Thermoelectric module for use in a vehicle system

A vehicle system includes a vehicle component, a battery, and a thermoelectric module coupled to the component to allow heat transfer between the catalytic converter and the thermoelectric module, wherein the thermoelectric module is electrically connected to the battery. The vehicle system further includes a temperature sensor coupled to the vehicle component. The temperature sensor is configured to measure the temperature of the vehicle component. The vehicle system further includes a controller in electronic communication with the thermoelectric module. The controller is programmed to switch the thermoelectric module among the heating mode, the cooling mode, and the power-generation mode based on the temperature of the vehicle component. The vehicle component may be an exhaust manifold, a turbocharger turbine housing, an exhaust gas conduit coupled between an exhaust manifold and a catalytic converter, and/or a catalytic converter.

INTRODUCTION

The present disclosure relates to a thermoelectric module for use in a vehicle system.

Vehicles include vehicle components, such as catalytic converters, that may need heating or cooling. For example, it may be desirable to heat or cool a catalytic converter to optimize its efficiency. Further, vehicle components (e.g., catalytic converters) may generate excess heat that may be used for other purposes.

SUMMARY

It is therefore desirable to develop a system for heating and cooling vehicle components. It is also desirable to convert the excess heat from a vehicle component into electrical energy.

The present disclosure describes a thermoelectric module that provides optimized temperature of the catalytic converter (or other vehicle component) by using Peltier heater/cooler functions. This thermoelectric module could also be used as a thermoelectric self-power generator utilizing the engine waste heat when the heating and cooling functions are not needed. The present disclosure also describes a method for controlling the thermoelectric module. By executing this method, the vehicle emissions are minimized by enhancing catalyst light-off and reducing cold start soot creation. Further, by utilizing this method, the electric power generation is possible using waste heat from the after-treatment system. Also, by utilizing this method, the fuel economy of the vehicle system is enhanced by reducing the need for enrichment.

To minimize vehicle emissions, faster control of catalytic converter temperature is desirable. During a cold start, catalytic converter light-off should occur within 15-20 seconds, especially for gasoline engines. During hot engine running, cooling of the exhaust manifold and catalytic converter are desirable to protect the components and meet the engine power demand. The presently disclosed vehicle system combines both thermoelectric heating and cooling, in addition to power generation into one thermoelectric module. The thermoelectric module is directly mounted on the outer surface of the catalytic converter and exhaust vehicle components to heat the catalyst during cold starts, while cooling the catalyst and/or exhaust vehicle components during overheating. P-type and n-type materials will be alternately deposited and connected to a rechargeable battery. A controller (with the assistance of temperature sensors) decides the direction of electrical current applied to either heat or cool exhaust components to maintain the desired temperatures and maintain the optimized catalytic efficiency. When the exhaust temperature is within the desired range, this thermoelectric module may be converted into a thermoelectric power generator to create electricity via thermal gradient from catalytic converter/exhaust to outer surface of the vehicle component, thus harvesting electrical energy through the exhaust waste heat.

In certain embodiments, an after-treatment system includes a catalytic converter and a thermoelectric module coupled to the catalytic converter to allow heat transfer between the catalytic converter and the thermoelectric module. The thermoelectric module has: (a) a heating mode in which the thermoelectric module heats the catalytic converter; (b) a cooling mode in which the thermoelectric module cools the catalytic converter; (c) a power-generation mode in which the thermoelectric module converts a temperature gradient of the catalytic converter directly into electrical energy. The after-treatment system further includes a temperature sensor coupled to the catalytic converter. The temperature sensor is configured to measure a temperature of the catalytic converter. The temperature sensor is configured to generate a signal indicative of the temperature of the catalytic converter. The after-treatment system further includes a controller in electronic communication with the thermoelectric module, wherein the controller is programmed to: determine the temperature of the catalytic converter based on the signal received from the temperature sensor and switch the thermoelectric module among the heating mode, the cooling mode, and the power-generation mode based on the temperature of the catalytic converter. The controller is further programmed to determine that the temperature of the catalytic converter is less than a light-off temperature of the catalytic converter and, in response to determining that the temperature of the catalytic converter is less than a light-off temperature of the catalytic converter, switch the thermoelectric module to operate in the heating mode to heat the catalytic converter.

The controller is further programmed to: determine that the temperature of the catalytic converter is less than a predetermined maximum temperature in response to determining that the temperature of the catalytic converter is less than a predetermined maximum temperature, switch the thermoelectric module to operate in the power-generation mode to generate the electrical energy directly from a temperature gradient of the catalytic converter. The controller is further programmed to switch the thermoelectric module to operate in the power-generation mode to generate the electrical energy directly from the temperature gradient of the catalytic converter in response to determining that the temperature of the catalytic converter is less than the predetermined maximum temperature and determining that the temperature of the catalytic converter is greater than the light-off temperature of the catalytic converter. The controller is further programmed to: in response to determining that the temperature of the catalytic converter is greater than the predetermined maximum temperature, switch the thermoelectric module to operate in the cooling mode to cool the catalytic converter. The controller is programmed to: switch the thermoelectric module to operate in the cooling mode to cool the catalytic converter in response to determining that the temperature of the catalytic converter is greater than the predetermined maximum temperature and determining that the temperature of the catalytic converter is greater than the light-off temperature of the catalytic converter. The thermoelectric module is in direct contact with the catalytic converter. The thermoelectric module is electrically coupled to a battery.

The present disclosure also describes a method for operating a vehicle system. The method includes determining a temperature of a catalytic converter and heating the catalytic converter using a thermoelectric module in response to determining that the temperature of the catalytic converter is less than a light-off temperature of the catalytic converter. Further, the method includes supplying electrical energy to a battery using the thermoelectric module in response to determining that the temperature of the catalytic converter is less than the predetermined maximum temperature. Supplying the electrical energy to the battery using the thermoelectric module occurs in response to determining that the temperature of the catalytic converter is less than the predetermined maximum temperature and determining that the temperature of the catalytic converter is greater than the light-off temperature of the catalytic converter. The method further includes cooling the catalytic converter using the thermoelectric module in response to determining that the temperature of the catalytic converter is greater than a predetermined maximum temperature. Cooling the catalytic converter using the thermoelectric module occurs in response to determining that the temperature of the catalytic converter is greater than the predetermined maximum temperature and determining that the temperature of the catalytic converter is greater than the light-off temperature of the catalytic converter.

The present disclosure also describes a vehicle system. The vehicle system includes a vehicle component, a battery, and a thermoelectric module coupled to the component to allow heat transfer between the catalytic converter and the thermoelectric module, wherein the thermoelectric module is electrically connected to the battery. The thermoelectric module is configured to operate as described above. The vehicle system further includes a temperature sensor coupled to the vehicle component. The temperature sensor is configured to measure the temperature of the vehicle component. The vehicle system further includes a controller in electronic communication with the thermoelectric module. The controller is programmed to switch the thermoelectric module among the heating mode, the cooling mode, and the power-generation mode based on the temperature of the vehicle component. The vehicle component may be an exhaust manifold, a turbocharger turbine housing, an exhaust gas conduit coupled between an exhaust manifold and a catalytic converter, and/or a catalytic converter.

DETAILED DESCRIPTION

With reference toFIG. 1, a vehicle system10includes a plurality of vehicle components11, such an internal combustion engine12for propulsion. The internal combustion engine12is configured to combust an air-fuel mixture to propel the vehicle system10. The vehicle system10may be a car, a truck, agricultural equipment, or other suitable system capable of transporting objects and/or passengers. The vehicle system10further includes an intake manifold14in fluid communication with the internal combustion engine12. The intake manifold14is configured to receive intake gases and direct the intake gases to the internal combustion engine12. The vehicle system10further includes an exhaust manifold16(i.e., one of the vehicle components11) in fluid communication with the internal combustion engine12. After combustion, the internal combustion engine12generates exhaust gases, and the exhaust gases flow from the internal combustion engine12to the exhaust manifold16.

The vehicle system10further includes a turbocharger18configured to maximize the efficiency and power output of the internal combustion engine12by forcing pressured air into the internal combustion engine12through the intake manifold14. The turbocharger18includes a compressor20having a compressor inlet22configured to receive intake gases. The compressor20also has a compressor outlet24in fluid communication with the intake manifold14. The compressor20is configured to pressurize the intake gases received through the compressor inlet22. Then, the pressurized intake gases exit the compressor20through the compressor outlet24. The compressor outlet24is in fluid communication with an intercooler26through a first intake conduit28. The intercooler26is a heat exchanger that removes waste heat in the pressurized intake gases exiting from the compressor20. A second intake conduit30fluidly couples the intercooler26to the intake manifold14. As such, the intake gases flow from the intercooler26to the intake manifold14. In some embodiments, the vehicle system10does not include the turbocharger18.

The turbocharger18further includes a turbine32(i.e., one of the vehicle components11) including a turbocharger turbine housing34. The turbine32is configured to generate power as gases flowing through it. A shaft36interconnects the compressor20and the turbine32. As a result, rotation of the turbine32causes the compressor20to rotate. The exhaust manifold16is in fluid communication with the turbine32through a first exhaust conduit38(i.e., one of the vehicle components11). As such, the exhaust gases flow from the exhaust manifold16to the turbine32, causing the turbine wheel (not shown) of the turbine32to rotate. This rotation of the turbine wheel of the turbine32causes the shaft36to rotate. In turn, the rotation of the shaft36causes the compressor wheel (not shown) of the compressor20to rotate.

The vehicle system10further includes an after-treatment system40including a catalytic converter42(i.e., one of the vehicle components11) configured to treat unturned hydrocarbons, carbon monoxide and various nitrogen oxides procured from the combustion of the internal combustion engine12. The after-treatment system includes a second exhaust conduit44(i.e., one of the vehicle components11) fluidly interconnecting the turbine32and the catalytic converter42. As such, exhaust gases flow from the turbine32to the catalytic converter42. A bypass conduit46(i.e., one of the vehicle components11) is fluidly coupled between the exhaust manifold16and the catalytic converter42to bypass the turbine32. In the depicted embodiment, the bypass conduit46is directly connected to the first exhaust conduit38and the second exhaust conduit44to bypass the turbine32. A wastegate valve48is coupled between the bypass conduit46and the first exhaust conduit38. Consequently, the wastegate valve48has a first valve position and a second valve position. In the first valve position, the wastegate valve48directs exhaust gases from the exhaust manifold16directly into the turbine32. In the second valve position, the wastegate valve48directs exhaust gases directly from the exhaust manifold16to the second exhaust conduit44, thereby bypassing the turbine32.

The after-treatment system40further includes a main exhaust flow conduit50in fluid communication with the catalytic converter42. Accordingly, the exhaust gases flow from the catalytic converter42to the main exhaust flow conduit50. The main exhaust flow conduit50has an exhaust gas discharge end52to allow the exhaust gases to exit the after-treatment system40.

The vehicle system10further includes a controller54. The terms “controller,” “control module,” “control,” “control unit,” “processor” and similar terms mean one or various combinations of one or more of Application Specific Integrated Circuit(s) (ASIC), electronic circuit(s), central processing unit(s) (preferably microprocessor(s)) and associated memory and storage (read only, programmable read only, random access, hard drive, etc.) executing one or more software or firmware programs or routines, combinational logic circuit(s), sequential logic circuit(s), input/output circuit(s) and devices, appropriate signal conditioning and buffer circuitry, and other components to provide the described functionality. “Software,” “firmware,” “programs,” “instructions,” “routines,” “code,” “algorithms” and similar terms mean controller executable instruction sets including calibrations and look-up tables. The controller54may alternatively be configured as a central processing unit (CPU). The controller54may include a processor57(e.g., a microprocessor) and at least one memory58, at least some of which is tangible and non-transitory. The memory58is configured to store controller executable instruction sets, and the processor can execute the controller executable instruction sets stored in the memory. The memory58may be a recordable medium that participates in providing computer-readable data or process instructions. Such a medium may take many forms, including but not limited to non-volatile media and volatile media. Non-volatile media for the controller54may include, for example, optical or magnetic disks and other persistent memory. Volatile media may include, for example, dynamic random-access memory (DRAM), which may constitute a main memory. Such instructions may be transmitted by one or more transmission medium, including coaxial cables, copper wire and fiber optics, including the wires that comprise a system bus coupled to the processor. The memory of the controller54may also include a floppy disk, a flexible disk, hard disk, magnetic tape, other magnetic medium, a CD-ROM, DVD, other optical medium, etc. The controller54may be configured or equipped with other required computer hardware, such as a high-speed clock, requisite Analog-to-Digital (A/D) and/or Digital-to-Analog (D/A) circuitry, a necessary input/output circuitry and devices (I/O), as well as appropriate signal conditioning and/or buffer circuitry. Algorithms required by the controller54or accessible thereby may be stored in the memory58and automatically executed. The controller54may include an electrical current converter.

The vehicle system10further includes one or more temperature sensors56each configured to measure the temperature of one or more vehicle components11. Each of the temperature sensor56is in electronic communication with the controller54and is configured to generate a signal indicative of the temperature of the vehicle component11. For instance, the vehicle system10includes a first temperature sensor56acoupled to the catalytic converter42. As such, the first temperature sensor56ais configured to measure the temperature of the catalytic converter42and generate a signal indicative of the temperature of the catalytic converter42. Because the first temperature sensor56ais in electronic communication with the controller54, the first temperature sensor56ais configured to send this signal to the controller54. The controller54is therefore programmed to receive the signal from the first temperature sensor56aand determine the temperature of the catalytic converter42based on the signal received from the first temperature sensor54a.

The vehicle system10further includes a second temperature sensor56bcoupled to the turbocharger turbine housing34. As such, the second temperature sensor56bis configured to measure the temperature of the turbine32and generate a signal indicative of the temperature of the turbine32. Because the second temperature sensor56bis in electronic communication with the controller54, the second temperature sensor56bis configured to send this signal to the controller54. The controller54is therefore programmed to receive the signal from the second temperature sensor56band determine the temperature of the turbine32based on the signal received from the second temperature sensor56b.

The vehicle system10further includes a third temperature sensor56ccoupled to the exhaust manifold16, the first exhaust conduit38, and/or the bypass conduit46. As such, the third temperature sensor56cis configured to measure the temperature of the exhaust manifold16, the first exhaust conduit38, and/or the bypass conduit46and generate a signal indicative of the temperature of the exhaust manifold16, the first exhaust conduit38, and/or the bypass conduit46. Because the third temperature sensor56cis in electronic communication with the controller54, the third temperature sensor56cis configured to send this signal to the controller54. The controller54is therefore programmed to receive the signal from the third temperature sensor56cand determine the temperature of the exhaust manifold16, the first exhaust conduit38, and/or the bypass conduit46based on the signal received from the third temperature sensor56c.

The vehicle system10further includes one or more thermoelectric modules60coupled to one or more of the vehicle components11. The term “thermoelectric module” means: (a) a solid-state device that converts heat flux (i.e., temperature differences) directly into electrical energy through a phenomenon called the Seebeck effect; and (b) a solid-state active heat pump which transfers heat from one side of the pump to the other, with consumption of electrical energy, depending on the direction of the current, using the Peltier effect. Each of the thermoelectric modules60has a heating mode, a cooling mode, and a power-generation mode. When operated in the heating mode, the thermoelectric module60heats the vehicle component11(e.g., the catalytic converter42). When operated in the cooling mode, the thermoelectric module60cools the vehicle component11(e.g., the catalytic converter42). When operated in the power-generation mode, the thermoelectric module60converts a temperature gradient of the vehicle component11(e.g., the catalytic converter42) directly into electrical energy. To this end, each of the thermoelectric modules60is electrically connected to the onboard vehicle battery62of the vehicle system10. Therefore, when operating in the power-generation mode, each of the thermoelectric modules60is configured to supply electrical energy to the onboard vehicle battery62.

During operation, the controller54controls the operation of each of the thermoelectric modules60. To do so, the controller54may be coupled to the thermoelectric modules60via an actuator64. The controller54controls the operation of the actuator64. The actuator64may be configured, for example, to switch among the operating modes (i.e., the heating mode, the cooling mode, and the power-generation mode) of the thermoelectric modules60. As a non-limiting example, the actuator64may include a double-pole, double-throw (DPDT) switch to reverse the polarity of the electrical current supplied to the thermoelectric modules60. Reversing the polarity of the electrical current will result in reversed hot and cold sides of the thermoelectric modules60. Additionally, the actuator64may include current direction inverter to change the direction of the electrical current. In particular, the actuator64may change the current direction such that the thermoelectric module60operates in the power-generation mode, thereby supplying electrical energy to the onboard vehicle battery62.

In the depicted embodiment, the vehicle system10includes a first thermoelectric module60adirectly coupled to the catalytic converter42. Thus, the first thermoelectric module60ais in direct contact with the catalytic converter42to facilitate heat transfer between the first thermoelectric module60aand the catalytic converter42. During operation, when operated in the heating mode, the first thermoelectric module60aheats the catalytic converter42. When operated in the cooling mode, the first thermoelectric module60acools the catalytic converter42. When operated in the power-generation mode, the first thermoelectric module60aconverts a temperature gradient of the catalytic converter42directly into electrical energy.

The vehicle system10includes a second thermoelectric module60bdirectly coupled to the exhaust manifold16. Thus, the second thermoelectric module60bis in direct contact with the exhaust manifold16to facilitate heat transfer between the second thermoelectric module60band the exhaust manifold16. During operation, when operated in the heating mode, the second thermoelectric module60bheats the exhaust manifold16. When operated in the cooling mode, the second thermoelectric module60bcools the exhaust manifold16. When operated in the power-generation mode, the second thermoelectric module60bconverts a temperature gradient of the exhaust manifold16directly into electrical energy.

The vehicle system10includes a third thermoelectric module60cdirectly coupled to the turbocharger turbine housing34. Thus, the third thermoelectric module60cis in direct contact with the turbocharger turbine housing34to facilitate heat transfer between the third thermoelectric module60cand the turbocharger turbine housing34. During operation, when operated in the heating mode, the third thermoelectric module60cheats the turbocharger turbine housing34. When operated in the cooling mode, the third thermoelectric module60ccools the turbocharger turbine housing34. When operated in the power-generation mode, the third thermoelectric module60cconverts a temperature gradient of the turbocharger turbine housing34directly into electrical energy.

The vehicle system10includes a fourth thermoelectric module60ddirectly coupled to the bypass conduit46, the first exhaust conduit38, and/or the second exhaust conduit44. Thus, the fourth thermoelectric module60dis in direct contact with the bypass conduit46, the first exhaust conduit38, and/or the second exhaust conduit44to facilitate heat transfer. During operation, when operated in the heating mode, the fourth thermoelectric module60dheats the bypass conduit46, the first exhaust conduit38, and/or the second exhaust conduit44. When operated in the cooling mode, the fourth thermoelectric module60dcools the bypass conduit46, the first exhaust conduit38, and/or the second exhaust conduit44. When operated in the power-generation mode, the fourth thermoelectric module60dconverts a temperature gradient of the bypass conduit46, the first exhaust conduit38, and/or the second exhaust conduit44directly into electrical energy.

With reference toFIG. 2, the thermoelectric modules60employ the Peltier effect to create a heat flux74between the junction of two different types of materials. Thus, thermoelectric modules60are configured to transfer heat by applying a DC voltage to the sides of a semiconductor to create a temperature differential. In the depicted embodiment, each of the thermoelectric modules60is a solid-state heat pump that can transfer heat from one side of the thermoelectric modules60to the other, with consumption of electrical energy, depending on the direction of the current. The operation of the thermoelectric modules60may thus be changed between cooling and heating by changing the direction of the electric current. In summary, the thermoelectric modules60transfers heat upon receipt of electrical energy.

The thermoelectric modules60may include a plurality of n-type semiconductor elements66and p-type semiconductor elements68electrically connected in series but thermally connected in parallel. The n-type semiconductor elements66may be configured as pellets and may be wholly or partly made of n-type Bi2Te3, n-type PbTe, n-type CoSb3, n-type SiGe or another suitable material. The p-type semiconductor elements68may be configured as pellets and may be wholly or partly made of p-type Sb2Te3, a p-type PbTe, p-type CeFe4Sb12, p-type SiGe, TAGS, Yb14MnSb11, or another suitable material.

The thermoelectric modules60includes a first substrate70and a second substrate72both made of a material that is an electrical insulator but a good heat conduct. For example, the first substrate70and second substrate72may be wholly or partly made of ceramic. The n-type semiconductor elements66and p-type semiconductor elements68are disposed between the first substrate70and second substrate72. The first substrate70may be directly connected or mounted on one or more vehicle components11(e.g., the catalytic converter42). A plurality of electrical carriers90are mechanically coupled between the second substrate72and the n-type semiconductor elements66and p-type semiconductor elements68. These electrical carriers90are electrically connected to the onboard vehicle battery62. Another set of electrical carriers90is mechanically coupled between the first substrate70and the n-type semiconductor elements66and p-type semiconductor elements68. All the electrical carriers90are wholly or partly made of an electrically conductive material, such as a metal, and may be configured as electrically conductive tabs.

When DC voltage is applied to the thermoelectric module60with a direction from the p-type semiconductor elements66to the n-type semiconductor elements68, heat flux is created along with the movement of each p-type and n-type carrier (see heat flux74), thereby producing a thermal gradient along each semiconductor. This thermal gradient creates hot end at the substrate70and cold end at the second substrate72at the thermoelectric module60. The first substrate70thus becomes hot, and the second substrate72become cold. Because the first substrate70is thermally coupled to the vehicle component11(e.g., the catalytic converter42), the vehicle component11becomes hot when the first substrate70becomes hot. Reversing the polarity of the electrical current C, from the n-type semiconductor elements66to the p-type semiconductor elements68, will result in reversed hot and cold sides. Thus, the vehicle component11can become cold when the first substrate70becomes cold. As discussed above, the thermoelectric module60may additionally supply electrical energy to the onboard vehicle battery62by harvesting exhaust waste heat from the vehicle component11.

FIG. 3is a flowchart of a method100for operating the vehicle system10using the thermoelectric modules60. By executing the method100, the vehicle emissions are minimized by enhancing catalyst light-off and reducing cold start soot creation. Further, by utilizing the method100, the electric power generation is possible using waste heat from the after-treatment system40. Also, by utilizing the method100, the fuel economy of the vehicle system10is enhanced by reducing the need for enrichment. The method100may be executed by the controller54and begins at block102. At block102, the internal combustion engine12starts. Block102may represent a cold engine start. Then, the method100proceeds to block104. At block104, the controller54determines the temperature Tcompof the vehicle component11(e.g., the catalytic converter42) based on the signal received from the temperature sensor56(e.g., the first temperature sensor56a). In addition, at block104, the controller54determines whether the temperature Tcompof the vehicle component11(e.g., the catalytic converter42) is greater than a predetermined minimum temperature Tmin(e.g., the light-off temperature of the catalytic converter42). Each vehicle component11has a distinct predetermined minimum temperature Tmin, which is stored on the memory58of the controller54. It is desirable to maintain the temperature Tcompof the vehicle component11above the predetermined minimum temperature Tminto efficiently operate the vehicle components11. The predetermined minimum temperatures Tminare obtained by testing the vehicle components11. The predetermined minimum temperature Tminfor the catalytic converter42is the light-off temperature of the catalytic converter42. The term “light-off temperature” means the temperature at which catalytic reactions are initiated within a catalytic converter. If the temperature Tcompof the vehicle component11(e.g., the temperature of the catalytic converter42) is less than the predetermined minimum temperature Tmin(e.g., the light-off temperature of the catalytic converter42), then the method100proceeds to block106.

At block106, the controller54commands the thermoelectric module60to operate in its heating mode to heat the vehicle component11(e.g., the catalytic converter42) until the temperature Tcompof the vehicle component11(e.g., the temperature of the catalytic converter42) reaches the predetermined minimum temperature Tmin(e.g., the light-off temperature of the catalytic converter42). If the temperature Tcompof the vehicle component11(e.g., the temperature of the catalytic converter42) is greater than the predetermined minimum temperature Tmin(e.g., the light-off temperature of the catalytic converter42), then the method100proceeds to block108. At block108, the controller54determines whether the temperature Tcompof the vehicle component11(e.g., the catalytic converter42) is greater than a predetermined maximum temperature Tmax. Each vehicle component11has a distinct predetermined maximum temperature Tmax, which is stored on the memory58of the controller54. It is desirable to maintain the temperature Tcompof the vehicle component11below the predetermined maximum temperature Tmaxto protect the vehicle components11. The predetermined maximum temperatures Tmaxare obtained by testing the vehicle components11. If the temperature Tcompof the vehicle component11(e.g., the temperature of the catalytic converter42) is less than the predetermined maximum temperature Tmax, then the method100proceeds to block110.

At block110, the controller54commands the thermoelectric module60to operate in the power-generation mode. In the power-generation mode, the thermoelectric module60converts the temperature gradient of the vehicle component11directly into electrical energy. Further, in the power-generation mode, the thermoelectric module60supplies electrical energy to the onboard vehicle battery62. In other words, in the power-generation mode, thermoelectric module60supplies electrical energy to the onboard vehicle battery62by harvesting exhaust waste heat from the vehicle component11. If the temperature Tcompof the vehicle component11(e.g., the temperature of the catalytic converter42) is greater than the predetermined maximum temperature Tmax, then the method100proceeds to block112.

At block112, the controller54commands the thermoelectric module60to operate in its cooling mode to cool the vehicle component11(e.g., the catalytic converter42) until the temperature Tcompof the vehicle component11(e.g., the temperature of the catalytic converter42) is below the predetermined maximum temperature Tmaxin order to protect the vehicle component11.