Equalization circuit and battery module

Abstract

The utility model relates to the technical field of circuits, in particular to an equalization circuit and a battery module. The equalization circuit comprises an equalization switch branch, a sampling branch and a driving sampling branch; the equalization switch branch comprises an equalization resistor RB and an equalization switch Q1 which are connected in series, one end of the equalization resistor RB is used for being connected with the positive electrode of the single battery, and the other end of the equalization resistor RB is used for being connected with the drain electrode D of the equalization switch Q1; the source electrode S of the equalization switch Q1 is used for being connected to the negative electrode of the single battery; the sampling branch comprises a first voltage acquisition end formed at one end of the equalization resistor RB and a second voltage acquisition end formed at a source electrode S of the equalization switch Q1; and the driving sampling branch comprises a first input end formed at one end of the balance resistor RB and a second input end formed at a grid electrode G of the balance switch Q1. The equalization circuit provided by the utility model realizes parallel operation of equalization and sampling, reduces current load, and effectively improves performance and stability of a battery management system.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of circuit, specifically, relate to equalizing circuit and battery module. BACKGROUND

[0002] In the battery management system, each single battery in the battery module may appear voltage difference in the charging and discharging process, if not timely adjust this unbalanced state, will lead to partial battery overcharge or overdischarge phenomenon, thereby seriously damaging the overall performance, service life and safety of the battery pack. Therefore, the equalizing circuit has been widely applied in the battery management system, its function is to dynamically adjust the voltage of each single battery, ensure that the battery pack can maintain the best working state.

[0003] However, in the prior art, the equalization loop and the sampling loop cannot operate in parallel, resulting in that the system cannot monitor the working state of the equalization loop in real time during the equalization process, and also cannot collect the voltage information of the single battery during the equalization process in time. In addition, in the existing design, the battery monitoring chip needs to bear a large current load, which not only reduces the durability and stability of the chip, but also may have adverse effects on the performance of the entire battery management system, thereby threatening the reliability and safety of the entire system. SUMMARY

[0004] The utility model relates to equalizing circuit and battery module, it can overcome certain or some defects of prior art.

[0005] Equalizing circuit, it includes equalizing switch branch, sampling branch and drive sampling branch, equalizing switch branch includes equalizing resistance RB and equalizing switch Q1 connected in series, one end of equalizing resistance RB is used for accessing the positive pole of single battery, the other end of equalizing resistance RB is used for accessing the drain D of equalizing switch Q1, the source S of equalizing switch Q1 is used for accessing the negative pole of single battery;

[0006] Sampling branch includes the first voltage collection end formed at one end of equalizing resistance RB and the second voltage collection end formed at the source S of equalizing switch Q1;

[0007] Drive sampling branch includes the first input end formed at one end of equalizing resistance RB and the second input end formed at the gate G of equalizing switch Q1.

[0008] The balancing circuit in the utility model, through the equalization switch branch sampling branch and the equalization circuit of driving sampling branch, realized the parallel operation of equalization loop and sampling loop.

[0009] As preferred, the equalization resistance RB includes a first resistance R1, a second resistance R2, a third resistance R3 and a fourth resistance R4 connected in parallel.

[0010] By including the first resistance R1, the second resistance R2, the third resistance R3 and the fourth resistance R4 connected in parallel, the equalization current can be adjusted more finely, thereby realizing more accurate equalization control of the single battery voltage.

[0011] As preferred, the one end of the equalization resistance RB is connected in series with a protection resistance R0 between the positive electrode of the required single battery.

[0012] By connecting the first protection resistance R0 in series between the equalization resistance RB and the positive electrode of the single battery, the protection resistance R0 plays a role of current limiting, which can limit the current size through the equalization circuit, preventing damage to the single battery or other parts of the equalization circuit due to excessive current in the equalization process.

[0013] As preferred, a capacitor C1 is connected in series between the first input end and the second input end.

[0014] By connecting the capacitor C1 in series between the first input end and the second input end, the high-frequency noise and interference in the control signal can be effectively removed, the driving circuit is protected from transient voltage impact, and the response speed and system stability of the equalization circuit are improved, thereby achieving the optimization of equalization effect, enhancing the reliability and safety of the battery management system.

[0015] As preferred, a capacitor C2 and a capacitor C3 are connected in series between the first voltage collection end and the second voltage collection end.

[0016] By connecting capacitors C2 and C3 in series between the first and second voltage acquisition terminals, high-frequency noise and low-frequency interference in the acquired voltage signal can be filtered out, improving the accuracy and stability of voltage acquisition. This ensures that the equalization circuit can more accurately monitor the voltage state of individual battery cells, optimize the equalization control strategy, improve the overall performance of the battery pack, and extend its service life.

[0017] Preferably, a filter resistor R5 is connected in series between one end of the equalization resistor RB and the first input terminal.

[0018] By connecting a filter resistor R5 in series between one end of the equalization resistor RB and the first input terminal, noise and interference in the control signal can be effectively filtered out, improving the purity and stability of the signal. This ensures that the equalization circuit can accurately receive and execute control commands, thereby optimizing the equalization process and improving the voltage equalization accuracy and overall performance of the battery pack.

[0019] Preferably, a filter resistor R6 is connected in series between one end of the equalization resistor RB and the first voltage acquisition terminal.

[0020] By connecting a filter resistor R6 in series between the equalization resistor RB and the first voltage acquisition terminal, the voltage signal transmitted from the equalization resistor RB to the first voltage acquisition terminal becomes smoother and more stable. This significantly improves the accuracy of voltage acquisition in the battery equalization circuit, enhances the circuit's anti-interference capability, protects subsequent circuits from damage, and optimizes circuit performance.

[0021] Preferably, a driving resistor R7 is connected in series between the gate G of the equalization switch Q1 and the second input terminal, and a current-limiting resistor R8 is connected in parallel between the driving resistor R7 and the second input terminal.

[0022] By connecting the driving resistor R7 in series between the gate G and the second input terminal of the equalization switch Q1, the driving current flowing to the gate G can be effectively controlled, ensuring that the equalization switch Q1 can be turned on or off stably and reliably. At the same time, the parallel current-limiting resistor R8 can provide additional current protection under transient conditions to prevent the gate G from being impacted by excessive current.

[0023] Preferably, Zener diodes D1 and D2 are connected in parallel between the gate G and source S of the equalization switch Q1.

[0024] By connecting Zener diodes D1 and D2 in parallel between the gate (G) and source (S) of the equalizing switch Q1, a more robust voltage protection mechanism can be formed. This design not only ensures that the gate voltage is stably limited within a safe range, preventing damage to the equalizing switch Q1 from excessively high or low voltage, but also enhances the redundancy and reliability of the circuit through the parallel connection of the two Zener diodes. Even if one Zener diode fails, the other can continue to operate, providing stable voltage protection for the gate.

[0025] Preferably, the battery module includes multiple individual cells and multiple equalization circuits corresponding to any one of the individual cells.

[0026] By configuring each individual cell in the battery module with multiple equalization loops employing any of the aforementioned equalization circuits, the voltage equalization capability of the battery module can be significantly improved. This design not only ensures precise and stable voltage equalization control for each individual cell but also enhances the safety and reliability of the entire battery module through the parallel operation of multiple equalization loops. Attached Figure Description

[0027] Figure 1 This is a circuit diagram of the equalization circuit in Example 1.

[0028] Figure 2 This is a schematic diagram of the structure of a battery module in Example 2. Detailed Implementation

[0029] To further understand the content of this utility model, a detailed description of the utility model is provided in conjunction with the embodiments. It should be understood that the embodiments are merely illustrative of the utility model and are not intended to limit it.

[0030] Example 1

[0031] like Figure 1 The equalization circuit shown in Embodiment 1 includes an equalization switch branch, a sampling branch, and a driving sampling branch. The equalization switch branch includes an equalization resistor RB and an equalization switch Q1 connected in series. One end of the equalization resistor RB is used to connect to the positive terminal of a single cell, and the other end of the equalization resistor RB is used to connect to the drain D of the equalization switch Q1. The source S of the equalization switch Q1 is used to connect to the negative terminal of a single cell.

[0032] The sampling branch includes a first voltage acquisition terminal formed at one end of the equalization resistor RB, and a second voltage acquisition terminal formed at the source S of the equalization switch Q1.

[0033] The driving sampling branch includes a first input terminal formed at one end of the equalizing resistor RB and a second input terminal formed at the gate G of the equalizing switch Q1.

[0034] In this embodiment, the equalization circuit is composed of an equalization switch branch, a sampling branch, and a driving sampling branch. The equalization switch branch realizes accurate regulation of the single battery voltage through the series connection of the equalization resistor RB and the equalization switch Q1. One end of the equalization resistor RB is connected to the positive electrode of the single battery, and the other end is connected to the drain D of the equalization switch Q1. The source S of the equalization switch Q1 is connected to the negative electrode of the single battery. When the equalization switch Q1 is turned on, the single battery can discharge through the equalization resistor RB, thereby achieving the purpose of equalizing the voltage.

[0035] The sampling branch collects the voltage at one end of the equalization resistor RB and the voltage at the source S of the equalization switch Q1 through the first voltage collection end and the second voltage collection end, respectively, providing accurate feedback signals for voltage equalization control. These collected voltage signals can be used to monitor the voltage state of the single battery in real time and serve as the basis for controlling the turn-on or turn-off of the equalization switch Q1.

[0036] The driving sampling branch receives control signals through the first input end and the second input end and drives the action of the equalization switch Q1. The first input end is connected to one end of the equalization resistor RB and receives control signals or sampling signals from the battery monitoring chip; the second input end is connected to the gate G of the equalization switch Q1 and is used to transmit the processed signals to the equalization switch Q1 to control its turn-on or turn-off. The source S of the equalization switch Q1 is connected to the ground GND, providing a stable reference potential for the entire equalization circuit.

[0037] According to the above description, the equalization circuit realizes rapid and stable equalization adjustment of the single battery voltage by accurately controlling the turn-on and turn-off of the equalization switch Q1. At the same time, the accurate voltage feedback signals provided by the sampling branch enable the equalization circuit to dynamically adjust according to the real-time voltage state of the single battery, thereby improving the overall performance and consistency of the battery module.

[0038] In this embodiment, the equalization resistor RB includes the first resistor R1, the second resistor R2, the third resistor R3, and the fourth resistor R4 connected in parallel.

[0039] Specifically, the equalization resistor RB connects the first resistor R1, the second resistor R2, the third resistor R3, and the fourth resistor R4 in parallel to achieve more precise and flexible equalization control of the single battery voltage. This design not only improves the accuracy and speed of voltage equalization but also enables adjustment of resistance values to optimize equalization effects according to actual needs. At the same time, the parallel connection of multiple resistors increases the redundancy of the circuit, improving the reliability and stability of the circuit. In addition, by reasonably selecting and matching resistance values, performance can be guaranteed while effectively controlling costs.

[0040] In this embodiment, the one end of the equalization resistor RB is connected in series with the protection resistor R0 between the positive electrode of the required access single battery.

[0041] Specifically, the protection resistor R0 arranged between the equalization resistor RB and the positive electrode of the single battery can limit the size of the discharge current, preventing safety problems such as circuit damage or fire caused by excessive current. By connecting the first protection resistor R0 in series, the current during the equalization process can be more stable, thereby improving the accuracy and stability of voltage equalization. This helps to reduce the voltage difference between single batteries and prolong the service life of the battery module.

[0042] In this embodiment, the first input end and the second input end are connected in series with the capacitor C1.

[0043] Specifically, the capacitor C1 is connected in series between the first input end and the second input end, both of which are connected to the battery monitoring chip. The first input end receives control signals or sampling signals from the battery monitoring chip for monitoring the voltage state of the single battery. The second input end is usually connected to the control end (gate G) of the equalization switch Q1 for transmitting the processed signal to the equalization switch Q1 to control its conduction or shutdown. Through the capacitor C1, the noise and fluctuations in the control signal can be effectively removed, improving the stability and accuracy of the signal, which helps the battery monitoring chip to more accurately determine the voltage state of the single battery, thereby generating more accurate control signals. At the same time, through the capacitor C1, its charge absorption and release characteristics effectively enhance the anti-interference ability of the circuit, protecting the battery monitoring chip and the equalization circuit from damage caused by external factors such as electromagnetic interference. Moreover, through this direct series design, the circuit design is simplified, and additional filtering or decoupling elements are reduced, thereby reducing the cost of the circuit and improving the production efficiency.

[0044] In this embodiment, the first voltage collection end and the second voltage collection end are connected in series with the capacitor C2 and the capacitor C3.

[0045] Specifically, the capacitor C2 and the capacitor C3 are connected in series between the first voltage collection end and the second voltage collection end. Through the series connection of the capacitor C1 and the capacitor C2, the voltage signal is filtered and stabilized, effectively removing high-frequency noise and interference in the signal, thereby improving the accuracy and stability of voltage collection.

[0046] In this embodiment, the one end of the equalization resistor RB is connected in series with the first input end and the filter resistor R5.

[0047] Specifically, by connecting the filter resistor R5 in series between the one end of the equalization resistor RB and the first input end, the voltage signal is preprocessed and filtered, effectively improving the signal quality and circuit stability, and protecting the subsequent circuit from damage caused by excessive current.

[0048] In this embodiment, a filter resistor R6 is connected in series between one end of the equalization resistor RB and the first voltage acquisition terminal.

[0049] Specifically, a filter resistor R6 is connected in series between one end of the equalization resistor RB and the first voltage acquisition terminal. The addition of the filter resistor R6 makes the voltage signal smoother and more stable, improving the monitoring accuracy of the battery cell voltage. At the same time, it filters out high-frequency noise and interference in the signal, significantly improving the accuracy and stability of voltage acquisition.

[0050] In this embodiment, the gate G of the equalization switch Q1 is connected in series with the second input terminal by a driving resistor R7, and the driving resistor R7 is connected in parallel with a current limiting resistor R8.

[0051] Specifically, the drive resistor R7 is connected in series between the gate G of the equalizer Q1 and the second input terminal to provide the necessary drive current to the gate. By adjusting the resistance value of R7, the magnitude of the gate current can be controlled, thereby affecting the switching speed and power consumption of the equalizer Q1. The current-limiting resistor R8 is connected in parallel across the drive resistor R7 to limit the maximum value of the gate current. In certain situations, such as when the gate voltage is too high or a short circuit occurs in the gate circuit, R8 can prevent excessive current from flowing through the gate, thus protecting the equalizer Q1 from damage. The selection of the resistance value of R8 needs to comprehensively consider the characteristics of the gate circuit and the withstand capability of the equalizer Q1.

[0052] In this embodiment, Zener diodes D1 and D2 are connected in parallel between the gate G and source S of the equalization switch Q1.

[0053] Specifically, to enhance the protection of the MOSFET, we have adopted dual protection measures. Among them,

[0054] The Zener diode D2 is an additional protection diode added between the gate (G) and source (S) of the MOSFET Q1, which incorporates a transient voltage suppressor (TVS). The TVS provides a nanosecond-level response and suppresses transient overvoltages between the gate and source, protecting the MOSFET from damage, extending its lifespan, and improving circuit reliability. The Zener diode D1 conducts when the voltage exceeds its Zener voltage, discharging excess voltage and providing further protection for the MOSFET. Together, these two diodes ensure comprehensive protection of the MOSFET against transient overvoltages, enhancing the overall stability of the circuit.

[0055] Example 2

[0056] like Figure 2 The schematic diagram of a battery module in this embodiment 2 shows that it includes multiple individual cells and multiple equalization circuits corresponding to any one of the individual cells. The equalization circuits adopt any of the equalization circuits described in embodiment 1.

[0057] Specifically, the battery module is composed of multiple single batteries (such as Cell_1, Cell_2, etc.), which are connected in series or parallel to provide the required voltage and current. Each single battery is equipped with a corresponding balancing circuit, which monitors and adjusts the voltage of the single battery to ensure voltage balance within the battery module. The balancing circuit achieves rapid and stable balancing adjustment of the single battery voltage by precisely controlling the on and off of the balancing switch Q1. Meanwhile, the accurate voltage feedback signal provided by the sampling branch allows the balancing circuit to accurately adjust the voltage of the single battery based on real-time voltage information provided by the battery monitoring chip. This not only improves the voltage consistency between each single battery in the battery module, but also prolongs the service life of the battery module. Through precise voltage balancing control, the battery module can maintain higher efficiency and safety during charging and discharging.

[0058] It is easy to understand that those skilled in the art can combine, split, recombine, etc. the embodiments of the present application on the basis of one or several embodiments provided by the present application to obtain other embodiments, and these embodiments do not exceed the protection scope of the present application.

[0059] The above describes the present application and its embodiments in a schematic manner, which is not restrictive, and the embodiments shown are only part of the embodiments of the present application, and the actual structure is not limited thereto. Therefore, if a person skilled in the art is inspired by this, without departing from the spirit of the present application, without creative design, similar structure and embodiments of the technical solution can be obtained, which should belong to the protection scope of the present application.

Claims

1. An equalization circuit, characterized by, The equalization switch branch, the sampling branch and the driving sampling branch are included; the equalization switch branch includes the equalization resistor RB and the equalization switch Q1 connected in series, one end of the equalization resistor RB is used for accessing the positive pole of the single battery, and the other end of the equalization resistor RB is used for accessing the drain D of the equalization switch Q1; the source S of the equalization switch Q1 is used for accessing the negative pole of the single battery; The sampling branch includes the first voltage collection end formed at the one end of the equalization resistor RB and the second voltage collection end formed at the source S of the equalization switch Q1; The driving sampling branch includes the first input end formed at the one end of the equalization resistor RB and the second input end formed at the gate G of the equalization switch Q1.

2. The equalization circuit of claim 1, wherein, The equalization resistor RB includes the first resistor R1, the second resistor R2, the third resistor R3 and the fourth resistor R4 connected in parallel.

3. The equalization circuit of claim 1, wherein, The one end of the equalization resistor RB is connected in series with the protection resistor R0 required to access the positive pole of the single battery.

4. The equalization circuit of claim 1, wherein, The first input end and the second input end are connected in series with the capacitor C1.

5. The equalization circuit of claim 1, wherein, The first voltage collection end and the second voltage collection end are connected in series with the capacitor C2 and the capacitor C3.

6. The equalization circuit of claim 1, wherein, The one end of the equalization resistor RB and the first input end are connected in series with the filter resistor R5.

7. The equalization circuit of claim 6, wherein, The one end of the equalization resistor RB and the first voltage collection end are connected in series with the filter resistor R6.

8. The equalization circuit of claim 7, wherein, The gate G of the equalization switch Q1 and the second input end are connected in series with the driving resistor R7, and the driving resistor R7 is connected in parallel with the current-limiting resistor R8.

9. The equalization circuit of claim 8, wherein, The gate G of the equalization switch Q1 and the source S are connected in parallel with the voltage stabilizing diode D1 and the voltage stabilizing diode D2.

10. A battery module, characterized by: The equalization circuit adopts any one of the equalization circuits in claims 1-9.

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