Busbars for immersion-cooling systems

Abstract

Busbars, power bars, and feed-thru assemblies are described to carry power through the wall of a tank used in an immersion-cooling system and to distribute power to components within the tank. A busbar and power bar can comprise multiple conductive layers laminated together and separated by insulating material. The feed-thru assemblies can form an airtight and / or liquid-tight seal with the tank where electrical conductors pass through the tank wall. The feed-thru assemblies can allow movement of the tank wall with respect to the head of the busbar while maintaining a seal during system operation.

Description

Busbars for Immersion-Cooling SystemsCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application claims a priority benefit, under 35 U.S.C. § 1 19(e), to U.S. provisional application Ser. No. 63 / 514,259 filed on July 18, 2023, titled “Busbar for Immersion- Cooling System,” which application is incorporated herein by reference in its entirety. The present application also claims a priority benefit, under 35 U.S.C. § 119(e), to U.S. provisional application Ser. No. 63 / 515,423 filed on July 25, 2023, titled “Busbar for Immersion-Cooling System,” which application is incorporated herein by reference in its entirety.BACKGROUND

[0002] As feature sizes and transistor sizes have decreased for integrated circuits (ICs), the amount of heat generated by a single chip, such as a microprocessor, has increased. Chips that once were air cooled have evolved to chips needing more heat dissipation than can be provided by air alone. In some cases, immersion cooling of chips in a tank containing a coolant liquid is employed to maintain IC chips at appropriate operating temperatures.

[0003] One type of immersion cooling is two-phase immersion cooling, in which heat generated from a semiconductor die is high enough to boil the coolant liquid that contacts the semiconductor die or a heat-dissipating element that is thermally coupled to the semiconductor die. The boiling creates a coolant-liquid vapor in the tank, which is condensed by cooling coils back to liquid form. Heat from the semiconductor dies can then be sunk into the liquid-to-gas and gas-to-liquid phase transitions of the coolant liquid.SUMMARY

[0004] The present disclosure relates to busbars, power bars, busbar feed-thru assemblies, and related methods for delivering power to components in a tank of an immersion-cooling system. The described apparatus can be used for high power delivery (e.g, power levels exceeding 100,000 Watts).

[0005] Some implementations relate to multilayer busbars for immersion-cooling systems. Example multilayer busbars can comprise: a multilayer base bar having two or more conductive layers separated by insulating material between each pair of adjacent conductive layers of the two or more conductive layers; a multilayer riser electrically connected to the multilayer base bar and having a same number of conductive layers as the multilayer base bar; and a multilayer head electrically connected to the multilayer riser and having the same number of conductive layers as the multilayer base bar, wherein the multilayer head is configured to pass through an opening in a wall of a tank of the immersion-cooling system.

[0006] Some implementations relate to methods of delivering power from an external power source to components inside a tank of an immersion-cooling system. Such methods can comprise acts of: receiving power on a multilayer busbar from a multilayer power bar, wherein the multilayer busbar comprises: a multilayer base bar having two or more conductive layersseparated by insulating material between each pair of adjacent conductive layers of the two or more conductive layers; a multilayer riser electrically connected to the multilayer base bar and having a same number of conductive layers as the multilayer base bar; and a multilayer head electrically connected to the multilayer riser and having the same number of conductive layers as the multilayer base bar, wherein the multilayer head passes through an opening in a wall of the tank and connects to the multilayer power bar.

[0007] Some implementations relate to feed-thru assemblies to maintain a seal around a portion of a busbar that passes through a wall of a tank in an immersion-cooling system. Such feed-thru assemblies can comprise: a soft, compliant shell; a first flange at a first sealing end of the shell to form a first seal with the wall of the tank; and a second flange at a second sealing end of the shell to form a second seal with an external flange, wherein the shell is deformable to allow motion of the wall with respect to the portion of the busbar while maintaining an airtight seal around the portion of the busbar.

[0008] All combinations of the foregoing concepts and additional concepts discussed in greater detail below (provided such concepts are not mutually inconsistent) are part of the inventive subject matter disclosed herein. In particular, all combinations of subject matter appearing in this disclosure are part of the inventive subject matter disclosed herein. The terminology used herein that also may appear in any disclosure incorporated by reference should be accorded a meaning most consistent with the particular concepts disclosed herein.BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The skilled artisan will understand that the drawings primarily are for illustrative purposes and are not intended to limit the scope of the inventive subject matter described herein. The drawings are not necessarily to scale; in some instances, various aspects of the inventive subject matter disclosed herein may be shown exaggerated or enlarged in the drawings to facilitate an understanding of different features. In the drawings, like reference characters generally refer to like features (e.g., functionally similar and / or structurally similar components).

[0010] FIG. 1 depicts a first example of a busbar that can be used to deliver power inside a tank of an immersion-cooling system.

[0011] FIG. 2A depicts a second example of a multilayer busbar and related structure that can be used to deliver power inside a tank of an immersion-cooling system. A feed-thru assembly is depicted at the head of the busbar.

[0012] FIG. 2B depicts the multilayer busbar of FIG. 2A with a different feed-thru assembly.

[0013] FIG. 3 depicts socket hole patterns in the multilayer base bar of the busbar of FIG. 2A.

[0014] FIG. 4 depicts further details of the feed-thru assembly of FIG. 2A.

[0015] FIG. 5A and FIG. 5B depict one approach for sealing an external casing and mating flange to the multilayer power bar of FIG. 4.

[0016] FIG. 6 depicts a feed-thru assembly that can be implemented with the busbars described herein.DETAILED DESCRIPTION

[0017] 1. Single-layer Busbar

[0018] FIG. 1 depicts an example of a busbar 100 that can be used to deliver electrical power from a power source outside a tank of an immersion-cooling system to components (e.g, printed circuit boards containing processors and / or memory such as high bandwidth memory) inside the tank. The amount of power delivered can be very high (e.g., from approximately or exactly 100,000 Watts to approximately or exactly 600,000 Watts or more). The busbar 100 of FIG. 1 can mount or be attached to the bottom of a tank of an immersion-cooling system in some implementation, or the busbar 100 can mount to any wall or interior surface of an immersioncooling system’s tank. The tank includes coolant liquid and at least a portion of the busbar 100 is immersed in the coolant liquid.

[0019] The busbar 100 can comprise a conductive base bar 108, a conductive riser 1 18, and a conductive head 128 that are electrically coupled together. The conductive base bar 108 can comprise a conductive first base bar 102 and a conductive second base bar 104 for distributing power to electronic components in a tank of the immersion-cooling system. The conductive riser can comprise a conductive first rising bar 112 and a conductive second rising bar 114 providing electrical coupling between the base bar 108 and the head 128. The conductive head can comprise a conductive first terminal 122 and a conductive second terminal 124 for electrical coupling to at least one external power source. The first base bar 102 and the second base bar 104 can each have a plurality of holes 105 (which may or may not be threaded) for one or more components inside the tank to make electrical contact to the first base bar 102 so that power can be provided from the first base bar 102 and the second base bar to the one or more components inside the tank of the immersion-cooling system. The first base bar 102 and second base bar 104 are electrically isolated from each other to provide, for example, a positive voltage (or a negative voltage) on one bar and reference potential (or opposite polarity voltage) on the other bar. In some cases, posts or pins can be used instead of, or in combination with, the holes 105 to make electrical contact with the one or more components inside the tank. In some implementations, sockets can be installed in the plurality of holes for making electrical connections, as described further below. The first base bar 102 and second base bar 104 can run side-by-side and fit in a tray that may or may not be submerged in coolant liquid in the tank.

[0020] The plurality of holes 105 can extend along at least a portion of the first base bar 102 and second base bar 104. The plurality of holes 105 can be arranged in any suitable pattern, (e.g, a regular pattern comprising two rows of holes shown in FIG. 1). The center-to-center spacing of adjacent holes in the plurality of holes 105 along the direction of the row (y direction) can be from approximately or exactly 20 mm to approximately or exactly 100 mm.|00211 The busbar 100 can further comprise a conductive first rising bar 112 and a conductive second rising bar 114 that are electrically isolated from each other. The first rising bar 112 canelectrically couple to the first base bar 102. The second rising bar 114 can electrically couple to the second base bar 104. The rising bars can extend along and run adjacent to a wall of the tank (e.g., rise from the bottom of the tank and run up along a side wall of the tank.

[0022] In some implementations, the first rising bar 112 can mechanically couple to the first base bar 102. Similarly, the second rising bar 114 can mechanically couple to the second base bar 104. In some cases, the first rising bar 112 and the second rising bar 114 can each be integrally formed with their respective base bars. For example, the first rising bar 112 can comprise an extension of the same material used to form the first base bar 102, wherein the first rising bar 112 comprises a portion of the material that is bent to an angle Oi from the first base bar 102.

[0023] The first terminal 122 can be electrically coupled to the first base bar 102 via the first rising bar 112. The first terminal 122 can be mechanically attached (e.g., screwed, bolted, riveted, brazed, or soldered) to the first rising bar 112. The second terminal 124 can be electrically coupled to the second base bar 104 via the second rising bar 114, and also can be mechanically attached to the second rising bar 114. The first terminal 122 is electrically isolated from the second terminal 124.|0024| The first terminal 122 and second terminal 124 can be configured to extend through a wall 150 of the immersion-cooling tank so as to electrically couple to a power source outside the tank. For example, a connector (or connectors) from a power source can connect to portions of the first terminal 122 and second terminal 124 that are located outside the immersion-cooling tank.

[0025] The first terminal 122 and second terminal 124 may or may not be located below the surface of coolant liquid in the tank when the immersion cooling system is in operation. When at least portions of the first terminal 122 and second terminal 124 are submerged inside the tank a liquid-proof seal can be used where the first terminal 122 and second terminal 124 extend through the wall 150 of the tank so that coolant liquid does not leak outside the tank. When the first terminal 122 and second terminal 124 are not submerged inside the tank and located in a gas space above the coolant liquid, an airtight seal can be used where the first terminal 122 and second terminal 124 extend through the wall 150 of the tank so that gas within the tank does not leak outside the tank.

[0026] The base bars 102, 104, rising bars 112, 114, and terminals 122, 124 can each comprise and be formed from one or more suitable conductive metals such as, but not limited to copper, copper alloys, aluminum, aluminum alloys, silver, silver alloys, rhodium, rhodium alloys, zinc, zinc alloys, nickel, nickel alloys, or some combination thereof. The same conductive metal can be used for all of the base bars, rising bars, and terminals, though these components can comprise different conductive metals.

[0027] Example lengths Lb of the first base bar 102 and second base bar 104 can be from approximately or exactly 500 mm to approximately or exactly 2000 mm though shorter and longer lengths can be used in some implementations. In some cases, the length of the first basebar 102 and of the second base bar 104 can be from approximately or exactly 1300 mm to approximately or exactly 1700 mm. In some implementations, the length of the first base bar 102 can be different than the length of the second base bar 104.

[0028] Example widths Wb of the busbar 100 (when the first base bar 102 and second base bar 104 are mounted side-by-side as illustrated in FIG. 1) can be from approximately or exactly 100 mm to approximately or exactly 500 mm though narrower and wider widths can be used in some implementations. In some cases, the busbar width can be from approximately or exactly 200 mm to approximately or exactly 400 mm. In some implementations, the width of the first base bar 102 can be different than the width of the second base bar 104.

[0029] Example thicknesses th of the first base bar 102 and second base bar 104 can be from approximately or exactly 2 mm to approximately or exactly 10 mm, though thinner and thicker base bars can be used in some implementations. In some cases, the thickness of the base bars can be from approximately or exactly 3 mm to approximately or exactly 7 mm. In some implementations, the thickness of the first base bar 102 can be different than the thickness of the second base bar 104.

[0030] Example heights H of the busbar 100 (measured from the bottom of the first base bar 102 and second base bar 104 to the tops of the first terminal 122 and second terminal 124) can be from approximately or exactly 200 mm to approximately or exactly 1500 mm, though shorter or taller heights can be used in some implementations. In some cases, the height of the busbar 100 can be from approximately or exactly 300 mm to approximately or exactly 600 mm.|00311 The widths and thicknesses of the first rising bar 112 and second rising bar 114 can be the same as or different from the widths and thickness of the first base bar 102 and second base bar 104. The lengths of the first rising bar 112 and second rising bar 114 can be commensurate with the above-described heights H of the busbar 100. In some implementations, the length of the first rising bar 112 can be different from the length of the second rising bar 114 such that the first terminal 122 is located at a different elevation (or different z position) than the second terminal 124.

[0032] Example lengths Lt of the first terminal 122 and second terminal 124 can be from approximately or exactly 100 mm to approximately or exactly 500 mm though shorter and longer lengths can be used in some implementations. In some cases, the lengths of the first terminal 122 and second terminal 124 can be from approximately or exactly 200 mm to approximately or exactly 400 mm. In some implementations, the first terminal 122 can have a different length than the second terminal 124.

[0033] Example widths Wtof the first terminal 122 and second terminal 124 can be from approximately or exactly 100 mm to approximately or exactly 500 mm though narrower and wider widths can be used in some implementations. In some cases, the widths of the first terminal 122 and second terminal 124 can be from approximately or exactly 200 mm to approximately or exactly 400 mm. In some implementations, the first terminal 122 can have a different width than the second terminal 124.

[0034] Example thicknesses tt of the first terminal 122 and second terminal 124 can be from approximately or exactly 2 mm to approximately or exactly 8 mm, though thinner and thicker terminals can be used in some implementations. In some cases, the thickness of the first terminal 122 and second terminal 124 can be from approximately or exactly 3 mm to approximately or exactly 7 mm. In some implementations, the first terminal 122 can have a different thickness than the second terminal 124.

[0035] A first angle 0i between the base bars 102, 104 and rising bars 112, 114 can be from approximately or exactly 75 degrees to approximately or exactly 105 degrees, though more acute angles and more obtuse angles can be used in some implementations. In some cases, the first angle 9i is from approximately or exactly 85 degrees to approximately or exactly 95 degrees.

[0036] A second angle O2 between the rising bars 112, 114 and the terminals (first terminal 122, second terminal 124) can be from approximately or exactly 75 degrees to approximately or exactly 105 degrees, though more acute angles and more obtuse angles can be used in some implementations. In some cases, the second angle 02 is from approximately or exactly 85 degrees to approximately or exactly 95 degrees. The first terminal 122 and second terminal 124 may or may not extend in a direction that is parallel to the direction in which the base bars 102, 104 extend.

[0037] The first base bar 102 and first rising bar 112 can be separated by at least one distance from the second base bar 104 and the second rising bar 114 (in the x direction in FIG. 1). The separation distance for the conductive elements of the base bar 108 and the conductive elements of the riser 118 can be from approximately or exactly 1 mm to approximately or exactly 5 mm, though smaller and larger separations are possible in some implementations.

[0038] 2. Multilayer Busbar

[0039] FIG. 2A and FIG. 2B depicts other examples of busbars 200 that can be used to deliver electrical power from a power source outside a tank of an immersion-cooling system to electronic components 280 (e.g, printed circuit boards containing processors and / or memory such as high bandwidth memory) inside the tank. The amount of power carried by the busbars 200 can be from approximately or exactly 100,000 Watts to approximately or exactly 600,000 Watts or even higher. The busbars 200 of FIG. 2A and FIG. 2B can mount to the bottom of a tank (or on any wall or interior surface) of an immersion-cooling system. The busbars of FIG. 2A and FIG. 2B each comprise a multilayer conductor assembly and therefore may be referred to as “multilayer busbars.” Each busbar 200 comprises a multilayer base bar 208 extending a first length (in approximately the y direction of the illustration), a multilayer riser 218 extending a second length (in approximately the z direction), and a multilayer head 228 extending a third length (in approximately the y direction). The multilayer head is electrically coupled to the multilayer base bar 208 via the multilayer riser 218.

[0040] The multilayer conductor assembly of each busbar 200 comprises two or more conductive layers 301 , 302, 303, 304 laminated together with electrically-insulating material 307 (e.g, a thin film of polymer) located between adjacent conductive layers of the two or moreconductive layers. The conductive layers are more visible in FIG. 3. In some implementations, the conductive layers 301, 302, 303, 304 can be continuous strips or sheets of conductive metal extending from the multilayer head 228 to the end of the multilayer base bar 208 that are bent to form the multilayer riser 218 and multilayer head 228. In some implementations, the conductive layers 301, 302, 303, 304 can be pieced together (e.g., connected section by section such that the sections are electrically coupled to the multilayer base bar 208. For example, the multilayer riser 218 and multilayer head 228 may be formed as separate pieces that are connected together and also connected to the multilayer base bar 208.

[0041] The thickness of each conductive layer 301, 302, 303, 304 on the multilayer base bar 208, multilayer riser 218, and multilayer head 228 can be from approximately or exactly 0.5 mm to approximately or exactly 8 mm. In some cases, the thickness of each conductive layer 301, 302, 303, 304 can be from approximately or exactly 1 mm to approximately or exactly 2 mm. The thicknesses of the conductive layers 301, 302, 303, 304 throughout the busbar may or may not be the same as each other.

[0042] Alternating layers of the multilayer conductor assembly can connect to a common source potential (e.g., conductive layers 301 and 303 can connect to a positive voltage source while conductive layers 302 and 304 connect to a reference potential such as ground or a negative voltage source). Because of the multilayer design, the busbars 200 of FIG. 2A and FIG. 2B can have a significant reduction in inductance compared to the busbar 100 of FIG. 1. Although four conductive layers are depicted in the illustrations, a multilayer busbar can have more than four conductive layers or fewer than four conductive layers.|0043| In some implementations, alternating layers of the multilayer conductor assembly can connect to different source potentials to deliver different voltages to components 280 in the immersion-cooling tank. For example, conductive layer 301 and conductive layer 303 can connect to two different positive voltage sources while conductive layers 302, 304 connect to reference potentials (such as ground) for the two voltage sources.

[0044] The multilayer riser 218 can be long enough to extend above the coolant liquid when the immersion-cooling system is operating such that the multilayer head 228 can pass through the wall of the tank for connecting to one or more power sources outside the tank without being immersed in coolant liquid. A feed-thru assembly 230, 231 can be located above the coolant liquid level. The feed-thru assembly 230, 231 can be airtight to prevent gas and vapor from leaking out of the tank at the feed-thru assembly.

[0045] In some implementations, the multilayer riser 218 may not extend above the coolant liquid such that the multilayer head 228 passes through the wall of the tank and connects to one or more power sources outside the tank using a feed-thru assembly 230, 231 located below the coolant liquid level. The feed-thru assembly 230, 231 can be liquid-tight such that no coolant liquid leaks from the feed-thru assembly to an external environment outside the tank and the feed-thru assembly.

[0046] The conductive layers 301, 302, 303, 304 of the multilayer conductor assembly can be formed from one or more suitable conductive metals such as, but not limited to copper, copper alloys, aluminum, aluminum alloys, silver, silver alloys, rhodium, rhodium alloys, zinc, zinc alloys, nickel, nickel alloys, or some combination thereof. The conductive layers can be bent into roughly an S configuration, as depicted in FIG. 2A and FIG. 2B, before or after lamination with insulating material and other conductive layers in the assembly. The conductive layers 301, 302, 303, 304 and intervening insulating material can be bonded together (e.g, with an adhesive) or otherwise bound together (e.g, with clamps or mounting fixtures) to thus form an assembly having multiple laminated layers of material.

[0047] According to some implementations, the multilayer base bar 208 can fit within a tray 340 within the tank. The tray 340 can alternatively receive the first base bar 102 and second base bar 104 of the busbar 100 illustrated in FIG. 1, so that either type of busbar could be used in the tank. However, a different tray could be used for each type of busbar described herein.

[0048] The multilayer base bar 208 can include a plurality of holes 305 formed therein for making electrical connections between one or more conductive layers of the multilayer base bar 208 and electronic components 280 in the tank. The plurality of holes 305 can be arranged in a pattern that matches a pattern of holes 350 in the tray 340 to allow insertion of connectors in electrical sockets 360. The pattern can be, for example, a double row of holes with each row extending along a length Lb of the multilayer base bar 208. As illustrated in FIG. 3, each electrical socket 360 can electrically couple to one conductive layer of the multilayer base bar 208. The electrical sockets 360 can each be secured in their holes by an interference fit, soldering, and / or sintering. Alternatively, pins or posts for making electrical contact could be secured in the holes in the same way.

[0049] To avoid electrical contact with adjacent conductive layers, the plurality of holes 305 can comprise a first portion of holes having a first diameter and a second portion of holes having a second diameter smaller than the first diameter. The holes having the first diameter can be formed in the adjacent conductive layers of the multilayer base bar 208 that align to a hole having the second smaller diameter, into which an electrical socket 360, pin, post, or screw can be inserted. The larger diameter of the first holes formed in the adjacent layer(s) can be large enough, for example, to allow passage of a pin or other contact element (which may be coupled to a conductive wire or cable, for example) through the adjacent layers (without electrical coupling to the adjacent layers) to electrically contact the electrical socket 360 and couple to one selected layer of the conductive layers, as should be clear from the illustration of FIG. 3.

[0050] An example electrical socket 360 that could be installed in the smaller holes formed in the multilayer base bar 208 is the Molex Sentrality power socket. An example contact element that inserts into the electrical socket is the Molex Sentrality power pin. The power pins 282 (FIG. 2A) can mount on an electronic component 280 (such as a printed circuit board (PCB)) such that a pair of pins 282 can insert into a pair of electrical sockets to provide power (voltage and current) to the electronic component 280. Electrical sockets 360 can also be installed in the plurality of holes 105 for the busbar 100 of FIG. 1.

[0051] The plurality of holes 305 can extend along at least a portion of the multilayer base bar 208. The plurality of holes 305 can be arranged in any suitable pattern, (e.g, a regular pattern comprising two rows of holes shown in FIG. 3). The center-to-center spacing of adjacent smaller holes (for which electrical contact is made) in the plurality of holes 305 along the direction of the row (y direction) can be from approximately or exactly 20 mm to approximately or exactly 100 mm. The diameter of the smaller holes in a conductive layer into which the electrical sockets, pins, or posts insert can be from approximately or exactly 5 mm to approximately or exactly 40 mm.

[0052] Insulating material located between the conductive layers of the multilayer base bar 208, multilayer riser 218, and multilayer head 228 can comprise a polymer, organic compound, ceramics, paper, and / or a glass (e.g., a glass). Example insulating materials include, but are not limited to, polyethylene terephthalate (PET), polyimide, polycarbonate (PC), polyethylene terephthalate (also known as Teflon), polyether ether ketone (PEEK). The insulating material can be adhered to the adjacent conductive layers with an adhesive or may include a tacky substance on opposite surfaces and be applied as a double-sided tape to bond adjacent conductive layers of the multilayer busbar together.

[0053] Example lengths Lb of the multilayer base bar 208 can be from approximately or exactly 500 mm to approximately or exactly 2000 mm though shorter and longer lengths can be used in some implementations. In some cases, the multilayer base bar 208 length can be from approximately or exactly 1300 mm to approximately or exactly 1700 mm.

[0054] Example widths Wb of the multilayer base bar 208 can be from approximately or exactly 100 mm to approximately or exactly 500 mm though narrower and wider widths can be used in some implementations. In some cases, the base bar width can be from approximately or exactly 200 mm to approximately or exactly 400 mm.

[0055] Example thicknesses th of the multilayer base bar 208 can be from approximately or exactly 2 mm to approximately or exactly 10 mm, though thinner and thicker base bars can be used in some implementations. In some cases, the base bar thickness can be from approximately or exactly 3 mm to approximately or exactly 7 mm.

[0056] Example heights H of the multilayer busbar (measured from the bottom of the multilayer base bar 208 to the top of the multilayer head 228) can be from approximately or exactly 200 mm to approximately or exactly 1500 mm, though shorter or taller heights can be used in some implementations. In some cases, the height of the multilayer busbar can be from approximately or exactly 800 mm to approximately or exactly 1200 mm. The length of the multilayer riser 218 (measured in the z direction according to the drawings) can be from approximately or exactly 200 mm to approximately or exactly 1500 mm, though shorter or taller heights can be used in some implementations. In some cases, the length of the multilayer riser 218 is selected to place the multilayer head 228 above the maximum height of the liquid coolant in the tank when the immersion-cooling system is operating.

[0057] The width and thickness of the multilayer riser 218 can be the same as or different from the width and thickness of the multilayer base bar 208 (e.g., within 10%, 5%, or 2% the width of the base bar). The length of the multilayer riser 218 can be commensurate with the abovedescribed heights H of the busbar.

[0058] Example lengths Lt of the multilayer head 228 can be from approximately or exactly 100 mm to approximately or exactly 500 mm though shorter and longer lengths can be used in some implementations. In some cases, the length of the multilayer head 228 can be from approximately or exactly 200 mm to approximately or exactly 400 mm. The length of the multilayer head can be long enough such that the multilayer head extends through an opening in the wall of the tank used in the immersion-cooling system.

[0059] Example widths IE of the multilayer head 228 can be from approximately or exactly 100 mm to approximately or exactly 500 mm though narrower and wider widths can be used in some implementations. In some cases, the width of the multilayer head 228 can be from approximately or exactly 200 mm to approximately or exactly 400 mm.

[0060] Example thicknesses h of the multilayer head 228 can be from approximately or exactly 2 mm to approximately or exactly 10 mm, though a thinner and thicker multilayer head 228 can be used in some implementations. In some cases, the thickness of the multilayer head 228 can be from approximately or exactly 3 mm to approximately or exactly 7 mm.

[0061] A first angle 0i between the multilayer base bar 208 and multilayer riser 218 can have a value from approximately or exactly 75 degrees to approximately or exactly 105 degrees, though more acute angles and more obtuse angles can be used in some implementations. In some cases, the first angle Oi is from approximately or exactly 85 degrees to approximately or exactly 95 degrees.

[0062] A second angle 62 between the multilayer riser 218 and the multilayer head 228 can have a value from approximately or exactly 75 degrees to approximately or exactly 105 degrees, though more acute angles and more obtuse angles can be used in some implementations. In some cases, the second angle O2 is from approximately or exactly 85 degrees to approximately or exactly 95 degrees. The multilayer head 228 may or may not extend in a direction that is parallel to the direction in which the multilayer base bar 208 extends (>’ direction).

[0063] FIG. 4 illustrates further details of the feed-thru assembly 230 of FIG. 2A according to one embodiment. The conductive layers 301, 302, 303, 304 of the multilayer head 228 can terminate such that they are offset from one another outside the tank, as illustrated, or inside the tank. In some cases, the ends of the conductive layers 301 , 302, 303, 304 can terminate inside the feed-thru assembly 230, for example, though in some implementations the ends can terminate outside the feed-thru assembly 230. To receive power, the multilayer head 228 can electrically connect to a multilayer power bar 410 (which connects to one or more power sources). The multilayer head 228 can connect to the multilayer power bar 410 with a clamp, screws, bolts, or other fastening means. For each conductive layer of the multilayer head 228 and multilayer power bar 410, insulating material for mating surfaces of the conductive layers can be removedat the coupling region between the multilayer head 228 and power bar 410 to establish electrical connections between the corresponding conductive layers when the conductive layers are clamped together.

[0064] In some implementations, the multilayer head 228 of the busbar 200 is configured to couple to an external multilayer power bar 410. For example, the multilayer head 228 can comprise a plurality of holes 405 for connecting to the multilayer power bar 410 with screws that extend through the holes to fasten and clamp ends of the multilayer head 228 and ends of the multilayer power bar 410 to each other. In some cases, the ends of the multilayer head 228 and / or the ends of the multilayer power bar 410 can be secured in a connector assembly (like a large USB connector) that provides for a friction-fit connection and electrical coupling. In some cases, pins and electrical sockets (like those used on the multilayer base bar 208) can be used to connect a conductive layer of the multilayer head 228 to a conductive layer of the multilayer power bar 410. The electrical connection between the multilayer head 228 and multilayer power bar 410 can be inside the feed-thru assembly 230 or outside the feed-thru assembly.

[0065] The feed-thru assembly 230, depicted in FIG. 4, can be used to form an air-tight and / or liquid-tight seal around the opening in the tank wall 150 of the immersion-cooling system through which the multilayer head 228 or the multilayer power bar 410 passes. In some cases, the feed-thru assembly 230 can also enclose the connection of the multilayer head 228 of the busbar of FIG. 2A to the multilayer power bar 410 located outside the tank of an immersioncooling system. However, the connection of the multilayer head 228 to the multilayer power bar 410 need not be located within the feed-thru assembly 230. In some cases, the connection of the multilayer head 228 to the multilayer power bar 410 can be located inside the tank or located outside the tank and beyond the feed-thru assembly 230.

[0066] In some implementations, the feed-thru assembly 230 can comprise a first flange plate 422, a second flange plate 424, and a sealing piece 430. The sealing piece 430 comprises a first sealing end 432, a tubular, compliant shell 435, and a second sealing end 434. The first sealing end 432 can be flanged and connected to the shell 435 (e.g, integrally formed with the shell in a molding process), so that the first sealing end 432 can form a first portion of the liquid-tight and / or air-tight seal to the wall 150 of the immersion-cooling tank. The second sealing end 434 can also be flanged and connected to the shell 435 (e.g, also integrally formed with the shell), so that the second sealing end 434 can form a second portion of the seal to a mating flange 440 located on the multilayer power bar 410 (or on the multilayer head 228 if the connection between the two components is located outside the tank and beyond the feed-thru assembly 230. When the sealing piece 430 is mounted to the tank, the first sealing end 432 can be sandwiched between the tank wall 150 and a first flange plate 422 to form an airtight and / or liquid-tight seal with the tank wall 150. The second sealing end 434 can be sandwiched between the mating flange 440 and the second flange plate 424. The mating flange 440 can be sealed to the multilayer power bar 410 (or the multilayer head 228) so that an airtight and / or liquid-tight seal is formed with the multilayer power bar or multilayer head outside the tank.

[0067] The feed-thru assembly 230 can comprise a soft, flexible sealing piece 430 (e.g., formed from a polymer) having flanged ends to form an airtight and / or liquid-tight seal with the tank wall 150 and with the mating flange 440. The sealing piece 430 can be formed from a soft material to act as a flexible gasket. For example, the first sealing end 432, the second sealing end 434, and the compliant shell 435 can be formed from silicone or nitrile rubber or any flexible material that is compatible with coolant liquid used in the immersion-cooling system.

[0068] The first sealing end 432 and second sealing end 434 of the sealing piece 430 can have predetermined patterns of holes for screws to pass through when the sealing ends are flanged. The patterns of holes at the first sealing end can match a corresponding hole pattern and / or screw pattern on the tank wall 150 and on the first flange plate 422. The pattern of holes at the second sealing end 434 can match hole patterns in the second flange plate 424 and / or on the mating flange 440 that is sealed to the multilayer power bar 410. Screws or bolts can be used to fasten the first flange plate 422 securely to the tank wall 150 at the first sealing end 432 of the sealing piece 430. Screws or bolts can fasten the second flange plate 424 securely to the mating flange 440 at the second sealing end 434 of the sealing piece 430.

[0069] More generally, the first sealing end 432 and second sealing end 434 of the sealing piece 430 can be formed in any shape (e.g, flanged, no flange, tubular) or comprise different shapes at the two ends. The first sealing end 432 can be configured to form a first portion of the seal with the tank wall (and / or a fixture mounted on the tank wall). The second sealing end 434 can be configured to form a second portion of the seal with a mating piece. The mating piece may be flanged, have no flange, or tubular. In some implementations, the mating piece can be the multilayer head 228 itself or the multilayer power bar 410 itself and the second sealing end 434 can be tubular and sized to seal to the multilayer head 228 or the multilayer power bar 410. For example, the second sealing end can slide over and clamp to the multilayer head 228 or the multilayer power bar 410.

[0070] At the wall 150 of the tank near the feed-thru assembly 230, the multilayer head 228 of the busbar 200 may not touch or be secured to the tank wall 150. As such, the tank wall 150 can move with respect to the multilayer head 228 and the multilayer power bar 410, as pressure inside the tank changes. Because the tank can be large and operate under significantly different pressures over time, the tank wall 150 can deflect outward (+y direction) and inward (-y direction) as pressure in the tank increases and decreases, respectively. Movement of the tank wall 150 can be accommodated by the compliant shell 435 of the feed-thru assembly 230. For example, the shell 435 can be compressed and stretched in they direction to accommodate movement of the tank wall 150. In some cases, the wall of the shell 435 can be folded or pleated like the bellows of an accordion to accommodate wall movement. To connect the multilayer head 228 to the multilayer power bar 410 when the connection is located inside the shell 435, one end of the shell can be pushed back (before fastening to the tank wall 150 or to the mating flange 440) and the conductive layers electrically connected.

[0071] The feed-thru assembly 23 1 of FIG. 2B can also accommodate movement of the tank wall 150 in an immersion-cooling system. The feed-thru assembly 231 can be located over themultilayer head 228 or the multilayer power bar 410. The feed-thru assembly 231 comprises a casing 450 with a mating flange 440, a gasket 260, and one or more O-rings 270. The O-rings 270 can be formed from compliant material such as silicone, nitrile rubber, or butyl rubber. The mating flange 440 can be integrally formed with the casing 450 or connected to the casing. The mating flange 440 can fasten to the tank wall 150 (not shown in FIG. 2B) and form an airtight and / or liquid tight seal with the tank wall (e.g., by placing the gasket 260 between the mating flange 440 and the tank wall 150 and fastening the mating flange 440 against the gasket 260 to the tank wall 150). One or more O-rings 270 (which may have a rectangular shape) can be disposed between an interior surface of the casing 450 and the outer surface of the multilayer head 228 or multilayer power bar 410. The O-ring(s) 270 can slide along the multilayer power bar 410 or along the multilayer head 228 to permit deflection and movement of the tank wall 150 and feed-thru assembly 23 I relative to the multilayer head 228 and multilayer power bar 410 while maintaining an airtight and / or liquid-tight seal.

[0072] FIG. 5A and FIG. 5B depicts one way in which the mating flange 440 and casing 450 can be sealed to the multilayer power bar 410. Epoxy 510 or other adhesive can be infused into channels 520 formed in conductive layers of the multilayer power bar 410 and also applied around the multilayer power bar 410. The casing 450 and mating flange 440 can be positioned over the epoxy before the epoxy is hardened. The epoxy 510, when hardened can bond and seal the casing 450 and mating flange 440 to the multilayer power bar 410. In some implementations, the casing 450 and mating flange 440 can be placed over the multilayer power bar 410 and the epoxy or other adhesive can be injected into the casing 450 to bond and seal the casing 450 and mating flange 440 to the multilayer power bar 410.

[0073] FIG. 6 depicts another example of a feed-thru assembly in which the sealing piece 630 has no flanged ends. The feed-thru assembly can be used with the busbars of FIG. 1, FIG. 2A, and FIG. 2B. The first sealing end 632 and the second sealing end 634 are tubular. The tubular ends can have any cross-sectional shape (e.g., round, oval, rectangular, etc.). The compliant shell 635 can be pleated or folded as illustrated. At least the compliant shell can be formed from a flexible material described above for the sealing piece 430 of FIG. 4.

[0074] For the example of FIG. 6, the first sealing end 632 can seal to a tubular orifice 620 at the wall 150 of the tank used in the immersion-cooling system. The second sealing end 634 can seal to the multilayer head 228. Alternatively, the second sealing end 634 could seal to a mating piece (flange, tube, etc.) that seals to the multilayer head 228 or the multilayer power bar 410. In some cases, the second sealing end 634 could seal to a connector 650 that is used to couple the multilayer power bar 410 to the multilayer head 228. The connector 650 could be sealed to the power bar 410, for example. The wall 150 can move outward, toward the connector 650, and inward while the compliant shell 635 can flex to compress and extend thereby accommodating motion of the wall 150.

[0075] The illustration of FIG. 6 shows further details of one example of electrical coupling between the multilayer power bar 410 and the multilayer head 228. In this example, insulating material 307 is removed from portions of the conductive layers 301, 302, 303, 304 to allowintimate contact and electrical coupling between conductive layers on the multilayer head 228 and the multilayer power bar 410.

[0076] 3. Methods of Operation

[0077] Methods of operating the busbars described above with immersion-cooling systems are also contemplated. Example methods of operation can include acts of: receiving power on a multilayer busbar from a multilayer power bar, wherein the multilayer power bar is coupled to the at least one power source; and distributing, from the multilayer base bar of the busbar, the power received from the at least one power source to the electronic components inside the tank of the immersion-cooling system. The multilayer busbar can comprise: a multilayer base bar extending a first length; a multilayer riser extending a second length and being electrically coupled to the multilayer base bar; and a multilayer head extending a third length and being electrically coupled to the multilayer riser and electrically coupled to the multilayer power bar. Each of the multilayer base bar, the multilayer riser, and the multilayer head can comprise two or more conductive layers laminated together with insulating material located between adjacent conductive layers of the two or more conductive layers. Additionally, the multilayer base bar can have a plurality of holes formed therein for making electrical connections between the electronic components inside the tank of the immersion-cooling system and the two or more conductive layers of the multilayer base bar.

[0078] Example methods can further comprise maintaining a seal around the multilayer head where the multilayer head passes through an opening in a wall of the tank while the wall of the tank moves during operation of the immersion-cooling system.

[0079] 4. Implementations

[0080] The busbars described above can be implemented and operated in various ways, some of which configurations and methods of operation are listed below.(1) A multilayer busbar for an immersion-cooling system, the multilayer busbar comprising: a multilayer base bar extending a first length; a multilayer riser extending a second length and being electrically coupled to the multilayer base bar; and a multilayer head extending a third length and being electrically coupled to the multilayer riser. Each of the multilayer base bar, the multilayer riser, and the multilayer head can comprise two or more conductive layers laminated together with insulating material located between adjacent conductive layers of the two or more conductive layers. The multilayer base bar can have a plurality of holes formed therein for making electrical contact to the two or more conductive layers of the multilayer base bar, and the multilayer head is configured to electrically couple to at least one power source.(2) The multilayer busbar of configuration (1), wherein: the multilayer base bar is configured to mount to a bottom of a tank of the immersion-cooling system; and the second length of the multilayer riser is long enough to place the multilayer head above coolant liquid in the tank when the immersion-cooling system is operating.(3) The multilayer busbar of configuration (1) or (2), wherein the second length of the multilayer riser is from approximately 200 mm to approximately 1500 mm.(4) The multilayer busbar of any one of configurations (1) through (3), wherein the third length of the multilayer head is long enough such that the multilayer head extends through an opening in a wall of the tank.(5) The multilayer busbar of any one of configurations (1) through (4), wherein: the two or more conductive layers of the multilayer base bar comprises a first conductive layer and a second conductive layer; and the plurality of holes comprises: a plurality of first holes each having a first diameter large enough to avoid electrical contact with first conductive layers of the two or more conductive layers in which the plurality of first holes are formed when a contact element is inserted through a selected first hole of the plurality of first holes; and a plurality of second holes each having a second diameter smaller than the first diameter to make electrical contact with second conductive layers of the two or more conductive layers in which the second holes are formed when the contact element is inserted through the selected first hole and into a selected second hole of the plurality of second holes.(6) The multilayer busbar of configuration (5), further comprising sockets installed in the plurality of second holes.(7) The multilayer busbar of configuration (5) or (6), wherein: the plurality of second holes are arranged in a regular pattern in the multilayer base bar; and a center-to-center spacing between adjacent holes of the plurality of second holes along a direction of the first length is from approximately 20 mm to approximately 100 mm.(8) The multilayer busbar of any one of configurations (5) through (7), wherein a diameter of each of the plurality of second holes is from approximately 5 mm to approximately 40 mm.(9) The multilayer busbar of any one of configurations (5) through (8), wherein the plurality of second holes are threaded.(10) The multilayer busbar of any one of configurations (5) through (8), further comprising pins or posts installed in the plurality of second holes.(11) The multilayer busbar of any one of configurations (1) through (10), wherein the two or more conductive layers consist of four conductive layers.(12) The multilayer busbar of configuration (11), wherein each conductive layer of the four conductive layers has a thickness from approximately I mm to approximately 2 mm.(13) The multilayer busbar of any one of configurations (1) through (12), wherein the first length of the multilayer base bar is from approximately 500 mm to approximately 2000 mm.(14) The multilayer busbar of any one of configurations (1) through (13), wherein a width of the multilayer base bar is from approximately 100 mm to approximately 500 mm.(15) The multilayer busbar of any one of configurations (1) through (14), wherein at least one conductive layer of the two or more conductive layers comprises copper or a copper alloy.(16) The multilayer busbar of any one of configurations (1) through (15), wherein at least one conductive layer of the two or more conductive layers comprises aluminum or an aluminum alloy.(17) The multilayer busbar of any one of configurations (1) through (16), wherein at least one conductive layer of the two or more conductive layers comprises silver or a silver alloy.(18) The multilayer busbar of any one of configurations (1) through (17), wherein at least one conductive layer of the two or more conductive layers comprises rhodium or a rhodium alloy.(19) The multilayer busbar of any one of configurations (1) through (18), wherein at least one conductive layer of the two or more conductive layers comprises zinc or a zinc alloy.(20) The multilayer busbar of any one of configurations (1) through (19), wherein at least one conductive layer of the two or more conductive layers comprises nickel or a nickel alloy.(21) The multilayer busbar of any one of configurations (1) through (20), wherein the insulating material comprises polyethylene terephthalate.(22) The multilayer busbar of any one of configurations (1) through (21), wherein the insulating material comprises polyimide.(23) The multilayer busbar of any one of configurations (1) through (22), wherein the insulating material comprises polycarbonate.(24) The multilayer busbar of any one of configurations (1) through (23), wherein the insulating material comprises polyethylene terephthalate.(25) The multilayer busbar of any one of configurations (1) through (24), wherein the insulating material comprises polyether ether ketone.(26) The multilayer busbar of any one of configurations (1) through (25), wherein the insulating material comprises an electrically insulating tape.(27) The multilayer busbar of any one of configurations (1) through (26), wherein the insulating material comprises an electrically insulating adhesive.(28) The multilayer busbar of any one of configurations (1) through (27), wherein the insulating material comprises a ceramic.(29) The multilayer busbar of any one of configurations (1) through (28), wherein the insulating material comprises a glass.(30) The multilayer busbar of any one of configurations (1) through (29), wherein the multilayer riser is oriented at a first angle with respect to the multilayer base bar, the first angle having a value from approximately 75 degrees to approximately 105 degrees.(31) The multilayer busbar of configuration (30), wherein a first width of the multilayer riser is approximately a same width as a second width of the multilayer base bar.(32) The multilayer busbar of configuration (30) or (31), wherein the multilayer head is oriented at a second angle with respect to the multilayer riser, the second angle having a value from approximately 75 degrees to approximately 105 degrees.(33) The multilayer busbar of any one of configurations (1) through (32), wherein a width of the multilayer head is from approximately 100 mm to approximately 500 mm.(34) The multilayer busbar of any one of configurations (1) through (33), wherein a length of the multilayer head is from approximately 100 mm to approximately 500 mm.(35) The multilayer busbar of any one of configurations (1) through (34), in combination with: a tank of the immersion-cooling system; and a feed-thru assembly configured to form a seal around an opening in a wall of the tank, the opening allowing for electrical coupling of the multilayer busbar to at least one power source located outside the tank.(36) The combination of (35), wherein the feed-thru assembly comprises: a compliant shell; a first sealing end connected to the compliant shell to form a first portion of the seal with the wall of the tank; and a second sealing end connected to the compliant shell to form a second portion of the seal with a mating flange.(37) The combination of (36), wherein: the mating flange is sealed to a multilayer power bar that couples to and provides electrical power to the multilayer busbar when the immersioncooling system is operating, and neither the multilayer head or the multilayer power bar contact the wall of the tank through which the opening is formed, such that the wall of the tank can move with respect to the multilayer head and the multilayer power bar when pressure within the tank changes.(38) The combination of (36) or (37), wherein the compliant shell, the first sealing end, and the second sealing end are molded from a same material.(39) The combination of any one of (36) through (38), wherein walls of the compliant shell are pleated or folded to allow compression of the compliant shell.(40) The combination of any one of (36) through (39), wherein at least the compliant shell comprises silicone.(41) The combination of any one of (36) through (38), wherein at least the compliant shell comprises nitrile rubber.(42) A method of receiving power from at least one power source for electronic components inside a tank of an immersion-cooling system, the method comprising receiving power on a multilayer busbar from a multilayer power bar, wherein the multilayer power bar is coupled to the at least one power source. The multilayer busbar comprises a multilayer base bar extending a first length; a multilayer riser extending a second length and being electrically coupled to the multilayer base bar; and a multilayer head extending a third length and being electrically coupled to the multilayer riser and to the multilayer power bar. Each of the multilayer base bar, the multilayer riser, and the multilayer head comprises two or more conductive layers laminated together with insulating material located between adjacent conductive layers of the two or more conductive layers. The multilayer base bar has a plurality of holes formed therein for making electrical connections between the electronic components and the two or more conductive layers. The method can further comprise distributing, from the multilayer base bar, the power received from the at least one power source to the electronic components.(43) The method of (42), wherein the multilayer head is located above a level of coolant liquid in the tank when the immersion-cooling system is operating.(44) The method of (42) or (43), further comprising: maintaining a seal around the multilayer head where the multilayer head passes through an opening in a wall of the tank while the wall of the tank moves during operation of the immersion-cooling system.(45) The method of (44), wherein the seal prevents vapor from leaking into an environment outside the tank.(46) The method of (44) or (45), wherein the seal prevents coolant liquid from leaking into an environment outside the tank.(47) The method of any one of (44) through (46), wherein the seal is maintained with a feed- thru assembly comprising: a compliant shell; a first sealing end connected to the compliant shell, wherein the first sealing end is configured to form a first portion of the seal with the wall of the tank; and a second sealing end connected to the compliant shell, wherein the second sealing end is configured to form a second portion of the seal with a mating piece.(48) The method of (47), wherein the mating piece comprises a flange.(49) The method of (47), wherein the mating piece comprises a tube.(50) The method of any one of (44) through (49), wherein the seal is maintained with a feed- thru assembly comprising: a casing extending around the multilayer head or around a multilayer power bar; and one or more O-rings disposed between the casing and the multilayer head or between the casing and the multilayer power bar.(51) A feed-thru assembly to maintain a seal around electrical conductors that pass through an opening in a wall of a tank of an immersion-cooling system, the feed-thru assembly comprising: a compliant shell; a first sealing end connected to the compliant shell, wherein the first sealing end is configured to form a first portion of the seal with the wall of the tank or with a fixture onthe wall of the tank; and a second sealing end connected to the compliant shell, wherein the second sealing end is configured to form a second portion of the seal with a mating piece, wherein the compliant shell is configured to maintain the seal while allowing motion of the wall with respect to the electrical conductors.(52) The feed-thru assembly of configuration (51), wherein at least one of the first sealing end and the second sealing end is flanged.(53) The feed-thru assembly of configuration (51), wherein at least one of the first sealing end and the second sealing end is tubular.(54) The feed-thru assembly of any one of configurations (51) through (53), further comprising: a first flange plate to clamp the first sealing end against the wall of the tank; and a second flange plate to clamp the second sealing end against a flange of the mating piece.(55) The feed-thru assembly of any one of configurations (51) through (53), wherein the compliant shell comprises silicone.(56) The feed-thru assembly of any one of configurations (51) through (53), wherein the compliant shell comprises nitrile rubber.(57) The feed-thru assembly of any one of configurations (51) through (56), wherein the compliant shell, the first sealing end, and the second sealing end are molded from a same material.(58) The feed-thru assembly of any one of configurations (51) through (57), wherein the compliant shell comprises walls that are pleated or are folded in a form of accordion bellows.(59) A busbar for an immersion-cooling system, the busbar comprising: a base bar extending a first length; a riser extending a second length and being electrically coupled to the base bar; and a head extending a third length and being electrically coupled to the riser, wherein: each of the base bar, the riser, and the head comprises two conductive elements separated by a distance, the two conductive elements extend adjacent to each other, the base bar has a plurality of holes formed therein for making electrical contact to the two conductive elements of the base bar, and the head is configured to electrically couple to a power source.(60) The busbar of configuration (59), wherein: the base bar is configured to mount to a bottom of a tank of the immersion-cooling system; and the second length of the riser is long enough to place the head above coolant liquid in the tank when the immersion-cooling system is operating.

[0081] 5. Conclusion

[0082] While various inventive embodiments have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and / or structures for performing the function and / or obtaining the results and / or one or more of the advantages described herein, and each of such variations and / or modifications is deemed to be within the scopeof the inventive embodiments described herein. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and / or configurations will depend upon the specific application or applications for which the inventive teachings is / are used. Those skilled in the art will recognize or be able to ascertain, using no more than routine experimentation, many equivalents to the specific inventive embodiments described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that inventive embodiments may be practiced otherwise than as specifically described. Inventive embodiments of the present disclosure are directed to each individual feature, system, article, material, kit, and / or method described herein. In addition, any combination of two or more such features, systems, articles, materials, kits, and / or methods, if such features, systems, articles, materials, kits, and / or methods are not mutually inconsistent, is included within the inventive scope of the present disclosure.

[0083] Also, various inventive concepts may be embodied as one or more methods, of which an example has been provided. The acts performed as part of the method may be ordered in any suitable way. Accordingly, embodiments may be constructed in which acts are performed in an order different than illustrated, which may include performing some acts simultaneously, even though shown as sequential acts in illustrative embodiments.

[0084] All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and / or ordinary meanings of the defined terms.100851 Unless stated otherwise, the terms “approximately” and “about” are used to mean within ± 20% of a target (e.g., dimension or orientation) in some embodiments, within ± 10% of a target in some embodiments, within ± 5% of a target in some embodiments, and yet within ± 2% of a target in some embodiments. The terms “approximately” and “about” can include the target. The term “essentially” is used to mean within ± 3% of a target.

[0086] The indefinite articles “a” and “an,” as used herein, unless clearly indicated to the contrary, should be understood to mean “at least one.”

[0087] The phrase “and / or,” as used herein, should be understood to mean “either or both” of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Multiple elements listed with “and / or” should be construed in the same fashion, i.e., “one or more” of the elements so conjoined. Other elements may optionally be present other than the elements specifically identified by the “and / or” clause, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, a reference to “A and / or B”, when used in conjunction with open-ended language such as “comprising” can refer, in one embodiment, to A only (optionally including elements other than B); in another embodiment, to B only (optionally including elements other than A); in yet another embodiment, to both A and B (optionally including other elements); etc.

[0088] As used herein, “or” should be understood to have the same meaning as “and / or” as defined above. For example, when separating items in a list, “or” or “and / or” shall be interpreted as being inclusive, i.e., the inclusion of at least one, but also including more than one, of a number or list of elements, and, optionally, additional unlisted items. Only terms clearly indicated to the contrary, such as “only one of’ or “exactly one of’ or “consisting of,” will refer to the inclusion of exactly one element of a number or list of elements. In general, the term “or” as used herein shall only be interpreted as indicating exclusive alternatives (i.e., “one or the other but not both”) when preceded by terms of exclusivity, such as “either,” “one of,” “only one of,” or “exactly one of.” “Consisting essentially of,” shall have its ordinary meaning as used in the field of patent law.

[0089] As used herein, the phrase “at least one,” in reference to a list of one or more elements, should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of each and every element specifically listed within the list of elements and not excluding any combinations of elements in the list of elements. This definition also allows that elements may optionally be present other than the elements specifically identified within the list of elements to which the phrase “at least one” refers, whether related or unrelated to those elements specifically identified. Thus, as a nonlimiting example, “at least one of A and B” (or, equivalently, “at least one of A or B,” or, equivalently “at least one of A and / or B”) can refer, in one embodiment, to at least one, optionally including more than one, A, with no B present (and optionally including elements other than B); in another embodiment, to at least one, optionally including more than one, B, with no A present (and optionally including elements other than A); in yet another embodiment, to at least one, optionally including more than one, A, and at least one, optionally including more than one, B (and optionally including other elements); etc.

[0090] In the specification above, all transitional phrases such as “comprising,” “including,” “carrying,” “having,” “containing,” “involving,” “holding,” “composed of,” and the like are to be understood to be open-ended, i.e., to mean including but not limited to. Only the transitional phrases “consisting of’ and “consisting essentially of’ shall be closed or semi-closed transitional phrases, respectively, as set forth in the United States Patent Office Manual of Patent Examining Procedures, Section 2111.03.What is claimed is:

Claims

CLAIMS1 . A multilayer busbar for an immersion-cooling system, the multilayer busbar comprising: a multilayer base bar extending a first length; a multilayer riser extending a second length and being electrically coupled to the multilayer base bar; and a multilayer head extending a third length and being electrically coupled to the multilayer riser, wherein: each of the multilayer base bar, the multilayer riser, and the multilayer head comprises two or more conductive layers laminated together with insulating material located between adjacent conductive layers of the two or more conductive layers, the multilayer base bar has a plurality of holes formed therein for making electrical contact to the two or more conductive layers of the multilayer base bar, and the multilayer head is configured to electrically couple to at least one power source.

2. The multilayer busbar of claim 1 , wherein: the multilayer base bar is configured to mount to a bottom of a tank of the immersioncooling system; and the second length of the multilayer riser is long enough to place the multilayer head above coolant liquid in the tank when the immersion-cooling system is operating.

3. The multilayer busbar of claim 2, wherein the second length of the multilayer riser is from approximately 200 mm to approximately 1500 mm.

4. The multilayer busbar of claim 2, wherein the third length of the multilayer head is long enough such that the multilayer head extends through an opening in a wall of the tank.

5. The multilayer busbar of claim 1, wherein: the two or more conductive layers of the multilayer base bar comprises a first conductive layer and a second conductive layer; and the plurality of holes comprises: a plurality of first holes each having a first diameter large enough to avoid electrical contact with first conductive layers of the two or more conductive layers in which the plurality of first holes are formed when a contact element is inserted through a selected first hole of the plurality of first holes; and a plurality of second holes each having a second diameter smaller than the first diameter to make electrical contact with second conductive layers of the two or more conductive layers in which the second holes are formed when the contact element is inserted through the selected first hole and into a selected second hole of the plurality of second holes.

6. The multilayer busbar of claim 5, further comprising sockets installed in the plurality of second holes.

7. The multilayer busbar of claim 5, wherein: the plurality of second holes are arranged in a regular pattern in the multilayer base bar; and a center-to-center spacing between adjacent holes of the plurality of second holes along a direction of the first length is from approximately 20 mm to approximately 100 mm.

8. The multilayer busbar of claim 5, wherein a diameter of each of the plurality of second holes is from approximately 5 mm to approximately 40 mm.

9. The multilayer busbar of claim 5, wherein the plurality of second holes are threaded.

10. The multilayer busbar of claim 5, further comprising pins or posts installed in the plurality of second holes.

11. The multilayer busbar of any one of claims 1 through 10, wherein the two or more conductive layers consist of four conductive layers.

12. The multilayer busbar of claim 11, wherein each conductive layer of the four conductive layers has a thickness from approximately 1 mm to approximately 2 mm.

13. The multilayer busbar of any one of claims 1 through 10, wherein the first length of the multilayer base bar is from approximately 500 mm to approximately 2000 mm.

14. The multilayer busbar of any one of claims 1 through 10, wherein a width of the multilayer base bar is from approximately 100 mm to approximately 500 mm.

15. The multilayer busbar of any one of claims 1 through 10, wherein at least one conductive layer of the two or more conductive layers comprises copper or a copper alloy.

16. The multilayer busbar of any one of claims 1 through 10, wherein at least one conductive layer of the two or more conductive layers comprises aluminum or an aluminum alloy.

17. The multilayer busbar of any one of claims 1 through 10, wherein at least one conductive layer of the two or more conductive layers comprises silver or a silver alloy.

18. The multilayer busbar of any one of claims 1 through 10, wherein at least one conductive layer of the two or more conductive layers comprises rhodium or a rhodium alloy.

19. The multilayer busbar of any one of claims 1 through 10, wherein at least one conductive layer of the two or more conductive layers comprises zinc or a zinc alloy.

20. The multilayer busbar of any one of claims 1 through 10, wherein at least one conductive layer of the two or more conductive layers comprises nickel or a nickel alloy.

21. The multilayer busbar of any one of claims 1 through 10, wherein the insulating material comprises polyethylene terephthalate.

22. The multilayer busbar of any one of claims 1 through 10, wherein the insulating material comprises polyimide.

23. The multilayer busbar of any one of claims 1 through 10, wherein the insulating material comprises polycarbonate.

24. The multilayer busbar of any one of claims 1 through 10, wherein the insulating material comprises polyethylene terephthalate.

25. The multilayer busbar of any one of claims 1 through 10, wherein the insulating material comprises polyether ether ketone.

26. The multilayer busbar of any one of claims 1 through 10, wherein the insulating material comprises an electrically insulating tape.

27. The multilayer busbar of any one of claims 1 through 10, wherein the insulating material comprises an electrically insulating adhesive.

28. The multilayer busbar of any one of claims 1 through 10, wherein the insulating material comprises a ceramic.

29. The multilayer busbar of any one of claims 1 through 10, wherein the insulating material comprises a glass.

30. The multilayer busbar of any one of claims 1 through 10, wherein the multilayer riser is oriented at a first angle with respect to the multilayer base bar, the first angle having a value from approximately 75 degrees to approximately 105 degrees.

31. The multilayer busbar of claim 30, wherein a first width of the multilayer riser is approximately a same width as a second width of the multilayer base bar.

32. The multilayer busbar of claim 30, wherein the multilayer head is oriented at a second angle with respect to the multilayer riser, the second angle having a value from approximately 75 degrees to approximately 105 degrees.

33. The multilayer busbar of any one of claims 1 through 10, wherein a width of the multilayer head is from approximately 100 mm to approximately 500 mm.

34. The multilayer busbar of any one of claims 1 through 10, wherein a length of the multilayer head is from approximately 100 mm to approximately 500 mm.

35. The multilayer busbar of any one of claims 1 and 5 through 10, in combination with: a tank of the immersion-cooling system; and a feed-thru assembly configured to form a seal around an opening in a wall of the tank,the opening allowing for electrical coupling of the multilayer busbar to at least one power source located outside the tank.

36. The combination of claim 35, wherein the feed-thru assembly comprises: a compliant shell; a first sealing end connected to the compliant shell to form a first portion of the seal with the wall of the tank; and a second sealing end connected to the compliant shell to form a second portion of the seal with a mating flange.

37. The combination of claim 36, wherein: the mating flange is sealed to a multilayer power bar that couples to and provides electrical power to the multilayer busbar when the immersion-cooling system is operating, and neither the multilayer head or the multilayer power bar contact the wall of the tank through which the opening is formed, such that the wall of the tank can move with respect to the multilayer head and the multilayer power bar when pressure within the tank changes.

38. The combination of claim 36, wherein the compliant shell, the first sealing end, and the second sealing end are molded from a same material.

39. The combination of claim 36, wherein walls of the compliant shell are pleated or folded to allow compression of the compliant shell.

40. The combination of claim 36, wherein at least the compliant shell comprises silicone.

41. The combination of claim 36, wherein at least the compliant shell comprises nitrile rubber.

42. A method of receiving power from at least one power source for electronic components inside a tank of an immersion-cooling system, the method comprising: receiving power on a multilayer busbar from a multilayer power bar, wherein the multilayer power bar is coupled to the at least one power source; wherein the multilayer busbar comprises: a multilayer base bar extending a first length; a multilayer riser extending a second length and being electrically coupled to the multilayer base bar; and a multilayer head extending a third length and being electrically coupled to the multilayer riser and to the multilayer power bar, wherein: each of the multilayer base bar, the multilayer riser, and the multilayer head comprises two or more conductive layers laminated together with insulating material located between adjacent conductive layers of the two or more conductive layers, and the multilayer base bar has a plurality of holes formed therein for making electrical connections between the electronic components and the two or more conductive layers; anddistributing, from the multilayer base bar, the power received from the at least one power source to the electronic components.

43. The method of claim 42, wherein the multilayer head is located above a level of coolant liquid in the tank when the immersion-cooling system is operating.

44. The method of claim 42 or claim 43, further comprising: maintaining a seal around the multilayer head where the multilayer head passes through an opening in a wall of the tank while the wall of the tank moves during operation of the immersion-cooling system.

45. The method of claim 44, wherein the seal prevents vapor from leaking into an environment outside the tank.

46. The method of claim 44, wherein the seal prevents coolant liquid from leaking into an environment outside the tank.

47. The method of claim 44, wherein the seal is maintained with a feed-thru assembly comprising: a compliant shell; a first sealing end connected to the compliant shell, wherein the first sealing end is configured to form a first portion of the seal with the wall of the tank; and a second sealing end connected to the compliant shell, wherein the second sealing end is configured to form a second portion of the seal with a mating piece.

48. The method of claim 47, wherein the mating piece comprises a flange.

49. The method of claim 47, wherein the mating piece comprises a tube.

50. The method of claim 44, wherein the seal is maintained with a feed-thru assembly compri sing: a casing extending around the multilayer head or around a multilayer power bar; and one or more O-rings disposed between the casing and the multilayer head or between the casing and the multilayer power bar.

51. A feed-thru assembly to maintain a seal around electrical conductors that pass through an opening in a wall of a tank of an immersion-cooling system, the feed-thru assembly comprising: a compliant shell; a first sealing end connected to the compliant shell, wherein the first sealing end is configured to form a first portion of the seal with the wall of the tank or with a fixture on the wall of the tank; and a second sealing end connected to the compliant shell, wherein the second sealing end is configured to form a second portion of the seal with a mating piece, wherein the compliant shell is configured to maintain the seal while allowing motion of the wall with respect to the electrical conductors.

52. The feed-thru assembly of claim 1, wherein at least one of the first sealing end and the second sealing end is flanged.

53. The feed-thru assembly of claim 51, wherein at least one of the first sealing end and the second sealing end is tubular.

54. The feed-thru assembly of claim 51, further comprising: a first flange plate to clamp the first sealing end against the wall of the tank; and a second flange plate to clamp the second sealing end against a flange of the mating piece.

55. The feed-thru assembly of claim 51 , wherein the compliant shell comprises silicone.

56. The feed-thru assembly of claim 1, wherein the compliant shell comprises nitrile rubber.

57. The feed-thru assembly of any one of claims 51 through 56, wherein the compliant shell, the first sealing end, and the second sealing end are molded from a same material.

58. The feed-thru assembly of any one of claims 1 through 56, wherein the compliant shell comprises walls that are pleated or are folded in a form of accordion bellows.

59. A busbar for an immersion-cooling system, the busbar comprising: a base bar extending a first length; a riser extending a second length and being electrically coupled to the base bar; and a head extending a third length and being electrically coupled to the riser, wherein: each of the base bar, the riser, and the head comprises two conductive elements separated by a distance, the two conductive elements extend adjacent to each other, the base bar has a plurality of holes formed therein for making electrical contact to the two conductive elements of the base bar, and the head is configured to electrically couple to a power source.

60. The busbar of claim 59, wherein: the base bar is configured to mount to a bottom of a tank of the immersion-cooling system; and the second length of the riser is long enough to place the head above coolant liquid in the tank when the immersion-cooling system is operating.

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