Battery energy storage system

Abstract

The present invention is an energy storage system comprising: a plurality of elongate compartments, each designed to accommodate a string of energy storage cells; each compartment is provided with an accessible opening, and the design is used for facilitating the installation and disassembly of the energy storage battery cell; the compartment is designed to accommodate two or more energy storage cells, and the energy storage cells are adjacently arranged at the tail ends of the energy storage cells; the battery further comprises a retaining structure which is used for firmly pressing the battery cell strings together so as to form a reliable current path; the system comprises a balance mechanism; the structure includes a balancing system including electrical tabs connecting junctions of adjacent cells and a structure capable of moving charge into and out of the tabs. This charge movement facilitates the charging or discharging of the cells, thereby maintaining the voltage balance of the entire system.

Description

Technical Field

[0001] The present invention relates to the field of energy storage systems, with a particular focus on developing an efficient, economical and usable solution that can be adapted for a variety of applications from residential to grid-scale energy storage. Background Art

[0002] The growing urgency to mitigate climate change has driven the rapid development of renewable energy technologies. These technologies, such as solar and wind, offer a promising future with abundant, cost-effective energy with minimal impact on the environment. Despite this potential, renewable energy sources face significant limitations in terms of intermittency – they only produce energy when the sun shines or the wind blows, not necessarily when the energy is needed. To realize their full potential and transition away from an energy system based on fossil fuels, efficient and cost-effective energy storage solutions are needed.

[0003] Energy storage systems offer a way to match generation from renewable energy sources with demand. They store excess energy produced during periods of high generation and low demand, releasing it back into the grid when demand exceeds generation. They therefore offer the possibility of fully exploiting renewable energy sources, helping to reduce dependence on fossil fuels and significantly lowering greenhouse gas emissions.

[0004] Over the years, many energy storage systems have been developed, from pumped hydro to battery technologies such as lead acid, lithium-ion, and newer technologies such as solid-state batteries and flow batteries. However, these solutions often come with a host of challenges. For example, pumped hydro, while effective, requires large spaces and specific geographical features, making it unsuitable for most applications. On the other hand, battery technologies can be costly, have varying degrees of energy density, and often require complex battery management systems (BMS) to ensure safe and efficient operation. The lifespan and maintenance of these systems also present considerable challenges, resulting in high capital costs and electronic waste.

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

[0006] Current solutions often require unique product designs for each application area, making them expensive and difficult to maintain. For example, a residential solar / battery system often requires a hybrid inverter that combines the functionality of a solar inverter and a battery inverter. Additionally, each grid-scale application requires a custom design due to its specific energy requirements and installation environment. These challenges complicate the creation of cost-effective energy storage solutions that can be easily deployed and serviced.

[0007] Despite the progress made in this regard, existing technologies and solutions do not adequately address these challenges, posing a significant barrier to the widespread adoption of renewable energy. Therefore, there is an urgent need for an energy storage solution that is economical, efficient, durable, easy to maintain, and suitable for a variety of application areas. The present invention aims to address these shortcomings and provide such a solution. Summary of the invention

[0008] Referring to the accompanying drawings, there is shown an energy storage system that can be connected to a main grid (grid-connected) or used independently of the main grid (off-grid).

[0009] The present invention expands upon the concepts proposed in the prior patents, including 1. WO2015184512A1 “Power conversion method and system”, 2. WO2015184511A1 “System and method for detecting connector faults in a power conversion system”, 3. W02016008003A1 “Method for controlling a power conversion system”, and 4. WO2019113647A1 “Battery Pack” These aforementioned patents are incorporated herein by reference. The present invention introduces multiple layers of additional functionality and utility that enhance the prior patents in significant ways: 1. The energy storage system proposed herein has a high capacity design with improved electromagnetic interference (EMI) and electromagnetic compatibility (EMC) compliance. It also provides simplified cell replacement and installation compared to previously described battery packs. These improvements are achieved through the features outlined in the claims and the following description.

[0010] 2. The present invention proposes a system with series and parallel connections, providing enhanced redundancy and commercial and utility energy storage options. The details of the design are detailed in the subsequent claims and description.

[0011] 3. This energy storage system also provides improved surge protection and testing capabilities compared to previous systems. The specific details of these enhancements are outlined in the claims and description that will be presented shortly. Our initial invention point is the energy storage system, which is the key to this invention. The system includes 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 specifically designed to facilitate the installation and removal of these energy storage cells.

[0012] These compartments are structured to accommodate two or more energy storage cells arranged adjacent to each other within their confines. In addition, the system contains a retaining structure that firmly presses the string of cells together. This setup ensures a reliable current path, forming the backbone of our energy storage systems.

[0013] In addition, the system integrates a complex balancing mechanism. The mechanism has a balancing system that includes electrical tabs that connect adjacent cells at their junctions. The mechanism also has a means to move charge in or out of these electrical tabs. This allows the cells to charge or discharge, thereby harmonizing their voltages. This complex and efficient process enables long strings of cells to be balanced without the need for complex wiring.

[0014] Subsequent sections will further describe detailed aspects of the present invention, as well as specific details of its operation, installation and benefits.

[0015] Features are added according to the following system description, which describes the best-known embodiments as non-limiting examples: Figure 1 : Top view of extruded aluminum tubes used in energy storage batteries Figure 1 Provides an aerial view of an extruded aluminum tube designed specifically to house battery cell storage. The layout and functionality demonstrated in this image provide insights into how this setup supports efficient and safe battery cell system operation.

[0016] Figure 1 Key elements: •Battery cells and PCB: The tube is designed to hold two battery cells side by side (item 1). The cells are separated by a printed circuit board (PCB) (item 2) that is responsible for the electrical balancing of the battery system.

[0017] • Extrusion Screw Holes: The design incorporates extrusion screw holes (item 4) to allow for a secure connection to the molded cap. These screw holes are integral to maintaining structural integrity and ensuring a rigid fit.

[0018] • Insulation: A notable feature of the tube design is the provision of a second layer of double insulation between the cell and the tube (item 3). This extra safety measure provides a solid barrier that reduces the risk of electrical interference or electric shock. The extra layer of insulation also protects against corrosion and damage from poor cell quality or shrink film.

[0019] •PCB Clamps: The layout also includes PCB clamps, strategically positioned to provide support to the PCB while enhancing insulation. These clamps not only hold the PCB in place but also ensure its security.

[0020] • Overlap insulation: First, install overlapping insulation (items 3 and 5) to further improve safety standards. This layer is particularly important in maintaining creepage distance, which is the shortest path between two conductive parts or between a conductive part and the bounding surface of the equipment, measured along the insulating surface.

[0021] Figure 1 The layout shown provides a comprehensive overview of the complex design of the extruded aluminum tubes, demonstrating the careful thought behind their design, particularly in ensuring the safety and practicality of battery storage systems.

[0022] Figure 2A : AC battery storage grid perspective Figure 2A An off-axis, top-down perspective view of the organized grid structure is provided, showing the efficient use of extruded aluminum tubes. The image shows a 4x7 grid arrangement housing 28 tubes and is paired with a schematic detailing the electrical arrangement for generating the stepped AC voltage. Figure 6 ) to align.

[0023] Figure 2A Key elements: • Stepping between battery packs: (Item 7) refers to the switch position that produces the step voltage, marking the transition from stored DC to usable AC output. It can be seen that the stepping is arranged horizontally with the battery pack. With the left side (Item 9) set to 0V, the series cells in the tube are each 72V, and the output voltage on the right side (Item 9) ranges from -504V to +504V.

[0024] • Interconnection of the compensator (Item 9): This feature shows the interconnection location of the compensator located on the subsequent PCB. The compensator is an important component that converts the stepped AC power into a sine wave suitable for use, and works with the stepped mechanism to regulate and modulate the voltage level, thereby ensuring compatibility of the power system.

[0025] • Dimensions and construction: The system, including injection molded end caps, is approximately 1900 mm high, 300 mm wide and 300 mm deep. The figure shows the extruded aluminum tube (item 6) that can accommodate the battery cells of the complete AC system and their associated PCB.

[0026] Figure 2B : DC battery storage grid perspective and Figure 2A parallel, Figure 2B With DC electrical configuration ( Figure 7 ) show the same grid arrangement of battery storage compartments, but a high-voltage (HV) system designed to generate DC voltage for use by the inverter.

[0027] Figure 2B Key elements: • Interconnections between battery packs (Item 8): This figure shows the electrical location on the PCB of the interconnections between the battery packs and the flying capacitors used for balancing. This also shows the interconnections lateral to the parallel battery pack layout.

[0028] • DC output layout of the inverter: (Item 9) indicates the interconnection location with the inverter on the subsequent PCB. The inverter plays a vital role in converting the high voltage DC output into AC power.

[0029] • Size and structure: Figure 2A Consistent, Figure 2B The same compact size and layout is shown. An extruded aluminum tube (Item 6) is also shown, showing the storage capacity of the system and its well-constructed design.

[0030] In general, Figure 2A and 2B A comprehensive overview of the various electrical configurations possible for this battery storage system is provided, highlighting its flexibility in power output and system design, as well as possible I / O arrangements.

[0031] Figure 3 : Alternative tube configuration for four-cell storage Figure 3 Introduced Figure 1 An alternative to the arrangement outlined in , showing a tube with a more square structure and rounded corners to house the cells. Figure 1 Unlike the dual-cell housing in the , this tube is designed to hold four cells. Figure 3 Key elements: • Four-cell housing: This configuration houses four layers of cells in a tube. Figure 1 Compared to the two-layer cell layout, the storage capacity is effectively doubled. This design simplifies the redundancy mechanism, from the software-driven process ( Figure 2A The 4x dual tubes are shown vertically in the figure) to achieve redundancy through four parallel cells fused to the balance PCB.

[0032] • Fewer balancing components: The same orientation of the four cells facilitates parallel connection of each layer, significantly reducing the number of balancing components required. This configuration—four parallel cells and twelve series cells (24 cells total, considering the loop)—produces a nominal voltage similar to Figure 1 voltage, but provides enhanced redundancy and reduces the number of balancing components by almost a quarter.

[0033] • Risk management: Despite enhanced storage capacity and redundancy, this configuration introduces potential risks such as excessive current or arc flash due to parallel cells at each layer. Fuses can reduce the risk of a complete short circuit.

[0034] • Fuse links: Cell connection points are equipped with fusible links leading to the BMS PCB. Since the fusible links can only carry balancing currents, the resistance of the fusible links is relatively high without significantly reducing efficiency. Unlike through-current fuses, which require minimum resistance for efficient operation and heat dissipation, these links only encounter relatively high currents during abnormal events. Therefore, their higher resistance levels and lower current capacity are appropriate, contributing to overall system safety and reliability.

[0035] •and Figure 1 In addition to the above changes, Figure 3 The layout and components in Figure 1 The same as shown in .

[0036] In introducing this alternative configuration, Figure 3 A design that simplifies energy storage replacement, enhances redundancy, reduces the number of balancing components, and effectively manages associated risks is highlighted. This flexible design avoids reliance on a specific power conversion method, allowing for adaptive system configuration based on specific needs.

[0037] Figure 4A : Four-cell AC battery energy storage grid perspective Figure 4A and Figure 2A Again, an off-axis, top-down perspective of the grid layout is provided. However, this diagram uses a modified tube design specifically designed to accommodate four battery cells, consistent with the schematic for generating a stepped AC voltage ( Figure 6 ).

[0038] Figure 4A Key elements: • AC output arrangement: The switch positions that create the step voltage are labeled (item 7). This highlights the conversion process from the DC power stored within the four cells to the usable AC output. With this arrangement, the storage density is slightly increased, enabling an additional switch layer that can achieve a -576V to +576V step at the terminals (item 9) at 72V per two cells.

[0039] • Interconnection of the compensator (item 9): This figure shows the interconnection location of the compensator on the next PCB. The compensator is a key component that converts the stepped AC into a sine wave suitable for use, coordinates with the stepped device to manage and adjust the voltage level, and ensures the compatibility of the power system. The compensator can be an active device mentioned in the relevant patent or a passive inductor that forms PWM as needed to produce the required quality sine wave.

[0040] • Size and structure: e.g. Figure 2AAs shown, the dimensions of the system, including injection molded end caps, are approximately 1900 mm high, 300 mm wide, and 300 mm deep. Despite the increased storage capacity of the quad-cell, the system remains compact. The figure also depicts the modified aluminum tube (item 6) that can accommodate the quad-cell and its corresponding PCB.

[0041] • Storage capacity: This arrangement can store approximately 14% more in the same volume.

[0042] Figure 4B : Four-cell DC battery energy storage grid perspective Figure 4B Aligned with DC electrical configuration, Figure 2B It shows the grid arrangement of the four-cell storage compartment, indicating a system designed to generate DC voltage for the inverter.

[0043] Figure 4B Key elements: • Inverter Interconnects (Item 8): This feature demonstrates the electrical locations on the PCB of the interconnects between the cell groups and the locations of the flying capacitors used for balancing.

[0044] • DC output layout: (Item 9) refers to the interconnection to the inverter on the subsequent PCB. The inverter is critical in converting the high-voltage DC output of the four-cell configuration to AC.

[0045] • Size and structure: e.g. Figure 4A As shown, Figure 4B The same compact size and layout are shown, along with a modified aluminum tube that can accommodate a four-cell configuration (Item 6).

[0046] • Storage capacity: This arrangement can store approximately 14% more in the same volume.

[0047] Figure 4A and 4B Together, they provide a comprehensive overview of different possible electrical arrangements for such a four-cell energy storage system. They show the potential for enhanced voltage output, storage capacity, and system design flexibility, while indicating possible terminal polarities.

[0048] Figure 5 : Side view of a twin-tube configuration Figure 5 A side view of a dual tube configuration used in a battery storage system is provided. On top of this configuration, there is an injection molded cover that attaches to all 28 tubes. The cover itself is not shown in this image, but its bottom edge is marked (Item 23).

[0049] Figure 5 Key elements: • Coach bolts and PCB: Coach bolts (item 10) are bolted to the cover as shown. These bolts are held in place by corresponding nuts and hold the printed circuit board (PCB, (item 15)) by star or split washers which are further clamped by a second set of associated nuts.

[0050] • Cells and Connectors: This figure depicts the cell (item 1) and the card edge connector (item 14) that holds the balancing and monitoring board (item 2). The balancing and monitoring board is securely pressed into the edge connector by an injection molded pressure plate (item 17). The pressure plate is pushed by the top cell, which in turn pushes the PCB into the connector.

[0051] • Balancing and Monitoring Board (BMS): The Balancing and Monitoring Board (Item 2) consists of multiple sections, each with phosphor bronze terminals for electrical connection to the connection points between cells. Each segment is responsible for monitoring and balancing each end of the adjacent cells. In addition, a flexible connector spans across subsequent cells before connecting to the next BMS segment.

[0052] • Spring loaded insert and fuse plate: Located at the end of the tube is a spring loaded insert. This insert (not shown) is made of injection molded material and has a PCB fuse plate (item 21) that connects to the ends of the cell. A schematic diagram of the spring is shown in (item 22), the terminals are shown in (item 19) and the fuse is shown in (item 20). The fuse can be installed after the cell is installed and tested to ensure polarity. The fuse makes an electrical connection between the two ends of the cell and protects the cell from overcurrent that may result from system damage or failure.

[0053] Figure 5 The dual-pipe configuration is fully illustrated, detailing the key components and their location in the system. It aids in understanding the electrical connections, mechanical setup, and the role of each component in the overall system.

[0054] Figure 6 : Schematic diagram of PCB layout for step-by-step sine wave approximation Figure 6 A schematic diagram of a PCB layout is shown, specifically designed to generate a step-by-step approximation of a sinusoidal waveform. The device primarily uses an N-channel MOSFET (Metal Oxide Semiconductor Field Effect Transistor) with its drain connected to the positive connections of four dual-tube cells, such as Figure 1 and 2A As shown in the figure, it is shown using the standard battery symbol with a short positive segment at the top.

[0055] Figure 6 Key elements: • Copper protection: The PCB contains enough copper to ensure that a cell short circuit event will trigger the fuse (e.g. Figure 5as shown), and then any damage to the board itself due to the current in the positive and negative vertical schematic lines.

[0056] • Driver reference voltage: The drivers of all connected MOSFETs, including those used for in-cell balancing, are referenced to their own supply to prevent unwanted switching caused by 0 V current. The sources of the MOSFETs are connected to the negative terminal of the cell string, while their drivers are connected to 0 V of the associated microprocessor supply.

[0057] • Parallel Switching MOSFETs: This schematic includes multiple 100 V switching MOSFETs connected and driven in parallel. This configuration reduces switch resistance and reduces overall losses. This arrangement improves reliability by eliminating the need for external wiring because all interconnect paths are incorporated into the PCB.

[0058] • BMS PCB string connectors: The PCB has 28 connectors for the battery management system (BMS) PCB strings. Each string corresponds to a double tube, such as Figure 2A In contrast, if the design follows Figure 4A , the wiring will be different and there will be 16 connectors instead.

[0059] Not shown in the diagram, the PCB communicates with the system's control compensator and makes adjustments under its control to produce an approximation of the power waveform. This device is called an "optimizer" because of its dual function: • The optimizer controls the storage cells, switching them to produce an approximation with very high power conversion efficiency. The slow switching frequency results in only nominal power losses, while the combined series resistance of all MOSFETs, in this case four of the 3.5mΩ devices in parallel, is less than 2mΩ per switching H-bridge. This results in less than 14mΩ for all seven optimized cells. Therefore, at 20A and 240V rms The losses are less than 0.1% at this level. This extremely high efficiency results in correspondingly low heat dissipation and the ability to operate passively cooled. A small recirculation fan is mounted within the cavity that houses the optimizer and compensator plates. This fan operates at high power levels, avoiding the need for vents in this case.

[0060] •The compensator controls the switching times, keeping the series-connected cell group at a higher charge level for longer during discharge and vice versa.

[0061] In conclusion, Figure 6 A comprehensive schematic of the PCB design and interconnections is provided. It highlights how the PCB, MOSFETs, and other components collaborate to form a step-by-step approximation of a sinusoidal waveform, demonstrating effective design choices for managing current flow and minimizing losses, making it an ideal component of an energy storage system.

[0062] Figure 7 : Schematic diagram of high voltage DC PCB layout for inverter Figure 7 Figure 1 is a schematic diagram of a PCB layout for balancing a series string of cells using a topology commonly known as a flying capacitor balancer. This configuration produces high voltage DC for use by the inverter. In this design, an N-channel MOSFET is used with its drain connected to four dual-tube cells, connected to the Figure 1 and 2B The style is consistent with .

[0063] Figure 7 Key elements: • Copper protection: The PCB has enough copper to ensure that if the cell shorts, the fuse (such as Figure 5 ) will fuse before the circuit board is damaged by current flowing through the positive and negative vertical wires.

[0064] • Driver reference voltage: The drivers of all connected MOSFETs, including those used for in-cell balancing, are referenced to their own supply to prevent unwanted switching caused by 0 V current. The sources of the MOSFETs are connected to the negative terminal of the cell string, while their drivers are connected to 0 V of the associated microprocessor supply.

[0065] • Cell strings and balancing capacitors: The cell strings are connected in series and the electrolytic capacitors used for balancing are connected as shown in (Item 8). A positive temperature coefficient (PTC) thermal fuse is placed in series with the capacitor to limit the current. An inductor tuned to the switching frequency can be placed in series with the capacitor, allowing the use of smaller capacitors of lower value, so film or ceramic capacitors can be selected.

[0066] • Voltage Monitoring: String voltage monitoring is provided to adjust the switching frequency based on the voltage difference across the string to limit the average current. In a non-tuned system, the power through the flying capacitor is proportional to the switching frequency, so the flying capacitor switching period is proportional to the voltage difference between the highest and lowest measured string voltages. If an inductor is used, the frequency varies according to a calculation formula that takes into account the Q factor of the resonant circuit.

[0067] • BMS PCB string connectors: The PCB has 28 connectors for the Battery Management System (BMS) PCB strings, one string per double tube, with Figure 2B If you follow Figure 4B The layout, wiring will be different, with 16 connectors instead.

[0068] •No external wiring: All interconnection paths pass through the PCB, requiring no external wiring.

[0069] Overall, Figure 7A clear depiction of the PCB arrangement for generating high voltage DC for inverter use. This arrangement effectively manages cell balancing, current limiting, and voltage monitoring. It shows how efficient design choices can simplify construction and operation while improving system safety and reliability.

[0070] Figure 8 : Schematic diagram of the switching mechanism that connects the battery cells to the multiplexer channels Figure 8 Depicted is a schematic detailing the switching mechanism used to connect cell terminals to multiplexer (mux) channels. The figure reveals the complex interaction of various components that create a low-tech four-wire control mechanism that implements an efficient, overload-protected switching mechanism to support replaceable cells on large-scale energy storage systems. Not depicted are the switching regulators that drive the MuxChA and MuxChB channels and the precision ADCs that monitor the voltages on these lines. Selecting a multiplexer channel and connecting it to a cell connection point involves driving the associated regulator to a voltage close to the expected cell voltage and then connecting to the nearest cell multiplexer on command.

[0071] Figure 8 Key elements: • Resistor-capacitor pair (Item 25): This pair consists of a resistor to limit current and a capacitor to block the voltage difference between the drivers that switch the state of the multiplexer MOSFETs (metal oxide semiconductor field effect transistors). The drivers alternate between high and low states, turning the selected multiplexer on or off, respectively.

[0072] • Desaturation NPN transistors (item 26): These transistors are designed to prevent the multiplexer from turning on when the voltage of the cells to which they are connected is not within the common multiplexer potential, and to disable the MOSFETs when the difference between the cell voltage and the multiplexer channel voltage exceeds the voltage set by the desaturation sense resistors connected to the bases of these transistors. This feature allows initial connection to the nearest cell and prevents potential damage from voltage spikes or excessive multiplexer current. This desaturation mechanism ensures that any connection is bistable; the cell closer to the multiplexer potential will turn on more forcefully, pulling the multiplexer voltage away from the other cell voltage, causing the latter to desaturate and turn off further.

[0073] • Series reverse emitter-base junction (Item 27): These transistors exhibit a steep knee current at about 5 V and very low leakage due to their series reverse emitter-base junction, which is not possible with standard Zener diodes at voltages close to their turn-on point. This feature enables the multiplexer to remain on for a long time before needing to be turned off and on again, thereby recharging the DC blocking capacitors (Item 25).

[0074] • Dual Channel: The diagram has two copies of the circuit, shown as top and bottom, connected to the even and odd cell positive terminals respectively (odd and even negative terminals of the series cells). This design serves a dual purpose: — The multiplexer channels are separated by at least 5 V (minimum charge of two cells is 2.5 V), and a desaturation voltage of 2.5 V is easily achieved using a base resistor divider.

[0075] —A single cell can be charged or discharged, with one multiplexer channel connected to its positive terminal and another to its negative terminal.

[0076] • Shutdown Mechanism: All multiplexers can be put into a deep sleep state to save power. This is accomplished by setting the switching regulator driving the multiplexer channel to a low voltage and then setting the enable to a low state. The resistor (Item 29) ensures that the gate does not float high when enabled.

[0077] In conclusion, Figure 8 A detailed description of the switching mechanism is provided, emphasizing the important role of each component in smoothly connecting the cells to the multiplexed channels. The figure emphasizes the complexity of the switching mechanism and the importance of each element in ensuring control through two control lines and a unique cell connection mechanism.

[0078] Fig. 9 : Schematic diagram of energy storage column shielding grounding arrangement Fig. 9 Provides a detailed description of the shielding and grounding arrangement employed in the energy storage column. This assembly is critical to maintaining safe operation of the energy storage column and compliance with electromagnetic compatibility (EMC) standards.

[0079] Fig. 9 Key elements: • Two-wire connection (L1 and L2): The diagram depicts a two-wire connection labeled L1 and L2. L1 can be line voltage or functional earth or neutral.

[0080] • Secondary common-mode choke (item 30): The secondary common-mode choke is located at the lead entry and suppresses conducted electromagnetic interference (EMI) by reducing common-mode noise current.

[0081] • Direct L1 connection to the shield (item 31): L1 is connected directly to the shield near or at the cable entry point, establishing a common point that can serve as a functional ground.

[0082] • Main common mode choke and filter (Item 32): This component is installed to suppress high frequency noise within the system that could affect electronic equipment.

[0083] • Shielding of the compensator and optimizer PCB (Item 33): A comprehensive shield covers the compensator and optimizer printed circuit boards (PCBs) located on top of the pillars, providing protection and promoting EMC compliance.

[0084] • Shield Plate (Item 35): A PCB or solid metal shield plate is secured inside the molded cover. This shield is screwed onto the aluminum tube shield (Item 35) to form the electrical interconnect and integrate the aluminum tube into the shield.

[0085] •Metal spring cover at the base: At the bottom of the column, the metal spring cover is secured by a retaining clip ( Fig.10 Item 11) in the figure is electrically connected to each other. These clamps mechanically and electrically connect the lower end of the aluminum tube, which has an electrical step inside. This arrangement prevents differential voltages at these ends, mitigating potential EMC problems caused by these voltages. This setup Figure 6 The arrangement shown provides EMC shielding benefits, although Figure 7 There is no significant advantage. These shields also serve a safety function, maintaining the structural integrity of the system in the event of a fault condition that causes the cell to overheat.

[0086] Overall, Fig. 9 The complex shielding and grounding setup within the energy storage pillar is fully demonstrated, emphasizing its contribution to safety and EMC compliance.

[0087] Fig.10 : Detailed design of bottom injection cover and spring cover Fig.10 The design and function of the bottom molded cover and spring cover are shown in depth. These key components are used to fix the battery cell in the energy storage column, provide protection and force to the battery cell to ensure reliable interconnection, and facilitate the installation and removal process of the battery cell.

[0088] Fig.10 Key elements: • Double Seal (Item 36): The bottom molded cover features a pronounced double seal around its perimeter. This seal plays a vital role in preventing water intrusion when the column is in the upright position, effectively sealing the cell loading area.

[0089] • Battery Cell Insertion Openings (Item 37): The cover design includes multiple openings that align with the interior dimensions of the tube. These access points facilitate the battery cell insertion and removal process.

[0090] • Screw Holes (Item 38): Strategically positioned holes are integrated into the cover to match the tube's screw slots. Screws inserted through these holes securely fasten the tube to the molded cover, ensuring a secure connection.

[0091] • Spring clips (item 11): Mounted over the screw holes are U-shaped spring clips, held in place by the same screws used to secure the tube. These clips have tabs that lock the spring cover (item 12) in place. The clips can be squeezed closed (item 39) to facilitate removal of the spring cover.

[0092] • Spring Cover (Item 12): The spring cover and clip are made of stainless steel, chosen for its durability, strength, and corrosion resistance. Their electrical conductivity also provides effective shielding for the base of the column.

[0093] In conclusion, Fig.10 The design considerations within the energy storage system are shown in detail, particularly the construction of the bottom cover. It highlights the measures taken to ensure protection, accessibility and shielding of the cells within the system.

[0094] Fig.11 :Design of the bottom area of ​​the energy storage column base Fig.11 The actual implementation of the energy storage column substrate area is shown in depth. The description shows the functional elements that ensure system stability, easy accessibility and protective shielding.

[0095] Fig.11 Key elements: • Baseboard (Item 40): Central to the design is the baseboard, which can be secured to the floor using designated screw holes (Item 41). Alternative or additional attachment methods, such as liquid nails or permanent adhesives like two-part epoxies, provide flexibility during installation.

[0096] • Stainless Steel Pins (Item 42): Stainless steel pins are embedded in the design and serve a dual function. First, they help to hold the pillar in an upright position, thus ensuring stability. Second, they act as a hinge on any of the three axes (left, front or right), allowing the pillar to be tilted for easier access to the battery cells. Not shown is an additional stabilizing wall plate with pins that is inserted into the top of the pillar, ensuring that the pillar cannot be knocked over or blown over during use.

[0097] • Battery cell access opening: Fig.11 Shown is the clear opening for easy cell access. All 28 spring covers and retaining clips (item 43) are accessible through this opening, simplifying maintenance and replacement of the cells.

[0098] • Recess in base plate (item 44): A specially designed recess in the base plate accommodates the expansion foam seal. Fig.10 The dual seals shown are matched to ensure a tight fit and prevent the ingress of unwanted matter.

[0099] • Extruded Polycarbonate Reinforced Insulation (Item 45): The aluminum tubes are covered with extruded polycarbonate reinforced insulation. This insulation is shaped with grooves, similar to roofing panels, which enhances the strength and durability of the structure.

[0100] In conclusion, Fig.11 Design considerations for the base region of the pillars are elucidated to improve stability, facilitate cell entry, and protect from environmental factors.

[0101] Fig.12 : Plug and play column and tray design Fig.12 A comprehensive overview of the key elements found in standard columns and trays is provided, highlighting the plug-and-play nature of these components in energy storage systems.

[0102] Fig.12 Key elements: • Cross-braced or locked setup: This setup incorporates a mechanism to ensure that all columns are cross-braced or interlocked so that adjacent columns operate as one physical module. This includes cross-braced straps that tie the bottom of a column to the top of a nearby aligned column, or an interlocking method that prevents the columns from sliding vertically when tied together. This feature enhances the stability of the columns during shipping and eliminates movement that could affect the reliability of the system. This is critical to preventing the columns from collapsing or shifting. The preferred locking device (not shown) is an H-shaped, rotated 90 degrees sideways, placed between the columns to provide airflow spacing, with the legs of the H locking above and below the top injection molded cover.

[0103] •Under-Pallet Airflow and Vents: This design promotes efficient thermal management within the system by directing cooling air to the sides of the uprights. The space under the pallet also houses the forklift forks, which share this space under the pallet air. The risers that lift the pallet are equipped with holes or gaps to enable lateral airflow. This dual functionality effectively maintains optimal performance of the energy storage cells.

[0104] • Plug-and-play interconnection: Each pillar is equipped with multiple high-power terminals designed for both input and output. This design choice provides ample paths for the current, ensuring efficient energy transfer and redundancy. To complement these, fiber optic lines are introduced along with the electrical connections, also serving as redundant communication paths to increase system reliability.

[0105] •Quick Release Connections: The design includes quick release connections for communications and high current terminals. These connections simplify system installation, configuration, maintenance and upgrades.

[0106] •Standard Forklift Space: The bottom of the pallet is designed with enough clearance to accommodate standard forklift forks for easy movement. This feature enhances the mobility, installation and flexibility of the system.

[0107] •Lifting Points on Columns: To facilitate replacement of columns, lifting points are integrated into the column design. These lifting points allow for easy removal and replacement of columns once the pallets have been relocated to the service area Standard Size: Preferred pallets are standard size to accommodate 4 x 4 columns so that four pallets can fit neatly into a 10-foot high cube shipping container.

[0108] In conclusion, Fig.12 Design elements that contribute to easy installation, movement and maintenance of columns and trays are outlined. It emphasizes the plug-and-play nature of the energy storage system.

[0109] Fig.13 :Wiring arrangement of column energy storage system Fig.13 Potential wiring configurations for an energy storage system utilizing a column structure are shown. The flexibility of the system is highlighted, which stems from the column's ability to self-organize during the startup process. This self-organizing process enables the column to autonomously determine the wiring topology before the user defines the allowable operating parameters such as current and voltage. During this self-organizing process, the column communicates with adjacent columns and electrically exercises its outputs. This action ensures that the electrical interconnections are aligned with the topology determined by the detected communication interconnections. The arrangement is graphically presented for the user to verify that the wiring is implemented as expected, and any faults or uncertain interconnections are visually indicated.

[0110] Fig.13 Key elements: • 3 x 3 post tray (top left): This arrangement represents a typical star / delta 240V ac The system, with redundant loops, ensures continuity of operation even if a single column fails. The system software subtly adjusts the charge distribution on the columns in these loops by varying the voltage to control the corresponding current, increasing the current in overcharged columns and reducing it in undercharged columns. In this configuration, each triangle spans two columns, with one column reaching the star point.

[0111] • 4 x 3 column tray (center left): 4 x 3 tower tray (center left): This layout represents an incremental 1000 V ac system, which features a single redundant loop containing increments. Similar to a 3 x 3 post tray, this design keeps the system running even in the event of a post failure. The software coordinates the charge distribution by cleverly adjusting the voltage across the triangular loop to adjust the marginal current between posts (in addition to any current entering or leaving the system). In this setup, each triangle is spanned by four posts.

[0112] • 4 x 4 post tray (lower left): This configuration represents another triangular 1000 V acsystem, but only includes loops between parallel columns in parallel. If charge transfer between increments is required, the system employs an externally connected transformer. The software manages the charge distribution between increments by adjusting the voltage to control the corresponding current, increasing the current in the overcharged column in one increment string and reducing the current in the undercharged column in another increment string. In this arrangement, the external transformer facilitates current sharing.

[0113] • 4 x 4 post pallets and 2 x 2 pallets in a 10-foot container (right): This layout represents a 1000 V ac The triangular system, with loops around the four parallel pillars and three triangles, presents multiple layers of redundancy. Charge transfer between increments is as described for the 4 x 4 pillar tray. The software assists the commissioning process by automatically drawing a topology diagram. As shown, two triangles contain five pillars in series and the third contains six pillars. Each pillar adjusts the current they each contribute or extract from the source to maintain an evenly distributed charge level and adhere to the predefined charge and discharge profiles.

[0114] The system incorporates the ability to stress test connections prior to commissioning or during maintenance where a loop exists. Initially, the system is disconnected from the power supply. The columns in each loop work in turn - either providing a safe, ultra-low voltage throughout the system, directing the high test current, with the non-test column effectively acting passively, bypassing the current, or all columns work together to test, with one column providing both positive and adjacent negative steps or voltages around the loop, reducing the total test time. This test lasts long enough that any high resistance joints will heat up, facilitating fault detection using a thermal imager. Once testing and inspection is complete, the operator can exit test mode and reconnect the system to power.

[0115] In conclusion, Fig.13 The flexibility and adaptability of the system was highlighted, demonstrating a range of configurations to enable varying levels of redundancy, ease of pre-operational integrity testing, and the ability to accommodate varying voltage requirements.

[0116] Other features in a column-based energy storage system (not shown): Other features included in column-based energy storage systems collectively improve the overall performance, reliability, and ease of maintenance of the system.

[0117] Key Points: • Parallel columns: Columns can be connected in parallel to enhance reliability, increase storage, or increase current capacity. In this configuration, they work together to sum the voltage and provide or consume the necessary power.

[0118] • Charge management: The columns in a string or loop communicate and individually fine-tune their voltages to control their power flow and resulting charge levels, ensuring optimal charge distribution throughout the system.

[0119] • Test regimes: The column can be disconnected from the power system and subjected to various test procedures including high current testing, high column voltage stress testing and high dV / dt column voltage stress testing. These tests are critical to monitoring column performance and identifying potential deterioration or defective components.

[0120] • Leakage Test: The system performs leakage tests to detect any leakage current in the system, especially between the cells and the tubes enclosing the cells, which may be a sign of moisture ingress or insulation degradation. These tests are performed during the shutdown phase or when no current is required to flow through the column. The column drives its voltage high or low relative to L1 (such as Fig. 9 ) and then isolating its corresponding MOSFET. By measuring the voltage drop across the cell and comparing it to the rate of drop expected for a known current (such as the current required for the voltage measurement), any leakage current can be confirmed or assumed to be insignificant. This process ensures that any significant leaks are discovered and addressed promptly.

[0121] •Double Insulation: Each pillar is equipped with double-layer double insulation and insulation overlap to ensure sufficient creepage distance and provide stronger protection for the internal battery cells.

[0122] • Battery Cell Replacement: The system design greatly simplifies the battery cell replacement process. By tilting the column downward on a hinge consisting of a stainless steel pin (item 42), a base plate (item 40) and a bottom molded cover ( Fig.10 ) - provides access to the area where the cell spring push rod (item 12) is released by pressing the retaining clip (item 11). Once this step is completed, the spring mechanism can be removed to allow access to the header PCB. This accessibility allows for straightforward removal of old cells and installation of new ones.

[0123] • Installation and wiring: For large capacity energy storage columns, Fig.11 The designs shown are subject to slight variations. Specifically, hinge arrangements may not be included if deemed necessary. The columns are designed to fit neatly into recesses on the pallet, simplifying installation, delivery, and removal. Additionally, the columns are designed with plug-and-play capabilities to accommodate dual wiring and communication paths for both inbound and outbound connections. It is also important to note that the columns mounted on the pallet do not require an additional base plate, as the pallet performs this function. Additionally, the lifting points included in the bottom molded cover (e.g. Fig.10 shown) allows a dedicated removal cart to lift and easily remove the column.

[0124] • Overvoltage Surge Protection: The column is designed to protect itself from overvoltage surges primarily by opening the MOSFET. This response acts to resist the surge voltage and redirect any resulting current through the compensator’s cells and storage capacitors using the body diode of the open MOSFET. During a surge event, the compensator, while monitoring the surge current and voltage on its storage capacitors, can: —Activates dedicated sacrificial series MOSFETs to self-destruct as a final measure of protection. These back-to-back sacrificial MOSFETs are fully on during normal operation. However, if a surge occurs and the compensator can no longer absorb the surge, they are triggered to shut down and the momentary self-destruction of the additional voltage does not stop the surge. This action resists further voltage surges, protecting the compensator and the rest of the system from potential damage.

[0125] —Or install a metal oxide varistor (MOV) on the compensator and arrange back-to-back MOSFETs between the compensator and the nearest optimizer. The MOV has a fully on voltage lower than the combined back-to-back MOSFETs, as well as the maximum voltage the compensator can handle. In this setup, the MOV carries the surge current, and the compensator and additional MOSFET layers resist the voltage, further protecting the system from damage.

[0126] Overall, this highlights the complex design features and protection measures integrated into column-based energy storage systems, demonstrating their robustness, operational flexibility, and ease of maintenance.

[0127] Additional features for high operating voltage (MV or HV) (not shown) High voltage operation requires additional features to equip column-based energy storage systems with higher operating voltages. These features reflect system adaptability, safety measures, and a positive attitude towards electromagnetic compatibility (EMC).

[0128] Key aspects of medium or high voltage: •Supplementary Insulation: In situations where a higher operating voltage is required, a third layer of insulation is added. This additional layer can be strategically placed between pallets or used to line up shipping containers or spaces, increasing the safety and reliability of the system.

[0129] •Safety Measures: Implement special precautions to protect personnel from potential exposure to high voltage system components during operation. These measures may include installing gates, doors, locks, or warning signs to ensure safe operation of the system.

[0130] •EMC compensation: In high voltage applications, electromagnetic compatibility is managed by using a shipping container that acts as a Faraday shield or by using dedicated shielding. In this arrangement, active compensation can be avoided and the system generates a pure sine wave by stepping and introducing PWM into the series choke. Additional filtering assisted by capacitors produces a smooth and stable waveform, thus ensuring optimal EMC.

[0131] Overall, this highlights the flexibility, safety and adaptability of columnar-based energy storage systems. It provides insights into how the system can be tailored to meet various application and voltage requirements, thereby demonstrating its wide operating range.

[0132] Each feature consists of numerically identified items. These items are described in detail below: Item 1—Battery Cells. The cells used in this example are cylindrical 33140 cells, typically 33mm in diameter and 140mm in length. Each cell is wrapped with a heat-shrinkable insulation layer. This embodiment is designed for cells with lithium iron phosphate (LiFePO4) chemistry. When fully charged or overcharged, LiFePO4 cells effectively become an open circuit, a condition that disrupts the series current charge balance common in lead-acid cells. This requires careful monitoring and balancing to ensure uniform charging between cells of this type. Although this model uses LiFePO4 cells, other types of cells can be used, which may have unique materials or alternative chemistries. These alternative cells may show greater leakage when fully charged, similar to lead-acid cells, thereby reducing the need for individual cell balancing and monitoring. In this system, 24 cells are connected in series, with each cell having a platform voltage of 3.2V, resulting in a nominal operating voltage of 72V. This embodiment can achieve a maximum voltage of 86.4V when the cells are fully charged at 3.6V.

[0133] Item 2 - Balancing and Monitoring (BMS) PCB, which is slightly longer than the relevant battery cell, with its top and bottom ( Figure 5The topmost PCB has a male edge connection and flange (not shown) for alignment with the injection molded part (item 17) to facilitate pushing the edge connector into its mating part when the cells are pushed onto the underside of the injection molded part. The bottommost BMS PCB has a flying lead connected to the fuse circuit board (item 21) for balancing and monitoring the connection of the bottom cell. The BMS is designed to operate at multiplexed voltages up to 100 V, which provides ample headroom for this system as it is designed for a maximum operating voltage of 86.4 V.

[0134] Item 3 - Insulation Plates These are flexible rectangular plates made of a durable, semi-rigid, flame-retardant insulating material such as PVC. They slide into the length of the tube (Item 6) and overlap the PCB rails (Item 5). The overlap ensures that the creepage distance is appropriate for the applied step voltage.

[0135] Item 4 - Screw fixing slots, these slots are formed in the extruded tube material and are provided with flanges (not shown) to allow the PCB rails (Item 5) to be securely locked, thereby firmly securing the rails to the sides of the tube. These slots are designed to accommodate No. 8 self-tapping screws.

[0136] Item 5 - PCB rail, this extruded rail slides easily on the flange of the screw slot (item 4), providing a smooth surface for the BMS PCB to slide. The rail is equipped with a flange overlapping the insulating plate (item 3) (as shown) and a fixing section (not shown) that clips on the screw slot flange to fix the rail to the tube side.

[0137] Item 6 - Tubes, made of extruded aluminum, these tubes have screw slots (item 4) and flanges for fixing to the PCB rails (item 5). The shape of these tubes is suitable for accommodating the cells, with quarter-radius corners for four-cell tubes and half-radius corners for two-cell tubes.

[0138] Item 7—Level Switching,This feature is shown in the diagram, indicating where the switching occurs. The goal is to minimize the length of the copper loop that the current flows through. In this example, the MOSFETs are arranged back to back. This layout allows direct airflow to cool the MOSFETs in a virtual corridor. When the system is running at high power levels or when a connected temperature sensor signals that cooling is needed, a fan drives air along this path.

[0139] Item 8 - Cell Pack Interconnection and Balancing, the oval symbols shown indicate the location of the cell pack interconnections. These interconnections are optimized to maximize copper utilization while minimizing path lengths and may extend across the full width of the four two-tube cell packs. Figure 2B In the case of Figure 4B In the case of a flying capacitor, it extends to the width of the tube. With a typical flying capacitor arrangement, the capacitor size is chosen to prevent a significant imbalance from overloading the associated MOSFET switching the flying capacitor level. Nevertheless, it is still large enough to balance the required currents at the maximum switching frequency. To ensure reliability of the board, film or ceramic capacitors are used. The inductor is placed in series to create a series tuned circuit at the required switching frequency. With a series inductor, overload protection can be achieved using smaller capacitors and frequency shifting, eliminating the need for further overcurrent protection. Series PTCs (positive temperature coefficient resistors) have been considered as a potential alternative protection mechanism.

[0140] Item 9 - Interconnection In this example, a double row of standard header pins is used for interconnection with the associated PCB, a secondary board containing an inverter, or a compensator. Each connection has 40 male / female pins, ensuring a highly reliable multi-redundant interconnection.

[0141] Item 10—Cell Terminals, This design utilizes standard stainless steel round head retaining bolts for these top cell terminals. The injection molded cover, shown by its edge in (Item 23), includes a groove into which the square locating head of the bolt locks. A nut is also included that is tightened to secure the coach bolt in place. After all 56 bolts are tightened, split or thin star washers can be added to improve the electrical connection to the PCB (Item 15). The PCB is then placed over the bolts, and additional washers (either split or star shaped) are then placed and more nuts are used to secure the PCB. M6 bolts and nuts were used in this example.

[0142] Item 11 - Spring Clips, these clips have flanges that hold the spring cover (item 12) and are tightened to clamp the bottom molded cover to the aluminum tube. The screws that hold the clips in place are screwed into the screw slots in the tube (item 4). These spring clips allow the spring cover (item 12) to slide over. The flanges then pop out and lock into the sides of the grooves in the spring cover, preventing removal of the cover without the proper tools.

[0143] Item 12 - Spring cover, made of thin stainless steel (0.6mm in this case) with the edges bent upward to hold the plastic moulded part that holds the spring in place. The middle of the cover is convex downward from the centre to prevent the cover from deforming under the retained spring force.

[0144] Item 13 - Reservations Item 14—BMS edge connector, the battery management system (BMS) is controlled by four lines, see Figure 8 . These lines are: • Enable: Open circuit or 0V = BMS no channel enabled; Battery positive voltage = all BMS channels enabled.

[0145] •Multiplexer on: switch 10 to 0V = multiplexer off; switch 0 to 10V = multiplexer on.

[0146] • Multiplexer A: First multiplexer channel (multiplexer connected to +ve of odd numbered cells) • Multiplexer B: Second multiplexer channel (Multiplexer connected to +ve of even numbered cells).

[0147] The edge connector has 6 pins. Multiplexer A and Multiplexer B are connected via two pins of the edge connector to ensure reliability and according to Figure 8 The description senses the cell voltage and carries the balancing current.

[0148] Item 15 - High Level BMS, this board is designed to manage Figure 6 and Figure 7 The ends of all 28 cell strings shown feature gold immersion connections for reliable, corrosion-free connection with retaining bolts. Their dual primary functions are: •like Figure 6 As shown, the circuit board achieves high-level balance of the battery string group by adjusting the forward or reverse switching time.

[0149] •according to Figure 7 , which allows high-level balancing of cell strings using a flying capacitor topology.

[0150] The board is designed with two medium power (0.5A) switching regulators that can vary the voltage from 0V to the positive battery voltage.

[0151] The high-level BMS, also called the optimizer board (Item 15), interacts with the string BMS (Item 2) to measure and correct the voltage or charge level of a specific cell in several steps: • Activation of the multiplexer system: Activate the multiplexer system by setting Enable to the positive voltage of the cell, assuming it is not already enabled.

[0152] • Changes to multiplexer on: The board switches “MuxOn” to a low state (0 V).

[0153] • Tube Multiplexer Selection: This board enables the multiplexer for a selected one of the four dual tubes by activating the gate of the corresponding MOSFET mounted on the optimizer board, which electrically connects the regulator to the selected tube (not shown).

[0154] • Regulator adjustment: Set the two switching regulators to voltages close to the two cell voltages. These are typically set to the expected voltages at the positive terminals of adjacent even and odd cells.

[0155] • Regulator Configuration: The switching regulator is then configured in a high impedance state, disabling its MOSFET and allowing the regulator capacitor to maintain the set voltage.

[0156] • Changes to multiplexer on: The board switches “MuxOn” to a high state (10V).

[0157] • Cell connection: The cell with the voltage closest to the set voltage is connected according to Figure 8 The guide described in the connection.

[0158] • Multiplexer voltage measurement and charge regulation: Measure the voltage at each multiplexer. Abnormal or unexpected voltages are recorded and reported when assessing which cells may need premature replacement. The switching regulator is then enabled and regulated to a voltage appropriate for charging or discharging the connected cells. The voltage is measured when the regulator is enabled, and the voltage step thus measured is used to estimate the current flowing into or out of the selected cell.

[0159] • Iteration: Repeat the entire sequence for the other cells.

[0160] This detailed and methodical process ensures that the Advanced BMS board coordinates with the optimizer board to provide efficient and effective management of the battery system.

[0161] Item 16 - Reservations Item 17—BMS Push Rod, this molded part is connected to the Battery Management System (BMS) board. It ensures that the BMS is pushed into the tube by the battery cell so that when the battery cell is fully installed on the associated retaining bolt, the BMS is fully pushed into its connector.

[0162] Item 18—Cell terminals protruding above and below the BMS PCB and connected to Figure 5 Between the cells shown horizontally. In this case, the surface of the lug that mates with the cell has 0.2 mm high dots. The dots ensure that any corrosion does not cause the mating surfaces to separate. For optimal reliability, silicone grease is applied to the surface and the dots help retain the grease through capillary action.

[0163] Item 19 - Terminals These terminals mounted on the header PCB may be similar in design to the flanges described in (Item 18). Alternatively, they may be slightly domed to achieve a similar result.

[0164] Item 20—Fuse, this is a standard surface mount fuse. For either design, use a low voltage (<100 Vdc) fuse. Figure 7 In the design, these fuses have a higher current rating than the inverter input fuse, so it will blow first.

[0165] Item 21 - End plate PCB, which connects the two ends of each string of 12 cells and includes a flying lead for the BMS PCB connection. This PCB applies a huge force of 4 kg to 20 kg to each string of cells, ensuring reliable and long-term electrical connection.

[0166] Item 22 - Cell string springs. These powerful springs are used in pairs in each double tube. When fully compressed, they exert a force of more than 10 kg, keeping all the cells in the string tightly packed together for optimum performance.

[0167] Item 23 - Injection molded top cover (its bottom edge) This identifies the bottom edge of the injection molded top cover, which has the task of holding all the battery cells firmly in place, ensuring structural stability and alignment.

[0168] Item 24 - Bottom BMS PCB to End Plate PCB Wire. This wire facilitates the connection between the bottom BMS PCB (item 2) and the end plate PCB (item 21). It is designed to be long and strong, allowing the end plate PCB to be removed for cell polarity and charge checks if necessary. Checks are made using a dedicated test piece or a multimeter. This wire is strong enough to act as a draw cord to pull the cells out of the tube if necessary.

[0169] Item 25 - Control signal capacitor / resistor, this component couples the control signal to manage the corresponding multiplexer (mux). The capacitor is rated to exceed the string voltage, allowing it to block the control signal voltage to the multiplexer or cell voltage. It has enough capacitance to maintain the drain charge on the multiplexer MOSFET for the sampling period, nominally 1ms is sufficient. The resistor in this setup limits the current into the desaturation transistor and the Zener voltage limiter (Item 27), preventing forced turn-on of the multiplexer MOSFET or overloading of the control driver when operating multiple BMS PCBs.

[0170] Item 26—Emitter coupled transistors, which are coupled to the connected sources of the multiplexed MOSFETs, with their collectors connected to the gates of the same MOSFETs. Their purpose is to turn off the MOSFETs when they desaturate. The voltage level at which desaturation occurs is set by a voltage divider across the drains of the MOSFETs to the bases of these desaturation detection transistors.

[0171] Item 27—Zener voltage limiter, this component consists of two transistors connected across the source / gate of the MOSFET, acting as a zener, limiting the gate voltage. The two transistors are connected in series, and the maximum voltage at the MOSFET gate is determined by the series reverse emitter junction breakdown. Transistors are well suited for this role because they have a very sharp knee voltage, which is a result of the reverse breakdown of the emitter-base junction.

[0172] Item 28 - Enable Input Regulator, This set of components helps enable the multiplexer (mux) or shut it down to a low power state. This setup consists of three basic parts: a high value resistor, a connected diode, and a second diode. The high value resistor is used to bias the connected diode when the multiplexer is enabled. The second diode acts to pull the MOSFET gate low, turning off all MOSFETs when the enable input is pulled low.

[0173] Item 29 - The pull-down resistor, this resistor plays a vital role in ensuring that the MOSFET remains "off" when not actively controlled. It does this by creating a current path that ensures the voltage across the MOSFET gates remains low, preventing them from turning on when the enable input is allowed to float.

[0174] Item 30 - External common mode choke, this component is used to further reduce any conducted leakage in the system. A common mode choke is an electrical filter that helps block interference and noise on the line, in this case the choke adds a layer of noise reduction to ensure interference is minimized.

[0175] Item 31 - Common Bonding Point, this is the point of connection to the functional ground or shield common point. It is a critical component to ensure EMI is kept to a minimum while providing grounding for the system, contributing to the overall safety, compliance and functionality of the system.

[0176] Item 32 - Filtering Components This part filters the compensation step. Notably, it includes a snubber consisting of a capacitor and resistor designed to dampen or "buffer" the ringing caused by any perturbations resulting from the repetitive slight out-of-time steps. The ideal capacitor has been found to range between 0.1 and 0.5 times the value of the line capacitor placed across the choke. When a 0.47 pF snubber capacitor is used, the optimum resistor is a 5 W resistor between 10Ω and 50Ω.

[0177] Item 33 - Shielding, said shielding consists of three main parts to protect the system and reduce interference. It includes a top shield surrounding the PCB and electrically screwed to said aluminum tube (schematically shown as (Item 35)), said aluminum tube (Item 34) and said spring cover (Item 12). The spring clip (Item 11) electrically connects these parts.

[0178] Item 34—Aluminum tubes—These tubes house the battery cells and provide shielding and protection from any potential overheating events that could cause external damage to the column.

[0179] Item 35 - Top Guard, this is the portion of the top guard that screws onto the aluminum tube. It is a key component that provides additional protection and stability to the system.

[0180] Item 36 - Dual ribs designed to mate with a closed cell or silicone seal (Item 44) located in the base. The dual ribs can also accept a bead of silicone grease to create an IP67 waterproof seal, or simply rest against the base seal to achieve an IP65 to IP66 seal.

[0181] Item 37—Battery cell installation opening, which is the opening through which the battery cells can be installed and removed.

[0182] Item 38 - Mounting Hole, this is the hole in the spring clip and the injection molded base for use with a No. 8 self-tapping tool to attach the clip (Item 11) and the base plate ( Fig.10 ) is fixed to the tube (item 6).

[0183] Item 39—Pressing Spring Clip, which item describes how to press the spring clip (Item 11) to remove or install the spring cover (Item 12).

[0184] Item 40—Base plate, also injection molded, with horizontal holes on three sides into which stainless steel pins slide to allow the cells to be replaced by a hinge action. The pins are mounted on both sides to secure the column or any of the three sides to enable it to be placed left, forward or right.

[0185] Item 41 - Screw holes for fixing the base, these are the screw holes for fixing the base plate. The bottom surface has a cross pattern that allows for secure embedment of gap filling materials such as wet cement, liquid nails or epoxy. The filling material ensures that the base plate is firm and stable, not the pile foundation material in the gap.

[0186] Item 42—Stainless steel pins that slide along one or both sides of the column. The bottom molded cover has a solid flange with holes to accommodate these pins and is suitable for lifting the weight of the cell and column without appreciable deformation of the base plate (Item 40) or the bottom molded cover.

[0187] Item 43—Spring cover assembly, this figure identifies two spring covers and more generally identifies the bottom injection molded cover assembly.

[0188] Item 44—Seal groove, a closed cell foam or silicone seal groove that mates with the double ribs of (Item 36). This seal is designed to form a watertight enclosure when mated with the ribs.

[0189] Item 45—Extruded polycarbonate reinforced insulation is used to cover the aluminum tube, providing protection and additional strength. The insulation is shaped with grooves, similar to the grooves in roof panels, to increase its durability. It consists of four corners and connecting pieces in the middle of each side. The bottom injection molded cover has a deep groove into which the insulation can be inserted. When assembled together and stretched to fit over the tube, the insulation is self-sealing and self-tightening via interlocking devices (not shown). For enhanced IP protection, the bottom is sealed with an open cell foam material placed in the groove before the extrusion is added. In another embodiment, the base is filled with a bonded sealing material before the insulation is slid into place. The outside flange of the groove is lower than the inside to prevent water from entering the housing. BRIEF DESCRIPTION OF THE DRAWINGS

[0190] Figure 1 is a top view of an extruded aluminum tube for battery storage and shows a top view of an extruded aluminum tube designed for battery storage. This view reveals the effective organization and safety measures considered for this battery system. Key components include the battery cell and PCB, extruded screw holes, double insulation, PCB clamps, and overlapping insulation layers. These features ensure a safe, well-insulated and robust environment for the battery cell while providing a stable framework for electrical balancing.

[0191] Figure 2Ais a perspective view of an AC battery energy storage grid, providing an angled perspective view of an AC battery energy storage grid. The grid consists of aluminum tubes arranged in a 4x7 arrangement, organized in a way that allows for stepped AC voltage. Important features include the location of the switches that produce the stepped voltage, the interconnection with the compensator, and the compact size of the system. The diagram shows how the grid converts the stored DC power into a usable AC output, and the role of the compensator in producing a suitable sine wave for use.

[0192] Figure 2B is a perspective diagram of a DC battery energy storage grid, showing a similar Figure 2A A DC battery storage grid is designed to be used in an AC grid, but is designed to generate a DC voltage for the inverter. Key features shown include the interconnection between the cell packs, the flying capacitors for balancing, and the arrangement of the DC output of the inverter. The diagram highlights the flexibility of the system in providing different electrical configurations and shows the role of the inverter in converting the high voltage DC output to AC.

[0193] Figure 3 An alternative tube configuration for four-cell storage is depicted. A rounded square design is shown to accommodate four cells, making Figure 1 The design in the 2018 UPS doubles the storage capacity per tube. Key features include increased redundancy, fewer balancing components due to parallel connections at each layer, and the use of fuses to ensure system safety and reliability. Despite the increased storage capacity and redundancy, the configuration effectively manages potential risks such as excessive current or arc flash.

[0194] Figure 4A is a perspective view of a four-cell AC cell energy storage grid, showing the use of Figure 3 3D top view of a grid layout that produces a stepped AC voltage using the modified tube design in Figure 1. This layout demonstrates the conversion from stored DC to usable AC output via the labeled switch positions. The diagram also shows the interconnection to the compensator, which is essential for converting the step AC into a sine wave suitable for use. Despite the increase in storage capacity, the system maintains a compact design of the same size as the previous design. Figure 2A and 2B This more compact arrangement increases storage capacity compared to conventional .

[0195] Figure 4B is a perspective view of a four-cell DC battery storage grid, Figure 4A Similar, but aligned to a DC electrical configuration designed to generate DC voltage for the inverter. This grid configuration shows the interconnection between the cell groups, the flying capacitors for balancing, and the arrangement of the high voltage DC output to the inverter. Figure 4AAs shown, the system design maintains a compact size and layout, showing the modified aluminum tubes adapted to the four-cell configuration. With the increased storage capacity, it is able to accommodate approximately 14% more energy storage in the same volume.

[0196] Figure 5 is a side view of a dual tube configuration showing a side view of a dual tube battery storage system where the cells and balancing and monitoring board are housed within the structure. Key features include coach bolts for securing the printed circuit board (PCB), cells and edge connectors, a balancing and monitoring board (BMS) with bronze terminals for electrical connections, and a spring loaded insert with a PCB fuse board at the tube end. This diagram provides a comprehensive overview of the dual tube configuration, showing the importance of each component and its role in the system.

[0197] Figure 6 Figure 1 is a schematic diagram of a PCB layout for a step-by-step sine wave approximation, showing the schematic layout of a PCB for a step-by-step approximation of a sine wave using primarily N-channel MOSFETs. Aspects of note include copper protection to prevent board damage due to cell short circuit events, reference voltage for the MOSFET drivers to prevent unnecessary switching, multiple 100V switching MOSFETs connected in parallel to reduce switch resistance, and connectors for the battery management system (BMS) PCB string.

[0198] The schematic also highlights the presence of an “optimizer” that has a dual function: it controls the storage cells to produce an approximation with high power conversion efficiency and works with the compensator to manage the switching times of the charge and discharge cycles. Figure 6 Provides a comprehensive blueprint of PCB design and its integral role in energy storage systems.

[0199] Figure 7 This is a schematic diagram of a high voltage DC PCB layout for an inverter, illustrating the PCB layout designed for a flying capacitor balancer, designed to balance strings of cells in series. Notable features include copper protection to ensure safety from cell short circuits, cell strings and balancing capacitors, with positive temperature coefficient (PTC) thermal fuses for current limiting, voltage monitoring for adjusting switching frequency, and 28 connectors for the battery management system (BMS) PCB string. The diagram demonstrates effective design practices for improving system safety and reliability, showing how all interconnect paths pass through the PCB, eliminating the need for external wiring.

[0200] Figure 8Figure 2 is a schematic diagram of the switching mechanism used to connect the cell terminals to the multiplexer channels. It details the switching mechanism used to connect the cell terminals to the multiplexer (Mux) channels. The main elements include the resistor-capacitor pair that controls the state of the multiplexer MOSFET (item 25), the desaturated NPN transistor designed to prevent potential damage from voltage spikes or excessive current in the multiplexer (item 26), the series reverse emitter-base junction that enables the multiplexer to remain on for long periods of time (item 27), the dual channels for accessing individual cells, and the shutdown mechanism for saving power. The figure highlights the complexity of the switching mechanism and the importance of each component in managing the connection of cells to the multiplexer channels in a robust, overload-protected manner.

[0201] Fig. 9 The shielding and grounding arrangement of the energy storage column is shown in the figure below. This setup is essential to maintaining the safety and electromagnetic compatibility (EMC) standards of the column. Key elements include two-wire connections (L1 and L2), secondary common mode chokes for EMI suppression (item 30), shielding of L1 directly connected to the common point (item 31), main common mode choke and filter for high frequency noise suppression (item 32), comprehensive shielding of the compensator and optimizer PCB (item 33), shielding plate fixed inside the cover (item 35), and base metal spring cover for EMC shielding and structural safety.

[0202] Fig.10 is a detailed design of the bottom molded cover, and the spring cover provides a detailed description of the bottom molded cover and the spring cover. These components are critical to the overall safety and functionality of the energy storage column, ensuring reliable interconnection of the battery cells and facilitating the installation and removal of the battery cells. Important elements include double seals to prevent water intrusion (item 36), openings for inserting the battery cells (item 37), screw holes for securing the tubes (item 38), spring clips for locking the spring cover (item 11), and durable, corrosion-resistant spring covers that provide effective shielding (item 12). This figure emphasizes the thoughtfulness behind each design decision, reflecting the emphasis on protection, accessibility, and efficient shielding.

[0203] Fig.11is a detailed view of the baseplate area of ​​the energy storage column, providing a careful breakdown of the design and construction of the foundation area of ​​the energy storage column, highlighting essential features that contribute to system stability, accessibility, and protective measures. The design showcases a solid baseplate (item 40) designed for multiple mounting options, complemented by stainless steel pins (item 42) that ensure system stability while also doubling as functional hinges for ease of operation. The design also includes transparent cell access ports, dedicated recesses in the baseplate (item 44) that house an expanding foam seal to prevent intrusion, and the application of an extruded polycarbonate reinforced insulation layer (item 45) to increase the overall strength and durability of the system.

[0204] Fig.12 It is a plug-and-play column and pallet design that fully explores the plug-and-play characteristics of columns and pallets in energy storage systems. Design considerations include cross braces or locking devices for improved stability and system reliability, under-tray airflow and vents for optimal thermal management, plug-and-play interconnections to promote efficient energy transfer and redundancy, quick-release connections to simplify system installation and maintenance, space for standard forklift forks, enhanced system mobility, lifting points on the column to facilitate column replacement, and standard sizes that fit neatly into a 10-foot high cube shipping container. Elements of this design emphasize the ease of installation, mobility, and maintenance of the system.

[0205] Fig.13 The wiring arrangement of a pillar-based energy storage system fully illustrates the possible wiring configurations of a pillar-based energy storage system, emphasizing its flexibility, autonomous self-organization capabilities, and various layout options for achieving different redundancy and voltage requirements. The layout includes a 3 x 3 pillar tray (upper left) representing a typical star / delta 240 V with redundant loops ac System; a 4 x 3 post tray (center left), example delta 1000 V with single redundant loop ac system, a tray of 4×4 columns. Significantly, the software that manages the system assists with charge distribution by cleverly regulating the voltage to control the corresponding current flowing through the columns. The system also includes a connection stress test capability prior to commissioning or during maintenance. This detailed diagram highlights the adaptability and resilience of the system to meet a variety of operational requirements.

Claims

1. The present invention is an energy storage system comprising: A plurality of elongated compartments, each of the compartments being designed to accommodate a string of energy storage cells; Each of said compartments is provided with an accessible opening designed to facilitate installation and removal of said energy storage cells; The compartment is designed to accommodate two or more energy storage cells, which are placed adjacent to each other at their ends; Also included is a holding structure for firmly pressing the battery cell string together to form a reliable current path; The system includes a balancing mechanism; the mechanism includes a balancing system, which includes electrical tabs connecting adjacent battery cells at their junctions and structures capable of moving charge into and out of these tabs; this movement of charge helps charge or discharge the battery cells, thereby maintaining voltage balance throughout the system.

2. The system according to claim 1, characterized in that: The balancing mechanism is equipped with a sensing unit, which actively measures the voltage level of the energy storage cell through a multiplexing device; the system also has a programmable voltage regulator, which is connected to the cell through the multiplexing device; the sensing unit, voltage regulator and multiplexing device work together to balance the measured or calculated voltage level on the entire energy storage cell string contained in each of the elongated compartments.

3. The system according to claim 1, characterized in that: The balancing mechanism adopts a flying capacitor structure.

4. The system according to claims 1 to 3, characterized in that: The plurality of elongated compartments are formed from an aluminium tube which includes the retaining means for printed circuit boards; these PCBs are located between two or more battery cells.

5. The system according to claim 4, characterized in that: A second layer of insulation is applied between the battery cell and the aluminum; the retaining structure is composed of an insulating material that extends beyond the insulating layer between the battery cell and the aluminum, thereby providing sufficient creepage distance to ensure safe operation given the voltage of the system.

6. The system according to claims 1 to 5, characterized in that: Applying an additional layer of insulation to shield the exterior metal surface creates a system with reinforced insulation, protecting personnel from potentially dangerous voltages.

7. The system according to claim 6, characterized in that: The additional insulation layer consists of extruded interlocking plastic corrugated material.

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

9. The system according to claims 1 to 8, characterized in that: The energy storage cells in a string are welded together before installation.

10. The system according to claims 1 to 9, characterized in that: The connecting piece of the balancing mechanism is combined with a spring pin and is used to contact the electrical sensing terminal of the battery cell.

11. The system according to claims 1 to 10, characterized in that: The elongated compartment is vertically mounted on a base plate; the base plate is detachable from the elongated compartment by hinges or pins, thereby facilitating installation and removal of the battery cell string.

12. The system according to claims 1 to 11, characterized in that: The cell strings are held in place by cell string springs which are also held in place by spring covers.

13. The system according to claim 12, characterized in that: The spring cover is secured by a spring clip and can be released by pressing a lug of the spring clip using a tool.

14. The system according to claim 12, characterized in that: The spring cover is secured in place by a twist lock or latch mechanism.

15. The system according to claims 1 to 14, characterized in that: An AC voltage suitable for connection to the power system is provided by a connected inverter.

16. System according to claims 1 to 14, characterized in that: An AC voltage suitable for connection to the power system is generated by a stepped string of cells that produces a stepwise approximation of a sine wave and a series compensator that smoothes the voltage steps, thereby generating an AC voltage.

17. The system according to claim 16, characterized in that: The compensator is an active device that generates 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, characterized in that: The compensator includes an inductor that feeds a filter capacitor.

19. The system according to claims 1 to 18, characterized in that: A column that produces an alternating voltage.

20. The system according to claims 1 to 19, characterized in that: The columns are connected in series in a loop, with tiny voltage adjustments used to maintain charge balance on the storage cells, resulting in an unbalanced current flow that causes one column to charge or discharge in preference to another.

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