Modular, scalable battery energy storage system

Abstract

A modular battery energy storage system comprising a frame having a wiring harness and a plurality of battery module support assemblies. A plurality of storage modules for storing energy are adapted to slidably engage with the frame along the battery module support assemblies and electrically connect to the wiring harness via a wiring harness connector. A wiring box is electrically connected to the wiring harness and used for coupling AC power to / from the wiring harness.

Description

MODULAR, SCALABLE BATTERY ENERGY STORAGE SYSTEMBACKGROUNDField

[0001] Embodiments of the present invention generally relate to energy storage systems and, in particular, to a modular, scalable battery energy storage system.Description of the Related Art

[0002] Energy storage systems for storing electrical energy have found widespread use in renewable energy systems. To smooth the availability of energy from distributed energy resources (e.g., solar panels, wind turbines, etc.), energy storage systems store electrical energy when excess energy is generated by the distributed resources and supply energy when the resources cannot supply energy (e.g., at night, light wind, etc.). In addition, energy storage systems may store energy supplied by a power grid to either source power when power is unavailable from distributed sources or the power grid, or source power to supplement the grid power during periods of peak demand.

[0003] One form of energy storage system uses batteries to store electrical energy. A battery energy storage system (BESS) typically comprises very large, heavy battery modules that are rack mounted. Installation of a BESS is difficult and time-consuming. Because of the weight and size of a BESS battery module, multiple installers are needed to position, mount and wire the system. Additionally, fixed powerenergy (P:E) ratios of BESS products result in suboptimum installations as installers must choose to meet either the power or the energy needs of the customer when the needed P:E does not match the BESS product P:E, where energy relates to the storage capacity of the BESS and power relates to the amount of energy the BESS can deliver over a period of time.

[0004] In an effort to limit BESS weight, some BESSs are designed as vertically stackable modules such that each module can be carried by a single installer. After stacking the modules, an installer may then wire the modules to one another tocomplete the BESS. These modular systems are very complex and time consuming to install and wire.

[0005] Therefore, there is a need for modular, scalable battery energy storage system that is easy to install.SUMMARY

[0006] A modular, scalable battery energy storage system is provided substantially as shown in and / or described in connection with at least one of the figures, as set forth more completely in the claims.

[0007] Various features and advantages of the present disclosure may be appreciated from a review of the following detailed description of the present disclosure, along with the accompanying figures in which like reference numerals refer to like parts throughout.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] So that the manner in which the various features of the present invention can be understood in detail, a particular description of the invention, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.

[0009] FIG. 1 depicts a perspective view of a battery energy storage system in accordance with at least one embodiment of the invention;

[0010] FIGs. 2 depicts a perspective, exploded view of the battery energy storage system of FIG. 1 in accordance with at least one embodiment of the invention; and

[0011] FIG. 3 depicts a perspective, close up view of a module retainer and module support assembly in accordance with at least one embodiment of the invention.DETAILED DESCRIPTION

[0012] Embodiments of the present invention comprise a modular, scalable battery energy storage system. The system comprises a mounting frame that may be attached to a wall or other supporting surface and a plurality of storage modules attached to and supported by the frame. Each module comprises a modular battery pack and at least one modular power conditioning unit (PCU). The modules are arranged vertically within the frame. Each module slides into the frame along module support assemblies and are retained within the frame. Each module plugs into a prewired, frame mounted wiring harness. A wiring box is positioned on top of the frame and plugs into the wiring harness. The facility (home or business) wiring (i.e., a load center) is then coupled to the wiring box. By using the modular system described in detail below, the BESS installation may be accomplished quickly and by a single installer. The BESS is scalable to fulfill the needs of any facility by increasing or decreasing the number of modules within a frame and / or by adding one or more additional frames and additional modules to the system.

[0013] FIG. 1 depicts a perspective view of a battery energy storage system 100 in accordance with at least one embodiment of the invention. The system 100 comprises mounting frame 102, a wiring box 104 and a plurality of storage modules 106-1 , 106-2, 106-3, 106-4 (collectively referred to as modules 106). Although four modules 106 are shown, the frame 102 may be manufactured in taller or shorter sizes to accommodate any number of modules. In other embodiments, the frame may be manufactured in a wider version to accommodate modules arranged vertically and adjacent to one another.

[0014] Each module 106 comprises a battery pack 108 and at least one power conditioning unit (PCU) 110. In the depicted embodiment, two PCUs 110A and 1 10B are shown coupled to each battery pack 108. Each battery pack 108 (only on is visible in module 106-4) comprises a plurality of battery cells (not visible in this view). The number of cells may vary depending on the storage capacity of the battery pack. However, a typical battery pack comprises about eight cells electrically connected inseries. To enable a single installer to be able to install the BESS 100, the storage modules 106 should weigh about 25kg or less.

[0015] The PCUs 1 10 are bidirectional power converters that, when operated in a discharge mode, convert DC power from the battery pack 108 into AC power (e.g., 120V to 480V one, two or three phase AC power). Additionally, when operating in a charge mode, the PCUs 110 convert supplied AC power to DC power to charge the battery pack 108. Each PCU 110 has a maximum power rating. In one embodiment, each PCU has a power rating of about 650W.

[0016] The modules 106 comprises a pair of module support rails 112 (one rail 112 on each side of the module 106) that is adapted to slide upon and be supported by a complimentary frame rail 114 located on the side of the frame 102. The combination of a module support rail 112 and a frame rail 114 form a module support assembly. Once positioned in the frame 102, the modules 106 are bolted to the frame using a module retainer. The module support assembly and module retainer are described in detail with respect to FIG. 3 below.

[0017] As each module 106 is slid into the frame, a plug on the rear of the module 106 electrically connects to a complementary plug in a wiring harness on the back of the frame 102, as describe with respect to FIG. 2 below. The wiring box 104 is located on the top of the frame 102 and electrically connects to the wiring harness. The wiring box 104 is designed to couple the BESS 100 to a load center such that the stored energy may be used to power loads in a facility.

[0018] FIG. 2 depicts a perspective, exploded view of the BESS 100 of FIG. 1 in accordance with at least one embodiment of the invention. As described above, the BESS 100 comprises a frame 102, a wiring box 104 and at least one storage module 106. The frame 102 comprises a pair of side walls 200A and 200B that extend at substantially right angles from a rear wall 202. The side walls 200A and 200B comprise frame rails 114 that are adapted to interact with module support rails 112 to support the modules 106 within the frame 102. A plurality of stiffening brackets 204 (e.g., four are depicted) are mounted to the rear and sidewalls 200A, 200B and 202to stiffen the frame. The brackets 204 are mounted periodically and spaced to be located between the battery modules 106 along the vertical height of the frame 102. The frame 102 supports a wiring harness 206 that has a connector 208 aligned with each module 106 to provide a communications connection and a power connection. In one embodiment, communications are provided via a controller area network (CAN) bus. In other embodiments, communications are provided by a power line communications (PLC) bus, i.e., the power connection carries communications signals. In further embodiments, other wired communications protocols may be used including, but not limited to, universal serial bus (USB), universal asynchronous receiver / transmitter (UART), serial peripheral interface (SPI), and the like.

[0019] Each module 106 comprises a connector 210 that is complementary to the connector 208 to create a module power and communications connection. As such, the AC power flows to / from the modules 106 via the wiring harness 206. The communications connection couples each module 106 to a battery management unit (BMU) which is typically located remotely from the BESS 100. In some embodiments, the BMU is collocated with the BESS and may be located in the BESS modules 106 or wiring box 104. The wiring harness 208 may include wiring for one, two and / or three phase configurations for the BESS 100. For example, the wiring harness may be wired to accommodate one or more of, but are not limited to, US 240V split phase, EU 230V single phase, US 208 / 120V 3 phase, US 480 / 277 V 3 phase, and / or US 208 / 120V two phase.

[0020] The modules 106 comprise an open topped box 212, a lid 214 and a battery pack 216. The battery pack 216 resides inside the box 212. The battery pack 216 comprises a plurality of battery cells (not specifically shown) and various circuitry (not shown) for monitoring at least one battery pack parameter including, but not limited to, state of charge (SOC) of the cells, the temperature of the cells, voltage levels, current flow and the like. The parameter(s) are communicated through the communication connection (e.g., CAN, PLC, etc.) to the BMU. The modules 106 are designed to produce 3 phase AC power such that, in one embodiment, the connector 210 comprises three AC power pins (e.g., three phase) and four communications pins (e.g., CAN bus). The wiring harness may vary from application to application of theBESS such that the three phase AC of the module 106 is matched to the desired output (e.g., US 240V split phase, EU 230V single phase, US 208 / 120V 3 phase, US 480 / 277 V 3 phase, and / or US 208 / 120V two phase).

[0021] The at least one PCU 110 is electrically connected to the battery pack 218 and the wiring harness 208 via mating connectors 220A, 220B, 222A, 222B. Connectors 220A, 222A carry AC power and communications signals and connectors 220B and 222B couple DC power between the battery pack and the PCU circuitry. The module 106 comprises wiring to couple the AC power and communications signals from connector 220A to the wiring harness connector 210. Each PCU 1 10 is electrically connected by aligning the mating connectors and pushing the PCU 1 10 toward the box 212 and then using fasteners 224 (e.g., bolts or screws) to retain the PCU 110 in position. In this manner, the front mounted PCUs may be quickly and easily disconnected and replaced when a PCU fails.

[0022] In one embodiment, the wiring box 104 comprises an open box shaped housing 226 and a lid 228. In an alternative embodiment, the wiring box 104 has an open box shaped housing with the front being the opening for access to the wiring box 104. A coupler 230 is coupled to a plug 232 at the top of the wiring harness 208. Facility wiring from, for example, a load center connective wires, are coupled to the coupler 230 to couple communications as well as AC power to the load center and BMU, i.e., the wiring box becomes an interface to the facility wiring.

[0023] FIG. 3 depicts a perspective, close up view of a module retainer 300 and module support assembly 302 in accordance with at least one embodiment of the invention. In one embodiment, the module retainer 300 comprises a flange 304 formed at the edge of the module 106. The flange 304 contains a hole 308. Behind the flange 304, a plate 306 containing a threaded hole (behind and aligned with hole 308) is attached to the frame 102. A bolt or screw (not shown) threaded through the hole 308 may be used to retain the flange 304 against the plate 306 and, consequently, retain the module 106 in the frame 102. The foregoing is an exemplary embodiment of a module retainer. Other forms of retainers may be used to affix the modules to theframe. Such retainers may include, but are not limited to, clips, clamps, locks, and the like.

[0024] Here multiple examples have been given to illustrate various features and are not intended to be so limiting. Any one or more of the features may not be limited to the particular examples presented herein, regardless of any order, combination, or connections described. In fact, it should be understood that any combination of the features and / or elements described by way of example above are contemplated, including any variation or modification which is not enumerated, but capable of achieving the same. Unless otherwise stated, any one or more of the features may be combined in any order.

[0025] As above, figures are presented herein for illustrative purposes and are not meant to impose any structural limitations, unless otherwise specified. Various modifications to any of the structures shown in the figures are contemplated to be within the scope of the invention presented herein. The invention is not intended to be limited to any scope of claim language.

[0026] Where conditional language is used, including, but not limited to, “can,” “could,” “may” or “might,” it should be understood that the associated features or elements are not required. As such, where conditional language is used, the elements and / or features should be understood as being optionally present in at least some examples, and not necessarily conditioned upon anything, unless otherwise specified.

[0027] Where lists are enumerated in the alternative or conjunctive (e.g., one or more of A, B, and / or C), unless stated otherwise, it is understood to include one or more of each element, including any one or more combinations of any number of the enumerated elements (e.g. A, AB, AC, ABC, ABB, etc.). When “and / or” is used, it should be understood that the elements may be joined in the alternative or conjunctive.

[0028] While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.

Claims

Claims:1 . A modular battery energy storage system comprising: a frame comprising a wiring harness and a plurality of battery module support assemblies; a plurality of storage modules for storing energy that are adapted to slidably engage with the frame along the battery module support assemblies and electrically connect to the wiring harness via a wiring harness connector; a wiring box, electrically connected to the wiring harness, for coupling AC power to / from the wiring harness.

2. The modular battery energy storage system of claim 1 wherein the wiring harness carries communications signals between the wiring box and the plurality of storage modules.

3. The modular battery energy storage system of claim 1 wherein each storage module in the plurality of storage modules comprises a battery pack and at least one power conditioning unit.

4. The modular battery energy storage system of claim 3 wherein the at least one power conditioning unit is a bidirectional power converter for charging and discharging the battery pack.

5. The modular battery energy storage system of claim 1 wherein each storage module in the plurality of storage modules weighs about 25 kg or less.

6. The modular battery energy storage system of claim 1 wherein the battery module support assemblies comprise a support rail located on each side of each storage module, where each support rail slidably interacts with a complementary frame rail located on a side wall of the frame.

7. The modular battery energy storage system of claim 1 wherein the frame comprises two side walls and a rear wall, where the side walls extend from the rear wall at substantially a right angle.

8. The modular battery energy storage system of claim 7 wherein the wiring harness is attached to the rear wall.9 The modular battery energy storage system of claim 7 further comprising a plurality of stiffening brackets attached to the side walls and the rear wall.

10. The modular battery energy storage system of claim 1 wherein the wiring box is mounted to the top of the frame.

11. The modular battery energy storage system of claim 1 further comprising a module retainer to couple each storage module to the frame.

12. The modular battery energy storage system of claim 1 wherein, when the storage module is slidably installed into the frame, a connector on the rear of the storage module mates with a complimentary connector of the wiring harness.

13. A method of assembling a modular battery energy storage system comprising:(a) placing a pair of storage module support rails that are attached to a storage module onto a pair of frame rails that are attached to two sidewalls of a frame;(b) sliding the pair of storage module support rails along the pair of frame rails until the storage module is inserted into the frame; and(c) automatically connecting a storage module connector to a wiring harness connector when the storage module is inserted into the frame.

14. The method of assembling a modular battery energy storage system of claim 13 further comprising using a module retainer to retain the storage module in the frame.

15. The method of assembling a modular battery energy storage system of claim 13 further comprising repeating (a), (b), and (c) to insert a plurality of storage modules into the frame.

16. A modular battery energy storage system comprising: a frame comprising a wiring harness and a plurality of battery module support assemblies, where the frame comprises two side walls and a rear wall; a plurality of storage modules for storing energy that are adapted to slidably engage with the frame along the battery module support assemblies and electrically connect to the wiring harness via a wiring harness connector; a wiring box, electrically connected to the wiring harness, for coupling AC power and communications signals to / from the wiring harness, where the wiring box is mounted to the top of the frame and the wiring harness is attached to the rear wall of the frame.

17. The modular battery energy storage system of claim 1 wherein each storage module in the plurality of storage modules comprises a battery pack and at least one power conditioning unit.

18. The modular battery energy storage system of claim 17 wherein the at least one power conditioning unit is a bidirectional power converter for charging and discharging the battery pack.

19. The modular battery energy storage system of claim 16 wherein each storage module in the plurality of storage modules weighs about 25 kg or less.

20. The modular battery energy storage system of claim 16 wherein the battery module support assemblies comprise a support rail located on each side of eachstorage module, where each support rail slidably interacts with a complementary frame rail located on a side wall of the frame.

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