CN110015130B

CN110015130B - Battery equalization system, vehicle, battery equalization method, and storage medium

Info

Publication number: CN110015130B
Application number: CN201710776103.0A
Authority: CN
Inventors: 罗红斌; 王超; 沈晓峰; 曾求勇
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2017-08-31
Filing date: 2017-08-31
Publication date: 2021-01-19
Anticipated expiration: 2037-08-31
Also published as: WO2019042353A1; CN110015130A

Abstract

The disclosure discloses a battery equalization system, a vehicle, a battery equalization method and a storage medium. The battery equalization system comprises an acquisition circuit, an equalization circuit and a controller; the controller is connected with an acquisition circuit and an equalizing circuit corresponding to the same single battery in the battery pack through a control channel, and the acquisition circuit and the equalizing circuit multiplex the control channel in a time-sharing manner; when the acquisition circuit needs to acquire the parameter information of the single batteries in the battery pack, the equalization circuit is in a conducting state; when the balancing circuit needs to balance the single batteries in the battery pack, the acquisition circuit is in a short-circuit state. The controller, the voltage sampling circuit and the equalizing circuit of each single battery in the disclosure multiplex a channel in a time-sharing manner, so that the requirement on the number of channels of the controller is reduced, and further, the hardware cost is reduced; and because the battery sampling and the equalization are carried out separately, the equalization current does not influence the battery voltage, thereby improving the accuracy of the battery voltage sampling.

Description

Battery equalization system, vehicle, battery equalization method, and storage medium

Technical Field

The present disclosure relates to the field of battery pack balancing, and in particular, to a battery balancing system, a vehicle, a battery balancing method, and a storage medium.

Background

In an electric vehicle, a battery pack is an important component thereof. Because the battery pack is formed by connecting a plurality of single batteries in series, along with the use of the batteries, the difference between the single batteries in the battery pack is gradually enlarged, and the consistency between the single batteries is poor. Due to the short plate effect of the battery, the capacity of the battery pack cannot be fully utilized, and the overall capacity of the battery pack is reduced. Therefore, the battery pack of the electric automobile is effectively and uniformly managed, the consistency of each single battery in the battery pack is favorably improved, the capacity loss of the battery is reduced, the service life of the battery is prolonged, and the driving range of the electric automobile is prolonged, so that the method has very important significance.

In the related art, a battery equalization system generally includes: the battery management system comprises a battery management controller and a plurality of battery information collectors, wherein each battery information collector comprises a control unit, a battery sampling circuit, a battery equalization circuit and other three modules, and the battery sampling circuit and the battery equalization circuit are respectively applied to different channels. Each single battery of the battery pack is provided with a battery detection circuit channel and a battery equalization circuit channel. The working process comprises the following steps: the battery sampling circuit is responsible for sampling battery voltage information in real time, the control unit of the battery information collector sends the battery sampling information to the battery management controller, the battery management controller judges whether the balance needs to be started or not, then a balance instruction is sent to the control unit of the battery information collector, and the control unit of the battery information collector controls the battery balance circuit to start balance.

In the practical application of the related equalization technology, because a control channel is needed between the control unit and the voltage sampling circuit and the equalization circuit of each single battery, the requirement for the number of channels of the controller is increased, and the hardware cost is higher; and because the battery sampling and the equalization are carried out simultaneously, the equalization current can influence the battery voltage, thereby influencing the accuracy of the battery voltage sampling.

Disclosure of Invention

The present disclosure is directed to a battery equalization system, a vehicle, a battery equalization method, and a storage medium, which are used to solve the technical problem of high hardware cost of the battery equalization system in the related art.

In order to achieve the above object, the present disclosure provides a battery equalization system, including an acquisition circuit, an equalization circuit, and a controller; the controller is connected with an acquisition circuit and an equalizing circuit corresponding to the same single battery in the battery pack through a control channel, and the acquisition circuit and the equalizing circuit multiplex the control channel in a time-sharing manner;

the acquisition circuit is used for acquiring parameter information of the single batteries in the battery pack; when the acquisition circuit needs to acquire parameter information of the single batteries in the battery pack, the equalization circuit is in a conducting state;

the equalizing circuit is used for equalizing the single batteries in the battery pack; when the balancing circuit needs to balance the single batteries in the battery pack, the acquisition circuit is in a short-circuit state; and

the controller is used for controlling the balancing circuit to perform balancing processing on the single batteries needing to be balanced when the single batteries in the battery pack are determined to need to be balanced according to the parameter information of the battery pack.

Optionally, the equalizing circuit is connected to the corresponding single battery through a first equalizing branch and a second equalizing branch, and one end of each of the first equalizing branch and the second equalizing branch is connected to two poles of the corresponding single battery; the other ends of the first equalizing branch and the second equalizing branch are connected between the acquisition circuit and the equalizing circuit;

when the acquisition circuit needs to acquire parameter information of the single batteries in the battery pack, the first equalization branch is disconnected and the second equalization branch is connected;

when the balancing circuit needs to balance the single batteries in the battery pack, the first balancing branch and the second balancing branch corresponding to the single batteries are conducted.

Optionally, the second equalizing branch maintains a conducting state, and a first switch is disposed on the first equalizing branch; when the acquisition circuit needs to acquire parameter information of the single batteries in the battery pack, the first switch is switched off; when the balancing circuit performs balancing processing on the single battery needing to be started for balancing, a first switch on a first balancing branch corresponding to the single battery is closed.

Optionally, the controller is further configured to control the balancing circuit to balance the single battery needing balancing according to a target balancing duration of the single battery needing balancing and obtained from the parameter information of the battery pack and a balancing duty ratio, where the balancing duty ratio is a ratio of a duration that the balancing circuit occupies the control channel to a total duration that the control channel is occupied.

Optionally, the controller is further configured to determine an equalization time period and an acquisition time period according to the target equalization time period and the equalization duty cycle, where a sum of the equalization time period and the acquisition time period is equal to a total occupied time period of the control channel; in the balancing time period, the control channel is communicated with the balancing circuit so that the balancing circuit performs balancing processing on the single batteries in the battery pack; and in the acquisition time period, the control channel is communicated with the acquisition circuit so that the acquisition circuit acquires the parameter information of the battery pack.

Optionally, the controller is configured to obtain a target equalization duration of the cell requiring start equalization by:

determining whether a single battery in the battery pack needs to be balanced or not according to the parameter information of the battery pack acquired by the acquisition circuit;

and when determining that the single battery in the battery pack needs to be balanced, calculating the target balancing time length of the single battery needing to be balanced according to the parameter information of the battery pack.

Optionally, when the single battery in the battery pack does not need to be equalized, the acquisition circuit of the single battery is connected to the controller through the corresponding control channel.

Optionally, the controller is further configured to control the equalizing circuit to discharge the single batteries when a difference between the voltage of the single batteries and the minimum voltage of each single battery is greater than a preset voltage difference threshold.

Optionally, the controller is further configured to control the equalizing circuit to charge the single batteries when a difference between the voltage of the single batteries and the maximum voltage of each single battery is greater than a preset voltage difference threshold.

Optionally, the controller includes a control chip, the control chip is connected to the acquisition module and the equalization module corresponding to the same battery cell through a pin, and the pin is connected to the equalization circuit and the acquisition circuit through the control channel.

Optionally, the balancing circuit comprises a balancing resistor connected in parallel with the single battery.

The present disclosure also provides a vehicle including the above battery equalization system.

The present disclosure also provides a battery equalization method, which is applied to a battery equalization system, wherein the battery equalization system comprises a controller, an acquisition circuit and an equalization circuit; the controller is connected with an acquisition circuit and an equalizing circuit corresponding to the same single battery in the battery pack through a control channel, and the acquisition circuit and the equalizing circuit multiplex the control channel in a time-sharing manner;

the method comprises the following steps:

communicating the control channel with the acquisition circuit and controlling the equalization circuit to be in a conducting state;

acquiring parameter information of a single battery in the battery pack through the acquisition circuit;

determining that a single battery in the battery pack needs to be started for balancing according to the parameter information of the battery pack through the controller;

communicating the control channel with an equalization circuit corresponding to the single battery needing to be balanced and controlling the acquisition circuit to be in a short circuit state;

and controlling the balancing circuit to perform balancing processing on the single batteries needing to be balanced by the controller.

the controlling the equalization circuit to be in a conducting state includes:

disconnecting the first equalization branch and connecting the second equalization branch;

the control the acquisition circuit is in a short circuit state, including:

and conducting a first equalizing branch and a second equalizing branch corresponding to the single battery.

Optionally, the determining, by the controller, that there is a single battery in the battery pack that needs to start balancing according to the parameter information of the battery pack includes:

determining, by the controller, the single battery to be started for balancing, a target balancing duration of the single battery to be started for balancing, and a balancing duty ratio according to parameter information of the battery pack, where the balancing duty ratio is a ratio of a duration in which the balancing circuit occupies the control channel to a total duration in which the control channel is occupied;

the controlling the balancing circuit to perform balancing processing on the single battery needing to be balanced by the controller includes:

and controlling the balancing circuit to perform balancing processing on the single battery needing to be started and balanced by the controller according to the target balancing duration of the single battery needing to be started and balanced and the balancing duty ratio.

Optionally, the method further comprises:

determining a balance time period and an acquisition time period according to the target balance time length and the balance duty ratio, wherein the sum of the balance time period and the acquisition time period is equal to the total occupied time length of the control channel;

the will control the passageway intercommunication acquisition circuit includes:

in the acquisition time period, communicating the control channel with the acquisition circuit;

the equalizing circuit which connects the control channel to the single battery needing to be equalized comprises:

and in the balancing time period, the control channel is communicated with the balancing circuit corresponding to the single battery needing to be balanced.

Optionally, the determining, according to the parameter information of the battery pack, the target equalization duration of the single battery that needs to be equalized includes:

determining whether a single battery in the battery pack needs to be started for balancing or not according to the acquired parameter information of the battery pack;

and when determining that the single batteries in the battery pack need to be started for balancing, calculating the target balancing time length of the single batteries needing to be started for balancing.

Optionally, when the single battery in the battery pack does not need to be equalized, the method further includes:

and connecting the acquisition circuit of the single battery with the controller through the corresponding control channel.

Optionally, the controlling, by the controller, the balancing circuit to perform balancing processing on the single battery requiring balancing to be started includes:

and controlling the balancing circuit to carry out balanced discharge on the single batteries needing to be started for balancing through the controller.

and controlling the equalizing circuit to perform equalizing charge on the single batteries needing to be subjected to equalizing charge through the controller.

The present disclosure also provides a computer readable storage medium having stored thereon computer program instructions which, when executed by a processor, implement the battery equalization method described above.

The technical scheme provided by the embodiment of the disclosure can have the following beneficial effects:

the controller, the voltage sampling circuit and the equalizing circuit of each single battery in the disclosure multiplex a channel in a time-sharing manner, so that the requirement on the number of the channels of the controller is reduced, and further, the hardware cost is reduced; and because the battery sampling and the equalization are carried out separately, the equalization current does not influence the battery voltage, thereby improving the accuracy of the battery voltage sampling.

Additional features and advantages of the disclosure will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description serve to explain the disclosure without limiting the disclosure. In the drawings:

fig. 1 is a block diagram illustrating a battery equalization system according to an exemplary embodiment.

Fig. 2 is a schematic diagram of an equalization circuit of a battery equalization system according to an exemplary embodiment.

Fig. 3 is another block diagram illustrating a battery equalization system in accordance with an exemplary embodiment.

Fig. 4 is a flow chart illustrating a method of battery equalization in accordance with an exemplary embodiment.

Fig. 5 is another flow chart illustrating a method of battery equalization in accordance with an exemplary embodiment.

Fig. 6 is a flowchart illustrating a battery balancing method according to an exemplary embodiment, which includes steps of determining a cell requiring balancing to be turned on and a target balancing duration thereof.

Fig. 7 is another flow chart illustrating a method of battery equalization in accordance with an exemplary embodiment.

Fig. 8 is another flow chart illustrating a method of battery equalization in accordance with an exemplary embodiment.

Detailed Description

The following detailed description of specific embodiments of the present disclosure is provided in connection with the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present disclosure, are given by way of illustration and explanation only, not limitation.

Fig. 1 is a block diagram illustrating a battery equalization system according to an exemplary embodiment. As shown in fig. 1, the battery balancing system includes an acquisition circuit 12, a balancing circuit 13, and a controller 14, wherein the battery pack 11 is formed by connecting a plurality of single batteries 111 in series.

In fig. 1, the controller 14 is connected to the acquisition circuit 12 and the equalization circuit 13 corresponding to the same single battery 111 through a control channel 140, and the acquisition circuit 12 and the equalization circuit 13 multiplex the control channel 140 in time division. The controller 14 includes a control chip, the control chip is connected to the acquisition circuit 12 and the equalization circuit 13 corresponding to the same battery cell 111 through a pin, and the pin is connected to the equalization circuit 13 and the acquisition circuit 12 through the control channel 140.

The acquisition circuit 12 and the equalization circuit 13 corresponding to the same single battery 111 share one control channel 140 of the controller 14, so that the number of required channels of the controller 14 is reduced, and the requirement on the number of channels of the controller 14 is further reduced.

For example, when the existing acquisition circuit and the existing equalization circuit are connected to the controller through one control channel, 2N control channels correspond to N single cells. The acquisition circuit and the equalizing circuit of the same single battery share one control channel to be connected with the controller, and the N single batteries correspond to the N control channels, so that the number of the control channels can be reduced, and the cost of the controller is reduced.

When the existing acquisition circuit and the existing equalization circuit are respectively connected with the controller through one control channel, the N single batteries correspond to the 2N control channels, and the 2N control channels need to be controlled. The acquisition circuit and the equalization circuit of the same single battery share one control channel of the controller, so that the N single batteries correspond to the N control channels, and only the N control channels need to be controlled, so that the control flow can be simplified, and the misoperation rate of the controller is reduced.

When the existing acquisition circuit and the existing equalization circuit are respectively connected with the controller through one control channel, the N single batteries correspond to the 2N control channels, and the qualification rate of connecting the controller through the control channels is determined by the qualification rate of the 2N control channels. This open collection circuit and equalizer circuit of same battery cell share controller's a control channel, and a N battery cell corresponds a N control channel, and the qualification rate of switching on the controller through the control channel is decided by the qualification rate of a N control channel, can improve the total qualification rate that a plurality of battery cells switched on the controller through the control channel among the entire system like this, and then improve battery equalizing system's qualification rate.

As shown in fig. 1, the acquisition circuit 12 is configured to acquire parameter information of the single batteries 111 in the battery pack 11 and send the acquired parameter information of the battery pack to the controller 14, where the single batteries 111 in the battery pack 11 correspond to the acquisition circuit 12 one to one. The parameter information comprises information such as battery voltage and temperature. The controller 14 communicates the control channel 140 with the acquisition circuit 12, so as to control the acquisition circuit 12 to acquire parameter information of the battery pack 11. When the controller 14 controls the acquisition circuit 12 to acquire parameter information of the single cells 111 in the battery pack 11, the equalization circuit 13 is in a conducting state. When the acquisition circuit 12 acquires the parameter information of the battery pack 11, the equalizing circuit 13 being in the on state does not mean that the equalizing circuit 13 performs equalizing processing on the single battery, but means that when the acquisition circuit 12 is communicated with the single battery 111, the equalizing circuit 13 corresponding to the single battery 111 corresponds to a part of the acquisition circuit 12.

For example, referring to fig. 2, the equalizing circuit 13 may include an equalizing resistor 130 connected in parallel to the single battery 111. As shown in fig. 2 and fig. 3, fig. 3 is another block diagram of a battery equalization system according to an exemplary embodiment, when the controller 14 controls the acquisition circuit 12 to acquire parameter information of the single batteries 111 in the battery pack 11, a branch in which the acquisition circuit 12 is located is in a conducting state, the second equalization branch 132 in which the equalization circuit 13 is located may also be in a conducting state, and the first equalization branch 131 is in a disconnecting state. At this time, the acquisition circuit 12 and the balancing resistor 130 are connected in series in a branch, and both ends of the branch are respectively connected to two stages of the single battery 111, that is, when the acquisition circuit 12 is communicated with the single battery 111, the balancing resistor 130 included in the balancing circuit 13 may be a part of the acquisition circuit 12.

As shown in fig. 1, the equalizing circuit 13 is connected to the corresponding single battery 111 through a first equalizing branch 131 and a second equalizing branch 132, one end of the second equalizing branch 132 and one end of the first equalizing branch 131 are connected to two poles of the single battery 111, and the other end of the first equalizing branch 131 and the other end of the second equalizing branch 132 are connected between the acquiring circuit 12 and the equalizing circuit 13. In fig. 1, the first equalizing branch 131 is connected to the positive electrode of the single battery 111, and the second equalizing branch 132 is connected to the negative electrode of the single battery 111.

As shown in fig. 1, when the acquisition circuit 12 needs to acquire parameter information of the single batteries in the battery pack, the controller 14 may control the first equalizing branch 131 to be turned off, and control the second equalizing branch 132 where the equalizing circuit 13 is located and the branch where the acquisition circuit 12 is located to be turned on, and at this time, the equalizing circuit 13 and the branch where the acquisition circuit 12 is located may be in a conducting state together.

As shown in fig. 1, the equalizing circuit 13 is configured to perform an equalizing process on the single batteries 111 in the battery pack 11, and the single batteries 111 in the battery pack 11 correspond to the equalizing circuit 13 one by one. When the battery pack 11 has the single battery 111 requiring equalization, the controller 14 connects the control channel 140 to the equalization circuit 13, and then controls the equalization circuit 13 to perform equalization processing on the single battery 111 requiring equalization. When the equalizing circuit 13 performs equalizing processing on the single batteries 111 in the battery pack 11, the controller 14 may control the first equalizing branch 131 and the second equalizing branch 132 to be conducted, so that the equalizing circuit 13 is in a conducting state, and the collecting circuit 12 is in a short-circuit state.

Optionally, when the single battery 111 in the battery pack 11 does not need to be equalized, the acquisition circuit 12 corresponding to the single battery 111 is connected to the controller 14 through the corresponding control channel 140. That is, when the controller 14 determines that the single battery 111 is balanced, the controller 14 disconnects the balancing circuit 13 corresponding to the single battery 111 from the control channel 140, and controls the acquisition circuit 12 corresponding to the single battery 111 to communicate with the control channel 140.

As shown in fig. 1, the controller 14 is connected to the acquisition circuit 12 and the equalization circuit 13. When the control channel 140 is connected to the collecting circuit 12, the controller 14 is configured to receive parameter information of the battery pack 11. When the controller 14 determines that there is a single battery 111 requiring equalization in the plurality of single batteries 111 according to the parameter information of the battery pack 11, the controller 14 connects the control channel 140 to the equalization circuit 13, so that the equalization circuit 13 performs equalization processing on the single battery 111.

The equalization circuit 13 may adopt an equalization processing manner of discharging the single battery 111 requiring equalization, for example, in fig. 2 and 3, two ends of the single battery 111 requiring equalization are connected in parallel with an equalization resistor 130. The equalizing circuit 13 may also adopt an equalizing processing method of charging the single battery 111 requiring equalization, for example, the single battery 111 requiring equalization is connected to a generator or a storage battery of a vehicle, and the single battery 111 requiring equalization is charged by the generator or the storage battery.

Optionally, the controller 14 may further control the equalizing circuit 13 to perform equalization processing on the single battery 111 requiring equalization starting according to the target equalization duration of the single battery 111 requiring equalization starting determined by the parameter information of the battery pack 11. The controller 14 may obtain the target equalization duration of the single battery 111 requiring the start of equalization by: determining whether a single battery 111 in the battery pack 11 needs to be started for balancing according to the parameter information of the battery pack 11 acquired by the acquisition circuit 12; when determining that the single battery 111 in the battery pack 11 needs to start the equalization, calculating the target equalization duration of the single battery 111 needing to start the equalization according to the parameter information of the battery pack 11.

As shown in fig. 1, when the battery balancing system performs balancing processing on a single battery by using a passive balancing method, that is, discharges the single battery 111 requiring balancing activation, the controller 14 may determine the single battery 111 requiring balancing activation by:

firstly, according to the voltage values of the single batteries 111 in the battery pack 11 acquired by the acquisition circuit 12, the minimum voltage value in the voltage values of the single batteries 111 in the battery pack 11 is taken as a reference voltage value;

then, according to a voltage difference between the voltage value of each single battery 111 in the battery pack 11 and the reference voltage value, the single battery 111 whose voltage difference is greater than or equal to a preset voltage difference threshold is determined as the single battery 111 requiring starting equalization.

Of course, in other embodiments, the single battery requiring starting of equalization may be determined according to other parameter information of the battery pack, for example, when the battery equalization system performs equalization processing on the single battery in an active equalization manner, that is, when the single battery requiring starting of equalization is charged, a maximum voltage value among voltage values of the single batteries in the battery pack is used as a reference voltage value.

For example, the minimum voltage value among the voltage values of the single batteries 111 of the battery pack 11 may be used as the reference voltage value, and the preset voltage difference threshold may be 5mV (or other values). Firstly, the controller 14 connects the control channel 140 to the acquisition circuit 12, and further controls the acquisition circuit 12 to acquire the voltage value of each single battery 111 of the battery pack 11; at the same time, the controller 14 controls the first equalizing branch 131 to be opened.

Next, the controller 14 compares the minimum voltage value Vmin of the single batteries 111 to determine whether the difference between the voltage value of each single battery 111 of the battery pack 11 and the Vmin is less than 5 mV. If yes, the battery pack 11 has good balance consistency and does not need to be balanced; if the difference value is more than 5mV, the single battery 111 with the difference value of more than 5mV with Vmin is taken as the single battery 111 needing to start the equalization.

Then, after determining the single battery 111 requiring balancing to be turned on, the target balancing duration of the single battery 111 requiring balancing to be turned on may be calculated according to the voltage value and Vmin of the single battery 111 requiring balancing to be turned on, and then the controller 14 connects the control channel 140 to the balancing circuit 13, at the same time, the controller 14 may control the first balancing branch 131 and the second balancing branch 132 to be conducted, and then the controller 14 controls the balancing circuit 13 to discharge the single battery 111 requiring balancing to be turned on according to the target balancing duration of the single battery 111 requiring balancing to be turned on.

Then, after the discharge starts, the controller 14 counts the discharge time of the balancing circuit 13 for the single battery 111 requiring the balancing, and stops the discharge when the difference between the discharge time of the single battery 111 and the target balancing time is within the threshold range, and the balancing is finished. The controller 14 disconnects the equalizing circuit 13 corresponding to the single battery 111 from the control channel 140, and controls the collecting circuit 12 corresponding to the single battery 111 to communicate with the control channel 140.

Referring to fig. 1, the second equalizing branch 132 may be kept in a conducting state all the time, and the first equalizing branch 131 is provided with a first switch K1. The first switch K1 is controlled by the controller 14. Alternatively, the first switch K1 may be a relay switch, and the controller 14 outputs a control signal to control the first switch K1 to be in an open state or a closed state.

When the acquisition circuit 12 needs to acquire parameter information of the single battery 111 in the battery pack 11, the controller 14 controls the first switch K1 to be turned off. When the balancing circuit 13 performs balancing processing on the single battery 111 requiring balancing, the controller 14 controls the first switch K1 on the first balancing branch 131 corresponding to the single battery 111 to be closed.

Optionally, as shown in fig. 1, the controller 14 may further control the equalizing circuit 13 to perform equalization processing on the single battery 111 requiring equalization according to the target equalization duration and an equalization duty cycle, where the equalization duty cycle is a ratio of a duration that the equalizing circuit 13 occupies the control channel 140 to a total duration that the control channel 140 is occupied; wherein, the total duration of the control channel 140 occupied includes the duration of the equalizing circuit 13 occupying the control channel 140 and the duration of the collecting circuit 12 occupying the control channel 140.

As shown in fig. 1, first, the controller 14 connects the control channel 140 to the acquisition circuit 12, so as to control the acquisition circuit 12 to acquire parameter information of the battery pack 11; at the same time, the controller 14 controls the first switch K1 to be opened.

Then, when determining that the single battery 111 in the battery pack 11 needs to start equalization according to the parameter information of the single battery 111 in the battery pack 11, the controller 14 obtains a target equalization duration and an equalization duty ratio of the single battery 111 needing to start equalization, and connects the control channel 140 to the equalization circuit 13 corresponding to the single battery 111 needing to start equalization; at the same time, the controller 14 may control the first switch K1 to close.

Then, the controller 14 controls the balancing circuit 13 to perform balancing processing on the single battery 111 requiring balancing according to the target balancing duration and the balancing duty ratio of the single battery 111 requiring balancing.

Optionally, the controller 14 determines an equalization time period and an acquisition time period according to the target equalization time period and the equalization duty ratio, and a sum of the equalization time period and the acquisition time period is equal to a total occupied time period of the control channel 140; in the collection time period, the controller 14 controls the control channel 140 to connect with the collection circuit 12, so that the collection circuit 12 collects the parameter information of the battery pack 11, and at the same time, the controller 14 controls the first switch K1 to be switched off; in the balancing time period, the controller 14 controls the control channel 140 to communicate with the balancing circuit 13 that needs to be balanced, and the controller 14 may control the first switch K1 to be closed, so that the balancing circuit 13 performs balancing on the single battery 111 that needs to be balanced in the battery pack 11.

According to the battery pack parameter information acquisition device, the first switch is arranged on the first equalization branch, when the parameter information of the battery pack needs to be acquired, the control channel is connected to the acquisition circuit, and the first switch is disconnected; when the balance is needed, the control channel is connected to the balance circuit, the first switch is closed, one control channel is multiplexed in a time-sharing mode, the requirement for the number of channels of the controller is reduced, and therefore hardware cost is reduced; and because the battery sampling and the equalization are carried out separately, the equalization current does not influence the battery voltage, thereby improving the accuracy of the battery voltage sampling.

Optionally, a control switch may be disposed on the control channel 140. When the acquisition circuit 12 is required to acquire parameter information of the battery pack 11, that is, in the acquisition time period, the controller 14 controls the control switch to be connected to the acquisition circuit 12, so that the control channel 140 is communicated with the acquisition circuit 12. When the equalizing circuit 13 is required to perform equalizing processing on the single batteries 111 in the battery pack 11, that is, during the equalizing time period, the controller 14 controls the control switch to be connected to the equalizing circuit 13, so that the control channel 140 is communicated with the equalizing circuit 13.

This is disclosed through setting up control switch between controller and acquisition circuit, equalizer circuit, the controller can reach the effect of gathering and equalizing through the state of adjusting control switch to not sampling when can realizing the equilibrium, unbalanced effect during the sampling, thereby equalizing current can not influence battery voltage, thereby precision when having improved battery voltage sampling.

When the existing acquisition circuit and the existing equalization circuit are respectively connected with a controller through a control channel, each single battery corresponds to two control channels, each control channel corresponds to one pin of a control chip, namely, N single batteries correspond to 2N pins. And this collection circuit and equalizer circuit of same battery cell of this disclosure share a control channel and be connected with the controller, and a control channel corresponds a pin, and N battery cell corresponds N control channel promptly, corresponds N pin, can reduce the demand of control chip pin like this, on prior art's basis, can reduce half pin quantity, effectively reduced the control chip cost.

Optionally, the controller includes a first control unit disposed in the battery information collector, and a second control unit disposed in the battery management controller. Optionally, the acquisition circuit sends acquired parameter information of the single battery in the battery pack to the second control unit through the first control unit; the acquisition circuit and the equalization circuit of the same single battery correspond to one connecting channel of the first control unit.

The first control unit can be connected to the acquisition circuit by controlling the connecting channel, and then the acquisition circuit is controlled to acquire parameter information of the single batteries in the battery pack. The second control unit can also send an acquisition instruction to the first control unit through the communication unit so as to control the connection channel to be connected to the acquisition circuit through the first control unit.

The first control unit can be connected to the equalizing circuit by controlling the connecting channel, and further controls the equalizing circuit to perform equalizing processing on the single batteries needing to be equalized. The first control unit can send the parameter information of the battery pack acquired by the acquisition circuit to the second control unit, the second control unit determines the single battery needing to be balanced according to the parameter information of the battery pack, and sends a balancing instruction to the first control unit through the communication unit so as to control the connection channel to be connected to the balancing circuit through the first control unit.

When the acquisition circuit in the battery equalization system sends acquired parameter information of the single batteries in the battery pack to the second control unit through the first control unit, the acquisition circuit and the equalization circuit of the same single battery correspond to one connection channel of the first control unit, and the number of channels required by the first control unit is reduced.

The first control unit of the battery information collector and the second control unit of the battery management controller can selectively perform balance control on the single batteries needing to be balanced. That is, the first control unit may control the balancing circuit to perform balancing processing on the single battery to be balanced, and the second control unit may control the balancing circuit to perform balancing processing on the single battery to be balanced. The first control unit or the second control unit determines the single batteries needing to be balanced according to the parameter information of the battery pack acquired by the acquisition circuit.

When the battery information collector does not receive the balancing instruction sent by the battery management controller within the preset time, the first control unit receives the parameter information of the battery pack and controls the balancing circuit to balance the single batteries needing to be started when determining that the single batteries in the battery pack need to be started according to the parameter information of the battery pack.

When the battery information collector receives an instruction for indicating the battery information collector to perform equalization processing, the first control unit receives parameter information of the battery pack and controls the equalization circuit to perform equalization processing on the single batteries needing to be started when determining that the single batteries in the battery pack need to be started for equalization according to the parameter information of the battery pack.

When the battery information collector receives a fault message of the battery management controller, the first control unit receives parameter information of the battery pack and controls the balancing circuit to balance the single batteries needing to be balanced when the single batteries in the battery pack need to be balanced according to the parameter information of the battery pack.

The battery information collector and the battery management controller can selectively control the balancing system through the first control unit and the second control unit respectively, so that the normal operation of the battery balancing system can still be ensured under the condition that one of the battery information collector and the battery management controller fails or has faults.

With regard to the vehicle in the above-described embodiment, the battery equalization system included in the vehicle is described in detail in the above-described embodiment of the battery equalization system, and will not be explained in detail here.

Fig. 4 is a flow chart illustrating a method of battery equalization in accordance with an exemplary embodiment. As shown in fig. 4, the battery equalization method is applied to a battery equalization system, and the battery equalization system includes a controller, an acquisition circuit, and an equalization circuit; the controller is connected with an acquisition circuit and an equalizing circuit corresponding to the same single battery in the battery pack through a control channel, and the acquisition circuit and the equalizing circuit multiplex the control channel in a time-sharing manner; the method comprises the following steps.

And step S21, communicating the control channel with the acquisition circuit, and controlling the equalization circuit to be in a conducting state.

And step S22, acquiring parameter information of the single batteries in the battery pack through the acquisition circuit.

And step S23, determining that a single battery in the battery pack needs to be balanced according to the parameter information of the battery pack through the controller.

And step S24, communicating the control channel with the equalization circuit corresponding to the single battery needing to be balanced and controlling the acquisition circuit to be in a short circuit state.

And step S25, controlling the balancing circuit to perform balancing processing on the single battery needing to be balanced by the controller.

Fig. 5 is another flow chart illustrating a method of battery equalization in accordance with an exemplary embodiment. As shown in fig. 5, the equalizing circuits are respectively connected to the corresponding single batteries through a first equalizing branch and a second equalizing branch, and one ends of the first equalizing branch and the second equalizing branch are respectively connected to two poles of the single battery; the other ends of the first equalizing branch and the second equalizing branch are connected between the acquisition circuit and the equalizing circuit; the method comprises the following steps.

And step S31, connecting the control channel to the acquisition circuit, disconnecting the first equalization branch and connecting the second equalization branch.

And step S32, acquiring parameter information of the single batteries in the battery pack through the acquisition circuit.

Step S33, determining the single battery needing to be started for balancing, the target balancing time length of the single battery needing to be started for balancing and the balancing duty ratio according to the parameter information of the battery pack through the controller, wherein the balancing duty ratio is the ratio of the time length of the balancing circuit occupying the control channel to the total time length of the control channel occupied.

And step S34, communicating the control channel with the equalization circuit corresponding to the single battery needing to be equalized, and conducting a first equalization branch and a second equalization branch corresponding to the single battery.

And step S35, controlling the balancing circuit to perform balancing processing on the single battery needing to be started and balanced by the controller according to the target balancing duration of the single battery needing to be started and balanced and the balancing duty ratio.

Optionally, as shown in fig. 6, the determining, according to the parameter information of the battery pack, the target equalization duration of the single battery that needs to be equalized includes:

step S331, determining whether a single battery in the battery pack needs to be balanced or not according to the acquired parameter information of the battery pack through the controller;

step S332, when it is determined that a single battery in the battery pack needs to start balancing, calculating the target balancing time length of the single battery needing to start balancing according to the parameter information of the battery pack through the controller.

Optionally, the method further comprises: determining, by the controller, a balance time period and an acquisition time period according to the target balance time length and the balance duty ratio, wherein the sum of the balance time period and the acquisition time period is equal to the total occupied time length of the control channel;

wherein, with the control channel intercommunication acquisition circuit includes: in the acquisition time period, communicating the control channel with the acquisition circuit;

the equalizing circuit which connects the control channel to the single battery needing to be equalized comprises: and in the balancing time period, the control channel is communicated with the balancing circuit corresponding to the single battery needing to be balanced.

Fig. 7 is another flow chart illustrating a method of battery equalization in accordance with an exemplary embodiment. As shown in fig. 7, the method includes the following steps.

And step S51, connecting the control channel with the acquisition circuit, disconnecting the first equalization branch and connecting the second equalization branch.

And step S52, acquiring parameter information of the single batteries in the battery pack through the acquisition circuit.

And step S53, determining that a single battery in the battery pack needs to be balanced according to the parameter information of the battery pack through the controller.

And step S54, communicating the control channel with the equalization circuit corresponding to the single battery needing to be equalized, and conducting a first equalization branch and a second equalization branch corresponding to the single battery.

And step S55, controlling the balancing circuit to discharge the single battery needing to be balanced by the controller.

And step S56, when the single battery in the battery pack does not need to be equalized, connecting the acquisition circuit of the single battery with the controller through the corresponding control channel.

Fig. 8 is another flow chart illustrating a method of battery equalization in accordance with an exemplary embodiment. As shown in fig. 8, the method includes the following steps.

And step S61, connecting the control channel with the acquisition circuit, disconnecting the first equalization branch and connecting the second equalization branch.

And step S62, acquiring parameter information of the single batteries in the battery pack through the acquisition circuit.

And step S63, determining that a single battery in the battery pack needs to be balanced according to the parameter information of the battery pack through the controller.

And step S64, communicating the control channel with the equalization circuit corresponding to the single battery needing to be equalized, and conducting a first equalization branch and a second equalization branch corresponding to the single battery.

And step S65, controlling the balancing circuit to charge the single battery needing to be balanced by the controller.

And step S66, when the single battery in the battery pack does not need to be equalized, connecting the acquisition circuit of the single battery with the controller through the corresponding control channel.

With regard to the battery equalization method in the above embodiment, the specific manner of each step has been described in detail in the embodiment related to the battery equalization system, and will not be elaborated here.

The preferred embodiments of the present disclosure are described in detail with reference to the accompanying drawings, however, the present disclosure is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present disclosure within the technical idea of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

It should be noted that the various features described in the above embodiments may be combined in any suitable manner without departing from the scope of the invention. In order to avoid unnecessary repetition, various possible combinations will not be separately described in this disclosure.

In addition, any combination of various embodiments of the present disclosure may be made, and the same should be considered as the disclosure of the present disclosure, as long as it does not depart from the spirit of the present disclosure.

Claims

1. A battery equalization system is characterized by comprising an acquisition circuit, an equalization circuit and a controller; the controller is connected with an acquisition circuit and an equalizing circuit corresponding to the same single battery in the battery pack through a control channel, and the acquisition circuit and the equalizing circuit multiplex the control channel in a time-sharing manner;

the controller is used for controlling the balancing circuit to perform balancing processing on the single batteries needing to be balanced when the single batteries in the battery pack are determined to need to be balanced according to the parameter information of the battery pack,

the equalizing circuit is connected to corresponding single batteries through a first equalizing branch and a second equalizing branch respectively, and one ends of the first equalizing branch and the second equalizing branch are connected to two poles of the single batteries respectively; the other ends of the first equalizing branch and the second equalizing branch are connected between the acquisition circuit and the equalizing circuit;

2. The battery equalization system of claim 1, wherein the second equalization branch is kept in a conducting state, and the first equalization branch is provided with a first switch; when the acquisition circuit needs to acquire parameter information of the single batteries in the battery pack, the first switch is switched off; when the balancing circuit performs balancing processing on the single battery needing to be started for balancing, a first switch on a first balancing branch corresponding to the single battery is closed.

3. The battery balancing system according to claim 1, wherein the controller is further configured to control the balancing circuit to balance the single battery cell requiring balancing according to a target balancing duration of the single battery cell requiring balancing and a balancing duty ratio, which are obtained from parameter information of the battery pack, where the balancing duty ratio is a ratio of a duration in which the balancing circuit occupies the control channel to a total duration in which the control channel is occupied.

4. The battery equalization system of claim 3, wherein the controller is further configured to determine an equalization time period and a collection time period according to the target equalization duration and the equalization duty cycle, and a sum of the equalization time period and the collection time period is equal to a total duration of the occupied control channel; in the balancing time period, the control channel is communicated with the balancing circuit so that the balancing circuit performs balancing processing on the single batteries in the battery pack; and in the acquisition time period, the control channel is communicated with the acquisition circuit so that the acquisition circuit acquires the parameter information of the battery pack.

5. The battery equalization system of claim 3, wherein the controller is configured to obtain the target equalization duration of the single battery cell requiring equalization to be started by:

6. The battery equalization system of claim 1, wherein when the single battery in the battery pack does not need equalization processing, the acquisition circuit of the single battery is connected with the controller through the corresponding control channel.

7. The battery equalization system of claim 1, wherein the controller is further configured to control the equalization circuit to discharge the single battery when a difference between a voltage of the single battery and a minimum voltage in each single battery is greater than a preset voltage difference threshold.

8. The battery equalization system of claim 1, wherein the controller is further configured to control the equalization circuit to charge the single batteries when a difference between the voltages of the single batteries and a maximum voltage in each single battery is greater than a preset voltage difference threshold.

9. The battery equalization system of claim 1, wherein the controller comprises a control chip, the control chip is connected to the acquisition circuit and the equalization circuit corresponding to the same cell through a pin, and the pin is connected to the equalization circuit and the acquisition circuit through the control channel.

10. The battery equalization system of claim 1, wherein the equalization circuit comprises an equalization resistor in parallel with the cells.

11. A vehicle comprising the battery equalization system of any of claims 1-10.

12. A battery equalization method is applied to a battery equalization system and is characterized in that the battery equalization system comprises a controller, an acquisition circuit and an equalization circuit; the controller is connected with an acquisition circuit and an equalizing circuit corresponding to the same single battery in the battery pack through a control channel, and the acquisition circuit and the equalizing circuit multiplex the control channel in a time-sharing manner;

the method comprises the following steps:

the controller controls the balancing circuit to perform balancing processing on the single batteries needing to be balanced,

the controlling the equalization circuit to be in a conducting state includes:

the control the acquisition circuit is in a short circuit state, including:

13. The method of claim 12, wherein the determining, by the controller, that there are single cells in the battery pack that need to start balancing according to the parameter information of the battery pack comprises:

14. The method of claim 13, further comprising:

15. The method according to claim 13, wherein the determining the target equalization duration of the single battery needing to be equalized according to the parameter information of the battery pack comprises:

16. The method of claim 12, wherein when the cells in the battery pack do not require equalization, the method further comprises:

17. The method according to claim 12, wherein the controlling, by the controller, the balancing circuit to perform balancing processing on the single battery needing balancing to be started comprises:

18. The method according to claim 12, wherein the controlling, by the controller, the balancing circuit to perform balancing processing on the single battery needing balancing to be started comprises:

19. A computer-readable storage medium having stored thereon computer program instructions, which, when executed by a processor, implement the battery equalization method of any of claims 12-18.