CN105024411B - A kind of intelligent power lithium ion battery management system and its charge control method - Google Patents

Abstract

The invention relates to an intelligent power lithium-ion battery management system, which includes a microcontroller module and an acquisition module connected thereto, a storage module, a safety protection module, a communication module, a charge and discharge control module, and a balance management module; the charging method includes: The acquisition module collects information such as the voltage of the single battery, the total voltage, temperature, and current of the battery pack, and judges whether the battery is allowed to be charged; if allowed, the battery management system automatically adjusts the charging mode of the battery pack; automatically adjusts the balanced power supply through CAN communication The output current of the module is used to charge the single cells with lower voltage in an equalized manner until the voltage difference of all the single cells is less than the threshold. The invention can automatically select the charging mode according to the data information of the battery pack, automatically match the charging current, has a charging protection function, can improve the charging efficiency of the battery pack, and prolong the cycle life of the battery pack.

Description

An intelligent power lithium-ion battery management system and charging control method thereof

technical field

The invention belongs to the field of power battery management systems, in particular to a battery management system for power lithium-ion batteries and a charging control method thereof.

Background technique

With the development of electric vehicles and hybrid power tools, various power batteries are widely used. Lithium batteries have become the most promising power batteries due to their small size, low self-discharge rate, high energy density, and long cycle life. However, the safety and stability of lithium batteries are not high, and overcharging and overdischarging will cause damage to lithium-ion batteries. Therefore, in order to ensure the safe operation of lithium-ion batteries, a high-performance battery management system must be equipped.

The existing lithium battery management system has a single charging strategy and mostly uses constant current charging, which cannot be charged reasonably according to the characteristics of the battery. The charging efficiency is often low and it is easy to cause damage to the lithium-ion battery and shorten its service life. At the same time, most lithium battery management systems adopt passive equalization, which has low equalization efficiency and easily leads to heat management problems.

Contents of the invention

The object of the present invention is to provide an intelligent power lithium-ion battery management system with stable performance, low cost, low power consumption, high charging efficiency and good equalization effect, so as to overcome the defects of the above-mentioned battery management system.

The technical solution adopted by the present invention to achieve the above object is: an intelligent power lithium-ion battery management system, including: a microcontroller module and an acquisition module connected to it, a storage module, a safety protection module, a communication module, and a charge and discharge control module , Balance management module; acquisition module, charge and discharge control module, and balance management module are used to connect the battery unit;

Microcontroller module: control the charging and discharging control module, safety protection module and balance management module according to the battery data information of the acquisition module, and send the battery data information and status information to the external device controller through the communication module, and store them in the storage module;

Charge and discharge control module: used to connect the battery unit, manage the charging and discharging process of the battery pack, and realize the automatic charging of the lithium battery pack;

Balance management module: used to reduce the difference between the capacity of single batteries during the charging process of the battery pack, and realize automatic error detection and automatic configuration of the balance current.

The output end of the charging and discharging control module and the output end of the safety protection module are respectively connected to the two input ends of the AND gate, and the output end of the AND gate is connected to the G poles of the field effect transistor N1 and the field effect transistor N2, and the field effect transistor N1 , D pole of N2 and one end of relay N3 are connected to the negative pole of the battery unit through the current sensor and fuse in turn, the S poles of field effect transistors N1 and N2 are connected in parallel to the negative pole of the charger, and the positive pole of the charger is connected to the battery unit The other end of the relay N3 is connected to the positive pole of the battery unit through the load, the control end is connected to the microcontroller module, the charger is connected to the communication module through the CAN bus, and the balance power module, balance management module and The positive and negative poles of each single cell of the battery unit are connected.

The balance management module includes a plurality of diodes and a switch array, and the switch array is used to control the equalization charging on and off of each single battery, including a plurality of switches; after the positive and negative poles of each single battery are connected in series with diodes and switches, Connect with the positive and negative output terminals of the balanced power module.

A charging control method for an intelligent power lithium-ion battery management system, comprising the following steps:

According to the single battery voltage collected by the acquisition module, the total voltage, temperature and total current of the battery pack, judge whether to perform charging protection; if charging protection is required, disconnect the FET N1 and FET N2, and communicate through CAN at the same time Prohibit the output of the charger and the balanced power module;

If charging protection is not required, it will enter the pre-charging stage. In the pre-charging stage, if the single battery meets the condition of equalization opening, it will perform equalization charging. At the same time, the microcontroller module controls the equalization power supply module to turn on the relay N5 through CAN communication. Turn off relay N4 and relay N6, and the balanced power module outputs at 5V/3A; if not satisfied, go to the next step;

Enter the fast charging stage. In the fast charging stage, if the single battery meets the condition of equalization opening, the equalization charging will be carried out. At the same time, the microcontroller module controls the equalization power module to turn on N6 and turn off N4 and N5 through CAN communication. 5V/5A output; if not satisfied, go to the next step;

Enter the saturated charging stage. In the saturated charging stage, if the single battery meets the condition of equalization opening, the equalization charge will be carried out. At the same time, the microcontroller module controls the equalization power module to turn on N4 and turn off N5 and N6 through CAN communication. The equalization power supply is 5V /1A output; if not satisfied, go to the next step;

Enter the supplementary charging stage. In the supplementary charging stage, each single battery is charged in turn through the equalization management module and the switch and the CAN communication control equalization module until all the single batteries reach the charging cut-off voltage Vsstop, the charging is ended, and the equalization is turned off. Manage all the switches of the module, and control the balanced power supply module to close the relays N5, N4, and N6 through CAN communication.

The determination of whether to perform charging protection is specifically: when the following situations occur, it is considered that charging protection is required, otherwise charging protection is not required:

The acquisition module acquires that the temperature of the battery pack is higher or lower than the limit value within 5 consecutive seconds;

The total voltage of the battery pack is higher than the limit for 2s in a row, or the voltage of any single battery is higher than the limit for 2s in a row;

After the battery pack communicates with the charger successfully, if the battery pack sends a charging request, the acquisition module does not detect the charging current for 10 consecutive seconds, or the battery pack does not send a charging request, and the acquisition module detects that the charging current is greater than 2A for 10 consecutive seconds.

The pre-charging includes the following steps:

If the total voltage of the battery pack is lower than the total voltage limit Vtpre of the pre-charged battery pack or the voltage of any single cell is lower than the voltage limit Vspre of the pre-charged single cell, the microcontroller module controls the field effect transistor N1 and the field effect transistor N2 Turn on, and adjust the charger to output at a constant current of 0.05C through CAN communication.

The fast charging includes the following steps:

When the total voltage of the battery pack is greater than the threshold Vspeed, the microcontroller module controls the field effect transistor N1 and the field effect transistor N2 to conduct, and adjusts the charger to output a constant current of 0.5C through CAN communication.

Described saturated charge comprises the following steps:

When the total voltage of the battery pack is greater than the threshold Vsatura, the microcontroller module adjusts the charger to output a constant current of 0.2C through CAN communication until the total voltage of the battery pack reaches the charging cut-off voltage Vtstop or the voltage of the single battery reaches the charging cut-off voltage Vsstop, and then disconnects The field effect transistor N1 and the field effect transistor N2 control the charger through CAN communication to prohibit the output of the charger.

The supplementary charging includes the following steps:

Carry out supplementary charging for each single battery in turn, that is, control the balanced power supply module through CAN communication to turn on relay N5, close relays N4 and N6, control the multi-way switch of the balanced management module (8), and turn on the power supply of each single battery in turn. Equalize the path, so far the voltage of the single battery reaches the threshold voltage Vsstop.

The condition for opening the equalization is: after it is judged that the battery unit is not faulty, the voltage difference between the single battery with the highest voltage and the single battery with the lowest voltage is greater than the equalization open limit value Udva. Specifically: according to the voltage of the single battery collected by the acquisition module, it is judged whether the battery unit is faulty; if there is no fault, when the voltage difference between the single battery with the highest voltage and the single battery with the lowest voltage is greater than the balance opening limit value Udva, If there is a fault, it will not enter the equalization charging, and at the same time, the microcontroller module controls the equalization power supply module to turn off the relays N4, N5 and N6 through CAN communication.

The balanced charging specifically includes: charging the battery unit with the lowest voltage, and adjusting the output current of the balanced power module through CAN communication according to the charging stage of the battery until the voltage difference of all single batteries is less than the threshold value Udvb.

The present invention has the following beneficial effects and advantages:

1. The present invention is a centralized battery management system, which has the characteristics of small size, stable performance, high acquisition accuracy, low cost, and strong reliability.

2. The power lithium-ion battery management system of the present invention uses the CAN communication network and performs charging control in combination with battery characteristics. It can automatically select the charging mode according to the battery pack data information, automatically match the charging current, and has a charging protection function, which can improve the performance of the battery pack. High charging efficiency, prolonging the cycle life of the battery pack.

3. The present invention provides a balanced charging control method, which communicates with the balanced power supply module through the CAN communication network, automatically starts and closes the balanced charging according to the data information of the battery pack, and can automatically configure the balanced current in different charging stages of the battery pack, and in the main After the charging is completed, supplementary charging is performed on each single battery in turn, which improves the capacity consistency among the single batteries.

4. The present invention provides a balanced power supply module, which can adjust the output current through CAN communication, and provide adjustable power supply for the balanced charging of the battery pack.

Description of drawings

Fig. 1 is a frame diagram of the intelligent power lithium-ion battery management system of the present invention.

Figure 2 is a schematic diagram of the principle of the charging and discharging control module.

Figure 3 is a schematic diagram of the principle of the balanced power supply module.

Fig. 4 is a schematic diagram of the principle of the balance management module.

Figure 5 is a flowchart of the charging control algorithm.

detailed description

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

The invention provides an intelligent power lithium-ion battery management system, which includes a microcontroller module 1, a power module 7, an acquisition module 2, a charge and discharge control module 6, a safety protection module 4, a communication module 5, a storage module 3 and an equalizer Management module8. The battery management system can monitor and manage the lithium battery voltage, temperature, current and battery state of charge (SOC for short) in real time, and use the CAN communication network to automatically charge the battery pack, that is, automatically adjust the charging mode according to the battery pack data information, Perform balanced management on single batteries with poor capacity consistency, automatically configure balanced charging current, and improve the capacity consistency of lithium batteries. The battery management system can improve the charging efficiency of the battery, prolong the service life, and ensure the safe and stable operation of the battery pack.

As shown in Figure 1, the power module 7 of the present invention is respectively connected with the acquisition module 2, the microcontroller module 1, the communication module 5, the storage module 3, and the safety protection module 4, and provides 5 module working voltages to ensure that the battery management system is normal Work.

The acquisition module 2 is used to detect the voltage of the single battery, the total voltage of the battery pack, the total current and the temperature; it is composed of the temperature, the total voltage, the voltage of the single battery, the total current and the balance current acquisition circuit. The acquisition circuit is composed of a differential operational amplifier and a voltage divider resistor. The temperature sensor is a thermistor. The current sensor required for total current acquisition is a precision resistor. The current sensor required for balanced current acquisition is a Hall current sensor.

Described microcontroller module 1 is the core module of whole system, and it receives the data information of collection, and processes; Carry out corresponding logic operation according to the data information obtained, estimate SOC, control security protection module 4, balance management module 8, The charging and discharging control module 6 writes the collected data information, system status information and fault information into the storage module 3, and interacts with external devices (such as the vehicle controller) through the communication module 5 .

The charging and discharging control module 6 is used to manage the charging and discharging process of the battery pack, so as to realize the intelligent automatic charging of the lithium battery pack. It is composed of charging control circuit and discharge control circuit. The charging and discharging process is controlled by the microprocessor module. The charging control of the battery pack adopts pre-charging, fast charging, saturated charging and supplementary charging in stages, and is combined with balanced charging management. , The battery management system can automatically configure the charging mode according to the battery pack data information, and communicate with the charger and the balancing power module through the CAN communication network to automatically configure the charging current and balancing current.

The safety protection module 4 is used for fault detection of the battery management system and the battery pack, so as to prevent the occurrence of safety accidents. Receive the signal output by the microprocessor when judging that a potential safety hazard occurs, enable the protection control signal according to the level, and generate corresponding protection actions.

The communication module 5 receives the information sent by the microcontroller module and sends it to the external communication device, and at the same time receives the instruction information sent by the external communication device and forwards it to the microcontroller module for processing.

The storage module 3 is a non-volatile memory module, connected to the microprocessor module 1, capable of non-volatile storage, reading and writing, fast storage speed, and can store data information and status information of the lithium battery management system, And the stored information will not be lost when the management system is powered off, and the data information of the lithium-ion battery management system can be permanently stored.

The balance management module 8 is used to reduce the difference between the capacities of the single batteries during the charging process of the battery pack, and has the functions of automatic error detection and automatic configuration of the balance current. Composed of multiple identical switch arrays, it has strong portability. One end of the balance management module switch array is connected to the balance power supply module, and the other end is connected to the single battery, and each switch array is controlled by a microcontroller module. When a certain battery unit reaches the balanced open state, the corresponding switch array is turned on to charge the single battery.

The balanced power supply module is composed of CAN communication module, MCU module, 3 power conversion modules, multiple switches and diodes, can communicate with the battery management system, and perform corresponding actions according to the instructions of the battery management system. The balance management module provides the required input power.

As shown in Figure 2, the charging and discharging control module 6 of the present invention is connected with the charger and the equalizing power supply module 8 through CAN communication; the starting charging signal of the charging and discharging control module 6 and the charging protection signal of the charging protection module in the safety protection module 4 The gate is connected to the G poles of field effect transistors N1 and N2, and the control terminal of relay N3 is connected to the microcontroller module 1 of the battery management system. The D poles of N1 and N2 and one end of N3 are connected in parallel, and then pass through the current sensor and fuse in turn. Connect to the negative pole of the battery unit; the S poles of the field effect transistors N1 and N2 are connected in parallel to the negative pole of the charger, the other end of the field effect transistor N3 is connected to the load, and the positive end of the battery pack is used as a charging port to connect the charger and the load , if the charging of the battery pack is started, the microcontroller module 1 controls the output of the charging control module 6, so that N1 and N2 are connected, and the relay N3 is turned off; if the battery pack starts discharging, the microcontroller module 1 controls the charging and discharging control module 6 output, so that N1 and N2 are disconnected, and relay N3 is connected.

The safety protection module 4 proposed by the present invention mainly realizes a series of protection functions such as battery system overcharge, overdischarge, overtemperature, low temperature, overcurrent, balance failure, fuse failure, etc., to ensure safe and stable operation of the battery pack. According to the faults detected by the battery management system, the importance and safety of the system operation are graded. The protection function of this safety protection module is divided into three levels of protection. The first level of protection is minor and alarm prompts; the second level of protection is serious Level, the alarm prompts and disconnects the relevant working circuits, and stops the corresponding associated actions; the third level of protection is fuse protection, which cuts off the total output power. All control signals are issued by the microcontroller after logical judgment based on the processed data information.

The communication module 5 proposed by the present invention uses the CAN communication network to communicate with the charger, the equalizing power supply module and external devices to realize charging control, equalizing control and external data interaction.

As shown in Figure 4, the balance management module (8) proposed by the present invention is composed of a multi-way switch selection circuit, the positive and negative poles of the first single battery are connected in series with the diodes D7 and D8 respectively, and are connected with the switches S1 and S2, and the S1 The other end of S2 and S2 are respectively connected to the positive and negative poles of the balanced power supply. Similarly, the balanced circuits of other single batteries are also connected in the same way as above. If the balanced charging of a single battery is started, the two switches of this balanced branch are closed, and the switches of all other branches are turned off at the same time.

The balanced power supply module proposed by the present invention is shown in Figure 3, including MCU module U1, CAN communication module U2, P1 (5V/1A), P2 (5V/3A), P3 (5V/5A) power conversion modules, switches ( Relay) N4, N5, N6, and diodes D1, D2, D3, D4, D5, D6; the CAN communication module (U2) is connected to the communication module 5 of the battery management system, which is used for the balanced power module to receive control commands and return execution results ;The MCU module (U1) is connected to the CAN communication module (U2) through a serial communication line; the control terminal of the switch N4 is electrically connected to the MCU module (U1), and the other two ends are respectively connected to the positive pole of D1 and the positive pole of P1, and the control terminal of the switch N5 It is electrically connected to the MCU module (U1), and the other two ends are respectively connected to the positive pole of D3 and the positive pole of P2. The control terminal of switch N6 is electrically connected to the MCU module (U1), and the other two ends are respectively connected to the positive pole of D5 and the positive pole of P3. The negative terminals of diodes D1, D3 and D5 are connected in parallel as the positive terminals of the balanced power supply module. The negative terminal of D2 is connected to the negative terminal of P1, the negative terminal of D4 is connected to the negative terminal of P2, the negative terminal of D6 is connected to the negative terminal of P3, and the positive terminals of D2, D4 and D6 are connected in parallel as the negative terminals of the balanced power module. The MCU module (U1) receives instructions from the battery management system through the CAN communication module (U2), and then selects one of the power modules of P1, P2, and P3 to turn on by controlling the switches N1, N2, and N3 according to the instructions. , or all off, output the corresponding current and voltage according to the requirements of the communication protocol, and after the output is turned on, return the balanced power supply to the battery management system through the CAN communication to output the normal output command.

In the equalization control algorithm proposed by the present invention, the battery management system detects whether the equalization power supply module is connected through a mechanical contact. The battery management system does not detect the equalization current within 5s, or the equalization is not turned on, and the battery management system detects the equalization current within 5s, then equalizes the charging protection, turns off all the multi-channel selection switches of the equalization management module 8, and prohibits equalization through CAN communication. Output of power module 8. If there is no fault in the balanced self-test and balanced charging, then enter the balanced charging control algorithm, and find the single battery with the highest voltage and the single battery with the lowest voltage according to the voltage of the single battery collected by the acquisition module 2. If two single batteries If the voltage difference is greater than the equalization opening limit value Udva, then the equalization charging of the single battery with a lower voltage is started, that is, the equalization charging is carried out by turning on the switch on the equalization branch circuit of this single battery, and the adjustment is made through CAN communication. Balance the output current of the power module until the voltage difference of all single cells is less than the balance stop threshold Udvb, and turn off the switches of all balance branches.

As shown in FIG. 5 , a charging control algorithm for an intelligent power lithium battery pack proposed by the present invention includes pre-charging, fast charging, saturated charging and supplementary charging. In the stages of pre-charging, fast charging, and saturated charging, the power lithium-ion battery management system performs equalization management at the same time according to the voltage information of the single battery. When the voltage of the battery pack is low, the pre-charging mode is used, and it is switched to the fast charging mode after 10 minutes. When the battery pack is charged to the end, that is, when the battery pack voltage reaches a certain value, it is switched to saturated charging, and the balanced charging is in the above three charging modes. Both can be started, and each single battery is supplemented with charge after the saturated charge is completed. In order to ensure the safety of charging the battery pack, real-time self-inspection is performed during the charging process. Once there is a problem that causes charging safety, it will immediately enter the charging protection.

(1) Charging protection: According to the single battery voltage, battery pack total voltage, temperature and current data collected by the acquisition module 2, the charging protection function is judged. Charging protection functions include battery pack overheating protection, overcooling protection, overvoltage protection, and charging failure protection. The battery pack overheating protection is when the acquisition module 2 collects that the battery pack temperature is higher than the overheating limit for 5 consecutive seconds, the battery pack overheating protection; When the overcooling limit is reached, the battery pack is under overcooling protection; the battery pack overvoltage protection is when the acquisition module 2 collects that the total voltage of the battery pack is higher than the limit for 2 seconds, or the voltage of any single battery is higher than the limit for 2 seconds. When the limit value is reached, the battery pack is overvoltage protected; the battery pack charging failure is when the battery pack and the charger communicate successfully, if the battery pack sends a charging request, the acquisition module 2 does not detect the charging current for 10 seconds, or the battery pack does not send a charging request If the acquisition module 2 detects that the charging current is greater than 2A for 10 consecutive seconds, it is considered that there is a charging failure. Once the battery management system is charging and protected, disconnect N1 and N2, cut off the charging circuit, and prohibit the output of the charger and the equalizing power module through CAN communication.

(2) Pre-charging: If the battery pack has no safety faults that cause charging, that is, when charging protection is not performed, according to the data of the total voltage of the battery pack and the voltage of the single battery collected by the acquisition module 2, if the total voltage of the battery pack is lower than the preset When the total voltage limit Vtpre of the rechargeable battery pack or the voltage of any single battery is lower than the voltage limit Vspre of the pre-charged single battery, the battery management system closes N1 and N2 to connect the charging circuit, and adjusts the charger through CAN communication to make it 0.05C constant current output. At this time, if the single battery meets the condition of equalization, it will enter the equalization control algorithm. At the same time, through CAN communication, the equalization power module is controlled to turn on N5, turn off N4 and N6, and the equalization power is output at 5V/3A.

(3) Fast charging: If the battery pack has no safety faults that cause charging, that is, when charging protection is not performed, according to the data of the total voltage of the battery pack and the voltage of the single battery collected by the acquisition module 2, when the total voltage of the battery pack is greater than Vspeed , the battery management system adjusts the charger to output at a constant current of 0.5C through CAN communication. At this time, if the single battery satisfies the conditions for opening the balance, it will enter the balance control algorithm, and at the same time control the balance power module to turn on N6 through CAN communication, turn off N4 and N5, and the balance power will be output at 5V/5A.

(4) Saturation charging: If the battery pack has no safety faults that cause charging, that is, when charging protection is not performed, according to the data of the total voltage of the battery pack and the voltage of the single battery collected by the acquisition module 2, when the total voltage of the battery pack is greater than Vsatura , the battery management system adjusts the charger through CAN communication to output a constant current of 0.2C until the total voltage of the battery pack reaches the charging cut-off voltage Vtstop or the voltage of the single battery reaches the charging cut-off voltage Vsstop, disconnect N1 and N2, and cut off the charging circuit. The charger is controlled by CAN communication to prohibit the output of the charger. At this time, if the single battery satisfies the conditions for opening the balance, it will enter the balance control algorithm, and at the same time control the balance power module through CAN communication to turn on N4, turn off N5 and N6, and the balance power will be output at 5V/1A.

(5) Supplementary charging: After the saturated charging is completed, supplementary charging is performed on each single battery in turn, that is, through CAN communication, the balanced power supply module is controlled to turn on the relay N5, close the relays N4 and N6, and control the balance management module (8) Multi-way switch, turn on the equalization path of each single battery in turn, so far the voltage of the single battery reaches the threshold voltage Vsstop, after all the voltages of the single batteries are supplemented and charged in turn, turn off all the switches of the equalization management module 8, and communicate through CAN Control the balanced power supply module to close the relays N5, N4, and N6.

Claims (10)

1. a kind of intelligent power lithium ion battery management system, it is characterised in that include：Micro controller module (1) and connect with which The acquisition module (2) that connects, memory module (3), security protection module (4), communication module (5), charge and discharge control module (6), Weighing apparatus management module (8)；Acquisition module (2), charge and discharge control module (6), balanced management module (8) are used for connecting battery unit；

Micro controller module (1)：Charge and discharge control module (6), safety are controlled according to the battery data information of acquisition module (2) to protect Shield module (4) and balanced management module (8), and battery data information and status information are sent to by communication module (6) Device controller, and store memory module (3)；

Charge and discharge control module (6)：For connecting battery unit, and the charge and discharge process to set of cells is managed, and it is right to realize The automatic charging of lithium battery group；

Balanced management module (8)：For reducing the difference between cell capacity in set of cells charging process, and realize certainly Dynamic error detection with automatically configure euqalizing current；

The outfan of charge and discharge control module (6) and the outfan of security protection module (4) respectively with defeated with the two of door Enter end connection, be connected with the G poles of field effect transistor N1, field effect transistor N2 with gate output terminal, the D poles of field effect transistor N1, N2 and relay Connect through the negative pole of current sensor, fuse and battery unit after one end connection of device N3 successively, the S of field effect transistor N1, N2 Extremely it is connected with charger negative pole after parallel connection, the positive pole of charger is connected with the positive pole of battery unit；The other end of relay N3 leads to Overload is connected with the positive pole of battery unit, and control end is connected with micro controller module (1), and charger passes through CAN and leads to News module (5) connection, also by each list for the balanced power module, balanced management module (8) and battery unit being sequentially connected Body battery plus-negative plate connects.

2. a kind of intelligent power lithium ion battery management system according to claim 1, it is characterised in that the equalizer line Reason module (8) includes that multiple diodes and switch arrays, switch arrays are used for controlling the equalizaing charge of each cell and open Open and closing, including multiple switch；After each cell both positive and negative polarity difference series diode, switch, with balanced power module Positive-negative output end connection.

3. a kind of charge control method of intelligent power lithium ion battery management system, it is characterised in that comprise the following steps：

According to the monomer battery voltage that acquisition module (2) is collected, assembled battery total voltage, temperature and total current, judge whether into Row charge protection；If desired protection is charged, then disconnects field effect transistor N1 and field effect transistor N2, while prohibiting by CAN communication Only charger and balanced power module output；

If protection need not be charged, pre-charging stage is entered, if cell meets equilibrium and opens in pre-charging stage The condition for opening, then carry out equalizaing charge, at the same micro controller module (1) by CAN communication control balanced power module connect after Electrical equipment N5, closes relay N4, relay N6, and balanced power module is exported with 5V/3A；If being unsatisfactory for, next step is executed；

The quick charge stage is entered, if cell meets the balanced condition that opens in the quick charge stage, equilibrium is carried out Charge, while micro controller module (1) controls balanced power module by CAN communication connects N6, close N4 and N5, balanced power supply Module is exported with 5V/5A；If being unsatisfactory for, next step is executed；

The saturation charging stage is entered, if cell meets the balanced condition that opens in the saturation charging stage, equilibrium is carried out Charge, while micro controller module (1) controls balanced power module by CAN communication connects N4, close N5 and N6, balanced power supply Exported with 5V/1A；If being unsatisfactory for, next step is executed；

The boost charge stage is entered, in the boost charge stage, is controlled by balanced management module (8) and switch and CAN communication Weighing apparatus module is charged to every cell successively, until all cells reach charge cutoff voltage Vsstop, is tied Beam charges, and closes all switches of balanced management module (8), and by CAN communication control balanced power module closing after Electrical equipment N5, N4, N6.

4. the charge control method of a kind of intelligent power lithium ion battery management system according to claim 3, its feature Charge protection is judged whether to described in being to be specially：Then think when there are following situations that needs are charged protection, otherwise Protection need not be charged：

Acquisition module (2) is collected in the continuous 5s of battery pack temperature higher or lower than limit value；

The continuous 2s of assembled battery total voltage is higher than limit value, or the continuous 2s of any one monomer battery voltage is above limit value；

Set of cells is communicated after success with charger, if set of cells sends charge request, continuous 10s acquisition modules (2) are not detected by Charging current, or set of cells do not send charge request, continuous 10s acquisition modules (2) detect charging current more than 2A.

5. the charge control method of a kind of intelligent power lithium ion battery management system according to claim 3, its feature It is that the precharge is comprised the following steps：If assembled battery total voltage less than precharge cell group total voltage limit value Vtpre or Any one monomer battery voltage controls field effect less than precharge monomer battery voltage limit value Vspre, micro controller module (1) Pipe N1 and the conducting of field effect transistor N2, adjust charger with 0.05C constant current outputs by CAN communication.

6. the charge control method of a kind of intelligent power lithium ion battery management system according to claim 3, its feature It is that the quick charge is comprised the following steps：When assembled battery total voltage is more than threshold value Vspeed, micro controller module (1) is controlled Field effect transistor N1 processed and the conducting of field effect transistor N2, adjust charger with 0.5C constant current outputs by CAN communication.

7. the charge control method of a kind of intelligent power lithium ion battery management system according to claim 3, its feature It is that the saturation charges to comprise the following steps：When assembled battery total voltage is more than threshold value Vsatura, micro controller module (1) By CAN communication adjust charger with 0.2C constant current outputs, until assembled battery total voltage reach charge cutoff voltage Vtstop or Monomer battery voltage reaches charge cutoff voltage Vsstop, disconnects field effect transistor N1 and field effect transistor N2, by CAN communication control Charger forbids that charger is exported.

8. the charge control method of a kind of intelligent power lithium ion battery management system according to claim 3, its feature It is that the boost charge is comprised the following steps：

Boost charge is carried out to every cell successively, i.e., balanced power module is controlled by CAN communication and is connected relay N5, Relay N4 and N6 is closed, the variable connector of balanced management module (8) is controlled, the equilibrium for opening each cell successively is led to Road, so far monomer battery voltage reach threshold voltage Vsstop.

9. the charge control method of a kind of intelligent power lithium ion battery management system according to claim 3, its feature It is that the condition that the equilibrium is opened is：After judging battery unit fault-free, voltage highest cell and voltage are minimum The voltage difference of cell opens limit value Udva more than balanced.

10. the charge control method of a kind of intelligent power lithium ion battery management system according to claim 3, its feature It is that the equalizaing charge is specially：The battery unit minimum to voltage is charged, and the charging stage according to residing for battery, The output current that balanced power module is adjusted by CAN communication, until the pressure reduction of all cells is respectively less than threshold value Udvb be Only.