Series charging and discharging device with uninterrupted current

Abstract

The present invention relates to a method and device for serial charging and discharging of multiple secondary batteries with an uninterrupted current, wherein the method and device for serially charging and discharging multiple secondary batteries using a bidirectional main charging and discharging power supply device is configured to eliminate the capacity difference of a single battery by adding an auxiliary charging power supply device in parallel to the single battery, and continuously charge and discharge according to a predetermined formula (electrical conditions for charging and discharging, etc.) without interrupting (on / off) the charging and discharging current of the main charging and discharging power supply device.

Description

Technical Field

[0001] The present invention provides a method and device for serial charging and discharging of multiple secondary batteries with an uninterrupted current, wherein the method and device for serially charging and discharging multiple secondary batteries using a bidirectional main charging and discharging power supply device is configured to eliminate the capacity difference of a single battery by adding an auxiliary charging power supply device in parallel to the single battery, and continuously charge and discharge according to a predetermined formula without interrupting (on / off) the charging and discharging current of the main charging and discharging power supply device. Background Art

[0002] Secondary batteries (a general term for batteries that are repeatedly charged and discharged, such as lithium batteries) are charged and discharged according to a predetermined recipe (electrical conditions for charging and discharging, etc.) during manufacturing and use.

[0003] This is a very important process in the manufacturing process of secondary batteries because the quality of batteries is judged and sorted based on the results of the charge and discharge operation characteristics.

[0004] As the production of large-capacity secondary batteries for electric vehicles has exploded, the charging and discharging devices not only greatly increase the equipment cost, but the electricity consumed during use and the accompanying cooling and heating are important factors affecting the economic feasibility of secondary batteries. At the same time, measurement and detection functions are needed to improve the safety of secondary batteries during the charging and discharging process.

[0005] Secondary batteries have the characteristic that the voltage and current change according to the amount of charge and discharge. In the conventional charging formula, when constant current charging is performed at a predetermined current, the battery voltage will gradually increase, and after reaching the predetermined set voltage (or maximum voltage), the predetermined set voltage will be maintained, and the charging current will gradually decrease. When the predetermined set current (or cut-off current) is reached, the charging process is completed.

[0006] In a conventional discharge recipe, if the battery is discharged at a predetermined constant current, the voltage of the battery gradually decreases, and when the predetermined voltage (or cut-off voltage) is reached, the discharge process is completed.

[0007] In secondary batteries, even if charging and discharging are performed with the same current, the voltage fluctuation of a battery with a large battery capacity is small. When multiple batteries are charged and discharged in series, there is a problem that charging and discharging cannot be performed according to the charge and discharge recipe unless there is a device to correct the capacity difference.

[0008] In order to connect or separate multiple secondary batteries in series, a relay switch must be used in the circuit. However, if the battery whose charging or discharging process is completed first is to be separated from the circuit, the current of the main charging and discharging power supply device will be interrupted (on / off) at the moment the relay switch is operated, and errors may occur when measuring current and voltage.

[0009] In order to maintain high accuracy and resolution, voltage and current sensors of devices that charge and discharge a plurality of secondary batteries in series originally use high-specification (usually expensive) sensors and are calibrated regularly.

[0010] The safety of secondary battery charging and discharging devices is a very important factor, and the function of detecting major risk factors in real time is crucial to the safety of the device.

[0011] When the charging and discharging device is in operation, problems such as heating or deformation of the battery itself may occur. Voltage drop or heating caused by poor contact of the battery electrodes is the most common risk factor.

[0012] The charging and discharging devices for secondary batteries are usually unmanned automated equipment. If necessary, the application program must be improved or upgraded. However, if the number of devices running at high voltage and high current is too large, there is a problem of difficulty in modifying or upgrading the control program. Summary of the invention

[0013] Technical issues

[0014] The technical problem to be solved by the present invention is to provide a method and device for serial charging and discharging with uninterrupted current and automatic control, which is configured to use a bidirectional main charging and discharging power supply device to perform serial charging and discharging on multiple secondary batteries so that the charging and discharging current of the battery is not interrupted (on / off), thereby simplifying the charging and discharging device into one, thereby reducing equipment cost and operating cost.

[0015] Another technical problem to be solved by the present invention is to provide a method and device for serial charging and discharging with uninterrupted current and automatic control, which is configured to use a bidirectional main charging and discharging power supply device to perform serial charging and discharging on multiple secondary batteries so that the charging and discharging current of the battery is not interrupted (on / off), thereby enabling the operating voltage of the main charging and discharging device to be higher than the voltage of one battery by a multiple of the number of batteries, thereby improving the efficiency of power conversion and reducing equipment cost and operating cost.

[0016] Another technical problem to be solved by the present invention is to provide a method and device for series charging and discharging with uninterrupted current and automatic control, which is configured to use a bidirectional main charging and discharging power supply device to perform series charging and discharging on multiple secondary batteries so that the charging and discharging current of the battery is not interrupted (on / off), and it is also configured to correct the capacity difference between single-cell batteries by adding an auxiliary charging power supply device in parallel to multiple single-cell batteries in series.

[0017] Another technical problem to be solved by the present invention is to provide a method and device for serial charging and discharging with uninterrupted current and automatic control, wherein an auxiliary charging power supply device is used to correct the capacity difference between single-cell batteries, and is composed of an insulated unidirectional DC converter (DC-DC converter). The insulated unidirectional DC converter takes a DC grid power supply, i.e., the input end of the main charger and discharger, or a separate external power supply as input, and takes the voltage of a single-cell battery as output.

[0018] Another technical problem to be solved by the present invention is to provide a series charging and discharging method and device with uninterrupted current and automatic control, wherein, since a series charging and discharging method and device using multiple secondary batteries are connected in series, the current sensor of the general specification of a single battery can be automatically calibrated regularly according to the high-specification current sensor of the main charging and discharging power supply device, thereby reducing manufacturing costs.

[0019] The object is to provide a series charging and discharging method and device, wherein, since the gain value change, offset value and drift value of the general specification current sensor of a single battery caused by long-term operation are regularly and accurately corrected, the low-cost general specification current sensor can exhibit the same or similar characteristics as the performance of a high specification current sensor.

[0020] Another technical problem to be solved by the present invention is to provide a series charging and discharging method and device, wherein, due to the addition of a function of comparing the output voltage of the main charging and discharging power supply device with the total voltage of a single battery in real time, the abnormal state of the contact part including the single battery can be confirmed in real time, and the potential difference that is expected to generate heat can be identified in real time, thereby preventing accidents in advance, and compared with the existing method of judging the heating state, the safety of the charging and discharging power supply device can be improved.

[0021] Another technical problem to be solved by the present invention is to provide a series charging and discharging method and device, wherein, when the control program of the series charging and discharging device is to be modified or upgraded, there is no need to modify or upgrade the program of the charging and discharging controller of a single battery, and only the controller of the main charging and discharging power supply device, which is far less than the number of batteries, needs to be modified or upgraded through remote communication, thereby greatly improving the ease of subsequent management of the equipment.

[0022] Technical Solution

[0023] The technical solution of the present invention is to provide a method and device for serial charging and discharging of multiple secondary batteries with an uninterrupted current, wherein the method and device for serially charging and discharging multiple secondary batteries using a bidirectional main charging and discharging power supply device is configured to correct and eliminate the capacity difference of a single battery by adding an auxiliary charging power supply device in parallel to a single battery, and continuously charge and discharge according to a predetermined charging and discharging formula without interrupting (on / off) the charging and discharging current of the main charging and discharging power supply device.

[0024] Another technical solution of the present invention is to provide a method and device for serial charging and discharging of uninterrupted current, wherein the electrical input of the auxiliary charging power supply device is composed of a DC grid power supply, that is, the input end of the main charging and discharging power supply device, or is composed of one of separate DC and AC powers, and its output is composed of an insulated unidirectional switch mode DC converter, which outputs the voltage of a single battery cell, and the auxiliary charging power supply device is composed of a separate controller including a microcontroller, which is configured to increase or decrease the voltage and current of a single battery cell.

[0025] Another technical solution of the present invention is to provide a method and device for serial charging and discharging with uninterrupted current, which is configured such that during serial charging, when the main charging and discharging power supply device is charged with a predetermined constant current according to a predetermined charging formula, the voltage of the "battery with the smallest capacity" first reaches a predetermined set voltage (or maximum voltage, such as 4,200mV for lithium batteries), and the main charging and discharging power supply device performs constant voltage charging according to the "battery with the smallest capacity" (charging current according to a predetermined formula), and other batteries with larger capacities use the auxiliary charging power supply device to supplement insufficient charging current according to a predetermined charging formula, so that all single-cell batteries are charged according to a predetermined charging formula under uninterrupted (on / off) current.

[0026] Another technical aspect of the present invention is to provide an uninterrupted series charging and discharging method and device, wherein an auxiliary charging power supply device is used to correct the capacity difference between single-cell batteries, which is composed of an insulated unidirectional DC converter (DC-DC converter), which takes a DC grid power supply, i.e., the input end of the main charger and discharger, or a separate external power supply as input, and takes the voltage of a single-cell battery as output, and is configured to supplement the charging current for the battery with a larger capacity during the charging process of the batteries in series according to the present invention, and to supplement the discharge current for the battery with a smaller capacity during the discharge process.

[0027] Another technical solution of the present invention is to provide a method and device for series charging and discharging with uninterrupted current and automatic control, wherein, in the charging process of the batteries in series, the auxiliary charging power supply device supplements the charging current of the battery with larger capacity, and in the discharging process, it supplements the discharging current of the battery with smaller capacity. This auxiliary charging power supply device is composed of a high-frequency switching power supply device, and a control program provided by the present invention is installed in the memory. While the microprocessor executes the control program for precise control to minimize power loss, it automatically controls according to the charging and discharging formula and / or charging and discharging curve according to the present invention to perform charging and discharging.

[0028] Another technical solution of the present invention is to provide an uninterrupted current and automatically controlled series charging and discharging method and device, which is configured to periodically and automatically perform precise calibration on the current sensor of the charging and discharging power supply device under predetermined conditions according to the high-specification current sensor of the main charging and discharging power supply device during the charging and discharging operation, and the main charging and discharging power supply device is configured to exchange charging and discharging data with a microprocessor for controlling a single battery cell installed with a control program according to the present invention while accurately identifying the output voltage and current, thereby performing charging and discharging, and it is also configured to identify it as an error in the series charging and discharging circuit when the difference between the sum of the voltage values ​​of the single battery cells and the output voltage of the main charging and discharging power supply device is identified as being greater than a preset value.

[0029] Another technical solution of the present invention is to provide an uninterrupted current and automatically controlled series charging and discharging method and device, which has a means, wherein, ideally, the output voltage of the main charging and discharging power supply device should be the same as the sum of the voltages of the single batteries, or similar to the voltage drop at the contact part (each single battery is usually equal to or less than a few mV), but if the battery contact part or the contact of the relay is poor, and these voltage differences are detected to be greater than the set (predetermined) value, the means generates and notifies a warning message to stop the operation of the equipment and take safety precautions.

[0030] Another technical solution of the present invention is to provide a series charging and discharging method and device with uninterrupted current and automatic control, wherein the number of secondary batteries handled by the charging and discharging device is usually very large (the number of batteries exceeds tens of thousands), so it is not easy to modify or upgrade the operating program of the control device, but according to the present invention, the program of the controller (a few tens of the number of batteries) of the main charging and discharging power supply device used to control the series charging and discharging device can be conveniently modified or upgraded through remote communication (such as Ethernet).

[0031] Beneficial Effects

[0032] The present invention has the following beneficial effects: when a main charge and discharge power supply device is used to charge and discharge a plurality of secondary batteries in series, the equipment cost is reduced due to the simplification of the equipment, and since the operating voltage of the main charge and discharge device is higher than the voltage of a battery by a multiple of the number of batteries, the power conversion efficiency is improved and the operating cost is reduced.

[0033] The present invention has another beneficial effect as follows: as an improvement factor required for conventional series charging and discharging devices, it can solve the concerns about main charging and discharging current interruption (on / off) caused by relay switch interruption and the resulting voltage and current measurement errors.

[0034] The present invention has another beneficial effect as follows: in the charging and discharging process of multiple secondary batteries connected in series, before the charging and discharging cycles of all batteries are completed, there is no current separation between the batteries caused by the relay switch, so the main charging and discharging current is not interrupted, and the output voltage of the main charging and discharging power supply device changes little, so that the main charging and discharging power supply device can only be operated when the operating efficiency is high, thereby improving the power conversion efficiency and reducing the operating cost.

[0035] The present invention has another beneficial effect as follows: the microprocessor is configured to perform precise control by installing a control program designed to control the charge and discharge recipe and / or charge and discharge curve provided by the present invention, thereby minimizing power loss and automatically controlling charge and discharge.

[0036] The present invention has another beneficial effect as follows: due to the series charging and discharging method of connecting multiple secondary batteries in series, the general specification current sensor of a single battery can be automatically calibrated regularly according to the high specification current sensor of the main charging and discharging power supply device, thereby reducing manufacturing costs.

[0037] Since the gain value change, offset value and drift value of the general specification current sensor of a single battery caused by long-term operation are regularly and accurately corrected according to the high specification current sensor, the low-cost general specification current sensor can exhibit the same or similar characteristics as the high specification current sensor.

[0038] The present invention has another beneficial effect as follows: since a function of comparing the output voltage of the main charge-discharge power supply device and the total voltage of a single battery cell in real time is added, it is possible to confirm in real time whether the contact parts including the single battery cell are abnormal, and compared with the existing method of judging the heating state, it is possible to improve the safety of the charge-discharge power supply device, and identify in real time the potential difference that is expected to generate heat, thereby preventing accidents in advance.

[0039] The present invention has another beneficial effect as follows: when the control program of the charging and discharging device is to be modified or upgraded, there is no need to modify or upgrade the program of the charging and discharging controller of a single battery. Instead, it is only necessary to modify or upgrade the controller of the main charging and discharging power supply device, which is far less than the number of batteries, through remote communication, thereby greatly improving the ease of subsequent management of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A series charging and discharging device with uninterrupted current according to the present invention is shown.

[0041] Figure 2 A graph showing the charge and discharge characteristics of a conventional secondary battery is shown.

[0042] Figure 3 A graph showing charging characteristics of secondary batteries having different capacities according to the present invention is shown.

[0043] Figure 4 A graph showing discharge characteristics of secondary batteries having different capacities according to the present invention is shown.

[0044] [Description of Reference Numerals]

[0045] ①: DC power grid ②: Bidirectional main charging and discharging power supply device

[0046] ③: Bidirectional connection relay ④: Bypass relay

[0047] ⑤: Positive grip ⑥: Single battery

[0048] ⑦: Current sensor ⑧: Negative pole grip

[0049] ⑨: Battery voltage ⑩: Current signal

[0050] Battery Controller Predetermined current

[0051] Auxiliary charging power supply unit External power supply

[0052] (16): Two-way communication

[0053] 51: Initial voltage of the battery 52: Maximum voltage

[0054] 53: Predetermined constant current in the battery before charging 54: Predetermined cut-off current

[0055] 55: Constant current 56: Cut-off voltage

[0056] 65: Insufficient current

[0057] 75: According to the battery current mode 76: According to the battery current mode DETAILED DESCRIPTION

[0058] Best Mode

[0059] The best mode of the present invention is to provide a method and device for serial charging and discharging of multiple secondary batteries with an uninterrupted current, wherein the method and device for serially charging and discharging multiple secondary batteries using a bidirectional main charging and discharging power supply device is configured to correct and eliminate the capacity difference of a single battery by adding an auxiliary charging power supply device in parallel to the single battery, and continuously charge and discharge according to a predetermined charging and discharging formula without interrupting (on / off) the charging and discharging current of the main charging and discharging power supply device.

[0060] In addition, another technical solution of the present invention is to provide a series charging and discharging method and device with uninterrupted current, wherein the electrical input of the auxiliary charging power supply device is composed of a DC grid power supply, that is, the input end of the main charging and discharging power supply device, or is composed of one of separate DC and AC powers, and its output is composed of an insulated unidirectional switch mode DC converter, which outputs the voltage of a single battery, and the auxiliary charging power supply device is composed of a separate controller including a microcontroller, which is configured to increase or decrease the voltage and current of a single battery.

[0061] Specific contents of various modes for carrying out the present invention will be described.

[0062] The present invention is an uninterrupted current series charging and discharging method and device, which is configured to use a bidirectional main charging and discharging power supply device to perform series charging and discharging on multiple secondary batteries.

[0063] In addition, the present invention is an uninterrupted current series charging and discharging device and method, wherein multiple single-cell batteries charged and discharged in series in a bidirectional main charging and discharging power supply device can have different capacities respectively. In order to correct the capacity differences of these single-cell batteries, an auxiliary charging power supply device is added in parallel to each single-cell battery, and it is configured to be precisely controlled so as to be able to supplement (correct) the capacity differences.

[0064] Specific embodiments of the present invention will be described.

[0065] <Example>

[0066] Specific embodiments according to the present invention will be described based on the drawings.

[0067] Figure 1 A series charging and discharging device with uninterrupted current according to the present invention is shown.

[0068] Figure 2 A graph showing the charge and discharge characteristics of a conventional secondary battery is shown.

[0069] Figure 3 A diagram (recipe & curve) showing charging characteristics of secondary batteries having different capacities according to the present invention.

[0070] Figure 4 A discharge characteristic diagram (recipe & curve) of secondary batteries having different capacities according to the present invention is shown.

[0071] The present invention is a method and device for serial charging and discharging of uninterrupted current, which is configured to use a bidirectional main charging and discharging power supply device to perform serial charging and discharging on multiple secondary batteries so that the charging and discharging current of the batteries will not be interrupted (for example, Relay on / off), thereby enabling the operating voltage of the main charging and discharging device to be higher than the voltage of one battery by a multiple of the number of batteries, thereby improving the efficiency of power conversion and reducing equipment cost and operation cost.

[0072] In the specification of the present invention, the expression "steps and / or configurations" means that the present invention for series charging and discharging includes method inventions and device inventions, because the present invention includes a configuration obtained by a microprocessor executing a predetermined hardware configuration and a control program installed in a memory, etc.

[0073] like Figure 2 As shown, a conventional secondary battery performs two modes, ie, constant current and constant voltage charging, in charging, and performs only constant current discharging in discharging.

[0074] The present invention comprises the following steps and / or configurations: Figure 2 Before charging, when the predetermined constant current ( Figure 2 When charging the battery, the initial voltage of the battery ( Figure 2 51) will gradually increase and reach the predetermined maximum voltage ( Figure 2 52) (one example is 4,200mV).

[0075] The present invention comprises the following steps: From this point on, the voltage of the battery is maintained at the maximum voltage ( Figure 2 52), while the charging current gradually decreases, and when the predetermined cut-off current (54) is reached, the charging cycle is completed.

[0076] exist Figure 2 In the discharge process, the discharge current is set at a predetermined constant current ( Figure 2 The battery voltage gradually decreases and reaches the predetermined cut-off voltage ( Figure 2 56) (2,800mV in one example), the discharge cycle is complete.

[0077] Next, based on Figure 1 The uninterrupted current series charging and discharging device according to the present invention is described in detail.

[0078] The present invention uses a bidirectional main charging and discharging power supply device to perform series charging and discharging on multiple secondary batteries, which includes the following configurations and steps: by adding auxiliary charging power supply devices in parallel to the single batteries respectively to correct (or supplement) the capacity difference of the single batteries.

[0079] The present invention is configured to use a bidirectional main charge and discharge power supply device to charge and discharge multiple secondary batteries in series. This configuration has the following beneficial effects: (1) since the charge and discharge device is simplified to one, the equipment space and equipment cost are reduced; (2) since the operating voltage of the main charge and discharge device is higher than the voltage of one battery by a multiple of the number of batteries connected in series, the power conversion efficiency is improved and the operating cost is reduced.

[0080] In addition, the present invention requires the following apparatus and method, which (3) can compensate for the capacity difference between single-cell batteries and (4) can prevent the intermittent (on / off) phenomenon of the charge and discharge current of the battery.

[0081] The auxiliary charging power supply device according to the present invention is used to correct the capacity difference between single-cell batteries, and is composed of an insulating unidirectional DC-DC converter. The insulating unidirectional DC converter takes a DC grid power supply, i.e., the input end of a main charger and discharger, or a separate external power supply as input, and takes the voltage of a single-cell battery as output.

[0082] The auxiliary charging power supply device according to the present invention is configured to supplement the charging current of the battery with a larger capacity during the charging process of the single batteries connected in series, and to supplement the discharging current of the battery with a smaller capacity during the discharging process.

[0083] Furthermore, the auxiliary charging power supply device according to the present invention is preferably composed of a high-frequency switching power supply device, and is configured to have a control program custom-designed for minimizing power loss installed in a memory, and to perform precise control by executing the control program through a microprocessor.

[0084] Reference Figure 1 , a method and apparatus for serial charging and discharging of uninterrupted current according to the present invention will be described.

[0085] In the present invention, a high-voltage DC power supply provided to a series charging and discharging device, i.e., a DC power grid ① which is greater than the sum of the voltages of all connected batteries, is configured to provide a DC within a predetermined voltage range (an example is a minimum of 300 VDC to a maximum of 350 VDC). During the discharge process, if the voltage of the DC power grid exceeds the maximum voltage, the predetermined voltage range is maintained by converting the power into a conventional AC power grid (national power supply grid).

[0086] The bidirectional main charge and discharge power supply device ② is configured according to the charge and discharge formula (refer to Figure 2 ) uses a current source to perform charge and discharge functions on the following multiple secondary batteries connected in series.

[0087] The single battery ⑥ is connected or separated through the two-way connection relay ③ and the bypass relay ④ to be connected to the main circuit. In the conventional method (existing method), at this time, the interruption (on / off) of the main current occurs due to the relay.

[0088] At the moment when the relay element operates, the current of the main charging and discharging power supply device is interrupted (on / off), and the measurement of current and voltage may be erroneous.

[0089] The battery voltage is detected by connecting the positive and negative grips ⑤ and ⑧ of the battery, and the current signal ⑩ actually flowing to the battery ⑥ is detected by the series current sensor ⑦ and provided as an input signal to the battery controller controlled by the microprocessor

[0090] Battery Controller The device is configured to exchange charge and discharge information through a host controller and bidirectional communication (16), and simultaneously execute a charge and discharge control program according to the present invention installed in a memory through a microprocessor to interoperate with each other, thereby performing precise control.

[0091] Auxiliary charging power supply device according to the present invention From a separate external power supply For power supply, you can use the power of the DC power grid① or a separate AC power supply.

[0092] Auxiliary charging power supply unit According to the control of the battery controller, the single battery ⑥ is supplemented with a predetermined current Thereby making it charge and discharge according to the charge and discharge formula.

[0093] Compared with one battery connection (parallel connection), since the battery connection device of the present invention connects the required number of charge and discharge batteries in series, that is, connects them in series, the voltage is as high as the number of batteries, so the power conversion efficiency is high, resulting in reduced operating costs. In addition, since a bidirectional main charge and discharge power supply device ② is used for charging and discharging, the charge and discharge circuit is simplified, thereby reducing equipment costs.

[0094] Next, based on Figure 3 A graph describing the charging characteristics of secondary batteries with different capacities.

[0095] The present invention comprises the following steps or configurations: Figure 2 During the charging cycle, a main charging and discharging power supply unit ( Figure 1 ②) Charge batteries with different capacities in series, but use the battery with the smallest capacity. Figure 3 Current mode ( Figure 3 75) for charging.

[0096] The present invention includes the following steps or configurations: At this time, the battery with a larger capacity has not yet reached the maximum voltage ( Figure 3 52), so through the auxiliary charging power supply device ( Figure 1 of ) supplies insufficient current ( Figure 3 65) for additional charging.

[0097] The present invention includes the following steps or configurations: when the charging of the "smallest capacity battery" is completed, the main charging power supply device stops the charging function, and for the battery with a larger capacity, the battery controller ( Figure 1 of ) can complete the charging cycle through an auxiliary charging power supply device.

[0098] Through this process, all batteries connected in series in the method and device for series charging and discharging according to the present invention can complete the charging cycle under the condition of uninterrupted charging current.

[0099] Next, based on Figure 4 A graph depicting the discharge characteristics of secondary batteries with different capacities.

[0100] The present invention comprises the following steps or configurations: Figure 2 During the charging cycle, a main charging and discharging power supply unit ( Figure 1 ②) The batteries with different capacities are discharged in series, but the battery with the largest capacity is used. Figure 4 Current mode ( Figure 3 76) for discharge.

[0101] The present invention includes the following steps or configurations: At this time, the battery with the smallest capacity reaches the cut-off voltage first ( Figure 4 56), from this point on, the auxiliary charging power supply device corresponding to the battery ( Figure 1 middle ) produces a current as large as the main discharge current ( Figure 4 59) and sent to the main discharge circuit.

[0102] That is, since the current corresponding to the battery becomes "0", it is as if the discharge has been completed.

[0103] When the "largest capacity battery" reaches the cut-off voltage ( Figure 4 56), all batteries complete the discharge cycle with uninterrupted current.

[0104] The auxiliary charging power supply device supplements the charging current of the battery with a larger capacity during the charging process of the batteries connected in series, and supplements the discharging current of the battery with a smaller capacity during the discharging process.

[0105] This auxiliary charging power supply device is composed of a high-frequency switching power supply device, and is configured to have the control program provided by the present invention installed in its memory. While the microprocessor executes the control program for precise control to minimize power loss, it automatically controls according to the charge and discharge formula and / or charge and discharge curve according to the present invention to perform charge and discharge operations.

[0106] The present invention includes the following steps or configurations: in the charge and discharge operation, under predetermined conditions, the current sensor of the main charge and discharge power supply device is calibrated automatically and regularly based on the high specification current sensor (with high accuracy) of the main charge and discharge power supply device.

[0107] More specifically, since the current sensor of the general specification of the single battery can be regularly and automatically calibrated according to the high specification current sensor of the main charge and discharge power supply device, a large number of high specification current sensors can be reduced, thereby reducing manufacturing costs.

[0108] The present invention includes the following steps or configurations: the main charging and discharging power supply device exchanges the data required for charging and discharging with a microprocessor for controlling a single battery cell installed with a control program according to the present invention while accurately identifying the output voltage and current of the single battery cell connected in series, thereby performing charging and discharging.

[0109] The present invention includes the following steps or configurations: when the difference between the sum of the voltage values ​​of the single cells and the output voltage of the main charge and discharge power supply device is identified as being greater than or equal to a set (predetermined) value, it is identified as an error in the series charge and discharge circuit.

[0110] The present invention includes the following steps or configurations: ideally, the output voltage of the main charging and discharging power supply device should be the same as the sum of the voltages of the single-cell batteries connected in series, or similar to the voltage drop at the contact part (a single-cell battery is usually equal to or less than a few mV), but if the contact of the battery contact part or the relay is poor, and these voltage differences are detected to be greater than or equal to the set (predetermined) value, it is judged that an error has occurred in the charging and discharging circuit, and a warning message is generated and notified so as to stop the operation of the equipment and take safety precautions.

[0111] The number of batteries handled by the secondary battery charging and discharging device is usually very large (more than tens of thousands of batteries), so it is not easy to modify or upgrade the charging and discharging control program of the control device.

[0112] However, since the present invention includes the following steps or configurations, it has an advantageous effect: the program of the controller (a few tens of the number of batteries) of the main charging and discharging power supply device for controlling the series charging and discharging device can be easily modified or upgraded through remote communication (such as Ethernet).

[0113] The "preset current curve", "charging formula" and "discharging formula" in the present specification are as follows: Figure 2 , Figure 3 and Figure 4 As shown and described in the accompanying drawings, this control is performed by a battery controller ( Figure 1 of ) and the upper controller execute the charge and discharge control program customized and designed according to the present invention installed in the memory to interact with each other, thereby performing precise control.

[0114] Next, configurations according to various embodiments of the present invention will be described.

[0115] As an embodiment of the present invention, the following steps or configurations are included: for a device and method for charging and discharging using a bidirectional main charge and discharge power supply device, a plurality of secondary batteries are charged and discharged in series using a bidirectional main charge and discharge power supply device, which is configured to correct the capacity difference of a single battery by adding an auxiliary charging power supply device in parallel to the single battery, and continuously charge and discharge according to a predetermined formula (electrical conditions for charging and discharging, etc.) without interrupting (on / off) the charge and discharge current of the main charge and discharge power supply device.

[0116] As another embodiment of the present invention, the following steps or configurations are included: the electrical input of the auxiliary charging power supply device is composed of a DC grid power supply, that is, the input end of the main charging and discharging power supply device, or is composed of one of separate DC and AC powers, and its output is composed of an isolated unidirectional switch mode DC converter, which outputs the voltage of a single battery, and the auxiliary charging power supply device is composed of a separate battery controller including a microcontroller installed with a control program, which is configured to increase or decrease the voltage and current of a single battery.

[0117] As another embodiment of the present invention, in series charging, when the main charge and discharge power supply device is charged at a predetermined constant current according to a predetermined charging recipe, the voltage of the "battery with the smallest capacity" first reaches the predetermined set voltage (or maximum voltage, such as 4,200mV for lithium batteries).

[0118] The present invention includes the following steps or configurations: the main charging and discharging power supply device performs constant voltage charging (charging current according to a predetermined formula) according to the "battery with the smallest capacity", and other batteries with larger capacities use the auxiliary charging power supply device to supplement insufficient charging current according to a predetermined charging formula, so that all single-cell batteries can be charged according to the predetermined charging formula without interrupting (on / off) current.

[0119] As another embodiment of the present invention, in series discharge, when the main charge and discharge power supply device discharges at a predetermined constant current based on the "battery with the largest capacity" according to a predetermined discharge recipe in the discharge cycle, the voltage of the "battery with the smallest capacity" first reaches the predetermined set voltage (or cut-off voltage, 2,800mV for lithium batteries).

[0120] The present invention includes the following steps or configurations: the auxiliary charging power supply device of the "battery with the smallest capacity" supplies a current (the current of the corresponding battery is "0") that is the same as the current of the main charging and discharging power supply device (the current of the discharge formula), each battery performs the discharge operation according to the capacity difference, and all batteries complete the discharge according to the predetermined discharge formula without interrupting (on / off) current.

[0121] As another embodiment of the present invention, the following steps or configurations are included: during charging, the main charging and discharging power supply device only charges in a predetermined constant current charging interval, and in a constant voltage charging interval, the auxiliary charging power supply device of the single battery controls the charging current according to a predetermined charging formula.

[0122] As another embodiment of the present invention, the following steps or configurations are included: while using a main charge and discharge power supply device with relatively better power conversion efficiency than an auxiliary charge power supply device of a single-cell battery, in order to simplify the control function, during charging, the main charge and discharge power supply device is charged with a predetermined constant current in a predetermined constant current charging interval, and in a constant voltage charging interval, it is charged according to a preset current curve, and a current less than the set current in the charging formula is used to supplement the charging current in the auxiliary charge power supply device of the single-cell battery according to a predetermined charging formula.

[0123] Based on the above technical configuration, those skilled in the art can easily describe various protection scopes of a series charging and discharging method and device for uninterrupted current.

[0124] First, the protection scope of the present invention for a series charging and discharging method with uninterrupted current will be described.

[0125] As another embodiment of the present invention, the following steps are included: for a series charging and discharging method using an uninterrupted current of a bidirectional main charging and discharging power supply device, a bidirectional main charging and discharging power supply device is used to charge and discharge multiple secondary batteries in series, wherein the charging and discharging are continuously performed according to a predetermined formula without interrupting the charging and discharging current of the main charging and discharging power supply device.

[0126] As another embodiment of the present invention, the following steps are included: an auxiliary charging power supply device is provided in parallel with the single batteries connected in series, so as to correct the capacity difference of the secondary batteries connected in series.

[0127] As another embodiment of the present invention, the following steps are included: the electrical input of the auxiliary charging power supply device is composed of a DC grid power supply, that is, the input end of the main charging and discharging power supply device, or is composed of one of separate DC and AC powers, and its output is composed of an insulated unidirectional switch mode DC converter, which uses the voltage of a single battery as output, thereby correcting the capacity differences of multiple secondary batteries connected in series.

[0128] As another embodiment of the present invention, the following steps are included: in the series charging and discharging method, a control program is installed in the auxiliary charging power supply device, and the voltage and current of a single battery cell are increased and decreased by using each battery controller, and the battery controller is configured to control the charging and discharging of each single battery cell by executing the control program in a microcontroller.

[0129] As another embodiment of the present invention, in series charging, when the main charging and discharging power supply device is charged with a predetermined constant current according to a predetermined charging formula, among the batteries in series, the voltage of the battery with the smallest capacity reaches the predetermined set voltage first, and the series charging and discharging includes the following steps: the charging and discharging power supply device performs constant voltage charging according to the battery with the smallest capacity.

[0130] As another embodiment of the present invention, the following steps are included: in the series charging and discharging method, the battery with a larger capacity than the battery with the smallest capacity uses the auxiliary charging power supply device to supplement the insufficient charging current according to a predetermined charging formula, so that all single-cell batteries can be charged under uninterrupted current.

[0131] As another embodiment of the present invention, the following steps are included: in the series discharge, the main charge and discharge power supply device discharges at a predetermined constant current based on the battery with the largest capacity among the multiple batteries connected in series according to a predetermined discharge recipe in the discharge cycle.

[0132] As another embodiment of the present invention, the following steps are included: among a plurality of batteries connected in series, the voltage of the battery with the smallest capacity reaches a predetermined set voltage first, and the auxiliary charging power supply device of the battery with the smallest capacity supplies a current as large as that of the main charging and discharging power supply device.

[0133] As another embodiment of the present invention, the following steps are included: a plurality of batteries connected in series repeat the above actions in sequence according to the size of the capacity, and all the batteries complete the discharge according to the set (predetermined) discharge formula under the condition of uninterrupted current.

[0134] As another embodiment of the present invention, the following steps are included: during charging, the main charging and discharging power supply device charges the battery with the smallest capacity only in a predetermined constant current charging interval, and in a constant voltage charging interval, the auxiliary charging power supply device of the single battery controls the charging current according to a predetermined charging formula.

[0135] As another embodiment of the present invention, the following steps are included: while using a main charging and discharging power supply device with relatively better power conversion efficiency than an auxiliary charging power supply device of a single battery, in order to simplify the control function, during charging, the main charging and discharging power supply device charges with a predetermined constant current based on the battery with the smallest capacity in a predetermined constant current charging interval.

[0136] As another embodiment of the present invention, the following steps are included: in the constant voltage charging interval, charging is performed according to a preset current curve, and the current that is less than the set current in the charging formula is used to supplement the charging current in the auxiliary charging power supply device of the single battery according to the predetermined charging formula.

[0137] As another embodiment of the present invention, the following steps are included: the current sensor of the auxiliary charging power supply device and the current sensor of the main charging and discharging power supply device are automatically or periodically calibrated while exchanging measurement values ​​with each other, thereby measuring the current of a single battery and accurately correcting the capacity difference of multiple secondary batteries connected in series.

[0138] As another embodiment of the present invention, the following steps are included: comparing the output voltage of the main charging and discharging power supply device with the sum of the voltages of a single battery cell; if the voltage drop caused by the contact resistance has a voltage difference greater than or equal to a set value, then in order to improve safety, it is identified in advance as a defective battery or contact part, and the operation is stopped or a warning message is sent to take preventive measures.

[0139] As another embodiment of the present invention, the following steps are included: in a serial charging and discharging method for connecting a plurality of secondary batteries in series without interrupting the current flow, the charging and discharging program of a single main charger and discharger controller is easily modified or upgraded through remote communication.

[0140] Next, the protection scope of the present invention for a series charging and discharging device with uninterrupted current will be described.

[0141] For a series charging and discharging device using an uninterrupted current of a bidirectional main charging and discharging power supply device, a bidirectional main charging and discharging power supply device is used to charge and discharge multiple secondary batteries in series, wherein charging and discharging are continuously performed according to a predetermined formula without interrupting the charging and discharging current of the main charging and discharging power supply device.

[0142] In another embodiment of the present invention, an auxiliary charging power supply device is provided in parallel with the single battery connected in series, so as to correct the capacity difference of the plurality of secondary batteries connected in series.

[0143] As another embodiment of the present invention, the electrical input of the auxiliary charging power supply device consists of a DC grid power supply, i.e., the input terminal of the main charging and discharging power supply device, or consists of one of separate DC and AC powers, and its output consists of an isolated unidirectional switch mode DC converter, which outputs the voltage of a single battery.

[0144] As another embodiment of the present invention, a control program is installed in the auxiliary charging power supply device, and the voltage and current of a single battery cell are increased and decreased by using each battery controller, and the battery controller is configured to control the charging and discharging of each single battery cell by executing the control program in a microcontroller.

[0145] As another embodiment of the present invention, in series charging, when the main charge and discharge power supply device is charged with a predetermined constant current according to a predetermined charging recipe, among the batteries in series, the voltage of the battery with the smallest capacity reaches the predetermined set voltage first, and the charge and discharge power supply device is configured to perform constant voltage charging according to the battery with the smallest capacity.

[0146] As another embodiment of the present invention, a battery with a larger capacity than the battery with the smallest capacity uses the auxiliary charging power supply device to supplement the insufficient charging current according to a predetermined charging formula, so that all single-cell batteries can be charged without interrupting the current.

[0147] As another embodiment of the present invention, in series discharge, the main charging and discharging power supply device is configured to discharge at a predetermined constant current according to a predetermined discharge recipe based on the battery with the largest capacity among the multiple batteries connected in series in the discharge cycle, and among the multiple batteries connected in series, the voltage of the battery with the smallest capacity reaches the predetermined set voltage first, and the auxiliary charging power supply device of the battery with the smallest capacity is configured to supply a current as large as that of the main charging and discharging power supply device.

[0148] As another embodiment of the present invention, a plurality of batteries connected in series repeat the above-mentioned actions in sequence according to the sizes of the capacities, and all the batteries complete the discharge according to the predetermined discharge formula under the condition of uninterrupted current.

[0149] As another embodiment of the present invention, during charging, the main charge and discharge power supply device only charges in a predetermined constant current charging interval, and in a constant voltage charging interval, the auxiliary charging power supply device of the single battery controls the charging current according to a predetermined charging recipe.

[0150] As another embodiment of the present invention, while using a main charging and discharging power supply device with better power conversion efficiency than an auxiliary charging power supply device of a single battery, in order to simplify the control function, during charging, the main charging and discharging power supply device is configured to charge with a predetermined constant current in a predetermined constant current charging interval.

[0151] As another embodiment of the present invention, in the constant voltage charging interval, charging is performed according to a preset current curve, and the current less than the set current in the charging formula is supplemented and controlled in the auxiliary charging power supply device of the single battery according to the predetermined charging formula.

[0152] As another embodiment of the present invention, the current sensor of the auxiliary charging power supply device and the current sensor of the main charging and discharging power supply device are automatically or periodically calibrated while exchanging measurement values ​​with each other, thereby measuring the current of a single battery and accurately correcting the capacity differences of multiple secondary batteries connected in series.

[0153] As another embodiment of the present invention, the output voltage of the main charging and discharging power supply device and the total voltage of a single battery are compared. If the voltage drop caused by the contact resistance has a voltage difference greater than or equal to a set value, in order to improve safety, it is identified in advance as a defective battery or contact part, so that operation can be stopped or preventive measures can be taken.

[0154] As another embodiment of the present invention, in a serial charging and discharging method for connecting a plurality of secondary batteries in series without interrupting current flow, the charging and discharging program of a single main charger and discharger controller can be easily modified or upgraded through remote communication.

[0155] The protection scope of the present invention may be determined in various ways based on the above content in addition to the protection scope described above as needed.

[0156] Industrial Applicability

[0157] The present invention provides a method and device for serial charging and discharging of multiple secondary batteries with an uninterrupted current, wherein the method and device for serially charging and discharging multiple secondary batteries using a bidirectional main charging and discharging power supply device is configured to correct and eliminate the capacity difference of a single battery by adding an auxiliary charging power supply device in parallel to a single battery, and continuously charge and discharge according to a predetermined formula without interrupting (on / off) the charging and discharging current of the main charging and discharging power supply device, thereby reducing equipment costs and operating costs, and therefore the industrial practicability is very high.

Claims

1. A series charging and discharging device with uninterrupted current, characterized in that: For a series charging and discharging device with an uninterrupted current using a bidirectional main charging and discharging power supply device, The bidirectional main charge-discharge power supply device is used to charge and discharge a plurality of secondary batteries connected in series, wherein: Without interrupting the charging and discharging current of the bidirectional main charging and discharging power supply device, charging and discharging are continuously performed according to a predetermined formula, In order to correct the capacity difference of multiple secondary batteries connected in series, an auxiliary charging power supply device is added in parallel to the multiple single-cell batteries connected in series. The electrical input of the auxiliary charging power supply device is composed of a DC grid power supply, that is, the input end of the bidirectional main charging and discharging power supply device, or is composed of one of a separate DC and AC power, Its output is composed of an insulated unidirectional switch mode DC converter, which uses the voltage of each single battery as output. In the charging process of the plurality of secondary batteries connected in series, the auxiliary charging power supply device supplements the charging current of the battery with a larger capacity, and in the discharging process of the plurality of secondary batteries connected in series, the auxiliary charging power supply device supplements the discharging current of the battery with a smaller capacity, Wherein, in the series charging, when the bidirectional main charge-discharge power supply device is charged with a predetermined constant current according to a predetermined charging formula, the voltage of the battery with the smallest capacity among the multiple batteries connected in series first reaches the predetermined set voltage, and the main charge-discharge power supply device is configured to perform constant voltage charging according to the battery with the smallest capacity, The other batteries with larger capacity than the smallest battery use the auxiliary charging power supply device to supplement the insufficient charging current according to the predetermined charging formula, so that all single batteries can be charged without interrupting the current. In the series discharge, the bidirectional main charge-discharge power supply device is configured to discharge the battery with the largest capacity among the multiple batteries connected in series at the predetermined constant current according to a predetermined discharge recipe in the discharge cycle, Among the multiple batteries connected in series, the auxiliary charging power supply device of the battery with the smallest capacity supplies a current as large as the current of the bidirectional main charging and discharging power supply device.

2. The uninterrupted current series charging and discharging device according to claim 1, characterized in that: A control program is installed in the auxiliary charging power supply device, and the voltage and current of each of the single cells are increased and decreased by using each battery controller, and the battery controller is configured to control the charging and discharging of each of the single cells by executing the control program in a microcontroller.

3. The uninterrupted current series charging and discharging device according to claim 1, characterized in that: The multiple batteries connected in series repeat the discharge operation in the series discharge in sequence according to the size of the capacity, and all the batteries complete the discharge according to the predetermined discharge formula under the condition of uninterrupted current.

4. The uninterrupted current series charging and discharging device according to claim 1, characterized in that: During charging, the bidirectional main charge-discharge power supply device charges the battery with the smallest capacity only in a predetermined constant current charging interval, and in a constant voltage charging interval, the auxiliary charging power supply device of the single battery controls the charging current according to the predetermined charging formula.

5. The uninterrupted current series charging and discharging device according to claim 1, characterized in that: While using the bidirectional main charge-discharge power supply device with relatively better power conversion efficiency than the auxiliary charging power supply device of the single battery, in order to simplify the control function, During charging, the bidirectional main charge-discharge power supply device charges the battery with the smallest capacity at the predetermined constant current in a predetermined constant current charging interval. In the constant voltage charging range, charging is performed according to the preset current curve. The current that is less than the set current in the charging formula is used to supplement the charging current in the auxiliary charging power supply device of the single battery according to the predetermined charging formula.

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