阅读说明：本技术 高功率和高能量密度电池备用单元电芯封装设计 (High power and high energy density battery backup unit cell packaging design ) 是由 杨华威 高天翼 于 2020-08-04 设计创作，主要内容包括：本发明涉及一种数据中心的电子机架的电池备用单元(BBU)模块、一种BBU搁架和一种电子机架。BBU模块包括电芯包,其中具有多个电池电芯,电芯包的尺寸被设计成适于装配在电子机架的一个机架单位(1RU)的高度和电子机架的三分之一的搁架宽度内。多个电池电芯被布置成使得每个电池电芯具有水平且平行于电子机架前部的纵向轴线。多个电池电芯被布置成十四个组,每组六个电池电芯,十四个组串联连接,每组中的六个电池电芯并联连接。十四个组在电芯包中被布置成宽度上两个组、高度上一个组和深度上七个组。每组中的六个电池电芯被布置为上排三个电池电芯深和下排三个电池电芯深。(The invention relates to a Battery Backup Unit (BBU) module of an electronic rack of a data center, a BBU shelf and an electronic rack. The BBU module includes a battery core package having a plurality of battery cells therein, the battery core package being sized to fit within one rack unit (1RU) of the electronics rack and one-third of the rack width of the electronics rack. The plurality of battery cells are arranged such that each battery cell has a longitudinal axis that is horizontal and parallel to the front of the electronics rack. The plurality of battery cells are arranged in fourteen groups of six battery cells, the fourteen groups being connected in series, the six battery cells in each group being connected in parallel. Fourteen groups are arranged in the cell pack into two groups in width, one group in height and seven groups in depth. The six battery cells in each group are arranged three battery cells deep in the upper row and three battery cells deep in the lower row.)

1. A Battery Backup Unit (BBU) module of an electronics rack of a data center, the BBU module comprising:

a battery pack having a plurality of battery cells therein, the battery pack sized to fit within a height of one rack unit (1RU) of an electronics rack and a shelf width of one-third of the electronics rack,

wherein the plurality of battery cells are arranged such that each battery cell has a longitudinal axis that is horizontal and parallel to the front of the electronics rack,

wherein the plurality of battery cells are arranged in fourteen groups of six battery cells, the fourteen groups being connected in series, the six battery cells in each group being connected in parallel,

wherein the fourteen groups are arranged in the electrical core package in two groups in width, one group in height, and seven groups in depth, and

wherein the six battery cells in each group are arranged three battery cells deep in an upper row and three battery cells deep in a lower row.

2. The BBU module of claim 1, wherein the cell pack includes two battery cells in width, two battery cells in height, and twenty-one battery cells in depth for a total of eighty-four battery cells.

3. The BBU module of claim 1 or 2, wherein the plurality of battery cells in the battery core package includes four battery cells in a rectangular arrangement.

4. The BBU module of claim 1 or 2, wherein the plurality of battery cells in the battery core package includes an upper pair of battery cells interleaved with a lower pair of battery cells.

5. The BBU module of claim 1 or 2, wherein the six battery cells in a group include three upper battery cells interleaved with three lower battery cells.

6. The BBU module of claim 1 or 2, wherein the six battery cells in a group include three upper and three lower battery cells in a rectangular arrangement.

7. The BBU module of claim 1 or 2, wherein said battery-spare unit modules are dimensioned such that nine instances of said battery-spare unit modules fit in three rack units (3RU) of said electronics rack, three by three.

8. The BBU module of claim 1 or 2, wherein the cells include a battery management system module and one or more fans.

9. The BBU module of claim 1 or 2, wherein the electrical core package includes a housing having a bore for air cooling, and wherein the plurality of battery cells are spaced apart for the air cooling.

10. A Battery Backup Unit (BBU) shelf of an electronics rack of a data center, the BBU shelf comprising:

a plurality of BBU modules according to any one of claims 1 to 9,

wherein the BBU shelf is configured to be inserted into any of the standard shelves of an electronics rack.

11. An electronics rack, comprising:

a plurality of rack shelves, at least one of the rack shelves configured to receive a server shelf having one or more servers therein, wherein each server comprises one or more processors and memory for storing instructions that, when executed by the one or more processors, cause the processors to perform data processing operations;

a power supply unit configured to supply power to the server; and

a Battery Backup Unit (BBU) shelf inserted in one of the rack shelves, the BBU shelf including one or more BBU modules according to any one of claims 1-9.

Technical Field

The invention relates to a Battery Backup Unit (BBU) module of an electronic rack of a data center, a BBU shelf and an electronic rack.

Background

For data center and IT (information technology) equipment applications, batteries are often used as battery backup power sources or energy storage devices. Battery Backup Units (BBUs) are extremely important and essential in data centers. IT (information technology) and cloud companies devote significant resources on BBUs to ensure that sufficient energy is stored for energy backup purposes when the grid is powered down, so that no service interruption occurs. It is important to reduce down time as much as possible. In addition to data center applications, battery energy storage is also critical in electric vehicles (including autonomous driving). Battery storage is very important and is currently the only way to power electric vehicles.

The design and operation of Battery Backup Units (BBUs) need to follow and meet critical requirements, including power and energy redundancy of distribution areas within standard racks. Cooling the part is also challenging because skin temperature is an important factor affecting battery operating conditions, including battery charge and discharge power, stored energy, battery health and degradation. An industry standard battery backup unit module has fourteen groups of series connected batteries, each group of four parallel battery cells (battery cells), referred to as 14S 4P. So many requirements limit the size, power, cooling, redundancy, modularity, etc. and so many possible combinations of parallel and series cells, it is not a simple and intuitive matter to retrofit an industry standard 14S 4P battery backup unit. It is under these conditions that the present embodiment was developed.

Disclosure of Invention

The invention provides a Battery Backup Unit (BBU) module of an electronic rack of a data center, a BBU shelf and an electronic rack.

In a first aspect, the present invention provides a Battery Backup Unit (BBU) module for an electronics rack of a data center. The BBU module includes an electrical core package having a plurality of battery cells therein, the electrical core package sized to fit within one rack unit (1RU) height of an electronics rack and one-third of a rack width of the electronics rack, wherein the plurality of battery cells are arranged such that each battery cell has a longitudinal axis that is horizontal and parallel to the front of the electronics rack, wherein the plurality of battery cells are arranged in fourteen groups of six battery cells, the fourteen groups being connected in series, the six battery cells in each group being connected in parallel, wherein the fourteen groups are arranged in the electrical core package in two groups in width, one group in height, and seven groups in depth, and wherein the six battery cells in each group are arranged three battery cells deep in an upper row and three battery cells deep in a lower row.

In some embodiments, the cell pack includes two battery cells in width, two battery cells in height, and twenty-one battery cells in depth for a total of eighty-four battery cells.

In some embodiments, the plurality of battery cells in the battery core package includes four battery cells in a rectangular arrangement.

In some embodiments, the plurality of battery cells in the battery core package includes an upper pair of battery cells interleaved with a lower pair of battery cells.

In some embodiments, the six battery cells in a group include three upper battery cells interleaved with three lower battery cells.

In some embodiments, the six battery cells in a group include three upper battery cells and three lower battery cells in a rectangular arrangement.

In some embodiments, the battery backup unit modules are sized such that nine instances of the battery backup unit modules fit three by three in three rack units (3RU) of the electronics rack.

In some embodiments, the cell pack includes a battery management system module and one or more fans.

In some embodiments, the battery cell includes a housing having an aperture for air cooling, and wherein the plurality of battery cells are spaced apart for the air cooling.

In a second aspect, the invention provides a Battery Backup Unit (BBU) shelf of an electronics rack of a data center, the BBU shelf comprising a plurality of BBU modules as described in accordance with the first aspect, wherein the BBU shelf is configured to be inserted into any of the standard shelves of the electronics rack.

In a third aspect, the present invention provides an electronics rack comprising a plurality of rack shelves, a power supply unit, and a Battery Backup Unit (BBU) shelf. At least one of the rack shelves is configured to receive a server shelf having one or more servers therein, wherein each server includes one or more processors and memory for storing instructions that, when executed by the one or more processors, cause the processors to perform data processing operations. The power supply unit is configured to supply power to the server. A Battery Backup Unit (BBU) shelf is inserted in one of the rack shelves, the BBU shelf including one or more BBU modules as described according to the first aspect.

Drawings

The described embodiments and their advantages are best understood by referring to the following description in conjunction with the accompanying drawings. These drawings in no way limit any changes in form and detail to the described embodiments for those skilled in the art without departing from the spirit and scope of the described embodiments.

Fig. 1A depicts an embodiment of a Battery Backup Unit (BBU) module having example dimensions, according to one embodiment of the present disclosure.

Fig. 1B depicts a set of six battery cells in an arrangement for the BBU module of fig. 1A as a 6P set.

Fig. 2A is a front view layout 1 showing battery cells projected to the front of the BBU module of fig. 1A.

Fig. 2B is a front view layout 2 showing battery cells projected to the front of the BBU module of fig. 1A.

Fig. 3 is a side view layout 1 showing one 6P group of battery cells projected to the side of the BBU module of fig. 1A.

Fig. 4 is a side view layout 2 showing one 6P group of battery cells projected to the side of the BBU module of fig. 1A.

Fig. 5 is a side view depicting seven sets of six cells projected to the side of the BBU module of fig. 1A in one embodiment.

Fig. 6 is a top view of a BBU module in one embodiment, depicting a left-hand arrangement of seven 6P groups and a right-hand arrangement of seven 6P groups in a cell pack that also includes a Battery Management System (BMS) module, a fan, and possibly other components.

Fig. 7 shows a series electrical connection of fourteen groups of cells, six batteries being connected in parallel in each 6P group.

Fig. 8 shows nine BBUs as one Battery Backup System (BBS), arranged as 3 × 3.

FIG. 9 is a flow diagram of a design logic method for designing embodiments of BBU modules and BBSs.

Fig. 10 is a block diagram illustrating an example of an electronics rack, according to one embodiment.

Detailed Description

Various embodiments and aspects of the disclosure will be described with reference to details discussed below, and the accompanying drawings will illustrate the various embodiments. The following description and drawings are illustrative of the present disclosure and are not to be construed as limiting the present disclosure. Numerous specific details are described to provide a thorough understanding of various embodiments of the present disclosure. However, in certain instances, well-known or conventional details are not described in order to provide a concise discussion of embodiments of the present disclosure.

Reference in the specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the disclosure. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment.

An industry standard Battery Backup Unit (BBU) module, abbreviated or designated 14S 4P, has fourteen banks in series, with four battery cells in parallel in each bank. Embodiments of the BBU module described herein improve the industry standard 14S 4P BBU and provide an optimal solution to achieve high power and high energy density BBU in a rack requiring only 1 rack unit (1RU), with an output power of at least 4.5kW and an energy of at least 375Wh at such power. The power and energy may vary depending on the output power and the different battery cells selected. At least 84 18650 cells can be accommodated in the proposed BBU, which makes it different from most BBU designs, which cannot accommodate so many cells with the required power and energy density at a height of 1 RU.

Battery storage for data centers and residential areas is a possible application of BBU embodiments. Battery storage is important for energy storage and backup purposes, including but not limited to data center energy backup units, power utility backup and peak shaving, electric vehicles (including autonomous driving), aerospace, and the like. This design is optimal in terms of power, energy and thermal performance. It will extend service life and reduce cost compared to other designs.

Embodiments of the present disclosure include BBU electrical core package designs that can meet the high power and energy density requirements of high power server racks. The BBU module internally comprises 84 18650 cells, wherein 6 cells are connected in parallel to form a group, and then 14 groups are connected in series. The height of the BBU module is 1 machine frame unit, the minimum height can reach 44.45 millimeters, but the BBU module can be expanded to a higher degree according to different machine frames, so that the BBU module has universality. The width is 170 mm. The BBU module is modular in design so that multiple BBU modules can be combined together to form a Battery Backup System (BBS) that can be mounted in an electronics rack, such as a server rack or a data center rack.

The battery cell layout can accommodate almost all high power 18650 battery cells on the market to achieve the desired high power and energy density. BBU is a modular design that can be stacked to meet various power and energy requirements, e.g., at different power levels of 15kW, 20kW, for different standby times. BBU mechanical dimensions are applicable to most data center racks and are available as standard configurations. The proposed BBU can provide optimized thermal performance such that at the required high power and energy density, battery degradation can be minimized without reaching over-temperature conditions. Based on the balance of cell characteristics, high power and energy density, the cell pack can provide the best electrical performance, and 6 cells are placed in parallel in a rack unit height. This is an optimal design based on a rack-level energy backup solution. This design provides more possibilities for fan/fan system design and selection to accommodate different thermal conditions.

Embodiments of a Battery Backup Unit (BBU) module are described. The BBU is provided with a battery core package, and a plurality of battery cells are arranged in the battery core package. The electrical core package is sized to fit within one rack unit (1RU) of the electronics rack and one-third of the rack width of the electronics rack. The battery cells are arranged such that each battery cell has a longitudinal axis that is horizontal and parallel to the front of the electronics rack. The battery cells are arranged in 14 groups of six cell cells each. The 14 groups are connected in series. Six battery cells in each group are connected in parallel. This arrangement is referred to as 14S 6P. In the cell pack, the 14 groups are arranged in two groups in width, one group in height, and seven groups in depth. The six battery cells in each group are arranged three battery cells deep in the upper row and three battery cells deep in the lower row.

Embodiments of an electronics rack are described. The electronics rack has a battery backup unit shelf with one or more BBU modules. Each BBU module has a battery core package that fits within one rack unit of height and one third of the shelf width. The battery core package has a plurality of battery cells. Each battery cell is oriented parallel to the front of the electronics rack and the front of the cell pack. The battery cells are oriented parallel to the shelves of the electronics rack and the top of the cell pack. The battery cells are divided into 14 groups of battery cells. The battery cells in each group are connected in parallel. The battery cell groups are connected in series. Each group in the battery core group is used as six battery cells and is arranged to be three cells deep at the upper row and three cells deep at the lower row. The battery pack has groups of battery cells arranged in two groups across the width of the pack, one group across the height of the pack, and seven groups across the depth of the pack.

Fig. 1A depicts an embodiment of a Battery Backup Unit (BBU) module 100 having example dimensions according to the present disclosure. Height 43.5 mm, fit in 1RU, but may vary in another embodiment. A width of 170 millimeters, fitting within one third of the width of the electronics rack, allowing three BBUs to be placed side-by-side across the width of the electronics rack. The length is 660 mm, and the rack can be placed in the depth of most racks in the global market, such as OCP V1-V3 racks, ODCC Scorpion V2 racks and Beiji V3 racks.

As described further below, the battery cells in the BBU module 100 comprise a pack of six battery cells. Viewed from the front 104, top 102, and sides 106 of the BBU modules 100, the BBU modules 100 are one set 108 high, two sets 108 wide, and seven sets 108 deep. That is, there are two groups of 108 cells in the width of the cell package and the BBU module 100, one group of 108 cells in the height of the cell package and the BBU module 100, and seven groups of 108 cells in the depth of the cell package and the BBU module 100.

Fig. 1B depicts a group 108 of six battery cells in an arrangement for the BBU module 100 of fig. 1A as a 6P group 108. All of the cells 202 are parallel to the front and top of the pack 108, and also parallel to the front 104 and top 102 of the BBU module 100. All of the cells 202 are perpendicular to the sides of the pack 108, and also perpendicular to the sides 106 of the BBU module 100. The cells in the group 108 are arranged in a top row 110 of three cells side-by-side (i.e., the depth of three cells) and a bottom row 112 of three cells side-by-side (i.e., the depth of three cells).

Fig. 2A is a front view layout 1 showing battery cells 202 projected onto the front 104 of the BBU module 100 of fig. 1A. The two cells 202 on the left belong to one group 108, and the two cells 202 on the right belong to another group 108 (see also fig. 6). Four cells 202 can be seen, each approximately 65 millimeters long, transverse to the front 104 of the BBU module 100 (i.e., the longitudinal axes of the cells 200 are transverse or parallel to the front 104 of the BBU module 100). A. B, C and D are dimensions that hold the cell 202 inside, where A is no greater than 2 mm, B is no greater than 34 mm, C is no less than 1.5 mm, and D is no greater than 1.5 mm.

Fig. 2B is a front view layout 2 showing battery cells 202 projected onto the front portion 104 of the BBU module 100 of fig. 1A. Layout 2 changes the horizontal distance E between two cells 202 to give more flexibility, where E has only a minimum requirement, i.e., E is not less than 1.5 millimeters. Another feature of layout 2 is that the upper cells 202 are staggered with respect to the lower cells 202. Various amounts of staggering to the left or right may be employed.

Fig. 3 is a side view layout 1 showing battery cells 202 of one 6P group 108 projected onto the side portion 106 of the BBU module 100 of fig. 1A. There are six cells 202 in a group 108, and all six cells 202 of the group 108 are electrically connected in parallel. In layout 1, in various embodiments, the vertical angle between two cells may vary from 30 degrees to 45 degrees, with the upper cells 202 staggered relative to the lower cells 202, and vice versa.

Fig. 4 is a side view layout 2 showing battery cells 202 of one 6P group 108 projected onto the side 106 of the BBU module 100 of fig. 1A. Here, in the side view layout 2, the upper cell 202 is located directly above the lower cell 202, i.e., has an angle of 0 degrees compared to the 30 to 45 degrees of the side view layout 1. The various side view layouts of fig. 3 and 4 may be blended with the various front view layouts of fig. 2A and 2B in various combinations, which may be useful for airflow fine tuning in air cooling.

Fig. 5 is a side view depicting seven groups 108 of six cells 202, each projected to the side 106 of the BBU module 100 of fig. 1A, in one embodiment. If viewed from the top 102 of the BBU module 100, there are a total of 7 groups 108 on one side (left or right). See fig. 6 for a top view. Viewed from the side 106 of the BBU module 100, there is one lower row of 21 cells 202, two cells 202 deep, and one upper row of 21 cells 202, also two cells 202 deep, in the BBU module 100 for a total of 84 cells 202.

Fig. 6 is a top view of BBU module 100 depicting a left side 610 arrangement of seven 6P groups 108 and a right side 612 arrangement of seven 6P groups 108 in a cell pack 608, the cell pack 608 further including a Battery Management System (BMS) module 602, one or more fans 604, and possibly other components, in one embodiment. The length of one electrical core package 608 is 418.50 millimeters. As described above, there are eighty-four cells 202, with six cells 202 in each of the fourteen groups 108. In this top view, only the upper three cells 202 in each group 108 are seen.

Fig. 7 illustrates a series electrical connection of fourteen groups 108 of cells 202, with six cells 202 in each 6P group 108 connected in parallel. This arrangement and electrical connection of the BBU module 100 is referred to as 14S 6P. This one BBU module can be stacked with other modules to form one Backup Battery System (BBS) of multiple BBU modules 100. Fig. 8 shows an example of stacking.

Fig. 8 shows nine BBU modules 100 arranged as a 3 × 3 (or 3 by 3, i.e., three rows of three, three each) as one Backup Battery System (BBS) 802. This arrangement occupies three rack units (3 RU). Other arrangements are also possible, such as a 2 × 3 (two rows of three each) BBS occupying two rack units (2RU), a 1 × 3 (one row of three each) BBS occupying one rack unit (1RU), a 4 × 3 (four rows of three each) occupying four rack units (4RU), a 5 × 3 (five rows of three each) occupying five rack units (5RU), and so forth.

The mechanical design of the BBU module 100 is explained above. The BBU module may have a electrical core package and other components, including the BMS module, one or more fans, and other peripherals. The cell pack design in the above embodiment is optimal in terms of electricity, heat and cost to meet the high power requirements of from 10kW to 40kW in the rack for a certain standby time. The design principle is to find the optimum power and energy density in the cell package/BBU that meets the thermal requirements of the battery cells while having reasonable N +1 redundancy.

Electrical considerations are discussed below. For a 21 inch/538 mm wide rack, the maximum number of standard 18650 cells that can be placed in a group in parallel is determined to be six per unit, taking into account the reasonable space for the connections and closures of the layouts in fig. 2A and 2B. Thus, to meet high power requirements, e.g., 4.5kW per BBU module, and the longer standby time for currently available battery cells, 6P is the best choice. For such high currents, a 3P design is not feasible, and 4P would require too much current per cell, so the standby time is significantly shortened. A 5P design is feasible but does not give sufficient margin after cell degradation. Above 6P to 7P, and 8P, they may not fit in all racks because the number of cells increases and the required depth is too great. This reduces flexibility while increasing the cell cost per BBU.

Thermal considerations are discussed below. During discharging, the temperature of the surface of the battery cell is determined by the battery cell layout, heat dissipation and cooling conditions. For BBU applications, cooling is minimal when the cells are discharged at high power. The determining factors are therefore the cell layout and the corresponding heat dissipation. Generally, the primary heat removal is I²R, wherein I is the discharge current and R is the equivalent internal resistance. In this case, increasing the number of cells connected in parallel will reduce the discharge current, and thus significantly reduce heat dissipation.

Cost considerations are discussed below. For a given output power and standby time, the total energy requirement is determined. Thus, for all possible cell choices, the energy requirements dictate the number of cells required. In other words, for a given number of cells, the number of BBU modules required to form a BBS is a compromise between redundancy and hardware cost. For example, for an N +1 configuration (i.e., +1 redundancy), a 36kW rack would require 8+1 BBUs and 672+84 cells with a 4.5kW/BBU and 6P 14S layout. With a 3kW/BBU and 4P 14S layout, the same rack would require 12+1 BBUs and 672+56 cells. This resulted in 4 BBUs more and 28 cells less. In this case, the cost of the 8+1 configuration is much lower.

FIG. 9 is a flow diagram of a design logic method for designing embodiments of BBU modules and BBSs. First, in act 902, the desired power and stored energy should be determined. The stored energy and the released energy are the product of the desired power and the standby time (which may optionally be adjusted according to efficiency).

The next action 904 is then to set the boundary conditions accordingly. The minimum required energy is determined by the desired power and energy and takes into account the degradation margin. Then, based on the power and energy margins, the maximum achievable power with certain cells may be determined. The maximum achievable power with the various parallels may then be determined.

Next, act 906, is to determine a feasible solution with the specified number of parallel battery cells, the specified number of BBUs, and the form factor based on the particular rack(s) and allowed space.

Next, act 908 is to select a final design based on thermal performance, fault redundancy and degradation margin, and associated cost to optimize a feasible solution. Act 910 is a final selection.

The battery cell package has battery cells to form a pack, which may be further connected to other components. Alternatively, the cell pack may be provided as a stand-alone battery pack containing only battery cells. Thus, without the other components, the length/depth would be only 418.50 millimeters. In one embodiment, there are a total of 84 standard 18650 cells. Six cells were connected in parallel as 6P groups, and 14 groups were connected in series. From the top view of fig. 6, there are two sides. Each side consists of 7 6P groups, which are electrically interconnected in series. As shown in the embodiment of fig. 2, each cell has a constant space between each other. The minimum distance between cells is 1.5 mm edge to edge. The maximum distance D between the battery cell and the top and the bottom of the metal plate of the BBU is 1.5 mm, the distance A between the battery cell and the side part of the BBU is kept to be minimum and not more than 2 mm, and the insulating layer is not included. Two different layouts are proposed as shown in figures 3 and 4. The battery core can be vertically arranged from the top layer to the bottom layer, and also can be staggered from the center to the center by 30 to 45 degrees relative to the bottom layer. These layouts will provide enough room for cooling during high power discharge to protect the cells and extend their life. The housing for the electrical core, for example a cover for an electrical core package, may have holes for ventilation and air cooling. In one embodiment, the cell pack has a length/depth of 418.50 millimeters, excluding the necessary insulation.

Temperature comparison simulations show the thermal behavior of layout 2 at steady state. The design was 60 degrees celsius lower than the reference design, with a 36% increase in power, which was obtained by comparing (a) the proposed design of 4.5kW and (b) the reference design of 3.3 kW.

The electrical parameters are explained as follows. In the case of six standard 18650 cells in parallel, based on experimental results of an equivalent 54W single cell discharge, one embodiment of BBU was optimized for 4.5kW constant output power with an average current per cell of 16.60A for optimal performance. The corresponding energy of 4.5kW is about 0.4kWh per unit. Given the selection of a particular cell, it can provide up to 40.5kW of power in more than 5 minutes with 9 cells stacked together. The energy provided varies between different output powers determined from the characteristics of the selected 18650 cells. It is generally higher at lower output powers. However, if a 30A rated cell is selected under extreme conditions, it can provide a maximum current of up to 180A, which may produce 8kW of peak power in a short time.

The BBUs and cell packs described herein may be applied to facility-level, rack-rank, rack-level, or server-level battery units. It can also be a stand-alone cell pack without other components (including BMS, fan and other circuitry). BBUs can be extended to any number of parallel units to provide significantly higher or lower total output power. It can be assembled in standard rack units, open rack units and ODCC/Baidu rack units, making it a universal standard.

Fig. 10 is a block diagram illustrating an example of an electronics rack, according to one embodiment. The electronics rack 900 may include one or more server slots to receive one or more servers, respectively. Each server includes one or more Information Technology (IT) components (e.g., processors, memory, storage, network interfaces). According to one embodiment, the electronics rack 900 includes, but is not limited to, a CDU 901, a Rack Management Unit (RMU)902 (optional), a Power Supply Unit (PSU)950, a BBU shelf 951 (which may include one or more BBU modules), and one or more pieces of information technology equipment (or IT equipment) 903A-903D (which may be any type of IT equipment, such as a server blade). IT devices 903 may be inserted into the array of server slots from the front 904 or back 905 ends of the electronics rack 900, respectively. The PSU 950 and/or BBU rack 951 may be inserted into any server slot 903 within the electronics rack 900. In one embodiment, one or more BBUs may be inserted into any of the server slots 903 within the electronics rack 900.

Note that although only four IT devices 903A-903D are shown here, more or fewer IT devices may be maintained within the electronics rack 900. Also note that the particular locations of the CDU 901, RMU 902, PSU 950, BBU rack 951, and IT equipment 903 are shown for illustration purposes only; other arrangements or configurations of the CDU 901, RMU 902, BBU951, and pieces of IT equipment 903 may also be implemented. Note that the electronics rack 900 may be open to the environment or partially housed by the rack receptacle, so long as the cooling fan is capable of generating an airflow from the front end to the rear end.

Further, a fan module can be associated with each piece of IT equipment 903 and BBU 951. In this embodiment, fan modules 931A-931E (collectively referred to as fan modules 931) are associated with a plurality of IT devices 903A-903D, respectively. Each of the fan modules 931 includes one or more cooling fans. A fan module 931 can be mounted at the rear end of the IT equipment 903 and/or the BBU951 to generate an airflow that flows from the front end 904, travels through the air space of the IT equipment 903, and exists at the rear end 905 of the electronics rack 900. In one embodiment, each of the fan modules can be mounted at a rear end of a plurality of pieces of IT equipment 903 and one or more BBUs 951. In another embodiment, one or more of the fan modules may be located on the front end 904 of the rack 900. Such front-end fans may be configured to push air into pieces of IT equipment 903 and/or BBU 951.

In one embodiment, the CDU 901 primarily includes a heat exchanger 911, a liquid pump 912, and a pump controller (not shown), as well as some other components (e.g., a reservoir, a power supply, monitoring sensors, etc.). The heat exchanger 911 may be a liquid-to-liquid heat exchanger. The heat exchanger 911 includes a first circuit having an inlet port and an outlet port with a first pair of fluid connectors coupled to external fluid return/supply lines 932 and 933 to form a primary circuit. Connectors coupled to external liquid return/supply lines 932-933 may be provided or mounted on rear ends 905 of electronics rack 900. Liquid return/supply lines 932-933 are coupled to a set of indoor manifolds, which are coupled to an external heat removal system or external cooling circuit. In addition, the heat exchanger 911 also includes a second loop having two ports with a second pair of liquid connectors coupled to a liquid manifold 925 to form a secondary loop, which may include a supply manifold that supplies cooling liquid to the pieces of IT equipment 903 and a return manifold that returns warmer liquid to the CDU 901. Note that CDU 901 can be any type of commercially available or custom CDU. Accordingly, details of the CDU 901 will not be described here.

Each of the plurality of IT devices 903 may include one or more IT components (e.g., a central processing unit or CPU, a Graphics Processing Unit (GPU), memory, and/or storage). Each IT component may perform data processing tasks, where the IT components may include software that is installed in a storage device, loaded into memory, and executed by one or more processors to perform the data processing tasks. At least some of these IT components may be attached to the bottom of any of the cooling devices as described herein. The IT device 903 may include a host server (referred to as a host node) coupled to one or more compute servers (also referred to as compute nodes, e.g., CPU servers and GPU servers). A host server (having one or more CPUs) typically interfaces with a client over a network (e.g., the internet) to receive requests for specific services, such as storage services (e.g., cloud-based storage services, such as backup and/or restore), execute applications to implement specific operations (e.g., image processing, deep data learning algorithms or modeling, etc., as part of a software as a service or SaaS platform). In response to the request, the host server allocates tasks to one or more performance compute nodes or compute servers (having one or more GPUs) managed by the host server. The performance computation server performs the actual task, which may generate heat during operation.

In one embodiment, the BBU shelf 951 is configured to provide backup power (e.g., draw battery energy from one or more battery modules housed therein) to a rack (e.g., one or more pieces of IT equipment 903) when the rack is not drawing power from a primary power source, such as during a power outage. In one aspect, the BBU shelf 951 can include one or more of the BBU modules as described herein.

Electronics rack 900 also includes an optional RMU 902 configured to provide and manage power supplied to server 903, fan module 931, and CDU 901. In some of these applications, the optimization module 921 and the RMC 922 may communicate with a controller. The RMU 902 may be coupled to the PSU 950 to manage power consumption of the PSU. PSU 950 may include the necessary circuitry (e.g., Alternating Current (AC) to Direct Current (DC) or DC to DC power converters, backup batteries, transformers or regulators, etc.) for providing power to the remaining components of electronics rack 900.

In one embodiment, the RMU 902 includes an optimization module 921 and a chassis management controller (RMC) 922. The RMC 922 may include monitors to monitor the operational status of various components within the electronics rack 900, such as the compute nodes 903, CDU 901, and fan module 931. In particular, the monitor receives operational data from various sensors that are representative of the operating environment of the electronics rack 900. For example, the monitor may receive operational data indicative of the temperature of the processor, the coolant, and the airflow, which may be captured and collected by various temperature sensors. The monitor may also receive data indicative of the fan power and pump power generated by the fan module 931 and the liquid pump 912, which may be proportional to their respective speeds. These operational data are referred to as real-time operational data. In one embodiment, the RMC 922 may monitor the power consumption of various components of the chassis. For example, the RMC 922 may monitor the battery energy provided by the BBU951 while the BBU is operational (e.g., providing backup battery power). For example, RMC 922 may obtain current data from the current sensor that is representative of the current discharge of the BBU. Note that the monitor may be implemented as a separate module in the RMU 902.

Based on the operational data, the optimization module 921 performs optimization using a predetermined optimization function or optimization model to derive a set of optimal fan speeds for the fan module 931 and an optimal pump speed for the liquid pump 912 such that the total power consumption of the liquid pump 912 and the fan module 931 is minimized while the operational data associated with the liquid pump 912 and the cooling fan of the fan module 931 are within their respective design specifications. Although illustrated as having only one pump, the CDU may include two or more pumps, as described herein. For example, the liquid pump 912 can facilitate circulation of coolant between the heat exchanger and the BBU951 and/or the one or more pieces of IT equipment (e.g., the hot-side pump 14), while the CDU can include another pump (e.g., the cold-side pump 24) to facilitate circulation of coolant between the heat exchanger and an external heat removal system. Accordingly, the optimization module 921 may perform one or more operations of a thermal management and power optimization algorithm that optimizes the energy cost of powering the liquid pump within given constraints, as described herein. In one embodiment, once the optimal pump speed and optimal fan speed have been determined, the RMC 922 configures the cooling fan(s) of the liquid pump and/or fan module 931 based on the optimal pump speed and fan speed.

For example, based on the optimal pump speed, the RMC 922 communicates with the pump controller of the CDU 901 to control the speed of the liquid pump 912, which in turn controls the liquid flow rate of the cooling liquid supplied to the liquid manifold 925 for distribution to at least some of the server blades 903. Thus, the operating conditions and the corresponding cooling device performance are adjusted. Similarly, based on the optimal fan speed, the RMC 922 communicates with each of the fan modules 931 to control the speed of each cooling fan of the fan modules 931, which in turn controls the airflow rate of the fan modules 931. Note that each of the fan modules 931 may be individually controlled at its particular optimal fan speed, and that different fan modules and/or different cooling fans within the same fan module may have different optimal fan speeds.

Note that some or all of the IT equipment 903 (e.g., 903A, 903B, 903C, and/or 903D) may be attached to any of the above-described cooling devices via air cooling using a heat spreader or via liquid cooling using a cold plate. One server may utilize air cooling while another server may utilize liquid cooling. Alternatively, one IT component of a server may utilize air cooling while another IT component of the same server may utilize liquid cooling. Furthermore, switches are not shown here, which may be air-cooled or liquid-cooled.

In the foregoing specification, embodiments of the disclosure have been described with reference to specific exemplary embodiments thereof. It will be evident that various modifications may be made thereto without departing from the broader spirit and scope of the disclosure as set forth in the claims. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.

While certain aspects have been described and shown in the accompanying drawings, it is to be understood that such aspects are merely illustrative of and not restrictive on the broad disclosure, and that this disclosure not be limited to the specific constructions and arrangements shown and described, since various other modifications may occur to those ordinarily skilled in the art. The description is thus to be regarded as illustrative instead of limiting.

In some aspects, the disclosure may include language, e.g., "at least one of [ element a ] and [ element B ]. Such language may refer to one or more of these elements. For example, "at least one of a and B" may refer to "a", "B", or "a and B". Specifically, "at least one of a and B" may mean "at least one of a and B", or "at least one of a or B". In some aspects, the disclosure may include language, e.g., "[ element a ], [ element B ], and/or [ element C ]". Such language may refer to any one of, or any combination of, the elements. For example, "A, B and/or C" may refer to "a", "B", "C", "a and B", "a and C", "B and C", or "A, B and C".