Fuel cell stack

Abstract

To provide a fuel cell stack that allows a user to select whether to enable a termination resistor.SOLUTION: A fuel cell stack 1 includes a cell stack 3 in which a number of fuel cells are stacked, and is equipped with a cell monitor 4 that monitors the voltage of the cell stack 3, a communication wire harness 5 connected to the cell monitor 4, and an IF connector 6 that can be connected to the communication wire harness 5 from outside the fuel cell stack 1. The communication wire harness 5 includes a termination resistor 7. The IF connector 6 includes a connection pin that can be electrically connected to the termination resistor 7.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a fuel cell stack. [Background technology]

[0002] Conventionally, one such technical field is described, for example, in Patent Document 1. The fuel cell stack described in Patent Document 1 includes a cell stack in which multiple fuel cell cells are stacked, a cell monitor that monitors the cell stack, a control device that communicates with the cell monitor via a communication wire harness, a first case that houses the cell stack, and a second case that houses the control device. In this fuel cell stack, the communication connector of the communication wire harness that connects the control device and the cell monitor is connected to a connection connector provided in the connector portion of the cell monitor through a connector opening in the second case, thereby facilitating connection between the cell monitor and the control device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-224403 A Summary of the Invention [Problem to be solved by the invention]

[0004] When selling fuel cell stacks, some users desire one-to-one CAN communication with the fuel cell stack, while others desire multiple CAN communications. It is required to be able to freely select whether to enable or disable the termination resistance on the fuel cell stack side according to the user's communication preferences. However, in the above-mentioned fuel cell stack, a termination resistance is implemented in the cell monitor, and the fuel cell stack is fixed to have a termination resistance, so there is a problem that it cannot be applied to the above-mentioned selection.

[0005] The present invention has been made to solve the above technical problems, and has an object to provide a fuel cell stack in which it is possible to select whether a termination resistor is enabled or disabled. [Means for solving the problem]

[0006] The fuel cell stack of the present invention is a fuel cell stack including a cell stack in which a plurality of fuel cell cells are stacked, and is characterized in that it comprises a cell monitor that monitors the voltage of the cell stack, a communication wire harness connected to the cell monitor, and a connector that can be connected to the communication wire harness from outside the fuel cell stack, wherein the communication wire harness has a termination resistor, and the connector has a connection pin that can be electrically connected to the termination resistor.

[0007] In the fuel cell stack according to the present invention, the communication wire harness has a termination resistor, and the connector has a connection pin that can be electrically connected to the termination resistor, so that if the user wants to enable the termination resistor on the fuel cell stack side, this can be achieved by connecting it to the connection pin in the connector that is electrically connected to the termination resistor. In this way, for example, it is possible to use the termination resistor on the fuel cell stack side and the termination resistor provided in the user's system, and one-to-one communication can be performed with the fuel cell stack. On the other hand, if the user wants to disable the termination resistor on the fuel cell stack side, multiple communications can be achieved with the fuel cell stack by not connecting it to the connection pin that is electrically connected to the termination resistor in the connector, and by using, for example, a termination resistor provided in the user's system. Effect of the Invention

[0008] According to the present invention, it is possible to select whether the termination resistor on the fuel cell stack side is enabled or disabled. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic diagram showing a structure of a fuel cell stack according to an embodiment; [Figure 2A]FIG. 1 is a schematic diagram showing one-to-one CAN communication. [Figure 2B] FIG. 2 is a schematic diagram for explaining a connection for one-to-one CAN communication. [Figure 3A] FIG. 1 is a schematic diagram showing multiple CAN communications. [Figure 3B] FIG. 2 is a schematic diagram for explaining connections of multiple CAN communications. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of a fuel cell stack according to the present invention will be described with reference to the drawings. In the description of the drawings, the same elements are given the same reference numerals, and duplicated description will be omitted. In addition, in the CAN (Controller Area Network) communication described below, a differential transmission line having a high-potential side signal line and a low-potential side signal line is used, and the potential of the high-potential side signal line is indicated by "CANH" and the potential of the low-potential side signal line is indicated by "CANL".

[0011] Fig. 1 is a schematic diagram showing the structure of a fuel cell stack according to an embodiment. As shown in Fig. 1, a fuel cell stack 1 of this embodiment includes a box-shaped stack case 2, a cell stack 3 housed inside the stack case 2, a cell monitor 4, and a communication wire harness 5, and an IF (Interface) connector 6 attached to a side wall of the stack case 2.

[0012] The cell laminate 3 is a cell stack formed by stacking a plurality of fuel cells, and constitutes a solid polymer electrolyte fuel cell. Although not shown, the fuel cell has a membrane / electrode assembly in which a polymer electrolyte membrane is sandwiched between an anode electrode and a cathode electrode, and a pair of separators that sandwich the membrane / electrode assembly from both sides. The fuel cell generates electricity by an oxidation-reduction reaction between oxygen gas in the air supplied through the separator on the cathode electrode side and hydrogen gas supplied through the separator on the anode electrode side.

[0013] The stack case 2 is formed in a rectangular box shape from a metal material such as aluminum. The cell monitor 4 is for monitoring the voltage of the cell stack 3. In this embodiment, there are two cell monitors 4 (a first cell monitor 4a and a second cell monitor 4b). An ECU (Electronic Control Unit) is disposed in each cell monitor. Furthermore, no termination resistor is implemented in the ECU in each cell monitor.

[0014] The communication wire harness 5 is electrically connected to the ECU of the first cell monitor 4a and the ECU of the second cell monitor 4b, for example, via a connector. One end of the communication wire harness 5 extends to a side wall of the stack case 2 and is electrically connected to an IF connector 6. In this embodiment, the communication wire harness 5 is configured to have a termination resistor 7.

[0015] The IF connector 6 is fixed to the side wall of the stack case 2 while penetrating the side wall of the stack case 2 so that it can be connected to the communication wire harness 5 from outside the fuel cell stack 1. This IF connector 6 is a connector provided to connect the communication wire harness 5 to a user's system, and is configured to have a power supply connection pin, a GND (Ground) connection pin, a CAN communication connection pin for each cell monitor, and a termination resistor connection pin.

[0016] 2B and 3B, the IF connector 6 has eight connection pins, including a power connection pin, a GND connection pin, an ECU(1) CANH connection pin, an ECU(1) CANL connection pin, an ECU(2) CANH connection pin, an ECU(2) CANL connection pin, a termination resistor CANH connection pin, and a termination resistor CANL connection pin. These pins protrude outward from the IF connector 6.

[0017] The end portion of the power supply connection pin (i.e., the end portion opposite the end portion protruding outward from the IF connector 6) is electrically connected to the power supply of the first cell monitor 4a and the power supply of the second cell monitor 4b, respectively, via the communication wire harness 5. The end portion of the GND connection pin is electrically connected to the GND of the first cell monitor 4a and the GND of the second cell monitor 4b, respectively, via the communication wire harness 5. Furthermore, the end portion of this GND connection pin is also electrically connected to the GND of the termination resistor 7 of the communication wire harness 5.

[0018] An end of the ECU(1) CANH connection pin is electrically connected to the CANH of the ECU of the first cell monitor 4a (shown as "ECU(1) CANH" in Figs. 2B and 3B) via a communication wire harness 5. An end of the ECU(1) CANL connection pin is electrically connected to the CANL of the ECU of the first cell monitor 4a (shown as "ECU(1) CANL" in Figs. 2B and 3B) via a communication wire harness 5.

[0019] An end of the ECU(2) CANH connection pin is electrically connected to the CANH of the ECU of the second cell monitor 4b (shown as "ECU(2) CANH" in Figs. 2B and 3B) via a communication wire harness 5. An end of the ECU(2) CANL pin is electrically connected to the CANL of the ECU of the second cell monitor 4b (shown as "ECU(2) CANL" in Figs. 2B and 3B) via a communication wire harness 5.

[0020] An end portion of the termination resistor CANH connection pin is electrically connected to the CANH of the termination resistor 7 of the communication wire harness 5, and an end portion of the termination resistor CANL connection pin is electrically connected to the CANL of the termination resistor 7 of the communication wire harness 5.

[0021] Hereinafter, it will be described with reference to Figs. 2A to 3B that the fuel cell stack 1 of this embodiment is compatible with both one-to-one CAN communication and multiple CAN communication.

[0022] [One-to-one CAN communication] Fig. 2A is a schematic diagram showing one-to-one CAN communication, and Fig. 2B is a schematic diagram for explaining the connection of one-to-one CAN communication. As shown in Fig. 2A, when one-to-one CAN communication is performed with the fuel cell stack 1 in a user-side system of the fuel cell stack 1, the user electrically connects the IF connector 6 of the fuel cell stack 1 to the ECU 11 of the ECU assembly 10 on the user side via the CAN communication bus 8. The ECU 11 of the ECU assembly 10 on the user side is equipped with a termination resistor 12. The CAN communication bus 8 can be electrically connected to the IF connector 6 via a connector (not shown) that can be mated with the IF connector 6, for example.

[0023] As shown in FIG. 2B, the ECU 11 of the ECU assembly 10 on the user side is provided with, for example, a power supply, GND, ECU(1) CANH, ECU(1) CANL, ECU(2) CANH, ECU(2) CANL, termination resistors CANH and CANL.

[0024] At this time, the power supply, GND, ECU(1) CANH, ECU(1) CANL, ECU(2) CANH, and ECU(2) CANL of the ECU 11 of the ECU assembly 10 on the user side are electrically connected to the power supply connection pin, GND connection pin, ECU(1) CANH connection pin, ECU(1) CANL connection pin, ECU(2) CANH connection pin, and ECU(2) CANL connection pin of the IF connector 6, respectively, via the CAN communication bus 8.

[0025] Furthermore, the termination resistors CANH and CANL on the user-side ECU assembly 10 side are also electrically connected to the termination resistor CANH connection pin and termination resistor CANL connection pin, respectively, of the IF connector 6. In other words, at this time, the termination resistor 7 on the fuel cell stack 1 side is selected as valid. This enables one-to-one CAN communication to be performed between the fuel cell stack 1 and the user-side system.

[0026] In CAN communication, it is necessary to use two termination resistors in order to prevent communication errors, etc. As described above, by using both the termination resistor 7 on the fuel cell stack 1 side and the termination resistor 12 on the user's ECU assembly 10, it is possible to maintain the quality of the CAN communication between the fuel cell stack 1 and the user's system.

[0027] [Multiple CAN communications] Fig. 3A is a schematic diagram showing a plurality of CAN communications, and Fig. 3B is a schematic diagram for explaining the connection of a plurality of CAN communications. As shown in Fig. 3A and Fig. 3B, for example, in a user-side system of a fuel cell stack 1, when a plurality of CAN communications are performed between the fuel cell stack 1 and the user-side ECU assembly 10, when the user electrically connects the IF connector 6 of the fuel cell stack 1 to the ECU 11 of the user-side ECU assembly 10 via the CAN communication bus 8, the power supply, GND, ECU(1)CANH, ECU(1)CANL, ECU(2)CANH, and ECU(2)CANL of the user-side ECU 11 are electrically connected to the power supply connection pin, GND connection pin, ECU(1)CANH connection pin, ECU(1)CANL connection pin, ECU(2)CANH connection pin, and ECU(2)CANL connection pin of the IF connector 6, respectively, via the CAN communication bus 8. However, the termination resistor CANH and termination resistor CANL of the user-side ECU 11 are not electrically connected to the termination resistor CANH connection pin and termination resistor CANL connection pin of the IF connector 6, respectively. In other words, the termination resistor 7 on the fuel cell stack 1 side is selected as invalid.

[0028] This allows multiple CAN communications to be performed between the fuel cell stack 1 and the user's system. In this case, the user's ECU 11 has two termination resistors 12, and by using these termination resistors 12, the quality of the CAN communications between the fuel cell stack 1 and the user's system can be maintained.

[0029] In the fuel cell stack 1 according to this embodiment, the communication wire harness 5 has a termination resistor 7, and the IF connector 6 has connection pins (termination resistor CANH connection pin, termination resistor CANL connection pin) that can be electrically connected to the termination resistor 7. Therefore, if the user wants to enable the termination resistor 7 on the fuel cell stack 1 side, this can be achieved by connecting the termination resistor CANH and termination resistor CANL of the ECU 11 on the user side to the termination resistor CANH connection pin and termination resistor CANL connection pin of the IF connector 6. This makes it possible to use the termination resistor 7 on the fuel cell stack 1 side and the termination resistor 12 of the ECU 11 on the user side, and one-to-one CAN communication can be performed with the fuel cell stack 1. On the other hand, if the user wants to disable the termination resistor 7 on the fuel cell stack 1 side, multiple CAN communications can be achieved with the fuel cell stack 1 by not connecting the termination resistor CANH and termination resistor CANL of the ECU 11 to the termination resistor CANH connection pin and termination resistor CANL connection pin of the IF connector 6, and by using, for example, two termination resistors 12 on the user side.

[0030] Furthermore, by using a fuel cell stack 1 having such an identical structure, it is possible to accommodate one-to-one or multiple CAN communications on the user's side, thereby enabling cost reduction compared to developing, for example, a fuel cell stack with termination resistance that is suitable exclusively for one-to-one CAN communication and a fuel cell stack without termination resistance that is suitable exclusively for multiple CAN communications.

[0031] Furthermore, in the fuel cell stack 1 according to this embodiment, no termination resistor is implemented in the cell monitors 4 (first cell monitor 4a and second cell monitor 4b), i.e., the cell monitors are not provided with termination resistors. This allows the wiring from the first cell monitor 4a to the second cell monitor 4b in the fuel cell stack to be treated as a branch line, allowing the user to freely set the main line and improving the robustness of the wiring required for component mounting, etc.

[0032] Specifically, main lines need to be arranged with a possible wiring length of less than 15 m, and branch lines need to be arranged with a possible wiring length of less than 5 m. In a fuel cell stack, the wiring from a component that has a termination resistance (e.g., the first cell monitor 4a that has a termination resistance) to a component that has a termination resistance (e.g., the second cell monitor 4b that has a termination resistance) is called the main line, and the wiring from a component that does not have a termination resistance to the connection to the CAN communication bus is called the branch line.

[0033] For example, when a termination resistor is provided in the cell monitor as in the conventional method, the wiring between the two cell monitors (the first cell monitor 4a and the second cell monitor 4b) in the fuel cell stack constitutes the main line. As a result, the wiring in the user's system is treated as a branch line, and only wiring of less than 5 m can be possible. On the other hand, when a termination resistor is not provided in the cell monitor as in this embodiment and a termination resistor is provided in the communication wire harness 5, the wiring from the fuel cell stack 1 to the user's system can be configured as the main line, or the wiring within the user's system can be configured as the main line, respectively, allowing the user to freely set the main line to suit their own system. As a result, the robustness of the wiring required for mounting parts, etc. can be improved.

[0034] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various design modifications can be made without departing from the spirit of the present invention as described in the claims. [Explanation of symbols]

[0035] 1: fuel cell stack, 2: stack case, 3: cell stack, 4: cell monitor, 4a: first cell monitor, 4b: second cell monitor, 5: communication wire harness, 6: IF connector, 7: termination resistor, 8: CAN communication bus, 10: user-side ECU assembly, 11: ECU, 12: termination resistor

Claims

[Claim 1] A fuel cell stack including a cell stack in which a plurality of fuel cell units are stacked, a cell monitor for monitoring a voltage of the cell stack; A communication wire harness connected to the cell monitor; a connector that can be connected to the communication wire harness from outside the fuel cell stack; Equipped with The communication wire harness has a termination resistor, The connector has a connection pin that can be electrically connected to the termination resistor.

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