CN111181224A - Charging system for multi-section series battery pack and charging method thereof - Google Patents

Charging system for multi-section series battery pack and charging method thereof Download PDF

Info

Publication number
CN111181224A
CN111181224A CN202010112977.8A CN202010112977A CN111181224A CN 111181224 A CN111181224 A CN 111181224A CN 202010112977 A CN202010112977 A CN 202010112977A CN 111181224 A CN111181224 A CN 111181224A
Authority
CN
China
Prior art keywords
charging
battery
circuit
switch
series
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202010112977.8A
Other languages
Chinese (zh)
Inventor
彭琦
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Individual
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Priority to CN202010112977.8A priority Critical patent/CN111181224A/en
Publication of CN111181224A publication Critical patent/CN111181224A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02JCIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0013Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries acting upon several batteries simultaneously or sequentially
    • H02J7/0014Circuits for equalisation of charge between batteries
    • H02J7/0016Circuits for equalisation of charge between batteries using shunting, discharge or bypass circuits
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02JCIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0013Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries acting upon several batteries simultaneously or sequentially
    • H02J7/0014Circuits for equalisation of charge between batteries
    • H02J7/0019Circuits for equalisation of charge between batteries using switched or multiplexed charge circuits
    • HELECTRICITY
    • H02GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02JCIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0029Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with safety or protection devices or circuits
    • H02J7/0031Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with safety or protection devices or circuits using battery or load disconnect circuits

Abstract

The invention relates to the technical field of charging of a plurality of series battery packs, and aims to provide a charging system for the plurality of series battery packs and a charging method thereof. The invention discloses a charging system for a plurality of series-connected battery packs, which comprises a power supply circuit and a battery management circuit, wherein the power supply input end of the battery management circuit is electrically connected with the power supply output end of the power supply circuit; the battery management circuit comprises a charging switch circuit, the charging switch circuit is divided into a charging input switch circuit and a charging output switch circuit, and a plurality of groups of charging input switch circuits and charging output switch circuits are correspondingly arranged. The invention also discloses a charging method based on the charging system for the multiple series battery packs, which can alternately carry out independent equalizing charging on single batteries in the multiple series battery packs at the later stage of charging. The invention can better provide the equalizing charge function for the battery pack, has better equalizing consistency and higher efficiency, and can not reduce the charge-discharge cycle life of the battery.

Description

Charging system for multi-section series battery pack and charging method thereof
Technical Field
The invention relates to the technical field of charging of a plurality of series battery packs, in particular to a charging system for the plurality of series battery packs and a charging method thereof.
Background
The existing multi-section series rechargeable batteries, especially lithium batteries, have the problems of safety, flammability and explosion, and must be monitored and protected in real time during charging and discharging overcharge, and meanwhile, in the application of a high-voltage large-capacity battery pack, a plurality of single rechargeable batteries need to be connected in series or in parallel to achieve the purposes of high voltage and large capacity. However, the inevitable differences in capacity, performance and internal resistance in the production of each individual cell are present, so that voltage differences occur during both charging and discharging. In the later stage of charging, the voltage imbalance is particularly obvious, and the problem of battery damage is easy to occur. In the later stage of charging, if the average voltage of the single batteries in the whole battery pack does not reach the full-charge condition, but the voltage of the single batteries in the internal part reaches the full-charge voltage, the whole battery pack is continuously charged at the moment, so that the single batteries reaching the full-charge voltage are overcharged, the single batteries are easily damaged, and even charging safety accidents are caused.
In view of the above problems, a Battery Management System (BMS) has been developed in the market for real-time monitoring and protecting the charge and discharge of a Battery, and the existing BMS is mainly classified into the following two types:
a. pure BMS: the battery management system has the most basic BMS function and can realize the charge and discharge management of the battery. In the charging process, if a certain single battery or the whole group of batteries is fully charged or overcharged, the charging is stopped; if a certain single battery or the whole battery is over-discharged in the discharging process, the discharging is stopped. However, such BMS are simple in their functions and do not provide a function of equalizing charge to the batteries, so that it is necessary to perform a capacity test and an internal resistance test on the assembled batteries and group the batteries according to the test results during the assembly of the assembled battery pack, which results in high production requirements and low efficiency. In addition, such BMS cannot solve the problem of the balance difference between the batteries during the charge and discharge processes, and when a certain battery is charged in advance to stop the charging of the entire battery pack, the other batteries are not fully charged, so that the performance of the battery pack cannot be effectively exerted.
b. The BMS of single section battery equalizing function has been increased on former basis, takes equalizing function's BMS promptly: which is to add a charge equalization function to the first BMS. The method is that a discharging circuit is added on the battery management protection board corresponding to each battery. When the charging is overcharged, if the overcharge of a certain single battery is detected, the charging is stopped, then a discharging circuit corresponding to the battery is opened, the battery is discharged to be lower than the safe voltage, and then the charging of the whole battery pack is recovered. By analogy, whenever the overcharge of a certain battery is detected, the overcharge of the battery is eliminated by the method, and finally all the batteries reach the optimal full charge degree. However, the equalization process in the later period of the BMS is long, which may prolong the charging time of the battery pack because the battery needs to be discharged and then recharged, and if the overcharge of a plurality of single cells occurs during the charging process, the equalization charging time must be greatly increased. In addition, the equalization process of such a BMS actually allows the battery to undergo one or more charge-discharge cycles, directly resulting in a loss of the battery cycle charge-discharge life. From the actual conditions of the market, use the lithium cell group of taking balanced function, although can better solution later stage equilibrium problem in charging process, the life cycle of whole group battery all is less than the life who adopts the group battery of first kind BMS far away.
Therefore, the prior art cannot effectively solve the problem of charge-discharge balance of a single battery in the battery pack, cannot effectively exert the actual performance of the battery, and even cannot ensure that the battery reaches the due service life at a user end.
Disclosure of Invention
The present invention is directed to solve the above-mentioned problems to at least some extent, and the present invention provides a charging system for a plurality of series-connected battery packs and a charging method thereof.
The technical scheme adopted by the invention is as follows:
a charging system for a plurality of series-connected battery packs comprises a power supply circuit and a battery management circuit, wherein the power supply input end of the battery management circuit is electrically connected with the power supply output end of the power supply circuit; the battery management circuit comprises a charging switch circuit, the charging switch circuit is divided into a charging input switch circuit and a charging output switch circuit, the power input end of the charging input switch circuit is electrically connected with the output end of the power supply circuit, the power output end of the charging input switch circuit and the power input end of the charging output switch circuit are respectively two-pole wiring ends of any battery in the multi-section series battery pack, the power output end of the charging output switch circuit is grounded, and the charging input switch circuit and the charging output switch circuit are correspondingly provided with multiple groups.
Preferably, the power supply circuit comprises a transformer, a main power switch and a secondary power switch, a primary winding of the transformer is used for connecting a power supply, two secondary windings of the transformer are provided, and the two secondary windings are a first secondary winding and a second secondary winding respectively; one end of the first secondary winding of the transformer is electrically connected with the input end of the main power switch, the other end of the first secondary winding of the transformer is grounded, one end of the second secondary winding of the transformer is electrically connected with the input end of the secondary power switch, the other end of the second secondary winding of the transformer is grounded, and the output end of the main power switch and the output end of the secondary power switch are both electrically connected with the input end of the battery management circuit.
Preferably, the charging system for the multiple series-connected battery packs further comprises a dc conversion circuit and a standby power switch, the dc conversion circuit and the standby power switch are connected in series to form a standby power supply branch, and the standby power supply branch is connected in parallel with the main power switch.
Further preferably, the main power switch outputs a first power supply voltage V1, and the first power supply voltage V1 is used for charging the plurality of series-connected battery packs; the second power supply voltage V2 is output from the power switch, the third power supply voltage V3 is output from the standby power switch, and the second power supply voltage V2 and the third power supply voltage V3 are used for charging a single battery in the multi-series battery pack.
Preferably, the charging system for multiple series-connected battery packs further comprises a detection control circuit, and the detection control circuit is electrically connected with the controlled end of the main power switch, the controlled end of the secondary power switch, the controlled end of the standby power switch, the controlled end of the charging input switch circuit and the controlled end of the charging output switch circuit respectively.
Further preferably, the charge switch circuit includes a first P-type MOS transistor, a first resistor, a second resistor, a first triode, a third resistor, a second P-type MOS transistor, a fourth resistor, a fifth resistor, a second triode, and a sixth resistor; the source electrode of the first P-type MOS tube is a first terminal of the charging switch circuit, the drain electrode of the first P-type MOS tube is electrically connected with the drain electrode of the second P-type MOS tube, and the grid electrode of the first P-type MOS tube is electrically connected with the source electrode of the first P-type MOS tube through a first resistor; the third resistor and the sixth resistor are electrically connected with the base electrode of the second triode through the base electrode one-time pass switch of the first triode, the collector electrode of the first triode is electrically connected with the grid electrode of the first P-type MOS tube through the second resistor, and the emitting electrode of the first triode is grounded; the source electrode of the second P-type MOS tube is a second terminal of the charging switch circuit, the grid electrode of the second P-type MOS tube is electrically connected with the source electrode of the second P-type MOS tube through a fourth resistor, and the grid electrode of the second P-type MOS tube is also electrically connected with the collector electrode of the second triode through a fifth resistor; the emitter of the second triode is grounded; and the joint point of the third resistor and the sixth resistor is electrically connected with the detection control circuit.
A charging method based on the charging system for the plurality of series-connected battery packs comprises the following steps;
the detection control circuit drives the main power switch to be closed and drives the auxiliary power switch and the standby power switch to be disconnected, and the power supply circuit carries out charging operation on the plurality of series-connected battery packs through the battery management circuit;
the detection control circuit detects the voltage of each battery in the plurality of series battery packs in real time, and when the voltage of any battery reaches the maximum threshold value of the battery voltage, the detection control circuit drives the main power switch to be switched off;
the detection control circuit drives the slave power switch or the standby power switch to be closed and drives a group of charging input switch circuits and charging output switch circuits to be closed, and the power supply circuit carries out charging operation on batteries corresponding to the group of charging input switch circuits and the charging output switch circuits;
the detection control circuit detects the voltage of the battery performing the charging operation in real time, when the voltage of the battery performing the charging operation reaches the maximum voltage threshold value or the charging time threshold value of the battery, the detection control circuit drives the charging input switch circuit and the charging output switch circuit corresponding to the battery performing the charging operation to be disconnected, and drives the other group of charging input switch circuit and the equalizing charging switch circuit to be closed, and the power supply circuit performs corresponding charging operation on the corresponding battery; repeating the steps until all the batteries in the plurality of series battery packs complete the charging operation.
Preferably, the method further comprises the following steps:
the detection control circuit detects the discharge voltage of the plurality of series battery packs, and when the discharge voltage of the plurality of battery packs is lower than the lowest threshold value of the battery packs, the detection control circuit sequentially opens each group of the charge input switch circuit and the charge output switch circuit and respectively detects the current voltage of each battery in the plurality of series battery packs; when the voltage of any battery in the plurality of series battery packs is lower than the conventional threshold value of the voltage of the battery, the detection control circuit drives the charging input switch circuit and the charging output switch circuit corresponding to the battery to be closed, and the battery is charged.
Preferably, when the detection control circuit drives the slave power switch or the standby power switch to be turned on and off, the specific steps are as follows: the detection control circuit detects whether the secondary power supply switch outputs the second power supply voltage V2, if so, the detection control circuit drives the secondary power supply switch to close; if not, the detection control circuit drives the standby power switch to be switched on and off.
The invention has the beneficial effects that:
the charging system for the multi-section series battery pack can better provide the equalizing charging function for the battery pack, has better equalizing consistency and higher efficiency, and does not reduce the charge-discharge cycle life of the battery.
In the charging method of the charging system for the plurality of series battery packs, after the charging system for the plurality of series battery packs charges the whole plurality of series battery packs, the detection control circuit drives the power supply circuit and the battery management circuit to independently charge any battery in the plurality of series battery packs, and charges all batteries in the plurality of series battery packs in a rotating mode, and the batteries in the plurality of series battery packs can be charged only by one sampling circuit and one charging channel, so that the final voltage and electric quantity results of each battery in the plurality of series battery packs are basically consistent, the sampling error and the charging voltage error do not exist, the problems of external circuit sampling error and charging consistency difference in the balancing process are effectively solved, and the discharging performance of the batteries can be greatly improved. In addition, because the invention can fully fill each battery in the multi-section series battery pack to a consistent voltage level, the pairing requirement of the capacity and the internal resistance of each battery in the production and assembly process of the battery pack is greatly reduced, thereby effectively improving the production efficiency of the multi-section series battery pack and saving the production cost.
Drawings
FIG. 1 is a schematic diagram showing the construction of a main power switch, a DC converter circuit, a backup power switch, a battery management circuit, a plurality of series-connected battery packs, and a load in embodiment 1;
fig. 2 is a schematic structural diagram of a transformer in the power supply circuit in embodiment 1;
fig. 3 is a schematic circuit diagram of the dc converter circuit and the standby power switch in embodiment 1;
fig. 4 is a circuit schematic diagram of a battery management circuit in embodiment 1;
fig. 5 is a schematic circuit diagram of the battery management circuit in embodiment 1 for charging all the batteries in a plurality of series-connected battery packs.
Fig. 6 is a schematic circuit diagram of a battery management circuit for charging any one of a plurality of series-connected battery packs in embodiment 1.
Detailed Description
The invention is further described with reference to the following figures and specific embodiments. It should be noted that the description of the embodiments is provided to help understanding of the present invention, but the present invention is not limited thereto. Specific structural and functional details disclosed herein are merely illustrative of example embodiments of the invention. This invention may, however, be embodied in many alternate forms and should not be construed as limited to the embodiments set forth herein.
It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of example embodiments of the present invention.
It should be understood that, for the term "and/or" as may appear herein, it is merely an associative relationship that describes an associated object, meaning that three relationships may exist, e.g., a and/or B may mean: a exists alone, B exists alone, and A and B exist at the same time; for the term "/and" as may appear herein, which describes another associative object relationship, it means that two relationships may exist, e.g., a/and B, may mean: a exists independently, and A and B exist independently; in addition, for the character "/" that may appear herein, it generally means that the former and latter associated objects are in an "or" relationship.
It will be understood that when an element is referred to herein as being "connected," "connected," or "coupled" to another element, it can be directly connected or coupled to the other element or intervening elements may be present. Conversely, if a unit is referred to herein as being "directly connected" or "directly coupled" to another unit, it is intended that no intervening units are present. In addition, other words used to describe the relationship between elements should be interpreted in a similar manner (e.g., "between … …" versus "directly between … …", "adjacent" versus "directly adjacent", etc.).
It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments of the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises," "comprising," "includes" and/or "including," when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, elements, components, and/or groups thereof.
It should also be noted that, in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may, in fact, be executed substantially concurrently, or the figures may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
It should be understood that specific details are provided in the following description to facilitate a thorough understanding of example embodiments. However, it will be understood by those of ordinary skill in the art that the example embodiments may be practiced without these specific details. For example, systems may be shown in block diagrams in order not to obscure the examples in unnecessary detail. In other instances, well-known processes, structures and techniques may be shown without unnecessary detail in order to avoid obscuring example embodiments.
Example 1:
the present embodiment provides a charging system for a plurality of series-connected battery packs, as shown in fig. 1, including a power supply circuit and a battery management circuit, wherein a power input terminal of the battery management circuit is electrically connected to a power output terminal of the power supply circuit; the battery management circuit comprises a charging switch circuit, the charging switch circuit is divided into a charging input switch circuit and a charging output switch circuit, the power input end of the charging input switch circuit is electrically connected with the output end of the power supply circuit, the power output end of the charging input switch circuit and the power input end of the charging output switch circuit are respectively the two-pole wiring ends of any battery in the multiple series-connected battery packs, the power output end of the charging output switch circuit is grounded, and multiple groups of charging input switch circuits and multiple groups of charging output switch circuits are correspondingly arranged.
In this embodiment, as shown in fig. 2, the power supply circuit includes a transformer MC1, a master power switch and a slave power switch KV2The primary winding L1 of the transformer MC1 is used for being connected with a power supply AC, two secondary windings of the transformer MC1 are arranged, and the two secondary windings are a first secondary winding L2 and a second secondary winding L3 respectively; one end of a first secondary winding L2 of the transformer MC1 is electrically connected with the input end of the main power switch, the other end of a first secondary winding L2 of the transformer MC1 is grounded, and one end of a second secondary winding L3 of the transformer MC1 is connected with the auxiliary power switch KV2Is electrically connected, the other end of the second secondary winding L3 of the transformer MC1 is grounded, the output end of the main power switch and the slave power switch K are connectedV2The output ends of the battery management circuits are all electrically connected with the input end of the battery management circuit.
Furthermore, the charging system for the multiple series battery packs further comprises a DC conversion circuit and a standby power switch KV3DC conversion circuit and standby power switch KV3As shown in FIG. 3, a DC conversion circuit and a standby power switch KV3The standby power supply branch circuit is formed by connecting in series and is connected with the main power switch in parallel. In this embodiment, the input terminal of the dc conversion circuit is electrically connected to the junction between one end of the first secondary winding L2 and the input terminal of the main power switch, and the output terminal of the dc conversion circuit is electrically connected to the backup power switch KV3Is electrically connected with the input end of the standby power switch KV3The output end of the DC conversion circuit is electrically connected with the input end of the battery management circuit, and the DC conversion circuit can convert the voltage output by the main power switch into the voltage capable of charging a single battery.
Specifically, the main power switch outputs a first supply voltage V1, and the first supply voltage V1 is used for charging the multiple series-connected battery packs; slave power switch KV2The output of the standby power switch K is provided with a second power supply voltage V2V3The third supply voltage V3 is outputted, and the second supply voltage V2 and the third supply voltage V3 are used for charging a single battery in the plurality of series-connected battery packs. In this embodiment, the first supply voltage V1 is a normal charging demand voltage of the battery pack, and the second supply voltage V2 and the third supply voltage V3 are both the highest charging voltage of a single battery in the battery pack, and are used for equalizing and charging the single battery in the multiple series battery packs.
Furthermore, the charging system for the multiple series-connected battery packs further comprises a detection control circuit, and the detection control circuit is respectively connected with the controlled end of the main power switch and the slave power switch KV2Controlled end, standby power switch KV3The controlled end of the charging input switch circuit and the controlled end of the charging output switch circuit are electrically connected.
In this embodiment, the charge switch circuit includes a first P-type MOS transistor, a first resistor, a second resistor, a first triode, a third resistor, a second P-type MOS transistor, a fourth resistor, a fifth resistor, a second triode, and a sixth resistor; the source electrode of the first P-type MOS tube is a first terminal of the charging switch circuit, the drain electrode of the first P-type MOS tube is electrically connected with the drain electrode of the second P-type MOS tube, and the grid electrode of the first P-type MOS tube is electrically connected with the source electrode of the first P-type MOS tube through a first resistor; the third resistor and the sixth resistor are electrically connected with the base electrode of the second triode through the base electrode one-time pass switch of the first triode, the collector electrode of the first triode is electrically connected with the grid electrode of the first P-type MOS tube through the second resistor, and the emitting electrode of the first triode is grounded; the source electrode of the second P-type MOS tube is a second terminal of the charging switch circuit, the grid electrode of the second P-type MOS tube is electrically connected with the source electrode of the second P-type MOS tube through a fourth resistor, and the grid electrode of the second P-type MOS tube is also electrically connected with the collector electrode of the second triode through a fifth resistor; the emitter of the second triode is grounded; and the joint point of the third resistor and the sixth resistor is electrically connected with the detection control circuit. It should be understood that the circuit arrangement of the charge input switch circuit and the charge output switch circuit is the same, wherein the first terminal of the charge input switch circuit is electrically connected with the power supply output terminal of the power supply circuit, and the second terminal of the charge input switch circuit is electrically connected with the positive electrode of the corresponding battery; the first terminal of the charging output switch circuit is electrically connected with the negative pole of the corresponding battery; the second terminal of the charging output switch circuit is grounded.
Specifically, fig. 4 is a schematic circuit diagram of a battery management circuit, in fig. 4, the battery management circuit is electrically connected to batteries BT1, BT2, BT3, …, and BTm in a plurality of series-connected battery packs, respectively, wherein a positive electrode of the battery BT1 is electrically connected to a second terminal of the first charge input switch circuit KB1a, a first terminal of the first charge input switch circuit KB1a is electrically connected to a power output terminal of the power supply circuit, a negative electrode of the battery BT1 is electrically connected to a first terminal of the first charge output switch circuit KB2b, and the connection manner of the batteries BT2, BT3, …, and BTm to the corresponding charge switch circuit is similar to that of the battery BT1 and will not be described herein.
In the charging process, firstly, a first power supply voltage V1 output by a main power switch charges a plurality of series-connected battery packs; the detection control circuit detects the voltage of each battery in the multiple series battery packs in real time, when the voltage of any battery reaches the maximum threshold value of the battery voltage, the detection control circuit drives the main power switch to be switched off, then the detection control circuit drives the charging switch circuit corresponding to any battery to act, and the second power supply voltage V2 or the third power supply voltage V3 charges the single batteries in the multiple series battery packs in turn.
Specifically, when a single battery is charged, the operation principle of the battery management circuit is described by taking charging of the battery BT1 as an example: in the current loop of the positive electrode of the battery BT1, the detection control circuit drives the first charge input switch circuit KB1a to close, that is, the detection control circuit drives the first P-type MOS transistor Q5 to close through the first triode Q2, and drives the second P-type MOS transistor Q12 to close through the second triode Q14, so as to achieve that the current (denoted by Vc + in fig. 4) corresponding to the second supply voltage V2 or the third supply voltage V3 is conducted between the first P-type MOS transistor Q5 and the second P-type MOS transistor Q12, but at the same time, the other charge input switch circuit and the charge output switch circuit must be driven to open, so that the current of Vc + reaches the positive electrode of BT1+ (i.e., the positive electrode of the battery BT 1), and the second supply voltage V2 or the third supply voltage V3 is loaded to the positive electrode of the battery BT 1. In the current loop of the negative electrode of the battery BT1, the detection control circuit drives the first charging output switch circuit KB2b to close, that is, the detection control circuit drives the first transistor Q19 to close the first P-type MOS transistor Q28, and drives the second transistor Q20 to close the second P-type MOS transistor Q31, so that the current flowing through the BT2+ electrode (i.e., the BT 1-electrode, the positive electrode of the battery BT 1) can flow back to Vc-through the first transistor Q28 and the second P-type MOS transistor Q31.
It should be noted that the present embodiment can be applied to all types of rechargeable batteries, including but not limited to various types of rechargeable batteries such as lithium batteries, nickel-metal hydride batteries, lead-acid batteries, etc., and is widely applicable.
In the implementation process of the embodiment, the voltage output by the power supply circuit is sequentially loaded on a certain single battery in a plurality of series battery packs through the control of a plurality of groups of charging input switch circuits and charging output switch circuits in the battery management circuit, so that the charging operation of the plurality of series battery packs is realized, the final voltage and electric quantity results of each battery in the plurality of series battery packs can be basically consistent, no sampling error and no charging voltage error exist, and the problems of sampling errors and charging consistency differences of external circuits in the equalization process are effectively solved.
Example 2:
the present embodiment provides a charging method based on the charging system for multiple series battery packs in embodiment 1, including the following steps;
the detection control circuit drives the main power switch to be closed and drives the secondary power switch KV2And a standby power switch KV3When the battery management circuit is disconnected, the power supply circuit performs charging operation on the plurality of series-connected battery packs through the battery management circuit; at this time, the first power supply voltage V1 output by the main power switch is used to charge the multiple series-connected battery packs, and the charging schematic diagram is shown in fig. 5;
the detection control circuit detects the voltage of each battery in the plurality of series battery packs in real time, and when the voltage of any battery reaches the maximum threshold value of the battery voltage, the detection control circuit drives the main power switch to be switched off;
detection control circuit drives slave power switch KV2Or a standby power switch KV3Closing the charging input switch circuit and the charging output switch circuit, and driving any group of charging input switch circuit and charging output switch circuit to be closed, wherein the power supply circuit carries out charging operation on the batteries corresponding to the charging input switch circuit and the charging output switch circuit; at this moment, the slave power switch KV2The output second power supply voltage V2 or the standby power switch KV3The output third power supply voltage V3 charges single batteries in the multiple series battery packs, which is the power supply circuit performs equalizing charge on the single batteries in the multiple series battery packs through the battery management circuit, so that the problem that the batteries in the multiple series battery packs cannot be fully charged is avoided;
the detection control circuit detects the voltage of the battery performing the charging operation in real time, when the voltage of the battery performing the charging operation reaches the maximum voltage threshold value or the charging time threshold value of the battery, the detection control circuit drives a charging input switch circuit and a charging output switch circuit corresponding to the battery performing the charging operation to be disconnected, and drives another group of charging input switch circuit and an equalizing charging switch circuit to be closed, and the power supply circuit performs corresponding charging operation on the battery corresponding to the group of charging input switch circuit and the equalizing charging switch circuit; repeating the steps until all the batteries in the plurality of series battery packs complete the charging operation. In this embodiment, a schematic diagram of a power flow direction structure when the battery management circuit charges all the batteries in the plurality of series-connected battery packs is shown in fig. 5, and a schematic diagram of a power flow direction structure when the battery management circuit charges any one of the batteries in the plurality of series-connected battery packs is shown in fig. 6.
In this embodiment, the charging system for multiple series battery packs can alternately and independently charge the single batteries in the multiple series battery packs in an equalizing process at the later stage of charging, and specifically, after the charging system for multiple series battery packs charges the whole multiple series battery packs, the detection control circuit drives the power supply circuit and the battery management circuit to independently charge any battery in the multiple series battery packs, and charges all the batteries in the multiple series battery packs in an alternate manner, so that the charging system can charge the batteries in the multiple series battery packs only by one sampling circuit and one charging channel, thereby ensuring that the final voltage and electric quantity results of each battery in the multiple series battery packs are basically consistent, and having no sampling error and charging voltage error, thereby effectively solving the problems of sampling error and charging consistency difference of external circuits in the equalizing process, the discharge performance of the battery can be greatly improved. In addition, because the embodiment can fully fill each battery in the plurality of series-connected battery packs to a consistent voltage level, the pairing requirement on the capacity and the internal resistance of each battery in the production and assembly process of the battery packs is greatly reduced, the production efficiency of the plurality of series-connected battery packs is effectively improved, and the production cost is saved.
In this embodiment, the method further includes the following steps:
the detection control circuit detects the discharge voltage of the plurality of series battery packs, and when the discharge voltage of the plurality of battery packs is lower than the lowest threshold value of the battery packs, the detection control circuit sequentially opens each group of the charge input switch circuit and the charge output switch circuit and respectively detects the current voltage of each battery in the plurality of series battery packs; when the voltage of any battery in the plurality of series-connected battery packs is lower than the battery voltageNormal threshold value VBcAnd when the battery is charged, the detection control circuit drives the charging input switch circuit and the charging output switch circuit corresponding to the battery to be closed, so that the battery can be charged, current compensation can be carried out on the battery, and the battery is prevented from being discharged too fast. Further, when the voltage of any battery in the plurality of series-connected battery packs is lower than the minimum threshold V of the batteryBdWhen the battery pack is in a normal state, the detection control circuit drives the discharge switch between the plurality of series battery packs and the load to be switched off, so that the output of the whole battery pack is closed, and the battery is prevented from being damaged by over-discharge. The embodiment can avoid repeated discharging and recharging operations on the multiple series-connected battery packs and avoid influencing the charging and discharging cycle life of the batteries, thereby effectively prolonging the service life of the multiple series-connected battery packs in the actual use process and theoretically ensuring that the service life of the battery packs is consistent with the electrochemical cycle service life of a single battery.
Specifically, in this embodiment, two poles of the plurality of series-connected battery packs are electrically connected to the load, a discharge switch is disposed between the load and the plurality of series-connected battery packs, and the detection control circuit is electrically connected to a controlled terminal of the discharge switch.
In this embodiment, the detection control circuit drives the slave power switch KV2Or a standby power switch KV3When closing, the concrete steps are as follows: the detection control circuit detects the slave power switch KV2Whether the second power supply voltage V2 is output or not, if yes, the detection control circuit drives the slave power switch KV2Closing; if not, the detection control circuit drives the standby power switch KV3And (5) closing. I.e. the slave power switch KV2Is higher than the standby power switch KV3The priority of (2).
The various embodiments described above are merely illustrative, and may or may not be physically separate, as they relate to elements illustrated as separate components; if reference is made to a component displayed as a unit, it may or may not be a physical unit, and may be located in one place or distributed over a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: modifications of the technical solutions described in the embodiments or equivalent replacements of some technical features may still be made. And such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Finally, it should be noted that the present invention is not limited to the above alternative embodiments, and that various other forms of products can be obtained by anyone in light of the present invention. The above detailed description should not be taken as limiting the scope of the invention, which is defined in the claims, and which the description is intended to be interpreted accordingly.

Claims (9)

1. A charging system for a plurality of series-connected battery packs is characterized in that: the battery management circuit comprises a power supply circuit and a battery management circuit, wherein a power supply input end of the battery management circuit is electrically connected with a power supply output end of the power supply circuit; the battery management circuit comprises a charging switch circuit, the charging switch circuit is divided into a charging input switch circuit and a charging output switch circuit, the power input end of the charging input switch circuit is electrically connected with the output end of the power supply circuit, the power output end of the charging input switch circuit and the power input end of the charging output switch circuit are respectively two-pole wiring ends of any battery in the multi-section series battery pack, the power output end of the charging output switch circuit is grounded, and the charging input switch circuit and the charging output switch circuit are correspondingly provided with multiple groups.
2. The charging system for a plurality of series-connected battery packs as claimed in claim 1, wherein: the power supply circuit comprises a transformer, a main power switch and a secondary power switch, wherein a primary winding of the transformer is used for connecting a power supply, two secondary windings of the transformer are arranged, and the two secondary windings are a first secondary winding and a second secondary winding respectively; one end of the first secondary winding of the transformer is electrically connected with the input end of the main power switch, the other end of the first secondary winding of the transformer is grounded, one end of the second secondary winding of the transformer is electrically connected with the input end of the secondary power switch, the other end of the second secondary winding of the transformer is grounded, and the output end of the main power switch and the output end of the secondary power switch are both electrically connected with the input end of the battery management circuit.
3. The charging system for a plurality of series-connected battery packs as claimed in claim 2, wherein: the charging system for the multiple series-connected battery packs further comprises a direct current conversion circuit and a standby power switch, wherein the direct current conversion circuit and the standby power switch are connected in series to form a standby power supply branch, and the standby power supply branch is connected with the main power switch in parallel.
4. A charging system for a plurality of series-connected battery packs as claimed in claim 3, wherein: the main power switch outputs a first supply voltage V1, and the first supply voltage V1 is used for charging the plurality of series-connected battery packs; the second power supply voltage V2 is output from the power switch, the third power supply voltage V3 is output from the standby power switch, and the second power supply voltage V2 and the third power supply voltage V3 are used for charging a single battery in the multi-series battery pack.
5. The charging system for a plurality of series-connected battery packs as claimed in claim 4, wherein: the charging system for the multiple series-connected battery packs further comprises a detection control circuit, wherein the detection control circuit is respectively and electrically connected with the controlled end of the main power switch, the controlled end of the auxiliary power switch, the controlled end of the standby power switch, the controlled end of the charging input switch circuit and the controlled end of the charging output switch circuit.
6. The charging system for a plurality of series-connected battery packs as claimed in claim 5, wherein: the charging switch circuit comprises a first P-type MOS tube, a first resistor, a second resistor, a first triode, a third resistor, a second P-type MOS tube, a fourth resistor, a fifth resistor, a second triode and a sixth resistor; the source electrode of the first P-type MOS tube is a first terminal of the charging switch circuit, the drain electrode of the first P-type MOS tube is electrically connected with the drain electrode of the second P-type MOS tube, and the grid electrode of the first P-type MOS tube is electrically connected with the source electrode of the first P-type MOS tube through a first resistor; the third resistor and the sixth resistor are electrically connected with the base electrode of the second triode through the base electrode one-time pass switch of the first triode, the collector electrode of the first triode is electrically connected with the grid electrode of the first P-type MOS tube through the second resistor, and the emitting electrode of the first triode is grounded; the source electrode of the second P-type MOS tube is a second terminal of the charging switch circuit, the grid electrode of the second P-type MOS tube is electrically connected with the source electrode of the second P-type MOS tube through a fourth resistor, and the grid electrode of the second P-type MOS tube is also electrically connected with the collector electrode of the second triode through a fifth resistor; the emitter of the second triode is grounded; and the joint point of the third resistor and the sixth resistor is electrically connected with the detection control circuit.
7. A charging method of the charging system for a plurality of series-connected battery packs according to claim 5 or 6, characterized in that: comprises the following steps;
the detection control circuit drives the main power switch to be closed and drives the auxiliary power switch and the standby power switch to be disconnected, and the power supply circuit carries out charging operation on the plurality of series-connected battery packs through the battery management circuit;
the detection control circuit detects the voltage of each battery in the plurality of series battery packs in real time, and when the voltage of any battery reaches the maximum threshold value of the battery voltage, the detection control circuit drives the main power switch to be switched off;
the detection control circuit drives the slave power switch or the standby power switch to be closed and drives a group of charging input switch circuits and charging output switch circuits to be closed, and the power supply circuit carries out charging operation on batteries corresponding to the group of charging input switch circuits and the charging output switch circuits;
the detection control circuit detects the voltage of the battery performing the charging operation in real time, when the voltage of the battery performing the charging operation reaches the maximum voltage threshold value or the charging time threshold value of the battery, the detection control circuit drives the charging input switch circuit and the charging output switch circuit corresponding to the battery performing the charging operation to be disconnected, and drives the other group of charging input switch circuit and the equalizing charging switch circuit to be closed, and the power supply circuit performs corresponding charging operation on the corresponding battery; repeating the steps until all the batteries in the plurality of series battery packs complete the charging operation.
8. The charging method of a charging system for a plurality of series-connected battery packs as claimed in claim 7, wherein: further comprising the steps of:
the detection control circuit detects the discharge voltage of the plurality of series battery packs, and when the discharge voltage of the plurality of battery packs is lower than the lowest threshold value of the battery packs, the detection control circuit sequentially opens each group of the charge input switch circuit and the charge output switch circuit and respectively detects the current voltage of each battery in the plurality of series battery packs; when the voltage of any battery in the plurality of series battery packs is lower than the conventional threshold value of the voltage of the battery, the detection control circuit drives the charging input switch circuit and the charging output switch circuit corresponding to the battery to be closed, and the battery is charged.
9. The charging method of a charging system for a plurality of series-connected battery packs as claimed in claim 7, wherein: when the detection control circuit drives the slave power switch or the standby power switch to be switched on, the specific steps are as follows: the detection control circuit detects whether the secondary power supply switch outputs the second power supply voltage V2, if so, the detection control circuit drives the secondary power supply switch to close; if not, the detection control circuit drives the standby power switch to be switched on and off.
CN202010112977.8A 2020-02-24 2020-02-24 Charging system for multi-section series battery pack and charging method thereof Pending CN111181224A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010112977.8A CN111181224A (en) 2020-02-24 2020-02-24 Charging system for multi-section series battery pack and charging method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010112977.8A CN111181224A (en) 2020-02-24 2020-02-24 Charging system for multi-section series battery pack and charging method thereof

Publications (1)

Publication Number Publication Date
CN111181224A true CN111181224A (en) 2020-05-19

Family

ID=70658459

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010112977.8A Pending CN111181224A (en) 2020-02-24 2020-02-24 Charging system for multi-section series battery pack and charging method thereof

Country Status (1)

Country Link
CN (1) CN111181224A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113708442A (en) * 2021-08-14 2021-11-26 北京动力京工科技有限公司 Bypass type battery equalization device and control method
CN113725977A (en) * 2021-09-06 2021-11-30 吴才荣 Charging and recharging circuit for series storage battery pack

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113708442A (en) * 2021-08-14 2021-11-26 北京动力京工科技有限公司 Bypass type battery equalization device and control method
CN113725977A (en) * 2021-09-06 2021-11-30 吴才荣 Charging and recharging circuit for series storage battery pack

Similar Documents

Publication Publication Date Title
CN101740827B (en) Active equalization system of lithium-ion power battery and equalization method thereof
CN102545291B (en) Solar power storage system and solar power supply system
US9136715B2 (en) Rechargeable battery pack and method of charge/discharge equalizing
CN200990518Y (en) Buffer circuit of accumulator pile charging and discharging
US20230027457A1 (en) A Parallel Charging and Discharging Management System of Multiple Batteries
CN201478865U (en) Improved charging balanced circuit
CN101826745A (en) Lithium ion power battery lossless charger
CN107658936A (en) A kind of battery detection and equalizing system and its control method
CN203377638U (en) Switching-type battery pack charging discharging protection equalization circuit
WO2017212815A1 (en) Trickle charging power supply system
CN103036256A (en) Transformer scan chain type storage battery equalizing circuit and method
CN111181224A (en) Charging system for multi-section series battery pack and charging method thereof
CN114914990A (en) Charge-discharge balance control method for built-in battery pack of portable electrical appliance
CN103501036B (en) A kind of charging and discharging lithium battery pilot circuit
CN103117576B (en) Storage battery voltage balancing device
CN103036277B (en) Equalizer circuit of dynamic and energy storage battery pack
CN112737015B (en) Lithium battery balance control system and control method based on SOC
CN102136750B (en) Monomer charging and discharging tail balancing module and battery pack balancing protection management system thereof
CN2922234Y (en) Over-discharge protecting circuit for power lithium ion cell
CN102231516A (en) Battery protection board, power battery and power battery pack
CN201113460Y (en) Self-switching type battery control circuit and its charger
CN114884168B (en) Transformer substation direct current system based on lithium iron phosphate storage battery
CN211701533U (en) Charging system for multi-section series battery pack
CN207117203U (en) A kind of lithium-ion energy storage unit and unit group
CN2922233Y (en) Over-charging protecting circuit for power lithium ion cell

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination