Battery unit, control device, and control method

Abstract

To reduce the occurrence of voltage dispersion of battery cells.SOLUTION: A storage battery unit comprises a plurality of chargeable / dischargeable battery cells, measurement circuits each of which is connected with each of the plurality of battery cells to measure the state of the battery cells, a current adjustment part which adjusts internal consumption current generated by each of the plurality of battery cells and including current flowing through each of the measurement circuits, and an adjustment control unit which controls the current adjustment part so that the current values are equal to each other among the battery cells based on a current value of each of the internal consumption current.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a storage battery unit, a control device, and a control method.

Background Art

[0002] In recent years, storage battery units in which a plurality of battery cells are connected have been known (see, for example, Patent Document 1). A conventional storage battery unit as described above includes a cell balance circuit that adjusts the voltages of a plurality of battery cells.

Prior Art Literature

Patent Literature

[0003]

Patent Document 1

Summary of the Invention

Problem to be Solved by the Invention

[0004] However, in a conventional storage battery unit as described above, for example, when the storage battery unit incorporates a measurement circuit that measures the voltage of a battery cell, voltage variation among the battery cells occurs due to variation in the measurement circuit. That is, although the conventional storage battery unit as described above can adjust the voltage variation that has occurred in the battery cells, it has been difficult to reduce the occurrence of voltage variation among the battery cells caused by variation in the measurement circuit, for example.

[0005] The present invention has been made to solve the above problem, and an object of the present invention is to provide a storage battery unit, a control device, and a control method that can reduce the occurrence of voltage variation among battery cells.

Means for Solving the Problem

[0006] To solve the above problems, one aspect of the present invention is a battery storage unit characterized by comprising: a plurality of battery cells, each containing a predetermined number of basic battery cells, which are chargeable and dischargeable; a measurement circuit connected to each of the plurality of battery cells for measuring the state of the battery cells; a current adjustment unit for adjusting the internal consumption current of each of the plurality of battery cells, which includes the current flowing through each of the measurement circuits; and an adjustment control unit that controls the current adjustment unit based on the current value of each of the internal consumption currents so that the current values ​​match among the battery cells.

[0007] Furthermore, in one aspect of the present invention, the above-described storage battery unit is provided with a current detection unit for detecting each of the internal current consumptions, and the adjustment control unit controls the current adjustment unit based on the current value of each of the internal current consumptions detected by the current detection unit, so that the current values ​​match among the respective battery cells.

[0008] Furthermore, in one aspect of the present invention, the above-described storage battery unit is characterized in that the current adjustment unit includes an adjustment resistor that allows a predetermined current to flow from each of the plurality of battery cells, and the adjustment control unit adjusts the current consumed by the battery cells by flowing the current from the battery cells through the adjustment resistor.

[0009] Furthermore, in one aspect of the present invention, the battery unit described above is characterized in that the current adjustment unit includes a switch unit connected in series with the adjustment resistor, and the adjustment control unit adjusts the current consumed by the battery cell by controlling the conduction of the switch unit by pulse width modulation.

[0010] Furthermore, in one aspect of the present invention, the battery unit described above is characterized in that the switch portion is a photocoupler.

[0011] Furthermore, in one aspect of the present invention, the adjustment control unit controls the current adjustment unit so that the maximum value of the current value matches the other current values ​​in the above-described battery unit.

[0012] Furthermore, one aspect of the present invention is a control device for a storage battery unit comprising a plurality of chargeable and dischargeable battery cells, each of which contains a predetermined number of basic battery cells, and a measurement circuit connected to each of the plurality of battery cells for measuring the state of the battery cells, the control device comprising a current adjustment unit for adjusting the internal consumption current of each of the plurality of battery cells, which includes the current flowing through each of the measurement circuits, and an adjustment control unit for controlling the current adjustment unit based on the current value of each of the internal consumption currents so that the current values ​​match among the respective battery cells.

[0013] Furthermore, one aspect of the present invention is a control method for a storage battery unit comprising: a plurality of chargeable and dischargeable battery cells, each containing a predetermined number of basic battery cells; a measurement circuit connected to each of the plurality of battery cells for measuring the state of the battery cells; and a current adjustment unit for adjusting the internal consumption current of each of the plurality of battery cells, which includes the current flowing through each of the measurement circuits, wherein the adjustment control unit includes an adjustment control step in which the adjustment control unit controls the current adjustment unit based on the current value of each of the internal consumption currents so that the current values ​​match among the respective battery cells. [Effects of the Invention]

[0014] According to the present invention, it is possible to reduce the occurrence of voltage variations in battery cells. [Brief explanation of the drawing]

[0015] [Figure 1] This is a block diagram showing an example of a battery storage unit according to this embodiment. [Figure 2]It is a block diagram showing a configuration example of the control device according to the present embodiment. [Figure 3] It is a flowchart showing an example of the operation of the storage battery unit according to the present embodiment. [Figure 4] It is a block diagram showing a configuration example of the control device according to a first modification of the present embodiment. [Figure 5] It is a block diagram showing a configuration example of the control device according to a second modification of the present embodiment. MODE FOR CARRYING OUT THE INVENTION

[0016] Hereinafter, a storage battery unit, a control device, and a control method according to an embodiment of the present invention will be described with reference to the drawings.

[0017] Figure 1 is a block diagram showing an example of the storage battery unit 1 according to the present embodiment. As shown in Figure 1, the storage battery unit 1 includes a control device 10 and a battery module 20.

[0018] The battery module 20 is, for example, a module mounted with a storage battery or a substrate, and includes a plurality of battery cells 21 (21-1, 21-2, 21-3, 21-4, ...). In the present embodiment, each of the battery cell 21-1, the battery cell 21-2, the battery cell 21-3, and the battery cell 21-4 has the same configuration. When referring to any battery cell included in the storage battery unit 1, or when no particular distinction is made, the battery cell will be described as the battery cell 21.

[0019] Further, each of the plurality of battery cells 21 includes a predetermined number of basic battery cells. The basic battery cell is, for example, a battery cell of a basic unit or a minimum unit, and the battery cell 21 may include a plurality of basic battery cells connected in series or in parallel. In the present embodiment, as an example, an example in which the battery cell 21 includes one basic battery cell will be described.

[0020] In the battery module 20, the plurality of battery cells 21 are connected in series between the power supply line L1 and the power supply line L2. Here, the power supply line L1 is the positive electrode power supply line (positive electrode power line) of the storage battery unit 1. The power supply line L2 is the negative electrode power supply line (negative electrode power line) of the storage battery unit 1.

[0021] The battery cells 21 are, for example, storage batteries such as lithium batteries and lead-acid batteries, and are capable of charging and discharging DC power. A measurement circuit 11, a current detection unit 12, and a current adjustment unit 13, which will be described later, are connected to each battery cell 21. Each battery cell 21 constantly consumes internal current consumed by the connected measurement circuit 11, current detection unit 12, and current adjustment unit 13.

[0022] The control device 10 is, for example, a control box, a control board, or the like, and controls the storage battery unit 1. The control device 10 includes a plurality of measurement circuits 11 (11-1, 11-2, 11-3, 11-4, ...), a plurality of current detection units 12 (12-1, 12-2, 12-3, 12-4, ...), a plurality of current adjustment units 13 (13-1, 13-2, 13-3, 13-4, ...), a storage unit 14, and a control unit 15.

[0023] Note that in the present embodiment, each of the measurement circuit 11-1, measurement circuit 11-2, measurement circuit 11-3, and measurement circuit 11-4 has the same configuration. When referring to any measurement circuit included in the storage battery unit 1, or when no particular distinction is made, the measurement circuit 11 will be used for description.

[0024] Furthermore, in the present embodiment, each of the current detection unit 12-1, current detection unit 12-2, current detection unit 12-3, and current detection unit 12-4 has the same configuration. When referring to any current detection unit included in the storage battery unit 1, or when no particular distinction is made, the current detection unit 12 will be used for description.

[0025] Furthermore, in this embodiment, current adjustment units 13-1, 13-2, 13-3, and 13-4 each have the same configuration, and when referring to any current adjustment unit provided in the battery unit 1, or when not specifically distinguishing between them, they will be described as current adjustment unit 13.

[0026] The measurement circuit 11 is connected to each of the multiple battery cells 21 and measures the state of the battery cells 21. For example, the measurement circuit 11 is connected one-to-one with a battery cell 21 and measures the voltage (output voltage) of the battery cell 21. The measurement circuit 11 receives power from the connected battery cell 21 and constantly consumes a predetermined current as the internal current of the battery cell 21. Furthermore, there is variation in the current consumption of each measurement circuit 11, and the current consumption changes over time due to factors such as the deterioration of circuit elements. Furthermore, the measurement circuit 11 includes a voltage detection unit 111.

[0027] The voltage detection unit 111 is connected between the positive electrode (+ electrode) and the negative electrode (- electrode) of the battery cell 21. The voltage detection unit 111 is, for example, a voltmeter, an AFE (Analog Front End) or other measurement IC (Integrated Circuit), an ADC (Analog to Digital Converter), etc., and detects the output voltage of the battery cell 21.

[0028] The current detection unit 12 is positioned, for example, on the power line of the positive electrode of the battery cell 21. The current detection unit 12 is, for example, an ammeter, a Hall element, or a shunt resistor, and detects the current consumed by the battery cell 21. That is, the current detection unit 12 detects the internal consumption current of each battery cell 21, which includes the current flowing through each measurement circuit 11.

[0029] The current adjustment unit 13 is connected, for example, to each measurement circuit 11 and adjusts the internal current consumption of each of the multiple battery cells 21. The current adjustment unit 13 is connected one-to-one with the measurement circuit 11. The detailed configuration of the current adjustment unit 13 will be described later with reference to Figure 2.

[0030] The memory unit 14 stores various types of information used by the control device 10 (control unit 15). For example, the memory unit 14 stores measurement data from the measurement circuit 11 (voltage value of the battery cell 21), detected values ​​from the current detection unit 12 (current value of internal consumption current), setting information from the current adjustment unit 13, and so on.

[0031] The control unit 15 is, for example, a processor including a CPU (Central Processing Unit), and comprehensively controls the battery unit 1 (control device 10 and battery module 20). The control unit 15 includes an adjustment control unit 151.

[0032] The adjustment control unit 151 controls the current adjustment unit 13 so that the current values ​​of the internal current consumption of each battery cell 21 are the same, based on the current value of the internal current consumption of each battery cell 21 detected by the current detection unit 12. In order to reduce the variation in the internal current consumption of the battery cells 21 caused by variations in the measurement circuit 11, the adjustment control unit 151 uses the current adjustment unit 13 to adjust the current value of the internal current consumption detected by the current detection unit 12 so that it is the same value among the battery cells 21.

[0033] Now, referring to Figure 2, we will describe the more detailed configuration of the control device 10, focusing on the measurement circuit 11 and current adjustment unit 13 connected to one battery cell. Figure 2 is a block diagram showing an example of the configuration of the control device 10 according to this embodiment.

[0034] As shown in Figure 2, the control device 10 includes a measurement circuit 11 and a current detection unit 12 connected to the battery cell 21, a current adjustment unit 13, a storage unit 14, and a control unit 15. The current adjustment unit 13 comprises an adjustment resistor 131, a photocoupler 132, and a MOS (Metal-Oxide-Semiconductor) transistor 133.

[0035] The adjustment resistor 131 is a resistive element that adjusts the current consumption of the battery cell 21 (measurement circuit 11), and its resistance value is set so that a predetermined current flows from the battery cell 21. In other words, the adjustment resistor 131 is a resistive element that allows a predetermined current to flow from each of the multiple battery cells 21. The adjustment resistor 131 is connected in series with the phototransistor 132B of the photocoupler 132 between the positive electrode (+ electrode) and the negative electrode (- electrode) of the battery cell 21.

[0036] The photocoupler 132 (an example of a switch section) is a switch section that controls the conduction of the adjustment resistor 131 and is connected in series with the adjustment resistor 131. The photocoupler 132 includes a photodiode 132A and a phototransistor 132B.

[0037] The photodiode 132A is connected in series with the MOS transistor 133 between a power line from a different power source than the battery cell 21 (for example, a power supply Vdd for the digital circuit) and a ground power line, and emits light when the MOS transistor 133 is turned on (conductive).

[0038] The phototransistor 132B is connected in series with the adjustment resistor 131 between the positive electrode (+ electrode) and the negative electrode (- electrode) of the battery cell 21, and turns ON (conducts) upon receiving light from the photodiode 132A. When the phototransistor 132B turns ON, it connects the adjustment resistor 131 to the battery cell 21 and causes the adjustment resistor 131 to consume a predetermined current.

[0039] MOS transistor 133 is, for example, an N-channel MOS transistor, and is connected in series with photodiode 132A between the power supply line Vdd and the ground power supply line. The source terminal of MOS transistor 133 is connected to the ground power supply line, the drain terminal is connected to the cathode terminal of photodiode 132A, and the gate terminal (control terminal) is connected to the signal line of the control signal S.

[0040] The MOS transistor 133 turns on when the control signal S output by the control unit 15 is in a high state. Conversely, the MOS transistor 133 turns off (non-conductive) when the control signal S is in a low state. When the MOS transistor 133 turns on, current flows through the photodiode 132A, causing the photodiode 132A to emit light.

[0041] The memory unit 14 includes, for example, a current value memory unit 141 and a current setting memory unit 142. The current value storage unit 141 stores the current value of each internal consumption current detected by each current detection unit 12. The current setting memory unit 142 stores the setting information for each current adjustment unit 13.

[0042] The adjustment control unit 151 of the control unit 15 adjusts the current consumed by the battery cell 21 by, for example, passing the current from the battery cell 21 through the adjustment resistor 131. The adjustment control unit 151 adjusts the current consumed by the battery cell 21 by controlling the conduction of the photocoupler 132 (phototransistor 132B) using pulse width modulation (PWM). The adjustment control unit 151 controls the current adjustment unit 13 so that the current value of the other internal currents matches the maximum current value of the internal current.

[0043] Specifically, the adjustment control unit 151 first acquires the current value of the internal current consumption detected by each current detection unit 12, and stores the acquired current value of the internal current consumption in the current value storage unit 141. The adjustment control unit 151 stores, for example, the identification information of the battery cell 21 (or measurement circuit 11) and the current value of the internal current consumption in the current value storage unit 141 in association with each other.

[0044] Furthermore, the adjustment control unit 151 extracts the maximum current value from among the current values ​​of the internal consumption currents corresponding to each battery cell 21 stored in the current value storage unit 141. The adjustment control unit 151 determines the current setting value to flow to each current adjustment unit 13 based on the difference between the maximum current value and the current values ​​of the other internal consumption currents. The adjustment control unit 151 determines the current setting value using, for example, the following equation (1).

[0045] Current setting value = Maximum current value - Current value of internal consumption ... (1)

[0046] The adjustment control unit 151 stores each current setting value in the current setting storage unit 142. That is, the adjustment control unit 151 associates the identification information of the battery cell 21 (or measurement circuit 11) with the current setting value and stores it in the current setting storage unit 142.

[0047] Furthermore, the adjustment control unit 151 generates a pulse signal (PWM signal) with a duty cycle corresponding to the current setting value, as a control signal S, so that it matches the current setting value stored in the current setting memory unit 142, and outputs it to the gate terminal of the MOS transistor 133 of the current adjustment unit 13.

[0048] For example, if the maximum current value is "3mA (milliamperes)" and the internal current consumption value of the battery cell 21-1 is "2mA", the adjustment control unit 151 determines the current setting value of the battery cell 21-1 to be "1mA" according to equation (1). The adjustment control unit 151 also outputs a PWM signal corresponding to the current setting value as a control signal S to the gate terminal of the MOS transistor 133, and controls the current adjustment unit 13 to consume a current of "1mA". As a result, the adjustment control unit 151 adjusts the internal current consumption of the battery cell 21-1 to be "3mA" ("2mA" + "1mA").

[0049] Next, with reference to Figure 3, the battery unit 1 according to this embodiment will be described. Figure 3 is a flowchart showing an example of the operation of the battery unit 1 according to this embodiment. Here, the current adjustment process using the current adjustment unit 13 will be described.

[0050] As shown in Figure 3, the control device 10 of the battery unit 1 first acquires current values ​​from each current detection unit 12 (step S101). Each current detection unit 12 detects the internal current consumption of each battery cell 21 that is consumed by the measurement circuit 11 from each battery cell 21, and the adjustment control unit 151 of the control device 10 acquires the current value of the internal current consumption of each battery cell 21 from each current detection unit 12. The adjustment control unit 151 associates the identification information of the battery cell 21 (or measurement circuit 11) with the current value of the internal current consumption and stores it in the current value storage unit 141.

[0051] Next, the adjustment control unit 151 extracts the maximum value from among the acquired current values ​​(step S102). The adjustment control unit 151 extracts the maximum value of the internal consumption current from among the multiple internal consumption current values ​​stored in the current value storage unit 141. Here, the battery cell 21 associated with the maximum value of the current corresponds to the battery cell 21 with the highest internal consumption current.

[0052] Next, the adjustment control unit 151 determines the current setting value for each battery cell 21 based on the maximum value of each current (step S103). The adjustment control unit 151 determines the current setting value corresponding to each battery cell 21, for example, using equation (1) described above. The adjustment control unit 151 associates the identification information of the battery cell 21 (or measurement circuit 11) with the current setting value and stores it in the current setting storage unit 142.

[0053] Next, the adjustment control unit 151 controls each current adjustment unit 13 by PWM control so that each current value reaches its maximum value according to the current setting value (step S104). The adjustment control unit 151 acquires the current setting value stored in the current setting storage unit 142 and generates a PWM signal to supply the corresponding current adjustment unit 13 with the current setting value. The adjustment control unit 151 outputs the PWM signal as a control signal S to the current adjustment unit 13.

[0054] As a result, the MOS transistor 133 of the current adjustment unit 13 intermittently turns on at a predetermined rate based on the duty cycle of the PWM signal, causing the photodiode 132A of the photocoupler 132 to light up intermittently at a predetermined rate. In response, the phototransistor 132B of the photocoupler 132 intermittently turns on at a predetermined rate, and current flows intermittently at a predetermined rate through the adjustment resistor 131. On average, the adjustment resistor 131 becomes the current value of the current setting value. In this way, the adjustment control unit 151 adjusts the current consumed by each battery cell 21 by outputting the PWM signal as a control signal S to the current adjustment unit 13. The adjustment control unit 151 continues to execute PWM control.

[0055] After the processing in step S104, the adjustment control unit 151 terminates the current adjustment process. The current adjustment process shown in Figure 3 is performed at predetermined time intervals. Alternatively, the current adjustment process shown in Figure 3 may be performed, for example, when the battery module 20 is fully charged or fully discharged.

[0056] As described above, the battery unit 1 according to this embodiment comprises a plurality of battery cells 21, a measurement circuit 11 connected to each of the plurality of battery cells 21, a current adjustment unit 13, and an adjustment control unit 151. Each of the plurality of battery cells 21 is a battery cell containing a predetermined number (for example, one) of basic battery cells, and is rechargeable and dischargeable. The measurement circuit 11 measures the state of the battery cells 21 (for example, the voltage of the battery cells 21). The current detection unit 12 detects the internal consumption current of each battery cell 21, which includes the current flowing through each measurement circuit 11. The current adjustment unit 13 adjusts the internal consumption current of each of the plurality of battery cells 21, which includes the current flowing through each measurement circuit 11. The adjustment control unit 151 controls the current adjustment unit 13 so that the current values ​​of the internal consumption currents match among the respective battery cells 21, based on the current values ​​of the respective internal consumption currents.

[0057] As a result, the battery unit 1 according to this embodiment can reduce variations in the internal current consumption of the battery cells 21 by adjusting the current consumption of the measurement circuit 11 by the adjustment control unit 151. Therefore, the battery unit 1 according to this embodiment can reduce the occurrence of voltage variations in the battery cells 21.

[0058] For example, let's assume that the current value of the internal current consumption of each battery cell 21 is as follows: The internal current consumption of battery cell 21-1 is "2mA". The internal current consumption of battery cell 21-2 is "3mA". The internal current consumption of battery cell 21-3 is "3mA". The internal current consumption of battery cell 21-4 is "3mA".

[0059] In this case, battery cell 21-1 consumes a current of "2mAh" per hour, while battery cells 21-2 to 21-4 consume a current of "3mAh" per hour. In other words, there is a difference of "1mAh" in current consumption per hour between battery cell 21-1 and battery cells 21-2 to 21-4. For this reason, in conventional battery units, even if the charge levels of battery cells 21-2 to 21-4 reach "0" after prolonged use, the charge level of battery cell 21-1 does not reach "0". When charged, battery cell 21-1 reaches full charge first, causing the charge levels of battery cells 21-2 to 21-4 to decrease, resulting in voltage variations in battery cell 21.

[0060] In contrast, in the battery unit 1 according to this embodiment, by supplying an additional "1mA" via the adjustment control unit 151, the current value of the internal current consumption of battery cell 21-1 can be made to "3mA" ("2mA" + "1mA"), matching that of battery cells 21-2 to 21-4, as shown below.

[0061] The internal current consumption of battery cell 21-1 is "2mA" + "1mA". The internal current consumption of battery cell 21-2 is "3mA". The internal current consumption of battery cell 21-3 is "3mA". The internal current consumption of battery cell 21-4 is "3mA".

[0062] Therefore, in the battery unit 1 according to this embodiment, the internal current consumption of the battery cells 21 is adjusted to match, thereby reducing voltage variations in the battery cells 21. In this way, the battery unit 1 according to this embodiment can reduce variations in the internal current consumption of the battery cells 21, and thus can reduce the occurrence of voltage variations in the battery cells 21.

[0063] Furthermore, the battery unit 1 according to this embodiment includes a current detection unit 12 that detects the internal current consumption of each battery cell 21. The adjustment control unit 151 controls the current adjustment unit 13 based on the current value of the internal current consumption detected by the current detection unit 12, so that the current values ​​of the internal current consumption of each battery cell 21 match.

[0064] As a result, the battery unit 1 according to this embodiment can detect the current value of the internal current consumption of each battery cell 21 by itself using the current detection unit 12. Therefore, the battery unit 1 can adjust the current consumption to compensate for variations in the measurement circuit 11 by itself, thereby reducing variations in the internal current consumption of the battery cells 21.

[0065] Furthermore, in the battery unit 1 according to this embodiment, the internal current consumption of the battery cell 21 can be adjusted in response to changes in the characteristics of the measurement circuit 11 over time, for example, by periodically performing current adjustment processing by the adjustment control unit 151.

[0066] Furthermore, in this embodiment, the current adjustment unit 13 includes an adjustment resistor 131 that supplies a predetermined current from each of the multiple battery cells 21. The adjustment control unit 151 supplies the current from the battery cells 21 to the adjustment resistor 131 to adjust the current consumed by the battery cells 21.

[0067] As a result, the battery unit 1 according to this embodiment can easily reduce variations in the internal current consumption of the battery cells 21 with a simple configuration by using the adjustment resistor 131.

[0068] In this embodiment, the current adjustment unit 13 includes a switch unit (for example, a photocoupler 132) connected in series with the adjustment resistor 131. The adjustment control unit 151 adjusts the current consumed by the battery cell 21 by controlling the conduction of the switch unit (for example, the photocoupler 132) using pulse width modulation (PWM).

[0069] As a result, the battery unit 1 according to this embodiment can be controlled by pulse width modulation (PWM), allowing for more flexible adjustment of the internal current consumption without the need to change the resistance value of the adjustment resistor 131.

[0070] Furthermore, in this embodiment, the switch unit described above is a photocoupler 132. As a result, the battery unit 1 according to this embodiment can appropriately control the current adjustment unit 13 even when the power supply system of the control unit 15 and the power supply system of the battery cell 21 are different, by using the photocoupler 132.

[0071] Furthermore, in this embodiment, the adjustment control unit 151 controls the current adjustment unit 13 so that the current value of the other internal currents matches the maximum current value of the internal current. As a result, the battery unit 1 according to this embodiment can more easily match the current values ​​of the internal current consumption across multiple battery cells 21 by adjusting the current value of the internal current consumption to match the maximum current value.

[0072] Furthermore, the control device 10 according to this embodiment is a control device for a storage battery unit 1 comprising a plurality of chargeable and dischargeable battery cells 21, each containing a predetermined number (for example, one) of basic battery cells, and a measurement circuit 11 connected to each of the plurality of battery cells 21 for measuring the state of the battery cells 21, and comprises a current detection unit 12, a current adjustment unit 13, and an adjustment control unit 151. The current detection unit 12 detects the internal consumption current of each battery cell 21, which includes the current flowing through each measurement circuit 11. The current adjustment unit 13 adjusts the internal consumption current of each of the plurality of battery cells 21. The adjustment control unit 151 controls the current adjustment unit 13 so that the current values ​​of the internal consumption currents among the battery cells 21 match, based on the current values ​​of the internal consumption currents detected by the current detection unit 12. As a result, the control device 10 according to this embodiment has the same effect as the storage battery unit 1 described above, and can reduce the occurrence of voltage variations in the battery cells 21.

[0073] Furthermore, the control method according to this embodiment is a control method for a storage battery unit 1 comprising a plurality of chargeable and dischargeable battery cells 21, each containing a predetermined number (for example, one) of basic battery cells; a measurement circuit 11 connected to each of the plurality of battery cells 21 for measuring the state of the battery cells 21; a current detection unit 12 for detecting the internal consumption current of each battery cell 21, which includes the current flowing through each measurement circuit 11; and a current adjustment unit 13 for adjusting the internal consumption current of each of the plurality of battery cells 21, and includes an adjustment control step. In the adjustment control step, the adjustment control unit 151 controls the current adjustment unit 13 so that the current values ​​of the internal consumption currents among the respective battery cells 21 match, based on the current values ​​of the respective internal consumption currents detected by the current detection unit 12. As a result, the control method according to this embodiment has the same effect as the battery unit 1 described above, and can reduce the occurrence of voltage variations in the battery cells 21.

[0074] It should be noted that the present invention is not limited to the embodiments described above, and can be modified without departing from the spirit of the invention. For example, in the above embodiment, an example was described in which the adjustment control unit 151 generates the control signal S (PWM signal), but it is not limited to this, and for example, as shown in Figure 4, the control signal S (PWM signal) may be generated inside the current adjustment unit 13.

[0075] <First variation> Figure 4 is a block diagram showing an example of the configuration of the control device 10a according to the first modification of this embodiment. As shown in Figure 4, the battery unit 1a includes a control device 10a, which comprises a measurement circuit 11 and a current detection unit 12 connected to the battery cell 21, a current adjustment unit 13a, a storage unit 14, and a control unit 15a. The current adjustment unit 13a comprises an adjustment resistor 131, a photocoupler 132, a MOS transistor 133, a PWM setting unit 134, and a PWM signal generation circuit 135.

[0076] The PWM setting unit 134 is, for example, a register circuit that stores a PWM setting value corresponding to the current setting value, and stores the PWM setting value supplied from the control unit 15a. The PWM signal generation circuit 135 is a PWM signal generation circuit that includes, for example, a counter circuit, and generates a PWM signal based on the PWM setting value obtained from the PWM setting unit 134, and outputs the generated PWM signal as a control signal S to the gate terminal of the MOS transistor 133.

[0077] Furthermore, the control unit 15a is, for example, a processor including a CPU, and comprehensively controls the battery unit 1a (control device 10a and battery module 20). The control unit 15a includes an adjustment control unit 151a.

[0078] The basic function of the adjustment control unit 151a is the same as that of the adjustment control unit 151 described above. Instead of generating a PWM signal, the adjustment control unit 151a outputs a PWM setting value to the current adjustment unit 13a and stores the PWM setting value in the PWM setting unit 134.

[0079] Thus, in the modified battery unit 1a (control device 10a) of this embodiment, the current adjustment unit 13a generates a PWM signal, allowing for more flexible adjustment of internal current consumption with simpler control.

[0080] Furthermore, although the above embodiment describes an example in which the battery cell 21 comprises one basic battery cell, it is not limited to this, and the battery cell 21 may comprise multiple basic battery cells. Now, referring to Figure 5, a modified example will be described in which the battery cell 21 comprises multiple basic battery cells SCL in the example shown in Figure 4 described above.

[0081] <Second variation> Figure 5 is a block diagram showing an example of the configuration of the control device 10b according to a second modification of this embodiment. As shown in Figure 5, the battery unit 1b includes a control device 10b, which comprises a measurement circuit 11a and a current detection unit 12 connected to the battery cells 21a (21a-1, 21a-2, ...), a current adjustment unit 13a, a storage unit 14, and a control unit 15a.

[0082] In Figure 5, components identical to those in Figure 4 are given the same reference numerals, and their explanations are omitted. Battery cell 21a is an example of a case where multiple basic battery cells SCL are provided, and it comprises multiple (a predetermined number) basic battery cells SCL connected in series.

[0083] The measurement circuit 11a is connected to each of the multiple battery cells 21a and measures the state of the battery cells 21a. For example, the measurement circuit 11a is connected one-to-one with the battery cells 21a and measures the voltage (output voltage) of the battery cells 21a. Specifically, the measurement circuit 11a measures the voltage (output voltage) of each of a predetermined number of basic battery cells SCL that the battery cell 21a has.

[0084] The measurement circuit 11a receives power from the connected battery cell 21a and constantly consumes a predetermined current as the internal current of the battery cell 21a. Furthermore, there is variation in current consumption among the individual measurement circuits 11a, and the current consumption changes over time due to factors such as the deterioration of circuit elements.

[0085] In Figure 5, the measurement circuit 11a-1 is connected to the battery cell 21a-1. In the example shown in Figure 5, for the sake of explanation, only the connection between the measurement circuit 11a-1 and the battery cell 21a-1 is shown, and the other measurement circuits 11a are omitted from the description. However, each measurement circuit 11a and each current detection unit 12 are assumed to be connected to the corresponding battery cell 21a. Furthermore, the measurement circuit 11a includes a voltage detection unit 111a.

[0086] The voltage detection unit 111a is connected to the positive electrode (+ electrode) and negative electrode (- electrode) of a predetermined number of basic battery cells SCL provided in the battery cell 21a, and measures the voltage of each basic battery cell SCL. The voltage detection unit 111a is, for example, a voltmeter, a measurement IC such as an AFE, an ADC, etc.

[0087] In this modified example, the measurement circuit 11a operates using power supplied by the battery cell 21a. In this modified example, the current detection unit 12 detects the internal consumption current of each battery cell 21a, which includes the current flowing through each measurement circuit 11a. Furthermore, in this embodiment, the adjustment control unit 151a controls the current adjustment unit 13a based on the current value of each internal consumption current detected by the current detection unit 12, so that the current values ​​of the internal consumption currents among the battery cells 21a match.

[0088] As described above, the battery unit 1b (control device 10b) according to a modified version of this embodiment comprises a plurality of battery cells 21a, a measurement circuit 11a, a current detection unit 12, a current adjustment unit 13a, and a control unit 15a. The battery cells 21a include a predetermined number of basic battery cells SCL, where the predetermined number is, for example, a plurality.

[0089] As a result, the modified battery unit 1b (control device 10b) of this embodiment is equipped with a measurement circuit 11a, a current detection unit 12, and a current adjustment unit 13a for each of the multiple basic battery cells SCL. Therefore, the number of measurement circuits 11a, current detection units 12, and current adjustment units 13 can be reduced, and the occurrence of voltage variations in the battery cells 21a can be efficiently reduced for each of the multiple basic battery cells SCL.

[0090] Furthermore, in the above embodiment, a second modified example may be applied to the embodiment shown in Figure 1. That is, in the battery unit 1 (control device 10) shown in Figure 1, a battery cell 21a having a plurality of basic battery cells SCL and a measurement circuit 11a may be applied. Furthermore, the battery cell 21a may be connected in parallel, in addition to being connected in series, or in a combination of series and parallel.

[0091] Furthermore, although the above embodiment describes an example in which the current adjustment unit 13 (current adjustment unit 13a) is equipped with one adjustment resistor 131, it is not limited to this, and for example, multiple adjustment resistors 131 may be provided and used by switching between them or in combination. Also, the adjustment resistor 131 may be a variable resistor such as a volume resistor.

[0092] Furthermore, although the above embodiment describes an example in which the measurement circuit 11(11a) does not include the current detection unit 12 and the current adjustment unit 13(13a), the invention is not limited to this, and the measurement circuit 11(11a) may also include the current detection unit 12 or the current adjustment unit 13(13a).

[0093] Furthermore, in the above embodiment, an example was described in which the adjustment control unit 151 (151a) adjusts the current adjustment unit 13 (13a) to match the internal current consumption of the battery cell 21 (21a) to the maximum value of the current value. However, the invention is not limited to this, and other methods may be used to match the internal current consumption of the battery cell 21 (21a).

[0094] Furthermore, although the above embodiment describes an example in which the adjustment control unit 151 (151a) adjusts the current adjustment unit 13 (13a) using PWM control, the method is not limited to this, and the current adjustment unit 13 (13a) may be adjusted using other methods.

[0095] Furthermore, although the above embodiment describes an example in which a photocoupler 132 is used in the switch section, the invention is not limited to this, and other switches such as FETs (Field Effect Transistors) and relay switches may be used.

[0096] Furthermore, although the above embodiment describes an example in which the battery unit 1 (1a, 1b) is equipped with a current detection unit 12, it is not limited to this, and the current value detected by an external current detection unit may be stored in the current value storage unit 141 from the outside, without the current detection unit 12. In this case, for example, the variation in current values ​​may be detected at the factory at the time of shipment and stored in the current value storage unit 141 from the outside.

[0097] Furthermore, each component of the aforementioned battery unit 1 (1a, 1b) has a computer system inside. The processing in each component of the aforementioned battery unit 1 (1a, 1b) may be performed by recording a program for realizing the functions of each component on a computer-readable recording medium, loading the program recorded on this recording medium into the computer system, and executing it. Here, "loading the program recorded on the recording medium into the computer system and executing it" includes installing the program into the computer system. Here, "computer system" includes hardware such as the OS and peripheral devices.

[0098] Furthermore, "computer system" may include multiple computer devices connected via a network, including communication lines such as the Internet, WAN, LAN, and dedicated lines. "Computer-readable recording medium" refers to portable media such as flexible disks, magneto-optical disks, ROMs, and CD-ROMs, as well as storage devices such as hard disks built into computer systems. Thus, the recording medium storing the program may be a non-transient recording medium such as a CD-ROM.

[0099] Furthermore, the recording medium also includes internal or external recording media accessible from the distribution server for distributing the program. The program may be divided into multiple parts, downloaded at different times, and then combined in the respective configurations of the battery unit 1 (1a, 1b). The distribution servers for each of the divided programs may also be different. Moreover, "computer-readable recording media" includes volatile memory (RAM) within computer systems that act as servers or clients when a program is transmitted over a network, which retains the program for a certain period of time. The program itself may also be intended to implement some of the functions described above. Furthermore, the program may be a so-called differential file (differential program) that can implement the functions described above in combination with a program already recorded in the computer system.

[0100] Furthermore, some or all of the above-mentioned functions may be implemented as integrated circuits such as LSIs (Large Scale Integrations). Each of the above-mentioned functions may be implemented as an individual processor, or some or all of them may be integrated into a single processor. In addition, the method of implementing integrated circuits is not limited to LSIs; they may also be implemented using dedicated circuits or general-purpose processors. Furthermore, if advances in semiconductor technology lead to the emergence of integrated circuit technologies that can replace LSIs, integrated circuits using such technologies may be used. [Explanation of Symbols]

[0101] 1, 1a, 1b Battery Unit 10, 10a, 10b Control devices Measurement circuits for 11, 11a, 11-1, 11-2, 11-3, 11-4, and 11a-1. 12, 12-1, 12-2, 12-3, 12-4 Current detection unit 13, 13a, 13-1, 13-2, 13-3, 13-4 Current adjustment section 14 Storage section 15, 15a Control Unit 20 Battery Modules 21, 21a, 21-1, 21-2, 21-3, 21-4, 21a-1, 21a-2 battery cells 111, 111a Voltage detection unit 131 Adjustment resistance 132 Photocoupler 132A Photodiode 132B Phototransistor 133 MOS transistors 141 Current Value Storage Unit 142 Current setting memory unit 151, 151a Adjustment control unit SCL Basic Battery Cell

Claims

1. Each battery cell contains a predetermined number of basic battery cells, and comprises a plurality of rechargeable and dischargeable battery cells, A measurement circuit connected to each of the aforementioned plurality of battery cells for measuring the state of the battery cell, A current adjustment unit that adjusts the internal current consumption of each of the plurality of battery cells, which includes the current flowing through each of the measurement circuits, Based on the current value of each of the internal current consumptions, an adjustment control unit controls the current adjustment unit so that the current values ​​match among the respective battery cells. Equipped with, The current adjustment unit is, A control resistor that allows a predetermined current to flow from each of the aforementioned plurality of battery cells, The switch section, which is a photocoupler connected in series with the aforementioned adjustment resistor, Equipped with, The adjustment control unit adjusts the current consumed by the battery cell by controlling the conductivity of the switch unit by pulse width modulation. A battery storage unit characterized by the following features.

2. The predetermined number of basic battery cells is a single basic battery cell, The aforementioned battery cell is the single basic battery cell, The adjustment control unit controls the current adjustment unit so that the current values ​​match between each of the basic battery cells. The battery storage unit according to claim 1.

3. Each unit is equipped with a current detection unit that detects the internal current consumption of each of the above, The adjustment control unit, Based on the current value of each internal current consumption detected by the current detection unit, the current adjustment unit controls the current adjustment unit so that the current values ​​match between each of the battery cells. The battery storage unit according to feature 1.

4. The adjustment control unit controls the current adjustment unit so that the maximum value of the current value matches the other current values. A battery storage unit according to any one of claims 1 to 3, characterized by the features described herein.

5. Each of the battery cells is provided with a current setting storage unit that stores a current setting value obtained by subtracting the current value of the internal consumption current from the maximum value of the current value, The adjustment control unit, at least at predetermined time intervals, when the charging of the plurality of battery cells is complete, and when the discharging is complete, stores a current setting value for each battery cell in the current setting storage unit, and performs pulse width modulation control based on the current setting value for each battery cell stored in the current setting storage unit. The battery storage unit according to feature 4.

6. A control device for a battery storage unit comprising a plurality of battery cells, each containing a predetermined number of basic battery cells, which are chargeable and dischargeable, and a measurement circuit connected to each of the plurality of battery cells for measuring the state of the battery cells, A current adjustment unit that adjusts the internal current consumption of each of the plurality of battery cells, which includes the current flowing through each of the measurement circuits, Based on the current value of each of the internal current consumptions, an adjustment control unit controls the current adjustment unit so that the current values ​​match among the respective battery cells. Equipped with, The current adjustment unit is, A control resistor that allows a predetermined current to flow from each of the aforementioned plurality of battery cells, The switch section, which is a photocoupler connected in series with the aforementioned adjustment resistor, Equipped with, The adjustment control unit adjusts the current consumed by the battery cell by controlling the conductivity of the switch unit by pulse width modulation. A control device characterized by the following features.

7. A control method for a storage battery unit comprising: a plurality of battery cells, each containing a predetermined number of basic battery cells, which are chargeable and dischargeable; a measurement circuit connected to each of the plurality of battery cells for measuring the state of the battery cells; and a current adjustment unit for adjusting the internal consumption current of each of the plurality of battery cells, which includes the current flowing through each of the measurement circuits, wherein the control method for the storage battery unit comprises: The adjustment control unit includes an adjustment control step in which it controls the current adjustment unit so that the current values ​​match between the respective battery cells, based on the current values ​​of the internal current consumption of each of the battery cells. The current adjustment unit is, A control resistor that allows a predetermined current to flow from each of the aforementioned plurality of battery cells, The switch section, which is a photocoupler connected in series with the aforementioned adjustment resistor, Equipped with, In the adjustment control step, the adjustment control unit adjusts the current consumed by the battery cell by controlling the conduction of the switch unit by pulse width modulation. A control method characterized by the following:

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