Balancing device, balancing method and battery system

Abstract

The present invention discloses a balancing device, a balancing method and a battery system. When balancing a first battery cluster and a second battery cluster, the balancing device can be electrically connected to the first battery cluster and the second battery cluster, and when a control unit in the balancing device obtains a first voltage of the first battery cluster and a second voltage of the second battery cluster, the control unit can control the connection relationship of each balancing resistor at least according to the first voltage and the second voltage to adjust the resistance value of the balancing unit, thereby achieving balancing of the first battery cluster and the second battery cluster, so as to solve the problems of loop current and uneven current generated when the first battery cluster and the second battery cluster are connected to the battery system.

Description

Technical Field

[0001] The present invention relates to the field of battery technology, and in particular to an equalizing device, an equalizing method and a battery system. Background Art

[0002] A battery energy storage system may include multiple battery clusters connected in parallel. In the process of incorporating multiple battery clusters into the battery energy storage system, it is necessary to solve the problems of uneven current and loop current between battery clusters caused by differences in battery internal resistance, battery capacity, and connection resistance. If these problems are not solved, it may cause overload of cables and components in a battery cluster branch, which in turn may cause excessive heat generation in the battery cluster branch, causing safety problems and may also reduce the service life of the battery cluster in the battery cluster branch. Summary of the invention

[0003] The embodiments of the present invention provide a balancing device, a balancing method and a battery system for balancing a battery cluster to solve at least one of the problems of loop current and uneven current.

[0004] In a first aspect, an embodiment of the present invention provides a balancing device, the balancing device being used to: electrically connect to a first battery cluster to be balanced and a second battery cluster to be balanced when performing balancing processing on the first battery cluster and the second battery cluster to be balanced;

[0005] The balancing device comprises: a control unit and a balancing unit which are electrically connected; the balancing unit comprises a plurality of balancing resistors;

[0006] The control unit is used for:

[0007] acquiring a first voltage of the first battery cluster and a second voltage of the second battery cluster;

[0008] The connection relationship of each of the equalizing resistors is controlled at least according to the first voltage and the second voltage to adjust the resistance value of the equalizing unit.

[0009] In a second aspect, an embodiment of the present invention provides a battery system, including: a plurality of battery clusters;

[0010] Each of the battery clusters is subjected to equalization processing by using the equalization device provided in the embodiment of the present invention.

[0011] In a third aspect, an embodiment of the present invention provides a balancing method, which is implemented by using the above-mentioned balancing device provided by the embodiment of the present invention. The balancing method includes:

[0012] When the balancing device is electrically connected to a first battery cluster to be balanced and a second battery cluster to be balanced respectively, a control unit acquires a first voltage of the first battery cluster and a second voltage of the second battery cluster;

[0013] The control unit controls the connection relationship of each equalizing resistor at least according to the first voltage and the second voltage, so as to adjust the resistance value of the equalizing unit.

[0014] The beneficial effects of the present invention are as follows:

[0015] In the balancing device, balancing method and battery system provided by the embodiments of the present invention, when balancing the first battery cluster and the second battery cluster, the balancing device can be electrically connected to the first battery cluster and the second battery cluster, and when the control unit in the balancing device obtains the first voltage of the first battery cluster and the second voltage of the second battery cluster, it can control the connection relationship of each balancing resistor at least according to the first voltage and the second voltage to adjust the resistance value of the balancing unit, thereby achieving balancing of the first battery cluster and the second battery cluster, so as to solve the problems of loop current and uneven current generated when the first battery cluster and the second battery cluster are connected to the battery system. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of the structure of an equalizing device provided in an embodiment of the present invention;

[0017] Figure 2 A schematic diagram of a specific structure of a balancing unit provided in an embodiment of the present invention;

[0018] Figure 3 A schematic diagram of the structure of another balancing device provided in an embodiment of the present invention;

[0019] Figure 4 It is a three-dimensional schematic diagram of a box provided in an embodiment of the present invention;

[0020] Figure 5 It is a three-dimensional schematic diagram of another box provided in an embodiment of the present invention;

[0021] Figure 6 A schematic diagram of the structure of a battery system provided in an embodiment of the present invention;

[0022] Figure 7 A schematic diagram of balancing battery cluster 1 and battery cluster 2 provided in an embodiment of the present invention;

[0023] Figure 8 A schematic diagram of balancing battery cluster 2 and battery cluster 3 provided in an embodiment of the present invention;

[0024] Fig. 9 The present invention provides a flow chart of a balancing method according to an embodiment of the present invention.

[0025] 10-balancing unit, 11-balancing branch, 20-control unit, 30-current acquisition unit, 40-overcurrent protection unit, 50-heat dissipation unit, 60-temperature detection unit, 70-power processing unit, 80-display, 90-box, 91-terminal block, 92-first switch, 93-second switch, 94-auxiliary switch, 95-shutter, 96-debugging interface, 97-handle, 101-first end of the balancing unit, m-balancing device, T1-positive copper bar, T2-negative copper bar, Z1-first main switch, Z2-second main switch, F0-auxiliary switch, k1-first switch, k2-second switch, k3-third switch, N1-first node, N2-second node, N3-third node, N4-fourth node, P1-first interface, P2-second interface, P3-third interface, P4-fourth interface, R-balancing resistor. DETAILED DESCRIPTION

[0026] The specific implementation of the equalization device, equalization method and battery system provided by the embodiment of the present invention will be described in detail below in conjunction with the accompanying drawings. It should be noted that the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0027] The embodiment of the present invention provides a balancing device, such as Figure 1 As shown, the balancing device m is used to: electrically connect the first battery cluster B1 and the second battery cluster B2 when performing balancing processing on the first battery cluster B1 to be balanced and the second battery cluster B2 to be balanced;

[0028] The balancing device m comprises: a control unit 20 and a balancing unit 10 which are electrically connected; the balancing unit 10 comprises a plurality of (ie, two or more) balancing resistors (not shown in the figure);

[0029] The control unit 20 is used for:

[0030] Acquire a first voltage of the first battery cluster B1 and a second voltage of the second battery cluster B2;

[0031] The connection relationship of each equalizing resistor is controlled at least according to the first voltage and the second voltage to adjust the resistance value of the equalizing unit 10 .

[0032] In this way, when performing balancing processing on the first battery cluster and the second battery cluster, the balancing device can be electrically connected to the first battery cluster and the second battery cluster, and the control unit in the balancing device can control the connection relationship of each balancing resistor at least according to the first voltage and the second voltage when obtaining the first voltage of the first battery cluster and the second voltage of the second battery cluster, so as to adjust the resistance value of the balancing unit, thereby achieving balancing processing on the first battery cluster and the second battery cluster, so as to solve the problems of loop current and uneven current generated when the first battery cluster and the second battery cluster are connected to the battery system.

[0033] Optionally, in an embodiment of the present invention, if Figure 1 As shown, the balancing unit 10, the first battery cluster B1 and the second battery cluster B2 can form a balancing loop;

[0034] In this balancing circuit, if the voltage of the first battery cluster B1 is greater than the voltage of the second battery cluster B2, the first battery cluster B1 can be discharged and the second battery cluster B2 can be charged, so that the voltage of the first battery cluster B1 decreases and the voltage of the second battery cluster B2 increases, thereby reducing the voltage difference between the first battery cluster B1 and the second battery cluster B2 to achieve the purpose of balancing.

[0035] On the contrary, if the voltage of the first battery cluster B1 is lower than the voltage of the second battery cluster B2, the first battery cluster B1 can be charged and the second battery cluster B2 can be discharged, so that the voltage of the first battery cluster B1 increases and the voltage of the second battery cluster B2 decreases, thereby reducing the voltage difference between the first battery cluster B1 and the second battery cluster B2 to achieve the purpose of balancing.

[0036] In this way, an active balancing function can be achieved, thereby reducing energy waste during the balancing process.

[0037] Optionally, in the embodiment of the present invention, when performing balancing processing on the first battery cluster and the second battery cluster, the balancing device may be electrically connected to the first battery cluster and the second battery cluster;

[0038] When the balancing process is not performed on the first battery cluster and the second battery cluster, the balancing device may be disconnected from the first battery cluster and the second battery cluster.

[0039] In this way, the equalizing device can be repeatedly used to perform equalization processing for different battery clusters, avoiding the complexity of the battery system structure caused by each battery cluster having its own equalization circuit. At the same time, the manufacturing cost of the battery system can be reduced on the basis of eliminating the loop current.

[0040] Optionally, in the embodiment of the present invention, before controlling the connection relationship of each balancing resistor at least according to the first voltage and the second voltage, the control unit is further configured to:

[0041] calculating a voltage difference between the first voltage and the second voltage;

[0042] When the voltage difference is greater than a third preset value, determining that the first battery cluster and the second battery cluster need to be equalized;

[0043] When the voltage difference is not greater than the third preset value, it is determined that there is no need to perform balancing processing on the first battery cluster and the second battery cluster.

[0044] The third preset value may be, but is not limited to, 5V, and may also be set to other values ​​according to actual needs, such as, but not limited to, 8V or 4V, etc., which are not limited here.

[0045] In this way, it can be determined based on the voltage difference whether balancing processing is required, so that when balancing processing is required, the resistance of the balancing unit is adjusted, and when balancing processing is not required, the resistance of the balancing unit is not adjusted, which is beneficial to reduce the power consumption of the control unit and further reduce the power consumption of the balancing device.

[0046] Furthermore, optionally, in the embodiment of the present invention, the condition for determining the end of equalization may include: the voltage difference is not greater than a third preset value.

[0047] That is to say, taking the case where the voltage of the first battery cluster is greater than the voltage of the second battery cluster as an example, through balancing processing, the voltage of the first battery cluster is reduced and the voltage of the second battery cluster is increased, so that the difference between the two gradually decreases. When it decreases to the third preset value, it can be considered that the difference between the two is small, and the possibility of generating a loop current is low (or no loop current will be generated), so the balancing processing can be ended at this time, thereby completing the balancing processing of the first battery cluster and the second battery cluster.

[0048] Optionally, in an embodiment of the present invention, if Figure 1 As shown, the balancing device further includes: a first interface P1, a second interface P2, a third interface P3 and a fourth interface P4;

[0049] The first interface P1 is electrically connected to the first output pole s11 of the first battery cluster B1, the second interface P2 is electrically connected to the second output pole s12 of the first battery cluster B1, the third interface P3 is electrically connected to the first output pole s21 of the second battery cluster B2, and the fourth interface P4 is electrically connected to the second output pole s22 of the second battery cluster B2;

[0050] The equalization unit 10 is located between the first interface P1 and the third interface P3;

[0051] The control unit 20 is also electrically connected to the first interface P1 , the second interface P2 , the third interface P3 and the fourth interface P4 , respectively.

[0052] In this way, the four interfaces can be electrically connected to the two output electrodes of the first battery cluster and the two output electrodes of the second battery cluster respectively, so that the balancing device can be electrically connected to the first battery cluster and the second battery cluster respectively, thereby achieving balancing processing for the first battery cluster and the second battery cluster.

[0053] Optionally, in the embodiment of the present invention, the first output pole (such as s11 and s21) may be a positive pole, and the second output pole (such as s12 and s22) may be a negative pole. Figure 1 As shown; or, the first output pole is negative and the second output pole is positive, which is not shown in the figure; it can be set according to actual needs.

[0054] It should be noted that when the first output pole is the positive pole and the second output pole is the negative pole, it means that the balancing unit is arranged between the positive pole of the first battery cluster and the positive pole of the second battery cluster; since the potential of the positive pole is higher than the potential of the negative pole, such an arrangement can avoid leakage of the positive poles of the first battery cluster and the second battery cluster, thereby improving the safety during the balancing process.

[0055] Optionally, in an embodiment of the present invention, if Figure 2 As shown, the balancing unit 10 includes: a plurality of parallel balancing branches 11, each balancing branch 11 includes: a first switch k1, a second switch k2 and a balancing resistor R, and the balancing resistor R is electrically connected between the first switch k1 and the second switch k2;

[0056] Among them, combined Figure 2 As shown, if the upper portion of the balancing resistor R has a first end and the lower portion has a second end, then the first switch k1 in each balancing branch 11 can be electrically connected to the first end of the corresponding balancing resistor R, and the second switch k2 in each balancing branch 11 can be electrically connected to the second end of the corresponding balancing resistor R;

[0057] A third switch k3 is provided between any two adjacent balancing branches 11, and the third switch k3 is used to: when closed, control the balancing resistors R in the two adjacent balancing branches 11 to be connected in series;

[0058] Among them, combined Figure 2 As shown, a first end of the third switch k3 is electrically connected to a first node N1 in one of the balancing branches 11, and a second end of the third switch k3 is electrically connected to a second node N2 in another balancing branch 11; wherein, for each balancing branch 11: the first node N1 is a node between the first switch k1 and the balancing resistor R, and the second node N2 is a node between the second switch k2 and the balancing resistor R; and, for an intermediate balancing branch with balancing branches 11 disposed on opposite sides: the first node N1 and the second node N2 are both electrically connected to a third switch k3;

[0059] Each first switch k1, each second switch k2 and each third switch k3 are electrically connected to the control unit 20, and the control unit 20 is specifically used for:

[0060] By controlling the on and off of each first switch k1 , each second switch k2 , and each third switch k3 , the connection relationship of each balancing resistor R is controlled to adjust the resistance value of the balancing unit 10 .

[0061] For example, Figure 2 As shown, three balancing branches are shown in the figure, but in actual situations, the number of balancing branches is not limited to three, and can also be two, four, five or six or more, which can be set according to actual needs and is not limited here;

[0062] For the three balancing branches 11: the first switches k1 are electrically connected to the first end on the upper side of the balancing resistor R, and the second switches k2 are electrically connected to the second end on the lower side of the balancing resistor R;

[0063] For the balancing branch 11 on the left side and the middle balancing branch 11 in the figure: the third switch k3 is set between the second node N2 of the balancing branch 11 on the left side and the first node N1 of the middle balancing branch 11; for the balancing branch 11 on the right side and the middle balancing branch 11 in the figure: the third switch k3 is set between the first node N1 of the balancing branch 11 on the right side and the second node N2 of the middle balancing branch 11; so for the middle balancing branch 11: the third switch k3 connected to the first node N1 is only the third switch k3 on the left side of the figure, and the third switch k3 connected to the second node N2 is only the third switch k3 on the right side of the figure.

[0064] Continue to combine Figure 2 As shown, if three equalizing resistors R need to be connected in parallel, the control unit 20 can control each first switch k1 and each second switch k2 to be closed, and control each third switch k3 to be opened;

[0065] If two of the balancing resistors R (assuming that they are the balancing resistor R in the left balancing branch 11 and the balancing resistor R in the middle balancing branch 11) need to be connected in series, the control unit 20 can control the first switch k1 in the left balancing branch 11, the third switch k3 on the left, and the second switch k2 in the middle balancing branch 11 to be closed, and the remaining first switches k1, the remaining second switches k2, and the remaining third switches k3 are all opened;

[0066] If three balancing resistors R need to be connected in series, the control unit 20 can control the first switch k1 in the left balancing branch 11, the third switch k3 on the left, the second switch k2 in the middle balancing branch 11, the third switch k3 on the right, and the second switch k2 in the right balancing branch 11 to be closed, and the remaining first switches k1 and the remaining second switches k2 are all disconnected.

[0067] Specifically, in the embodiment of the present invention, the rules (such as resistance value and rated power) of the balancing resistors may be the same, or may be different. The rules may be set according to actual needs and are not limited here.

[0068] In this way, by controlling the closing and opening of the first switch, the second switch, and the third switch, the series connection and parallel connection between the balancing resistors can be achieved, and then the corresponding balancing resistors can be controlled to be connected to the balancing circuit to adjust the resistance value of the balancing unit, thereby achieving balancing processing of the first battery cluster and the second battery cluster.

[0069] Furthermore, by controlling the closing and opening of the first switch, the second switch, and the third switch, when the rules of the three balancing resistors are the same, five-level switching of the resistance in the balancing circuit can be achieved. When the rules of the three balancing resistors are different, the switching resistance level can reach more than 10 levels. In this way, a wider balancing pressure difference range and a smoother balancing current can be achieved without changing the structure of the balancing device.

[0070] In addition, since the first switch, the second switch and the third switch are provided in the balancing unit, the probability that the balancing loop cannot be disconnected in time can be greatly reduced, the flexibility of adjusting the resistance of the balancing unit is improved, and the safety of the battery system can also be improved.

[0071] Specifically, the rated current of each first switch and each second switch can be set to the same, for example but not limited to 100A, and the rated current of each third switch can be set to be different from the rated current of the first switch, for example but not limited to 50A; the specific settings can be made according to actual needs and are not limited here.

[0072] Optionally, in an embodiment of the present invention, if Figure 3 As shown, the balancing device further includes: a current collection unit 30;

[0073] The current collection unit 30 is electrically connected to the control unit 20, and the current collection unit 30 is used to: collect the current flowing through the balancing unit 10 (that is, the current in the balancing loop) and transmit it to the control unit 20;

[0074] The control unit 20 is further configured to control each of the first switches k1 , each of the second switches k2 , and each of the third switches k3 to be disconnected when the collected current exceeds a first preset value.

[0075] Among them, Figure 3 In order to avoid an overly complicated structure, the control end of the first switch k1, the control end of the second switch k2, and the control end of the third switch k3 are not connected to the terminals on the left side of the control unit 20 (shown in the dotted frame 1) through wires, but this does not mean that the control end of the first switch k1, the control end of the second switch k2, and the control end of the third switch k3 are not electrically connected to the control unit 20; in actual situations, the control end of the first switch k1, the control end of the second switch k2, and the control end of the third switch k3 are electrically connected to the terminals on the left side of the control unit 20 (shown in the dotted frame 1) respectively, but they are not shown in the figure.

[0076] Furthermore, the first preset value may be set to 30A, and may also be set to other values, such as but not limited to 35A or 40A, etc. It may be set according to actual needs and is not limited here.

[0077] In addition, when the balancing device includes the second interface P2 and the fourth interface P4, the current acquisition unit 30 may be located between the second interface P2 and the fourth interface P4.

[0078] In this way, when the current exceeds the first preset value, it means that the current in the balancing loop is large. If this high current state continues, it may be dangerous. Therefore, in order to improve the safety of the balancing unit and even the balancing device, the control unit can control the first switches, the second switches, and the third switches to be disconnected to cut off the balancing loop.

[0079] Specifically, in the embodiment of the present invention, the current acquisition unit may include a Hall sensor; that is, the function of the current acquisition unit may be implemented by the Hall sensor.

[0080] Of course, in specific implementation, other structures may be used to implement the function of the current acquisition unit, so the specific structure of the current acquisition unit is not limited here.

[0081] In this way, the current value and direction of the current can be collected by the Hall sensor and sent to the control unit so that the control unit can make corresponding judgments and processing.

[0082] Optionally, in an embodiment of the present invention, if Figure 3 As shown, the balancing device further includes: an overcurrent protection unit 40, a heat dissipation unit 50 and / or a temperature detection unit 60;

[0083] The overcurrent protection unit 40 is used to disconnect when the current flowing through the balancing unit 10 (that is, the current on the balancing loop) exceeds a second preset value;

[0084] The temperature detection unit 60 is electrically connected to the control unit 20 , and the temperature detection unit 60 is used to: collect the temperature of the equalization unit 10 and transmit it to the control unit 20 ;

[0085] The heat dissipation unit 50 is electrically connected to the control unit 20, and the control unit 20 is also used to: obtain the temperature of the balancing unit 10; control the opening and closing of the heat dissipation unit 50 according to the temperature; and control the connection relationship of each balancing resistor R according to the first voltage, the second voltage and the temperature.

[0086] Specifically, Figure 3 As shown, when the current acquisition unit 30 is included in the equalizing device, the current acquisition unit 30 and the overcurrent protection unit 40 can be connected in series between the second interface P2 and the fourth interface P4;

[0087] Furthermore, the overcurrent protection unit may include but is not limited to a fuse, that is, a fuse is used to implement the function of the overcurrent protection unit; of course, the overcurrent protection unit may also be implemented using other structures that can achieve its function, which is not limited here.

[0088] The second preset value can be set according to actual needs and is not limited here; and there is no direct relationship between the second preset value and the first preset value, and their specific values ​​will not affect each other.

[0089] Thus, when the current in the balancing loop exceeds the second preset value, it indicates that the current in the balancing loop is high. To improve the safety of the balancing device and avoid damage to the structure in the balancing device, the overcurrent protection unit may be disconnected to protect the balancing device.

[0090] In addition, the current acquisition unit and the overcurrent protection unit can provide dual protection for the balancing device, thereby maximizing the safety of the balancing device during use.

[0091] Specifically, the heat dissipation unit may include, but is not limited to, a fan. Of course, it may also be other structures that can realize the function of the heat dissipation unit, which is not limited here.

[0092] The number of heat dissipation units is not limited to Figure 3 The number is one as shown in the figure, and may also be two, three or more, and may be set according to actual needs, which is not limited here.

[0093] In this way, by setting the heat dissipation unit, when the internal temperature of the balancing device is high, it can be turned on to dissipate heat for the balancing device, thereby avoiding damage to other structures due to excessive temperature, thereby improving the safety of the balancing device.

[0094] Specifically, the temperature detection unit may include, but is not limited to, a temperature probe, and may also be other structures that can realize the function of the temperature detection unit, which is not limited here.

[0095] The number of temperature detection units may be the same as the number of balancing resistors in the balancing unit, or the number of temperature detection units may be less than the number of balancing resistors. The number may be set according to actual needs and is not limited here.

[0096] Let me explain. Figure 3 The number of temperature detection units shown in the figure does not represent the number of settings in actual situations. It only illustrates that the balancing device includes the temperature detection units.

[0097] In this way, by setting the temperature detection unit, the temperature of the balancing resistor can be detected, and then the temperature change of the balancing resistor can be monitored in real time, so that the control unit can control the heat dissipation unit, each first switch, each second switch and each third switch accordingly based on the detected temperature.

[0098] Optionally, if multiple temperature detection units are provided, each temperature detection unit will detect a temperature at the same time. At this time, the control unit can control the heat dissipation unit, each first switch, each second switch and each third switch accordingly based on the highest temperature among these temperatures.

[0099] Optionally, in an embodiment of the present invention, if Figure 3 As shown, the balancing device further includes: a first main switch Z1 located between the balancing unit 10 and the first interface P1, and a second main switch Z2 located between the second interface P2 and the fourth interface P4;

[0100] The first main switch Z1 and the second main switch Z2 are both used for:

[0101] It is opened when the balancing process is finished, and is closed when the first port P1 and the second port P2 are both electrically connected to the first battery cluster B1 , and the third port P3 and the fourth port P4 are both electrically connected to the second battery cluster B2 .

[0102] The first main switch Z1 may be located between the first terminal 101 of the balancing unit 10 and the first interface P1. Figure 3 shown.

[0103] That is, after the balancing device is electrically connected to the first battery cluster and the second battery cluster, the first main switch and the second main switch can be closed, and at the same time, the control unit controls the closing and opening of the first switch, the second switch and the third switch in the balancing unit based on the voltage difference (or based on the voltage difference and the temperature), so as to construct a balancing loop to achieve balancing processing of the first battery cluster and the second battery cluster;

[0104] At the end of the balancing process, the balancing device is disconnected from the first battery cluster and the second battery cluster to disconnect the balancing loop.

[0105] In this way, by setting the first main switch and the second main switch, the on-off control of the balancing circuit can be realized, and the balancing circuit can be disconnected in time when the balancing is completed, thereby improving the safety of the battery system.

[0106] Optionally, in an embodiment of the present invention, if Figure 3 As shown, the node between the first main switch Z1 and the balancing unit 10 is the third node N3, and the node between the second main switch Z2 and the fourth interface P4 is the fourth node N4;

[0107] The equalizing device further includes: an auxiliary switch F0 and a power processing unit 70 sequentially arranged between the third node N3 and the fourth node N4;

[0108] The power processing unit 70 is also electrically connected to the control unit 20;

[0109] The auxiliary switch F0 is used to: disconnect when the balancing process is finished, and close when the first interface P1 and the second interface P2 are both electrically connected to the first battery cluster B1, and the third interface P3 and the fourth interface P4 are both electrically connected to the second battery cluster B2;

[0110] The power processing unit 70 is used for:

[0111] When the auxiliary switch F0 , the first main switch Z1 and the second main switch Z2 are all closed and the voltage of the first battery cluster B1 is greater than the voltage of the second battery cluster B2 , the voltage provided by the first battery cluster B1 is converted to obtain the power supply voltage of the control unit 20 and power the control unit 20 .

[0112] Among them, Figure 3 As shown, when a current acquisition unit 30 is provided between the second interface P2 and the fourth interface P4, the fourth node N4 is located between the current acquisition unit 30 and the second main switch Z2.

[0113] And, if Figure 3As shown, when the auxiliary switch F0, the first main switch Z1 and the second main switch Z2 are all closed, the loop formed by the first interface P1, the second interface P2, the third node N3 and the fourth node N4 includes the first battery cluster B1 and the power processing unit 70. At this time, the power processing unit 70 can convert the first voltage provided by the first battery cluster B1 into a driving voltage that can be used by the control unit 20. For example, the power processing unit 70 converts the high-voltage signal provided by the first battery cluster B1 into a low-voltage signal, and then outputs it to the control unit 20, so as to provide the control unit 20 with the electric energy required for operation. The control unit 20 can work normally based on the electric energy, thereby realizing the balancing process.

[0114] In this way, by setting up the auxiliary switch and the power processing unit, the control unit can be provided with the electric energy required for its operation. While ensuring that the control unit can work normally, it can also avoid the need to additionally set up a power supply for the balancing device, thereby simplifying the structure of the balancing device and reducing the manufacturing cost of the balancing device. At the same time, it can also achieve effective utilization of energy and avoid waste.

[0115] And, optionally, in an embodiment of the present invention, if Figure 3 As shown, the power processing unit 70 can also supply power to the heat dissipation unit 50 , so that the heat dissipation unit 50 works under the control of the control unit 20 and driven by the electrical signal provided by the power processing unit 70 .

[0116] Of course, optionally, a power supply may be additionally provided in the balancing device, which is not shown in the figure, and the power supply may provide the control unit with the electric energy required for operation.

[0117] At this time, the balancing device may include a power processing unit and an auxiliary switch, or may not include the power processing unit and the auxiliary switch. The specific configuration may be based on actual needs and is not limited here.

[0118] In this way, the design flexibility of the balancing device can be improved, and at the same time, when the first battery cluster and the second battery cluster are abnormal and cannot provide electric energy, the balancing device can still be guaranteed to work normally.

[0119] Optionally, in an embodiment of the present invention, the power processing unit may include: a voltage converter (i.e., a DC / DC converter); of course, the power processing unit may also include other structures that can be used to implement the functions of the power processing unit, which can be specifically configured according to actual needs and are not limited here.

[0120] Optionally, in the embodiment of the present invention, the first main switch, the second main switch and the auxiliary switch can be closed and opened by manual control, or closed and opened by the control unit. The specific settings can be made according to actual needs and are not limited here.

[0121] Optionally, in the embodiment of the present invention, the control unit may include: a central processing unit or a microprocessor or other structure that can implement a logic control function, which may be specifically configured according to actual needs and is not limited here.

[0122] Optionally, in an embodiment of the present invention, if Figure 3 As shown, the equalizing device further includes: a display 80 electrically connected to the control unit 20;

[0123] The display 80 is used to display the first voltage, the second voltage, and the temperature under the control of the control unit 20 .

[0124] Of course, in addition to displaying the first voltage, the second voltage and the temperature, the display can also display the voltage difference, the current in the balancing circuit, the on-off status of each first switch, each second switch and each third switch, and the operating status of the cooling unit, etc. As long as the information is related to the balancing process, it can be displayed in the display.

[0125] Thus, through the information displayed on the display, the real-time status of the first battery cluster and the second battery cluster, the execution process of the balancing process, and the result of the balancing process can be fully understood, so that the balancing process can be fully understood.

[0126] Optionally, in an embodiment of the present invention, if Figure 4 As shown, the balancing device further includes a box 90, and the control unit and the balancing unit are both located in the box 90;

[0127] The box body 90 is provided with a terminal row 91 , which is electrically connected to the first battery cluster (not shown in the figure) and the second battery cluster (not shown in the figure) respectively.

[0128] in, Figure 4 What is shown is the structure of the box body, and the structure inside the box body is not shown.

[0129] Furthermore, the terminal block 91 may be disposed on the outer surface of the box body 90, such as Figure 4 As shown, it is arranged on the side C1 of the box body 90; of course, it is not limited to this, and here it is just Figure 4 The example shown is for illustration only, and the specific location of the terminal block 91 can be set according to actual needs.

[0130] In this way, by setting the terminal block, the electrical connection with the first battery cluster and the second battery cluster can be easily achieved, which reduces the difficulty of the operator's work and the requirements for the operator, and has strong ease of operation.

[0131] Optionally, in an embodiment of the present invention, if Figure 5As shown, the box 90 is provided with a first switch component 92, a second switch component 93 and an auxiliary switch component 94, and the balancing device includes a first main switch (not shown in the figure), a second main switch (not shown in the figure) and an auxiliary switch (not shown in the figure), the first switch component 92 is connected to the first main switch, the second switch component 93 is connected to the second main switch, and the auxiliary switch component 94 is connected to the auxiliary switch;

[0132] like Figure 5 As shown, the display 80 is arranged on the surface of the box 90; the balancing device includes: a first interface (not shown in the figure), a second interface (not shown in the figure), a third interface (not shown in the figure) and a fourth interface (not shown in the figure), and the first interface, the second interface, the third interface, and the fourth interface are all located in the terminal block 91;

[0133] like Figure 5 As shown, the box 90 is also provided with a shutter 95;

[0134] like Figure 4 As shown, the box body 90 is provided with a through hole for placing the heat dissipation unit 50, and the heat dissipation unit 50 is located in the through hole.

[0135] in, Figure 4 The side C1 shown in Figure 5 The side C2 shown in the figure is two opposite sides of the box body 90, so that the shutter 95 and the heat dissipation unit 50 are respectively arranged on the two opposite sides; in this way, it is convenient to form a heat dissipation channel, improve the heat dissipation effect, avoid overheating of the balancing device, and thus improve the safety of the use of the balancing device.

[0136] Also, the display 80 setting can be set in Figure 5 On the side C2 shown in the figure, of course, it is not limited to this. The specific setting position of the display 80 can be set according to actual needs and is not limited here. By setting the display 80 on the surface of the box, it is convenient for the operator to read relevant information from the display.

[0137] Specifically, a sealing gasket is provided between the heat dissipation unit and the through hole, which is not shown in the figure. In this way, the sealing of the box can be increased, and dust can be reduced from entering the interior of the balancing device, thereby preventing dust from adversely affecting the normal operation of the internal structure of the balancing device, thereby improving the reliability of the balancing device.

[0138] Specifically, Figure 5 As shown, a debugging interface 96 is provided on the surface of the box body 90, and the debugging interface 96 is electrically connected to the control unit and an external device (not shown in the figure), respectively. The debugging interface 96 is used to transmit the information provided by the external device to the control unit, so that the external device can update and improve the data such as programs and parameters stored in the control unit.

[0139] In this way, the data in the control unit can be updated and improved according to actual needs, so as to upgrade the program in the control unit and improve the function of the control unit, thereby improving the performance of the balancing device.

[0140] Specifically, Figure 4 and Figure 5 As shown, a handle 97 is provided on the surface of the box body 90, and two handles 97 may be provided, which are respectively provided on two opposite sides of the box body 90, such as Figure 4 The side C3 and Figure 5 Side C4 shown in;

[0141] Among them, Figure 4 and Figure 5 As shown, the side where the two handles 97 are located is different from the side where the heat dissipation unit 50 and the display 80 are located; of course, they can also be set to be the same, and can be specifically set according to actual needs, which is not limited here.

[0142] In this way, by providing the handle, it is convenient for an operator to carry the balancing device so as to move the setting position of the balancing device.

[0143] Specifically, Figure 4 and Figure 5 As shown, the box body 90 may be, but is not limited to, a rectangular parallelepiped structure formed by welding sheet metal parts;

[0144] The box body may include: a frame with a bottom plate and an opening and a cavity, and a box cover covering the opening, wherein the area of ​​the box cover may be larger than the area of ​​the opening, and the box cover is provided with a folded edge, which can be bent to the side of the frame away from the cavity.

[0145] In this way, the sealing effect of the box can be increased by setting the folded edge; the strength of the box can be increased by welding sheet metal parts, avoiding damage to the internal structure (such as the balancing unit and the control unit) caused by external impact, thereby improving the reliability of the balancing device.

[0146] Note that, optionally, the structure of the box is not limited to Figure 4 and Figure 5 As shown, other structures can also be set according to actual needs and are not limited here.

[0147] Based on the same inventive concept, an embodiment of the present invention provides a battery system, such as Figure 6 As shown, it includes: a plurality of battery clusters (such as B1, B2 and B3 shown in the figure);

[0148] Each battery cluster is subjected to equalization processing by using the above-mentioned equalization device provided in the embodiment of the present invention.

[0149] Optionally, in the embodiment of the present invention, the number of battery clusters included in the battery system is not limited to Figure 6 The three shown in the figure may also be four, five or more, and may be specifically set according to actual needs and is not limited here.

[0150] Optionally, in an embodiment of the present invention, each battery cluster in the battery system may be connected in parallel (eg Figure 6 As shown), of course, it can also be connected in series (not shown in the figure), and can be specifically set according to actual needs and is not limited here.

[0151] Optionally, in an embodiment of the present invention, if Figure 6 As shown, the battery system may include: a positive copper busbar T1 and a negative copper busbar T2. When the battery clusters are connected in parallel, the positive electrode of the battery cluster connected to the battery system (as shown on the left side of the battery cluster in the figure) can be electrically connected to the positive copper busbar T1, and the negative electrode (as shown on the right side of the battery cluster in the figure) can be electrically connected to the negative copper busbar T2.

[0152] The following example illustrates the process of connecting each battery cluster to the battery system.

[0153] For example, a battery system includes three battery clusters, which are respectively denoted as battery cluster B1, battery cluster B2 and battery cluster B3. Figure 7 and Figure 8 As shown, the process of connecting these three battery clusters to the battery system may include:

[0154] Assume that the voltages of the three battery clusters are arranged in order from high to low: battery cluster B1, battery cluster B2, and battery cluster B3, then:

[0155] like Figure 7 As shown, the positive electrode s11 of the battery cluster B1 is first electrically connected to the positive copper bar T1, and the negative electrode s12 is electrically connected to the negative copper bar T2, so that the battery cluster B1 is connected to the battery system, and the positive electrode s11 and the negative electrode s12 of the battery cluster B1, as well as the positive electrode s21 and the negative electrode s22 of the battery cluster B2 are all connected to the terminal block of the equalizing device m (not shown in the figure), so that the equalizing device m is electrically connected to the battery cluster B1 and the battery cluster B2 respectively; the equalizing device m is used to perform equalization processing on the battery cluster B1 and the battery cluster B2; after the equalization processing is completed, the positive electrode s11 and the negative electrode s12 of the battery cluster B1, as well as the positive electrode s21 and the negative electrode s22 of the battery cluster B2 are all disconnected from the terminal block of the equalizing device m;

[0156] The positive electrode s21 of the battery cluster B2 is electrically connected to the positive copper busbar T1, and the negative electrode s22 is electrically connected to the negative copper busbar T2, so as to connect the battery cluster B2 to the battery system;

[0157] like Figure 8As shown, the positive electrode s21 and the negative electrode s22 of the battery cluster B2, and the positive electrode s31 and the negative electrode s32 of the battery cluster B3 are connected to the terminal block of the balancing device m, so that the balancing device m is electrically connected to the battery cluster B2 and the battery cluster B3 respectively; the balancing device m is used to perform balancing processing on the battery cluster B2 and the battery cluster B3; after the balancing processing is completed, the positive electrode s21 and the negative electrode s22 of the battery cluster B2, and the positive electrode s31 and the negative electrode s32 of the battery cluster B3 are disconnected from the terminal block of the balancing device m;

[0158] The positive electrode s31 of the battery cluster B3 is electrically connected to the positive copper bus T1, and the negative electrode s32 is electrically connected to the negative copper bus T2, so that the battery cluster B3 is connected to the battery system. Figure 6 Results shown.

[0159] To clarify, in order to determine the order in which the voltages of the three battery clusters are arranged from high to low, a voltage collector (such as but not limited to a digital multimeter) can be used to test the voltages of the three battery clusters respectively, and then based on the test results, the three battery clusters can be sorted in order from high to low.

[0160] In this way, the battery clusters B1, B2 and B3 connected to the battery system are all battery clusters that have been balanced, so that the voltage difference between the three battery clusters can be very small, thereby avoiding circulation between the battery clusters and improving the safety of the battery system.

[0161] Based on the same inventive concept, an embodiment of the present invention provides a balancing method, such as Fig. 9 As shown, the balancing method is implemented by using the above-mentioned balancing device provided in the embodiment of the present invention, and includes:

[0162] S901, when a balancing device is electrically connected to a first battery cluster to be balanced and a second battery cluster to be balanced respectively, a control unit acquires a first voltage of the first battery cluster and a second voltage of the second battery cluster;

[0163] S902: The control unit controls the connection relationship of each balancing resistor at least according to the first voltage and the second voltage to adjust the resistance value of the balancing unit.

[0164] In this way, the connection relationship of each balancing resistor can be controlled at least according to the first voltage and the second voltage to adjust the resistance value of the balancing unit, thereby achieving balancing processing of the first battery cluster and the second battery cluster to solve the loop current and uneven current problems generated when the first battery cluster and the second battery cluster are connected to the battery system.

[0165] In addition, the automatic and smooth switching of the resistance value of the balancing unit in the balancing circuit is realized, and the balancing rate is balanced. Compared with the conventional balancing rate, there is a significant improvement, which can effectively improve the balancing efficiency when the battery system is constructed, and at the same time improve the safety of the battery system.

[0166] Optionally, in the embodiment of the present invention, before controlling the connection relationship of each balancing resistor, the method further includes:

[0167] calculating a voltage difference between the first voltage and the second voltage;

[0168] When the voltage difference is greater than the third preset value, it is determined that the first battery cluster and the second battery cluster need to be balanced.

[0169] In this way, the voltage difference between the first battery cluster and the second battery cluster can be determined through the voltage difference. When the voltage difference is less than or equal to the third preset value, it means that the voltage difference between the two battery clusters is small. If the two battery clusters are connected to the battery system, the possibility of circulating current is low, so there is no need to balance the two battery clusters at this time, and they can be directly connected to the battery system; when the voltage difference is greater than the third preset value, it means that the voltage difference between the two battery clusters is large. If the two battery clusters are connected to the battery system, the possibility of circulating current is large, so it is necessary to balance the battery clusters and connect them to the battery system after the balanced processing.

[0170] Optionally, in the embodiment of the present invention, controlling the connection relationship of each balancing resistor at least according to the first voltage and the second voltage specifically includes:

[0171] calculating a voltage difference between the first voltage and the second voltage;

[0172] The connection relationship of each balancing resistor is controlled at least according to the corresponding relationship between the voltage difference and the preset voltage range.

[0173] In this way, the connection relationship of each equalizing resistor can be controlled at least according to the corresponding relationship between the voltage difference and the preset voltage range, so as to adjust the resistance value of the equalizing unit and realize the equalization processing.

[0174] Optionally, in an embodiment of the present invention, controlling the connection relationship of each balancing resistor at least according to the corresponding relationship between the voltage difference and the preset voltage interval specifically includes:

[0175] The connection relationship of each balancing resistor is controlled according to the corresponding relationship between the voltage difference and the preset voltage interval, and the temperature of the balancing unit.

[0176] The temperature of the balancing unit can be collected by a temperature detection unit in the balancing device. After the temperature is collected, the temperature detection unit sends the collected temperature to the control unit, so that the control unit can obtain the temperature of the balancing unit.

[0177] Optionally, in the embodiment of the present invention, when collecting temperature, the temperature detection unit may collect temperature according to a preset collection cycle, wherein the collection cycle may be set according to actual needs and is not limited here.

[0178] In this way, the resistance value of the balancing unit in the balancing circuit can be automatically and smoothly switched, achieving a balance between the balancing rate and the temperature rise. Compared with the conventional balancing rate, the balancing rate has been greatly improved, thereby effectively improving the balancing efficiency when the battery system is constructed, and at the same time improving the safety of the battery system.

[0179] Optionally, in an embodiment of the present invention, controlling the connection relationship of each balancing resistor according to the corresponding relationship between the voltage difference and the preset voltage interval, and the temperature of the balancing unit, specifically includes:

[0180] When the temperature is lower than the first preset temperature and the voltage difference is higher than the third preset value and lower than the fourth preset value, all the balancing resistors are controlled to be connected in parallel;

[0181] When the temperature is lower than the first preset temperature and the voltage difference is greater than or equal to the fourth preset value and less than the fifth preset value, or when the temperature is greater than or equal to the first preset temperature and lower than the second preset temperature and the voltage difference is greater than the third preset value and less than the fourth preset value, the control part of the balancing resistors are connected in series;

[0182] When the temperature is lower than the first preset temperature and the voltage difference is higher than the fifth preset value, or when the temperature is higher than or equal to the second preset temperature and lower than the third preset temperature and the voltage difference is higher than the third preset value and lower than the fifth preset value, controlling all the balancing resistors to be connected in series;

[0183] When the temperature is greater than or equal to the third preset temperature, the first switch, the second switch and the third switch in the balancing unit are all disconnected to control the electrical connection between the balancing resistors; that is, all the balancing resistors are disconnected from the balancing loop.

[0184] Among them, the first preset temperature can be but not limited to 55°C, the second preset temperature can be but not limited to 60°C, and the third preset temperature can be but not limited to 65°C; of course, the first preset temperature, the second preset temperature and the third preset temperature are not limited to the above values, and can also be set to other values ​​according to actual needs, which are not limited here.

[0185] Furthermore, the fourth preset value may be but is not limited to 50V, and the fifth preset value may be but is not limited to 100V; of course, the fourth preset value and the fifth preset value are not limited to the above values, and may also be set to other values ​​according to actual needs, which are not limited here.

[0186] In this way, the balancing resistor connected to the balancing loop can be selected according to the voltage difference and the temperature, and then the resistance of the balancing unit in the balancing loop can be adjusted, thereby achieving balancing processing for the first battery cluster and the second battery cluster.

[0187] Optionally, in the embodiment of the present invention, the method further includes:

[0188] When the temperature is greater than or equal to the fourth preset temperature and less than the third preset temperature, the control unit controls the heat dissipation unit to turn on;

[0189] The fourth preset temperature is lower than the first preset temperature.

[0190] When the first preset temperature is 55° C., the fourth preset temperature may be, but is not limited to, 45° C.; of course, the fourth preset temperature is not limited to the above values, and may also be set to other values ​​according to actual needs, which is not limited here.

[0191] In this way, it can be determined based on the temperature when to start the heat dissipation unit, so as to dissipate the heat of the balancing unit, avoid the balancing unit from being overheated, and further avoid danger to the balancing device, thereby improving the safety of the balancing device.

[0192] Optionally, in an embodiment of the present invention, when the balancing device is electrically connected to the first battery cluster and the second battery cluster respectively, the first main switch, the second main switch and the auxiliary switch are in a closed state;

[0193] When the balancing process is finished, the first main switch, the second main switch and the auxiliary switch are all in the off state.

[0194] The closing and opening of the first main switch, the second main switch and the auxiliary switch may be, but are not limited to, controlled manually.

[0195] In this way, when the balancing device is electrically connected to the first battery cluster and the second battery cluster respectively, since the first main switch, the second main switch and the auxiliary switch are all in a closed state, the control unit can work under the drive of the electric energy provided by the power processing unit, thereby achieving balancing processing of the battery cluster;

[0196] When the balancing process is finished, since the first main switch, the second main switch and the auxiliary switch are all in the off state to cut off the balancing circuit, it is beneficial to disconnect the balancing device from the battery cluster that has been balanced, and then the same balancing device can be used to continue to balance other battery clusters, thereby realizing the use of one balancing device to balance all battery clusters to be balanced, effectively reducing the balancing cost.

[0197] Optionally, in the embodiment of the present invention, the method further includes:

[0198] The control unit controls the display to display the first voltage, the second voltage, the voltage difference, and the temperature.

[0199] In this way, the information displayed on the display allows the operator to intuitively obtain and observe the balancing process, thereby allowing the operator to fully grasp the information of the battery cluster and provide effective data reference for subsequent maintenance of the battery system.

[0200] The following example illustrates the balancing process.

[0201] by Figure 3 For the balancing unit shown in , the first preset temperature is 55° C., the second preset temperature is 60° C., the third preset temperature is 65° C., the fourth preset temperature is 45° C., the third preset value is 5V, the fourth preset value is 50V, and the fifth preset value is 100V as an example.

[0202] When the balancing device is electrically connected to the first battery cluster B1 and the second battery cluster B2, the first main switch Z1, the second main switch Z2 and the auxiliary switch F0 are controlled to be closed. At this time, the control unit 20 can work under the power provided by the power processing unit 70 to obtain the voltage difference and the temperature of the balancing unit 10. Then, the control unit 20 works according to the following working conditions, which may specifically include:

[0203] Working condition 1: if the temperature of the balancing unit 10 is less than 45° C. and the voltage difference is (5V, 50V), the control unit 20 can control the three first switches k1 and the three second switches k2 to be closed, and the two third switches k3 to be opened, so that the three balancing resistors R are connected in parallel in the balancing loop;

[0204] Working condition 2: if the temperature of the balancing unit 10 is less than 45° C. and the voltage difference is [50V, 100V), the control unit 20 may control any two of the three balancing resistors R to be connected in series in the balancing loop;

[0205] Among them, Figure 3Taking the leftmost balancing resistor R and the middle balancing resistor R as an example, the control unit 20 can control the leftmost first switch k1, the leftmost third switch k3, and the middle second switch k2 to be closed, and the remaining first switches k1, the remaining second switches k2, and the remaining third switches k3 are all opened;

[0206] Working condition 3: if the temperature of the balancing unit 10 is less than 45° C. and the voltage difference is greater than or equal to 100 V, the control unit 20 may control the leftmost first switch k1, the leftmost third switch k3, the rightmost third switch k3 and the rightmost second switch k2 to be closed, and the remaining first switches k1 and the remaining second switches k2 are all opened, so that the three balancing resistors R are connected in series in the balancing loop;

[0207] Working condition 4: if the temperature of the balancing unit 10 is [45°C, 55°C), and the voltage difference is (5V, 50V), on the one hand, the control unit 20 controls the three first switches k1 and the three second switches k2 to be closed, and the two third switches k3 to be opened, so that the three balancing resistors R are connected in parallel in the balancing loop; on the other hand, the control unit 20 controls the heat dissipation unit 50 to be turned on, and the heat dissipation unit 50 is used to dissipate heat for the balancing unit 10;

[0208] Working condition 5: if the temperature of the balancing unit 10 is [45°C, 55°C), and the voltage difference is [50V, 100V), on the one hand, the control unit can control any two of the three balancing resistors to be connected in series in the balancing circuit; on the other hand, the control unit 20 controls the heat dissipation unit 50 to be turned on, and the heat dissipation unit 50 is used to dissipate heat for the balancing unit 10;

[0209] Working condition 6: if the temperature of the balancing unit 10 is [45°C, 55°C), and the voltage difference is greater than or equal to 100V, on the one hand, the control unit 20 can control the leftmost first switch k1, the leftmost third switch k3, the rightmost third switch k3 and the rightmost second switch k2 to be closed, and the remaining first switches k1 and the remaining second switches k2 are all disconnected, so that the three balancing resistors R are connected in series in the balancing loop; on the other hand, the control unit 20 controls the heat dissipation unit 50 to be turned on, and the heat dissipation unit 50 is used to dissipate heat for the balancing unit 10;

[0210] Working condition 7: if the temperature of the balancing unit 10 is [55°C, 60°C), and the voltage difference is (5V, 50V), on the one hand, the control unit 20 can control any two of the three balancing resistors R to be connected in series in the balancing circuit; on the other hand, the control unit 20 controls the heat dissipation unit 50 to be turned on, and the heat dissipation unit 50 is used to dissipate heat for the balancing unit 10;

[0211] Working condition 8: If the temperature of the balancing unit 10 is [60°C, 65°C), and the voltage difference is (5V, 100V), on the one hand, the control unit 20 can control the leftmost first switch k1, the leftmost third switch k3, the rightmost third switch k3 and the rightmost second switch k2 to be closed, and the remaining first switches k1 and the remaining second switches k2 are all disconnected, so that the three balancing resistors R are connected in series in the balancing loop; on the other hand, the control unit 20 controls the heat dissipation unit 50 to be turned on, and the heat dissipation unit 50 is used to dissipate heat for the balancing unit 10.

[0212] It should be noted that in conditions other than the above conditions, the control unit controls the first switches, the second switches and the third switches to be disconnected, indicating that the voltage difference between the two battery clusters is too large or the temperature is too high, so the balancing device is not used for balancing processing.

[0213] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A balancing device, characterized in that: The balancing device is used to: electrically connect to the first battery cluster and the second battery cluster when performing balancing processing on the first battery cluster to be balanced and the second battery cluster to be balanced; The balancing device comprises: a control unit and a balancing unit which are electrically connected; the balancing unit comprises a plurality of balancing resistors; The control unit is used for: acquiring a first voltage of the first battery cluster and a second voltage of the second battery cluster; controlling the connection relationship of the equalizing resistors at least according to the first voltage and the second voltage to adjust the resistance value of the equalizing unit; The balancing device further comprises: a first interface, a second interface, a third interface and a fourth interface; the first interface is electrically connected to the first output pole of the first battery cluster, the second interface is electrically connected to the second output pole of the first battery cluster, the third interface is electrically connected to the first output pole of the second battery cluster, and the fourth interface is electrically connected to the second output pole of the second battery cluster; the balancing unit is located between the first interface and the third interface; the control unit is also electrically connected to the first interface, the second interface, the third interface and the fourth interface respectively; The equalizing device further comprises: an auxiliary switch and a power processing unit connected in series, the power processing unit being also electrically connected to the control unit; The auxiliary switch is used to: disconnect when the balancing process is finished, and close when the first interface and the second interface are both electrically connected to the first battery cluster, and the third interface and the fourth interface are both electrically connected to the second battery cluster; The power processing unit is used to: when the auxiliary switch is closed, the auxiliary switch is connected to the first interface, the power processing unit is connected to the second interface, and the voltage of the first battery cluster is greater than the voltage of the second battery cluster, convert the voltage provided by the first battery cluster to obtain the power supply voltage of the control unit and supply power to the control unit.

2. The equalizing device according to claim 1, characterized in that: The balancing unit comprises: a plurality of parallel balancing branches, each of which comprises: a first switch, a second switch and a balancing resistor, wherein the balancing resistor is electrically connected between the first switch and the second switch; A third switch is provided between any two adjacent balancing branches, and the third switch is used to: when closed, control the balancing resistors in the two adjacent balancing branches to be connected in series; Each of the first switches, each of the second switches, and each of the third switches are electrically connected to the control unit, and the control unit is specifically used to: By controlling the on and off of each of the first switches, each of the second switches and each of the third switches, the connection relationship of each of the balancing resistors is controlled to adjust the resistance value of the balancing unit.

3. The equalizing device according to claim 2, characterized in that: The balancing device further includes: a current collection unit; The current collection unit is electrically connected to the control unit, and the current collection unit is used to: collect the current flowing through the equalization unit and transmit it to the control unit; The control unit is further configured to control each of the first switches, each of the second switches, and each of the third switches to be disconnected when the collected current exceeds a first preset value.

4. The equalizing device according to claim 1, characterized in that: The balancing device further comprises: an overcurrent protection unit, a heat dissipation unit, a temperature detection unit and / or a display; The overcurrent protection unit is used to: disconnect when the current flowing through the equalization unit exceeds a second preset value; The temperature detection unit is electrically connected to the control unit, and the temperature detection unit is used to: collect the temperature of the equalization unit and transmit it to the control unit; The heat dissipation unit is electrically connected to the control unit, and the control unit is further used to: obtain the temperature of the balancing unit; control the opening and closing of the heat dissipation unit according to the temperature; and control the connection relationship of each of the balancing resistors according to the first voltage, the second voltage and the temperature; The display is electrically connected to the control unit, and is used to display the first voltage, the second voltage, and the temperature under the control of the control unit.

5. The equalizing device according to claim 1, characterized in that: The balancing device further comprises: a first main switch located between the balancing unit and the first interface, and a second main switch located between the second interface and the fourth interface; The first main switch and the second main switch are both used for: The interface is opened when the balancing process is finished, and is closed when the first interface and the second interface are both electrically connected to the first battery cluster, and the third interface and the fourth interface are both electrically connected to the second battery cluster.

6. The balancing device according to any one of claims 1 to 5, characterized in that: The balancing device further comprises a box, wherein the control unit and the balancing unit are both located in the box; The box body is provided with a terminal block, and the terminal block is electrically connected to the first battery cluster and the second battery cluster respectively.

7. The equalizing device according to claim 6, characterized in that: The box is provided with a first switch component, a second switch component and an auxiliary switch component, the balancing device includes a first main switch, a second main switch and an auxiliary switch, the first switch component is connected to the first main switch, the second switch component is connected to the second main switch, and the auxiliary switch component is connected to the auxiliary switch; The display is arranged on the surface of the box; The equalizing device comprises: a first interface, a second interface, a third interface and a fourth interface, wherein the first interface, the second interface, the third interface and the fourth interface are all located in the wiring terminal row; The box body is also provided with shutters; The box body is provided with a through hole for placing the heat dissipation unit, and the heat dissipation unit is located in the through hole.

8. A battery system, characterized in that: include: Multiple battery clusters; Wherein, each of the battery clusters is subjected to equalization processing by using the equalization device as described in any one of claims 1 to 7.

9. A balancing method, characterized in that: The equalization method is implemented by using the equalization device according to any one of claims 1 to 7, and comprises: When the balancing device is electrically connected to a first battery cluster to be balanced and a second battery cluster to be balanced respectively, a control unit acquires a first voltage of the first battery cluster and a second voltage of the second battery cluster; The control unit controls the connection relationship of each equalizing resistor at least according to the first voltage and the second voltage to adjust the resistance value of the equalizing unit; The balancing method further includes: when the auxiliary switch is closed, the auxiliary switch is connected to the first interface, the power processing unit is connected to the second interface, and the voltage of the first battery cluster is greater than the voltage of the second battery cluster, the power processing unit converts the voltage provided by the first battery cluster to obtain the power supply voltage of the control unit and supplies power to the control unit.

10. The equalization method according to claim 9, characterized in that: Before controlling the connection relationship of the balancing resistors, the method further includes: calculating a voltage difference between the first voltage and the second voltage; When the voltage difference is greater than a third preset value, it is determined that the first battery cluster and the second battery cluster need to be subjected to the balancing process.

11. The equalization method according to claim 9, characterized in that: Controlling the connection relationship of each balancing resistor at least according to the first voltage and the second voltage specifically includes: calculating a voltage difference between the first voltage and the second voltage; The connection relationship of each of the equalizing resistors is controlled at least according to the corresponding relationship between the voltage difference and the preset voltage interval.

12. The equalization method according to claim 11, characterized in that: At least according to the corresponding relationship between the voltage difference and the preset voltage range, controlling the connection relationship of each of the balancing resistors specifically includes: The connection relationship of each of the balancing resistors is controlled according to the corresponding relationship between the voltage difference and the preset voltage interval, and the temperature of the balancing unit.

13. The equalization method according to claim 12, characterized in that: According to the correspondence between the voltage difference and the preset voltage interval, and the temperature of the balancing unit, controlling the connection relationship of each balancing resistor specifically includes: When the temperature is lower than the first preset temperature and the voltage difference is higher than the third preset value and lower than the fourth preset value, controlling all the balancing resistors to be connected in parallel; When the temperature is lower than the first preset temperature and the voltage difference is greater than or equal to the fourth preset value and lower than the fifth preset value, or when the temperature is greater than or equal to the first preset temperature and lower than the second preset temperature and the voltage difference is greater than the third preset value and lower than the fourth preset value, the control part connects the balancing resistors in series; When the temperature is lower than the first preset temperature and the voltage difference is higher than the fifth preset value, or when the temperature is higher than or equal to the second preset temperature and lower than the third preset temperature and the voltage difference is higher than the third preset value and lower than the fifth preset value, controlling all the balancing resistors to be connected in series; When the temperature is greater than or equal to the third preset temperature, the first switch, the second switch and the third switch in the balancing unit are controlled to be disconnected, so as to control the balancing resistors to have no electrical connection.

14. The equalization method according to any one of claims 9 to 13, characterized in that: Also includes: When the temperature is greater than or equal to a fourth preset temperature and less than the third preset temperature, the control unit controls the heat dissipation unit to turn on; Wherein, the fourth preset temperature is lower than the first preset temperature.

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