CN111572405A - Active equalization system and method for lithium battery - Google Patents
Active equalization system and method for lithium battery Download PDFInfo
- Publication number
- CN111572405A CN111572405A CN202010442851.7A CN202010442851A CN111572405A CN 111572405 A CN111572405 A CN 111572405A CN 202010442851 A CN202010442851 A CN 202010442851A CN 111572405 A CN111572405 A CN 111572405A
- Authority
- CN
- China
- Prior art keywords
- battery
- voltage
- module
- single chip
- battery pack
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
- B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
- B60L58/18—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries of two or more battery modules
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
- B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
- B60L58/18—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries of two or more battery modules
- B60L58/20—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries of two or more battery modules having different nominal voltages
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
- B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
- B60L58/18—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries of two or more battery modules
- B60L58/22—Balancing the charge of battery modules
-
- 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
- H01M10/44—Methods for charging or discharging
- H01M10/441—Methods for charging or discharging for several batteries or cells simultaneously or sequentially
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L2240/00—Control parameters of input or output; Target parameters
- B60L2240/40—Drive Train control parameters
- B60L2240/54—Drive Train control parameters related to batteries
- B60L2240/545—Temperature
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L2240/00—Control parameters of input or output; Target parameters
- B60L2240/40—Drive Train control parameters
- B60L2240/54—Drive Train control parameters related to batteries
- B60L2240/547—Voltage
-
- 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
-
- 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
-
- 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
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/60—Other road transportation technologies with climate change mitigation effect
- Y02T10/70—Energy storage systems for electromobility, e.g. batteries
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Power Engineering (AREA)
- Transportation (AREA)
- Mechanical Engineering (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Secondary Cells (AREA)
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
Abstract
The invention discloses a lithium battery active equalization system and a method, wherein a plurality of batteries form a battery pack unit, a bidirectional DC/DC module charges or discharges a monomer with larger pressure difference, the working state of each DC/DC module is controllable, the DC/DC module has independent circuit and high reliability, and the complexity of the system is reduced; the DC/DC module is connected with the battery pack monomers through the switch array, only one of the monomers is balanced at the same time, mutual influence among circuits is avoided, charging current is applied to the battery according to the voltage difference between the voltage value of the battery monomer and the set voltage, the maximum monomer charging current can reach 3-4A, the balancing speed is high, and the voltage of the battery monomer in each group unit is close to the same voltage; the system has larger charging and discharging current, eliminates the pressure difference between the monomers, completes the balance maintenance of the battery, and is widely applied to the fields of new energy automobile battery balance systems, second-hand battery balance system transformation and power grid energy storage lithium battery application.
Description
Technical Field
The invention relates to an automobile battery equalization system, in particular to an active equalization system and method for a lithium battery, and belongs to the technical field of automobiles.
Background
In practical application, due to the fact that battery production materials have small differences in performance of battery monomers caused by different batches or due to factors such as defects in production process, consistency of a certain single battery in a battery pack is poor, pressure difference between the battery monomers is increased, overall capacity of the whole battery pack is reduced, and service life of the battery pack is seriously affected.
The existing solution usually adopts a balancing technical means to relieve the consistency problem of the battery, the existing lithium battery balancing technology is divided into an active balancing mode and a passive balancing mode, the passive balancing mode has small balancing current, the balancing current can only reach dozens of milliamperes, only a monomer with high battery voltage can be discharged, and when the capacity of a battery pack is large, the application effect is difficult to play; the active equalization mode is complex in control circuit, a plurality of power supply conversion circuits need to be added, most of the power supply conversion circuits can only perform one-way equalization, the circuit cost is high, and the like, so that the mass application of the active equalization mode is limited.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide an active equalization system and method for a lithium battery, wherein a battery pack is divided into a plurality of pack units, when a battery management system works, the voltage of each pack unit is independently detected through a voltage sampling circuit, a battery cell with larger voltage difference is found according to the maximum voltage difference of the battery cells in the pack unit and is compared with an average voltage or a reference voltage, when the battery cell is lower than the average voltage or the reference voltage, a single-chip IO port controls a DC/DC module to work in a positive working state, a corresponding control signal Ax in a switch array of the pack is in a high level, when a switch Ax is in the high level, effect tubes SxA and SxB are respectively controlled to be simultaneously connected through an isolation driving circuit, and at the moment, 5V direct-current voltage generated by a DC/DC module VO is applied to the battery cell BTx through switches SxA and SxB, charging the battery monomer; when the single battery is higher than the average voltage or the reference voltage, the IO port of the single chip controls the DC/DC module to work in a reverse working state, the corresponding control signal Ax in the switch array of the group is at a high level, after the switch Ax is at the high level, the isolation driving circuit controls the effect tubes SxA and SxB to be turned on simultaneously, at this time, the voltage on the single battery applies VO and 0V ends of the DC/DC module through the switches SxA and SxB, the DC/DC module generates 26.4V direct-current voltage through conversion, and the voltage is applied to the first battery pack and the second battery pack to reversely charge the battery packs.
The purpose of the invention can be realized by the following technical scheme:
the utility model provides a lithium cell initiative equalizing system, includes singlechip, CAN interface, a plurality of two-way DC/DC, a plurality of switch array and a plurality of group battery, singlechip and the two-way data connection of CAN interface, the CAN interface is used for sending voltage information, receives the work order that charges, and is a plurality of two-way DC/DC and a plurality of switch array electric connection, it is a plurality of switch array and a plurality of group battery electric connection, it is a plurality of switch array and singlechip electric connection, it is a plurality of two-way DC/DC and a plurality of group battery electric connection.
Furthermore, the bidirectional DC/DC is wide-voltage input, the bidirectional charging power supply module is isolated and output, and the DC/DC module can be set to be in a forward working state and a reverse working state according to external pin control; during forward work, Vin is a power input end, Vo is a power output end, during reverse work, Vo is a power input end, Vin is a power output end, the equalization system determines DC/DC forward work or reverse work according to a detected voltage value of a battery monomer, during forward work, the battery group system charges the battery monomer, a DC/DC module working power source is from a series voltage of the battery group 1 and the battery group 2, during reverse work, the battery monomer discharges to the battery group system, the DC/DC module working power source is from the battery monomer, and voltage generated between the DC/DC Vin and GND charges the battery group 1 and the battery group 2.
Further, the battery pack 1 and the battery pack 2 are formed by connecting 4 single batteries in series, the two battery packs are connected in series to form a voltage of about 26.4V to provide a working power supply for the DC/DC module, and simultaneously the battery pack 1 and the battery pack 2 are connected in series with other battery packs at a front stage and a rear stage again to provide a working power supply for the power battery system.
Further, the CAN interface is connected with a battery management system host through a single chip microcomputer and sends voltage, temperature signals and a balance state acquired by the single chip microcomputer to the battery management system host; the working state of the equalization system is controlled by a command of the battery management system host, when the single chip receives a balancing stopping command of the battery management system host through the CAN interface, the switch arrays are all closed, and the DC/DC module stops working until the equalization system starts working after receiving the balancing command again.
Furthermore, the switch array 1 and the switch array 2 respectively comprise 4 pairs of N-channel field effect transistors S1B, S2B, S3B and S4B, and P-channel field effect transistors S1A, S2A, S3A and S4A, are driven by a single chip microcomputer in an isolated mode and are turned on in pairs, only one of the N-channel field effect transistors and one of the P-channel field effect transistors are turned on in the S1-S4 field effect transistors at the same time, and the other three pairs of N-channel field effect transistors and the other three pairs of P-channel field effect transistors are all in a turned-off state.
Further, a method of an active equalization system of a lithium battery includes the following steps:
the method comprises the following steps: when the balance maintenance system is connected to the battery pack, the battery pack 1 and the battery pack 2 are connected in series to form about 26.4V voltage to provide a working power supply for the DC/DC module, and the single chip microcomputer acquires the voltage and the temperature of the battery pack in real time through the voltage and temperature sampling circuit and compares the acquired voltage with the balance set voltage set by the system;
step two: when the single chip microcomputer collects that the voltage of a certain battery monomer is lower than a set voltage value, and after a start balancing instruction sent by a battery management system is received through a CAN bus, a DC/DC module is controlled to work in a forward working state through an IO port of the single chip microcomputer, a corresponding control signal Ax in a switch array is in a high level, when the switch Ax is in the high level, effect tubes SxA and SxB are controlled to be simultaneously switched on through an isolation driving circuit respectively, at the moment, 5V direct-current voltage generated by a DC/DC module VO is applied to the battery monomer BTx through switches SxA and SxB to charge the battery monomer BTx, and at the moment, other three pairs of field effect tubes in the switch array are in a closed state;
step three: when the single chip microcomputer collects that the voltage of a certain single battery is higher than a set voltage value, and after a start equalization instruction sent by a battery management system is received through a CAN bus, the DC/DC module is controlled to work in a reverse working state through an IO port of the single chip microcomputer, a corresponding control signal Ax in the switch array is in a high level, when the switch Ax is in the high level, the effect tubes SxA and SxB are controlled to be simultaneously switched on through an isolation driving circuit, at the moment, the voltage on the single battery is applied to a VO end of the DC/DC module through switches SxA and SxB, the VO is input through the DC/DC module VO, direct-current voltage of about 26.4V generated at Vin and GND ends is applied to the battery pack 1 and the battery pack 2 to reversely charge the battery pack, and at the moment, other three pairs of field effect tubes in the switch array are in;
step four: when the balancing system works, the single chip microcomputer sends the working state of each path of balancing unit to the battery management system host through the CAN bus in real time, when the voltage difference between the single voltage value detected by the single chip microcomputer and the set voltage is reduced to the set voltage value, the battery management system host sends a balancing stopping instruction, after the single chip microcomputer receives the information, the Ax outputs a level signal, the switch tubes SxA and SxB are closed, meanwhile, a high level signal is given to an EN pin of the DC/DC module, and the output of the DC/DC module is closed.
Compared with the prior art, the invention has the beneficial effects that:
1. the equalization system of the invention combines a plurality of batteries into a battery pack unit, each battery pack unit comprises 2-4 battery monomers, a bidirectional DC/DC module is used for charging or discharging the monomer with larger differential pressure, the working state of each DC/DC module is controllable, the DC/DC module can also work in the charging or discharging state, the DC/DC module has independent circuits and high reliability, and the complexity of the system is reduced;
2. the DC/DC module is connected with the battery pack monomers through a switch array (field effect transistor), only one of the monomers is balanced at the same time, mutual influence between circuits is avoided, meanwhile, charging current is applied to the battery according to the voltage difference between the voltage value of the battery monomer and the set voltage, and the maximum monomer charging current can reach 3-4A, so that the balancing speed is high, and the voltage of the battery monomer in each pack unit can be enabled to be close to the same rapidly;
3. compared with the existing active equalization mode, the system has larger charging and discharging current, can quickly eliminate the pressure difference between the monomers, completes the equalization maintenance of the battery, and can be widely applied to the application fields of lithium batteries such as new energy automobile battery equalization systems, second-hand battery equalization system transformation, or power grid energy storage and the like.
Drawings
In order to facilitate understanding for those skilled in the art, the present invention will be further described with reference to the accompanying drawings.
FIG. 1 is a system diagram of an active equalization system and method for lithium batteries according to the present invention;
FIG. 2 is a schematic diagram of a battery grouping unit of the active equalization system and method for lithium batteries according to the present invention;
fig. 3 is a schematic diagram of a charge and discharge unit of the active equalization system and method for a lithium battery according to the present invention.
Fig. 4 is a schematic diagram of a bidirectional DC/DC charging and discharging unit of the active equalization system and method for a lithium battery of the present invention.
Detailed Description
The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1 to 4, an active equalization system for a lithium battery includes a single chip, a CAN interface, a plurality of bidirectional DC/DCs, a plurality of switch arrays, and a plurality of battery packs, wherein the single chip is in bidirectional data connection with the CAN interface, the CAN interface is used for sending voltage information and receiving a charging operation instruction, the plurality of bidirectional DC/DCs are electrically connected to the plurality of switch arrays, the plurality of switch arrays are electrically connected to the plurality of battery packs, the plurality of switch arrays are electrically connected to the single chip, and the plurality of bidirectional DC/DCs are electrically connected to the plurality of battery packs.
The bidirectional DC/DC is wide-voltage input, the bidirectional charging power supply module is isolated and output, and the DC/DC module can be set to be in a forward working state and a reverse working state according to external pin control; during forward work, Vin is a power input end, Vo is a power output end, during reverse work, Vo is a power input end, Vin is a power output end, the equalization system determines DC/DC forward work or reverse work according to a detected voltage value of a battery monomer, during forward work, the battery group system charges the battery monomer, a DC/DC module working power source is from a series voltage of the battery group 1 and the battery group 2, during reverse work, the battery monomer discharges to the battery group system, the DC/DC module working power source is from the battery monomer, and voltage generated between the DC/DC Vin and GND charges the battery group 1 and the battery group 2.
The battery pack 1 and the battery pack 2 are formed by connecting 4 battery monomers in series, the two battery packs are connected in series to form a voltage of about 26.4V and provide a working power supply for the DC/DC module, and meanwhile, the battery pack 1 and the battery pack 2 are connected in series with other battery packs at a front stage and a rear stage again and provide a working power supply for the power battery system.
The CAN interface is connected with the battery management system host through the singlechip and sends voltage, temperature signals and equilibrium state collected by the singlechip to the battery management system host; the working state of the equalization system is controlled by a command of the battery management system host, when the single chip receives a balancing stopping command of the battery management system host through the CAN interface, the switch arrays are all closed, and the DC/DC module stops working until the equalization system starts working after receiving the balancing command again.
The switch array 1 and the switch array 2 respectively comprise 4 pairs of N-channel field effect transistors S1B, S2B, S3B and S4B and P-channel field effect transistors S1A, S2A, S3A and S4A, are driven in a single-chip microcomputer isolation mode and are started in pairs, only one path of N-channel field effect transistor and one path of P-channel field effect transistor are started in the S1-S4 field effect transistors at the same time, and the other three pairs of N-channel field effect transistors and the other three pairs of P-channel field effect transistors are all in a closed state.
The method for the active equalization system of the lithium battery comprises the following steps:
the method comprises the following steps: when the balance maintenance system is connected to the battery pack, the battery pack 1 and the battery pack 2 are connected in series to form about 26.4V voltage to provide a working power supply for the DC/DC module, and the single chip microcomputer acquires the voltage and the temperature of the battery pack in real time through the voltage and temperature sampling circuit and compares the acquired voltage with the balance set voltage set by the system;
step two: when the single chip microcomputer collects that the voltage of a certain battery monomer is lower than a set voltage value, and after a start balancing instruction sent by a battery management system is received through a CAN bus, a DC/DC module is controlled to work in a forward working state through an IO port of the single chip microcomputer, a corresponding control signal Ax in a switch array is in a high level, when the switch Ax is in the high level, effect tubes SxA and SxB are controlled to be simultaneously switched on through an isolation driving circuit respectively, at the moment, 5V direct-current voltage generated by a DC/DC module VO is applied to the battery monomer BTx through switches SxA and SxB to charge the battery monomer BTx, and at the moment, other three pairs of field effect tubes in the switch array are in a closed state;
step three: when the single chip microcomputer collects that the voltage of a certain single battery is higher than a set voltage value, and after a start equalization instruction sent by a battery management system is received through a CAN bus, the DC/DC module is controlled to work in a reverse working state through an IO port of the single chip microcomputer, a corresponding control signal Ax in the switch array is in a high level, when the switch Ax is in the high level, the effect tubes SxA and SxB are controlled to be simultaneously switched on through an isolation driving circuit, at the moment, the voltage on the single battery is applied to a VO end of the DC/DC module through switches SxA and SxB, the VO is input through the DC/DC module VO, direct-current voltage of about 26.4V generated at Vin and GND ends is applied to the battery pack 1 and the battery pack 2 to reversely charge the battery pack, and at the moment, other three pairs of field effect tubes in the switch array are in;
step four: when the balancing system works, the single chip microcomputer sends the working state of each path of balancing unit to the battery management system host through the CAN bus in real time, when the voltage difference between the single voltage value detected by the single chip microcomputer and the set voltage is reduced to the set voltage value, the battery management system host sends a balancing stopping instruction, after the single chip microcomputer receives the information, the Ax outputs a level signal, the switch tubes SxA and SxB are closed, meanwhile, a high level signal is given to an EN pin of the DC/DC module, and the output of the DC/DC module is closed.
Compared with the prior art, the invention has the beneficial effects that:
1. the equalization system of the invention combines a plurality of batteries into a battery pack unit, each battery pack unit comprises 2-4 battery monomers, a bidirectional DC/DC module is used for charging or discharging the monomer with larger differential pressure, the working state of each DC/DC module is controllable, the DC/DC module can also work in the charging or discharging state, the DC/DC module has independent circuits and high reliability, and the complexity of the system is reduced;
2. the DC/DC module is connected with the battery pack monomers through a switch array (field effect transistor), only one of the monomers is balanced at the same time, mutual influence between circuits is avoided, meanwhile, charging current is applied to the battery according to the voltage difference between the voltage value of the battery monomer and the set voltage, and the maximum monomer charging current can reach 3-4A, so that the balancing speed is high, and the voltage of the battery monomer in each pack unit can be enabled to be close to the same rapidly;
3. compared with the existing active equalization mode, the system has larger charging and discharging current, can quickly eliminate the pressure difference between the monomers, completes the equalization maintenance of the battery, and can be widely applied to the application fields of lithium batteries such as new energy automobile battery equalization systems, second-hand battery equalization system transformation, or power grid energy storage and the like.
A lithium battery active equalization system, while working, after the equalization maintenance system inserts the assembled battery, the assembled battery 1 and assembled battery 2 are connected in series and formed about 26.4V voltage, provide the working power for DC/DC module, the voltage and temperature of the assembled battery of real-time acquisition of the one-chip computer through the voltage, temperature sampling circuit, and compare the voltage gathered with balanced set voltage that the system sets up;
when the single chip microcomputer collects that the voltage of a certain battery monomer is lower than a set voltage value, and after a start balancing instruction sent by a battery management system is received through a CAN bus, a DC/DC module is controlled to work in a forward working state through an IO port of the single chip microcomputer, a corresponding control signal Ax in a switch array is in a high level, when the switch Ax is in the high level, effect tubes SxA and SxB are controlled to be simultaneously switched on through an isolation driving circuit respectively, at the moment, 5V direct-current voltage generated by a DC/DC module VO is applied to the battery monomer BTx through switches SxA and SxB to charge the battery monomer BTx, and at the moment, other three pairs of field effect tubes in the switch array are in a closed state;
when the single chip microcomputer collects that the voltage of a certain single battery is higher than a set voltage value, and after a start equalization instruction sent by a battery management system is received through a CAN bus, the DC/DC module is controlled to work in a reverse working state through an IO port of the single chip microcomputer, a corresponding control signal Ax in the switch array is in a high level, when the switch Ax is in the high level, the effect tubes SxA and SxB are controlled to be simultaneously switched on through an isolation driving circuit, at the moment, the voltage on the single battery is applied to a VO end of the DC/DC module through switches SxA and SxB, the VO is input through the DC/DC module VO, direct-current voltage of about 26.4V generated at Vin and GND ends is applied to the battery pack 1 and the battery pack 2 to reversely charge the battery pack, and at the moment, other three pairs of field effect tubes in the switch array are in;
when the balancing system works, the single chip microcomputer sends the working state of each path of balancing unit to the battery management system host through the CAN bus in real time, when the voltage difference between the single voltage value detected by the single chip microcomputer and the set voltage is reduced to the set voltage value, the battery management system host sends a balancing stopping instruction, after the single chip microcomputer receives the information, the Ax outputs a level signal, the switch tubes SxA and SxB are closed, meanwhile, a high level signal is given to an EN pin of the DC/DC module, and the output of the DC/DC module is closed.
The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not intended to be exhaustive or to limit the invention to the precise forms disclosed. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. The invention is limited only by the claims and their full scope and equivalents.
Claims (6)
1. The utility model provides a lithium cell initiative equalizing system, its characterized in that includes singlechip, CAN interface, a plurality of two-way DC/DC, a plurality of switch array and a plurality of group battery, singlechip and the two-way data connection of CAN interface, the CAN interface is used for sending voltage information, receives the work order that charges, and is a plurality of two-way DC/DC and a plurality of switch array electric connection, it is a plurality of switch array and a plurality of group battery electric connection, it is a plurality of switch array and singlechip electric connection, it is a plurality of two-way DC/DC and a plurality of group battery electric connection.
2. The active equalization system for lithium batteries according to claim 1, wherein the bidirectional DC/DC is a wide voltage input, isolated output bidirectional charging power module, and the DC/DC module can be set to a forward working state and a reverse working state according to an external pin control; during forward work, Vin is a power input end, Vo is a power output end, during reverse work, Vo is a power input end, Vin is a power output end, the equalization system determines DC/DC forward work or reverse work according to a detected voltage value of a battery monomer, during forward work, the battery group system charges the battery monomer, a DC/DC module working power source is from a series voltage of the battery group 1 and the battery group 2, during reverse work, the battery monomer discharges to the battery group system, the DC/DC module working power source is from the battery monomer, and voltage generated between the DC/DC Vin and GND charges the battery group 1 and the battery group 2.
3. The active equalization system for lithium batteries according to claim 2, wherein each of the battery pack 1 and the battery pack 2 is formed by connecting 4 battery cells in series, and the two battery packs are connected in series to form a voltage of about 26.4V to provide working power for the DC/DC module, and simultaneously, the battery pack 1 and the battery pack 2 are connected in series with other battery packs at the front stage and the rear stage again to provide working power for the power battery system.
4. The active lithium battery equalization system of claim 1, wherein the CAN interface is connected to the battery management system host through a single chip, and sends the voltage, temperature signals, and equalization status collected by the single chip to the battery management system host; the working state of the equalization system is controlled by a command of the battery management system host, when the single chip receives a balancing stopping command of the battery management system host through the CAN interface, the switch arrays are all closed, and the DC/DC module stops working until the equalization system starts working after receiving the balancing command again.
5. The active equalization system and method for lithium batteries according to claim 1, wherein the switch array 1 and the switch array 2 are respectively composed of 4 pairs of N-channel fets S1B, S2B, S3B, S4B and P-channel fets S1A, S2A, S3A, and S4A, and are driven by a single chip microcomputer in an isolated manner to be turned on in pairs, only one of the N-channel and P-channel fets is turned on in S1-S4 fets at the same time, and the other three pairs of N-channel and P-channel fets are all in a turned-off state.
6. A method for an active equalization system of a lithium battery is characterized by comprising the following steps:
the method comprises the following steps: when the balance maintenance system is connected to the battery pack, the battery pack 1 and the battery pack 2 are connected in series to form about 26.4V voltage to provide a working power supply for the DC/DC module, and the single chip microcomputer acquires the voltage and the temperature of the battery pack in real time through the voltage and temperature sampling circuit and compares the acquired voltage with the balance set voltage set by the system;
step two: when the single chip microcomputer collects that the voltage of a certain battery monomer is lower than a set voltage value, and after a start balancing instruction sent by a battery management system is received through a CAN bus, a DC/DC module is controlled to work in a forward working state through an IO port of the single chip microcomputer, a corresponding control signal Ax in a switch array is in a high level, when the switch Ax is in the high level, effect tubes SxA and SxB are controlled to be simultaneously switched on through an isolation driving circuit respectively, at the moment, 5V direct-current voltage generated by a DC/DC module VO is applied to the battery monomer BTx through switches SxA and SxB to charge the battery monomer BTx, and at the moment, other three pairs of field effect tubes in the switch array are in a closed state;
step three: when the single chip microcomputer collects that the voltage of a certain single battery is higher than a set voltage value, and after a start equalization instruction sent by a battery management system is received through a CAN bus, the DC/DC module is controlled to work in a reverse working state through an IO port of the single chip microcomputer, a corresponding control signal Ax in the switch array is in a high level, when the switch Ax is in the high level, the effect tubes SxA and SxB are controlled to be simultaneously switched on through an isolation driving circuit, at the moment, the voltage on the single battery is applied to a VO end of the DC/DC module through switches SxA and SxB, the VO is input through the DC/DC module VO, direct-current voltage of about 26.4V generated at Vin and GND ends is applied to the battery pack 1 and the battery pack 2 to reversely charge the battery pack, and at the moment, other three pairs of field effect tubes in the switch array are in;
step four: when the balancing system works, the single chip microcomputer sends the working state of each path of balancing unit to the battery management system host through the CAN bus in real time, when the voltage difference between the single voltage value detected by the single chip microcomputer and the set voltage is reduced to the set voltage value, the battery management system host sends a balancing stopping instruction, after the single chip microcomputer receives the information, the Ax outputs a level signal, the switch tubes SxA and SxB are closed, meanwhile, a high level signal is given to an EN pin of the DC/DC module, and the output of the DC/DC module is closed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010442851.7A CN111572405A (en) | 2020-05-22 | 2020-05-22 | Active equalization system and method for lithium battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010442851.7A CN111572405A (en) | 2020-05-22 | 2020-05-22 | Active equalization system and method for lithium battery |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111572405A true CN111572405A (en) | 2020-08-25 |
Family
ID=72119285
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010442851.7A Pending CN111572405A (en) | 2020-05-22 | 2020-05-22 | Active equalization system and method for lithium battery |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111572405A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112165132A (en) * | 2020-09-25 | 2021-01-01 | 包头昊明稀土新电源科技有限公司 | Independent power supply and operation method thereof |
| CN112165130A (en) * | 2020-08-27 | 2021-01-01 | 北京精密机电控制设备研究所 | Servo power supply with independently controllable charging and discharging and implementation method thereof |
| CN112677822A (en) * | 2020-12-15 | 2021-04-20 | 台州市路桥鼎新阳光机电科技有限公司 | Battery management system |
| CN114940102A (en) * | 2022-05-27 | 2022-08-26 | 合肥哈工焕一新能源技术有限公司 | Charge-discharge balancing system for power battery of electric automobile |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202333857U (en) * | 2011-11-10 | 2012-07-11 | 张涛 | Active equalizer of lithium battery pack |
| CN103124094A (en) * | 2013-01-25 | 2013-05-29 | 浙江交通职业技术学院 | Active equalizing device of electric automobile power battery pack |
| CN109638924A (en) * | 2019-01-21 | 2019-04-16 | 安徽天健环保车辆部件有限公司 | A kind of electric automobile lithium battery equalized maintenance system and its working method |
| CN109720234A (en) * | 2018-12-04 | 2019-05-07 | 深圳众力新能源科技有限公司 | A kind of two-way active equalization device and its system of vehicle mounted dynamic battery group |
-
2020
- 2020-05-22 CN CN202010442851.7A patent/CN111572405A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202333857U (en) * | 2011-11-10 | 2012-07-11 | 张涛 | Active equalizer of lithium battery pack |
| CN103124094A (en) * | 2013-01-25 | 2013-05-29 | 浙江交通职业技术学院 | Active equalizing device of electric automobile power battery pack |
| CN109720234A (en) * | 2018-12-04 | 2019-05-07 | 深圳众力新能源科技有限公司 | A kind of two-way active equalization device and its system of vehicle mounted dynamic battery group |
| CN109638924A (en) * | 2019-01-21 | 2019-04-16 | 安徽天健环保车辆部件有限公司 | A kind of electric automobile lithium battery equalized maintenance system and its working method |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112165130A (en) * | 2020-08-27 | 2021-01-01 | 北京精密机电控制设备研究所 | Servo power supply with independently controllable charging and discharging and implementation method thereof |
| CN112165132A (en) * | 2020-09-25 | 2021-01-01 | 包头昊明稀土新电源科技有限公司 | Independent power supply and operation method thereof |
| CN112677822A (en) * | 2020-12-15 | 2021-04-20 | 台州市路桥鼎新阳光机电科技有限公司 | Battery management system |
| CN114940102A (en) * | 2022-05-27 | 2022-08-26 | 合肥哈工焕一新能源技术有限公司 | Charge-discharge balancing system for power battery of electric automobile |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111572405A (en) | Active equalization system and method for lithium battery | |
| CN102185159B (en) | Basic unit lithium battery pack module, multistage lithium battery pack and charge and discharge equilibrium method | |
| US7936150B2 (en) | Battery cell protection and conditioning circuit and system | |
| CN101752624B (en) | Equalizing charge method and equalizing charge device for battery | |
| CN102130483B (en) | Equalizing charging and discharging method for power type lithium-ion battery | |
| CN102664433A (en) | Cell equalization system based on bidirectional DC/DC | |
| CN108336780B (en) | Control method and system for gradient utilization of battery pack | |
| CN104953684A (en) | Dynamic equalization circuit of battery management system and dynamic equalization method of dynamic equalization circuit | |
| CN107565629A (en) | The fault-tolerant balanced management system of aeronautical cell power supply | |
| CN108001265A (en) | A kind of battery management system equipped with serial communication detection | |
| CN209948703U (en) | Lithium battery voltage-sharing control system | |
| CN203205956U (en) | Storage battery formation circuit and device | |
| CN110911765B (en) | Battery equalization strategy verification platform | |
| CN210608604U (en) | High-voltage battery system | |
| CN217741342U (en) | Communication isolation control circuit, battery management system and power supply | |
| CN117081191A (en) | Reconfigurable battery system | |
| CN203896026U (en) | Active equalization system of electromobile storage battery pack | |
| CN215378533U (en) | Control system of battery pack | |
| CN103165943A (en) | Storage battery formation method, circuit and device | |
| CN207117217U (en) | A kind of solar street light charge and discharge balancing system | |
| CN211377622U (en) | Balancing device of BMS | |
| CN112737040A (en) | UUV battery pack intelligent cascading extension architecture and cascading extension method | |
| CN215474598U (en) | Low-cost small-size miniature electric vehicle battery management system | |
| CN218957819U (en) | Centralized serial electrochemical energy storage controller | |
| CN220209991U (en) | Active equalization device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200825 |