Battery energy storage system with ac and DC backup functionality

Abstract

A battery energy storage system is provided that includes at least one inverter that provides charging functionality to at least two batteries, wherein a first battery provides DC backup power and a second battery provides AC grid tie functionality. The battery that provides DC backup power may be associated with a diode that prevents current flow from a DC bus back to the battery that provides DC backup power. The inverter may be connected to a load using a smart breaker, and the load may be a power system that includes a rectifier. The battery energy storage system may be deployed in various settings, including telecommunications sites.

Description

[0001] Battery Energy Storage System with AC and DC Backup Functionality

[0002] Cross-Reference to Related Application

[0003] The present application claims priority benefit to a US provisional patent application entitled "Battery Energy Storage System with AC and DC Backup Functionality," filed on July 27, 2023, and assigned Serial No. 63 / 529,285. The entire content of the foregoing provisional application is incorporated herein by reference.

[0004] Technical Field

[0005] A battery energy storage system is provided that includes at least one inverter that provides charging functionality to at least two batteries, wherein a first battery provides DC backup power and a second battery provides AC grid tie functionality.

[0006] Background

[0007] With the rapid expansion of wireless communication systems worldwide, and the increasing socioeconomic benefits of mobile phone technology, the need for dependable and economical backup power is critical. Electric grid loss throughout the year, whether from severe weather, natural disasters, or limited grid capacity, is an ongoing challenge for network operators.

[0008] Traditional telecom backup power solutions include lead-acid batteries for short duration backup and diesel and propane generators for longer duration backup. Diesel and propane generators are typically capable of longer duration backup power. However, generators can be unreliable, maintenance intensive, and emit high levels of pollution and greenhouse gases into the atmosphere.

[0009] Traditional power systems having backup functionalities for applications such as found in Telecom power systems, data centers, and other industrial applications requiring a battery back-up system (one of which can be a so-called uninterrupted power system, UPS), typically use rectifier technology that rectifies an AC connection to a DC bus connection that feeds a number of DC loads. The DC BUS, represented in Figure X 48VDC BUS(22), then connects multiple loads, commonly through a series of breakers all powered by the rectifier(s). The DC BUS is also connected to a backup battery bank, which immediately backs up the DC loads, should a power grid outage occur. The battery bank consists of a number of lead acid or Li-ion batteries, which back up the DC loads until a generator can be started. Since the batteries are directly connected to the DC Bus, the battery backup power is immediately available when the grid fails, and an AC power disruption occurs. This means that equipment, such as communication systems, will be continuously connected to a power source, as there is no switchgear that requires reaction time to interconnect between the rectifier and the battery power sources, the transition is immediate. This immediacy is important so that communication is not lost.

[0010] For firefighters battling a raging inferno, presenting imminent danger to both residents and the emergency responders, a communications infrastructure must operate without compromise. Similarly, a paramedic assisting victims of an accident or assault needs to have reliable communication between the scene of the accident and the closest medical facility. In these situations, effective and reliable backup power systems are imperative, and a reliable UPS is needed to maintain system uptime.

[0011] The backup batteries used are typically sized to supply the desired power to the application for a few minutes to, typically, less than an hour, having enough time to start up a diesel or natural gas generator. Sometimes a DC generator is used (especially when no utility grid is available and no AC power is required, such as for remote telecommunication sites) and sometimes an AC generator is used (when a regular AC utility grid is present). When an AC generator is present, non-DC loads at a site, such as lights and other AC functions, can be powered, while a DC generator would power only the DC loads and are therefore only used in remote instances where no general power grid is available. Companies that sell these traditional system or components for power systems having battery back-up includes American Power Conversion (APC), Schneider Electric, General Electric, Eaton, Huawei Technologies Co., Delta, Emerson and others.

[0012] With the onset of the smart grid using a number of internet connected components for remote monitoring and steering, such as smart power meters for measuring bidirectional energy delivery to an address, new battery systems are coming on the market that have grid tie functionalities. These systems can deliver charge / discharge functionalities that are controlled in a number of ways. Examples include timed controls to an electric tariff (referred to as Time-of-Use arbitrage) or a demand response discharge from an external signal originating from a utility or an aggregator. These battery systems are typically based on bi-directional inverters that, on one hand have the capability of converting AC power to DC power (similar to a rectifier) and subsequently charge a battery or power DC loads, but on the other hand have the added functionality of inverting the DC power from the battery to AC power, all in one system.

[0013] The bi-directional inverters can be electrically configured to be grid forming, meaning they can create their own grid, which is important for creating an isolated micro grid. They can also be grid following, meaning the inverter can adjust its AC functionality to follow a pre-existing utility grid interconnection in terms of the electric grid's voltage levels and phases. These newer battery systems can further be AC or DC connected to a solar power system or other renewable energy source such as wind, hydropower or a fuel cell. The battery systems can also be further connected to a traditional fossil fuel generator, which may use natural gas, propane, diesel, or gasoline as energy source, and used as additional backup energy.

[0014] Inverters that have grid forming capability can be used as a backup power system for AC applications, by powering the rectifier through its AC out connection powered by the battery DC storage, where the AC out connection is the grid forming connection from the inverter. Many such types of bidirectional inverter technology exist. Examples are the XW Pro by Schneider or the Sol- Ark by Sol-Ark for smaller power systems. Other larger power systems (up to several megawatts) are also in use that have the same functionalities, often employing technology made by Power Electronics or Chint Power Systems (the CPS1500). These systems convert DC power from as low as 48VDC up to 1500VDC and higher. The output can be single phase 120VAC, split-phase 240VAC, or 3- phase 480VAC feeds. Other voltage levels exist at various phases depending on the region, with the inverter technology being similar in nature but adopted to the desired grid type and voltage, along with the desired battery power and DC voltage. Inverters that can connect both solar power and battery power and also perform grid tie functions are sometimes referred to as hybrid inverters. With newer types of battery energy storage systems (BESS), battery storage can therefore replace polluting fossil fuel generators. If a solar or wind system is also connected, the inverter / battery systems can be recharged on a regular basis from renewable energy thereby making the power delivered less carbon intensive. Other renewable energy sources, such as fuel cells, are additionally possible energy sources for the microgrid in conjunction with the new battery systems.

[0015] The size of the battery bank and the size of the renewable generation can be designed for the desired backup time of any given application. For Telecom applications, there is sometimes a minimum of 8 hours of backup needed due to the code requirements and other regulations, and in other cases and applications, multiple days of backup may be required. While the rectifier-based power systems have backup battery power that immediately backs up the DC equipment due to the interconnected batteries connected to the DC Bus, the inverter systems require several milliseconds to switch over when a grid interconnection fails. This gap in time is enough to disrupt communication systems resulting in failures that can shut down the desired functionalities.

[0016] For such a delay to be avoided, UPS systems have to be deployed that continuously deliver DC power to a device in case of grid failure or a permanent battery is connected to the DC bus. The cost of these systems is therefore very high, as many sub-systems need to be used in parallel for a complex system. Besides the high costs, systems are challenging to integrate, and become energy inefficient due to the many steps of energy conversion. Further, the rectifiers have the disadvantage of not being able to deliver the full suite of financial benefits that modern BESS units do.

[0017] Thus, there are multiple benefits that can be achieved through development of advanced energy storage systems. These benefits include improved environmental impact, lowering the carbon footprint of these types of applications, and improved financial metrics that lower electricity costs and allow for participation in revenue generation tied to grid support functions. These benefits motivate the need to create new systems that effectively combine the backup functionalities with the grid tie benefits. New configurations of hardware and software functions are required that enable the functionalities described above, including time-of-use controls, demand response functionalities, demand charge reduction through peak shaving, and load shifting functionalities. These functionalities further require incorporation of solar, wind or other renewable systems. By deploying these systems, the cost of electrical energy will be less as renewable energy can be deployed while reducing the system's carbon footprint.

[0018] Summary

[0019] The presently disclosed Battery Energy Storage System (BESS) advantageously addresses an industry need for seamless, non-interrupted backup power while providing a system that can automatically switch over to grid tie operations, thereby delivering cost lowering features for the electrical utility using metrics such as time of use and demand charge reduction functionalities. Such features are implemented by controlling the charge discharge operations of the disclosed BESS as a function of time or as a result of analyzing the signal from the power meter The disclosed BESS also allows for the ability to generate income (and cost / revenue optimization) through traditional grid tie functions of modern battery energy storage systems. The disclosed system automatically transitions to backup power when a grid shuts down, without the short interruption to shift between the utility grid energy source and the battery back-up energy source that is generally required for an inverter or automatic transfer switch. The disclosed BESS can also operate and be configured so that CO2is optimized. The carbon dioxide (CO2) can be optimized in part through the configuration and methods described in commonly assigned WO2023 / 235593 to Sharma et al., the content of which is hereby incorporated by reference in its entirety.

[0020] In one embodiment, the disclosed BESS can be integrated behind one smart meter and deliver its functionality entirely behind that meter. In another embodiment, the disclosed BESS can be used behind a second smart meter that provides energy services to the first smart meter, wherein each meter can be owned by separate parties. The present BESS further enables a seamless transition to backup functionalities with no power interruption when a grid outage occurs, which is similar to a traditional backup power system. Multiple disclosed BESS can be configured in parallel as further described below. Such parallel configurations can support multiple sets of equipment requiring back-up functionality.

[0021] The disclosed BESS can deliver all of these functionalities at high efficiency and low cost because at least two battery banks have been incorporated within the system in such a way that backup is delivered without power interruption and the implementation of smart breakers. The smart breakers in the BESS use software to allow control of the functionalities described above to be delivered to the application.

[0022] The disclosed BESS limits the number of power transformation devices needed in the circuitry. Without this novel design, a system would otherwise require additional rectifiers to operate and would not have the flexibility and low cost of the disclosed BESS.

[0023] The presently disclosed BESS has two or more electrical outputs in both DC and AC configurations. In this exemplary design, one or more AC-out connections provide the backup power to the AC loads, and one or more DC-out connections provide an immediate backup to connected DC loads. Unique to this design, all the battery modules are connected to a single inverter system for the purpose of charging batteries that have low state of charge. The multiple battery banks may, for periods of time, have the same voltage level or different voltage levels. During simultaneous charging, the multiple battery banks should be kept at about the same voltage levels to avoid a high inrush of current from one battery bank to the other battery bank.

[0024] The disclosed BESS can be further configured to utilize a DC / DC converter connected to the output of the DC-out circuit, which can adjust the voltage levels to the DC loads connected. This will allow high voltage levels to the loads, which minimizes the currents for power required to operate the equipment. This, in turn, allows for use of lower gauge cabling or enables longer transmission of power without reducing the voltage level below the specification of the operational voltage for a DC device. Also, when different voltage levels are used for the two battery banks in the disclosed BESS, a DC / DC converter can be used to convert the voltage to a specified voltage range suitable to charge the battery for the DC-out connection.

[0025] The disclosed BESS also has one or more smart breakers that enable and can automatically allow rectifiers and other AC loads to connect, which replaces the function of a fossil fuel electrical generator and delivers cost savings to the power system for a site. In an embodiment, the disclosed BESS is connected to one smart meter and delivers services behind a second smart meter.

[0026] Besides having batteries with different voltage levels, the batteries can also be of different type and have different capacities. For instance, in an embodiment, one of the batteries can be a lithium-ion battery designed for high energy that enables back up for several hours, while a second battery is sized smaller for the DC-out functionality. In this embodiment, the second battery is designed to deliver a short power pulse that is strong enough to connect the AC-out in the case of a grid outage, allowing a seamless delivery of power without disrupting power to a DC bus.

[0027] In yet another embodiment, at least one of the batteries is of "power" type and one of the batteries is of "energy" type, meaning they are designed through the use of suitable electrode formulations to deliver their stored energy through output power during a long duration (several hours) for an energy type, versus a short duration (less than an hour) for a power type. A power battery configured using the disclosed BESS would be suitable for the immediate transfer required at the DC- out connection bridging backup functionality without any power disruption.

[0028] While the battery modules supporting the DC connection are preferably connected to the one inverter system charging the one or more strings of battery modules, the battery modules backing up loads on the DC bus can also be charged by an individual rectifier or battery charger. In such situations, it is preferred that the rectifier / charger is connected to the AC out grid forming connection of the inverter system. The rectifier / charger can alternatively be connected to the AC in the utility grid point, but would then not be backed up by the microgrid as the utility connection to the grid needs to be isolated against the microgrid feed. Without this isolation, the microgrid would feed the generic utility, which is a safety issue for any service work performed.

[0029] The innovative batteries described herein can be deployed under a number of ownership and business models due to the use of smart breakers that connect a customer's loads for backup service or for grid tie services. The grid tie functions may include time of use arbitrage, demand charge reduction, or demand response functionalities that are financially rewarded by either a tariff structure from the electrical utility or the income generated from a demand response function. If a solar or other renewable system having unpredictable energy supply is directly connected to such a system, the time of use functionality can be optimized based on such energy sources.

[0030] Ownership models include a battery purchased by the owner of a site who operates the battery by delivering services to a second user within the general area for which revenue is generated. In yet another model, the battery can be owned by a third party that provides energy services. One such business example is a battery for use at a Telecom site where it is common for a site owner to lease its real estate and provide an infrastructure that a carrier customer utilizes for its communications equipment. Companies pursuing this line of business include companies that own and operate wireless and broadcast communications infrastructures. Examples of such companies include American Tower Corporation, Crown Castle, Diamond Communications, SBS Communications and others. Telecom carriers that utilize such sites by leasing infrastructure and buying various services from the site owner include AT&T, Verizon, T-Mobile, and others. While the disclosed BESS is suitable for Telecom applications, other applications and types of sites can also be considered. These may include data centers, backup for municipalities for society critical services such as communication centers, police and fire departments, and hospital back power needs. All applications that require back up, including those that require DC back up and / or are AC grid tied for financial and / or carbon benefits delivered by a battery system are suitable applications for the innovative system disclosed herein.

[0031] The Energy services provided by the disclosed BESS can be referred to as "Energy as a Service" (EaaS) or "Power as a Service" (PaaS), which are business models where customers pay for an energy service without having to make an up-front investment into and own the capital equipment. In commercial and industrial applications, such as Telecom or other commercial and industrial uses, multiple customers may be collocated at a site wherein each customer can have its own power meter and its own individual equipment. Examples of such applications may be malls, apartment buildings, hospitals, or other commercial buildings, where a number of tenants typically lease space.

[0032] Additional features, functions and benefits of the disclosed systems will be apparent from the detailed description which follows, particularly when considered in conjunction with the figures provided with this application.

[0033] Brief Description of the Figures

[0034] To assist those of skill in the art in practicing the subject matter of the present application, reference is made to the following figures:

[0035] Figure 1 is a diagram of an exemplary BESS configuration according to the present disclosure; and

[0036] Figure 2 is a diagram of an alternative exemplary BESS configuration according to the present disclosure.

[0037] Detailed Description Figure 1 and Figure 2 show electrical one-line diagrams incorporating the main electrical components of a novel battery energy storage system (NBESS) and how the same NBESS is connected to a traditional power system (represented by components 16, 10, 18, and 9), and further interconnecting an AC connected solar power array (represented by components 14 and 15). Of note, many alternative BESS designs may be configured similarly in parallel, e.g., if multiple sets of equipment need to be backed up.

[0038] Referring to Figure 1 and Figure 2, the disclosed BESS has a bidirectional inverter (1), a smart breaker (5) connected to the AC Out and another smart breaker (6) connected on the DC connection ahead of Battery Bank 2 (4), a diode (7) sits before a DC out connection, and a Controls Unit that send signals to the two smart breakers and the inverter. The smart breaker (6) is used for when the Battery Bank 2 (4) would need to be charged.

[0039] In the figures, the disclosed BESS connects to each phase of the utility connection behind a smart meter. The inverter is further connected to at least two battery banks, Battery Bank 1 (2) and Battery Bank 2 (4). Battery Bank (1) consists of a number of battery modules in parallel, which is represented by sixteen lOOAh battery modules having a nominal voltage of 51.2VDC each. Battery Bank 1 is marked with 48VDC in the figures.

[0040] The diode (7), which is typically located in the disclosed BESS just ahead of the DC output, will prevent any charging current from the rectifier RECTI (16) located in a traditional Telecom power system. The diode can be located anywhere between the 48VDC bus (22) from the RECTI (16) and the Battery Bank 2 (4). The smart breaker (5) located ahead of RECTI is controlled by the disclosed BESS control system and can be used support AC power for the traditional power system for telecom (19). By connecting on the AC side of the rectifier, the disclosed BESS can take advantage of benefits through energy arbitrage (time-of-use), power reduction delivering a net demand charge reduction, or a demand response generating income from a utility from such financial incentive programs. With the combination of the smart breaker (5) providing an ability to support the AC connection to the rectifier RECTI (16) and the Battery Bank 2 (4) providing DC power back up through a diode DI, seamless power is delivered to the Critical DC Loads (10) necessary to perform the telecom communications or other mission critical tasks. This dual functionality of AC and DC coordinated backup with ability for traditional BESS functionality makes the disclosed BESS desirable for the telecom industry.

[0041] It should be noted that the Battery Bank (2) can also be connected via a separate rectifier / charger, connected to the main grid connection or the AC Out position and provide the desired backup functionality of non-interrupted power to the 48VDC bus (22). However, this solution comes at an additional cost because of the rectifier, which is not required when the disclosed BESS comprises Battery Bank (2), as shown in Figures 1 and 2.

[0042] Optionally a DC / DC converter can be used to adjust the DC power from the inverter's DC output and enable direct charging to a battery that backs up the DC bus, which allows for the onset of charging when the battery has a significantly different voltage level than the other string of battery modules supporting the AC backup through the inverter.

[0043] For ease of reference, the reference designations in the figures are as follows:

[0044] 1. Bi-directional Inverter

[0045] 2. Battery Bank 1

[0046] 3. Smart circuit breaker (CB4)

[0047] 4. Smart circuit breaker (CB2)

[0048] 5. "Cloud box", a microprocessor or programmable logic controller with remote functionality

[0049] 6. Battery Bank 2

[0050] 7. Diode, DI

[0051] 8. Manual Service Breaker AC

[0052] 9. Lead Acid Battery Bank

[0053] 10. Critical DC loads

[0054] 11. Smart Power Meter (M or Ml)

[0055] 12. Smart Power Meter (M2)

[0056] 13. Critical AC Loads

[0057] 14. Solar Inverter 2

[0058] 15. Solar (PV) panels

[0059] 16. Rectifier

[0060] 17. Manual Service Disconnect (DISC 1)

[0061] 18. Manual Circuit Breaker for Lead Acid Batteries

[0062] 19. Traditional Power System for Telecom Station

[0063] 20. DC EaaS Connection

[0064] 21. Manual Service Breaker DC

[0065] 22. 48VDC bus located While the disclosed BESS can be used for a variety of applications, including but not limited to those referenced above, the disclosed battery systems will be described in the context of a Telecom site having a pre-existing traditional power system consisting of an AC connected rectifier. The disclosed system delivers power to several DC loads (such as communication devices) positioned behind a number of breakers and a back-up battery (typically a bank of four lead acid batteries delivers 48VDC).

[0066] The disclosed system is different from a traditional power system for telecom base stations (19) having a rectifier and a number of DC loads, a backup battery further connecting to those loads (which is charged by the rectifier), and optionally also a fossil fuel generator for additional time of backup during grid outages. Other configurations exist for such traditional power systems, but typically these installations have a battery backup that bridges the power to the telecom station loads (such as transmitters, receivers, multiplexers and other electronic equipment used for the cell tower communications). The rectifier-based power system is typically located in an outdoor cabinet or in a rack located in a nearby shelter.

[0067] The disclosed BESS can interface with a traditional system by providing uninterrupted power to the AC side of the rectifier with only a small disruption (a few milliseconds delay for the case of the inverter on the AC connections), and also continuous backup without delay on the DC connection behind the diode (7) and the Battery Bank 2 (4).

[0068] The batteries of Battery Bank 1 (2) can be used in place of a lead acid battery bank at a 48VDC typical battery bank voltage. An example of such a lOOAh module is the CI48100 developed by Cadenza Innovation, Inc. (Danbury, CT), where sixteen such modules deliver 1600Ah storage capacity. Other similar modules are available in the industry from battery companies such as CATL, EVE, Samsung SDI, LG Chem, and others. It can be understood by those skilled in the art that other inverter battery combinations can be utilized in the disclosed BESS, such as higher DC voltage as high as 500VDC, 1000VDC, or 2000VDC.

[0069] In an embodiment, the disclosed BESS may not utilize diode DI (7), but the diode may be preferred as it prevents the automatic charging from the 48VDC bus (22) connected behind the rectifier RECT 1 (16). If such charging is allowed, the system would still function.

[0070] When a service provider is supporting an equipment owner, as in the case of a telecom carrier and a real estate site owner providing energy services, the diode is particularly beneficial as it allows power and energy support for financial optimization of the site carriers interconnection, while at the same time eliminating the need for the carrier to install backup batteries behind the RECTI. The disclosed BESS provides immediate backup power functionality. The interconnection point from the novel system is marked by the DC EaaS Connection (20), where the EaaS terminology is intended to represent the feature of the energy as a service aspect of the immediate DC backup functionality option.

[0071] Additional components are noted in the Figures and may be necessary for the electrical configuration and service aspects, such as multiple manual service breakers. In some embodiments, certain components may be optional.

[0072] A DC service breaker (21) is located between the traditional telecom power system (19) and the disclosed BESS. An AC service breaker (8) is located between the AC out of the inverter connection and a renewable energy system co-located on the site. The renewable energy system may be a solar system (represented in the figures by a solar inverter (14) and the solar photovoltaic (PV) panels (15)). Another AC manual service breaker DISCI (17) connected to an auxiliary contact that can trip the inverter is used for disconnecting the disclosed BESS when supported circuits need to be deactivated due to safety concerns. Safety concerns may arise during a fire or during maintenance or other electrical work. A standard fossil fuel generator, such as a diesel or natural gas generator, can be connected in addition to (not shown in figures) or in replacement of the solar system. The AC out can also include other critical AC loads, in addition to the RECT 1 rectifier. Examples of other critical AC loads may include lights, water pumps or other site equipment not directly involved with telecommunications but necessary for the site operation. The disclosed BESS allows financial optimization of such AC loads as well for the site. The novel system described herein provides a holistic solution to control both the site operations and the AC and DC backup functionality of the telecom equipment.

[0073] The disclosed BESS that features two or more battery banks on the DC side of the inverter, where one or more of the battery banks are used for the inverter functions only and at least one or more battery banks are used for the immediate DC back up, can optionally be configured with multiple inverters to allow higher power delivery on the AC connections and allow higher power to be received from the battery banks to the inverter system. Such inverter configurations are well known in the industry and referred to as master-slave configurations wherein each phase providing power (typically single phase, split phase or three phase) has a master-slave multi-inverter function. Inverters that provide three phase power from one inverter also exist and can be configured in a master-slave configuration. A person skilled in the art would understand how these inverter options can be configured in context of the novel battery system described herein. Cloud Box (3) is a microprocessor or PLC that can remotely send, monitor, change, and record parameters that may trigger action on several levels. The Cloud Box may control, amongst other components, the inverter (1), the battery banks (2) including the individual battery modules and each individual battery management systems, the smart circuit breakers, and a power meter monitor behind a smart power meter. The Cloud Box can simultaneously be connected to internet cloud software that can deliver demand response actions to and from the disclosed BESS. While the exchange between any external aggregation of the battery from a central location or aggregator / utility appears in the cloud software, the Cloud Box has the ability to carry out action that integrates and optimizes the disclosed BESS at a selected site.

[0074] The BESS described herein can be installed behind one smart power meter M (11) as shown in Figure 1, where the AC out connection from the inverter (1) is connected to a number of critical loads (13) that require AC power and also a solar power system. This configuration is beneficial when a solar system is present in the BESS because the solar inverter (14) needs to detect a power grid to operate. Such solar inverters are well known in the industry and are configured to shut down if a power grid failure occurs. Therefore, when a grid forming inverter is used and when the solar inverter is connected to the DC out, the AC backup function will enable the solar system to operate even when the grid is out. This novel BESS enables a local grid through its inverter in backup mode. This in turn extends the time of the AC backup power, as extra energy from the solar system can be delivered to charge the batteries (or augment the power from the batteries).

[0075] Alternatively, the disclosed BESS can be installed behind a first meter Ml (11) as shown in Figure 2, where the AC out from the inverter is supporting a number of AC critical loads. This configuration includes a traditional power system which has a rectifier RECTI (16) AC connection installed behind a second power meter M2 (12). In this configuration, the regular power supply to the rectifier is delivered from a separately invoiced smart power meter and the disclosed BESS installed behind the first meter can support the system with a second power supply in addition to the traditional rectifying system.

[0076] Although the present disclosure has been provided with reference to exemplary embodiments and / or implementations, the present disclosure is not limited by or to such exemplary embodiments and implementations. Rather, modifications, refinements and enhancements may be made without departing from the spirit or scope of the present disclosure, as will be apparent to a person of ordinary skill in the art based on the disclosure provided herein.

Claims

Claims1. A battery energy storage system, comprising: at least one inverter that provides charging functionality to at least two batteries, wherein at least one battery of the at least two batteries provides DC backup power and at least one battery of the at least two batteries provides AC grid tie functionality.

2. The battery energy storage system of claim 1, wherein the at least one of battery that provides AC grid tie function has higher energy than the at least one battery that provides DC backup power.

3. The battery energy storage system of claim 1, wherein at least one of the batteries is a power battery.

4. The battery energy storage system of claim 1, wherein at least one of the batteries is an energy type battery.

5. The battery energy storage system of claim 1, wherein a regenerative energy source is used to charge the at least one battery that provides DC backup power.

6. The battery energy storage system of claim 5, wherein the regenerative energy source is used to charge all batteries through an AC interconnection to the at least one inverter.

7. The battery energy storage system of claim 5, wherein the regenerative energy source is at least one of solar, wind, fuel cell, or hydro-power.

8. The battery energy storage system of claim 1, wherein the at least one battery that provides DC backup power is associated with a diode that prevents current flow from a DC bus back to the at least one battery that provides DC backup power.

9. The battery energy storage system of claim 1, wherein the at least one inverter is connected to a load using a smart breaker.

10. The battery energy storage system of claim 9, wherein the load is a power system that comprises a rectifier.

11. The battery energy storage system of claim 8, wherein the diode is associated with a DC battery that has a lower energy capacity than the at least one battery that provides DC backup power.

12. The battery energy storage system of claim 1, wherein the at least one battery that provides DC backup power is connected via a smart breaker.

13. The battery energy storage system of claim 12, wherein the at least one battery that provides DC backup power that is connected via a smart breaker is further connected to a DC outlet via a diode.

14. The battery energy storage system of claim 1, wherein the at least two batteries comprise two DC batteries at different voltages through use of a DC / DC converting device.

15. The battery energy storage system of claim 1, wherein the at least one inverter and the at least two batteries are deployed at a telecommunications site.

16. The battery energy storage system of claim 1, wherein the at least one inverter and the at least two batteries provide energy services owned by a first entity and deliver services to a second entity.

17. The battery energy storage system of claim 16, wherein the second entity has electrical services delivered through a power meter that is separate from a power meter of the first entity.

Images