Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
  • H01M10/425—Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing
  • H01M10/4257—Smart batteries, e.g. electronic circuits inside the housing of the cells or batteries
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
  • H01M10/4207—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells for several batteries or cells simultaneously or sequentially
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
  • H01M10/425—Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
  • H01M10/48—Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte
  • H01M10/482—Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte for several batteries or cells simultaneously or sequentially
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
  • H01M10/425—Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing
  • H01M2010/4271—Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M10/00—Secondary cells; Manufacture thereof
  • H01M10/42—Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
  • H01M10/425—Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing
  • H01M2010/4278—Systems for data transfer from batteries, e.g. transfer of battery parameters to a controller, data transferred between battery controller and main controller
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
  • H01M2220/00—Batteries for particular applications
  • H01M2220/20—Batteries in motive systems, e.g. vehicle, ship, plane
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
  • Y02E60/10—Energy storage using batteries

Definitions

• the invention relates to a battery management system for monitoring and regulating the operation of a rechargeable battery having a plurality of electrically interconnected, each comprising at least one battery cell battery modules, wherein the battery management system comprises at least one control unit and at least one cell monitoring unit, and wherein the at least one cell monitoring unit formed is to receive data regarding at least one operating parameter of at least one battery cell, to detect the received data and to transmit the detected data to the at least one control unit.
• the present invention relates to a battery system having a plurality of electrically interconnected battery modules (3), each comprising at least one battery cell (2), and with a battery management system.
• Battery systems are used particularly in hybrid, plug-in hybrid and electric vehicles to provide the electrical energy required for operation.
• Rechargeable lithium-ion cells are used in particular as battery cells.
• Battery systems are known in which the battery cells connected in series to a battery are.
• battery systems are known which comprise a plurality of battery modules, wherein a battery module in each case has a plurality of battery cells connected in series and / or in parallel.
• battery systems are also known in which a plurality of battery modules are connected via so-called coupling units in series and / or parallel to a battery string, by means of the coupling units individual battery modules can be connected to the battery string and / or bypass individual battery modules and thus disconnected from the battery string can.
• Such interconnections of switchable or disconnectable battery modules are known under the terms battery direct converter (BDC, BDC: Battery Direct Converter) and battery direct inverter (BDI, BDI: Battery Direct Inverter).
• battery management systems BMS, BMS: Battery Management System
• Important functions of these battery management systems are a so-called battery state detection, which determines the current state of the battery cells of the battery system, the communication with other systems, in particular control systems of a vehicle, and / or the implementation of the thermal management of the battery cells.
• battery management systems have, in particular, at least one control unit and a plurality of cell monitoring units.
• the cell monitoring units are usually so-called cell supervision circuits, the operating parameters, in particular battery cell voltages, battery cell currents and / or battery cell temperatures, detect and transmit to the at least one control unit.
• Different ECU architectures are known for the battery management system, in particular an architecture with a central control unit unit (Central-BMS system) and an architecture with a distributed BMS control unit unit (distributed system with and without daisy chain).
• these architectures are the Data transmission paths in particular due to availability and security considerations hard-wired, so wired.
• a battery sensor for use in the abovementioned battery systems is also known, in which the data transmission takes place wirelessly in order to reduce the wiring effort.
• a major disadvantage of previously known in the art battery systems is that an occurrence of a fault in the battery system usually leads to a complete failure of the battery system.
• the control unit of the battery management system usually detects a fault and initiates, if necessary using a so-called Battery Disconnection Unit (BDU), a shutdown of the battery system, in particular by appropriate switch contactors of the battery system are controlled.
• BDU Battery Disconnection Unit
• a battery management system for monitoring and regulating the operation of a rechargeable battery, which has a plurality of electrically interconnected, each comprising at least one battery cell battery modules, proposed, wherein the battery management system comprises at least one control unit and at least one cell monitoring unit.
• the at least one cell monitoring unit is designed to receive data relating to at least one operating parameter from at least one battery cell, to record the received data and to transmit the acquired data to the at least one control unit.
• the at least one cell monitoring unit is designed to detect at least one fault event with respect to the at least one battery cell and to trigger a shutdown of the battery module comprising the at least one battery cell.
• Operating parameters of at least one battery cell are in particular the battery cell voltage and / or the Battehezelltemperatur the at least one battery cell.
• Data relating to at least one Bethebsparameters are in particular measured values with respect to at least one Bethebsparameters, that is, in particular measured values with respect to the battery cell voltage and / or measured values with respect to the battery cell temperature.
• each battery cell comprises at least one sensor, wherein the at least one sensor operating parameters of the battery cell, in particular the battery cell voltage and / or the battery cell temperature, measures.
• the measured values recorded by the at least one sensor are advantageously each transmitted to at least one cell monitoring unit as data relating to at least one operating parameter and detected by the at least one cell monitoring unit.
• the at least one cell monitoring unit is a so-called Cell Supervision Circuit (CSC) with extended functionality.
• CSC Cell Supervision Circuit
• the at least one cell monitoring unit is advantageously also designed to perform so-called cell balancing.
• the at least one control unit is a so-called Battery Control Unit (BCU).
• BCU Battery Control Unit
• the at least one control unit of the battery management system according to the invention is advantageously designed to evaluate received data, in particular received data with respect to at least one operating parameter of at least one battery cell using at least one algorithm.
• the at least one control unit unit is advantageously designed to control and / or regulate functions of a battery system as a function of the result of the data evaluation, in particular the temperature control of the battery cells of a battery system and / or further safety-related functions of a battery system.
• the at least one Control unit is designed to control contactors of the battery system to electrically decouple the battery of the battery system and thus, for example, to prevent overcharging a battery system.
• the at least one cell monitoring unit of the battery management system is designed to detect fault events with respect to at least one battery cell and trigger a shutdown of these at least one battery cell battery module, the at least one control unit is advantageously relieved.
• This advantageously reduces the susceptibility of the battery management system to errors.
• the number of errors due to an excessive data volume to be processed by the at least one control unit unit is reduced, as a result of which the battery management system advantageously operates more robustly.
• the at least one cell monitoring unit also provides for switching off individual battery modules, a battery system can advantageously continue to be operated in the event of a fault with the remaining battery modules. Although this system performance of a battery system is sometimes reduced, but complete failure is prevented vorteilhaflich note.
• Triggering a shutdown of the at least one battery cell comprehensive battery module by the at least one cell monitoring unit is in particular an active driving a switching unit for switching off the at least one battery cell comprehensive battery module by the at least one cell monitoring unit and / or transmitting at least one signal by the at least one cell monitoring unit to a control device of the battery system, wherein the control device initiates a shutdown of the battery module comprising at least one battery cell upon receipt of the at least one signal.
• the at least one cell monitoring unit is designed to trigger the deactivation of the battery module comprising the at least one battery cell upon detection of the at least one fault event.
• the detection of a fault event by the at least one cell monitoring unit triggers quasi triggering the switching off of the battery module comprising the at least one battery cell.
• the shutdown of the battery module concerned battery module is thus triggered advantageously. Damage to the battery system, in particular damage that would lead to a total failure of the battery system, thereby advantageously largely avoided.
• the at least one cell monitoring unit is designed to generate a shutdown signal for triggering a shutdown of the battery module comprising at least one battery cell.
• the at least one cell monitoring unit is advantageously designed to send the generated shutdown signal.
• the generation of a shutdown signal is triggered by the detection of a fault event by the at least one cell monitoring unit.
• the generated shutdown signal is advantageously sent by the cell monitoring unit to trigger the shutdown of the at least one battery module causing the failure event.
• the switch-off signal is sent from the at least one cell monitoring unit to a switching unit of the battery system, via which the affected battery module is electrically connected to the other battery modules of the battery system.
• the switching unit may be formed in particular by means of semiconductor switching elements, wherein the reception of the switch-off signal by the switching unit triggers a switching of the switching unit and the affected battery module is thus advantageously switched off by the battery system.
• the at least one cell monitoring unit is further configured to detect a non-receipt of data from the at least one battery cell as a fault event.
• a faulty communication connection between the at least one battery cell of a battery module and the at least one cell monitoring unit is recognized as a fault event.
• this prevents that a problem with the at least one battery cell remains undetected in the event of a disturbed communication connection.
• the robustness of the system is advantageously further increased.
• the at least one cell monitoring unit is designed to evaluate the acquired data using at least one algorithm.
• the at least one cell monitoring unit is designed to determine battery cell properties by evaluating the acquired data, in particular the state of charge of a battery cell (SOC, SOC: state of charge).
• SOC state of charge of a battery cell
• the at least one control unit of the battery management system is advantageously further relieved, whereby the error rate of the overall system advantageously further decreases.
• the at least one cell monitoring unit is designed to record the evaluated data as further data and to transmit the evaluated data as detected data to the at least one control unit.
• a state of charge of a battery cell (SOC) determined by the at least one cell monitoring unit can be transmitted to the at least one control unit by the cell monitoring unit.
• the at least one cell monitoring unit is also designed to detect the at least one fault event by evaluating the acquired data.
• the at least one cell monitoring unit for this purpose comprises a comparator unit, wherein the exceeding and / or undershooting of predefined limit values is detected as a fault event.
• an implausible value for a state of charge of a battery cell is detected as a fault event by the at least one cell monitoring unit.
• the number of detectable fault events is further increased by this embodiment and the operation of a battery system is further improved with regard to the availability when using a Battehemanagementsystenns invention.
• the at least one cell monitoring unit has a transmitting device for the wireless transmission of data.
• the at least one cell monitoring unit is in particular designed to wirelessly transmit acquired data and / or a generated shutdown signal by means of the transmitting device.
• the at least one cell monitoring unit has a receiving device for the wireless reception of data.
• Battery management system is provided that the transmission and / or reception of data between units of the battery management system is at least partially wireless.
• the wireless transmission of the data advantageously reduces the wiring complexity.
• the wireless transmission of data takes place by means of a radio technology.
• RFID radio-frequency identification
• a battery system with a plurality of electrically interconnected battery modules, each comprising at least one battery cell and proposed with a battery management system according to the invention, wherein a cell monitoring unit of the battery management system for receiving data relating to at least one operating parameter of at least one battery cell is assigned at least one battery cell of a battery module of the battery system.
• a cell monitoring unit of the battery management system respectively acquires the data relating to the at least one operating parameter from the battery cell assigned to the cell monitoring unit.
• the at least one battery cell has sensors for detecting operating parameters of at least one battery cell, in particular sensors for detecting a battery cell voltage and / or a battery cell temperature.
• the data detected by the sensors are advantageously transmitted via a communication link to the at least one cell monitoring unit, received by the at least one cell monitoring unit and detected by the at least one cell monitoring unit as data relating to at least one operating parameter.
• a plurality of battery cells of a battery module are assigned to a cell monitoring unit, in particular all battery cells of a battery module, wherein the battery management system has at least as many cell monitoring units as battery modules.
• the battery system comprises coupling units via which the battery modules of the battery system are electrically interconnected.
• the battery modules can be electrically switched on or disconnected electrically from the battery system by means of a coupling unit assigned to the respective battery module.
• the coupling unit is advantageously designed to electrically switch off the battery module from the battery system upon receipt of a switch-off signal, in particular in that the coupling unit electrically bridges the battery module by means of a corresponding switching operation.
• the battery system in this embodiment advantageously comprises a plurality of battery modules, which can advantageously be switched or bridged over the coupling units to a battery string.
• the battery modules of the battery system as a battery direct converter (BDC, BDC: Battery Direct Converter) or as a battery direct inverter (BDI, BDI: Battery Direct Inverter) interconnected.
• BDC Battery Direct Converter
• BDI Battery Direct Inverter
• the battery system can be operated in this configuration in case of failure of one or more battery modules with the remaining battery modules on.
• the battery modules of the battery system are advantageously either additively connected to the output voltage of the corresponding battery string or bridged in the corresponding battery string, so that the battery cells of this battery module provide no contribution to the output voltage of the corresponding battery string.
• the battery system has a signal transmission path between the one battery module
• Coupling unit and the at least one cell monitoring unit which is associated with the at least one battery cell of this battery module comprises.
• Cell monitoring unit generated shutdown signal can be sent via this signal transmission path to the coupling unit to trigger in this way, the shutdown of a battery module of the battery system.
• the signal transmission path is realized wirelessly, wherein the at least one cell monitoring unit advantageously has a transmitting device for wireless transmission of the switch-off signal and the respective coupling unit advantageously has a receiving device for wirelessly receiving a switch-off signal.
• the wiring complexity of the battery system is advantageously further reduced.
• FIG. 2 is a schematic representation of a block diagram of an exemplary embodiment of a battery system according to the invention.
• FIG. 3 shows a schematic diagram of a block diagram of a further exemplary embodiment of a battery system according to the invention.
• FIG. 4 shows a schematic illustration of an exemplary embodiment of a battery module of a battery system with a coupling unit assigned to the battery module.
• the battery management system 1 shows, in a greatly simplified illustration, a battery management system 1 for monitoring and regulating the operation of a rechargeable battery, which has a plurality of battery modules 3 which are electrically interconnected and each comprising at least one battery cell 2.
• the battery management system 1 comprises a control unit 4 and a plurality of cell monitoring units 5.
• the battery management system 1 comprises a further functional unit 6, which in the present case is designed to control and / or regulate the temperature control of the battery modules 3.
• the battery cells 2 each have sensors (not explicitly shown in FIG. 1) for measuring the battery cell voltage and the battery cell temperature. Via a signal transmission path 7, the measured values detected by the sensors are transmitted to the cell monitoring units 5.
• the cell monitoring units 5 take over in particular the tasks of so-called Cell Supervision Circuits (CSC).
• CSC Cell Supervision Circuits
• the cell monitoring units 5 are designed to carry out a so-called cell balancing.
• the cell monitoring units 5 are each designed to receive the measured values acquired by the sensors, to record the received data and to transmit the detected data via the signal transmission path 8 to the control unit 4.
• the cell monitoring units 5 are designed to detect a fault event with respect to the battery cell 2, to which the respective cell monitoring unit 5 is connected via the signal transmission path 7, and to trigger a shutdown of the battery module 3 comprising this battery cell 2.
• the cell monitoring units 5 are designed to detect a non-receipt of measured values from the respective battery cell 2 as a fault event. This means that even if there is a transmission error from a battery cell 2 to a cell monitoring unit 5, this is recognized as a fault event.
• the cell monitoring units 5 are advantageously designed to evaluate acquired data using an algorithm.
• the cell monitoring units 5 are designed to determine current characteristics of the respective battery cell 2, in particular to determine the state of charge (SOC) of a battery cell 2 and / or the so-called state of health (SOH) of a battery cell 2.
• SOC state of charge
• SOH state of health
• the cell monitoring units 5 are advantageously designed to detect an error event by evaluating acquired data.
• cell monitoring units in particular comprise a comparator unit (not explicitly shown in FIG. 1).
• the comparator unit By means of the comparator unit, detected and / or evaluated data are subjected to a threshold value comparison, wherein an exceeding and / or falling below a predefined threshold value is recognized by the cell monitoring units 5 as an error event as a function of the respective data.
• the transmission of data via the signal transmission paths 7, 8 takes place wirelessly in the illustrated embodiment, preferably in accordance with a radio transmission standard. As a result, the wiring effort is advantageously reduced.
• the cell monitoring units 5 communicate with the control unit in a star-shaped architecture.
• the following implementations of the signal transmission paths for the connection of the cell monitoring units 5 are provided in particular:
• the communication between the battery cells 2 / battery modules 3 and the cell monitoring units 5 is wireless.
• the cell monitoring units 5 are connected to the control unit 4 via a common wired bus. Or:
• the communication between the battery cells 2 / battery modules 3 and the cell monitoring units 5 is wireless.
• the cell monitoring units 5 are also connected in a so-called daisy chain wired to the control unit 4. Or:
• the communication between the battery cells 2 / battery modules 3 and the cell monitoring units 5 is wireless according to the daisy-chain principle.
• the cell monitoring units 5 are also connected by wire to the control unit 4. Or:
• the communication between the battery cells 2 / battery modules 3 and the cell monitoring units 5 is wireless.
• the cell monitoring units 5 are connected to each other wired together and wirelessly connected to the control unit 4. Or:
• the communication between the battery cells 2 / battery modules 3 and the cell monitoring units 5 is wireless according to the daisy-chain principle.
• the cell monitoring units 5 are also connected wirelessly to the control unit 4. 2 greatly simplifies an exemplary embodiment of a battery system having a plurality of battery modules 3 and a battery management system as a block diagram.
• the interconnection of the battery modules 3 takes place via coupling units 9 according to a direct battery converter.
• the battery modules 3 are connected together to form a battery string, wherein the battery modules 3 can be individually connected to the battery string by means of the coupling units 9 or disconnected from the battery string by bridging the respective battery module 3.
• a coupling unit 9 will be explained in more detail in connection with FIG.
• the battery management system comprises a central control unit 4 and a plurality of cell monitoring units 5, as explained in connection with FIG. 1.
• the cell monitoring units 5 are in particular designed to record and evaluate data relating to the battery cell voltage of a group 2 of battery cells 2.
• the cell monitoring units 5 are designed to detect an error event in the context of the data evaluation, for example an excessive battery cell voltage value.
• the cell monitoring units 5 are designed to detect a fault in the signal transmission path 7 between a group 2 of battery cells and the cell monitoring unit 5 as a fault event.
• the cell monitoring devices 5 are further configured to generate a shutdown signal and to send the shutdown signal via the signal transmission path 10 between the cell monitoring units 5 of a battery module 3 and the coupling unit 9 of this battery module to the coupling unit 9.
• the reception of the switch-off signal by the coupling unit 9 triggers a switching operation in the coupling unit 9, whereby the battery module 3 connected via the coupling unit 9 to the battery system is electrically bypassed and thereby disconnected from the battery system.
• the cell monitoring units 5 are designed in this way to trigger a shutdown of a battery module 3 of the battery system.
• the further battery modules 3 of the battery system are advantageously still available. The battery system is thus advantageously still available despite the occurrence of a fault event. Fig.
• FIG. 3 shows in a greatly simplified manner a Batte esystem, in which the interconnection of the battery modules 3 as a battery direct inverter (BDI) takes place.
• the battery modules 3 are, as explained in connection with the embodiment in Fig. 2, individually connectable to the battery system via coupling units 9 and individually switched off from the battery system, but in an expanded form.
• error events can also be detected by the cell monitoring units 5 in the embodiment shown in FIG. 3, whereby the battery module 3 comprising the battery cell causing the fault event is shut down by the cell monitoring units 5 upon detection of an error event trigger by the respective cell monitoring device 5 via the signal transmission path 10, the respective coupling unit 9 drives.
• the coupling unit 9 in FIG. 4 is realized with semiconductor circuit elements.
• a battery module 3 which comprises a plurality of battery cells 2, with other battery modules 3 (not shown in Fig. 4) to a battery or a battery string electrically interconnected.
• the normal state battery module 3 is connected to the battery system
• a flow of current through the upper circuit part of the coupling device 9 is made possible, so that the battery module 3 is integrated into the current path 11.
• the lower circuit part of the coupling device blocks (symbolically represented by the cross 1 1 ').
• a signal is sent via the signal transmission path 10 connected to the coupling device 9 by a cell monitoring device, whereby the upper circuit part of the coupling unit 9 blocks by receiving the signal (symbolically represented by the dashed cross 12 ') and a new current path 12 is formed over the lower circuit portion of the coupling unit 9 and thus electrically bypasses the battery module 3.
• the exemplary embodiments illustrated in the figures and explained in connection therewith serve to explain the invention and are not restrictive of it.

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• Engineering & Computer Science (AREA)
• Manufacturing & Machinery (AREA)
• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Electrochemistry (AREA)
• General Chemical & Material Sciences (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Charge And Discharge Circuits For Batteries Or The Like (AREA)
• Secondary Cells (AREA)

Applications Claiming Priority (2)

Publications (1)

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• 2013
  • 2013-10-14 DE DE201310220684 patent/DE102013220684A1/de active Pending
• 2014
  • 2014-09-30 WO PCT/EP2014/070849 patent/WO2015055415A1/de active Application Filing
  • 2014-09-30 US US15/029,158 patent/US20160240894A1/en not_active Abandoned
  • 2014-09-30 EP EP14777318.8A patent/EP3058616A1/de not_active Withdrawn
  • 2014-09-30 CN CN201480056263.2A patent/CN105637697A/zh active Pending

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