CN220934884U - Equalization circuit and energy storage device - Google Patents

Abstract

The utility model discloses an equalization circuit and energy storage equipment. The equalization circuit is used for equalizing the voltage of the battery cell and comprises a control module, a first switch module, a second switch module, at least two equalization resistors and an equalization bus; the control module determines the battery cells needing to be balanced according to the voltage difference of the battery cells, and sends a first balanced control signal to the first switch module and a second balanced control signal to the second switch module when the voltage difference of the battery cells is larger than a first set threshold value; the first switch module controls the equalization resistor to be connected to two ends of the corresponding battery cell to be equalized according to the first equalization control signal; the second switch module controls the equalization resistor corresponding to the cell to be equalized of the maximum voltage to be connected to the equalization bus according to the second equalization control signal, and controls the equalization resistor corresponding to the at least one cell not to be equalized to be connected to the equalization bus. The energy storage device equalization circuit has the advantages of being fast in equalization and high in efficiency.

Description

Equalization circuit and energy storage device

Technical Field

The present utility model relates to the field of electronic circuits, and in particular, to an equalization circuit and an energy storage device.

Background

The energy storage device is used for storing electric energy, can supply power for external equipment, and the inside of the energy storage device comprises a plurality of single battery cores, and the equalization circuit is a circuit for equalizing all single battery cores in the energy storage device, so that the overall performance of the energy storage device can be improved.

The portable energy storage equipment in the current market basically uses a passive equalization circuit due to the size and power, but the capacity of the battery core of the current portable energy storage equipment is greatly increased due to the fact that the capacity of the current portable energy storage equipment is larger and larger, so that the phenomenon that the equalization power of the current passive equalization circuit is not matched is caused, and the equalization efficiency is lower.

Disclosure of utility model

The utility model provides an equalizing circuit and energy storage equipment, which are used for solving the problem of low equalizing efficiency of the equalizing circuit in the prior art.

According to an aspect of the present utility model, there is provided an equalizing circuit for equalizing voltages of cells, comprising: the control module, the first switch module, the second switch module, at least two equalizing resistors and an equalizing bus;

The control module is used for determining the battery cell to be balanced as a battery cell to be balanced according to the voltage difference of the battery cell, sending a first balance control signal to the first switch module and sending a second balance control signal to the second switch module when the voltage difference of the battery cell is larger than a first set threshold value;

The first switch module is connected with the control module, the equalization resistors and the battery cells, the equalization resistors are in one-to-one correspondence with the battery cells, and the first switch module is used for controlling the equalization resistors to be connected to two ends of the corresponding battery cells to be equalized according to the first equalization control signals;

The balancing bus is connected with the second switch module, the second switch module is connected with the control module and the balancing resistor, and the second switch module is used for controlling the balancing resistor corresponding to the cell to be balanced of the maximum voltage to be connected to the balancing bus according to the second balancing control signal and controlling the balancing resistor corresponding to at least one cell not to be balanced to be connected to the balancing bus.

Optionally, the voltage difference of the battery cell includes a difference in voltage of the battery cell or a difference in rate of change of the voltage of the battery cell.

Optionally, the first switch module includes at least two first switches, the first end of first switch is connected the first end of balancing resistance, the second end of first switch is connected the positive pole of electric core, the third end of first switch is connected the second end of balancing resistance, the fourth end of first switch is connected the negative pole of electric core, the control end of first switch is connected the control module.

Optionally, the second switch module includes two at least second switches, the balanced busbar includes first busbar and second busbar, first end connection of second switch the first busbar, the second end connection of second switch the first end of balanced resistance, the third end connection of second switch the second busbar, the fourth end connection of second switch the second end of balanced resistance, the control end connection of second switch the control module.

Optionally, the equalization circuit further includes a first sampling module, where the first sampling module is connected to the positive electrode, the negative electrode and the control module of the battery cell, and the first sampling module is configured to collect the voltage of the battery cell and transmit the voltage of the battery cell to the control module.

Optionally, the control module is configured to determine, according to the voltage difference of the electrical core, the electrical core to be balanced as the electrical core to be balanced, send a third equalization control signal to the first switch module and send a fourth equalization control signal to the second switch module when the voltage difference of the electrical core is greater than a second set threshold; the first switch module is used for controlling the equalization resistor to be connected to two ends of the corresponding battery cell to be equalized according to the third equalization control signal, and the second switch module is used for controlling the equalization resistor to be disconnected from the equalization bus according to the fourth equalization control signal; the first set threshold is greater than the second set threshold.

Optionally, the control module includes a signal processing unit and a switch control unit, the signal processing unit is connected with the first sampling module and the switch control unit, the switch control unit is connected with the first switch module and the second switch module, the signal processing unit is used for outputting a control signal after processing and analyzing a voltage signal output by the first sampling module, and the switch control unit is used for outputting a switch control signal according to the control signal so as to control the first switch module and the second switch module to act.

Optionally, the switch control unit further includes a detection subunit, where the detection subunit is connected to the first switch module, the second switch module, and the signal processing unit, and the detection subunit is configured to feed back action durations of the first switch module and the second switch module to the signal processing unit.

Optionally, the equalization circuit further includes a second sampling module, the second sampling module is connected to the first bus, the second bus and the control module, the second sampling module is configured to collect voltages of the first bus and the second bus, and the control module is further configured to control the first switch module and the second switch module according to a voltage signal output by the second sampling module.

According to another aspect of the utility model, there is provided an energy storage device comprising the equalization circuit.

The technical scheme of the embodiment of the utility model provides an equalizing circuit which comprises a control module, a first switch module, a second switch module, at least two equalizing resistors and an equalizing bus; the control module determines the battery cells needing to be balanced according to the voltage difference of the battery cells, and sends a first balanced control signal to the first switch module and a second balanced control signal to the second switch module when the voltage difference of the battery cells is larger than a first set threshold value; the first switch module controls the equalization resistor to be connected to two ends of the corresponding battery cell to be equalized according to the first equalization control signal; the second switch module controls the equalization resistor corresponding to the cell to be equalized of the maximum voltage to be connected to the equalization bus according to the second equalization control signal, and controls the equalization resistor corresponding to at least one cell not to be equalized to be connected to the equalization bus, namely, the equalization resistors corresponding to the cells not to be equalized are connected in parallel with the equalization resistor corresponding to the cell to be equalized through the bus, so that the cell to be equalized can be rapidly discharged through the parallel resistors, rapid equalization is realized, the advantages of high equalization efficiency are achieved, meanwhile, the parallel resistors are connected to the anode and the cathode of the cell to be equalized, the discharge current of the cell to be equalized is increased, and the method is applicable to equalization of the cell with larger capacity. The problem of equalization circuit equalization efficiency is lower among the prior art is solved.

It should be understood that the description in this section is not intended to identify key or critical features of the embodiments of the utility model or to delineate the scope of the utility model. Other features of the present utility model will become apparent from the description that follows.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings required for the description of the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present utility model, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of an equalization circuit according to an embodiment of the present utility model;

fig. 2 is a circuit diagram of an equalization circuit according to an embodiment of the present utility model;

fig. 3 is a circuit diagram of another equalizing circuit according to an embodiment of the present utility model;

fig. 4 is a flowchart of an equalization method of an energy storage device according to an embodiment of the present utility model.

Detailed Description

In order that those skilled in the art will better understand the present utility model, a technical solution in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present utility model, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present utility model without making any inventive effort, shall fall within the scope of the present utility model.

It should be noted that the terms "first," "second," and the like in the description and the claims of the present utility model and the above figures are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used may be interchanged where appropriate such that the embodiments of the utility model described herein may be implemented in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The portable energy storage equipment in the current market basically uses a passive equalization circuit due to the size and power, but the capacity of the current portable energy storage equipment is increased to 1000-3000Wh, and the capacity of a battery core is also greatly increased, so that the current passive equalization circuit has the phenomenon that the equalization power is not matched more and more, and the uniformity of the battery core is reduced after the equalization is impossible for a long time, thereby reducing the service life and the performance of the equipment. The passive equalization capability of the conventional portable energy storage equipment is basically 50mA-80mA due to the product size and cost requirements, and the efficiency is too low compared with the current single-string battery cell with the parallel battery cell capacity of about 50 Ah.

In order to solve the above-mentioned problems, an equalization circuit is provided in an embodiment of the present utility model, and fig. 1 is a schematic structural diagram of the equalization circuit provided in the embodiment of the present utility model, where, as shown in fig. 1, an energy storage device C includes at least two electrical cores, and the equalization circuit includes a control module 110, a first switch module 120, a second switch module 130, at least two equalization resistors Rj, and an equalization bus, where the equalization bus includes a first bus L1 and a second bus L2; the control module 110 is configured to determine, according to the voltage difference of the battery cells, the battery cells to be balanced as the battery cells to be balanced, send a first equalization control signal to the first switch module 120 and send a second equalization control signal to the second switch module 130 when the voltage difference of the battery cells is greater than a first set threshold; the first switch module 120 is connected with the control module 110, the equalization resistors Rj and the battery cells, the equalization resistors Rj are in one-to-one correspondence with the battery cells, and the first switch module 120 is used for controlling the equalization resistors Rj to be connected to two ends of the corresponding battery cells to be equalized according to a first equalization control signal; the first bus L1 and the second bus L2 are connected with the second switch module 130, the second switch module 130 is connected with the control module 110 and the equalization resistor Rj, the second switch module 130 is used for controlling the first end and the second end of the equalization resistor Rj corresponding to the cell to be equalized of the maximum voltage according to the second equalization control signal to be connected with the first bus L1 and the second bus L2 respectively, and controlling the first end and the second end of the equalization resistor Rj corresponding to the at least one cell not to be equalized to be connected with the first bus L1 and the second bus L2 respectively.

In this embodiment, the energy storage device C is a device for storing electric energy, for example, includes a storage battery, etc., the storage battery includes a plurality of electric cores inside, and the equalization circuit is used for equalizing the plurality of electric cores inside the energy storage device C, so that the charging and discharging of the plurality of electric cores are balanced, the consistency of the electric cores is improved, and the equalization circuit has an important role in prolonging the service life of the energy storage device C. The control module 110 is a module for performing data transmission and data processing. The first switch module 120 is a module for switching on or off the equalization resistor and the corresponding battery cell, the first switch module 120 includes at least two first switches, and the first switches are respectively in one-to-one correspondence with the equalization resistor Rj and the battery cell. The second switch module 130 is a module for switching on or off the equalizing resistor with the first bus L1 and the second bus L2, and the second switch module 130 includes at least two second switches, and the second switches are respectively in one-to-one correspondence with the equalizing resistor Rj and the battery cell. The equalization resistor Rj is used for equalizing the battery cells to be equalized, the first bus L1 and the second bus L2 are two wires, and when the equalization resistors Rj are connected to the first bus L1 and the second bus L2, the equalization resistors Rj are connected in parallel. The voltage difference of the battery cells comprises a difference of the voltage of the battery cells or a difference of the change rate of the voltage of the battery cells. For example, the difference of each cell may be small in the early stage of the life cycle of the energy storage device, the voltage difference of the cells may be represented by the difference of the voltages of the cells, and the voltage difference of the cells may be represented by the difference of the voltage change rates of the cells in the charge and discharge process of the energy storage device.

For example, when the control module 110 detects that the difference between the voltages of n cells in the energy storage device and the voltages of the remaining cells is greater than the first set threshold, the control module 110 determines that the n cells are cells to be balanced, and uses the n cells as the cells to be balanced. The control module 110 sends a first equalization control signal to the first switch module 120 and sends a second equalization control signal to the second switch module 130, and the first switch module 120 enables the first switches corresponding to the n electric cores to be closed according to the first equalization signal so as to control the corresponding equalization resistors Rj to be connected in parallel at two ends of the corresponding electric cores to be equalized, and the n electric cores to be equalized realize electric core equalization through discharging. The second switch module 130 controls the second switch corresponding to the maximum voltage cell to be balanced in the n cells to be balanced to be closed according to the second balanced control signal, so that the first end and the second end of the balancing resistor Rj corresponding to the maximum voltage cell to be balanced are respectively connected to the first bus L1 and the second bus L2, the second switch module 120 simultaneously controls the second switch corresponding to the at least one non-balanced cell to be closed, so that the first end and the second end of the balancing resistor Rj corresponding to the at least one non-balanced cell are respectively connected to the first bus L1 and the second bus L2, and the balancing resistors Rj corresponding to the multiple non-balanced cells are connected in parallel and then connected in parallel with the balancing resistor Rj corresponding to the balanced cell to be balanced, so that the discharge current of the maximum voltage cell to be balanced is increased, the discharge speed is increased, and the balancing efficiency of the energy storage device is improved.

The technical scheme of the embodiment provides an equalizing circuit which comprises a control module, a first switch module, a second switch module, at least two equalizing resistors and an equalizing bus; the control module determines the battery cells needing to be balanced according to the voltage difference of the battery cells, and sends a first balanced control signal to the first switch module and a second balanced control signal to the second switch module when the voltage difference of the battery cells is larger than a first set threshold value; the first switch module controls the equalization resistor to be connected to two ends of the corresponding battery cell to be equalized according to the first equalization control signal; the second switch module controls the equalization resistor corresponding to the cell to be equalized of the maximum voltage to be connected to the equalization bus according to the second equalization control signal, and controls the equalization resistor corresponding to at least one cell not to be equalized to be connected to the equalization bus, namely, the equalization resistors corresponding to the cells not to be equalized are connected in parallel with the equalization resistor corresponding to the cell to be equalized through the bus, so that the cell to be equalized can be rapidly discharged through the parallel resistors, rapid equalization is realized, the advantages of high equalization efficiency are achieved, meanwhile, the parallel resistors are connected to the anode and the cathode of the cell to be equalized, the discharge current of the cell to be equalized is increased, and the method is applicable to equalization of the cell with larger capacity. The problem of equalization circuit equalization efficiency is lower among the prior art is solved.

Fig. 2 is a circuit diagram of an equalization circuit according to an embodiment of the present utility model, as shown in fig. 2, the first switch module 120 includes at least two first switches, a first end of each first switch is connected to a first end of the equalization resistor Rj, a second end of each first switch is connected to an anode of the battery cell, a third end of each first switch is connected to a second end of the equalization resistor Rj, a fourth end of each first switch is connected to a cathode of the battery cell, and a control end of each first switch is connected to the control module 110.

In this embodiment, the first switches are respectively in one-to-one correspondence with the equalization resistors Rj and the battery cells, and referring to the above embodiment, when the first switch module 120 controls the equalization resistors Rj to be connected to two ends of the corresponding battery cell to be equalized according to the first equalization control signal, the first switch corresponding to the battery cell to be equalized in the first switch module 120 is closed, the first end of the equalization resistor Rj is connected to the positive electrode of the battery cell to be equalized, the second end of the equalization resistor Rj is connected to the negative electrode of the battery cell to be equalized, and the battery cell to be equalized discharges through the connection of the equalization resistor Rj corresponding to the first switch module. Wherein the first switch comprises a first double pole double throw relay switch K.

With continued reference to fig. 2, the second switch module 130 includes at least two second switches, a first end of each second switch is connected to the first bus L1, a second end of each second switch is connected to the first end of the equalizing resistor Rj, a third end of each second switch is connected to the second bus L2, a fourth end of each second switch is connected to the second end of the equalizing resistor Rj, and a control end of each second switch is connected to the control module 110.

In this embodiment, the second switches are respectively corresponding to the equalization resistors Rj and the battery cells one by one, referring to the above embodiment, when the second switch module 130 controls the first ends and the second ends of the equalization resistors Rj corresponding to the battery cells to be equalized with the maximum voltage according to the second equalization control signal to be connected to the first bus L1 and the second bus L2 respectively, and controls the first ends and the second ends of the equalization resistors Rj corresponding to the battery cells not to be equalized to be connected to the first bus L1 and the second bus L2 respectively, the second switch corresponding to the battery cells to be equalized with the maximum voltage in the second switch module 130 is closed, and meanwhile, the second switch corresponding to the battery cells not to be equalized is closed, at this time, the first ends and the second ends of the equalization resistors Rj corresponding to the battery cells to be equalized with the maximum voltage are respectively connected to the first bus L1 and the second bus L2, so that the two ends of the battery cells to be equalized, to which the equalization resistors Rj are connected in parallel, are connected, are realized, and the discharging speed of the battery cells to be equalized with the maximum voltage is improved. Wherein the second switch comprises a second double pole double throw relay switch KS.

Fig. 3 is a circuit diagram of another equalizing circuit according to an embodiment of the present utility model, and as shown in fig. 3, the equalizing circuit further includes a first sampling module 310, where the first sampling module 310 is connected to the positive electrode and the negative electrode of the battery cell and the control module 110, and the first sampling module 310 is configured to collect the voltage of the battery cell and transmit the voltage of the battery cell to the control module 110.

In this embodiment, the first sampling module 310 collects the voltages of each battery cell in the energy storage device, and transmits the collected voltages to the control module 110, and the control module 110 processes the collected voltages to obtain the voltage difference of the battery cells. For example, when the control module 110 obtains that the voltage difference of the battery cell is greater than the first set threshold according to the voltage output by the first sampling module 310, the control module 110 sends a first equalization control signal to the first switch module 120 and sends a second equalization control signal to the second switch module 130, and the first switch module 120 and the second switch module 130 implement equalization on the energy storage device by controlling the corresponding first switch and second switch to be closed or opened.

With continued reference to fig. 3, the control module 110 includes a signal processing unit and a switch control unit, the signal processing unit is connected to the first sampling module 310 and the switch control unit, the switch control unit is connected to the first switch module 120 and the second switch module 130, the signal processing unit is configured to output a control signal after processing and analyzing a voltage signal output by the first sampling module 310, and the switch control unit is configured to output a switch control signal according to the control signal, so as to control the first switch module 120 and the second switch module 130 to act.

In this embodiment, the signal processing unit is a unit that processes signals, for example, the signal processing unit may be a microcontroller, and the switch control unit is a unit that controls the first switch module 120 and the second switch module 130. The signal processing unit receives the voltage signal output by the first sampling module 310, and outputs a control signal after processing the voltage signal. For example, when the signal processing unit processes the voltage signal output by the first sampling module 310 to obtain that the voltage difference between the battery cells is smaller, the control signal output by the signal processing unit is a low-level signal, the switch control signal output by the switch control unit is a low-level signal, and the first switch module 120 and the second switch module 130 are kept in initial states, at this time, the battery cells in the energy storage device do not need to be balanced. When the signal processing unit detects that the voltage difference of each battery cell is greater than the first set threshold, the control signal output by the signal processing unit is a high-level signal, the switch control signal output by the switch control unit is a first equalization control signal and a second equalization control signal respectively, and the first switch module 120 and the second switch module 130 control the corresponding first switch and the second switch to be closed or opened according to the first equalization control signal and the second equalization control signal respectively, so that the equalization of the energy storage device is realized.

On the basis of the above embodiment, the control module 110 is configured to determine, according to the voltage difference of the battery cells, the battery cells to be balanced as the battery cells to be balanced, and send a third equalization control signal to the first switch module 120 and send a fourth equalization control signal to the second switch module 130 when the voltage difference of the battery cells is greater than the second set threshold; the first switch module 120 is configured to control the equalization resistor Rj to be connected to two ends of the corresponding cell to be equalized according to the third equalization control signal, and the second switch module 130 is configured to control the first end and the second end of the equalization resistor Rj to be disconnected from the first bus L1 and the second bus L2 respectively according to the fourth equalization control signal; wherein the first set threshold is greater than the second set threshold.

For example, in the early stage of the life cycle of the energy storage battery pack, the consistency of each battery cell in the energy storage device is better, the difference is not great, when the control module 110 receives the voltage signal output by the first sampling module 310 to obtain that the voltage difference of the battery cell is greater than the second set threshold, it determines that the battery cell to be balanced, the control module 110 sends a third balanced control signal to the first switch module 120, and sends a fourth balanced control signal to the second switch module 130, the first switch module 120 controls the balanced resistor Rj to be connected to two ends of the corresponding battery cell to be balanced according to the third balanced control signal, and the second switch module 130 controls the first ends and the second ends of all the balanced resistors Rj to be disconnected from the first bus L1 and the second bus L2 respectively according to the fourth balanced control signal. By connecting the equalization resistor with the corresponding battery cell to be equalized, flexible equalization control of the energy storage equipment is realized. When the voltage difference of an internal battery cell is larger and larger along with longer use time in an application process of the energy storage device, the voltage of a certain battery cell may be increased rapidly in a virtual manner during charging, and according to the embodiment, when the voltage difference of the battery cell is larger than a first set threshold value, the control module 110 outputs a first balanced control signal and a second balanced control signal, the first switch module 120 controls the balanced resistor Rj to be connected to two ends of the corresponding battery cell to be balanced according to the first balanced control signal, the second switch module 130 controls the first ends and the second ends of a plurality of balanced resistors Rj including the balanced resistor Rj corresponding to the battery cell to be balanced which is excessively fast in voltage increase to be connected to the first bus L1 and the second bus L2 respectively, so that the discharge speed of the battery cell to be balanced of the maximum voltage is improved, and high power and high efficiency of the battery cell are realized.

On the basis of the above embodiment, the switch control unit further includes a detection subunit, where the detection subunit is connected to the first switch module 120, the second switch module 130, and the signal processing unit, and the detection subunit is configured to feed back the action durations of the first switch module 120 and the second switch module 130 to the signal processing unit.

In the present embodiment, the detection subunit is a unit that detects the first switch in the first switch module 120 and the second switch in the second switch module 130. For example, when the voltage difference of the battery cells is greater than the second set threshold, the first switch module 120 controls the first switch corresponding to the battery cell to be balanced to be closed according to the third balancing control signal, the corresponding balancing resistor Rj is connected to two ends of the battery cell to be balanced corresponding to the first switch, the detecting subunit detects the closing time of the first switch, for example, when the closing time of the first switch reaches 30S, the detecting subunit feeds back the closing time of the first switch to the signal processing unit, the signal processing unit outputs the control signal as a low level signal, the switch control module outputs the low level signal, the first switch in the first switch module is opened, the energy storage device is in an unbalanced state, the first sampling module 310 resamples each battery cell, and the control module 110 reconfirms the battery cell to be balanced according to the sampling voltage, so that quick, flexible and efficient balancing can be realized.

With continued reference to fig. 3, the equalizing circuit further includes a second sampling module 320, where the second sampling module 320 is connected to the first bus L1, the second bus L2, and the control module 110, and the second sampling module 320 is configured to collect voltages of the first bus L1 and the second bus L2, and the control module 110 is further configured to control the first switch module 120 and the second switch module 130 according to a voltage signal output by the second sampling module 320.

In this embodiment, the second sampling module 320 is a module for collecting voltages on the first bus L1 and the second bus L2, where the control module 110 obtains that the voltage difference of the battery cell is greater than the first set threshold or the second set threshold according to the voltage signal output by the first collecting module 310, so as to determine whether the first bus L1 and the second bus L2 need to be normally judged before the battery cell is to be balanced, that is, whether the voltage exists on the first bus L1 and the second bus L2 is judged according to the voltage signal output by the second sampling module 320, if the voltage of the first bus L1 and the voltage of the second bus L2 are both 0, the first bus L1 and the second bus L2 are normal, and when at least one bus has a voltage, the first equalization control signal, the second equalization control signal, the third equalization control signal or the fourth equalization control signal are not output any more, so that the battery cell and the circuit cannot be burned out due to the abnormality of the equalization circuit is ensured.

On the basis of the embodiment, the embodiment of the utility model also provides an equalization method of the energy storage device, which is executed by the equalization circuit. Fig. 4 is a flowchart of an equalization method of an energy storage device according to an embodiment of the present utility model, as shown in fig. 4, after the energy storage device starts charging, a control module determines whether the energy storage device reaches a condition to be equalized (i.e., determines whether a voltage difference of a power cell is greater than a second set threshold) by receiving a voltage signal output by a first sampling module, when the condition to be equalized is not satisfied, the energy storage device continues charging, when the condition to be equalized is satisfied, the control module determines whether a voltage of a certain power cell rises rapidly (i.e., determines whether the voltage difference of the certain power cell is greater than the first set threshold), when the voltage of the certain power cell rises rapidly, the control module controls a switch corresponding to the power cell which does not need to be equalized to be closed, controls a switch corresponding to the power cell to be detected to be closed, other power cells to be equalized are balanced normally, and when the equalization time reaches 30 seconds, determines whether the voltage of the certain power cell rises rapidly again. When the voltage difference of the battery cells is greater than the second set threshold, the first switch module controls the equalization resistor Rj to be connected to two ends of the corresponding battery cells to be equalized according to the third equalization control signal, and the second switch module 130 controls the first end and the second end of the equalization resistor Rj to be disconnected from the first bus L1 and the second bus L2 respectively according to the fourth equalization control signal, that is, during normal equalization, the switches corresponding to the battery cells to be equalized are all disconnected. Wherein the switch in fig. 4 corresponds to the second double pole double throw relay switch KS in fig. 3. When the voltage of a certain cell does not rise rapidly, the equalization circuit starts normal equalization, and when the equalization time reaches 30 seconds, whether the voltage of the certain cell rises rapidly is judged again.

The embodiment of the utility model also provides energy storage equipment which comprises the equalization circuit. The energy storage device is used for storing electric energy, and comprises a storage battery and the like, wherein the storage battery comprises a plurality of electric cores, the equalization circuit is used for equalizing the electric cores in the energy storage device, so that the electric cores are balanced in charge and discharge, the consistency of the electric cores is improved, and the energy storage device has an important effect on prolonging the service life of the energy storage device.

In this embodiment, the control module may determine whether the voltage difference of the battery cells is greater than a first set threshold by analyzing the voltage signal output by the first sampling module, when the voltage difference of the battery cells is not greater than the first set threshold, each battery cell in the energy storage device does not need to be balanced, and when the voltage difference of the battery cells is greater than the first set threshold, the control module sends a first balanced control signal to the first switch module and sends a second balanced control signal to the second switch module, the first switch module controls the balanced resistor to be connected to two ends of the corresponding battery cell to be balanced according to the first balanced control signal, the second switch module controls the balanced resistor corresponding to the maximum voltage battery cell to be balanced according to the second balanced control signal to be connected to the first bus and the second bus, and controls the balanced resistor corresponding to at least one unbalanced battery cell to be connected to the first bus and the second bus, that is, the balanced resistors corresponding to the plurality of unbalanced battery cells are connected in parallel with the balanced resistor corresponding to the battery cell to be balanced through the bus, so that the balanced battery cell to be balanced is fast through the plurality of parallel resistors, and the balanced cell to realize high efficiency. The equalization circuit is applied to the energy storage equipment, so that the performance of the energy storage equipment can be improved, and the service life of the energy storage equipment can be prolonged.

It should be appreciated that various forms of the flows shown above may be used to reorder, add, or delete steps. For example, the steps described in the present utility model may be performed in parallel, sequentially, or in a different order, so long as the desired results of the technical solution of the present utility model are achieved, and the present utility model is not limited herein.

The above embodiments do not limit the scope of the present utility model. It will be apparent to those skilled in the art that various modifications, combinations, sub-combinations and alternatives are possible, depending on design requirements and other factors. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included in the scope of the present utility model.

Claims (10)

1. An equalization circuit for equalizing the voltage of a cell, comprising: the control module, the first switch module, the second switch module, at least two equalizing resistors and an equalizing bus;

The control module is used for determining the battery cell to be balanced as a battery cell to be balanced according to the voltage difference of the battery cell, sending a first balance control signal to the first switch module and sending a second balance control signal to the second switch module when the voltage difference of the battery cell is larger than a first set threshold value;

The first switch module is connected with the control module, the equalization resistors and the battery cells, the equalization resistors are in one-to-one correspondence with the battery cells, and the first switch module is used for controlling the equalization resistors to be connected to two ends of the corresponding battery cells to be equalized according to the first equalization control signals;

The balancing bus is connected with the second switch module, the second switch module is connected with the control module and the balancing resistor, and the second switch module is used for controlling the balancing resistor corresponding to the cell to be balanced of the maximum voltage to be connected to the balancing bus according to the second balancing control signal and controlling the balancing resistor corresponding to at least one cell not to be balanced to be connected to the balancing bus.

2. The equalization circuit of claim 1, wherein the voltage differential of the cells comprises a difference in the cell voltages or a difference in the cell voltage rate of change.

3. The equalization circuit of claim 1, wherein the first switch module comprises at least two first switches, a first end of the first switches being connected to a first end of the equalization resistor, a second end of the first switches being connected to a positive electrode of the cell, a third end of the first switches being connected to a second end of the equalization resistor, a fourth end of the first switches being connected to a cathode of the cell, and a control end of the first switches being connected to the control module.

4. The equalization circuit of claim 1, wherein the second switch module comprises at least two second switches, the equalization busbar comprises a first busbar and a second busbar, a first end of the second switch is connected to the first busbar, a second end of the second switch is connected to the first end of the equalization resistor, a third end of the second switch is connected to the second busbar, a fourth end of the second switch is connected to the second end of the equalization resistor, and a control end of the second switch is connected to the control module.

5. The equalization circuit of claim 1, further comprising a first sampling module connecting the positive pole, the negative pole, and the control module of the cell, the first sampling module configured to collect a voltage of the cell and transmit the cell voltage to the control module.

6. The equalization circuit of claim 1, wherein the control module is configured to determine the cell to be equalized as a cell to be equalized according to a voltage difference of the cell, and send a third equalization control signal to the first switch module and a fourth equalization control signal to the second switch module when the voltage difference of the cell is greater than a second set threshold; the first switch module is used for controlling the equalization resistor to be connected to two ends of the corresponding battery cell to be equalized according to the third equalization control signal, and the second switch module is used for controlling the equalization resistor to be disconnected from the equalization bus according to the fourth equalization control signal; the first set threshold is greater than the second set threshold.

7. The equalization circuit of claim 5, wherein the control module comprises a signal processing unit and a switch control unit, the signal processing unit is connected with the first sampling module and the switch control unit, the switch control unit is connected with the first switch module and the second switch module, the signal processing unit is used for outputting a control signal after processing and analyzing a voltage signal output by the first sampling module, and the switch control unit is used for outputting a switch control signal according to the control signal so as to control the first switch module and the second switch module to operate.

8. The equalization circuit of claim 7, wherein the switch control unit further comprises a detection subunit, the detection subunit being connected to the first switch module, the second switch module, and the signal processing unit, the detection subunit being configured to feed back an action duration of the first switch module and the second switch module to the signal processing unit.

9. The equalization circuit of claim 4, further comprising a second sampling module coupled to the first bus, the second bus, and the control module, the second sampling module configured to collect voltages of the first bus and the second bus, the control module further configured to control the first switching module and the second switching module based on a voltage signal output by the second sampling module.

10. An energy storage device comprising an equalization circuit as claimed in any of claims 1-9.