit from being closed. This prevents a high-voltage circuit through which current from the battery 10 flows when the cover 3 of the battery case 1 is open, thereby further ensuring safety when replacing the battery 10. However, the battery case 1 may include a single courtesy switch 6.

[0047] Furthermore, the electric vehicle 100 includes an interlock relay (circuit opening / closing relay) 150 that opens and closes a high-voltage circuit (closed circuit) including the multiple batteries 10, the PCU 110, the motor generator MG, etc., in cooperation with the BEVECU 200. That is, the interlock relay 150 closes when an excitation current is supplied to the coil 150c, allowing the high-voltage circuit to be closed, and opens when an excitation current is not supplied to the coil 150c, prohibiting the high-voltage circuit from being closed. Furthermore, each courtesy switch 6 of the battery case 1 closes when the cover 3 is closed, allowing the supply of excitation current to the interlock relay 150 (coil 150c), and opens when the cover 3 of the battery case 1 is opened, blocking the supply of excitation current to the interlock relay 150. This makes it possible to more reliably prevent a high-voltage circuit through which current flows from the multiple batteries 10 when the cover 3 of the battery case 1 is open.

[0048] In the above embodiment, the interlock relay 150 has a function of notifying the BEVECU 200 of the open / closed state of the cover 3 of the battery case 1, but this is not limited thereto. That is, the interlock relay 150 may, for example, cut off the supply of excitation current to the system main relay SMR when the courtesy switch 6 is open. Furthermore, instead of providing the voltage sensors V1, V2, and V3 in the electric vehicle 100 or the battery case 1 described above, a voltage sensor V1, V2, or V3 that detects the voltage between the positive receptacle 4p and the negative receptacle 4n may be provided in the pack case of each battery 10. Furthermore, a capacitor may be provided between the positive receptacle 4p and the negative receptacle 4n of each battery 10. In this case, a single voltage sensor may be provided in the electric vehicle 100 or the battery case 1. Furthermore, each battery 10 may be provided with an indicator lamp that lights up when the battery relay Rp or Rn is closed. Furthermore, the battery case 1 may be mounted on a moving body other than the electric vehicle 100, such as a railway vehicle, or may be installed on fixed equipment other than the battery charging device 80. The battery case 1 may also be configured to house a single replaceable battery 10. Furthermore, the case body 2 of the battery case 1 may be defined by the body of the electric vehicle 100, and a part of the case body 2 may be formed by a part of the body of the electric vehicle 100.

[0049] The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present disclosure. Furthermore, the above-described embodiment is merely a specific form of the invention described in the Summary of the Invention, and does not limit the elements of the invention described in the Summary of the Invention. [Industrial Applicability]

[0050] The invention of the present disclosure can be used in the electric vehicle manufacturing industry and the like. [Explanation of symbols]

[0051] 1 battery case, 2 case body, 2o opening, 21 side wall portion, 21o opening, 21s support portion, 3 lid body, 5 locking device, 50 locking mechanism, 51 lock lever, 52 engaging portion, 53 engaged portion, 55 lock solenoid (solenoid), 57 shaft, 6 courtesy switch (switch), 10 battery, 100 electric vehicle, 110 power control unit (PCU), 120 power supply relay (relay), 130 auxiliary battery, 140 light emitter (alarm device), 150 interlock relay (circuit opening / closing relay), 200 overall electronic control unit (BEVECU), 400 battery electronic control unit (battery ECU), MG motor generator, Rp, Rn battery relay (relay), SMR system main relay, SS start switch, V1, V2, V3 voltage sensors.

Claims

1. An electric vehicle including at least one replaceable battery and an electric motor that exchanges electric power with the battery, and that can run using power from the electric motor, a battery case including a case body having an opening into which the battery is inserted and removed, and a lid body that opens and closes the opening of the case body; a locking device that locks the cover so that it cannot be opened at least when a start switch of the electric vehicle is turned on; An electric vehicle equipped with:

2. The electric vehicle according to claim 1, the locking device includes a locking mechanism that selectively establishes an unlocked state that allows the lid body to be opened and a locked state that restricts the lid body from being opened, and a solenoid that drives the locking mechanism to establish the locked state in response to energization, In an electric vehicle, the solenoid of the locking device is connected to a power source via a relay that is closed in response to the start switch being turned on.

3. The electric vehicle according to claim 2, The solenoid is supported by the case body, The locking mechanism is rotatably supported by the case body, and includes a locking lever that is rotationally driven by the solenoid and engages with an engagement portion provided on the cover body.

4. The electric vehicle according to any one of claims 1 to 3, the battery case includes a switch that detects whether the lid is open or closed, The switch allows the closed circuit to be closed when the cover is closed, and prohibits the closed circuit including the battery from being closed when the cover is open.

5. The electric vehicle according to claim 4, a circuit opening / closing relay that closes when an exciting current is supplied to allow the closed circuit to be closed, and that opens when the exciting current is not supplied to prohibit the closed circuit from being closed; The switch closes when the cover is closed to allow the supply of the excitation current to the circuit opening / closing relay, and opens when the cover is opened to cut off the supply of the excitation current to the circuit opening / closing relay.

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