# Patent

## Title
Thermoelectric heat pump

## Abstract

In certain embodiments, a thermoelectric heat pump includes a heat transfer region having an array of thermoelectric modules, a waste channel in substantial thermal communication with a high temperature portion of the heat transfer region, and a main channel in substantial thermal communication with a low temperature portion of the heat transfer region. An enclosure wall provides a barrier between fluid in the waste channel and fluid in the main channel throughout the interior of the thermoelectric heat pump. In some embodiments, the waste fluid channel and the main fluid channel are positioned and shaped such that differences in temperature between fluids disposed near opposite sides of the enclosure wall are substantially decreased or minimized at corresponding positions along the channels.

## Background
INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATION
Any and all applications for which a foreign or domestic priority claim is identified in the Application Data Sheet as filed with the present application are incorporated by reference and made a part of this specification.
BACKGROUND
Field
This disclosure relates to the field of thermoelectric devices and, in particular, to improved thermoelectric device enclosures and assemblies.
Description of Related Art
Certain thermoelectric (TE) devices, sometimes called Seebeck-Peltier devices, Peltier devices, thermoelectric engines, thermoelectric heat exchangers or thermoelectric heat pumps, employ the Peltier effect to transfer heat against the temperature gradient when an electric voltage is applied across certain types of materials, sometimes called thermoelectric materials or compounds. Examples of TE materials include, for example, doped PbTe, Bi2Te3, and other materials with a relatively high Seebeck coefficient. The Seebeck coefficient is a value that relates a temperature difference across a region of material with a corresponding electric potential difference across the region of material.
The efficiency of at least some TE devices can be improved by removing thermal energy from areas of a device where thermal energy accumulates due to, for example, the Peltier effect. Removal of such thermal energy can be accomplished, for example, by moving a waste fluid flow, such as air, across high temperature portions of TE materials or heat transfer structures attached to said high temperature portions. Furthermore, TE devices sometimes move a main fluid flow across low temperature portions of TE materials or heat transfer structures attached to said low temperature portions to remove heat from the main fluid flow. The main fluid flow may be used, for example, to cool enclosed spaces, materials, or equipment.
TE devices are typically housed in an enclosure that routes the fluid flows across a heat exchanger operatively coupled to the TE materials. Existing TE device enclosures and assemblies suffer from various drawbacks.
SUMMARY
Certain embodiments provide an assembly for a thermoelectric heat pump including: an enclosure with a plurality of substantially thermally isolated fluid channels formed therein; a first thermoelectric module operatively connected to the enclosure, the first thermoelectric module including a main junction and a waste junction; an elongate heat transfer member extending from at least one of the main junction and the waste junction of the first thermoelectric module into at least one of the plurality of fluid channels; at least one gap dividing the elongate heat transfer member into a plurality of heat transfer sections that are at least partially thermally isolated from adjacent heat transfer sections by the at least one gap, the at least one gap oriented such that fluid flows across the at least one gap as fluid flows through a fluid channel of the thermoelectric heat pump; and at least one bridge member extending across the at least one gap, the at least one bridge member connecting at least one of the plurality of heat transfer sections to a second heat transfer section.
The assembly can further include a second thermoelectric module operatively connected to the enclosure, the second thermoelectric module having a second main junction and a second waste junction. The first thermoelectric module and the second thermoelectric module can be arranged in substantially parallel planes, and the first and second thermoelectric modules can be oriented such that the waste junction of the first thermoelectric module and the second waste junction of the second thermoelectric module face towards one another. The elongate heat transfer member can extend from the waste junction of the first thermoelectric module to the second waste junction of the second thermoelectric module. Alternatively, the elongate heat transfer member can extend about half the distance from the waste junction of the first thermoelectric module to the second waste junction of the second thermoelectric module.
In some embodiments, the at least one bridge member is formed by removing portions of an elongate heat transfer member. The assembly can further include at least a second bridge member connecting the second heat transfer section to a third heat transfer section, wherein the at least one bridge member and the second bridge member are disposed at staggered positions along the at least one gap.
The assembly can have a heat transfer region including a plurality of rows, each of the plurality of rows including a plurality of thermoelectric modules. The plurality of fluid channels can include a waste fluid channel configured to be in substantial thermal communication with a high temperature portion of the heat transfer region and a main fluid channel configured to be in substantial thermal communication with a low temperature portion of the heat transfer region. A channel enclosure can provide a barrier between fluid in the waste fluid channel and fluid in the main fluid channel. The waste fluid channel and the main fluid channel can be positioned and shaped such that differences in temperature between fluids disposed near opposite sides of the channel enclosure are substantially minimized at corresponding positions along the channels.
Some additional embodiments provide a method of manufacturing a thermoelectric heat pump. The method can include providing an enclosure with a plurality of substantially thermally isolated fluid channels formed therein; operatively connecting a first thermoelectric module to the enclosure, the first thermoelectric module including a main junction and a waste junction; disposing an elongate heat transfer member within the enclosure, the elongate heat transfer member extending from at least one of the main junction and the waste junction of the first thermoelectric module into at least one of the plurality of fluid channels; providing at least one gap in the elongate heat transfer member, the at least one gap dividing the elongate heat transfer member into a plurality of heat transfer sections that are at least partially thermally isolated from adjacent heat transfer sections by the at least one gap, the at least one gap oriented such that fluid flows across the at least one gap as fluid flows through a fluid channel of the thermoelectric heat pump; and disposing at least one bridge member across the at least one gap, the at least one bridge member connecting at least one of the plurality of heat transfer sections to a second heat transfer section.
The method can further include operatively connecting a second thermoelectric module operatively connected to the enclosure, the second thermoelectric module having a second main junction and a second waste junction. In certain embodiments, the method includes arranging the first thermoelectric module and the second thermoelectric module in substantially parallel planes and orienting the first and second thermoelectric modules such that the waste junction of the first thermoelectric module and the second waste junction of the second thermoelectric module face towards one another. The method can also include disposing the elongate heat transfer member between the waste junction of the first thermoelectric module and the second waste junction of the second thermoelectric module. In some embodiments, the elongate heat transfer member is disposed such that the elongate heat transfer member extends about half the distance from the waste junction of the first thermoelectric module to the second waste junction of the second thermoelectric module.
The method can include forming the at least one bridge member by removing portions of the elongate heat transfer member. The at least one bridge member can join a plurality of separate heat transfer sections to form an elongate heat transfer member.
In certain embodiments, the method includes disposing at least a second bridge member between the second heat transfer section and a third heat transfer section. The at least one bridge member and the second bridge member can be disposed at staggered positions along the at least one gap.
Certain further embodiments provide a method of operating a thermoelectric heat pump. The method can include directing a fluid stream into at least one of a plurality of substantially thermally isolated fluid channels formed in an enclosure; directing the fluid stream toward a first thermoelectric module operatively connected to the enclosure, the first thermoelectric module including a main junction and a waste junction; directing the fluid stream across an elongate heat transfer member extending from at least one of the main junction and the waste junction of the first thermoelectric module into the at least one of the plurality of fluid channels; and directing the fluid stream across at least one gap dividing the elongate heat transfer member into a plurality of heat transfer sections that are at least partially thermally isolated from adjacent heat transfer sections by the at least one gap. At least one bridge member can be disposed across the at least one gap, the at least one bridge member connecting at least one of the plurality of heat transfer sections to a second heat transfer section.
Some embodiments provide an assembly for a thermoelectric heat pump including a heat transfer region including a plurality of rows, each of the plurality of rows including a plurality of thermoelectric modules, each of the thermoelectric modules including a high temperature junction and a low temperature junction; a waste fluid channel configured to be in substantial thermal communication with a high temperature portion of the heat transfer region; a main fluid channel configured to be in substantial thermal communication with a low temperature portion of the heat transfer region; and a channel enclosure providing a barrier between fluid in the waste fluid channel and fluid in the main fluid channel.
The waste fluid channel and the main fluid channel can be positioned and shaped such that differences in temperature between fluids disposed near opposite sides of the channel enclosure are substantially minimized at corresponding positions along the channels. The high temperature portion of the heat transfer region can include a first heat exchanger operatively connected to at least one high temperature junction of the plurality of thermoelectric modules. The first heat exchanger can include at least one gap dividing the heat exchanger into a plurality of heat transfer sections that are at least partially thermally isolated from adjacent heat transfer sections by the at least one gap, the at least one gap oriented such that fluid flows across the at least one gap as fluid flows through the waste fluid channel of the thermoelectric heat pump; and at least one bridge member extending across the at least one gap, the at least one bridge member connecting at least one of the plurality of heat transfer sections to a second heat transfer section.
The low temperature portion of the heat transfer region can include a second heat exchanger operatively connected to at least one low temperature junction of the plurality of thermoelectric modules. Thermal interface material can be disposed between the heat conducting fins and junctions of the plurality of thermoelectric modules. The first heat exchanger can include an arrangement of fins spaced at regular intervals. The arrangement of fins in the first heat exchanger can provide a different heat transfer capability than the second heat exchanger. The first heat exchanger can include at least one heat conducting fin that has a thickness greater than the thickness of heat conducting fins of the second heat exchanger.
The first heat exchanger can include at least one overhanging portion that protrudes past the at least one high temperature junction and the second heat exchanger includes at least one overhanging portion that protrudes past the at least one low temperature junction. The channel enclosure can include projections configured to nestle between the overhanging portions of the first heat exchanger and the overhanging portions of the second heat exchanger, the projections configured to contact the heat transfer region at boundaries between high temperature portions of the heat transfer region and low temperature portions of the heat transfer region such that leakage between the waste fluid channel and the main fluid channel at the junction between the channel enclosure and the heat transfer region is substantially minimized.
The channel enclosure can be constructed from a material system having at least a portion with a thermal conductivity not greater than approximately 0.1 W/(m×K). At least a portion of the material can include a foamed material, a composite structure, or a copolymer of polystyrene and polyphenylene oxide.
At least some portions of the channel enclosure adjacent to the heat transfer region can be bonded to the heat transfer region in substantially airtight engagement. A material selected from the group consisting of an adhesive, a sealant, a caulking agent, a gasket material, or a gel can be disposed between the channel enclosure and portions of the heat transfer region contacted by the channel enclosure. The material can include at least one of silicone or urethane.
The channel enclosure can include projections configured to contact the heat transfer region at boundaries between the high temperature portion of the heat transfer region and the low temperature portion of the heat transfer region such that leakage between the waste fluid channel and the main fluid channel at the junction between the channel enclosure and the heat transfer region is substantially minimized.
The assembly can include a first fan operatively connected to provide fluid flow in the waste fluid channel. A second fan can be operatively connected to provide fluid flow in the main fluid channel in a direction opposite the fluid flow in the waste channel.
A first row of thermoelectric modules can be electrically connected in parallel. A second row of thermoelectric modules can likewise be electrically connected in parallel. The first row and the second row can be electrically connected in series. One or more additional rows can have a plurality of thermoelectric modules electrically connected in parallel. The one or more additional rows can be electrically connected in series with one another, with the first row, and with the second row. The assembly can include a third row and a fourth row. Each row can include a plurality of thermoelectric modules electrically connected in parallel. In some embodiments, each of the plurality of rows includes four thermoelectric modules. The first row and the second row can be stacked close together.
The plurality of thermoelectric modules can be oriented such that a high temperature junction of a first thermoelectric module and a high temperature junction of a second thermoelectric module face towards one another. The first thermoelectric module and the second thermoelectric module can each contain an input terminal and an output terminal, the input terminal of the first thermoelectric module and the output terminal of the second thermoelectric module being disposed on a first side, and the output terminal of the first thermoelectric module and the input terminal of the second thermoelectric module being disposed on a second side.
In certain embodiments, the assembly is configured such that the thermoelectric heat pump continues to operate after one or more thermoelectric modules fails until each of the plurality of thermoelectric modules in a row fails.
The assembly can include at least one array connecting member configured to hold the plurality of rows together in a stack.
Each of the plurality of thermoelectric modules can include a first electric terminal and a second electric terminal. The assembly can include a conductor positioning apparatus having a first electrical conductor and a second electrical conductor disposed thereon. Positions of the first electrical conductor and the second electrical conductor can be fixed with respect to the conductor positioning apparatus. At least the first electrical conductor can be configured to electrically connect the first electric terminals of the thermoelectric modules in at least one of the plurality of rows to a first power supply terminal. At least the second electrical conductor can be configured to electrically connect the second electric terminals of the thermoelectric modules in at least one of the plurality of rows to at least one of a second power supply terminal or ground.
The conductor positioning apparatus can include an electrically insulating member. The first electrical conductor and the second electrical conductor can include electrically conductive traces deposited on the electrically insulating member.
The assembly can include a first clip positioned on a first end of the heat transfer region; a second clip positioned on a second end of the heat transfer region opposite the first end; and a bracket secured to the first clip and to the second clip, the bracket extending along a top side of the heat transfer region.
The first clip and the second clip have a shape configured to equalize forces applied across a length of the clip. In some embodiments, the first clip and the second clip are curved. The first clip and the second clip can include tabs configured to insert into slots formed in the bracket to provide secure engagement. The first clip and the second clip can include clip hooks, and the bracket can include bracket hooks. The clip hooks and bracket hooks can be configured to provide secure engagement when a rod is inserted between the clip hooks and the bracket hooks.
The heat transfer region can further include a plurality of elongate heat transfer members operatively connected to the plurality of thermoelectric modules. The bracket can include a spring element configured to allow a length of the bracket to stretch such that the bracket is configured to clamp the row of thermoelectric modules and the plurality of elongate heat transfer members in tight engagement. The spring element can include a depression formed at a position along the length of the bracket. In some embodiments, the spring element includes a shaped surface configured to flatten when tension is applied thereto.
The heat transfer region can further include a plurality of elongate heat transfer members operatively connected to the plurality of thermoelectric modules. The bracket can be configured to hold the row of thermoelectric modules and the plurality of elongate heat transfer members tightly together for at least ten years. The bracket can include a strip of fiberglass-reinforced tape. Thermal interface material can be disposed between the bracket and the thermoelectric modules.
In some embodiments, a plurality of ports for moving fluid into or out from the waste channel and the main channel are stacked in a first direction. In at least some of said embodiments, alternating high and low temperature portions of the heat transfer region are arranged in a second direction, where the second direction is substantially perpendicular to the first direction. In some embodiments, the high temperature portion of the heat transfer region includes a plurality of spatially separated high temperature regions. In some embodiments, the low temperature portion of the heat transfer region includes a plurality of spatially separated low temperature regions. In certain embodiments, thermoelectric modules are positioned and/or oriented to decrease or minimize the number of spatially separated high temperature regions and low temperature regions.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a perspective view of an embodiment of an apparatus for channeling air in a thermoelectric device.
FIG. 1B is a top view of the apparatus shown in FIG. 1A.
FIG. 1C is an end view of the apparatus shown in FIG. 1A.
FIG. 1D is a side view of the apparatus shown in FIG. 1A.
FIG. 1E is another end view of the apparatus shown in FIG. 1A.
FIG. 2A is a schematic diagram of an enclosure for a thermoelectric device incorporating the air channeling apparatus shown in FIG. 1A.
FIG. 2B is another view of the schematic diagram shown in FIG. 2A.
FIG. 3A is a perspective view of another embodiment of an apparatus for channeling air in a thermoelectric device.
FIG. 3B is a top view of the apparatus shown in FIG. 3A.
FIG. 3C is an end view of the apparatus shown in FIG. 3A.
FIG. 3D is a side view of the apparatus shown in FIG. 3A.
FIG. 3E is another end view of the apparatus shown in FIG. 3A.
FIG. 3F is a bottom view of the apparatus shown in FIG. 3A.
FIG. 4A is a schematic diagram of an enclosure for a thermoelectric device incorporating the air channeling apparatus shown in FIG. 3A.
FIG. 4B is another view of the schematic diagram shown in FIG. 4A.
FIG. 5 is a chart showing an example relationship between fluid temperature and position in a waste fluid channel of a thermoelectric device.
FIG. 6 is a chart showing an example relationship between fluid temperature and position in a main fluid channel of a thermoelectric device.
FIG. 7 is a perspective view of portions of an enclosure for a thermoelectric device.
FIG. 8A is a schematic diagram of heat transmitting members in a thermoelectric device.
FIG. 8B is another schematic diagram of heat transmitting members in a thermoelectric device.
FIG. 9A illustrates a clip used in some thermoelectric device enclosure embodiments.
FIG. 9B illustrates a thermoelectric module and heat transmitting members with clips.
FIG. 10 is a schematic diagram of an electrical network in a thermoelectric device.
FIG. 11 is a perspective view of an array of thermoelectric modules with wiring.
FIG. 12 is a perspective view of portions of a thermoelectric device enclosure.
FIG. 13 illustrates heat transmitting members attached to a thermoelectric module.
FIG. 14 is a schematic diagram showing segmented fins for use with a thermoelectric device.
FIGS. 15A-15B illustrate clips for use in some thermoelectric device embodiments.
FIGS. 16A-16B show configurations for a row of thermoelectric modules for use in some thermoelectric device embodiments.
FIGS. 17A-17B illustrate brackets for use in some thermoelectric device embodiments.
FIG. 18 illustrates a portion of a thermoelectric device.
FIG. 19A-19B show configurations for a row of thermoelectric modules for use in some thermoelectric device embodiments.
FIG. 20 illustrates a conductor positioning apparatus for use in some thermoelectric device embodiments.
FIG. 21 illustrates a conductor positioning apparatus for use in some thermoelectric device embodiments.
FIG. 22 illustrates an array of thermoelectric modules for use in some thermoelectric device embodiments.
FIGS. 23A-23B are views of a fluid channeling enclosure for use in some thermoelectric device embodiments.
FIG. 24 shows an array of thermoelectric modules installed in a fluid channeling enclosure.



DETAILED DESCRIPTION
A TE heat pump includes one or more TE modules that transfer heat against the thermal gradient from one junction (e.g., a low-temperature junction or main junction) to another (e.g., a high-temperature junction or waste junction). One or more suitable TE materials can be used for this purpose. A first defined channel provides a passageway for waste fluid flow, where the fluid is placed in substantial thermal communication with the high-temperature junction. Fluid flowing in the first defined channel can remove heat from the high-temperature junction. In some embodiments, the waste channel is in communication with a fluid reservoir (e.g., a reservoir in the external environment, such as the atmosphere) or other heat sink. Using a fluid to assist in removal of thermal energy from the high-temperature junction can improve the efficiency of a TE heat pump. The waste channel can be enclosed by any suitable structure, such as, for example, a material that has a low coefficient of thermal conductivity, such as foam, or a structure that provides substantial thermal isolation between the passageway defined by the waste channel and portions of the TE heat pump other than the high-temperature junction(s). A suitable device, such as, for example, a mechanical fan, can be operatively connected to move fluid through the waste channel.
In some embodiments, a TE heat pump includes a second defined channel that provides a passageway for a main fluid flow, where the fluid is placed in substantial thermal communication with the low-temperature junction. The low-temperature junction can be configured to remove heat from fluid flowing in the main channel. In certain embodiments, the main channel is in thermal communication with an area, a physical component, or other matter to be cooled by the TE heat pump. Like the waste channel, the main channel can be configured to provide substantial thermal isolation between the passageway defined by the main channel and portions of the TE heat pump other than the low-temperature junction(s). A suitable device can be operatively connected to move fluid through the main channel. In some embodiments, the direction of fluid movement in the main channel is generally opposite the direction of fluid movement in the waste channel (for example, creating a fluid flow system through the heat pump enclosure including counter-flow of fluids through the main and waste channels). In alternative embodiments, the direction of fluid movement in the waste channel and main channel is substantially the same (for example, creating parallel flow through the heat pump enclosure).
In some heat pump configurations, the main channel can be substantially adjacent to or in close proximity with the waste channel. In certain embodiments, it is advantageous to decrease or minimize heat transfer between fluid in the waste channel and fluid in the main channel.
In the embodiment shown in FIGS. 1A-1E, an apparatus 100 (sometimes called a channel enclosure, an air guide, or a guide) provides channels 108, 110 for fluid flow in a TE heat pump 200 (FIGS. 2A-2B). The guide 100 has a first side 102 configured to face away from TE material (e.g., towards equipment to be cooled or towards the outside environment) and a second side 104 configured to face towards TE material. The second side 104 can have projections 106, or slots to assist in secure or airtight engagement with heat transfer regions within the heat pump. The guide 100 defines a waste channel 108 that can diverge into one or more passageways 108a, 108b, 108c. The passageways of the waste channel 108 provide for thermal communication between the environment outside the TE heat pump 200 and regions of the heat pump in thermal communication with one or more high-temperature junctions of the TE materials. The guide 100 defines a main channel 110 that can also diverge into one or more passageways 110a, 110b. The passageways of the main channel 110 provide for thermal communication between the environment outside the TE heat pump 200 and regions of the heat pump in thermal communication with one or more low-temperature junctions of the TE materials.
The channels 108, 110 formed by the guide 100 shown in FIGS. 1A-1E are stacked in a vertical arrangement on the first side 102 of the apparatus. The channels 108, 110 are configured to move fluids such that they flow through TE materials separated into horizontally-arranged heat transfer regions. In some embodiments, the channels 108, 110 are shaped and positioned such that fluids flowing therethrough can reach the full geometric extent of associated heat transfer regions. For example, in the illustrated embodiment, the heat transfer region extends from the top edge 112 to the bottom edge 114 of the apparatus. Accordingly, the passageways of the channels 108, 110 on the second side 104 of the guide 100 also extend from top 112 to bottom 114. In other embodiments, heat transfer regions can have any arbitrary orientation with respect to the channels.
FIGS. 2A-2B show an enclosure for a TE heat pump 200 that includes a heat transfer region 202 positioned between a pair of the guides 100a-b illustrated in FIGS. 1A-1E. The heat pump 200 includes a waste channel 204 for a waste fluid flow that passes through high-temperature regions 208 of the heat transfer region 202. The waste fluid flow removes thermal energy from the heat pump 200 as it passes from a first end to a second end of the heat pump. One or more fans 212 can be used to provide movement of fluid from the first end, through the high-temperature heat transfer region 208, and to the second end, as indicated by the arrows shown adjacent to the waste channel 204 in FIGS. 2A-2B. Alternatively, the fans 212 can be used to move the waste fluid flow from the second end to the first end. As used in this disclosure, the term “fan” broadly refers to any suitable device for moving air or other fluids, including, without limitation, an oscillating fan, a blower, a centrifugal fan, a motorized fan, a motorized impeller, a turbine, or a mechanical device configured to move fluids through a channel. In some embodiments, the TE heat pump includes redundant fans. The fans can be wired in parallel or in series with one another.
The heat pump 200 also includes a main channel 206 for a main fluid flow that passes through low-temperature regions 210 of the heat transfer region 202. The heat pump 200 removes thermal energy from the main fluid flow as it passes from the second end to the first end. One or more fans 214 can be used to move fluid from the second end, through the low-temperature heat transfer region 210, and to the first end, as indicated by the arrows shown adjacent to the main channel 206 in FIGS. 2A-2B. Alternatively, the fans 214 can be used to move the main fluid flow from the first end to the second end. In the illustrated embodiment, the path of the main fluid flow can be substantially parallel to the path of the waste fluid flow or substantially opposite the path of the waste fluid flow (for example, in a counter-flow arrangement).
The heat pump 200 can include an array of thermoelectric modules (TE modules) within the heat transfer region 202. For example, the device may contain between four and sixteen thermoelectric modules or another suitable number of modules, such as a number of modules appropriate for the application for which the heat pump 200 is intended. A door or panel (not shown) in the case of the heat pump can provide access to the internal components of the heat pump, including, for example, the air channels 204, 206, the fans 212, 214, and/or the TE modules.
One or more fans can be used to push or pull air through the device from a vent in an end of the device, for example. For example, the fans can pull or push air through the device from a first end and/or a second opposite end. As used in the context of fluid flow, the term “pull” broadly refers to the action of directing a fluid generally from outside the device to inside the device. The term “push” broadly refers to the action of directing a fluid generally from inside the device to outside the device. The fans can be positioned within a fan enclosure or another suitable housing. A channel enclosure or air guide 100 can be seated beneath the fan enclosure.
In some embodiments, the main side of the device 200 (for example, the side associated with the main fans 214) can be inserted into an enclosure, for example, in order to cool the interior of the enclosure. In some embodiments, the waste side of the device 200 (for example, the side associated with the waste fans 212) is exposed to the ambient air, a heat sink, a waste fluid reservoir, and/or a suitable region for expelling a waste fluid flow. In certain embodiments, waste fluid flow is prevented from entering the main channel. For example, the exhaust of the waste channel can be separated from the intake of the main channel by a wall, a barrier, or another suitable fluid separator.
In various embodiments described herein, fans can be configured to pull or push air through a TE device, and fans can be mounted in various positions in the TE device. The flow patterns inside the TE device can include substantially parallel flow, counter flow (e.g., flow in substantially opposite directions), cross flow (e.g., flow in substantially perpendicular directions), and/or other types of flow depending upon, for example, the fan direction and/or the position(s) in the TE device where the fans are mounted. In some embodiments, a TE device includes one or more waste fans for directing fluid flow through a waste channel and one or more main fans for directing fluid flow through a main channel. In certain embodiments, fans are positioned on the same end or on different ends of a device, where the end refers to a portion of the device on one side of a TE module. The following are example configurations and corresponding flow patterns:

    
    
        1. Waste fan pushes, main fan pushes, waste and main fans on same end—fluid flow system includes substantially parallel flow
        2. Waste fan pushes, main fan pushes, waste and main fans on different ends—fluid flow system includes substantially counter flow
        3. Waste fan pulls, main fan pulls, waste and main fans on same end—fluid flow system includes substantially parallel flow
        4. Waste fan pulls, main fan pulls, waste and main fans on different ends—fluid flow system includes substantially counter flow
        5. Waste fan pushes, main fan pulls, waste and main fans on same end—fluid flow system includes substantially counter flow
        6. Waste fan pushes, main fan pulls, waste and main fans on different ends—fluid flow system includes substantially parallel flow
        7. Waste fan pulls, main fan pushes, waste and main fans on same end—fluid flow system includes substantially counter flow
        8. Waste fan pulls, main fan pushes, waste and main fans on different ends—fluid flow system includes substantially parallel flow
    
    


In another embodiment shown in FIGS. 3A-3F, a guide 300 provides channels 308, 310 for fluid flow in a TE heat pump 400 (FIGS. 4A-4B). The guide 300 is similar to the guide 100 shown in FIGS. 1A-1E, except that the main channel 310 of the guide 300 includes an aperture 311 on the bottom surface 314 that allows fluid in the main channel 310 to enter or exit through the bottom of the heat pump 400.
As shown in FIGS. 4A-4B, the heat pump 400 can be housed in an enclosure 420 that is configured to allow ingress and egress of fluid through a bottom portion 422 of the heat pump. For example, fans 414 that move fluid through the main channel 406 can be situated in a plane substantially perpendicular to the plane in which fans 412 that direct fluid through the waste channel 404 are located. A fluid port 416 for the main channel 406 can also be at least partially positioned on the bottom of a main side 422 of the enclosure 420.
In some embodiments, fans 414 pull air in through the main side 422 of a heat pump 400 and direct the air into the main side channels, through main side heat exchanger fins (not shown), and the air exits at the opposite end through the port 416 of the main side 422. In some embodiments, fans 412 are mounted at the case surface of the waste side. The waste fans and/or the main fans can be mounted next to the housing wall. Fans can also be mounted adjacent to air holes or vents, such as, for example, port 416.
FIG. 12 shows a perspective view of certain assembled internal components 1200 of a TE heat pump. The heat pump assembled components include foam channels 1202, 1204 and an array of TE modules 1206 positioned within the foam channels. In some embodiments, the array 1206 transfers thermal energy away from a main fluid flow (for example, air flowing through a main fluid channel 110) and into a waste fluid flow (for example, air flowing through a waste fluid channel 108). In some embodiments, the main fluid flow is directed into the array 1206 by the foam channels 1202 on a first end of the heat pump 1200 and out of heat pump via the foam channels 1204 on a second opposite end of the heat pump. The waste fluid flow can be directed in the same way or directed into the array 1206 by the foam channels 1204 on the second end and out of the heat pump 1200 via the foam channels 1202 on the first end.
FIG. 5 and FIG. 6 show example temperature variations within the main and waste fluid channels of some heat pump configurations described herein. In some embodiments, temperature differences between fluid channels (such as, for example, between a waste channel 204 and a main channel 206, as shown in FIGS. 2A-B) is substantially decreased or minimized during operation of a TE heat pump. FIG. 5 shows an example relationship between fluid temperature and position in a waste fluid channel of a thermoelectric device. FIG. 6 shows an example relationship between fluid temperature and position in a main fluid channel of a thermoelectric device. The waste fluid channel, for example, may include fluid in positions that are adjacent to or near corresponding fluid positions in the main fluid channel. For example, corresponding positions can include positions of fluid disposed near opposite sides of an enclosure wall or thermoelectric module that separates the waste fluid channel from the main fluid channel. These portions of the fluid flow in the waste and main fluid channels can be said to be at “corresponding positions” within the heat pump.
In some embodiments associated with the information shown in FIG. 5 and FIG. 6, the direction of fluid flow in the waste channel is substantially opposite the direction of fluid flow in the main fluid channel. Accordingly, changes in fluid temperatures at corresponding positions along the length of the heat pump are typically in the same direction, although the temperature magnitudes and temperature change magnitudes may vary between the channels. By maintaining fluid flow in substantially opposite directions, the heat pump is configured to decrease or minimize temperature differences between the fluids in the channels along the length of the heat pump and/or at ends of the heat pump. In some embodiments, the thermal gradient between the channels along the length of the heat pump is decreased and thermal isolation of the fluids in the channels is improved by fluid flow characteristics.
Assemblies of TE modules can be stacked one on top of another to make a line of TE module assemblies when more than one TE module is used. Multiple TE modules may be used, for example, in order for a TE device to provide adequate cooling power for an enclosure, a piece of equipment, or some other space. In some embodiments, an array of TE module assemblies including multiple rows of TE module assemblies can be used to provide increased cooling power in a TE device. The channel enclosures disclosed herein can be used to route air or other fluids through the main side (for example, the side of the TE device that cools air) and the waste side (for example, the side that exhausts heated air). In some embodiments, a channel enclosure keeps the two air flows (for example, the main air flow and the waste air flow) from mixing.
FIGS. 23A-B show perspective views of a top side 2302 of a channel enclosure 2300 and a bottom side 2304 of the enclosure 2300. The illustrated enclosure includes passageways configured to suitably route fluid flows through an array of thermoelectric modules when the channel enclosure 2300 is operatively connected within a TE device. The channel enclosure can be made from any suitable material, including, for example, an insulating material, a foamed material, Gset® (a material available from Fagerdala World Foams AB of Gustaysberg, Sweden), a composite material, a copolymer of polystyrene and polyphenylene oxide, or a combination of materials. In certain embodiments, the thermal conductivity of the material from which the channel enclosure is made does not exceed about 0.03 W/K. In some embodiments, an injection molding machine is used to fabricate the channel enclosure 2300.
In the embodiment shown in FIG. 7, a channel enclosure 702 divides a main fluid stream flowing on the main side of a TE device 700 into streams (or flows) that travel through multiple passageways 704a-c. The passageways 704a-c direct the flows across main heat transfer members 706a-d (e.g., cooled fins) operatively connected within an array of TE module assemblies. The main heat transfer members 706a-d are operatively connected to main sides of respective TE modules 708a-d. In some embodiments, the channel enclosure provides passageways 710a-b on the waste side that similarly direct a waste fluid stream across waste heat transfer members 712a-d (e.g., heated fins). The waste heat transfer members 712a-d are operatively connected to waste sides of the TE modules 708a-d. In some embodiments, the heat transfer members 706, 712 overhang the TE modules 708 to some extent along the sides of the TE module assemblies (e.g., at junctions between the TE module assemblies and the channel enclosure 702).
In certain embodiments, the main fluid stream and the waste fluid stream are separated physically and thermally by the channel enclosure 702. The channel enclosure 702 can be made from a suitable thermal insulator, such as, for example, foam, a multi-layer insulator, aerogel, a material with low thermal conductivity (e.g., a material with thermal conductivity not greater than 0.1 W/(m×K)), another suitable material, or a combination of suitable materials. In some embodiments, the channel enclosure 702 includes projections 714 that separate the waste and main flows at junctions between the channel enclosure 702 and the TE module assemblies. In certain embodiments, one or more of the projections 714 has a feature 716 at its end that nestles between heat exchanger fins 706, 712 that overhang the TE modules 708. In some embodiments, the feature 716 includes a trapezoidal (or other suitably shaped) section of foam or another suitable material that is between about six and about eight millimeters in width. A sealant, such as, for example, caulking, gel, silicone, or urethane can be carefully applied to portions of the channel enclosure 702 that contact the TE modules 708.
In the embodiment shown in FIG. 7, the heat transfer members 706, 712 are divided into segments 802a-d separated by gaps 804a-c. The gaps 804a-c extend in a direction substantially perpendicular to the direction of fluid flow through the passageways 704, 710. The segments 802a-d decrease thermal energy transfer within the heat transfer members 706, 712 along a path extending from one end of the TE device to the other end of the device. In some embodiments, the TE device includes heat transfer members 706, 712 having a plurality of separated fin sections 802 operatively connected to each side of the thermoelectric modules 708. Any suitable number of fin sections 802 can be used, including more than two sections, four sections, or between two and ten sections. The heat transfer members can be installed by, for example, attaching the fins 802 to the TE modules 708 manually, attaching the fins using a machine, and/or attaching the fins to the modules 708 with a thermal interface material. Thermal interface materials (or thermally conductive materials) include, without limitation, adhesive, glue, thermal grease, phase change material, solid material, foil, solder, soft metal, graphite, liquid metal, or any other suitable interface material.
In some embodiments, the heat transfer members 706, 712 are secured in place using a thermally conductive grease to achieve good thermal contact with the module 708 surface. In some embodiments (e.g., when the fins of heat transfer members 706, 712 are divided into multiple fin sections 802), certain steps may be taken to ensure that the fin sections 802 remain in fixed relative positions with respect to one another. For example, in certain embodiments, the fin sections 802 of each fin are made in one piece (as discussed in more detail below), and the fins can be clamped together and attached to the modules 708 using grease.
In certain embodiments, the efficiency of the TE device 700 is improved when thermal isolation in the direction of flow is increased. Using heat transfer members 706, 712 divided into multiple segments 802 can increase the thermal isolation within the heat transfer members 706. In some embodiments, using heat transfer members 706, 712 made of high thermal conductivity material (e.g., Al or Cu) without multiple segments 802 can cause the heat transfer member 706, 712 to have little thermal isolation in the direction of fluid flow.
FIGS. 8A-8B illustrate a one-piece main fin 800a and a one-piece waste fin 800b, respectively, configured for attachment to a thermoelectric module 708. In the illustrated embodiments, the fins 800 are configured to create thermal isolation in the direction of fluid flow. The fins 800 are separated into segments 802a-d by a plurality of gaps 804 (or slits). One-piece fin construction is achieved by having the fin sections 802 connected tenuously by narrow bridges 806 along the length of the material. In some embodiments, the bridges 806 are sufficiently narrow to maintain minimal thermal conductivity in the direction of flow. For example, in certain embodiments, the bridges 806 are less than ten millimeters in width, less than two millimeters in width, about one millimeter in width, or not more than about one millimeter in width. In certain embodiments, the bridges 806 occur at arbitrary locations along the fin segments 802. In some embodiments, there are a sufficient number of bridges 806 between fin segments 802 such that the fin 800 handles substantially the same as a unitary fin 800 without segments when the fin 800 is folded up. For example, the bridges 806 may be spaced at various intervals 808, including intervals of more than ten millimeters, less than thirty millimeters, about twenty millimeters, more than ten times the width of the bridges 806, more than fifteen times the width of the bridges 806, about twenty times the width of the bridges 806, or another suitable interval. In some embodiments, the interval 808a between bridges 806 on a main fin 800a differs from the interval 808b between bridges 806 on a waste fin 800b. 
In some embodiments, the positioning of the bridges 806 is designed to stiffen the structure of the fins 800. For example, in certain embodiments, the positions of the bridges 806 along the segments 802 are staggered at an interval 810 so that they do not line up with one another through the width of the fins 800. In some embodiments, the stagger interval 810a in the position of bridges 806 on a main fin 800a differs from the stagger interval 810b in the position of bridges 806 on a waste fin 800b. 
FIG. 9A illustrates a clip 900 that can form part of a thermoelectric module assembly. The clip 900 includes a base 908 from which two or more legs 906a-b extend in a generally perpendicular orientation with respect to the base 908. The legs 906 can have equal lengths or different lengths, depending on the configuration of the assembly. Multiple curved hooks 902a-b, 904 extend out from the legs 906a-b. In some embodiments, the base 908 of the clip 900 is curved. For example, the base 908 can be shaped such that, when the legs 906a-b are pulled in a direction away from the base 908 (for example, when the hooks 902a-b, 904 are attached to an object that puts tension the clip 900), the force generated by the clip on a thermoelectric module assembly is uniform across the surface of the base 908. In some embodiments, the base 908 has a parabolic shape, and attaching the clip 900 to an assembly adds forces to the clip 900 that cause the base 908 to flatten.
The thermoelectric module assembly 950 shown in FIG. 9B includes two identical clips 900a-b that have hooks 902a-b, 904a-c extending towards one another from the base 908 of each clip 900a-b. A pin 910 is inserted between curved portions of the hooks 902, 904 such that the hooks are held together tightly. The clips 900a-b encase a thermoelectric material 952 that is attached to fins 954. The fins 954 transfer thermal energy to and from the thermoelectric material 952. The shape of the clips 900a-b can be such that the distribution of force is even across the length of the clip at contact points between the clip and a TE module.
FIG. 10 is a schematic diagram of an array 1000 of thermoelectric modules. In the illustrated embodiment, four rows 1002a-d of four thermoelectric modules each are operatively connected to form an array 1000 of sixteen thermoelectric modules. Each row includes a plurality of thermoelectric modules connected in parallel between a row input 1004 and a row output 1006. Each row output 1006 is connected in series with another row input 1004, except that the first input 1004a and the last output 1006d are connected to a power supply. This electrical topology can be called a “series-parallel” arrangement of thermoelectric modules. In some embodiments, a heat pump employing a series-parallel array 1000 of thermoelectric modules can continue to operate after one or more modules within the array 1000 fail. For example, the heat pump can be configured to continue operation until all of the modules in at least one row fail.
FIG. 11 illustrates a mechanical wiring arrangement for an array 1100 of modules in some embodiments. While the illustrated array 1100 includes twelve modules in three rows 1002a-c, any suitable number of modules and rows 1002 of modules can be incorporated into the array 1100. For example, in some embodiments, a TE heat pump includes an array with six, eight, twelve, sixteen, between four and fifty, or a number of modules suitable to cool a target piece of equipment with acceptable performance.
FIG. 13 illustrates an individual thermoelectric module 1300. The module 1300 includes heat exchangers (or fins) 1310, 1312 positioned on opposite sides of thermoelectric material 1304. In some embodiments, the configuration of the fins 1310 connected to the main side (or low temperature side) of the thermoelectric material 1304 differs from the configuration of the fins 1312 connected to the waste side (or high temperature side) of the thermoelectric material 1304. For example, the main fins 1310 can be shorter and more densely packed than the waste fins 1312. Some or all module assemblies 1300 in a thermoelectric module array can be configured in this way. Providing longer and less densely packed waste fins 1312 can allow greater fluid flow through the waste side of the TE module.
In some embodiments, heat is pumped from one side to the other by the action of the TE module when electricity is applied to the module. The conductive materials within the module have a non-zero electrical resistivity, and the passage of electricity through them generates heat via Joule heating. In some embodiments, the main side is cooled by pumping heat from the main side to the waste side. Joule heating within the module generates heat that is passed to the main side and the waste side. For example, half of the Joule heating may go to the waste side and half to the main side. Consequentially, the heat being added to the waste heat exchange fluid can be greater than the heat being removed from the main side heat exchange fluid. In some embodiments, creating larger fluid flow on the waste side than on the main, for example, by providing waste side fins that are bigger and less dense than main side fins, can allow higher flow rate on the waste side without excessive restriction of waste fluid flow.
In the embodiment shown in FIG. 13, the heat exchangers 1310, 1312 include four fin segments. This can help achieve performance improvements, such as improvements discussed in U.S. Pat. No. 6,539,725, the entire contents of which are incorporated by reference herein and made a part of this specification. The fins 1310, 1312 can be glued onto the surface of the thermoelectric material 1304 or attached in another suitable way. In the illustrated embodiment, the fins 1310, 1312 extend beyond the edges of the thermoelectric material 1304 in the direction of flow. The extensions can allow an insulating material to be positioned between the fins, which can help prevent the hot (for example, waste) and cold (for example, main) fluid streams from mixing. The module assembly 1300 can be wrapped with tape 1308. The tape 1308 can help protect the fins 1310, 1312 from being bent and can electrically insulate the fins 1310, 1312 from electrical elements (for example, wires 1306a-b) that might otherwise contact them.
Returning to FIG. 11, illustrated are wires 1102, 1104, 1106, 1110 used to connect the modules within the array 1100 together electrically. Each row 1002a-c is wired in a series circuit to other rows via a conductor 1110, and modules within a row 1002 are connected in a parallel circuit to other modules within the row 1002 via conductors 1102, 1104, 1106. In some embodiments, the wires 1102, 1104, 1106, 1110 are thin and uninsulated, and an insulator (for example, tape) is disposed between the wires and the modules to prevent shorting out the wires to the fins. In some embodiments, the modules that are next to each other in a row 1002 are arranged so that adjacent modules have main sides facing one another or have waste sides facing one another. This arrangement can decrease or minimize the number of channels for which a channel enclosure (for example, the channel enclosure shown in FIG. 1A or FIG. 3A) provides ducting. In the embodiment shown in FIG. 11, the main fins are shown tightly spaced, and the waste fins have a wider spacing. The spacing of the fins can facilitate various heat transfer capabilities. Other features of the fins can also be used to affect fin heat transfer capability, such as, for example, different shape, material, lengths, etc. In some embodiments, corresponding contacts 1108 for the module wiring alternates sides along the length of the row 1002. For example, the modules within a row 1002 may be alternately rotated to achieve the simpler ducting arrangement. In some embodiments, the wiring within a row 1002 includes module wires 1104a-b that are bent over across another wire to reach the appropriate terminal 1108. The wiring arrangement also includes module wires 1106a-b that do not cross another wire to reach the appropriate terminal 1108. In some embodiments, the module wires 1104, 1106 are insulated to prevent shorting to other wires.
In some embodiments, the rows 1002a-c of modules are configured to be stacked close together in a vertical direction. For example, the wires 1102a-b can be substantially thin or ribbon-like to facilitate close stacking of module rows. The rows 1002a-c shown in FIG. 11 are separated by exaggerated gaps in to show the wiring configuration between rows.
In some embodiments, a method of assembling TE modules includes taping flat copper conducting strips across a row of TE modules held together by tape. Module wires can be attached to the copper strips by bending them over the strips, cutting the wires, stripping the wires, and soldering the wires to the flat copper strips. Additional rows of TE modules can be similarly assembled and stacked together. The array can be held together by taping the array around its periphery.
In some embodiments, when the rows 1002a-c are stacked on top of one another, the surfaces of the heat exchangers do not actually touch. Instead, they can be separated by the thickness of the wire insulation of the module wires 1104a-b that are bent over to be attached (for example, soldered) to the metal strips or contacts 1108. In some embodiments, these separations create leak paths by which fluid can pass through the array of modules without being heated or cooled. Furthermore, the air paths can also leak from one side of the heat pump to the other (for example, from one air channel to another). In some embodiments, the cracks are filled with a sealing agent such as, for example, silicone rubber sealant, caulk, resin, or another suitable material.
Some embodiments provide an assembly that substantially eliminates leak paths without the use of sealing agents. In addition, some embodiments provide a method of assembling two dimensional arrays of TE module assemblies with improved consistency and dimensional control. Some embodiments provide a TE device assembly with robust mechanical strength and integrity. Some embodiments reduce the likelihood of damage to heat exchange members within module assemblies and reduce the likelihood of wiring errors while manufacturing module assemblies.
In further embodiments, a method of assembling an array of TE modules includes providing one-piece segmented fins having narrow connecting tabs between adjacent fin sections. Thermal interface material can be applied between the fins and TE materials. The fins can be secured to the TE materials using clips, such as, for example, the clip 900 shown in FIGS. 9A-B. In some embodiments, the clips include legs having asymmetric lengths. In some embodiments, the leg lengths are adjustable using a forming tool. The clips can be held together with a suitable attachment device, such as, for example, hooks and pins or tabs and slots. The clips can be used to hold together a row of TE modules. A bracket, which can include hooks and/or slots, can be used to span the length of a row between the clips. Module wires can include short solid conductors.
Array assemblies can include two kinds of TE modules, having different starting pellet polarity. The modules can include identifying marks for distinguishing between the different kinds. The identifying marks can include, such as, for example, different module wire colors or another distinguishing feature. A printed circuit board (PCB) can be positioned beside each row of modules and can provide electrical conductors for supplying power to the modules. Wires (such as, for example, substantially thin or flat wires) soldered to PCB pads can provide connections between rows of modules. Other wires can be soldered to PCB holes to connect a power supply to the array of modules. In some embodiments, the channel enclosure includes a recess, an aperture, or a cavity that provides a space for power supply lead wires to be connected to the array of modules.
FIG. 14 illustrates a perspective view of a main side heat exchanger 1400. The heat exchanger 1400 is separated into four fin sections 1402a-d by gaps 1404a-c between the fin sections. The fin sections are connected by bridges 1406 that are disposed every sixth fin 1408 between adjacent fin sections (for example, fin sections 1402c and 1402d). The bridges can be staggered between rows of fin sections by two fins or by another suitable number of fins. The heat exchanger 1400 can be constructed from any suitable material, such as, for example, annealed aluminum, tempered aluminum, or a material with high thermal conductivity. The heat exchanger 1400 can be constructed from a material of suitable thickness, such as, for example, material that is about 0.25 mm thick. The heat exchanger 1400 can include a suitable number of fins 1408, such as, for example, fifty fins or between twenty and one hundred fins, and can be configured to compress and/or expand in at least one dimension. In some embodiments, the heat exchanger 1400 is at least about 40 mm in length when the heat exchanger is in a compressed condition. The heat exchanger 1400 can include fins 1408 of any suitable height, such as, for example, about 21 mm, and fins 1408 of any suitable flow length, such as, for example, about 10 mm. In some embodiments, the heat exchanger 1400 has a total flow length of at least about 40 mm.
In certain embodiments, at least some heat exchangers in a row of TE modules are approximately twice as wide as other heat exchangers. For example, some heat exchangers can extend from a surface of a first TE module to an opposite surface of a second adjacent TE module in the same row. Heat exchangers positioned at the ends of the row can be narrower. In other embodiments, all heat exchangers in a row of TE modules are substantially the same width. In further embodiments, waste heat exchangers and main heat exchangers have different widths.
FIG. 15A shows an embodiment of a clip 1500 that includes a base 1502 with asymmetric legs 1504, 1506 extending generally perpendicularly therefrom. The lengths of the legs 1504, 1506 can be adjusted using a forming tool such that the clip 1500 can securely engage a row of TE modules. In the illustrated embodiment, the legs have a plurality of hooks 1508 extending away from the base. The hooks 1508 can be curved or have any other suitable shape and can be configured to securely engage a bracket with hooks and a pin inserted therebetween (for example, the bracket 1700 shown in FIG. 17A).
FIG. 15B shows an alternative embodiment of a clip 1550 that includes a base 1552 with asymmetric legs 1554, 1556 extending therefrom. The longer leg 1554 includes a narrowed portion with tabs 1558 extending away from the base 1552. The shorter leg 1556 also has tabs 1558 configured to securely engage slots (for example, the slots 1758 in the bracket 1750 shown in FIG. 17B).
FIG. 16A shows a row 1600 of TE modules 1608 assembled with at least one bracket 1602 connecting a pair of clips 1604, 1606. The bracket and clips hold the TE modules 1608 within the row 1600 together. Matching sets of bracket hooks 1610 and clip hooks 1612 can form a secure connection between the bracket 1602 and clips 1604, 1606 when a securing pin (not shown) is inserted through the hooks 1610, 1612. In an alternative embodiment, the rows are held together with rigid tape (for example, fiberglass-reinforced tape) that is designed to stretch at most minimally over long periods of time. In such alternative embodiments, the rigid tape can replace the brackets 1602. In some embodiments, the clips and brackets are constructed from a suitable material, such as, for example, metal, 300 series stainless steel, spring temper material, carbon steel, beryllium copper, beryllium nickel, or a combination of materials.
FIG. 16B shows a row 1650 of TE modules 1658 assembled with a least one bracket 1652 connecting a pair of clips 1654, 1656. The clips 1654, 1656 have tabs that securely engage slots 1660 formed in the bracket 1652.
FIG. 17A illustrates a bracket 1700 having a base 1702 from which hooks 1704, 1706 extend on opposite ends of the base 1702. The hooks 1704, 1706 can be separated by gaps to allow matching clip hooks to be inserted therebetween. The bracket has a length proportional to the length of a row of TE modules which it is designed to secure. In some embodiments, the bracket 1700 includes a spring element (not shown), such as, for example, a dip or U-shaped feature positioned along the base 1702. The spring element allows the length of the bracket 1700 to extend a small distance to allow the bracket 1700 to tightly clamp TE module surfaces and fins together. Along with thermal interface material disposed in areas between module surfaces and fins, tight clamping can provide increased contact and thermal conductivity between TE module surfaces and the fins.
FIG. 17B illustrates a bracket 1750 having a base 1752 and raised portions 1754, 1756 at opposite ends of the base 1752. The raised portions 1754, 1756 can be positioned to allow a clip positioned beneath the raised portion to be substantially flush with the base 1752 of the bracket 1750 when the clip and bracket are used in a TE module row assembly. The raised portions 1754, 1756 have slots 1758 formed therein. The slots 1758 are configured to engage matching tabs extending from clips.
FIG. 18 illustrates a row 1800 having a single TE module 1802. The TE module 1802 is secured on its respective ends by a first clip 1806 and a second clip 1804 having unequal-length legs. The clips 1804, 1806 are connected to one another by a bracket 1808. The bracket 1808 is sized to accommodate a row with only one TE module 1802.
FIG. 19A shows a row 1900 of TE modules 1902 secured together by clips 1906 and brackets 1908. A printed circuit board 1904 (PCB) is positioned alongside the row 1900 on top of a bracket 1908. In some embodiments, the PCB 1904 is configured to provide conductors that supply power to the TE modules 1902 in the row 1900. The PCB 1904 includes openings 1910 that provide clearance for connecting hooks 1914 that extend into the plane of the PCB 1904. The PCB 1904 also includes apertures 1912 that provide clearance for TE module 1902 power terminals.
FIG. 19B shows a row 1950 of TE modules 1952 secured together by clips 1956 and brackets 1958. A PCB 1954 disposed on top of a bracket 1958 includes openings 1960 that provide clearance for tabs and slot portions of the bracket 1958 that extend into the plane of the PCB 1954.
FIG. 20 shows a top side of a PCB 2000 that includes certain features for operatively connecting to a row of TE modules. The PCB 2000 includes a body portion 2002 that has apertures 2004 formed therein. The apertures 2004 are positioned to approximately align with TE module power terminals when the PCB 2000 is positioned alongside a row of TE modules. The apertures provide spaces for module wiring. Apertures at the ends of the PCB 2000 can provide spaces for lead wires from an array power supply. The PCB 2000 includes openings 2006 configured to accommodate protrusions from the underlying TE module row assembly. Examples of protrusions include connecting hooks and/or tabs. The PCB 2000 can also include row tabs 2008 disposed at ends of the PCB 2000. The row tabs 2008 can be configured to engage side pieces that register rows (for example, providing regular row spacing) with respect to one another.
FIG. 21 shows a bottom side of the PCB 2000 shown in FIG. 20. The PCB 2000 includes a first trace 2100 and a second trace 2102 disposed along sides of the PCB 2000. The traces can be wide enough to solder flat wires at ends 2104 of the PCB 2000 for electrically connecting rows of modules together. Solder dams can be made in the traces around apertures 2004 in the PCB to facility soldering. In some embodiments, the traces 2100, 2102 are made from copper. Any suitable amount of conductor material can be used, such as, for example, about two ounces of copper. In some embodiments, the PCB 2000 is single-sided (for example, the PCB has traces on only one side) and has no plated-through holes. In other embodiments, the PCB 2000 is double-sided and includes plated-through holes. In some embodiments, the number of PCBs 2000 and rows of TE modules is equal. In other embodiments, there are two separate PCBs 2000 for each row of TE modules (for example, there can be two PCBs stacked between adjacent rows of modules).
FIG. 22 illustrates an array 2200 of TE modules 2208 with wired rows stacked on top of one another. The array 2200 includes PCBs 2202 disposed between stacked rows of modules 2208 and can also include a PCB disposed alongside the top row and/or bottom row of modules. Side members 2204 can be operatively connected to keep the rows within the array registered. The side members 2204 can include slots with which row tabs 2206 engage. In the illustrated embodiment, the row tabs 2206 extend from the PCBs 2202 positioned within the array 2200. At least some of the PCBs 2202 can include conductive traces to facilitate wiring (not shown) within the array. In some embodiments, the side members 2204 are constructed from rigid plastic, printed circuit board material, or another suitable material. In certain embodiments, an outer edge of the row tabs 2206 is flush with an outer surface of the side member 2204.
FIG. 24 shows a perspective view of portions of a TE device assembly 2400 that includes an array 2404 of TE modules positioned in a channel enclosure 2402 (for example, an air guide). The channel enclosure 2402 is configured to route fluid through the array 2404 and keep main fluid flows separate from waste fluid flows.
Although the invention has been described in terms of particular embodiments, many variations will be apparent to those skilled in the art. All such variations are intended to be included within the scope of the disclosed invention and the appended claims.

## Claims

1. An assembly for a thermoelectric heat pump used to cool an enclosed space, the assembly comprising:
an enclosure comprising a main side inlet, a main side outlet, a waste side inlet, and a waste side outlet;
a first thermoelectric module comprising a main side heat exchanger and a waste side heat exchanger; and
a stream divider assembly disposed within the enclosure, the stream divider assembly comprising a waste side channel and a main side channel configured to direct a waste fluid stream in counter flow to and separate from a main fluid stream, the waste side channel configured to direct the waste fluid stream from the waste side inlet through the waste side heat exchanger to the waste side outlet, and the main side channel configured to direct the main fluid stream from the main side inlet through the main side heat exchanger to the main side outlet, wherein the waste fluid stream remains in counter flow to the main fluid stream from the waste side inlet through the waste side heat exchanger to the waste side outlet, and wherein the main fluid stream remains in counter flow to the waste fluid stream from the main side inlet through the main side heat exchanger to the main side outlet, and
wherein, when the assembly is installed for the thermoelectric heat pump to cool the enclosed space, the main side inlet and the main side outlet are positioned inside the enclosed space, and the waste side inlet and the waste side outlet are positioned outside the enclosed space.

2. The assembly of claim 1, wherein the main side inlet and the main side outlet are positioned on a main side of the assembly, and the waste side inlet and the waste side outlet are positioned on a waste side of the assembly, and wherein a plane that is between the main and waste sides of the assembly extends through the assembly parallel to a direction of the counter flow of the waste and main fluid streams.

3. The assembly of claim 1, wherein:
the main side inlet and the main side outlet are positioned on a main side of the assembly, and the waste side inlet and the waste side outlet are positioned on a waste side of the assembly, and
when the assembly is installed for the thermoelectric heat pump to cool the enclosed space, the assembly is positioned in a wall of the enclosed space such that the wall extends along a plane that is between the main and waste sides of the assembly, the wall separating exhaust of the waste side channel from intake of the main side channel to substantially prevent the waste fluid stream from entering the main side channel.

4. The assembly of claim 1, further comprising a second thermoelectric module comprising a main side heat exchanger, wherein the first and second thermoelectric modules are oriented such that the main side heat exchanger of the first thermoelectric module and the main side heat exchanger of the second thermoelectric module face towards one another.

5. The assembly of claim 4, wherein the second thermoelectric module comprises a waste side heat exchanger, and the waste side channel comprises a plurality of waste side channels, and wherein the stream divider assembly is configured to divide the waste fluid stream received through the waste side inlet into the plurality of waste side channels through the waste side heat exchangers of the first and second thermoelectric modules to the waste side outlet, wherein the stream divider assembly is configured to divide the waste fluid stream into the plurality of waste side channels upstream of the waste side heat exchangers with respect to a flow direction of the waste fluid stream.

6. The assembly of claim 5, further comprising a third thermoelectric module comprising a waste side heat exchanger, wherein the second and third thermoelectric modules are oriented such that the waste side heat exchanger of the second thermoelectric module and the waste side heat exchanger of the third thermoelectric module face towards one another.

7. The assembly of claim 6, wherein the third thermoelectric module comprises a main side heat exchanger, and the main side channel comprises a plurality of main side channels, and wherein the stream divider assembly is configured to divide the main fluid stream received through the main side inlet into the plurality of main side channels through the main side heat exchangers of the first, second, and third thermoelectric modules to the main side outlet.

8. The assembly of claim 1, further comprising:
a first fan operatively connected to provide flow of the waste fluid stream in the waste side channel; and
a second fan operatively connected to provide flow of the main fluid stream in the main side channel in an opposite direction of the flow of the waste fluid stream in the waste side channel.

9. The assembly of claim 1, wherein the main side inlet on a first end of the assembly is substantially symmetric to the main side outlet on a second end of the assembly opposite the first end, and the waste side outlet on the first end of the assembly is substantially symmetric to the waste side inlet on the second end of the assembly.

10. A thermoelectric heat pump comprising:
an enclosure comprising a main inlet, a main outlet, a waste inlet, and a waste outlet;
a plurality of thermoelectric modules each comprising a main junction and a waste junction; and
a stream divider assembly connected to the enclosure, the stream divider assembly comprising a waste channel and a plurality of main channels configured to direct a waste fluid stream in counter flow to a main fluid stream, the waste channel configured to direct the waste fluid stream from the waste inlet through waste junctions of the plurality of thermoelectric modules to the waste outlet, and the plurality of main channels configured to divide the main fluid stream from the main inlet through main junctions of the plurality of thermoelectric modules and to combine the main fluid stream from the main junctions to the main outlet, wherein the waste fluid stream remains in counter flow to the main fluid stream from the waste inlet through the waste junctions of the plurality of thermoelectric modules toward the waste outlet.

11. The thermoelectric heat pump of claim 10, wherein the plurality of thermoelectric modules are oriented such that at least two of the waste junctions face towards one another.

12. The thermoelectric heat pump of claim 10, wherein the waste channel comprises a plurality of waste channels, and wherein the plurality of waste channels are configured to divide the waste fluid stream from the waste inlet through the waste junctions of the plurality of thermoelectric modules and to combine the waste fluid stream from the waste junctions to the waste outlet, wherein the stream divider assembly divides the waste fluid stream into the plurality of waste channels upstream of the waste junctions with respect to flow direction of the waste fluid stream.

13. The thermoelectric heat pump of claim 12, wherein the plurality of thermoelectric modules are oriented such that at least two of the main junctions face towards one another between at least two of the plurality of waste channels.

14. The thermoelectric heat pump of claim 12, wherein the plurality of waste channels are symmetric about the plurality of thermoelectric modules along a direction of the counter flow of the waste and main fluid streams, and wherein the plurality of main channels are symmetric about the plurality of thermoelectric modules along the direction of the counter flow of the waste and main fluid streams.

15. The thermoelectric heat pump of claim 10, wherein, when the thermoelectric heat pump is installed for use with an enclosed space, the main inlet and the main outlet are positioned inside the enclosed space, and the waste inlet and the waste outlet are positioned outside the enclosed space to substantially prevent the waste fluid stream from entering the plurality of main channels.

16. The thermoelectric heat pump of claim 10, further comprising:
a first fan capable of providing flow of the waste fluid stream in the waste channel; and
a second fan capable of providing flow of the main fluid stream in the plurality of main channels in an opposite direction of the flow of the waste fluid stream in the waste channel.

17. The assembly of claim 1, wherein the stream divider assembly is configured to direct the main fluid stream in substantially a first direction from the main side inlet toward the first thermoelectric module and direct the main fluid stream in substantially the first direction toward of the main side outlet away from the first thermoelectric module.

18. The assembly of claim 17, wherein the stream divider assembly is configured to direct the waste fluid stream in substantially a second direction from the waste side inlet toward the first thermoelectric module and direct the waste fluid stream in substantially the second direction toward of the waste side outlet away from the first thermoelectric module, wherein first direction is counter to the second direction.

19. The assembly of claim 1, wherein the stream divider assembly comprises an S-shaped channel configured to direct the waste fluid stream about the main fluid stream.

20. The assembly of claim 1, wherein the stream divider assembly comprises an S-shaped channel configured to direct the main fluid stream about the waste fluid stream.

21. The assembly of claim 1, wherein the stream divider assembly comprises wedge shaped projections configured to contact the first thermoelectric module at boundaries between the main side heat exchanger and the waste side heat exchanger such that leakage between the waste side channel and the main side channel at a junction between the stream divider assembly and the first thermoelectric module is inhibited.

22. The assembly of claim 5, wherein the waste side heat exchanger comprises heat exchange fins separate from the stream divider assembly that is configured to divide the waste fluid stream received through the waste side inlet into the plurality of waste side channels.

23. The thermoelectric heat pump of claim 10, wherein the main inlet is a single inlet of the enclosure, and wherein the stream divider assembly is configured to divide the main fluid stream into the plurality of main channels upstream of the main junctions with respect to a flow direction of the main fluid stream.

24. The thermoelectric heat pump of claim 10, wherein the main fluid stream remains in counter flow to the waste fluid stream from the main inlet through the main junctions of the plurality of thermoelectric modules toward the main outlet.

25. The thermoelectric heat pump of claim 10, wherein the stream divider assembly comprises an S-shaped channel configured to direct the waste fluid stream about the main fluid stream.

26. The thermoelectric heat pump of claim 25, wherein the S-shaped channel is configured to direct the waste fluid stream to a full geometric extent a heat transfer region associated with the waste junction.

27. The thermoelectric heat pump of claim 10, wherein the stream divider assembly comprises an S-shaped channel configured to direct the main fluid stream about the waste fluid stream.

28. The thermoelectric heat pump of claim 27, wherein the S-shaped channel is configured to direct the main fluid stream to a full geometric extent a heat transfer region associated with the main junction.

29. The thermoelectric heat pump of claim 10, wherein the main side inlet and the main side outlet are on a same side of the enclosure.