Battery energy storage system

Abstract

The present invention is an energy storage system: comprising a plurality of elongated compartments, each designed to house a string of energy storage cells; each compartment being provided with an accessible opening designed to facilitate the easy setting and removal of the storage cells; these compartments being designed to accommodate two or more storage cells positioned adjacent to each other within their tips; a holding mechanism is also incorporated, which serves to firmly press the strings of cells against each other and hold them, thereby forming a reliable current path; the system incorporates a balancing mechanism; this mechanism includes a balancing system with electrical tabs, these electrical tabs connecting adjacent cells with a mechanism for moving charge in and out of these tabs. This movement of charge facilitates the charging and discharging of the cells, thereby maintaining a balanced voltage across the system.

Description

Technical Field

[0001] The present invention relates to the field of energy storage systems, and in particular focuses on efficient, economic, and practical solutions that can be adapted to a wide range of applications, from residential to grid-scale energy storage.

Background Art

[0002] The increasing urgency to mitigate climate change has driven rapid development in renewable energy technologies. These technologies, such as solar and wind power, offer a promising future using abundant and cost-effective energy with minimal environmental impact. Despite this potential, renewable energy faces significant limitations in its intermittency. These sources generate energy only when the sun is shining or the wind is blowing, not necessarily when energy is needed. To utilize their maximum potential and transition from fossil fuel-based energy systems, efficient and economic energy storage solutions are required.

[0003] Energy storage systems provide a means to match the energy generation from renewable resources to demand. They store surplus energy generated during periods of high generation and low demand and release it back to the power grid when demand exceeds generation. Thus, they offer the possibility to maximize the utilization of renewable energy sources, reduce dependence on fossil fuels, and help significantly reduce greenhouse gas emissions.

[0004] Over the years, many energy storage systems have been developed, ranging from pumped hydroelectric storage to battery technologies such as lead-acid and lithium-ion, as well as new technologies such as solid-state batteries and flow batteries. However, these solutions often come with their own set of challenges. For example, pumped hydroelectric storage, while effective, requires large spaces and specific geographical features and is unsuitable for many applications. On the other hand, battery technologies can be costly, have variable energy densities, and often require complex battery management systems (BMS) to ensure safe and efficient operation. The lifespan and maintenance checks of these systems also pose significant challenges and contribute to high capital costs and electronic waste.

[0005] In addition, the need for efficient energy storage is not limited to the transmission grid scale. Energy storage is also important at smaller scales, such as in residential, commercial, and industrial settings. These applications present their own unique challenges, such as space constraints, their own energy requirements, and a higher need for safety and reliability.

Summary of the Invention

Problems to be Solved by the Invention

[0006] Current solutions often require unique production designs for each application area, making them expensive and difficult to provide. For example, residential solar / battery systems often require a hybrid inverter that combines the functions of a solar inverter and a battery inverter. Additionally, all transmission grid scale applications require custom designs due to their specific energy requirements and installation environments. These challenges make it difficult to create energy storage solutions that are easy to purchase, deploy, and use efficiently.

Means for Solving the Problems

[0007] Despite the development in this field, the existing technologies and solutions do not adequately address these issues and pose significant obstacles to the widespread adoption of renewable energy. Therefore, there is an urgent need for energy storage solutions that are economic, efficient, have a long service life, are easily provided, and adaptable across various application areas. The object of the present invention is to address these drawbacks and provide such a solution.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2A

Figure 2B

Figure 3

Figure 4A

Figure 4B

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Mode for Carrying Out the Invention

[0009] Figure 1 is a top view of an extruded aluminum tube for battery storage, showing the extruded aluminum tube designed for battery storage as seen from above. This figure reveals an efficient mechanism and safety means considering this battery system. The main components include battery cells and PCBs, extruded screw holes, double insulation, PCB clamps, and overlapping insulating layers. These features are safe, well-insulated, and guarantee a robust environment for the cells, while providing a stable framework for electrical balance.

[0010] Figure 2A is a perspective view of an AC battery storage grid, providing a perspective view of the AC battery storage grid at an angle. This grid is composed of a 4×7 array of aluminum tubes and is configured to enable a stepped AC voltage. The important features include switching positions for generating a stepped voltage, interconnections to a compensator, and the compact dimensions of the system. The figure shows how the grid converts stored DC power into a usable AC output and the function of the compensator that creates a sine wave suitable for use.

[0011] Figure 2B is a perspective view of a DC battery storage grid, similar to the AC grid in Figure 2A, showing a DC battery storage grid designed to generate a DC voltage for an inverter. The main features shown include interconnections between cell banks, flying capacitors for balance, and a DC output array to the inverter. This figure emphasizes the flexibility of the system in providing various electrical configurations and clarifies the role of the inverter in converting a high-voltage DC output into AC power.

[0012] Figure 3 shows an alternative tube configuration for quadruple cell storage, representing an alternating tube configuration, showing a rounded-corner square design that houses four cells, doubling the storage capacity compared to the tubes of the design in Figure 1. The main features include increased redundancy, reduced balancing elements for parallel connection in each layer, and the use of fusible links to ensure system safety and reliability. Despite the increased storage capacity and redundancy, this configuration effectively manages potential risks such as excessive current or arc flash.

[0013] Figure 4A is a perspective view of an AC battery storage grid in quadruple cell storage, showing a 3D view from above of the grid layout using a tube design modified from Figure 3 to generate a stepped AC voltage. This layout demonstrates the conversion of stored DC power to a usable AC output via the printed switching positions. This figure also shows the interconnection to a compensator, which is important for stepwise conversion of the AC to a sinusoidal wave suitable for use. Despite the increased storage capacity, the system maintains a compact design with the same dimensions as previous designs. This more compact arrangement increases the storage capacity compared to Figures 2A and 2B.

[0014] Figure 4B is a perspective view of a DC battery storage grid in a quadruple cell, which reflects Figure 4A but is consistent with a DC electrical configuration designed to generate a DC voltage for an inverter. This grid configuration shows the interconnection between cell banks, flying capacitors for balancing, and the arrangement of high voltage DC output to the inverter. As in Figure 4A, the system design maintains a compact size and layout, showing modified aluminum tubes that house the quadruple cell configuration. With increasing storage, it manages to fit approximately 14% more energy storage in the same volume.

[0015] Figure 5 is a side view of a dual-tube configuration, showing the side of a dual-tube battery storage system. Here, the cells as well as the balance and monitoring board are housed within this structure. As main features, it includes a coach bolt for fixing a printed circuit board (PCB), cells, and an edge connector, a balance and monitoring board (BMS) with bronze terminals for electrical connection, a PCB fuse plate, and an insertion part fastened to a spring at the tube end. This figure conveys a complete overview of the dual-tube configuration, showing the importance of each component and its role in the system.

[0016] Figure 6 is a schematic diagram of a PCB device for a stepped sine wave approximation waveform, showing a schematic layout of a PCB designed to generate a stepped sine wave approximation waveform mainly using N-channel MOSFETs.

[0017] As important aspects, it includes a copper protection part to prevent damage to the substrate due to a cell short-circuit event, a reference voltage of the MOSFET driver to prevent unwanted switching, a plurality of 100V switching MOSFETs wired in parallel to reduce switching resistance, and a connector to a battery management system (BMS) PCB string.

[0018] This schematic diagram also emphasizes the presence of an "optimizer". The optimizer has two functions. It controls the energy storage cells to generate an approximation waveform with high power conversion efficiency and operates with a compensator to manage the switching timing in the charging and discharging cycles. Overall, Figure 6 provides a comprehensive detailed plan of the PCB design and its integrated role in the energy storage system.

[0019] Figure 7 is a schematic diagram of a high-voltage DC PCB device for use with an inverter, showing a PCB device designed for a flying capacitor balancer intended to maintain the balance of a series-connected cell string. Features to note include a copper protection part to ensure safety against cell short circuits, a balancing capacitor with a positive temperature coefficient (PTC) thermal fuse for cell string and current limiting, voltage monitoring to adjust the switching frequency, and 28 connectors for the PCB string in a battery management system (BMS). The figure illustrates an efficient design implementation for improving the safety and reliability of the system, showing how all interconnection paths extend through the PCB, eliminating the need for external wiring.

[0020] Figure 8 is a schematic diagram of a switching mechanism for connecting cells to Mux channels, providing details of the switching mechanism utilized to connect cell terminals to a multiplexer (mux) channel. Key elements include a resistor-capacitor pair (item 25) that controls the state of the mux's MOSFET, an unsaturated NPN transistor (item 26) designed to prevent potential damage from voltage noise or excessive mux current, a continuous reverse emitter-base junction (item 27) that enables the mux to stay ON for the intended period, a dual channel for accessing a single cell, and a shutdown mechanism for power conservation. The figure emphasizes the complexity of the switching mechanism and the importance of each component in managing the connection of cells to the mux channel in a robust and overload-protected manner.

[0021] Figure 9 is a schematic diagram of a shielding and grounding device for an energy storage pillar, providing details of the shielding and grounding device of the energy storage pillar. This configuration is important in maintaining the safety and electromagnetic compatibility (EMC) standards of the pillar. The main elements include two wiring connections (L1 and L2), a secondary common mode choke for EMI suppression (item 30), a direct connection to the shield of L1 for a common point (item 31), a primary common mode choke for high-frequency noise suppression (item 32), an overall shield for the compensator and optimizer PCBs (item 33), a shielding plate attached to the inside of the cover (item 35), and a metal spring cover for EMC shielding and structural safety.

[0022] Figure 10 is a detailed view of an injection-molded bottom cover and a spring cover, providing details of the injection-molded bottom cover and the spring cover. These components are important for the overall safety and functionality of the energy storage pillar, ensuring reliable interconnection of the cells and facilitating cell installation and removal. The important elements include a double seal (item 36) for protection against water ingress, an opening (item 37) for cell insertion, screw holes (item 38) for fixing the tube, a spring clip (item 11) for locking the spring cover, and a durable corrosion-resistant spring cover (item 12) providing an efficient shield. The figure clearly shows the in-depth considerations behind each design decision, reflecting the emphasis on protection, proximity, and efficient shielding.

[0023] Figure 11 is a detailed view of the base area of the energy storage pillar, providing a detailed breakdown of the design and structure in the base area of the energy storage pillar, and clearly showing the basic features that contribute to the stability, easy accessibility, and protection means of the system. This design shows a robust base plate (item 40), which is designed for versatile setting options and serves as a functional hinge for convenient access while ensuring the stability of the system, complemented by stainless steel pins (item 42). This design also incorporates a clear cell access opening, a special recess (item 44) in the base plate for housing a foam seal to prevent intrusion, and the application of a reinforced insulation of extruded polycarbonate (item 45) to reinforce the strength and durability of the entire system.

[0024] Figure 12 is a diagram showing the plug-and-play pillar and pallet design, providing a comprehensive description of the plug-and-play features of the pillar and pallet within the energy storage system. Consideration of this design includes cross braces or locking devices for improved stability and system reliability, air flow and ventilation under the pallet for optimal thermal management, plug-and-play interconnections that facilitate efficient energy transfer and redundancy, quick-release connections that simplify system setup and maintenance inspections, space for the fork section of a standard forklift to improve system portability, lifting points on the pillar to enable easy replacement of the pillar, and a standard size that fits a 10-foot-high square marine transport container. The elements of this design emphasize the easy setup, portability, and maintenance inspection of the system.

[0025] Figure 13 is a diagram showing the wiring of the pillar-based energy storage system, providing an overall view of the possible wiring configurations for the pillar-based energy storage system, emphasizing its flexibility, self-organizing autonomous performance, various layout options for achieving various levels of redundancy and voltage requirements. These layouts include typical star / delta 240V with redundant loops ac3x3 pillar pallet representing the system (upper left), Delta 1000V with a single redundant loop ac 4x3 pillar pallet exemplifying the system (upper middle left), Delta 1000V with horizontally parallel pillar loops ac 4x4 pillar pallet showing the system (lower left), and Delta 1000V with multi - layer redundancy ac Including a 4x4 pillar pallet with a 2x2 pallet in a 10 - foot shipping container (right), showing. In particular, the software that manages the system assists in charge distribution by finely adjusting the voltage and controlling each current flow across the pillars. This system also incorporates a load - testing function for connection either before commissioning or during maintenance checks. This detailed diagram clearly shows the adaptability and responsiveness of the system and its ability to meet diverse operating requirements.

[0026] Referring to the figure, an energy storage system for use connected to either a main electric power transmission network (on - grid) or an independent electric power transmission network (off - grid) is shown.

[0027] The present invention develops from concepts represented in previous patents, including the following: 1. "POWER CONVERSION METHOD AND SYSTEM" of International Publication No. WO 2015 / 184512 2. "SYSTEM AND METHOD FOR DETECTING CONNECTOR FAULTS IN POWER CONVERSION SYSTEM" of International Publication No. WO 2015 / 184511 3. "METHOD FOR CONTROLLING A POWER CONVERSION SYSTEM" of International Publication No. WO 2016 / 008003, and 4. "BATTERY PACK" of International Publication No. WO 2019 / 113647.

[0028] These patents mentioned above are incorporated by reference herein. The present invention introduces several layers with additional functionality and practicality, improving previous patents in a significant way.

[0029] 1. The energy storage system represented herein features a large-capacity design with improved electromagnetic interference (EMI) and electromagnetic compatibility (EMC) compliance. Compared to the battery packs represented in the past, simplified cell replacement and setup are also proposed. These improvements are realized by the features emphasized in the claims and the following description.

[0030] 2. The present invention proposes a system with series and parallel connections, providing improved redundancy and storage options in commercial and public facilities. The details of this design are elaborated in the subsequent claims and description.

[0031] 3. This energy storage system also provides improved surge protection and the ability to test functions compared to previous systems. The outlines of these improvements are emphasized in the later claims and description.

[0032] The starting point of the present invention is the energy-storage system, which is the most important aspect of the present invention. This system comprises a plurality of elongated compartments, each of which is designed to accommodate a string of energy storage cells. Each compartment is equipped with an accessible opening, especially designed to facilitate the easy setup and removal of these storage cells.

[0033] These compartments are constructed to house two or more storage cells arranged adjacent to each other within their scope. Additionally, this system incorporates a holding mechanism that firmly presses and holds the strings of cells together. This device ensures a reliable current path and forms the backbone of this energy storage system.

[0034] Furthermore, this system integrates a sophisticated balancing mechanism. This mechanism features a balancing system and includes electrical tabs that connect to the junctions of adjacent cells. This mechanism also has means for moving charge into or out of these tabs. This enables the charging and discharging of the cells and thereby harmonizes their voltages. This complex but efficient process enables a long string of cells to be balanced without relying on complex wiring.

[0035] In subsequent sections, the detailed aspects of the invention will be further elaborated upon, along with its operation, settings, and beneficial characteristics.

[0036] Features are added in accordance with the illustrated description of the present system below, which describes the most well-known embodiments as non-limiting examples.

[0037] Figure 1: Top view of an extruded aluminum tube for battery storage Figure 1 is a bird's-eye view of an extruded aluminum tube, specifically designed to house a battery storage section. The layout and features shown in this figure provide considerations regarding how this configuration supports the efficient operation and safety of the battery system.

[0038] Main elements of Figure 1: · Battery cells and PCB: This tube is designed to hold two aligned battery cells (item 1). These cells are separated by a printed circuit board (PCB) (item 2) that plays a role in the electrical balancing of the battery system. · Extruded screw holes: This design incorporates extruded screw holes (item 4) that facilitate a secure attachment to an injection-molded cap. These screw holes are integrated to maintain structural integrity and ensure a tight fit. · Insulating part: An important feature of the tube design is to provide a second double insulating part (item 3) between the cell and the tube. This additional safety measure provides a robust barrier that reduces the risk of electrical interference or shock. The additional insulating layer also protects against corrosion and cells with poor quality or damaged shrink wrapping. · PCB clamp: This layout also includes PCB clamps. They are advantageously positioned to provide support for the PCB while improving insulation. These clamps not only maintain the position of the PCB but also ensure its safety. · Duplicated insulating layer: In particular, the duplicated insulating layers (items 3 and 5) are set to further improve safety standards. This layer is particularly important in preserving the creepage distance, i.e., the shortest path between two conductive components or between a conductive component and the interface of the equipment, measured along the surface of the insulating part.

[0039] The layout shown in Figure 1 provides a comprehensive overview of the complex design of the extruded aluminum tube and shows the considerations behind the tube design, especially in ensuring the safety and usability of the battery storage system. [Figure 2A: Perspective view of the AC battery storage grid]

[0040] Figure 2A provides a comprehensive perspective view of the organized grid structure without the axis and shows the efficient use of the extruded aluminum tube. The figure shows a 4×7 grid arrangement accommodating 28 tubes and is consistent with a schematic diagram (Figure 6) showing the details of the electrical device for generating a stepped AC voltage.

[0041] Main elements of Figure 2A: · Stepping between battery banks: (Item 7) refers to the switching positions for generating a stepped voltage and indicates the conversion of stored DC power into an available AC output. As can be verified, the stepping is transverse to the layout of the battery banks. If the left (Item 9) is set to 0V with consecutive cells in each 72V tube, the output voltage of the right (Item 9) can range from -504V to +504V. · Interconnection to the compensator (Item 9): This feature visualizes where the interconnection to the compensator mounted on the subsequent PCB is located. The compensator is an important component that converts stepped AC into a sinusoidal wave suitable for use, adjusts and regulates the voltage levels in tandem with a stepped mechanism, thereby ensuring the compatibility of the power electronics system. · Dimensions and structure: This system includes injection-molded end caps and is approximately 1900 mm in height, 300 mm in width, and 300 mm in depth. While including multiple battery compartments, it emphasizes the compactness of the system. The figure presents an extruded aluminum tube (Item 6) that can house battery cells and the associated PCBs for a complete AC system. [Figure 2B: Perspective view of the DC battery storage grid]

[0042] Figure 2B, parallel to Figure 2A, is aligned with the DC electrical configuration (Figure 7) and presents the same grid arrangement as the battery storage compartments. It is a high-voltage (HV) system designed to generate the DC voltage for use by the inverter.

[0043] Main elements of Figure 2B: · Interconnection between battery banks (Item 8): The figure shows where the interconnection between the cell banks and the position of the flying capacitor for balancing is electrically located on the PCB. This also presents an interconnection transverse to the layout of the parallel battery banks. · DC Output Device to Inverter: (Item 9) indicates where the interconnection to the inverter in the subsequent PCB is located. This inverter plays an important role in converting high-voltage DC output to AC power. · Dimensions and Structure: Consistent with Figure 2A, Figure 2B presents the same compact dimensions and layout. The extruded aluminum tube (Item 6) is also shown, indicating the storage capacity of the system and its well-constructed design.

[0044] Collectively, Figures 2A and 2B provide a comprehensive overview of the various electrical configurations that can be realized with this battery storage system, highlighting the power output, system design, and flexibility in possible I / O devices. [Figure 3: Alternative Tube Configuration for Quadruple Cell Storage]

[0045] In Figure 3, an alternative to the device emphasized in Figure 1 is introduced, explicitly showing a tube with a more rectangular shape and rounded corners, designed to accommodate cells. Different from the housing of the two cells in Figure 1, this tube is devised to house four cells.

[0046] Main Elements of Figure 3: · Quadruple Cell Housing: This configuration houses four cell layers within the tube, effectively doubling the storage capacity compared to the tube layout of the two cell layers in Figure 1. This design progresses from a software-driven process that simplifies the redundancy mechanism and balances the cells in four parallel double tubes (four double tubes are shown vertically in Figure 2A) to a mechanism where redundancy is achieved through four parallel cells with a huge link to the balance PCB, through four parallel cells. · Reduction of Balancing Elements: The same orientation in the four cells facilitates parallel connection in each layer, significantly reducing the number of balancing elements required. This configuration (four parallel cells and twelve series cells (a total of 24 cells considering the return path)) guarantees a normal voltage similar to Figure 1, provides improved redundancy, and reduces the number of balancing elements to approximately one-fourth. · Risk Management: Despite the improved storage capacity and redundancy, this configuration poses potential risks such as excessive current or arc flash due to parallel cells in each layer. A complete short circuit is mitigated by a fusible link. · Fusible Link: The connection points of the cells are equipped with fusible links that lead to the BMS PCB. This is because this link must only conduct balanced current, and the fusible link can have a relatively high resistance without significantly losing efficiency. Unlike through-current fuses that only require minimal resistance to reduce efficient operation and heat, these links are only exposed to relatively high currents during abnormal events. Therefore, their high resistance levels and low current capacity are suitable for and contribute to the overall safety and reliability of the system. · Consistency with Figure 1: Apart from the above changes, the layout and components in Figure 3 are mostly consistent with the layout and components shown in Figure 1.

[0047] Representing this modified configuration, Figure 3 emphasizes a simplified design for energy storage exchange, improves redundancy, reduces the number of balancing elements, and effectively manages associated risks. This flexible design avoids imposing reliability on a specific power conversion method, thereby enabling an adaptable system configuration based on specific requirements. [Figure 4A: Perspective View of a Quadruple Cell AC Battery Storage Grid]

[0048] Similar to Figure 2A, Figure 4A provides a comprehensive perspective view of the grid layout without the axis. However, this figure features a modified tube design and is specifically designed to house four battery cells and conforms to a schematic diagram (Figure 6) for generating a stepped AC voltage.

[0049] Main Elements of Figure 4A: · AC Output Device: The switching positions for generating a stepped voltage are marked as (Item 7). This emphasizes the conversion process from the DC power stored in the quadruple cell to the available AC output. The storage density is slightly increased using this device, enabling an additional switching layer, which is enabled in steps from -576V to +576V at 72V per two cell tubes across the terminals (Item 9). · Interconnection to the Compensator (Item 9): This figure shows where the interconnection to the compensator on the adjacent PCB is located. The compensator is an important component that converts the stepped AC into a sinusoidal wave suitable for use, collaborates with the stepped means to adjust and regulate the voltage level, and ensures the compatibility of the power electronics system. The compensator can be either an active element as mentioned in the related patent or a passive inductor that forms PWM as needed to generate the desired quality of the sinusoidal wave. · Dimensions and Structure: Similar to Figure 2A, the dimensions of this system include an injection-molded end cap and are approximately 1900 mm in height, 300 mm in width, and 300 mm in depth. Despite the increased storage volume using the quadruple cell, this system maintains a compact structure. This figure also shows the modified aluminum tubes (Item 6), which can accommodate the quadruple cells and their corresponding PCBs. · Storage Capacity: This device is compatible with a storage that is approximately 14% more in the same volume. [Figure 4B: Perspective View of the DC Battery Storage Grid of the Quadruple Cell]

[0050] Figure 4B is consistent with the DC electrical configuration similar to Figure 2B. It shows the grid arrangement of the battery storage section of the quadruple cell and a system designed to generate the DC voltage for use by the inverter.

[0051] Main Elements of Figure 4B: ·Interconnection to the inverter (Item 8): This feature specifies where electrically on the PCB the interconnection between the cell bank and the position of the flying capacitor for balancing is located. ·DC output device: (Item 9) refers to the interconnection to the inverter in the subsequent PCB. This inverter is important for converting the high voltage DC output to AC power from the quadruple cell configuration. ·Dimensions and structure: As shown in Figure 4A, Figure 4B involves a modified aluminum tube (Item 6) that maintains the same compact dimensions and layout and can accommodate the quadruple cell configuration. ·Storage capacity: This device is compatible with storage that is approximately 14% more in the same volume.

[0052] Both Figure 4A and Figure 4B provide an inclusive overview of different electrical devices made possible using this quadruple cell battery storage system. They show the potential for improved voltage output, storage capacity, and flexibility in system design, while on the other hand indicating the possible terminal polarities. [Figure 5: Side view of the dual - tube configuration]

[0053] Figure 5 provides a side view of the dual - tube configuration used in the battery storage system. At the top of this configuration, there is an injection - molded cover attached to all 28 tubes. The cover itself is not shown in this figure, but its bottom edge is marked as (Item 23).

[0054] Main elements of Figure 5: ·Coach bolts and PCB: Coach bolts (Item 10) bolted to the cover can be seen in the figure. Held in place by their corresponding nuts, these bolts fix the printed circuit board (PCB (Item 15)) via star washers or split washers, and they are further tightened by a second set of associated nuts. · Cells and Connectors: This figure shows a cell (Item 1) together with a card edge connector (Item 14) that holds the balancing and monitoring board (Item 2). The balancing and monitoring board is firmly pressed into the edge connector by an injection-molded pressure plate (Item 17). This pressure plate is pushed in by the top cell, which then pushes the PCB into the connector. · Balancing and Monitoring Board (BMS): The balancing and monitoring board (Item 2) comprises a plurality of segments, each of which features phosphor bronze electrical terminals for making electrical connections at the junction points between cells. Each segment serves the role of monitoring and balancing each end of adjacent cells. Additionally, a flexible junction spans across subsequent cells before connecting to the next BMS segment. · Spring-Retained Insert and Fuse Plate: Located at the end of the tube is a spring-retained insert. This insert (not shown) is made of injection-molded material and features a PCB fuse plate (Item 21) that connects the ends of the cells. The spring is shown as (Item 22), the terminals are shown as (Item 19), and the fuse is shown as (Item 20). This fuse can be set after the cells are set and the polarity is confirmed. This fuse makes an electrical connection across the ends of the cells and protects the cells from excessive current that can result from system damage or failure.

[0055] Figure 5 provides an overall view of the dual-tube configuration and details the important components and their placement within the system. It helps in understanding the electrical connections, mechanical settings, and the role of each component within the overall system. [Figure 6: Schematic of a PCB device for a stepped sine wave approximation waveform]

[0056] Figure 6 represents a schematic diagram showing the layout of a PCB, which is designed specifically to generate a stepped sine wave approximation waveform. This device mainly uses N-channel MOSFETs (Metal Oxide Semiconductor Field Effect Transistors), and their drains are connected to secure connections in four dual-tube cells as depicted in Figures 1 and 2A, and are shown in the figure using a standard battery symbol with a positive short segment at the top.

[0057] Main elements of Figure 6: · Copper protection: This PCB incorporates sufficient copper such that when current flows through the positive and negative vertical schematic lines, it ensures that a short circuit event in the cell activates the fuse (shown in Figure 5) before any damage is done to the substrate itself. · Reference voltage for the drivers: The drivers for all connected MOSFETs, including those used for the balance within the tube, are referenced for their own power supply to prevent unwanted switching caused by a current of 0V. The sources of the MOSFETs are connected to the negative cell string, while their drivers are connected to the 0V power supply of the relevant microprocessor. · Parallel switching of MOSFETs: This schematic includes multiple 100V switching MOSFETs that are wired and driven in parallel. This configuration reduces the switching resistance and decreases the overall losses. This device increases reliability by eliminating the need for external wiring as all the interconnection paths are incorporated within the PCB. · Connectors for the BMS PCB string: This PCB features 28 connectors for the PCB string in the Battery Management System (BMS). Each string corresponds to a dual-tube and follows the configuration shown in Figure 2A. Conversely, if the design follows Figure 4A, the routing selection will be different and there will be 16 connectors instead.

[0058] Although not shown, the PCB communicates with the system's control compensator and, under its control, is adjusted to generate the main approximation waveform. This device is called an "optimizer" for its two functions. · This optimizer controls energy storage cells, switches them, and generates an approximate waveform using a very high power conversion efficiency. A slow switching frequency only results in normal power consumption, while the series resistance in all the combined MOSFETs, which in this case are four parallel 3.5 mΩ devices, results in a resistance of less than 2 mΩ per switching H-bridge. This results in less than 14 mΩ across all the cells in all seven optimizer banks. Thus, the losses at 20 A and 240 V rms are less than 0.1%. This very high efficiency results in correspondingly low heat losses and a function that operates with passive cooling. A small recirculation fan is set inside the cavity that houses the optimizer and the compensator board. This fan operates at a high power level and eliminates the need for ventilation in this case. · The compensator manages the switching timing, maintains the cell bank at a high charge level continuously over a long period while discharging, and does the reverse during the charging cycle.

[0059] In summary, Figure 6 provides a comprehensive overview of the PCB design and interconnectivity. It highlights how the PCB, MOSFETs, and other components cooperate to form a stepped sine wave approximation waveform, manage the electrical flow, minimize losses, and present effective design options for desirable components of the energy storage system. [Figure 7: Schematic diagram of a PCB device for high voltage DC for use in an inverter]

[0060] Figure 7 is a schematic diagram showing a PCB device for balancing a string of serially connected cells using a topology commonly called a flying capacitor balancer. This configuration is intended to generate high voltage DC power for use in an inverter. In this design, N-channel MOSFETs are used, with the drains connected to four dual-tube cells, consistent with the styles of Figures 1 and 2B.

[0061] Main elements of Figure 7: · Copper protection part: This PCB features sufficient copper such that when the cells short-circuit, the current flows through the positive and negative vertical lines, ensuring that the fuse (see Figure 5) blows before the substrate is damaged. · Reference voltage for the driver: The drivers for all connected MOSFETs are referenced for their own power supply, including those used for the balance within the tube, preventing unwanted switching caused by a current of 0V. The source of the MOSFETs is connected to the negative cell string, while their drivers are connected to the 0V power supply of the relevant microprocessor. · Cell string and balancing capacitor: The cell string is connected in series, and the electrolytic capacitor for balancing is connected as shown by item 8. A positive temperature coefficient (PTC) thermal fuse is placed in series with the capacitor to limit the current. An inductor adjusted to the switching frequency can be wired in series with the capacitor, enabling the use of smaller capacitors with lower values, thereby allowing options for film or ceramic capacitors. · Voltage monitoring: Monitoring of the string voltage is provided, and the switching frequency is adjusted to limit the average current according to the voltage difference across the string. The power transferred through the flying capacitor is proportional to the switching frequency in an unregulated system, whereby the switching period of the flying capacitor is adjusted in proportion to the voltage difference between the measured maximum and minimum string voltages. When an inductor is used, the frequency changes according to a formula calculated taking into account the Q factor of the resonant circuit. · Connector for the BMS PCB string: This PCB has 28 connectors for the PCB string in the battery management system (BMS), with one string per dual tube aligned with the arrangement in Figure 2B. If following the arrangement in Figure 4B, the routing will be different and there will be 16 connectors instead. · No external wiring: All interconnection paths proceed through the PCB, eliminating the need for external wiring.

[0062] Overall, FIG. 7 provides a clear view of the PCB device for generating high voltage DC for inverter use. This device effectively manages cell balancing, current limiting, and voltage monitoring. It demonstrates how efficient design choices can simplify the structure and operation while improving the safety and reliability of the system. [FIG. 8: Schematic diagram of the switching mechanism for connecting cells to the Mux channels]

[0063] FIG. 8 shows a schematic diagram detailing the switching mechanism used to connect cell terminals to the multiplexer (mux) channels. This figure reveals the complex interactions of the various components that create the Rotec four-wire control mechanism and enables an efficient overload prevention switching mechanism that supports replaceable cells in large-scale energy storage systems. The switching regulators that drive the MuxChA and MuxChB channels and the accurate ADCs monitoring voltages in these lines are not shown. The selection of the mux channel and its connection to the cell connection point involves the associated regulator driving to an approximation of the expected cell voltage and then connecting to the mux of the nearest cell by command.

[0064] Main elements of FIG. 8: · Resistor-capacitor pair (item 25): This pair consists of a resistor that serves to limit the current and a capacitor that blocks the potential difference between the driver that toggles the state of the mux's MOSFET (metal-oxide-semiconductor field-effect transistor). This driver alternates between the high and low states, thereby turning the selected mux ON or OFF respectively. · Unsaturated NPN Transistors (Item 26): These transistors are designed to prevent the mux from turning ON when the voltage of the connected cell is outside the range of the common mux potential, and to disable the MOSFET when the difference between the cell voltage and the voltage of the mux channel exceeds the voltage set by the unsaturation sensing resistor connected to the base of these transistors. This feature enables the first connection to the nearest cell and prevents potential damage from voltage noise or excessive mux current. This unsaturation mechanism ensures that any connection is bistable, that cells close to the mux potential are turned ON more strongly, pulling the mux voltage away from another cell voltage and causing unsaturation in another cell voltage, further turning it OFF. · Continuous Inverse Emitter-Base Junctions (Item 27): These transistors exhibit a sharp knee voltage at approximately 5V, with very low leakage due to their continuous inverse emitter-base junctions, and their standard Zener diodes are not realized at voltages near the point where they turn ON. This feature enables the mux to remain ON for a significant period before it needs to be turned OFF and then ON again, thereby recharging the blocking capacitor (Item 25). · Dual Channel: This figure features two copies of the circuit shown at the top and bottom, which are connected to the positive terminals (the odd and even negative terminals of the serially connected cells) in the even and odd cells respectively. This design has two purposes: - The mux channels are separated by at least 5V (two cells at a minimum charge of 2.5V), encouraging an easy 2.5V unsaturation voltage to be realized using a voltage divider of base resistors. - A single cell can be accessed for charging or discharging, with one mux channel connected to its positive terminal and the other to its negative terminal. · Interrupt mechanism: All muxes can be sent into the deep sleep state to save power. This is achieved by setting a switching regulator that drives the mux channels to a low voltage and then sets enable to a low state. The resistor (item 29) ensures that the gate cannot float high while being enabled.

[0065] In summary, FIG. 8 provides a detailed depiction of the switching mechanism, highlighting the essential roles of each component in smoothly connecting the cell to the mux channel. This figure clearly shows both the complexity of the switching mechanism and the importance of each element in ensuring both the control via two control lines and the unique cell connection mechanism. [FIG. 9: Schematic diagram of shielding and grounding for the energy storage pillar]

[0066] FIG. 9 provides an illustration of the details in the shielding and grounding devices utilized in the energy storage pillar. This assembly is important for maintaining both the safe operation of the energy storage pillar and the compatibility with electromagnetic compatibility (EMC).

[0067] Main elements of FIG. 9: · Two wiring connections (L1 and L2): This figure shows two wiring connections marked L1 and L2. L1 can be the line voltage, or a functional ground or neutral. · Secondary common mode choke (item 30): Positioned above the lead at the entrance point, the secondary common mode choke operates to suppress the transmitted electromagnetic interference (EMI) by reducing the common mode noise current. · Direct connection of L1 to the shield (item 31): L1 is directly connected to the shield at or near the cable entrance point, realizing a common point that can be wired as a functional ground. · Primary common mode choke and filter (item 32): This component is set to suppress high-frequency noise in the system and is related to electronics. · Shielding of the compensator and optimizer PCB (Item 33): The comprehensive shielding covers the compensator and the printed circuit board (PCB) of the optimizer located at the top of the pillar, provides protection, and promotes EMC compliance. · Shielding plate (Item 35): Either a PCB or a solid metal shielding plate is attached inside the injection-molded cover. This shielding is screwed onto the shielding of the aluminum tube (Item 35), creating an electrical interconnection to integrate the aluminum tube into the shielding device. · Metal spring cover at the base: At the base of the pillar, metal spring covers are electrically connected to each other via retaining clips (Item 11 in Figure 10). These clips mechanically and electrically connect the lower ends of the aluminum tubes that hold electrical stepping inside. This device prevents differential voltages at these ends and mitigates potential EMC problems arising from such voltages. This setting does not contribute significantly to Figure 7 but contributes to the EMC shielding for the device shown in Figure 6. These shieldings also serve a safety function, maintaining the structural integrity of the system in case of failures that lead to overheating of the cell.

[0068] Overall, Figure 9 provides a comprehensive overview of the complex shielding and grounding settings within the energy storage pillar, highlighting the contributions to both safety and EMC compliance. [Figure 10: Detailed design of the injection-molded bottom cover and spring cover]

[0069] Figure 10 provides a detailed view of the design and function of the injection-molded bottom cover and spring cover. These important components play a role in fixing the cells within the energy storage pillar, ensuring protection i.e., reliable interconnection, and providing protection against forces applied to the cells to facilitate the process of cell setting and removal.

[0070] Main elements of Figure 10: · Double Sealing (Item 36): The injection-molded cover at the bottom prominently features a double seal around its peripheral edge. This seal plays an important role in protecting against water ingress when the pillar is in the upright position and effectively seals the load area of the cell. · Cell Insertion Openings (Item 37): The cover design includes multiple openings that are matched to the internal dimensions of the tube. These inlets facilitate the process of cell insertion and removal. · Screw Holes (Item 38): Integrated into the cover are holes that are advantageously positioned to fit the screw slots of the tube. Screws inserted through these holes firmly attach the tube to the molded cover, ensuring a robust connection. · Spring Clip (Item 11): Covering the screw holes and held in place by the same screws used to secure the tube is a U-shaped spring clip. These clips feature wings that lock the spring cover (Item 12) in place. These clips can be made into a twist-lock closure (Item 39) that facilitates the removal of the spring cover. · Spring Cover (Item 12): The spring cover and clip are made of stainless steel selected for durability, strength, and corrosion resistance. Their conductivity also provides efficient shielding across the bottom of the pillar.

[0071] In summary, Figure 10 represents the details of the design considerations within the energy storage system, particularly in the construction of the bottom cover. It emphasizes the methods taken to ensure protection, proximity, and shielding within the cell system. [Figure 11: Design in the Base Region of the Energy Storage Pillar]

[0072] Figure 11 provides a detailed view of the actual implementation in the base region of the energy storage pillar. This figure shows the functional elements that ensure stability, easy access, and protective shielding of the system.

[0073] Main Elements of Figure 11: · Base plate (Item 40): The center of the design is the base plate, which can be fixed to the floor using specific screw holes (Item 41). Alternative or additional mounting methods, such as liquid nails or permanent adhesion of two-component epoxy, provide flexibility in the setup process. · Stainless steel pins (Item 42): Embedded within the design are stainless steel pins that serve two functions. First, they help hold the pillars in an upright position to ensure stability. Second, they function as hinges on any one of three axes (left, front, or right), allowing the pillar to lean over the cell for easy access. Additional stabilizing walls with pins, not shown, are inserted into the top of the pillar to ensure that the pillar is not knocked down or blown over. · Opening for cell access: Figure 11 shows a clear opening that allows for easy cell access. All 28 spring covers and retaining caps (Item 43) can be accessed through this opening, simplifying cell maintenance inspections and replacements. · Recess in the base plate (Item 44): A specially designed recess in the base plate houses an expanded foam seal. This seal fits into the double seal of Figure 10, ensuring a tight fit that prevents the intrusion of unwanted substances. · Insulation reinforced with extruded polycarbonate (Item 45): The aluminum tube is covered with insulation reinforced with extruded polycarbonate. This insulation is shaped with a recess and, similar to a roof panel, improves the structural strength and durability.

[0074] In conclusion, Figure 11 clarifies the design considerations incorporated into the base region of the pillar, aiming for stability, easy access to the cell, and protection from environmental factors. [Figure 12: Plug-and-play pillar and pallet design]

[0075] Figure 12 provides an overview of the main elements in a standard pillar and pallet, highlighting the plug-and-play features of these components within an energy storage system.

[0076] Main elements of Figure 12: · Cross braces or locking devices: This design integrates a mechanism such that all pillars are either cross-braced or interlocked, causing adjacent pillars to operate as a single physical module. This can include cross-bracing the straps, connecting the bottom of a pillar to the top of an adjacent pillar, or interlocking in a way that prevents the pillars from sliding perpendicular to each other when tightened together. This feature improves the stability of the moving pillars and eliminates movements that could compromise the system's reliability. It is important in preventing the top ring or displacement of the pillars. A preferred locking device (not shown) is in the shape of an H, rotated 90° horizontally, installed between the pillars, providing space for air flow, and locking the legs of this H shape above and below an injection-molded cover at the top. · Air flow and ventilation under the pallet: This design facilitates efficient thermal management within the system by guiding cooling air over the sides of the pillars. The space under the pillars, which also houses the fork parts of the forklift, shares the air under the pillars. The risers that lift the pallet are equipped with holes or voids that enable the crossing of the air flow. These two functions effectively maintain the optimal performance of the energy storage cells. · Plug-and-play interconnections: Each pillar is equipped with multiple high-power terminals designed for both input and output. This design choice allows for sufficient current paths and ensures effective energy transfer and redundancy. To complement these, fiber optic lines are introduced in parallel to the electrical connections and also serve as redundant transmission paths to reinforce the system's reliability. · Quick-release connections: This design includes quick-release connections for both transmission and high-current terminals. This connection simplifies the system setup, configuration, maintenance checks, and upgrades. · Space for standard forks: The pallet is designed with sufficient clearance below for the forks of a standard forklift, facilitating easy movement. This feature improves the portability, setup, and flexibility of the system. · Pillar lifting points: To facilitate easy pillar replacement, the lifting points are integrated into the pillar design. Once the pallet is relocated to the service area, these lifting points enable easy removal and replacement of the pillars. · Standard size: The preferred pallet is of standard size and can accommodate 4×4 pillars, such that four pallets fit neatly into a 10-foot-high cube shipping container.

[0077] In summary, Figure 12 highlights the design elements that contribute to the easy setup, portability, and maintenance inspection of the pillars and pallet. It clearly demonstrates the plug-and-play nature of the energy storage system. [Figure 13: Wiring of Pillar-Based Energy Storage System]

[0078] Figure 13 shows a possible wiring configuration for an energy storage system that utilizes a pillar structure. The flexibility of the system is emphasized, starting from the function of the pillars to self-organization during startup. This self-organization process enables the pillars to autonomously determine the wiring topology before the user defines the allowable operating parameters such as current and voltage. During this self-organization, the pillars electrically exercise their outputs in communication with their adjacent counterparts. This action ensures that the electrical interconnections match the topology defined by the detected communication interconnections. The device presents a schematic layout to the user and verifies whether the wiring is implemented as expected, visually indicating any faults or incorrect interconnections.

[0079] Main elements of Figure 13: · 3×3 pillar pallet (upper left): This arrangement is a typical star / delta 240V with redundant loops acRepresents a system that ensures continuous operation in the event of a single pillar failure. The software of this system subtly adjusts the charge distribution across the pillars within these loops by changing the voltage to control each current, increasing the voltage in overcharged pillars and decreasing the voltage in undercharged pillars. In this configuration, each delta spans two pillars, and one pillar reaches the star point. · 4×3 pillar pallet (center left): 4×3 pillar pallet (center left): This layout has a delta of 1000V ac Represents a system characterized by a single redundant loop surrounding these deltas. Similar to the 3×3 pillar pallet, this design preserves system operation even in the event of a pillar failure. The software orchestrates the charge distribution and adjusts the peripheral current between the pillars (in addition to any current entering or leaving the system) by subtly regulating the voltage across the delta loop. In this setup, each delta spans four pillars. · 4×4 pillar pallet (lower left): This configuration has another delta of 1000V ac Represents a system that only includes loops between horizontally aligned and parallel pillars. When charge transfer between deltas is required, the system utilizes an externally connected converter. The software manages the charge distribution between the deltas by adjusting the voltage to control each current, increasing the voltage in overcharged pillars in one delta string and decreasing the voltage in undercharged pillars in another delta string. The external converter facilitates shunting in this arrangement. · 4×4 pillar pallet with a 2×2 pallet in a 10 - foot transport container (right): Delta 1000V acRepresenting this layout, it exhibits multi-layer redundancy with four parallel and horizontally arranged pillars and loops both around the three-way delta. The movement of charge between deltas operates as described in the 4x4 pillar palette. The software aids the commissioning process by automatically mapping out the topology. As shown here, two deltas contain five pillars in series and the third delta contains six pillars. Each pillar adjusts the current and they either contribute individually or draw from the power source to maintain an evenly distributed charge level and follow a predefined charge and discharge profile.

[0080] When loops are present, the system incorporates features for load testing the connections either before commissioning or during maintenance checks. First, the system disconnects the connection from the power source. The pillars within each loop alternately output a safe and extremely low voltage, conduct a high test current through the system, effectively making the untested pillars play a passive role, divert the current, or alternatively operate all the pillars for testing, providing a positive step and an adjacent negative step, or the voltage around the loop. Thereby shortening the total test period. This test continues long enough to heat any high-resistance joints and uses a thermal camera to facilitate defect detection. After the test and verification are complete, the operator can end the test mode and reconnect the system to the power source.

[0081] Finally, Figure 13 emphasizes the flexibility and adaptability of the system, shows the range of configurations, realizes varying levels of redundancy, facilitates pre-operation integrity testing and functionality, and meets diverse voltage requirements. [Another Feature (not shown) in the Pillar-Based Energy Storage System]

[0082] Additional features incorporated within the pillar-based energy storage system collectively improve the overall performance, reliability, and ease of maintenance of the system.

[0083] Main Aspects: · Parallel Pillars: The pillars can be arranged in parallel to enhance reliability, increase storage capacity, or increase current capacity. In this configuration, the pillars operate in unison, summing their voltages to provide or consume the required power. · Charge Management: The pillars in a string or loop communicate their voltages and perform delicate individual adjustments to manage their power flow and the resulting charge levels, thereby ensuring an optimal charge distribution throughout the system. · Test Mechanism: The pillars can undergo various test procedures such as disconnecting their connections from the power system, high-current tests, high-voltage tests of the pillars, and high dV / dt pillar voltage load tests. These tests are essential for monitoring the performance of the pillars and identifying potential aging degradation or component failures. · Leakage Test: The system performs a leakage test to detect any leakage current in the system, particularly between the cells and the tubes surrounding them. It can signal the ingress of moisture or degradation of the insulation. These tests are carried out during the cutoff phase or when no current needs to flow through the pillars. The pillars drive a high or low voltage with respect to L1 (shown in Figure 9), and then isolate their corresponding MOSFETs. By measuring the decay of the cell voltage and comparing it with the rate of decay estimated from a known current such as the current required for the voltage requirement, any leakage current is confirmed or alternatively considered insignificant. This process ensures that any significant leakage is immediately identified and addressed. · Double Insulation: Each pillar is equipped with a dual layer of double insulation and overlapping insulation to ensure an appropriate creepage distance, providing enhanced protection for the internal cells. · Cell replacement: The system design significantly simplifies the cell replacement process. In the hinge formed by the stainless-steel pins (item 42), the base plate (item 40), and the injection-molded cover at the bottom (Figure 10), by tilting the pillar downward, access is allowed to the area where the retaining clip (item 11) is pressed to release, disengaging the cell's spring pusher (item 12). After this step, the spring mechanism can be removed to allow access to the end-plate PCB. This proximity facilitates the easy removal of the old cell and the setting of the new cell. · Mounting and wiring: For large storage pillars, it can be slightly changed with respect to the design shown in Figure 11. Specifically, the hinge device may not be included if it is considered unnecessary. The pillar is designed to fit neatly into the recess of the pallet, which simplifies the process of setting, delivery, and removal. Additionally, the pillar is designed with plug-and-play features to accommodate dual wiring and transmission paths for the incoming and outgoing connections. It is also important to note that the pillar attached to the pallet does not require an additional base plate, as the pallet performs this function. Additionally, the lifting points incorporated into the injection-molded cover at the bottom (see Figure 10) allow a dedicated removal trolley to lift and easily remove the pillar. · Overvoltage surge protection: The pillars are designed to protect themselves from overvoltage surges mainly by opening their MOSFETs into an open circuit. This response acts as a resistance to the surge voltage and uses the body diodes in the open-circuit MOSFETs to change the direction of any resulting current through the storage capacitors of the cells and the compensator. During a surge event, the compensator monitors the surge current and voltage in its wave storage capacitor while: - A series of specialized sacrificial MOSFETs can be activated to self-destruct as a final protection measure. These back-to-back sacrificial MOSFETs are fully turned on during normal operation. However, when a surge occurs and the compensator can no longer absorb the surge, they are driven off, and the instantaneous self-destruction due to the additional voltage does not cut off the surge. This action provides resistance to larger further voltage surges, thereby shielding the compensator and the rest of the system from potential damage. - Alternatively, a metal oxide varistor (MOV) can be set across the compensator and the back-to-back MOSFET array between the compensator and the nearest optimizer. The MOV has a voltage that is fully turned on below the voltage of the combined back-to-back MOSFETs, combined with the maximum voltage that the compensator can handle. In this setting, the MOV carries the surge current and further protects the system from damage using the compensator and an additional layer of MOSFETs that resist the voltage.

[0084] Finally, emphasize the refined design features and the protection integrated within the pillar-based energy storage system, demonstrating its robustness, operational flexibility, and ease of maintenance and inspection. [Additional features (not shown) for high operating voltage (MV or HV)]

[0085] High voltage operation requires additional features to equip the pillar-based energy storage system with a higher operating voltage. These features embody a proactive stance towards system compliance, safety measures, and electromagnetic compatibility (EMC).

[0086] Main aspects of MV or HV: · Additional insulation: When a higher operating voltage is required, a third layer of insulation is incorporated. This additional layer can be advantageously placed between pallets or used to line the transport container or available space, improving the safety and reliability of the system. · Safety measures: Special precautions are implemented during operation to protect personnel from potential exposure to components of the high-voltage system. These measures may include setting entrances, doors, locks, or warning signs to ensure the reliable and safe operation of the system. · EMC compensation: In high-voltage applications, electromagnetic compatibility is managed through the use of shipping containers that act as Faraday shields or by using dedicated shielding sections. Active compensation can be avoided in this device, and the system generates a pure sine wave through the stepping included in the PWM in series-connected chokes. Additional filtering facilitated by capacitors generates a smooth and stable waveform, thereby ensuring optimal EMC.

[0087] Finally, the flexibility, safety, and compliance of the pillar-based energy storage system are emphasized. It provides insights into how this system can be adjusted to meet various applications and voltage requirements, thereby presenting a wide operating range. [Each feature section includes several items. These items are detailed below]

[0088] Item 1 - Cell. The cell utilized in this example is a cylindrical 33140 cell, which, in normal measurements, has a diameter of 33 mm and a length of 140 mm. Each cell is encapsulated with an insulating heat - shrink layer. This embodiment is designed for cells with a chemical composition of lithium iron phosphate (LiFePO4). LiFePO4 cells effectively become an open circuit when fully charged or over - charged, which is a state that generally interrupts the continuous current charging equilibrium seen in lead - acid batteries. This requires careful monitoring and balancing to ensure even charging across this type of cell. This model utilizes LiFePO4 cells, but other cell types with unique materials or alternative chemical compositions can also be used. These alternative cells, similar to lead - acid cells, may exhibit greater leakage when fully charged, thus reducing the need for individual cell balancing and monitoring. In this system, 24 cells are connected in series, each having a plateau voltage of 3.2 V, resulting in a nominal operating voltage of 72 V. When the cells are fully charged at 3.6 V, this embodiment can reach a maximum voltage of 86.4 V.

[0089] Item 2 - Balance and Monitoring (BMS) PCB. This PCB is slightly longer than the associated cells and features brass or phosphor bronze tabs (Item 18) on its top and bottom (left and right in Figure 5), enabling the measurement and balancing of voltages at the connections between cells. Each PCB monitors and balances the voltage at four points at each end of two associated cells. The BMS PCBs are electrically connected via flexible PCBs, enabling alignment with the PCB tubes for easy insertion without a rigid connection to adjacent connected BMS PCBs. The topmost PCB has male edge connectors and flanges (not shown) that align with injection-molded parts (Item 17), facilitating the pushing of the edge connectors into their mating parts when the cells are pushed under the injection-molded parts. The bottommost BMS PCB features flying leads to a fuse plate (Item 21) for the balance and monitoring of the joints of the bottom cells. The BMS is designed to operate at a mux voltage up to 100V with a design maximum differential voltage of 86.4V, which gives a lot of overhead space in this system.

[0090] Item 3 - Insulating Sheets. These are flexible rectangular sheets made of a durable, semi-rigid, flame-retardant insulating material such as PVC. They slide over the extension of the tubes (Item 6) and overlap with the PCB guides (Item 5). This overlap ensures that the creepage distance is suitable for the applied stepping voltage.

[0091] Item 4 - Screw Retaining Slots. These slots, formed in the extruded tube material, are equipped with flanges (not shown) that allow the PCB guides (Item 5) to be closed with a latch, thereby firmly holding the guides against the sides of the tube. These slots are designed to accommodate number 8 self-tapping screws.

[0092] Item 5 - PCB guiding part. This extrusion guiding part slides easily over the flange of the screw slot (Item 4) and provides a smooth surface for the BMS PCB to move smoothly. This guiding part is attached with a flange (shown) overlapping the insulating sheet (Item 3) and a holding segment (not shown) clipped onto the flange of the screw slot, holding the guiding part against the side of the tube.

[0093] Item 6 - Tubes. These tubes made of extruded aluminum have screw slots (Item 4) with flanges designed to fix the PCB guiding part (Item 5). These tubes are shaped to house cells and feature quarter - circle corners for four - cell tubes and half - circle corners for double - cell tubes.

[0094] Item 7 - Level switching. This feature, shown diagrammatically, indicates where the switching is performed. The purpose is to minimize the length of the copper loop through which current flows. In this example, the MOSFETs are placed back - to - back. This layout allows for a direct air flow to cool the MOSFETs in the virtual corridor. The fan drives air along this path when the system operates at high power levels or when the attached temperature sensor indicates the need for cooling.

[0095] Item 8 - Interconnection and balancing of cell packs. The oval symbols shown represent where the interconnections of the cell packs are located. These interconnections make maximum use of the use of copper while minimizing the path length and can extend across the full width of the four dual - tube cell packs. In Figure 2B, the interconnection spans left - right, while in Figure 4B, it spans the width of the tube. A typical flying capacitor device is utilized, and the size of the capacitor is selected to prevent significant imbalance due to overload of the associated MOSFET that switches the level of the flying capacitor. Further, it is large enough to balance the current required at the maximum switching frequency. To ensure the reliability of the substrate, film or ceramic capacitors are used. Inductors are installed in series to create a series - tuned circuit at the desired switching frequency. Using series inductors, the use of smaller capacitors and frequency shifting enables overload prevention and eliminates the need for another over - current protection. Series PTC (positive temperature coefficient resistor) is considered as a possible alternative protection mechanism.

[0096] Item 9 - Interconnection. In this example, two rows of standard header pins are used to interconnect to the associated PCB, a secondary substrate incorporating an inverter, or a compensator. Each connection features 40 male / female pins, ensuring a highly reliable multi - redundant interconnection.

[0097] Item 10 - Cell terminals. This design utilizes standard stainless - steel round - head coach bolts for these top cell terminals. The injection - molded cover, whose edge is shown in (Item 23), includes a recess. This recess locks in the square - positioning head of the bolt. A nut that is screwed in to fix the coach bolt in place is also included. After all 56 bolts are tightened, split washers or thin star washers can be added for improved electrical connection to the PCB (Item 15). The PCB is then placed on top of the bolts, after which additional washers (split washers or star washers) are applied and the PCB is fixed using additional nuts. M6 bolts and nuts are utilized in this example.

[0098] Item 11 - Spring Clip. These clips have a flange for holding the spring cover (Item 12), are screwed in, and clamp the bottom injection-molded cover to the aluminum tube. The screw holding the clip is driven into the screw slot of the tube (Item 4). These spring clips allow the spring cover (Item 12) to slide over them. The flange then pops out and locks against the side of the recess of the spring cover, preventing the spring cover from being removed without a suitable tool.

[0099] Item 12 - Spring Cover. Made of thin (in this case 0.6 mm) stainless steel, the edge of this spring cover is bent upward to fix the plastic molded part that positions the spring. The middle of the cover is embossed downward at the center to prevent the cover from deforming by the spring force holding the cover.

[0100] Item 13 - Reserved.

[0101] Item 14 - BMS Edge Connector. The Battery Management System (BMS) is controlled by four lines detailed in Figure 8. These lines are: · Enable: Open circuit or 0V = no active channel of BMS; positive voltage of battery = all BMS channels are active. · MuxOn: Toggle switch to 10~0V = switch muxOFF; toggle switch to 0~10V = switch muxON. · MuxA: The first Mux channel (mux is connected to the +ve of odd cells). · MuxB: The second Mux channel (mux is connected to the +ve of even cells).

[0102] The edge connector has six pins. MuxA and MuxB are each connected through two pins of the edge connector for reliability and to sense the battery voltage and carry the balanced current as described in the explanation of Figure 8.

[0103] Item 15 - High - level BMS. As shown in FIGS. 6 and 7, this substrate, designed to manage the ends of all 28 strings of cells, features a gold - plated finish connection for reliable and non - corrosive connectivity to the coach bolts. Its two main functions are: · As shown in FIG. 6, the substrate enables a high level of balance in the bank of cell strings by adjusting the forward or reverse switching timing. · According to FIG. 7, it uses the flying capacitor topology to enable a high level of balance in the bank of cell strings.

[0104] This substrate design incorporates two mid - output (0.5 A) switching regulators, and their voltages can be changed from 0 V to the positive battery voltage.

[0105] This high - level BMS, also known as the optimizer substrate (Item 15), interacts with the string BMS (Item 2) and measures and corrects the voltage or charge level of specific cells through several steps: · Operation of the Mux system: Assuming the Mux system is not yet enabled, it is operated by setting "Enable" to the positive voltage of the battery. · Change of MuxOn: This board toggles "MuxOn" to the low state (0 V). · Tube Mux selection: This substrate enables the mux to select one of four dual - tubes by activating the gate of the corresponding MOSFET attached to the optimizer substrate, and it electrically connects the regulator to the selected tube (not shown). · Adjustment of the regulator: The two switching regulators are set to approximately the voltages of two cells. These are generally set to the predicted voltages at the positive terminals of adjacent even and odd cells. · Configuration of the regulator: The switching regulator is configured to put its MOSFET into a non-operating state, i.e., a high-impedance state, enabling the regulator capacitor to maintain the set voltage. · Change of MuxOn: This board toggles "MuxOn" up to the high state (10V). · Connection of cells: The cell with the voltage closest to the set voltage is connected as per the guidelines described in Figure 8. · Mux voltage measurement and charge adjustment: Each mux voltage is measured. Abnormal or unexpected voltages are recorded and later reported when evaluating which cells may require early charging. Next, the switching regulator is enabled and adjusted to a voltage suitable for charging or discharging the connected cells. The voltage is measured when the regulator is enabled, and the measurement steps obtained at the voltage are used to estimate the current flowing into or out of the selected cells. · Repetition: The entire sequence is repeated for other cells.

[0106] This detailed and orderly process enables the high-level BMS board to cooperate with the optimizer board to provide efficient and effective management of the battery system.

[0107] Item 16 - Reserved.

[0108] Item 17 - BMS pusher. This molded part is associated with the Battery Management System (BMS) board. It ensures that the BMS is pushed into the tube by the cell and fully drives the BMS into its connector when the cell is fully set against the relevant coach bolt.

[0109] Item 18 - Tabs of the cells. These tabs protrude above and below the BMS PCB and connect between the cells as shown horizontally in Figure 5. The surfaces of these tabs that fit into the cells are dimpled to a height of 0.2 mm in this case. This dimpling ensures that any corrosion does not result in the separation of the mating surfaces. For optimal reliability, silicone grease is applied to the surface and the dimples assist in holding the grease via capillary action.

[0110] Item 19 - Terminals. These terminals, which are attached to the end plate PCB, may have a design similar to the flange described in (Item 18). Alternatively, they can be slightly bulged to achieve equivalent results.

[0111] Item 20 - Fuses. This is a standard surface - mounted fuse. For any design, low - voltage (<100V dc ) fuses are utilized. In the design of Figure 7, these fuses have a higher rated current than the inverter input fuses. Since the inverter input fuses have a higher rated voltage, they blow first.

[0112] Item 21 - End plate PCB. This connects across the ends in each string of 12 cells and includes flying leads for the BMS PCB to connect to. This PCB applies a large force in the range of 4 - 20 kg to each string of cells, ensuring a reliable long - term electrical connection.

[0113] Item 22 - Springs for cell strings. These strong springs are mounted in pairs for each dual - tube. When fully compressed, they apply a force greater than 10 kg, thereby maintaining all the cells in a firmly pressed configuration within the string for optimal performance.

[0114] Item 23 - Injection - molded top cover (its lower edge). This identifies the position of the lower edge of the injection - molded cover, which is tasked with firmly holding all the cell tubes in place, ensuring structural stability and integrity.

[0115] Item 24 - Wiring from the bottom BMS PCB to the end - plate PCB. This wiring facilitates the connection between the bottom BMS PCB (Item 2) and the end - plate PCB (Item 21). It is designed to be long and robust, enabling the removal of the end - plate PCB when necessary for cell polarity and charge verification. Verification is performed using a dedicated test piece or a multimeter. This wiring has sufficient strength to serve as a pull - string for pulling cells out of the tubes when needed.

[0116] Item 25 - Control - signal capacitor / resistor. This component couples the control signals and manages the corresponding multiplexer (mux). The rating of this capacitor enables the capacitor to block the control - signal voltage from the mux or cell voltage when exceeding the string voltage. It has sufficient capacitance to hold the leakage charge in the mux's MOSFET for the duration of the sampling period, which is usually sufficient at 1 ms. The resistor within this setup limits the current into the unsaturated transistor and the Zener voltage limiter (Item 27), preventing the mux's MOSFET from being forced ON or controlling the overload of the driver when operating multiple BMS PCBs.

[0117] Item 26 - Transistors with emitter - coupled. These transistors are coupled to the joined source of the mux's MOSFET, and their collectors are connected to the gate of the same MOSFET. Their purpose is to turn off the MOSFET when it is unsaturated. The voltage level at which unsaturation occurs is set by a resistor divider that spans from the drain of the MOSFET to the base of the transistors that detect these unsaturations.

[0118] Item 27 - Zener voltage limiter. This component is composed of two transistors wired across the source / gate of a MOSFET and functions as a Zener to limit the gate voltage. The two transistors are connected in series, and the maximum voltage to the MOSFET gate is determined by the breakdown of the reverse emitter junctions in series. Transistors are ideal for this role because they have a very sharp knee voltage that is the result of reverse breakdown at the emitter-base junction.

[0119] Item 28 - Active input regulator. This set of components facilitates enabling a multiplexer (mux) or shutting it down to a low-power state. This device includes three basic parts, namely a high-value resistor, a connected diode, and a second diode. The high-value resistor serves to energize the connected diode when the mux is enabled. The role of the second diode is to pull down the gate of the MOSFET and turn off all MOSFETs when the enable input is pulled low.

[0120] Item 29 - Pull-down resistor. This resistor plays an important role in ensuring that the MOSFET remains in the "OFF" state when not actively controlled. It is achieved by creating a current path that ensures the voltage across the MOSFET gate remains low, preventing them from turning on when the active input floats.

[0121] Item 30 - External common-mode choke. This component is used to further reduce emissions optionally implemented in the system. The common-mode choke is a type of electrical filter that helps block interference and noise on the line. In this case, the choke is an additional layer of noise reduction, ensuring minimal interference.

[0122] Item 31 - Common connection point. This serves as a junction for functional grounding or shield common point. It is an important component that ensures maintaining EMI at a minimum while providing system grounding and contributing to the overall safety, compliance, and functionality of the system.

[0123] Item 32 - Filtering component. This component filters the compensation step. In particular, it includes a snubber. This snubber, which is composed of a capacitor and a resistor, suppresses or "snubs" any ringing noise resulting from repeated minor timing step failures. It has been found that the ideal capacitor ranges from 0.1 to 0.5 times the value of the line capacitor installed across the choke. The optimal resistor has been found to be a 5W resistor in the range of 10 - 50Ω when using a 0.47μF snubbing capacitor.

[0124] Item 33 - Shielding part. This shielding part, which has three main components, is used to protect the system and reduce interference. It includes a top shielding part (shown schematically as Item 35) that surrounds the PCB and is electrically screwed into an aluminum tube, the aluminum tube (Item 34), and the spring cover (Item 12). The spring clip (Item 11) electrically connects these components.

[0125] Item 34 - Aluminum tube. These tubes house the cells and provide shielding and protection against any potential overheating events that could damage the outside of the pillar.

[0126] Item 35 - Top shielding part. This is the part of the top shield that is screwed into the aluminum tube. It is an important component that provides additional protection and stability to the system.

[0127] Item 36 - Double rib. This rib is designed to fit with a (Item 44) i.e., a closed cell or silicone seal located at the base. This double rib can additionally receive a bead of silicone grease, creating an IP67 waterproof seal or relying on it as a base seal for IP65 - IP66 seals.

[0128] Item 37 - Cell insulation opening. It is an opening through which cells can be set and removed.

[0129] Item 38 - Mounting hole. This is a hole in the base injection - molded for a spring clip and a number 8 self - tapper, fixing the clip (Item 11) and the base (Figure 10) to the tube (Item 6).

[0130] Item 39 - Spring clip compression part. This item shows how the spring clip (Item 11) is compressed to remove or set the spring cover (Item 12).

[0131] Item 40 - Base plate. Also injection - molded, this base plate features horizontal holes on three sides for stainless - steel pins to slide into, enabling a hinge action for cell replacement. These pins are set on both sides, fixing a pillar or any of the three sides, allowing it to lie horizontally in the left, front, or right direction.

[0132] Item 41 - Screw holes for fixing the base. These are screw holes for fixing the base. The lower side has a cross - hatch pattern and is firmly placed in gap - filling materials such as wet cement, liquid nails, or epoxy resin. The filling material ensures that the base sits firmly and is stabilized by the gap - filling material alone.

[0133] Item 42 - Stainless steel pins. These pins slide along the length of one or two sides of the pillar. The injection-molded cover at the bottom has a strong flange with holes that accept these pins and are suitable for lifting the weight of the cell and pillar without significantly deforming the base plate (Item 40) or the injection-molded cover at the bottom.

[0134] Item 43 - Spring cover assembly. The figure clarifies two spring covers and, more generally, the injection-molded cover assembly at the bottom.

[0135] Item 44 - Sealing recess. A recess for a foam or silicone seal of a closed cell that fits into the double rib (Item 36). This seal is designed to create a watertight housing when paired with the rib.

[0136] Item 45 - Insulation reinforced with extruded polycarbonate. This insulation is used to cover the aluminum tube and provides protection and additional strength. This insulation is shaped with recesses and is similar to the insulation of the roof panel to improve durability. It is produced as four corners and joining pieces in the middle of each side. The injection-molded cover at the bottom has a deep recess where the insulation sheet sits. This insulation fits together and self-seals and self-clamps by an interlocking device (not shown) when extended to cover the tube. For improved IP protection, the bottom is sealed with a continuous foam material installed in the recess before extrusion. In another embodiment, the base is filled with a sealing adhesive before the insulation is slid into place. The outer flange of the recess is lower than the inner side to prevent water from entering the housing.

Claims

1. An energy storage system, Comprising a plurality of elongated compartments, each designed to accommodate a string of energy storage cells, Each compartment is equipped with an accessible opening, which is designed to facilitate the easy installation and removal of the storage cells, The compartments house two or more storage cells, positioned adjacent to each other within their tips, A holding mechanism is also incorporated, which functions to form a reliable current path by firmly pressing and holding the string of cells together, The system incorporates a balancing mechanism, The mechanism includes a balancing system with electrical tabs connecting the junctions of adjacent cells, and a mechanism for moving charge in and out of the tabs, The movement of charge facilitates the charging or discharging of the cells, thereby maintaining a balanced voltage across the system.

2. The balancing mechanism is equipped with a sensing unit that actively measures the voltage levels of the storage cells via a multiplexer device, and the system is also characterized by a programmable voltage regulator that interacts with the cells via the multiplexer device. The sensing unit, the voltage regulator, and the multiplexer device operate simultaneously to balance the measured or calculated voltage across the string of energy storage cells housed within each elongated compartment. The system according to claim 1.

3. The parallel mechanism of the system according to claim 1 utilizes a flying capacitor mechanism.

4. The plurality of elongated compartments are formed from aluminum tubes, which incorporate a holding mechanism for a printed circuit board (PCB), and the PCB is positioned between two or more cells. The system according to any one of claims 1 to 3.

5. A second insulating layer is applied between the cells and the aluminum, and the holding mechanism is made of an insulating material that extends beyond the insulating portion positioned between the cells and the aluminum, thereby providing an appropriate creepage distance to ensure a safe operation of applying voltage to the system. The system according to claim 4.

6. The system according to any one of claims 1 to 5, creating a system with a reinforced insulation part that shields an external metal surface using an additional insulating layer, thereby protecting personnel from potentially dangerous voltages.

7. The system according to claim 6, wherein the additional insulating layer is composed of an interlocking extruded plastic corrugated material.

8. The system according to claim 6, wherein the additional insulating layer comprises one or more layers of packaging material, and the packaging material is either a shrinkable material or a vinyl packaging material.

9. The system according to any one of claims 1 to 8, wherein the string of energy storage cells are welded together before insulation.

10. The system according to any one of claims 1 to 9, wherein the tabs of the balancing mechanism incorporate spring pins and contact the electrical sensing terminals of the cells.

11. The system according to any one of claims 1 to 10, wherein the elongated section is vertically mounted on a base plate, and the base plate is separable from the elongated section via a hinge or a pin, thereby assisting in facilitating the setting and removal of the cell string.

12. The system according to any one of claims 1 to 11, wherein the cell string is fixed in place by a cell string spring, and the cell string spring is further held in place by a spring cover.

13. The system according to claim 12, wherein the spring cover is held by a spring clip and can be released by compressing the tab of the spring clip using a tool.

14. The system according to claim 12, wherein the spring cover is fixed in place by a rotary catch or a latch mechanism.

15. The system according to any one of claims 1 to 14, wherein an AC voltage suitable for connection to a power source is supplied by a connected inverter.

16. The system according to any one of claims 1 to 14, wherein an AC voltage suitable for connection to a power system is generated by a stepped cell string that generates a stepped sine wave approximation waveform, and a compensator connected in series that smooths the voltage steps, thereby creating the AC voltage.

17. The system according to claim 16, wherein the compensator is an active device that creates a waveform corresponding to the difference between the stepped AC waveform and a desired AC waveform suitable for connection to the power system.

18. The system according to claim 16, wherein the compensator comprises an inductor that feeds power to a filter capacitor.

19. The system according to any one of claims 1 to 18, characterized by a pillar that generates an AC voltage.

20. The system according to claim 19, wherein the pillars are connected in series in a loop, and the charge balance in the storage cell is maintained by small-scale voltage regulation, resulting in a flow of unbalanced current that preferentially charges or discharges the pillars one after another.

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