TWI474578B - Battery pack with balancing management - Google Patents

Description

Battery management system and method for balancing battery modules in battery packs

The present invention relates to a battery management system, and more particularly to a system and method for balancing battery modules in a battery pack.

In the past few decades, various application demands (for example, power supplies) for electronic devices have been increasing, and thus, battery packs (for example, rechargeable battery packs) have been continuously developed.

The battery pack includes a plurality of battery cells coupled in series. When a battery unit is damaged, the life of the battery pack is shortened. When an imbalance occurs between any two battery cells, the life of the battery pack is also shortened. 1 is a block diagram of a conventional lead acid battery pack 100. Due to its simple structure, lead-acid battery pack 100 is typically used in low cost applications.

The lead-acid battery pack 100 includes a plurality of battery modules 101-104 coupled in series. Each battery module includes six battery cells 111-116 and two electrodes 120 and 129. Only the voltage of each battery module can be monitored via the two electrodes 120 and 129. Once any one of the battery cells 111-116 is damaged, the entire lead-acid battery pack 100 will be damaged; an imbalance between any two of the battery cells 111-116 will shorten the lead-acid battery pack 100. life.

An object of the present invention is to provide a battery management system for a battery pack, comprising: a plurality of battery modules, a plurality of first balancing units, respectively The plurality of battery modules are coupled to each other; the plurality of second balancing units are respectively coupled to the plurality of battery modules; and the plurality of controllers are respectively coupled to the plurality of battery modules, and the plurality of controllers When the first controller determines that the output voltage of the first battery module is greater than the output voltage of the first battery module and the second battery module, the first controller controls the first battery module a first balancing unit to adjust an output voltage of the first battery module. When the first controller determines the output voltage and is greater than an output voltage of the first battery module, the first controller controls the first A second balancing unit in the battery module adjusts the output voltage sum.

The present invention also provides a method for balancing a plurality of battery modules in a battery pack, comprising: comparing an output voltage of a first battery module with an output voltage of the first battery module and a second battery module; Adjusting the output voltage of the first battery module when the output voltage of the first battery module is greater than the output voltage, and adjusting the first battery mode when the output voltage is greater than the output voltage of the first battery module The sum of the output voltages of the group and the second battery module.

The present invention also provides a battery management system for a battery pack, comprising: means for comparing an output voltage of a first battery module with an output voltage of the first battery module and a second battery module, when Adjusting an output voltage of the first battery module when the output voltage of the first battery module is greater than the output voltage, and adjusting the output voltage when the output voltage is greater than an output voltage of the first battery module Device.

A detailed description of the embodiments of the present invention will be given below. Although this hair The invention will be explained in conjunction with the embodiments, but it should be understood that this is not intended to limit the invention to these embodiments. Rather, the invention is to cover various modifications, equivalents, and equivalents of the invention as defined by the scope of the appended claims.

In addition, in the following detailed description of the embodiments of the invention However, it will be understood by those of ordinary skill in the art that the present invention may be practiced without these specific details. In other instances, well-known methods, procedures, components, and circuits have not been described in detail in order to facilitate the invention.

2A is a block diagram of a battery management system 200 for a battery pack (eg, a lead acid battery pack) in accordance with an embodiment of the present invention. The life of the battery pack is extended by the balancing technique and the efficiency of the battery management system 200 is improved.

In one embodiment, the battery pack includes a plurality of battery modules 211-216 coupled in series. Each of the battery modules 211-216 includes a plurality of battery cells, for example, 3, 4, 5 or 6 battery cells. Taking the voltage of each battery cell as 2 volts as an example, the voltage of each battery module is 6 volts, 8 volts, 10 volts or 12 volts according to the corresponding number. The battery pack is coupled to the balancing unit 220. In one embodiment, the balancing unit 220 includes a plurality of balancing circuits 221-226 coupled to the battery modules 211-216, respectively. More specifically, the balancing circuit 221 is coupled to the battery module 211, the balancing circuit 222 is coupled to the battery module 212, and the like. However, the number of battery cells, battery modules, and balancing circuits is not limited thereto, and the number thereof may vary depending on the needs of different applications. For the sake of brevity and clarity, the following is included A 12-volt battery module of six battery cells is described in detail as an example.

The controller 230 is coupled to the battery pack (eg, the battery modules 211-216) and monitors parameters (eg, voltage and/or temperature) of the battery modules 211-216. In one embodiment, controller 230 instantly monitors the voltage of battery modules 211-216 and calculates the voltage difference between battery modules 211-216. The controller 230 determines whether or not an imbalance has occurred based on the voltage difference. When an imbalance occurs between the battery modules 211-216, the controller 230 controls the corresponding balancing circuit to adjust the voltage of the unbalanced battery module. In one embodiment, controller 230 sets a threshold _VTHM for determining if an imbalance has occurred. If the voltage difference between the battery modules 211-216 is greater than the threshold value _VTHM , the controller 230 determines that an imbalance has occurred. Next, the controller 230 activates a corresponding balancing circuit to adjust the voltage of the unbalanced battery module.

In one embodiment, controller 230 detects that the voltages of battery modules 211 and 212 are V _M1 and V _M2 , respectively, for example, 12.4 volts and 12 volts, respectively. If the voltage difference ΔV _M12 between the battery modules 211 and 212 is greater than the threshold value V _THM (for example, 0.1 volt), the controller 230 determines that an imbalance has occurred between the battery modules 211 and 212. Under the control of the controller 230, the balancing circuits 221 and 222 adjust the voltages of the battery modules 211 and 212 to balance the battery modules 211 and 212 so that the voltage difference ΔV _M12 between the battery modules 211 and 212 is no longer greater than Limit value V _THM . In one embodiment, in the passive mode, the balancing circuit 221 discharges the battery module 211 during discharge or bypasses the battery module 211 during the charging process. Discharge or bypass after one or more cycles until ΔV _M12 falls to the threshold V _THM . In another embodiment, in the active mode, the energy of the battery module 211 is transferred to the battery module 212 via a transformer (not shown) until ΔV _M12 falls to the threshold V _THM .

In one embodiment, if an imbalance occurs between the plurality of battery modules, the controller 230 calculates a voltage difference between the battery modules and prioritizes the voltage differences. For example, the voltage difference having the maximum value is set to the highest priority order, and the voltage difference having the minimum value is set to the lowest priority order. If two or more voltage differences have the same value, these voltage differences are set to the same priority order. The controller 230 adjusts the unbalanced battery modules according to the priority order. In one embodiment, if two or more voltage differences have the same priority order, the controller 230 simultaneously controls the corresponding balancing circuit to adjust the unbalanced battery module. In another embodiment, if the battery management system 200 employs a chiller or fan to address thermal issues, the controller 230 does not need to determine and/or prioritize the voltage differences while adjusting all of the unbalanced battery modules.

In one embodiment, an electronic control unit (ECU) 240 is coupled to the controller 230 via the bus bar 250 and processes data from the controller 230, including but not limited to the battery module 211- 216 voltage and / or temperature. The electronic control unit 240 provides software support for balance management of the battery pack. Electronic control unit 240 may also display the data and/or communicate the data to other devices (not shown) for further processing. Electronic control unit 240 is an optional configuration. In one embodiment, the electronic control unit 240 may be omitted for cost savings.

Advantageously, the controller 230 instantly monitors the voltage difference between the battery modules 211-216 and controls the corresponding balancing circuit to adjust the voltage of the unbalanced battery module. Therefore, the above measures can be taken to prevent the battery module from being unbalanced and damaged. Extended battery because the battery module uses balancing technology The life of the group.

2B is a block diagram showing a balancing circuit 220B in a battery management system for a battery pack (e.g., a lead-acid battery pack) in a passive mode in accordance with an embodiment of the present invention. Figure 2B is described in conjunction with Figure 2A. In one embodiment, the balancing circuit (e.g., balancing circuits 221-226) of Figure 2A employs the configuration of balancing circuit 220B shown in Figure 2B.

In one embodiment, balancing circuit 220B includes a resistor 281 and a switch 282 coupled in series. The balancing circuit 220B is coupled to one of the battery modules of FIG. 2A. More specifically, one end of the resistor 281 is coupled to the anode of a battery module, and one end of the switch 282 is coupled to the cathode of the battery module. Controller 230 controls switch 282.

In one embodiment, the first balancing circuit is coupled to the first battery module, and the second balancing circuit is coupled to the second battery module, wherein the voltage of the first battery module is greater than the voltage of the second battery module. When the voltage difference between the first battery module and the second battery module is greater than the threshold value, an imbalance occurs. At this time, the controller 230 turns on the first switch in the first balancing circuit and turns off the second switch in the second balancing circuit. During the discharging process, the discharging current flows through the first resistor in the first balancing circuit, whereby the first balancing circuit discharges the first battery module until the first battery module and the second battery module reach balance. During the charging process, the bypass current flows through the first resistor, whereby the first balancing circuit bypasses the first battery module until a balance is reached between the first battery module and the second battery module.

2C is a block diagram showing a balancing unit 220C in a battery management system for a battery pack (eg, a lead-acid battery pack) in an active mode in accordance with an embodiment of the present invention. In one embodiment, the balancing unit 220C includes a transformer. Figure 2C is described in conjunction with Figure 2A. In one embodiment, balancing unit 220C acts as balancing unit 220 in place of balancing circuits 221-226 in the embodiment shown in FIG. 2A.

In one embodiment, balancing unit 220C includes a plurality of secondary coils 291-296 coupled in series with a plurality of switches 291A-296A. Each of the secondary coils is coupled to a battery module. For example, one of the secondary coils 291-296 is sequentially coupled to one of the battery modules 211-216. More specifically, the secondary coil 291 is coupled to the battery module 211 via the switch 291A, the secondary coil 292 is coupled to the battery module 212 via the switch 292A, and the like. The balancing unit 220C also includes a primary coil 290 coupled in series with the switch 292A. Primary coil 290 is coupled to the battery pack via switch 290A. Controller 230 controls switches 290A-296A.

In one embodiment, the first secondary coil is coupled to the first battery module via the first switch, and the second secondary coil is coupled to the second battery module via the second switch, and the voltage of the first battery module is greater than The voltage of the second battery module. An imbalance occurs when the voltage difference between the first battery module and the second battery module is greater than the threshold. At this time, the controller 230 turns on the first switch and turns off the other switches, whereby the energy of the first battery module is stored on the first secondary coil. In one embodiment, the controller 230 turns on the second switch and turns off the other switches, whereby the energy of the first secondary coil is transferred to the second secondary coil. In another embodiment, controller 230 turns on switch 290A and turns off the other switches, whereby the energy of the first secondary coil is transferred to primary coil 290. The battery modules 211-216 can share the energy of the primary coil 290. The above process is repeated until a balance is reached between the first battery module and the second battery module.

3 is a block diagram of a battery management system 300 for a battery pack (eg, a lead acid battery pack) in accordance with another embodiment of the present invention. The use of balancing techniques can extend the life of the battery pack and increase the efficiency of the battery management system 300.

In one embodiment, the battery pack includes a plurality of battery modules (not shown) coupled in series. FIG. 3 shows a battery module, for example, a battery module 310. Battery module 310 also includes a plurality of batteries, such as batteries 301-306. The batteries 301-306 are coupled to the balancing unit 320. In one implementation, balancing unit 320 includes a plurality of balancing circuits, such as balancing circuits 321A-326A. The balancing circuits 321A-326A may employ the structure of the balancing circuit 220B of FIG. 2B. More specifically, balancing circuits 321A-326A include resistors 311-316 and switches 321-326 coupled in series. However, the number of batteries, battery modules, and balancing circuits is not limited thereto, and the number thereof may vary depending on the needs of different applications. The following is a detailed description of a 2 volt battery.

Controller 330 is coupled to battery module 310 (e.g., battery cells 301-306) and monitors parameters (e.g., voltage and/or temperature) of battery cells 301-306. In one embodiment, controller 330 instantly detects the voltages of battery cells 301-306 and calculates the voltage difference between battery cells 301-306. When an imbalance occurs between the battery cells 301-306, the controller 330 controls the respective balancing circuits 321A-326A to adjust the voltage of the unbalanced battery cells. In one embodiment, controller 330 sets threshold V _THC to determine if an imbalance has occurred. If the voltage difference between the battery cells 301-306 is greater than the threshold value _VTHC , the controller 330 determines that an imbalance has occurred. Next, the controller 330 activates a corresponding balancing circuit to adjust the voltage of the unbalanced battery unit.

In one embodiment, controller 330 detects that the voltages of battery cells 301 and 302 are V _C1 and V _C2 , respectively, for example, 2.1 volts and 2.0 volts, respectively. If the voltage difference ΔV _C12 between the battery cells 301 and 302 is greater than the threshold value V _THC , for example, 0.02 volts, the controller 330 determines that an imbalance occurs between the battery cells 301 and 302. In this case, the controller 330 controls the balancing circuits 321A and 322A to adjust the voltages of the battery cells 301 and 302 until the voltage difference between the battery cells 301 and 302 is no longer greater than the threshold value V _THC . In one embodiment, in the active mode, balancing circuit 321A discharges battery unit 301 during discharge or bypasses battery unit 301 during charging until ΔV _C12 decreases to a threshold value V _THC . More specifically, in this case, the controller 330 sends a control signal to the switch 321, and then the switch 321 continues to conduct for one or more cycles. Thereby, a current flows through the resistor 311 and the switch 321, and V _{C1 is} lowered. Once VC1 drops to a voltage value that can balance between battery cells 301 and 302, controller 330 turns off switch 321, which in turn suspends or bypasses battery cell 301.

In one embodiment, if an imbalance occurs between the plurality of battery cells, the controller 330 can calculate the voltage difference between those battery cells and set the priority order of the voltage differences. Next, the controller 330 adjusts the voltage of the unbalanced battery unit according to the priority order. If two or more voltage differences have the same priority order, the controller 330 simultaneously controls the corresponding balancing circuit to adjust the voltage of the unbalanced battery cells. In another embodiment, if the battery management system 300 employs a chiller or fan to address thermal issues, the controller 330 does not need to determine and/or prioritize the voltage differences while adjusting all of the unbalanced battery cells.

If an abnormal state occurs, the controller 330 generates an early warning signal, electronic The control unit 340 reads the warning signal via the bus bar 350. The controller 330 can discern the abnormal state. The abnormal state includes, but is not limited to, an Over Voltage (OV) state, an Under Voltage (UV) state, or an Over Temperature (OT) state. When an abnormal state occurs, the controller 330 takes measures to protect the corresponding battery unit.

In one embodiment, if an overvoltage condition occurs, controller 330 controls the respective balancing circuit to suspend charging of the overvoltage battery unit. If an undervoltage condition occurs, the controller 330 controls the corresponding balancing circuit to suspend the discharge of the undervoltage battery unit. If an over-temperature condition occurs, the controller 330 controls the corresponding balancing circuit to reduce charging or discharging of the over-temperature battery cells, and even to suspend charging or discharging of the over-temperature battery cells. During operation of the battery management system 300, the number of battery cells in which an abnormal state occurs may vary. If an abnormal state occurs in a plurality of battery cells, the controller 330 can simultaneously control the corresponding balancing circuit, thereby improving the efficiency of the battery management system 300.

The electronic control unit 340 is coupled to the controller 330 via the bus bar 350 and processes the data from the controller 330. These materials include, but are not limited to, the voltage and/or temperature of the battery cells 301-360 and an early warning signal indicative of an abnormal state. Electronic control unit 340 provides software control for balance management of the battery pack. The electronic control unit 340 can also display the data and/or send the data to other devices (not shown) for further processing. Electronic control unit 340 is an optional configuration. In one embodiment, the electronic control unit 340 may be omitted for cost savings.

In one embodiment, referring to Figures 2C and 3, in active mode, The balancing unit 220C can replace the balancing circuits 321A-326A in the balancing unit 320. The first secondary coil is coupled to the first battery unit via a first switch, and the second secondary coil is coupled to the second battery unit via a second switch. The voltage of the first battery unit is greater than the voltage of the second battery unit, and when the voltage difference between the first battery unit and the second battery unit is greater than a threshold value, it is determined that an imbalance occurs. The controller 330 turns on the first switch and turns off the other switches, whereby the energy of the first battery unit is stored on the first secondary coil. In one embodiment, the controller 330 turns on the second switch and turns off the other switches, whereby the energy of the first secondary coil is transferred to the second secondary coil. In another embodiment, controller 330 turns on switch 290A and turns off the other switches, whereby the energy of the first secondary coil is transferred to primary coil 290. The battery cells 301-306 share the energy of the primary coil 290. The above process is repeatedly performed until a balance is reached between the first battery unit and the second battery unit.

Advantageously, controller 330 immediately monitors the voltage difference between battery cells 301-306 and controls the corresponding balancing circuit to adjust the voltage of the unbalanced battery cells. Therefore, the above measures can be taken to protect the unbalanced battery unit from damage. The controller 330 monitors the abnormal state of the battery cells 301-306 and takes the above measures to protect each battery cell to extend the battery cell life. Therefore, the life of the battery pack can be extended.

4 shows a battery management system 400 for a battery pack (eg, a lead acid battery pack) in accordance with another embodiment of the present invention. The battery management system 400 uses the balancing technique of the battery unit and the balancing technique of the battery module to extend the life of the battery pack, and if an imbalance occurs, the balancing speed can be increased. 4 is described in conjunction with FIGS. 2A, 2B, 2C, and 3. Elements in Figure 4 that are similar to those in the other figures have similar functions.

In one embodiment, the battery pack includes a plurality of battery modules 411-416. Each battery module includes a plurality of battery cells coupled in series (not shown in FIG. 4). Hereinafter, the battery module 411 will be described as an example. Each of the battery modules 411 is coupled to each of the balancing circuits 421 (not shown in FIG. 4). In one embodiment, the balancing unit 421 employs the structure of the balancing unit 320 of FIG. In another embodiment, the balancing unit 421 employs the structure of the balancing unit 220C of FIG. 2C.

The controller 431 is connected to the battery cells in the battery module 411 and monitors the parameters (e.g., voltage and/or temperature) of the battery cells. The controller 431 can function as a front end module. When an abnormal state occurs in one of the battery cells, the controller 431 controls the battery unit of the corresponding balance circuit protection state abnormality, and generates an early warning signal to be transmitted to the electronic control unit 441 via the bus bar 491. If an abnormal state occurs in a plurality of battery cells, the controller 431 can simultaneously control the corresponding balancing circuit to protect the corresponding battery cells, thereby improving the efficiency of the battery management system 400.

The controller 431 instantly detects the voltage of the battery cells in the battery module 411. When the battery cells in the battery module 411 are unbalanced, the controller 431 controls the corresponding balancing circuit to adjust the unbalanced battery by discharging or bypassing the corresponding battery cells or transferring energy between the corresponding battery cells. The voltage of the unit.

The electronic control unit 441 is coupled to the controller 431 via the bus bar 491 and processes the material from the controller 431. The electronic control unit 441 can display the material. In one embodiment, electronic control unit 441 transmits the data to electronic control unit 480 via coupler 451 for further processing. The coupler 451 can isolate the low voltage terminal (eg, the electronic control unit 480) And a high voltage terminal (eg, electronic control unit 441), thereby protecting electronic control unit 480 from high voltage damage.

In one embodiment, the controller 431 can be coupled to a battery unit of another battery module (not shown), such as a first battery unit in the battery module 412. Thereby, the controller 431 can simultaneously detect the voltage of the first battery unit in the battery module 421 and the voltage of the battery unit in the battery module 411. If an abnormal state occurs or an imbalance occurs between the first battery unit in the battery module 412 and the battery unit in the battery module 411, the controller 431 employs the above measures to solve the problem.

In one embodiment, if an imbalance occurs between the plurality of battery cells, the controller 431 controls the corresponding balancing circuit to adjust the voltage of the unbalanced battery cells according to the priority order of the battery cell voltage differences, thereby controlling the heat. In another embodiment, if a chiller or fan is used to solve the thermal problem, the controller 431 does not need to determine and/or prioritize the voltage differences while adjusting all of the unbalanced battery cells. If an abnormal state occurs in a plurality of battery cells, the controller 431 simultaneously takes the above measures to protect the corresponding battery cells, thereby improving the efficiency of the battery management system 400.

The controller 470 is coupled to the balancing unit 460, for example, a plurality of balancing circuits 461-466, and instantly detects the voltages of the battery modules 411-416. In one embodiment, the balancing circuits 461-466 employ the structure of the balancing circuit 220B of Figure 2B and perform the functions described above. In another embodiment, the balancing unit 460 employs the structure of the balancing unit 220C of Figure 2C and implements the functions described above. When an imbalance occurs between any two of the battery modules 411-416, the controller 470 controls the corresponding balancing circuits 461-466 to adjust the unbalanced battery modules. In one embodiment, such as If an imbalance occurs between the plurality of battery modules, the controller 470 controls the corresponding balancing circuit to adjust the voltage of the unbalanced battery module according to the priority order of the voltage difference between the battery modules, thereby controlling the heat. In another embodiment, if a chiller or fan is used to solve the thermal problem, the controller 470 does not need to determine and/or prioritize the voltage differences while adjusting all of the unbalanced battery modules.

Electronic control unit 480 is coupled to controller 470 via bus 482 and processes data from controller 470. Electronic control unit 480 can display the material and/or communicate the data to other devices (not shown) for further processing. Advantageously, the balancing technique of the battery unit and the balancing technique of the battery module can increase the efficiency of the battery management system 400 when an imbalance occurs. Thereby, the corresponding battery unit or the corresponding battery module can be protected from damage. Therefore, the life of the battery pack can be extended.

Electronic control units 441-446, balancing circuits 461-466, controller 470, and electronic control unit 480 in battery management system 400 are all optional configurations. In one embodiment, the balancing circuits 461-466 and controller 470 may be omitted, the corresponding functions of which are implemented by software. For example, the electronic control unit 480 reads the data of the controllers 431-436 via the electronic control units 441-446, and the controllers 431-436 take the above measures to solve various problems. In this case, the bus bar 482 can be omitted. In another embodiment, the electronic control units 441-446, the balancing circuits 461-466, the controller 470, and the electronic control unit 480 may be omitted, and the controllers 431-436 may take the above measures to solve various problems.

Figure 5 is a block diagram of a battery pack 500 (e.g., a lead acid battery pack) in accordance with one embodiment of the present invention. In one embodiment, as previously described The battery management system 200, 300 or 400 can be applied to the battery pack 500. The battery pack 500 includes a plurality of battery modules 501-506 coupled in series. Each battery module has two electrodes. The voltage of each of the battery modules 501-506 can be monitored via two electrodes. For example, the voltage of the battery module 501 is monitored via electrodes 530 and 531, and the voltage of the battery module 506 is monitored via electrodes 535 and 536.

In one embodiment, each battery module includes a plurality of battery cells 511-516 coupled in series. Each battery cell has two electrodes. The voltage of each of the battery cells 511-516 can be monitored via two electrodes. For example, the voltage of the battery unit 511 is monitored via the electrodes 520 and 521, and the voltage of the battery unit 516 is monitored via the electrodes 525 and 526.

6 is a flow chart 600 showing the operation of a battery management system for a battery pack in accordance with one embodiment of the present invention. Figure 6 is described in conjunction with Figure 4.

In step 601, controllers 431-436 monitor the parameters (e.g., voltage and/or temperature) of the battery cells in battery modules 411-416. Controller 470 monitors parameters (e.g., voltage and/or temperature) of battery modules 411-416.

In step 610, if an abnormal condition occurs in the battery unit, the controllers 431-436 take measures to protect the corresponding battery unit. If an overvoltage condition occurs, the controllers 431-436 control the respective balancing units 421-426 to suspend charging of the overvoltage battery unit. If an undervoltage condition occurs, the controllers 431-436 control the respective balancing units 421-426 to suspend the discharge of the undervoltage battery cells. If an over-temperature condition occurs, the controllers 431-436 control the respective balancing units 421-426 to reduce charging or discharging of the over-temperature battery cells, or to suspend charging or discharging of over-temperature battery cells. Advantageously, The controllers 431-436 can simultaneously control the respective balancing units 421-426, thereby increasing the efficiency of the battery management system 400.

In step 620, controllers 431-436 calculate the voltage difference ΔV _C between the battery cells and compare ΔV _C with the threshold V _THC . If ΔV _{C is} greater than V _THC , it is determined that the battery unit is unbalanced. In one embodiment, to control the heat, the controllers 431-436 control the respective balancing circuits of the balancing units 411-416 to adjust the voltage of the unbalanced battery cells according to the priority order of the voltage differences until equilibrium. In another embodiment, if a cooler or fan is used to solve the thermal problem, the controllers 431-436 can simultaneously adjust all of the unbalanced batteries.

More specifically, in the passive mode, the corresponding balancing circuit discharges a battery cell having a higher voltage during discharge or bypasses a battery cell having a higher voltage during charging. Discharge or bypass after one or more cycles until ΔV _C falls to the threshold V _THC . In the active mode, a transformer (not shown) transfers the energy of the battery unit having a higher voltage to the battery unit having a lower voltage until ΔV _C falls to the threshold value V _THC .

In step 630, the controller 470 calculates a voltage difference ΔV _M between the battery modules and compares ΔV _M with the threshold value V _THM . If ΔV _{M is} greater than V _THM , it is determined that the battery module is unbalanced. In order to control the heat, the controller 470 controls the respective balancing circuits 461-466 to adjust the voltage of the unbalanced battery module according to the priority order of the voltage difference until the balance is reached. In another embodiment, a cooler or fan is used to solve the thermal problem, and the controller 470 can simultaneously adjust all of the unbalanced battery modules.

More specifically, in the passive mode, the corresponding balancing circuit discharges the battery module having a higher voltage during the discharging process or bypasses the battery module having a higher voltage during the charging process. After one or more cycles, until ΔV _M falls to the threshold V _THM . In the active mode, a transformer (not shown) transfers the energy of the battery module having a higher voltage to the battery module having a lower voltage until ΔV _M falls to the threshold value V _THM .

Advantageously, the balancing technique can be used to simultaneously adjust the voltages of the plurality of battery cells and/or battery modules in accordance with the prioritization of the voltage differences, thereby increasing the efficiency of the battery management system 400.

7 is a block diagram of an electric vehicle 700 (e.g., an electric vehicle) employing a battery management system 702 of one embodiment of the present invention. Figure 7 is described in conjunction with other figures. Electric vehicle 700 includes other known components in addition to the components shown.

In one embodiment, electric vehicle 700 includes a lead acid battery pack 701, a battery management system 702, a controller circuit 703, and an engine 704. However, those of ordinary skill in the art should be able to understand that the battery pack of the electric vehicle 700 is not limited to the lead-acid battery pack 701, but may be other types of battery packs. The battery management system 702 can be the structure of the battery management system 200, 300 or 400 as previously described. In one embodiment, battery management system 702 and lead acid battery pack 701 can be integrally packaged. Controller circuit 703 controls the supply of power to engine 704 by lead-acid battery pack 701. The engine 704 drives the electric vehicle 700.

Advantageously, the battery management system 702 uses a balancing technique to instantly balance a plurality of battery cells and/or a plurality of battery modules, thereby protecting the lead acid battery pack 701 from damage if an imbalance occurs. Therefore, the life of the lead-acid battery pack 701 can be extended and the reliability of the electric vehicle 700 can be enhanced.

Figure 8 is a block diagram of a battery management system 800 for a battery pack (e.g., a lead acid battery pack) in accordance with one embodiment of the present invention. An inter-cell controller 850 can be used to extend the life of the battery pack and reduce the cost of the battery pack. Figure 8 is described in conjunction with Figure 2B.

In one embodiment, the battery pack includes one or more battery modules coupled in series. In the example of FIG. 8, the battery pack includes two battery modules 841 and 842 coupled in series. As shown in FIG. 8, the battery module 841 includes six battery units 801-806, and the battery module 842 includes six battery units 807-812. One of the battery cells 801-812 is connected to a balancing circuit. In one embodiment, each of the balancing circuits 821-832 may employ the structure of the balancing circuit 220B of FIG. 2B. More specifically, the balancing circuit includes a resistor 281 and a switch 282 coupled in series. However, the number of battery cells, battery modules, and balancing circuits is not limited thereto, and the number thereof may vary depending on different applications. The following is a detailed description of a 2 volt battery unit.

The inter-cell controller 850 is connected to the balancing circuits 821-832 and the battery cells 801-812. The inter-cell controller 850 monitors parameters (eg, voltage, current, and/or temperature) of the battery cells 801-812, and controls the balancing circuits 821-832 to adjust the voltage of the unbalanced battery cells when an imbalance occurs, and when an abnormality occurs The protection measures are activated when the status is in progress. In one embodiment, the inter-cell controller 850 monitors the voltages of the battery cells 801-812 and calculates the voltage difference between any two of the battery cells 801-812 in the battery modules 841 and 842. In this case, the inter-cell controller 850 can determine whether an imbalance occurs between any two of the battery cells, and even determine whether the battery cells in the different battery modules are unbalanced. Thereby, the efficiency of balancing the battery cells is improved. When an imbalance occurs between any two of the battery cells 801-812, the inter-cell controller 850 controls the respective balancing circuits 821-832 to adjust the voltage of the battery cells. In one embodiment, an imbalance is detected by the inter-cell controller 850. For example, the inter-cell controller 850 sets the threshold value V _TH1 to determine whether or not an imbalance has occurred. If the voltage difference between any two of the battery cells 801-812 is greater than the threshold value _VTH1 , the inter-cell controller 850 determines that an imbalance has occurred. The inter-cell controller 850 activates a corresponding balancing circuit to adjust the voltage of the unbalanced battery cells.

For example, the inter-cell controller 850 detects that the voltages of the battery cells 801 and the battery cells 807 in the battery module 842 in the battery module 841 are V ₁ and V ₂ , respectively (for example, 2.1 volts and 2.0 volts, respectively). If the voltage difference ΔV ₁₂ between the battery cells 801 and 807 is greater than the threshold value V _TH1 (for example, 0.02 volts), the inter-cell controller 850 determines that an imbalance occurs between the battery cells 801 and 807. In this case, the inter-cell controller 850 controls the balancing circuits 821 and 827 to adjust the voltages of the battery cells 801 and 807 until the balance between the battery cells 801 and 807 is reached, that is, the voltage difference between the battery cells 801 and 807. V _{12 is} no longer greater than the threshold V _TH1 . In one embodiment, in the passive mode, balancing circuit 821 discharges battery unit 801 during discharge or bypasses battery unit 801 during charging until ΔV ₁₂ falls to threshold V _TH1 . The balancing circuits 821-832 may employ the structure of the balancing circuit 220B of FIG. 2B. The inter-cell controller 850 sends a control signal to the switch 282 in the balancing circuit 821, which is continuously turned on for one or more cycles. Thus, during discharge, the discharge current flows through the resistor 281 and the switch 282 in the balancing circuit 821. Therefore, V _{1 is} reduced. During charging, the charging current flows through the resistor 281 and the switch 282 in the balancing circuit 821. Once ΔV _{12 is} no longer greater than V _TH1 , the battery cells 801 and 807 are balanced, and the inter-cell controller 850 turns off the switch 282 in the balancing circuit 821, thereby stopping the discharge or bypass of the battery cell 801.

If an imbalance occurs between the plurality of battery cells, the inter-cell controller 850 calculates a voltage difference between the plurality of battery cells, and sets a priority order for the voltage difference. In one embodiment, the maximum voltage difference is set to the highest priority and the minimum voltage difference is set to the lowest priority, ie, the greater the voltage difference, the higher the priority. The inter-cell controller 850 adjusts the unbalanced battery cells in accordance with the priority order of the voltage differences. If two or more voltage differences have the same priority order, the inter-cell controller 850 simultaneously controls the corresponding balancing circuit to adjust the voltage of the unbalanced battery cells. In another embodiment, if a chiller or fan is used to solve the thermal problem, the inter-cell controller 850 does not need to determine and/or prioritize the voltage differences while adjusting the voltage of all unbalanced battery cells.

In addition, the inter-cell controller 850 monitors parameters (eg, current, voltage, and temperature) of each of the battery cells 801-812. The inter-cell controller 850 can also detect an abnormal state including, but not limited to, an overvoltage state, an undervoltage state, an overtemperature state, a Discharge Over Current (DOC) state, and a charging overcurrent. (Charge Over Current, referred to as COC) status. If the abnormal state described above occurs, the inter-cell controller 850 generates a control signal to turn off the discharge switch 861 in the battery pack, and/or generates a control signal to turn off the charge switch 862 in the battery pack, thereby suspending the battery cells 801-812. Discharge or Charging.

In one embodiment, the inter-cell controller 850 monitors the voltage of each of the battery cells 801-812 and compares these voltages to a threshold V _OV or V _UV set by the inter-cell controller 850, To determine whether an overvoltage condition or an undervoltage condition has occurred; if one of the battery cell voltages is greater than a predetermined threshold value V _OV , it is determined that an overvoltage condition occurs, and the inter-cell controller 850 generates a control signal to turn off The charging switch 862 further suspends charging of the battery cells 801-812; if one of the battery cell voltages is less than a predetermined threshold _VUV , it is determined that an undervoltage condition occurs, and the inter-cell controller 850 generates control The signal turns off the discharge switch 861, which in turn stops the discharge of the battery cells 801-812. The battery controller 850 can also monitor the voltage of the detecting resistor 872, and compare the voltage of the detecting resistor 872 with the threshold V _COC or V _DOC set by the controller 850 in the battery to determine whether a charging overcurrent condition or a discharge has occurred. In the charging state, if the voltage of the detecting resistor 872 is greater than the predetermined threshold value V _COC during charging, it is determined that the charging overcurrent state occurs, and the inter-cell controller 850 generates a control signal to turn off the charging switch 862, thereby stopping the battery unit Charging of 801-812; during the discharging process, if the voltage of the detecting resistor 872 is greater than the predetermined threshold value V _DOC , it is determined that the discharging overcurrent state occurs, and the inter-cell controller 850 generates a control signal to turn off the discharging switch 861, thereby suspending Discharge of battery cells 801-812. The inter-cell controller 850 can also monitor the voltage of the thermistor (not shown in FIG. 8) coupled to each of the battery cells 801-812, and the voltage of the thermistor and the inter-cell controller 850 The set threshold value V _OT is compared to determine whether an over temperature condition occurs; if the voltage of the thermistor is greater than the predetermined threshold value V _OT , it is determined that an over temperature condition occurs, and the inter-cell controller 850 generates a control signal to turn off. The discharge switch 861 and/or the charge switch 862, in turn, suspends discharge and/or charging of the battery cells 801-812.

Advantageously, the inter-cell controller 850 is capable of monitoring the voltage of the battery cells 801-812 in the battery pack, even calculating the voltage difference between any two of the different battery modules 801-812, and controlling the corresponding balancing circuit Adjust the voltage of the unbalanced battery unit. In addition, the inter-cell controller 850 can detect an abnormal state of the battery cells 801-812 and generate a control signal to turn off the discharge switch 861 and/or the charge switch 862, thereby suspending discharge and/or charging of the batteries 801-812, To protect the battery unit from damage. Therefore, the life of the battery pack is extended.

Figure 9 is a block diagram of a battery management system 900 for a battery pack (e.g., a lead acid battery pack) in accordance with one embodiment of the present invention. Figure 9 is described in conjunction with Figures 2B and 3.

In one embodiment, the battery pack includes a plurality of battery modules. Taking FIG. 9 as an example, the battery module includes six battery cells 901-906 coupled in series. Each of the battery cells 901-906 is coupled to one of the balancing circuits 921A-926A, respectively. Controller 930 is coupled to battery cells 901-906 and balancing circuits 921A-926A and monitors the voltage of battery cells 901-906. The same elements as those in FIG. 3 have similar functions and will not be described again.

In one embodiment, the module overvoltage detection circuit 960 is coupled to both ends of the battery module and monitors the voltage of the battery module in the battery pack. The module overvoltage detection circuit 960 is also coupled to the module overvoltage balancing circuit 962. The voltage balance circuit 962 is coupled to both ends of the battery module. In one embodiment, the module overvoltage balancing circuit 962 employs the configuration of the balancing circuit 220B of FIG. 2B to reduce the cost of the battery pack. More specifically, the module overvoltage balancing circuit 962 includes the series coupled resistor 281 and switch 282 shown in FIG. 2B.

In one embodiment, the module overvoltage detection circuit 960 monitors the voltage of the battery module and determines whether the battery module has an overvoltage condition. More specifically, the module overvoltage detection circuit 960 sets the predetermined threshold _{VTHMOV of the} 12 volt battery module to, for example, 14.76 volts. The module overvoltage detection circuit 960 monitors the voltage of the battery module, compares the voltage of the battery module with a predetermined threshold V _THMOV , and determines that the battery module occurs when the voltage of the battery module is greater than a predetermined threshold V _THMOV . Overvoltage condition. When the battery module is in an overvoltage state, the module overvoltage detection circuit 960 generates a control signal and sends it to the module overvoltage balancing circuit 962 to turn on the switch 282 in the module overvoltage balancing circuit 962. Thereby, a bypass including the switch 282 and the resistor 281 is established at both ends of the battery module. In this case, when the charging mode is suspended, the module overvoltage balancing circuit 962 can discharge the battery module or bypass the battery module during charging. Discharge or bypass after one or more cycles until the voltage of the battery module is no longer greater than the predetermined threshold V _THMOV .

The module overvoltage detection circuit 960 can be used to monitor battery modules including different numbers of battery cells. Therefore, the predetermined threshold V _THMOV can be set according to the number of battery cells in the battery module. For example, the voltage of the battery module including 12 battery cells is 24 volts, and the predetermined threshold V _{THMOV is} set to 26 volts. In addition, the resistance of the resistor 281 in the module overvoltage balancing circuit 962 can be set according to the number of battery cells in the battery module to adjust the bypass current, thereby improving the efficiency of the battery management system 900.

Advantageously, the module overvoltage balancing circuit 962 adjusts the voltage of the battery module while the balancing circuit 921A-926A adjusts the battery voltage in the battery module. Thereby, the response speed of the battery management system 900 and the efficiency of the battery management system 900 can be improved, and the life of the battery pack can be extended.

Figure 10 is a flow chart 1000 showing the operation of a battery management system for a battery pack (e.g., a lead acid battery pack) in accordance with one embodiment of the present invention. Figure 10 is described in conjunction with Figure 9.

In step 1001, as shown in FIG. 9, the controller 930 monitors parameters (eg, voltages of the plurality of battery cells 901-906 in the battery module), and the module overvoltage detection circuit 960 monitors the voltage of the battery module V _M .

In step 1100, the module overvoltage detection circuit 960 determines whether an overvoltage condition has occurred in the battery module. For example, the module overvoltage detection circuit 960 monitors the voltage V _{M of the} battery module and compares V _M to a predetermined threshold V _THMOV . When V _{M is} greater than the predetermined threshold V _THMOV , it is determined that the battery module is in an overvoltage state. The module overvoltage detection circuit 960 controls the module overvoltage balancing circuit 962 to adjust the voltage V _{M of the} battery module. More specifically, the module overvoltage balancing circuit 962 discharges or bypasses the battery module until the battery module voltage V _M falls to a predetermined threshold V _THMOV . In addition, the predetermined threshold V _THMOV can be set according to the number of battery cells of the battery module, and the overvoltage state of the battery module can be detected regardless of the number of battery cells in the battery module. The resistance of the resistor 281 in the module overvoltage balancing circuit 962 is set according to the number of battery cells in the battery module, thereby adjusting the bypass current, and improving the efficiency of the battery management system 900.

In step 1200, the controller 930 calculates a voltage difference ΔV _CELL of any two of the plurality of battery cells and compares the voltage difference ΔV _CELL with a predetermined threshold V _THCELL . When ΔV _{CELL is} greater than the predetermined threshold V _THCELL , an imbalance occurs between the two battery cells. The controller 930 controls the corresponding balancing circuit to adjust the voltage of the unbalanced battery unit.

More specifically, the corresponding balancing circuit discharges a battery cell having a higher voltage during discharging or bypasses a battery cell having a higher voltage during charging. Discharge or bypass after one or more cycles until ΔV _CELL drops to a predetermined threshold V _THCELL .

Advantageously, the plurality of balancing circuits 921A-926A and the module overvoltage balancing circuit 962 can simultaneously adjust the voltages of the plurality of battery cells and/or battery modules, thereby increasing the efficiency of the battery management system 900.

Accordingly, embodiments of the present invention provide a battery management system for a battery pack (eg, a lead acid battery pack) that includes a plurality of controllers for detecting voltages of a plurality of battery cells coupled in series. If an imbalance occurs between the battery cells, the controller can control a plurality of balancing circuits to adjust the voltage of the battery cells. If the battery unit is in an abnormal state, the controller takes measures to protect the battery unit. Thanks to the balancing technology, the battery unit is protected from damage. Therefore, the efficiency of the battery management system is improved and the life of the battery pack is extended.

An embodiment of the present invention further provides a battery management system including a controller for detecting a voltage of a battery module coupled in series. If an imbalance occurs between the battery modules, the controller controls a plurality of balancing circuits to adjust the voltage of the battery module. Due to the balancing technology, the battery module is protected from damage. Therefore, the efficiency of the battery management system is improved and extended The life of the battery pack.

The present invention further provides a method of solving the problem of increasing the output voltage of a plurality of battery modules. One embodiment of the present invention provides a comparator or a module control unit (MCU) for each battery module. The comparator or module control unit of the first battery module compares the output voltage of the first battery module with the output voltage of the first battery module and the second battery module. If a part of the output voltage of the first battery module is greater than a portion of the output voltage sum of the first battery module and the second battery module, starting the first module balancing circuit corresponding to the first battery module, and terminating the corresponding a second module balancing circuit of the second battery module; if a portion of the output voltage sum of the first battery module and the second battery module is greater than an output voltage of the first battery module, starting corresponding to the second battery module The second module balancing circuit of the group simultaneously terminates the first module balancing circuit corresponding to the first battery module.

As shown in Figures 11 and 12, in one embodiment, the battery management system includes a plurality of battery modules 1102-1108. Although four battery modules are shown in FIG. 11 and FIG. 12, other numbers of battery modules may be used in other embodiments, and are not limited thereto. As shown in FIG. 11, the battery module 1102 includes a plurality of battery cells 1110-1120 coupled in series. As shown in FIG. 12, a plurality of battery modules 1102-1108 are also coupled in series. As described above, each of the battery cells 1110-1120 in the battery module 1102 is coupled to a corresponding balancing circuit 1134-1144. As shown in FIG. 11, the battery module 1102 further includes a battery balance control circuit 1158 that controls the balance of the battery cells 1110-1120 in the battery module 1102 through the balancing circuits 1134-1144. Each battery module 1102-1108 in Figure 12 A similar element as shown in Figure 11 is included. For example, the battery module 1104 includes a plurality of battery cells 1122-1132 coupled in series, a balancing circuit 1146-1156 coupled to each of the battery cells 1122-1132, and a battery module 1104 through the balancing circuit 1146-1156. A balanced battery balance control circuit 1160 for each of the battery cells 1122-1132.

In one embodiment, as shown in FIG. 11, the battery module 1102 includes a module control unit 1162. The module control unit 1162 can adjust the output voltage of the battery module 1102 through the control module balancing circuit 1164. The control unit 1162 can also adjust the output voltage sum of the battery module 1102 and the battery module 1104 through the control module balancing circuit 1166. As shown in FIG. 11, the module balancing circuit 1166 adjusts the output voltages of the battery module 1102 and the battery module 1104 by adjusting the output voltages of the battery module 1102 and the battery module 1104. As shown in FIG. 11 and FIG. 12 , the module balancing circuit 1164 is coupled to the positive and negative poles of the battery module 1102 , and the module balancing circuit 1166 is coupled to the anode of the battery module 1104 and the cathode of the battery module 1102 , and the battery Modules 1102 and 1104 are coupled in series.

As described above, the module balancing circuit 1164 and the module balancing circuit 1166 are controlled by the module control unit 1162, and the module balancing circuits 1164 and 1166 can adjust the battery modules 1102 and 1104 coupled thereto in the passive mode. The output voltage. As described above, in the passive mode, the module balancing circuits 1164 and 1166 can discharge the battery module coupled thereto during discharge or bypass the battery module coupled thereto during charging. As described above, the module balancing circuits 1164 and 1166 can employ the balancing unit 220C described in FIG. 2C, which can balance the battery modules in the active mode.

In one embodiment, as shown in FIG. 11, the module control unit 1162 includes a pair of analog/digital inputs (A/D 1 and A/D 2) and a pair of outputs (I/O 1 and I/O). 2). Output I/O 1 and I/O 2 are used to control module balancing circuits 1166 and 1164, respectively. Inputs A/D 1 and A/D 2 receive a portion of the output voltages of battery modules 1102 and 1104, a portion of which is determined by voltage divider resistors R1/R2 and R3/R4. The voltage dividing resistor R1/R2 is formed by selecting a suitable resistor to provide a voltage dividing ratio, thereby reducing the output voltage of the battery module 1102 to the input range parameter of the input terminal A/D1. Similarly, the voltage dividing resistor R3/R4 is formed by selecting an appropriate resistor to provide a voltage dividing ratio, thereby reducing the output voltage of the battery modules 1102 and 1104 to the input range parameter of the input terminal A/D 2 .

In one embodiment, the voltage dividing resistors R3 and R4 can provide a voltage dividing ratio, thereby reducing the output voltage of the battery modules 1102 and 1104 to be approximately equal to the voltage values provided by the voltage dividing resistors R1 and R2. The output voltage of the module 1102 can be compared to the output voltages of the battery modules 1102 and 1104. In one embodiment, as shown in FIG. 11, each of the battery modules 1102 and 1104 includes six battery cells 1110-1120 and 1122-1132, respectively, and the voltage value of each battery cell is approximately 2 volts, thus, each The voltage module has an output voltage of 12 volts. Therefore, if the voltage divider ratio of the voltage divider R1/R2 is 2:1, in order to provide approximately equal voltage output, the voltage divider ratio of the voltage divider R3/R4 should be 4:1. In other words, the voltage dividing resistor R1/R2 (the voltage dividing ratio is 2:,) reduces the output voltage of the battery module 1102 from 12 volts to 6 volts, and the voltage dividing resistor R3/R4 (the voltage dividing ratio is 4:1). The output voltages of modules 1102 and 1104 are reduced from 24 volts to 6 volts. The partial pressure ratio described above is merely exemplary In other embodiments, different voltage division ratios may be selected according to different design requirements to meet the parameter requirements of the analog/digital input terminal, and are not limited thereto.

In one embodiment, as shown in FIG. 11, the module control unit 1162 receives the output voltage of the battery module 1102 and the output voltages of the battery modules 1102 and 1104 and (provided by the voltage dividing resistors R1/R2 and R3/R4) And compare them. If the output voltage value of the reduced battery module 1102 is greater than the output voltage sum of the reduced battery modules 1102 and 1104, the module balancing circuit 1164 corresponding to the battery module 1102 is activated. However, if the output voltages of the reduced battery modules 1102 and 1104 are greater than the output voltage of the reduced battery module 1102, the module balancing circuit 1166 corresponding to the battery modules 1102 and 1104 coupled in series is activated.

In another embodiment, to compare the output voltages of the battery modules 1102 and 1104, the module control units 1162 and 1168 shown in FIG. 11 do not need to be similar to the voltages of the inputs A/D 1 and A/D 2 . equal. Instead, control module control units 1162 and 1168 can be selectively programmed such that inputs A/D 1 and A/D 2 of module control unit 1162 receive input voltages of different values and compare. For example, the input terminals A/D 1 and A/D 2 of the module control unit 1162 can be received from the voltage dividing resistor R1/R2 (the voltage dividing ratio is 6:1, and the output voltage of the battery module 1102 is 12 volts). The input voltage of 2 volts and the receiving voltage from the voltage dividing resistor R3/R4 (the voltage dividing ratio is 12:1, the output voltage of the battery modules 1102 and 1104 is 36 volts, and the output voltage of the battery module 1104 is 24 volts) The input voltage is 3 volts and can still be judged to be approximately equal after the reduced input voltage. When used When the battery module with different but known battery capacity replaces the original battery module, the above programming adjustment can be used without replacing the original voltage dividing resistors (R1/R2 and R3/R4). Instead, module control unit 1162 can be reprogrammed to account for voltage changes.

As shown in FIG. 11 and FIG. 12, when the module control unit 1162 in the battery module 1102 compares the output voltage of the battery module 1102 with the output voltage of the battery modules 1102 and 1104, the module control in the battery module 1104. Unit 1168 compares the output voltage of battery module 1104 with the output voltage of battery modules 1104 and 1106. Thus, in an exemplary embodiment, the output voltage of the battery module 1104 can be balanced by the module balancing circuit 1170 in the battery module 1104 and the module balancing circuit 1166 in the battery module 1102 (the module balancing circuit 1166 balances the battery). The output voltages of the modules 1104 and 1102 are simultaneously adjusted.

In one embodiment, as shown in FIG. 13, module control units 1162 and 1168 as shown in FIG. 11 are replaced by comparators 1362 and 1368, respectively. Module control units 1162 and 1168 have high accuracy and flexibility, while comparators 1362 and 1368 have relatively low cost. Comparators 1362 and 1368 have similar applications to the module control units 1162 and 1168 described above. In one embodiment, in order for the comparator 1362 to provide an appropriate comparison output, the voltage division ratios of the voltage dividing resistors (R1/R2 and R3/R4) should be appropriately set, thereby making the comparator inputs (input1 and input2) The inputs are approximately equal. As mentioned earlier, module control units 1162 and 1168 have greater flexibility and do not require input voltages to be approximately equal, but require programmed control to compare different voltage values.

Another embodiment shown in Figure 14, the module control unit or ratio The comparator can also receive additional inputs, such that the module control unit or comparator can compare the output voltage of the battery module 1102 with the output voltages of the battery modules 1102 and 1104, the voltages of the battery modules 1102-1106, and others. The additional input voltage. By providing an additional voltage divider resistor (and appropriate program control of the module control unit) as shown in Figure 11, an additional voltage output is obtained, which in turn allows the module control unit or comparator to compare it. As shown in FIG. 14, the additional module balancing circuit can output the voltage of the battery module 1102, the output voltage of the battery modules 1102 and 1104, the output voltage of the battery modules 1102-1106, and the battery module 1102-1108. The output voltage is adjusted. As described above, based on the comparison of the output voltage of the battery module 1102, the output voltage of the battery modules 1102 and 1104, the output voltage of the battery modules 1102-1106, and the output voltage of the battery modules 1102-1108, As a result, the module balancing circuit is selected and activated. In Fig. 14, more additional module balancing circuits can be applied to the battery modules 1104, 1106, etc.; in order to make Figure 14 more compact, these additional module balancing circuits are not all shown.

The battery management system and the balancing method of the present invention are more efficient than the prior art, and the voltage of the battery unit and/or the battery module is adjusted when the battery pack is unbalanced. Therefore, the efficiency of the battery pack can be improved and the life of the battery pack can be extended.

The above detailed description and the accompanying drawings are only typical embodiments of the invention. It is apparent that various additions, modifications and substitutions are possible without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood by those skilled in the art that the present invention can be used in practical applications according to specific environmental and working requirements without departing from the invention guidelines. Construction, layout, proportions, materials, elements, components, and other aspects have changed. Therefore, the embodiments disclosed herein are intended to be illustrative and not restrictive, and the scope of the invention is defined by the appended claims

The technical solutions of the present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments to make the features and advantages of the present invention more obvious. among them:

100‧‧‧ lead-acid battery pack

101-104‧‧‧ battery module

111-116‧‧‧ battery unit

120‧‧‧electrode

129‧‧‧electrode

200‧‧‧Battery Management System

211-216‧‧‧ battery module

220‧‧‧balance unit

221-226‧‧‧Balance circuit

230‧‧‧ Controller

240‧‧‧Electronic Control Unit

250‧‧‧ busbar

220B‧‧‧balance circuit

281‧‧‧ Circuitry

282‧‧‧ switch

220C‧‧‧balance unit

290‧‧‧ primary coil

290A‧‧‧ switch

291-296‧‧‧second coil

291A-296A‧‧‧ Switch

300‧‧‧Battery Management System

301-306‧‧‧ battery unit

310‧‧‧ battery module

311-316‧‧‧resistance

320‧‧‧balance unit

321-326‧‧‧Switch

321A-326A‧‧‧balance circuit

330‧‧‧ Controller

340‧‧‧Electronic Control Unit

350‧‧ ‧ busbar

400‧‧‧Battery Management System

411-416‧‧‧ battery module

421-426‧‧‧Balance unit

431-436‧‧‧ Controller

441-446‧‧‧Electronic Control Unit

451-456‧‧‧ Coupler

460‧‧‧balance unit

461-466‧‧‧balance circuit

470‧‧‧ Controller

480‧‧‧Electronic Control Unit

482‧‧ ‧ busbar

491-496‧‧ ‧ busbar

500‧‧‧Battery Pack

501-506‧‧‧ battery module

511-516‧‧‧ battery unit

520-526‧‧‧electrode

530-536‧‧‧electrode

600‧‧‧Operation flow chart

601‧‧ steps

610-630‧‧‧Steps

700‧‧‧Electric vehicles

701‧‧‧ lead-acid battery pack

702‧‧‧Battery Management System

703‧‧‧Controller circuit

704‧‧‧ engine

800‧‧‧Battery Management System

801-812‧‧‧ battery unit

821-832‧‧‧balanced circuit

841-842‧‧‧ battery module

850‧‧‧Battery unit controller

861‧‧‧Discharge switch

862‧‧‧Charge switch

872‧‧‧Detection resistance

900‧‧‧Battery Management System

901-906‧‧‧ battery unit

921A-926A‧‧‧balance circuit

930‧‧‧ Controller

960‧‧‧Modular overvoltage detection circuit

962‧‧‧Modular overvoltage balancing circuit

1000‧‧‧Operation flow chart

1001‧‧‧Steps

1100-1200‧‧ steps

1102-1108‧‧‧Battery module

1110-1132‧‧‧ battery unit

1134-1156‧‧‧balance circuit

1158-1160‧‧‧Battery balance control circuit

1162‧‧‧Modular Control Unit

1164-1166‧‧‧Module balancing circuit

1168‧‧‧Modular Control Unit

1170-1172‧‧‧Module balancing circuit

1362‧‧‧ comparator

1368‧‧‧ comparator

The technical method of the present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments to make the features and advantages of the present invention more obvious. 1 is a block diagram of a conventional lead-acid battery pack; FIG. 2A is a schematic diagram of a battery pack management system of a battery pack according to an embodiment of the present invention; and FIG. 2B is a view of a battery pack according to the present invention; FIG. 2C is a structural diagram of a balancing unit in a battery management system of a battery pack according to an embodiment of the present invention; FIG. 2C is a structural diagram of a balancing unit in a battery management system of a battery pack according to an embodiment of the present invention; A schematic diagram of a battery management system of a battery pack according to another embodiment of the present invention; FIG. 4 is a schematic diagram of a battery management system of a battery pack according to another embodiment of the present invention; FIG. 6 is a flow chart showing the operation of the battery pack management system of the battery pack according to an embodiment of the present invention; FIG. 7 is a flowchart showing the operation of the battery pack management system of the battery pack according to an embodiment of the present invention; Schematic diagram of an electric vehicle; 8 is a schematic diagram of a battery management system of a battery pack according to an embodiment of the present invention; and FIG. 9 is a schematic diagram of a battery management system of a battery pack according to an embodiment of the present invention; FIG. 11 is a block diagram showing a battery management system for a battery pack according to an embodiment of the present invention; FIG. 11 is a block diagram of a battery management system for a battery pack according to an embodiment of the present invention; 1 is a block diagram of a plurality of batteries in accordance with an embodiment of the present invention; FIG. 13 is a block diagram of a battery management system for a battery pack in accordance with another embodiment of the present invention; and FIG. A block diagram of a battery management system for a battery pack in accordance with another embodiment of the present invention.

1102‧‧‧ battery module

1104‧‧‧ battery module

1110-1132‧‧‧Battery

1134-1156‧‧‧balance circuit

1158‧‧‧Battery balance control circuit

1160‧‧‧Battery balance control circuit

1162‧‧‧Modular Control Unit

1164‧‧‧Module balancing circuit

1166‧‧‧Module balancing circuit

1168‧‧‧Modular Control Unit

1170‧‧‧Module balancing circuit

1172‧‧‧Module balancing circuit

Claims (17)

A battery management system includes: a plurality of battery modules; a plurality of first balancing units, the plurality of first balancing units coupled to the plurality of battery modules; a plurality of second balancing units, the plurality of second The balancing unit is coupled to the plurality of battery modules, wherein each of the first balancing unit and each of the second balancing units are respectively coupled to each of the battery modules; and a plurality of controllers, the plurality of controls The controller is coupled to the plurality of battery modules, wherein each of the controllers is coupled to each of the battery modules, and a first controller of the plurality of controllers determines a first battery module The first controller controls a first balancing unit of the first battery module to adjust the first battery module when an output voltage is greater than an output voltage of the first battery module and a second battery module The output voltage, and wherein the first controller determines that the output voltage of the first battery module and the second battery module is greater than the output voltage of the first battery module, the first control Controlling a second balance sheet in the first battery module Adjusting the output voltage of the first battery module and the second battery module, wherein the first controller compares a reduced output voltage of the first battery module with the first battery module and the first The second battery module has a lower output voltage and a lower output voltage. The battery management system of claim 1, wherein the second balancing unit of the first battery module adjusts the output voltage of the first battery module and the second battery module to Adjustment The output voltage of the second battery module. The battery management system of claim 2, wherein the first battery module further comprises: a first voltage divider having a first voltage dividing ratio; and a first voltage dividing ratio a second voltage divider, the second voltage dividing ratio is selected to reduce the output voltage of the first battery module and the second battery module to be approximately equal to an output voltage of the first voltage divider, the first The output voltage of a voltage divider is the reduced output voltage of the first battery module, and an output voltage of the second voltage divider is the output voltage of the first battery module and the second battery module with. The battery management system of claim 3, wherein the first voltage dividing ratio of the first voltage divider is selected to reduce the output voltage of the first battery module to one of the first controllers. An input voltage range of the first analog/digital converter; selecting the second voltage dividing ratio of the second voltage divider to reduce the output voltage of the second voltage divider to be approximately equal to the first partial voltage The output voltage of the device. The battery management system of claim 3, wherein the output voltage of each of the battery modules is approximately equal. The battery management system of claim 5, wherein the second partial pressure ratio of the second voltage divider is twice the first partial pressure ratio. A battery management system according to claim 5, wherein each of the battery modules has the same number of battery cells, each battery cell having an approximately equal output voltage value. The battery management system of claim 3, wherein an output voltage of at least one of the plurality of battery modules When the output voltages of the other battery modules are not equal, the voltage divider reduces the output voltage of the at least one of the plurality of battery modules, thereby causing the reduced output voltage to be compared with another In comparison, an output voltage of a battery module is approximately equal. The battery management system of claim 1, wherein the first controller compares the first voltage when the output voltage of the first battery module is not equal to the output voltage of the second battery module The reduced output voltage of the battery module is equal to the output voltage of the first battery module and the second battery module. A method for balancing a plurality of battery modules in a battery pack, comprising: comparing an output voltage of a first battery module with an output voltage of the first battery module and a second battery module; and when the first Adjusting the output voltage of the first battery module when the output voltage of the battery module is greater than the output voltage, and wherein, when the output voltage is greater than the output voltage of the first battery module, adjusting the output voltage The output voltage sum, wherein the comparing the output voltage of the first battery module with the output voltage comprises: comparing a reduced output voltage of the first battery module with the first battery module and the second The battery module is lowered after the output voltage and. The method of claim 10, wherein the step of adjusting the output voltage sum comprises: adjusting the output voltage of the second battery module. The method of claim 10, wherein the reduced output voltage and current of the first battery module and the second battery module are The reduced output voltage of the first battery module is approximately equal. The method of claim 12, wherein the output voltage of each of the battery modules is approximately equal. A battery management system includes: a first comparing device, comparing an output voltage of a first battery module with an output voltage of the first battery module and a second battery module; and an adjusting device Adjusting the output voltage of the first battery module when the output voltage of the first battery module is greater than the output voltage of the first battery module and the second battery module, and wherein, when the first Adjusting the output voltage of the first battery module and the second battery module when the output voltage of the battery module and the second battery module is greater than the output voltage of the first battery module; The comparing device compares a reduced output voltage of the first battery module with a reduced output voltage of the first battery module and the second battery module. The battery management system of claim 14, wherein the adjusting device adjusts the output voltage sum of the first battery module and the second battery module. The battery management system of claim 14, wherein the reduced output voltage of the first battery module and the second battery module is approximately equal to the reduced output voltage of the first battery module. . The battery management system of claim 16, wherein the output voltage of each of the battery modules is approximately equal.