Energy storage system including multi-level battery management system

Abstract

The present document relates to an energy storage system (ESS) including multi-level battery management systems. The ESS comprises: a plurality of first-level battery management systems (BMSs) for monitoring voltage state information and temperature state information about each of a plurality of battery groups; a second-level BMS configured to generate report information on the basis of the voltage state information received from the plurality of first-level BMSs and perform an emergency response control operation on the basis of the temperature state information; and a third-level BMS configured to determine whether to perform balancing on the basis of the report information received from the second-level BMS, and transmit a balancing command, dependent on the determination about whether to perform balancing, to the second-level BMS.

Description

Energy storage system including multi-level battery management system

[0001] The following description is about an ESS (Energy Storage System), and more specifically, an ESS that efficiently separates and processes voltage balancing-related operations and emergency response control operations in an ESS that includes a multi-level BMS (Battery Management System).

[0002] With the recent expansion of electric vehicle (EV) use, EV chargers are being installed in various locations. However, the use of EV chargers increases the grid's electricity consumption and can impact other electricity usage within the space. In particular, when electricity consumption surges, the use of EV chargers is restricted.

[0003] In addition, various electric-powered mobility devices are being proposed, including not only current electric vehicles but also UAVs (Uncrewed Aerial Vehicles) and personal mobility devices that require battery charging.

[0004] Accordingly, a power system including an ESS is proposed to stably charge the various electric-powered mobile devices described above in a space where a charger is installed, and to support this.

[0005] In general, ESS refers to a device that stores energy in various energy storage devices and then supplies the stored power back to the grid when needed. Among these ESS, those that utilize batteries as energy storage devices are specifically referred to as BESS (Battery Energy Storage System). However, unless otherwise specified, the following description assumes BESS.

[0006] Typically, an ESS consists of a battery, a battery management system (BMS), a power conversion system (PCS), and an energy management system (EMS). A battery contains one or more cells, multiple cells forming a module, and multiple modules forming a pack or rack. An ESS configured in this manner can receive power by connecting to a power grid, electricity grid, or other source of power.

[0007] However, in the case of lithium-ion batteries (LIBs), which are currently the most popular, they can be used in a limited voltage range that takes battery safety into consideration when applied to ESS, and in the case where a voltage imbalance occurs in a specific battery or group of batteries in the BMS, it is considered the same as an emergency situation caused by other reasons such as high temperature and is operated in a way that controls it, which limits its use.

[0008] In addition, in the case of LIB, when applied to ESS, in consideration of the risk of fire, it is operated in a way that the cell or module corresponding to the BMS is blocked when the signal of a specific BMS is missing or the voltage of a specific cell is at a very low level close to 0V. However, when the ESS is applied to a remote area or a war zone where easy access for maintenance is difficult, there are restrictions on its use.

[0009] In order to solve the above-described problem, one aspect of the present invention proposes an ESS for implementing a method of efficiently distinguishing and processing voltage balancing-related operations and emergency response control operations.

[0010] In a specific embodiment, we propose an ESS including a multi-level BMS for efficiently performing voltage management and emergency response control of the ESS, and propose the type / requirements of batteries for implementing the same.

[0011] On the other hand, unlike LIB, we propose an ESS that utilizes acquired BMS information to maintain charge and discharge of corresponding cells or modules for a predetermined cycle even when a specific BMS signal is missing or the voltage of a specific cell is at a very low level close to 0V by applying a battery with a certain level of fire safety or higher.

[0012] The problems to be solved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0013] In one aspect of the present invention for solving the above-described problem, an energy storage system is proposed, comprising: a plurality of first-level BMSs for monitoring voltage status information and temperature status information of each of a plurality of battery groups; a second-level BMS configured to generate report information based on the voltage status information received from the plurality of first-level BMSs and to perform an emergency response control operation based on the temperature status information; and a third-level BMS configured to determine whether to perform balancing based on the report information received from the second-level BMSs and to transmit a balancing command based on the determination of whether to perform balancing to the second-level BMSs.

[0014] In another aspect of the present invention for solving the above-described problem, an energy storage system is proposed, comprising: a plurality of first-level BMS (Battery Management Systems) for monitoring first information related to balancing and second information related to an emergency situation of each of a plurality of vanadium ion battery cells or modules; a second-level BMS for transmitting report information or performing an emergency response control operation depending on whether information received from the plurality of first-level BMSs is the first information or the second information; and a third-level BMS configured to, when receiving the report information from the second-level BMSs, determine whether to perform balancing based on the report information, and transmit a balancing command according to the determination of whether to perform balancing to the second-level BMSs.

[0015] According to the embodiments of the present invention as described above, by processing voltage balancing-related operations and emergency response control operations separately, the burden on the second level BMS is reduced during voltage balancing operations, and at the same time, the second level BMS performs control operations on its own in emergency situations, thereby providing the advantage of being able to quickly respond to the situation.

[0016] In addition, by utilizing a multi-level BMS to efficiently perform voltage management and emergency response control of the ESS, it is possible to implement each control item efficiently while minimizing the increase in cost required for ESS implementation due to an increase in the number of BMS.

[0017] In addition, by specifying the type / requirements of the battery for implementing the above-described function, it is possible to perform voltage imbalance resolution and emergency situation control separately, and voltage imbalance can be quickly resolved through high-speed charging during balancing operation.

[0018] On the other hand, unlike LIBs, by applying batteries with a certain level of fire safety, even when a specific BMS signal is missing or the voltage of a specific cell is at a very low level close to 0V, the acquired BMS information can be used to maintain the charge and discharge of the corresponding cell or module in a predetermined cycle, thereby expanding the scope of ESS utilization to remote areas or difficult-to-access locations.

[0019] The effects that can be obtained from the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by a person having ordinary skill in the art to which the present invention belongs from the description below.

[0020] FIG. 1 is a drawing for explaining a battery type applied to ESS according to one embodiment of the present invention.

[0021] FIG. 2 is a drawing for explaining the structure of a VIB ESS according to one embodiment of the present invention.

[0022] FIG. 3 is a diagram for explaining a control mechanism of a multi-level BMS according to one embodiment of the present invention.

[0023] FIGS. 4 and 5 are drawings illustrating the structure of a VIB cell according to one embodiment of the present invention.

[0024] FIGS. 6 and 7 are drawings showing a laminated structure of a VIB module according to one embodiment of the present invention.

[0025] FIGS. 8 to 10 are drawings for explaining the installation of a VIB pack according to one embodiment of the present invention.

[0026] FIG. 11 is a drawing for explaining an operation method in a multi-level BMS according to one embodiment of the present invention.

[0027] FIG. 12 is a diagram for explaining a control operation from the perspective of a second level BMS according to one embodiment of the present invention.

[0028] FIG. 13 is a diagram for explaining an operation when a signal of a specific BMS is missing according to one embodiment of the present invention.

[0029] FIG. 14 is a drawing for explaining an operation when the voltage of a specific cell is below a predetermined level according to one embodiment of the present invention.

[0030] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein. In addition, in the drawings, parts irrelevant to the description have been omitted to clearly explain the present invention, and similar parts have been designated with similar reference numerals throughout the specification.

[0031] Throughout the specification, whenever a part is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise stated.

[0032] As described above, one aspect of the present invention proposes an ESS for implementing a method of efficiently distinguishing and processing voltage balancing-related operations and emergency response control operations.

[0033] To this end, we will first compare the characteristics of each battery type applied to ESS by comparing examples of the most popular LIB and the vanadium ion battery (VIB) proposed by the inventor of the present invention.

[0034]

[0035] ESS battery types

[0036] In the description of the embodiments described below, the battery used in the ESS need not be interpreted as being limited to a specific type. However, as described above, it is preferable to use a battery that provides conditions for performing voltage balancing-related operations and emergency response control operations separately in the ESS. To this end, a VIB-based ESS proposed by the applicant is described.

[0037]

[0038] FIG. 1 is a drawing for explaining a battery type applied to ESS according to one embodiment of the present invention.

[0039] There are various types of batteries applicable to ESS, for example, lead-acid batteries, lead carbon batteries, NAS (Sodium Sulfur) batteries, LIBs, flow batteries, etc. can be utilized. Fig. 1 (A) illustrates an example system in which a LIB ESS (210) is applied, in which LIBs, which are currently receiving the most attention among these various ESS batteries, are applied.

[0040] LIBs are attracting attention for their high energy and power densities, being approximately three times lighter than conventional lead-acid batteries, and their high power density, which allows for a 50-80% reduction in space consumption. Furthermore, they can discharge only 1-2% of their charge per month, maintaining a long service life. They are expected to last for approximately 10 years and, depending on conditions, have up to 5,000 battery cycles.

[0041] However, in the case of LIB, when operated as an ESS, charging and discharging are performed under the basic condition of 0.2 to 0.5 C, and when operated at a high C-rate, continuous operation is difficult due to heat generation, and there is a high risk of fire.

[0042] Additionally, for alkaline and lead batteries, it is common to operate at 0.05C (= 20 hours of discharge) to avoid battery capacity reduction (performance reduction) due to heat generation.

[0043] In contrast, the VIB developed by the present applicant refers to a secondary battery that electrochemically stores / releases energy using vanadium ions as an active material. While existing vanadium-based batteries store / release electrical energy by forcibly circulating / transporting / storing active materials participating in electrochemical reactions (e.g., vanadium ions, H+ cations, water, sulfuric acid, etc.) by an externally powered pump, the VIB uses the internal electric field, osmotic pressure, concentration difference, etc. of the active materials in the cell and / or module to change and move ions, and the active materials store / release energy through electrochemical reactions within the cell and / or module.

[0044] In particular, VIBs can be charged and discharged at rates of 0.5 to 5C (maximum 10C). Furthermore, because they operate using a water-soluble electrolyte, they are free from fire risks and offer the advantage of being able to utilize a wide range of SoCs.

[0045] Accordingly, Fig. 1 (B) illustrates a configuration in which a VIB ESS (140) using such VIB is applied according to one embodiment of the present invention.

[0046] For example, in the case of LIB, high output may cause heat generation and affect battery life, but in the case of VIB, stable high output is possible. In addition, in the case of LIB, there are limitations such as 1C charging and 1C discharging, but VIB can control input / output flow with high output, and for example, in the case of a power outage in the grid (110), the VIB ESS (140) can assist both the grid (110) and the charger with high output, so the use of VIB ESS (140) has the advantage of being able to perform very efficient ESS charge / discharge management.

[0047] In particular, since there is no risk of fire due to overload in the case of VIB, when such VIB is applied to the ESS of this embodiment, the system of the present invention can be preferably applied to various auxiliary facilities while ensuring safety, so it can be said to be a very effective power supply system. In addition, since the VIB ESS (140) enables safe and efficient energy supply, it can be utilized as a very effective, safe, and environmentally friendly energy supply means for energy conservation, energy environment, and realization of carbon neutrality.

[0048] Additionally, when utilizing the VIB ESS (140) as illustrated in (B) of FIG. 1, the high-speed charge / discharge performance of the VIB as described above can be utilized to more efficiently utilize the amount of power measured by multiple power meters (211, 212, 220). For example, when the measured value of the power meter (212) measuring the amount of power flowing into the charger decreases rapidly, this can be supported by high-speed discharge, and when the measured value of the power meter (220) measuring at the load end other than the ESS is below a predetermined standard, the VIB ESS (140) can be charged at high speed.

[0049] Meanwhile, LIBs have upper and lower voltage limits, so they use a relatively narrow voltage range (window). Specifically, when LIBs reach 0 V or a harsh discharge state (a state lower than the lower voltage limit), dendrites are generated, which can damage the separator, causing a short circuit and resulting in thermal runaway.

[0050] In contrast, VIB has an upper voltage limit but no lower voltage limit, allowing for a relatively wide voltage range (window) to be utilized. This means that even when the voltage reaches 0 V or the system is fully discharged, no particular issues arise, allowing for more flexible operation depending on the measurement conditions of multiple power meters.

[0051] In addition, in the case of LIB, there is a problem that capacity difference occurs during a certain cycle of operation due to the existence of irreversible reactions (surface precipitation phenomenon, solid electrolyte interphase phenomenon, cracking phenomenon) caused by phase change when repeating charge and discharge cycles, but in the case of VIB, there is an advantage that there is no difference in capacity between the initial capacity and the capacity after a certain cycle of operation by utilizing a reversible reaction.

[0052] Meanwhile, in connection with the upper / lower limit voltages as described above, in the case of LIB, it is impossible to use it below 20% of SoC in practice (theoretically), but in the case of VIB, since there is no lower limit voltage, it can be used below 20% of SoC in practice (theoretically).

[0053] Here, the term "actual (theoretical) SoC" is used to distinguish it from the SoC provided by the manufacturer. Manufacturers typically indicate the safe range of the actual SoC as 0% - 100% for safety reasons. In contrast, the term "actual (theoretical) SoC" refers to the SoC where a battery's full charge is calculated as 100% and a full discharge as 0%.

[0054] The main features of these LIBs and VIBs can be summarized as shown in [Table 1] below.

[0055] LIBVIB High fire risk None Charge / discharge rate 0.2-0.5 C 0.5 - 5 C (Max 10 C) Voltage range Upper and lower voltage limits exist Upper voltage limit exists, lower voltage limit is X Actual SoC less than 20% Not operable Possible Irreversible reaction due to change in characteristics when repeating cycles Reversible reaction

[0056]

[0057] FIG. 2 is a drawing for explaining the structure of a VIB ESS according to one embodiment of the present invention.

[0058] As shown in Fig. 2, VIB ESS also includes components such as a battery, BMS, PCS, and EMS.

[0059] Specifically, the battery can be configured from the smallest cell unit to a module in which 10-20 cells are grouped, multiple modules can configure a pack, and multiple packs can configure a system level. In response to this structure, the BMS can also have a hierarchical structure of a cell BMS (not shown), a module BMS (31; level 1), a pack BMS (32; level 2), and a system BMS (33; level 3).

[0060] Here, each level refers to an operation level that includes a different control configuration than the BMS described above. For example, Level 2 may specify control operations with the Level 1 control stage of the pack BMS (32) described above and control operations for the switch gear (34), and Level 3 may specify control operations between the system BMS (33) and the PMS (35) described above. In addition, the final Level 4 may specify control operations between multiple PMSs (35) and EMSs (36).

[0061] Here, the switch gear (34) can control the battery and power lines (contactor, precharge, fuse), and the linear IC (37) can perform switch (38) turn-on by receiving a command from the pack BMS (32). At this time, the switch turn-on may mean performing balancing by resistance, and the resistance here may be a pattern resistor in which copper wires are formed in a pattern on the board.

[0062]

[0063] Based on the above description, the following describes the control mechanism of a multi-level BMS according to embodiments of the present invention.

[0064] FIG. 3 is a diagram for explaining a control mechanism of a multi-level BMS according to one embodiment of the present invention.

[0065] The ESS according to the embodiment illustrated in FIG. 3 may first include a plurality of first-level BMSs (310a, …, 310l) that monitor voltage status information and temperature status information of each of a plurality of battery groups.

[0066] In the embodiments described in FIGS. 1 and 2, the type of battery applied to the ESS is exemplarily described as VIB (FIG. 1(B) and FIG. 2) in contrast to LIB (FIG. 1(A)). However, the type of battery applied to the ESS need not be limited to VIB. For example, the ESS in this specification may utilize a VRB (Vanadium Redox Battery), a PSB (polysulfide bromide battery), a ZBB (zinc-bromine battery), etc.

[0067] Under these assumptions, the battery group managed by the first level BMS (310) may correspond to a battery module unit as shown in FIGS. 1 and 2, or may be a battery group of a different unit. However, the embodiment illustrated in FIG. 3 illustrates a concept in which voltage status information and temperature status information are processed separately, and for this purpose, voltage status information is represented as first type information (A), and temperature status information is represented as second type information (B). However, the second type information (B) may represent not only temperature status information but also various information related to an emergency situation within the ESS (e.g., short circuit information, etc.).

[0068] The ESS of the embodiment illustrated in FIG. 3 may also include a second level BMS (320) configured to generate report information (R) based on voltage status information (A) received from the plurality of first level BMSs (310a, .., 310l) and to perform emergency response control (C2) operations based on the temperature status information (B). The second level BMS (320) may include a plurality of (320a, .., 320m) as illustrated in FIG. 3, and these (320a, .., 320m) may be controlled by the third level BMS (330). The third level BMS (330) may be configured to determine whether to perform balancing based on the report information (R) received from the second level BMS (320a, .., 320m), and transmit a balancing command (C1) based on the determination of whether to perform balancing to the second level BMS (320a, .., 320m).

[0069] As described above, in this embodiment, the second level BMS (320) distinguishes between the first type information (A) and the second type information (B) received from the first level BMS (310), and performs a balancing operation according to voltage imbalance for the first type information (A) according to the judgment of the third level BMS (330), but issues an emergency response control command (C2) on its own for the second type information (B) and performs an operation accordingly. At this time, the emergency response control operation may include a switching operation for power cutoff of a specific battery group among the plurality of battery groups.

[0070] Specifically, in a preferred embodiment of the present invention, based on the temperature status information, if there is a group among the plurality of battery groups whose temperature is higher than a first reference value (e.g., 35 °C), the second level BMS (320) may be configured to generate a warning as an emergency response control operation, and if there is a group among the plurality of battery groups whose temperature is higher than a second reference value (e.g., 40 °C) that is higher than the first reference value, the second level BMS (320) may be configured to perform a switching operation to cut off power to the corresponding battery group.

[0071] However, the second level BMS (320) according to the present embodiment is characterized by processing the first type information (A) and the second type information (B) separately, and accordingly, it is preferable that the second level BMS (320) not perform emergency response control (C2) based on the voltage status information (A).

[0072] In the case of ESS using batteries with a limited available voltage range, such as LIB, and a risk of fire, if a voltage imbalance occurs based on voltage status information (A), it may be desirable to regard this as an emergency situation with a risk of fire and perform a switching operation to cut off power to the corresponding battery cell or battery module.

[0073] However, in the case of an ESS using a battery having a wide usable voltage range and no threat of fire, such as the VIB described above, when a voltage imbalance occurs based on voltage status information (A), it is proposed to distinguish this from an emergency situation with a threat of fire, and to perform a switching operation to cut off the power of the corresponding battery cell or battery module in response to the emergency situation, but to perform a balancing operation through high-speed charging and discharging in the case of a voltage imbalance, and for this purpose, the second level BMS (320) can perform a balancing operation by pattern resistance by turning on the switch of a specific battery group or a specific battery cell among a plurality of battery groups.

[0074]

[0075] Meanwhile, the ESS using the VIB proposed by the inventor of the present invention has a characteristic that the load for the BMS to perform cell balancing is large compared to the ESS using the LIB. Accordingly, as explained through the embodiment illustrated in Fig. 3, the second level BMS (320) does not determine whether balancing is necessary on its own based on the voltage status information (A), but instead reports this to the third level BMS (330), and the balancing operation is performed according to the judgment of the third level BMS (330).

[0076] To explain this in detail, the structure of ESS including VIB is described in detail below.

[0077] FIGS. 4 and 5 are drawings illustrating the structure of a VIB cell according to one embodiment of the present invention.

[0078] A VIB cell (10) according to an embodiment of the present invention includes a frame (11), an anode (12), a cathode (13), a separator (19) separating the anode and the cathode, an anode current collector (14) electrically connected to the anode, and a cathode current collector (15) electrically connected to the cathode. The frame is divided into two spaces by the separator, and an anode and a cathode are accommodated in each space.

[0079] The anode (12) includes an electrolyte in which an anode redox couple is dissolved, and may further include a conductive material such as carbon felt. The anode redox couple may be implemented with a material including at least one of vanadium (V), zinc (Zn), bromine (Br), chromium (Cr), manganese (Mn), titanium (Ti), iron (Fe), cerium (Ce), and cobalt (Co), and in this embodiment, a V2+ / V3+ redox couple is assumed. The electrolyte may be an acidic aqueous solution that conducts current through ionization, and preferably includes sulfuric acid. In this embodiment, the electrolyte may be prepared by dissolving VOSO4 (vanadylsulfate) in H2SO4.

[0080] The cathode (13) includes an electrolyte in which a cathode redox couple is dissolved, and may further include a conductive material such as carbon felt. The cathode redox couple may be implemented with a material including at least one of vanadium (V), zinc (Zn), bromine (Br), chromium (Cr), manganese (Mn), titanium (Ti), iron (Fe), cerium (Ce), and cobalt (Co), and in this embodiment, a V4+ / V5+ redox couple is assumed. The electrolyte is preferably the same as the electrolyte of the anode.

[0081] The anode current collector (14) and the cathode current collector (15) can be made of a metal with high electrical conductivity, such as copper or aluminum, and allow current to flow during the charge and discharge process. A portion of the anode current collector (14) and the cathode current collector (15) can protrude from the frame (11) and be connected to a bus bar, which will be described later. A positive electrode plate (17) can be provided between the anode current collector (14) and the anode (12), and between the cathode current collector (15) and the cathode (13), and the positive electrode plate (17) prevents the current collectors (14, 15) from being oxidized. The positive electrode plate (17) can be formed by coating the current collectors (14, 15).

[0082] FIGS. 6 and 7 are drawings showing a laminated structure of a VIB module according to one embodiment of the present invention.

[0083] A VIB module (100) according to an embodiment of the present invention includes a plurality of VIB cells (10) that are stacked in one direction. An anode (12) of any one of the plurality of VIB cells (10) is stacked with an anode (12) of an adjacent VIB cell (10), and a cathode (13) of any one of the plurality of VIB cells (10) is stacked with a cathode (13) of an adjacent VIB cell (10). Therefore, the plurality of adjacent VIB cells (10) share one anode current collector (14) or cathode current collector (15). That is, a plurality of VIB cells (10) are stacked so that the anode (12) of the first VIB cell (10a) is adjacent to the anode (12) of the second VIB cell (10b) with the anode collector (14) interposed therebetween, and the cathode (13) of the second VIB cell (10b) is adjacent to the cathode (13) of the third VIB cell (10c) with the cathode collector (15) interposed therebetween.

[0084] The VIB module (100) has a rectangular shape that is elongated in the stacking direction of the VIB cells (10). The anode collector (14) and cathode collector (15) protruding from the frame can be connected to the positive bus bar or the negative bus bar.

[0085] FIGS. 8 to 10 are drawings for explaining the installation of a VIB pack according to one embodiment of the present invention.

[0086] As illustrated in FIG. 8, the VIB module (100) can be installed by inserting it into a VIB pack (1000). The VIB module (100) can be covered with a case as illustrated in FIG. 8, and the VIB module (100) can be installed using a forklift or lift.

[0087] Afterwards, as shown in Fig. 9, the sensing cable (181) and bus bar (110) of the BMS module (180) can be connected using special bolts and a wrench.

[0088] After connecting the sensing cable (181) and the bus bar (110), the VIB module (100) and the switch (1100) can be connected using the connecting bus bar (120) as shown in Fig. 10. At this time, care must be taken not to connect the negative pole to the positive pole connector or not to connect the positive pole to the negative pole connector.

[0089] It is desirable to ground the VIB pack (1000) to prevent electric shock due to leakage current. As illustrated in Fig. 10, the connection of modules can be maintained by the bus bar (110) and the connecting bus bar (120).

[0090] For VIBs with the structure described above, modules are initially connected in parallel, then connected in series. Consequently, the system current controlled by the BMS is relatively higher than that of LIBs, and consequently, the load required by the BMS for balancing is greater.

[0091]

[0092] Accordingly, in a preferred embodiment of the present invention, instead of determining a balancing operation according to voltage imbalance in the second level BMS (pack BMS in case of using VIB), the third level BMS (system BMS in case of using VIB) determines a balancing operation, and performs operations such as rapid charging using switching control and pattern resistance in the second level BMS (pack BMS). A control method according to this embodiment is described below with reference to FIG. 11.

[0093] FIG. 11 is a drawing for explaining an operation method in a multi-level BMS according to one embodiment of the present invention.

[0094] In the embodiment of FIG. 11, the first level (Level 1) controls 10-20 cells (180) and can be responsible for checking and transmitting cell data of serially connected cells (180). Specifically, the module BMS (170) monitors the battery cell status, which can include cell voltage measurement and module temperature measurement. In addition, as described below, the module BMS (170) can receive a balancing instruction (S1110) from the pack BMS (160) of the second level (Level 2) and perform a balancing operation through the switching (191) turn-on of the linear IC (190) and the pattern resistor (192).

[0095] Meanwhile, if the minimum voltage required for operating the module BMS (170) is not secured during the process of balancing operation as described above, the operation of the module BMS (170) may be limited, so that the minimum voltage (e.g., 3 V) required for operating the module BMS (170) may be secured by including a boost circuit (not shown).

[0096] In the embodiment of Fig. 11, the second level may be composed of a pack BMS (160) and a switch gear (161). The second level collects data from the first level and transmits the collected data to the third level. At this time, conventionally, the pack BMS (160) of the second level determines whether to perform balancing based on voltage status information received from the module BMS (170). However, in the present embodiment, the pack BMS (160) does not determine whether to perform balancing on its own, but reports this to the system BMS (130) of the third level, and when receiving a balancing command from the system BMS (130), it may be configured to control the linear IC (190) of the first level, etc., as described above.

[0097] However, as described above, the second level pack BMS (160) can be configured to control the switch gear (161) by itself in case of an emergency such as high temperature, unlike the voltage imbalance information, so as to isolate a specific battery module from the power source.

[0098] In addition, the pack BMS (160) can be configured to manage minimum and maximum voltages and identify cell addresses. It also performs the role of identifying the status of the lower-level serial system and manages the switching gear (161).

[0099] In addition, the pack BMS (160) has event management (e.g., communication error) and alarm performance functions, and can manage SOC (State of Charge) and DOD (Depth of Discharge).

[0100] In the embodiment of Fig. 11, the third level may include a configuration of a system BMS (150), a PCS (140), and a PMS (130). In this embodiment, the third level may be configured to determine whether balancing is performed and provide a command accordingly to the second level, and may also be configured to notify the fourth level of an abnormal state.

[0101] Additionally, as illustrated in FIG. 11, a plurality of third level systems may be included.

[0102] Specifically, the third level system BMS (150) can manage multiple strings (multiple enclosures). That is, the system BMS (150) can count the number of enclosures, determine the voltage of each enclosure, and receive temperature information for each, and details thereof can be reported from the pack BMS (160) (e.g., average temperature, maximum and minimum voltages, etc.).

[0103] In addition, the system BMS (150) can receive reports on the reasons for connection requests and connection request failures, and can receive reports on the cause of alarms. In addition, the system BMS (150) can perform activation and deactivation of each enclosure, and can also receive reports on the connection status of the PCS (140) and the switch gear (161).

[0104] In addition, the system BMS (150) according to the present embodiment can determine whether balancing is necessary for a specific cell, module, or pack based on voltage status information reported from the pack BMS (160), and can provide a balancing command to the pack BMS (160).

[0105] Meanwhile, the third level PMS (130) has a structure that receives reports from the PCS (140) and the system BMS (150), and specifically, when an alarm sounds, it can receive a report about it.

[0106] Additionally, PMS (130) has the authority to reset the alarm, and can identify this function on an enclosure basis, thereby turning on / off a specific enclosure.

[0107] In addition, PMS (130) can perform the function of transmitting necessary information to EMS (120).

[0108] That is, at the third level, the system BMS (150) performs battery-related control, and the PMS (130) can be seen as performing control of peripheral devices other than the battery in addition to battery-related functions.

[0109] In the embodiment of FIG. 11, the fourth level includes an EMS (120), which can calculate an ESS utilization strategy (e.g., operation connection / disconnection / precharge) after checking the status of the grid / load (110).

[0110] Specifically, EMS (120) performs management in bank units (1 PCS, 1 system BMS), and based on this, can transmit commands to PCS (140) through PMS (130).

[0111] Meanwhile, although not shown in FIG. 11, an ESS according to an embodiment of the present invention is proposed to additionally include a security means (e.g., a physical switch) for blocking or stopping the ESS in a domain separate from the network switch in case of unauthorized access, emergency, or abnormal state of the ESS.

[0112] In other words, abnormal states of ESS can be caused not only by emergency situations such as fire but also by intentional attacks such as unauthorized access, and to effectively block these, physical switches in a different domain separate from the network switch can be utilized.

[0113]

[0114] FIG. 12 is a diagram for explaining a control operation from the perspective of a second level BMS according to one embodiment of the present invention.

[0115] The second level BMS can receive first information related to balancing of each of a plurality of vanadium ion battery cells or modules and second information related to an emergency situation from the first level BMS (S1210).

[0116] The second level BMS according to the present embodiment proposes to process the first information and the second information by distinguishing them (S1220), transmit the first information as report information to the third level BMS (S1230), and when receiving a balancing command from the third level BMS (S1240), perform fast charging accordingly (S1250).

[0117] The speed of fast charging may vary depending on the type of battery used, but this embodiment proposes fast charging at a speed of 0.5 C-Rate or higher, which is faster than that of existing LIBs. Furthermore, when utilizing VIBs as described above, fast charging at a speed of up to 10 C-Rate is possible, and preferably, fast charging can be performed within the range of 0.5 to 5 C-Rate.

[0118] Meanwhile, the Level 2 BMS can independently determine whether an emergency situation exists based on secondary information related to the emergency situation (S1260). This secondary information can include not only temperature information, but also short-circuit information, damage information, and more. Unlike the voltage-related first information, the Level 2 BMS can independently determine the emergency situation, enabling a more rapid response.

[0119] If an emergency situation is determined, the Level 2 BMS can perform emergency response control actions, for example, by controlling the switch gear to isolate a specific battery configuration from the power source.

[0120]

[0121] Damage Tolerance

[0122] As described above, in one aspect of the present invention, an ESS for implementing a method of efficiently distinguishing and processing voltage balancing-related operations and emergency response control operations has been described.

[0123] Against the backdrop of the configuration of such an ESS, or as an implementation in another aspect of such an ESS, in another aspect of the present invention, by applying a battery (e.g., VIB) having a fire safety level higher than a certain level, unlike a LIB, an ESS with enhanced damage endurance is proposed that utilizes acquired BMS information to maintain charge and discharge of a corresponding cell or module for a predetermined cycle even when a specific BMS signal is missing or the voltage of a specific cell is at a very low level close to 0 V.

[0124] FIG. 13 is a diagram for explaining an operation when a signal of a specific BMS is missing according to one embodiment of the present invention.

[0125] As illustrated in FIG. 13, there may be a case where the first type information (A) and / or the second type information (B) described above is not received from a specific BMS (310l) among a plurality of first level BMSs (310a, ..., 310l; for example, module BMS) (S1310).

[0126] As described above, in the case of an ESS to which LIB is applied, it is common to configure the module / cell corresponding to a specific BMS (310l) to be cut off from power in order to prevent a fire risk to the corresponding module / cell when a signal is not received from a specific BMS (310l).

[0127] However, in one embodiment of the present invention, a battery having a fire safety level above a certain level (e.g., VIB) may be applied, and even in this case, the module / cell may be configured to maintain charge / discharge for a certain number of cycles (e.g., 5 cycles), and during this period, a necessary warning message may be displayed and / or an operation for necessary maintenance may be performed.

[0128] Specifically, as described above, when a signal is not received from a specific BMS (310l) (S1310), the second level BMS (320a; for example, pack BMS) can report the status information (for example, signal missing BMS information) of the specific BMS (310l) to the third level BMS (330; for example, system BMS) (S1320). In this case, the third level BMS (330) can be configured to determine whether an emergency situation has occurred based on voltage status information and / or temperature status information already received from the specific BMS (310l). That is, in this embodiment, unlike an ESS to which LIB is applied, rather than blocking a corresponding module or cell due to a signal missing from a specific BMS (310l) itself, it is characterized by specifically determining whether an emergency situation has occurred and responding based on information such as voltage / temperature already acquired from the specific BMS (310l).

[0129] If, based on information such as voltage / temperature acquired from a specific BMS (310l), it is determined that the signal omission of a specific BMS (310l) is due to an emergency situation such as fire / short circuit, controlling the corresponding cell or module to be cut off from power is similar to the case of LIB ESS.

[0130] However, when judging based on information such as voltage / temperature acquired from a specific BMS (310l), the signal omission of a specific BMS (310l) may not be due to a dangerous situation such as fire / short circuit, but may simply be due to wiring damage or communication failure of the BMS (310l). In such a case where it is judged that it is not an emergency situation, it is proposed to control the corresponding cell or module to maintain charging / discharging for a predetermined number of cycles or more.

[0131] In another embodiment of the present invention, as described above, the second level BMS (320a) may directly determine whether an emergency situation exists and operate to maintain charging and discharging for a predetermined number of cycles or more for the corresponding cell or module.

[0132] However, it is preferable that the judgment as described above be made by a third level BMS (330) having relatively good computing performance, and FIG. 13 illustrates a concept in which the second level BMS (320a) reports this to the third level BMS (330) (S1320) and receives a command related to maintaining charging and discharging from the third level BMS (330) and operates (S1330).

[0133]

[0134] FIG. 14 is a drawing for explaining an operation when the voltage of a specific cell is below a predetermined level according to one embodiment of the present invention.

[0135] A state may be reached where the voltage of a specific battery group or cell among multiple battery modules or cells is below a predetermined level close to 0 V, and FIG. 14 illustrates, as an example, a state where the voltage of cell X (1410) is discharged to 0 V.

[0136] As described above, in the case of an ESS using LIB, if there is a cell discharged to 0V, there is a risk of fire due to overheating caused by the cell, so it is common to configure the cell discharged to 0V or the module containing the cell to be cut off from the power source.

[0137] However, in one embodiment of the present invention, a battery having a fire safety level above a certain level (e.g., VIB) may be applied, and even in this case, the charging and discharging of the cell may be configured to be maintained for a certain number of cycles (e.g., 5 cycles), and during this period, a necessary warning message may be displayed and / or an operation for necessary maintenance may be performed.

[0138] Specifically, the situation (S1410) for the above-described cell X can be reported through the voltage-related first type information (A) reported by the corresponding first level BMS (310l) to the second level BMS (320a) (S1420).

[0139] In one embodiment of the present invention, the second level BMS (320a) that has received this determines whether an emergency situation exists based on the voltage / temperature status information previously received from the first level BMS (310l), and if it is determined that there is no emergency situation, the voltage of cell X (1410) may be ignored at 0 V and charging / discharging may be performed, and in some cases, cell X (1410) may be recharged and utilized.

[0140] However, similar to the embodiment described above with respect to FIG. 13, it is proposed that this judgment be made by the third level BMS (300) in consideration of computing performance, and accordingly, the second level BMS (320a) of the embodiment illustrated in FIG. 14 reports status information on cell X (1410) to the third level BMS (330) (S1430), and if the third level BMS (330) determines that it is not an emergency situation (S1440), it is proposed that it operates to maintain charging and discharging of cell X for a predetermined number of cycles or more.

[0141]

[0142] The detailed description of the preferred embodiments of the present invention disclosed above has been provided to enable those skilled in the art to implement and practice the present invention. While the above description has been made with reference to preferred embodiments of the present invention, those skilled in the art will appreciate that various modifications and variations can be made to the present invention without departing from the scope of the present invention. For example, those skilled in the art can utilize the individual components described in the above-described embodiments in combination with each other.

[0143] Accordingly, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0144]

[0145] As described above, the relevant contents have been described in the best form for carrying out the embodiments.

[0146]

[0147] An ESS including a multi-level BMS according to embodiments of the present invention as described above can be utilized in a form capable of storing / supplying energy according to grid conditions in various fields, including a rapid charging station for an electric-powered mobile device.

Claims

1. Multiple first-level BMS (Battery Management Systems) that monitor voltage status information and temperature status information of each of multiple battery groups; A second level BMS configured to generate report information based on the voltage status information received from the plurality of first level BMSs and to perform an emergency response control operation based on the temperature status information; and An energy storage system comprising a third level BMS configured to determine whether balancing is to be performed based on report information received from the second level BMS, and to transmit a balancing command based on the determination of whether balancing is to be performed to the second level BMS.

2. In paragraph 1, An energy storage system, wherein the above emergency response control operation includes a switching operation for power cutoff of a specific battery group among the plurality of battery groups.

3. In paragraph 2, Based on the above temperature status information, If there is a group among the plurality of battery groups whose temperature is higher than the first reference value, the second level BMS generates a warning as the emergency response control operation. An energy storage system, wherein, if there is a group among the plurality of battery groups whose temperature is higher than the second reference value, which is higher than the first reference value, the second level BMS performs a switching operation to cut off power to the corresponding battery group.

4. In paragraph 2, An energy storage system in which the second level BMS does not perform the emergency response control based on the voltage status information.

5. In paragraph 1, An energy storage system in which the second level BMS performs a balancing operation by pattern resistance by turning on a switch of a specific battery group or a specific battery cell among the plurality of battery groups upon receiving the balancing command from the third level BMS.

6. In paragraph 1, If the voltage status information and the temperature status information are not received from a specific BMS among the plurality of first level BMSs, the second level BMS reports the status information of the specific BMS to the third level BMS, An energy storage system in which the third level BMS is configured to determine whether an emergency situation has occurred based on the voltage status information and the temperature status information received from the specific BMS.

7. In paragraph 6, An energy storage system, wherein the third level BMS is configured to maintain charging and discharging of a battery group corresponding to the specific BMS for a predetermined cycle when it is determined that there is no emergency situation based on the voltage status information and the temperature status information received from the specific BMS.

8. In paragraph 7, An energy storage system in which the third level BMS is controlled to display a warning message related to the status of the specific BMS while charging and discharging of a battery group corresponding to the specific BMS is maintained.

9. In paragraph 1, When the voltage status information received from the first level BMS indicates that the voltage of a specific battery group or cell among the plurality of battery groups or cells is below a predetermined level, the second level BMS reports the status information of the specific battery group or cell to the third level BMS. An energy storage system, wherein the third level BMS is configured to determine whether an emergency situation has occurred based on the voltage status information and the temperature status information received from a specific first level BMS corresponding to the specific battery group or cell.

10. In paragraph 9, An energy storage system, wherein the third level BMS is configured to maintain charging and discharging of the specific battery group or cell for a predetermined cycle when it is determined that there is no emergency situation based on the voltage status information and the temperature status information previously received from the specific BMS.

11. In paragraph 10, An energy storage system in which the third level BMS is controlled to display a warning message related to the status of the specific BMS while charging and discharging of the specific battery group or cell is maintained.

12. In paragraph 1, An energy storage system, wherein the second level BMS is configured to charge or discharge a specific battery group among the plurality of battery groups at a charging / discharging speed higher than a predetermined standard upon receiving the balancing command from the third level BMS.

13. In paragraph 12, An energy storage system in which the above-mentioned standard is determined as a value of 0.5 C-Rate or higher.

14. In paragraph 1, The above 3rd level BMS transmits reporting information to the PMS (Power Management System) together with the PCS (Power Conversion System). An energy storage system in which the above PMS performs control over peripheral devices other than the battery of the energy storage system based on the above report information.

15. In paragraph 1, An energy storage system, further comprising a security means for blocking or stopping the energy storage system in a domain separate from the network switch in case of unauthorized access to the energy storage system, an emergency situation, or an abnormal state.

16. In paragraph 1, The above multiple battery groups are: An energy storage system comprising a type of battery that does not pose a fire risk even when the voltage status information indicates an imbalance exceeding a predetermined standard.

17. In paragraph 16, The above battery is an energy storage system including a vanadium ion battery (VIB).

18. In paragraph 1, The above multiple battery groups correspond to multiple battery modules, The above first level BMS corresponds to a module BMS, The above second level BMS corresponds to the pack BMS, The above third level BMS is an energy storage system corresponding to the system BMS.

19. A plurality of first level BMS (Battery Management Systems) monitoring first information related to balancing and second information related to emergency situations of each of a plurality of vanadium ion battery cells or modules; A second level BMS that transmits report information or performs emergency response control operations depending on whether the information received from the plurality of first level BMSs is the first information or the second information; and An energy storage system comprising a third level BMS configured to determine whether to perform balancing based on the report information when receiving the report information from the second level BMS, and to transmit a balancing command based on the determination of whether to perform balancing to the second level BMS.

20. In paragraph 19, An energy storage system, wherein the second information includes at least one of temperature information, short circuit information, and damage information.

21. In paragraph 19, The above second level BMS is, If there is a cell or module among the plurality of vanadium ion battery cells or modules whose temperature is higher than the first reference value, a warning is generated as the emergency response control operation, An energy storage system, wherein, when there is a cell or module among the plurality of vanadium ion battery cells or modules whose temperature is higher than a second reference value that is higher than the first reference value, a switching operation is performed to cut off power to the vanadium ion battery cell or module.

22. In paragraph 19, The above second level BMS is an energy storage system that processes the subjects performing the balancing-related operations and the emergency-related operations separately.

23. In paragraph 19, An energy storage system, wherein the third level BMS is configured to maintain charging and discharging of a battery group corresponding to a specific BMS for a predetermined cycle based on previously received information of the specific BMS, even when a signal from a specific BMS among the plurality of first level BMSs is missing.

24. In paragraph 19, An energy storage system in which the third level BMS is configured to maintain charging and discharging of a specific battery group or cell for a predetermined cycle based on previously received information of a specific BMS corresponding to the specific battery group or cell, even if the voltage of the specific battery group or cell among the plurality of battery groups or cells is below a predetermined level.

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