JP2021157926A - Secondary battery device and secondary battery system - Google Patents

Abstract

To provide a secondary battery device and a secondary battery system that can more reliably control a secondary battery.SOLUTION: A secondary battery device includes a secondary battery, a detection unit for detecting the voltage, current, and temperature of the secondary battery, and a state calculation unit for calculating a battery state based on a detection result of the detection unit. The state calculation unit has a storage device and a processing device. The storage device has a first storage region for storing calculation information for calculating the battery state, and a second storage region for storing update information for updating the calculation information. The processing device executes processing P7 for calculating a current battery state by using the calculation information, processing P8 for calculating a new battery state by using the update information, and processing P11 for storing the update information in the first storage region and updating the calculation information when the amount of change between the current battery state and the new battery state is within a specified range.SELECTED DRAWING: Figure 13

Description

The present disclosure relates to a secondary battery device and a secondary battery system.

Conventionally, there have been known inventions relating to a battery deterioration calculation device that is small in scale, inexpensive, and capable of easily performing battery deterioration calculation even in a system operating state (see Patent Document 1 below). The battery deterioration calculation device described in Patent Document 1 is communicably connected to the secondary battery device (see the same document, abstract, claim 1, paragraph 0007, etc.).

The secondary battery device includes a control unit having a non-volatile memory. The non-volatile memory has average battery capacity data indicating the average battery capacity of the secondary battery, average temperature data indicating the average battery temperature of the secondary battery, and the number of cycles of charging or discharging the secondary battery in a predetermined time unit. Data is stored as battery usage history data.

The battery deterioration calculation device includes a memory, a receiving unit, and a battery deterioration calculation unit. The memory stores battery deterioration tendency data calculated in advance with the battery capacity and temperature as parameters. The receiving unit receives the battery usage history data from the control unit. The battery deterioration calculation unit combines the battery deterioration tendency data and the battery usage history data to calculate the battery capacity according to the battery deterioration.

JP-A-2015-007616

In the conventional battery deterioration calculation device, the battery usage history data stored in the non-volatile memory of the control unit of the secondary battery device is received by the receiving unit, and the battery deterioration calculation unit calculates in advance the battery capacity and temperature as parameters. By combining with the battery deterioration tendency data, the battery capacity according to the battery deterioration is calculated. Here, this conventional battery deterioration calculation device is characterized in that the battery capacity calculation algorithm and the like can be freely updated without time constraints. In updating such an algorithm, if there is a function to determine whether the updated information is appropriate information, it is considered that a secondary battery device capable of more reliable control can be realized.

The present disclosure provides a secondary battery device and a secondary battery system capable of more reliably controlling a secondary battery.

One aspect of the present disclosure includes a secondary battery, a detection unit that detects the voltage, current, and temperature of the secondary battery, and a state calculation unit that calculates the battery state based on the detection result of the detection unit. A secondary battery device including a state calculation unit having a storage device and a processing device, and the storage device includes a first storage area for storing calculation information for calculating the battery state. The processing device has a second storage area for storing update information for updating the calculation information, and the processing device includes a state detection process for calculating the current battery state using the calculation information and the update information. The update verification process for calculating the new battery state using the above, and the update information when the amount of state change between the current battery state and the new battery state is within a specified range. It is a secondary battery device characterized by executing an update process of storing in the first storage area and updating the calculation information.

According to the present disclosure, it is possible to provide a secondary battery device and a secondary battery system capable of more reliably controlling a secondary battery.

The block diagram which shows one Embodiment of the secondary battery system of this disclosure. FIG. 6 is a schematic configuration diagram of a secondary battery device constituting the secondary battery system of FIG. FIG. 2 is a functional block diagram of a state calculation unit of the secondary battery device of FIG. The graph which shows the relationship between the open circuit voltage of the cell of the secondary battery apparatus of FIG. 2 and SOC. FIG. 2 is an equivalent circuit diagram of a cell cell constituting the cell cell group of the secondary battery device of FIG. The graph which shows an example of the time change of the current flowing through a battery and the voltage of a battery. A graph showing the time change of battery voltage. The graph which shows an example of the relationship between the resistance increase rate of a battery and the capacity maintenance rate. The histogram which shows an example of the history information of the cell group of the secondary battery apparatus of FIG. The functional block diagram of the management apparatus constituting the secondary battery system of FIG. The flow chart which shows an example of the processing flow of the management apparatus of FIG. FIG. 9 is a functional block diagram of a calculation function of the management device of FIG. The graph which shows an example of the state change amount calculated by the calculation function of FIG. The flow chart which shows an example of the processing flow of the state calculation part of FIG. The flow chart which shows the modification of the processing flow of the state calculation part of FIG. The functional block diagram which shows the modification of the management apparatus of FIG.

Hereinafter, an embodiment of the secondary battery device and the secondary battery system of the present disclosure will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the secondary battery system of the present disclosure. In the example shown in FIG. 1, the secondary battery system 1 of the present embodiment constitutes, for example, a part of the photovoltaic power generation system PGS. The photovoltaic power generation system PGS includes, for example, a photovoltaic power generation panel 2, a power system 3, power conditioners (PCS) 4 and 5, and a control device 6 in addition to the secondary battery system 1.

The secondary battery system 1 is connected to the PCS 5 via, for example, power wiring. The photovoltaic power generation panel 2 is connected to the PCS 4 via, for example, power wiring. The power system 3 is connected to the PCS 4 and PCS 5 via, for example, power wiring. The control device 6 is connected to the secondary battery system 1, PCS4, and PCS5 via, for example, an information communication line. The control device 6 is a computer system that controls the secondary battery systems 1, PCS4, and PCS5 by performing information communication with them via an information communication line.

The photovoltaic power generation system PGS operates under the control of the control device 6, for example, as follows. The photovoltaic power generation panel 2 receives sunlight to generate DC power. The PCS 4 converts the DC power output from the photovoltaic power generation panel 2 into AC power and supplies it to the power system 3. The PCS 5 converts a part or all of the AC power output from the PCS 4 and supplied to the power system 3 into DC power according to the situation, and supplies the AC power to the secondary battery system 1.

The secondary battery system 1 is charged by the DC power supplied from the PCS 5 and stores electrical energy. The secondary battery system 1 outputs the stored electric energy as DC power depending on the situation. The PCS 5 converts the DC power output from the secondary battery system 1 into AC power and supplies it to the power system 3. In this way, the photovoltaic power generation system PGS can compensate the generated power of the photovoltaic power generation panel 2 that fluctuates depending on the weather by the output of the secondary battery system 1, and can smooth the output to the power system 3. can. The secondary battery system 1 includes, for example, a secondary battery device 11 and a management device 12.

FIG. 2 is a schematic configuration diagram of a secondary battery device 11 constituting the secondary battery system 1 of FIG. The secondary battery device 11 includes, for example, a cell group 111, a pair of external terminals 112, a current sensor 113, a temperature sensor 114, a battery management unit 115, a state calculation unit 116, an information input terminal 117, and the like. It is equipped with an information output terminal 118.

The cell group 111 is composed of, for example, a plurality of cell cells connected in series. The cell is not particularly limited, but is, for example, a square lithium ion secondary battery. Although not shown, the secondary battery device 11 may include, for example, a plurality of cell groups 111. The plurality of cell groups 111 are connected in series or in parallel, for example. Further, a plurality of cell groups 111 connected in series may be connected in parallel.

In the pair of external terminals 112, one external terminal 112 is connected to the negative electrode terminal of the cell group 111 via the power wiring, and the other external terminal 112 is connected to the positive electrode terminal of the cell group 111 via the power wiring. ing. Further, the pair of external terminals 112 are connected to the PCS 5 shown in FIG. 1 via, for example, power wiring.

The current sensor 113 is connected to, for example, the power wiring between the cell group 111 and the external terminal 112, and measures the current flowing through the cell group 111. The temperature sensor 114 is attached to at least one of a plurality of cells constituting the cell group 111, and measures the temperature of the cell group 111, for example.

The battery management unit 115 and the state calculation unit 116 are, for example, a microcontroller or firmware including a processing device such as a CPU, a storage device such as a RAM or ROM, a timer, and a signal input / output unit. The battery management unit 115 and the state calculation unit 116, for example, realize various functions described below by executing a program stored in the storage device by the processing device.

The battery management unit 115 has, for example, a function as a voltage sensor for measuring the voltage of each cell constituting the cell group 111 and a function of equalizing the voltage between the individual cells. There is. The state calculation unit 116 is connected to the current sensor 113, the temperature sensor 114, and the battery management unit 115 via, for example, a signal input / output unit. The state calculation unit 116 has, for example, a function of calculating the battery state, which is the state of the cell group 111.

The battery state of the cell group 111 calculated by the state calculation unit 116 is, for example, the charge state (SOC), the deterioration state (SOH), the maximum power or current that can be input / output, the presence / absence of abnormality, and the characteristics of the cell group 111. Includes parameters, history information, etc. Further, the state calculation unit 116 multiplies, for example, the current value acquired from the current sensor 113 and the voltage of each cell acquired from the battery management unit 115 to obtain the output power and the input power of the cell group 111. It has a function to calculate.

The state calculation unit 116, for example, transmits the calculated information including the battery state of the cell group 111 via the information output terminal 118 to the management device 12 of the secondary battery system 1 shown in FIG. 1 or the photovoltaic power generation system PGS. Is output to the control device 6. Further, the state calculation unit 116 acquires, for example, information used for various calculations from the management device 12 via the information input terminal 117.

FIG. 3 is a functional block diagram of the state calculation unit 116 shown in FIG. The state calculation unit 116 includes, for example, a data reception function F1, a characteristic parameter storage function F2, an update parameter storage function F3, a calculation algorithm storage function F4, an update algorithm storage function F5, and a battery state. It has a calculation function F6. Further, the state calculation unit 116 has, for example, a history management function F7, a battery state determination function F8, and a data transmission function F9.

The reception function F1 receives, for example, the information input from the management device 12 of the secondary battery system 1 shown in FIG. 1 to the information input terminal 117 of the secondary battery device 11. Further, the receiving function F1 outputs the received information to, for example, each function such as the storage function F2, the storage function F3, the storage function F4, the storage function F5, and the determination function F8. Further, the reception function F1 receives the determination result from the determination function F8.

The storage function F2 is, for example, a function of storing characteristic parameters included in the calculation information for calculating the battery state of the cell group 111 in the first storage area of the storage device of the state calculation unit 116. The storage function F3 is, for example, a function of storing update parameters included in the update information for updating the calculation information in the second storage area of the storage device of the state calculation unit 116.

The storage function F4 is, for example, a function of storing the calculation algorithm included in the calculation information for calculating the battery state of the cell group 111 in the first storage area of the storage device of the state calculation unit 116. The storage function F5 is, for example, a function of storing the update algorithm included in the update information for updating the calculation information in the second storage area of the storage device of the state calculation unit 116.

The calculation function F6 uses, for example, the calculation information stored in the first storage area storage of the storage device of the state calculation unit 116 to calculate the current battery state of the unit cell group 111 before the calculation information is updated by the update information. It is a function to do. Further, the calculation function F6 uses, for example, the update information stored in the second storage area storage of the storage device of the state calculation unit 116, and the calculation function F6 of the new cell group 111 when the calculation information is updated by the update information. It is a function to calculate the battery status.

As described above, the calculation information for calculating the battery state of the cell group 111 includes, for example, a characteristic parameter and a calculation algorithm. Further, the update information for updating the calculation information includes, for example, an update parameter and an update algorithm.

In the management function F7, for example, information of the cell group 111 including the current value I, the temperature T, and the voltage value V is input from the current sensor 113, the temperature sensor 114, and the battery management unit 115, and the current state from the calculation function F6. The battery status of the cell group 111 of is input. The management function F7 is a function of managing the history information, for example, calculating the history information of the cell group 111, which will be described later, storing it in the storage device of the state calculation unit 116, and outputting it to the transmission function F9 as needed. Is.

The determination function F8 determines, for example, whether or not the amount of state change between the current battery state and the new battery state of the cell group 111 input from the calculation function F6 is within the specified range. It is a function. The determination function F8 outputs the determination result to the reception function F1, for example. For example, the transmission function F9 transmits the information input from the calculation function F6 and the management function F7 to the management device 12 of the secondary battery system 1 shown in FIG. 1 via the information output terminal 118 of the secondary battery device 11. It is output to the control device 6 of the solar power generation system PGS.

Hereinafter, the battery state of the cell group 111 calculated by the calculation function F6 will be described. As described above, the battery state of the cell group 111 includes, for example, the SOC and SOH of the cell group 111, the maximum power or current that can be input / output, the presence / absence of abnormality, and history information.

FIG. 4 is a graph showing an example of the relationship between the open circuit voltage OCV and SOC of the cells constituting the cell group 111. The SOC of the cell group 111 can be calculated, for example, by a voltage reference. In this case, as shown in FIG. 4, the relationship between the open circuit voltage OCV and the SOC of the individual cells constituting the cell group 111 is specified in advance and stored in the storage device of the state calculation unit 116. Thereby, by calculating the open circuit voltage OCV of the cell, the SOC of the cell can be estimated from the relationship between the open circuit voltage OCV of the cell and the SOC shown in FIG. The open circuit voltage OCV of the cell can be calculated as follows, for example.

FIG. 5 is an example of an equivalent circuit diagram of the cells constituting the cell group 111. In FIG. 5, the open circuit voltage OCV and the internal resistance R of the cell are connected in series, and the polarization resistance component Rp and the capacitance component C connected in parallel are combined with the open circuit voltage OCV and the internal resistance R. It represents the state of being connected in series. When the current I flows through the cell, the voltage CCV between the terminals of the cell is expressed by the following equation (1) using the open circuit voltage OCV, the internal resistance R, and the polarization voltage Vp. The polarization voltage Vp is the voltage across the polarization resistance component and the capacitance component connected in parallel.

CCV = OCV + IR + Vp ・ ・ ・ (1)

When the cell is charged or discharged, the open circuit voltage OCV of the cell cannot be measured directly. However, in this case, as shown in the following equation (2), the open circuit voltage of the cell is obtained by subtracting the voltage drop I / R due to the internal resistance and the polarization voltage Vp from the voltage CCV between the terminals of the cell. OCV can be calculated.

OCV = CCV-I ・ R-Vp ・ ・ ・ (2)

Although details will be described later, the management device 12 shown in FIG. 1 includes a processing device such as a CPU (not shown) and a storage device such as a ROM or RAM. The relationship between the open circuit voltage OCV and SOC of the cell, the internal resistance R, the polarization resistance component Rp and the capacitance component C are calculated by, for example, the processing device of the management device 12, and are arithmetic information in the storage device of the management device 12. Accumulated as a characteristic parameter. The characteristic parameters of the cell cells stored as calculation information in the storage device of the management device 12 are distributed to the secondary battery device 11, and when the voltage CCV and the current I between the terminals of the cell cells acquired by the secondary battery device 11 are obtained. The above-mentioned arithmetic processing is realized by using the series information.

It is preferable that the characteristic parameters of the cell are specified in advance for each SOC and temperature of the cell and stored in the storage device of the state calculation unit 116 in order to improve the estimation accuracy of the SOC. However, if the materials constituting the cell are different, the relationship between the open circuit voltage OCV and the SOC will be different. Therefore, in this voltage-based SOC estimation method, the SOC estimation accuracy may differ depending on the characteristics of the cell.

Further, the SOC of the battery can be calculated, for example, by integrating the current values. In this case, the current value input to the battery and the current value output from the battery are measured, and the current values are integrated to calculate the SOC. Specifically, the SOC is first estimated based on the voltage reference described above. Then, the SOC of the voltage reference is used as the initial value SOCv, and further, the current I measured by the current sensor 113 and the full charge capacity Qmax of the battery are used, and the SOC by integrating the current values by the following equation (3). SOCi is calculated.

SOCi = SOCv + 100 × ∫Idt / Qmax ・ ・ ・ (3)

In the method of estimating SOC by integrating the current values, the measurement error included in the measured value of the current I is also integrated, so that the SOC error may increase with the passage of time. Therefore, after integrating the current values over a predetermined time, measures such as correcting the SOC error are required. As described above, each method of estimating SOC by voltage reference or integration of current value has advantages and disadvantages. Therefore, the SOC estimation method is appropriately selected according to the conditions such as the characteristics of the cell cell, the sensor performance, and the surrounding environment, and the SOC estimation accuracy is ensured.

Further, the SOC may be estimated with higher accuracy by combining the estimation of the SOC based on the voltage reference and the estimation of the SOC by integrating the current value. In this case, the coefficient W for combining the SOCv, which is the SOC estimated by the voltage reference, and the SOCi, which is the SOC estimated by integrating the current values, is appropriately set. As a result, the SOCc, which is the SOC based on the combination of the voltage reference and the integration of the current value, can be calculated by the following equation (4).

SOCc = W x SOCv + (1-W) x SOCi ... (4)

As described above, the characteristic parameters of the cell cell required for the calculation of SOC differ depending on the estimation method. The characteristic parameters of the battery include, for example, the relationship between the open circuit voltage OCV and SOC of the battery as shown in FIG. 4, the internal resistance R of the battery, the polarization resistance component Rp and the capacitance C as shown in FIG. Further, the characteristic parameter includes, for example, the full charge capacity Qmax of the battery. These characteristic parameters change as the battery deteriorates. Therefore, in order to improve the SOC estimation accuracy, it is necessary to grasp the changes in the characteristic parameters due to the deterioration of the battery. Furthermore, it is necessary to appropriately select the SOC calculation method.

In addition to the SOC, other information contained in the battery state, such as the maximum current and maximum power that can be charged and discharged, and the amount of power that can be supplied, is also used to calculate the various characteristic parameters described above. You need to figure it out. Specifically, the maximum current Ic_max at which the battery can be charged and the maximum current Id_max at which the battery can be discharged are represented by, for example, the following equations (5) and (6).

Ic_max = (Battery upper limit voltage-OCV) / Rt ... (5)
Id_max = (OCV-lower limit voltage of battery) / Rt ... (6)

In the above equations (5) and (6), the internal resistance Rt is determined based on the charge duration in consideration of all of the internal resistance R, the polarization resistance component Rp, and the capacitance component C of the battery. Therefore, the maximum currents Ic_max and Id_max can be estimated with high accuracy by grasping the effects of the deterioration of the internal resistance R, the polarization resistance component Rp, and the capacitance component C of the battery. Further, by multiplying the estimated maximum currents Ic_max and Id_max by a voltage, the maximum power that can be charged and discharged can be estimated with high accuracy.

As described above, by accurately grasping the characteristic parameters of the battery, which is the calculation information, and appropriately selecting the calculation method, the calculation function F6 of the state calculation unit 116 constituting the secondary battery device 11 enables the battery. The state can be calculated accurately. In the following, as an example of the calculation information for calculating the battery state, a method of calculating the internal resistance and SOH, which are indicators of deterioration, will be described.

When the battery deteriorates, the parameters of the components of the equivalent circuit shown in FIG. 5 change. Specifically, for example, the internal resistance of the battery increases, and the full charge capacity Qmax of the battery in the above formula (3) also decreases. The SOH of the battery includes, for example, a resistance increase rate SOHR as an increase rate of the internal resistance of the battery and a capacity retention rate SOHQ as a maintenance rate of the fully charged capacity of the battery. In the following, first, a method of calculating the resistance increase rate SOHR will be described with reference to FIG. This resistance increase rate SOHR is calculated, for example, by the calculation function F6 of the state calculation unit 116 constituting the secondary battery device 11.

FIG. 6 is a graph showing an example of the time change of the current flowing through the battery and the voltage of the battery. From time t0 to time t1, the current flowing through the battery is in a dormant state of zero. At time t1, the battery starts to be discharged and continues to be discharged until time t2. At this time, the current I flows through the battery, and the voltage of the battery drops by the product of the current I and the internal resistance R. Assuming that the voltage at each time is CCV (t), the current at each time is I (t), and the voltage and current measurement intervals are Δt, the internal resistance R is expressed by the following equation (7). In the example of FIG. 6, by using the following equation, R can be obtained at two points, time t1 and time t2, where the change in current occurs.

R = {CCV (t) -CCV (t-Δt)} / {I (t) -I (t-Δt)}
... (7)

The method for calculating the internal resistance R is not limited to the above method. Next, as shown in the following formula (8), the 100% ratio of the current internal resistance R of the battery obtained by the above formula (7) to the internal resistance Ro at the start of use or the initial use of the battery is calculated. , Battery resistance increase rate SOHR can be estimated.

SOHR = 100 × (R / Ro) ・ ・ ・ (8)

For the internal resistance R, for example, the above equations (7) and (8) are stored in the storage device of the state calculation unit 116 by the storage function F4 of the state calculation unit 116 constituting the secondary battery device 11, and the state calculation is performed. It can be calculated using the equations (7) and (8) by the calculation function F6 of the unit 116. Next, a method of calculating the capacity retention rate SOHQ of the battery will be described with reference to FIGS. 7A and 7B.

FIG. 7A is a graph showing the time change of the battery voltage. The full charge capacity Qmax of the battery can be calculated, for example, as follows. In the example shown in FIG. 7A, the battery is in a dormant state from the time t0 to the time t1 as in the example shown in FIG. After that, the battery discharge is started at time t1, the discharge is continued from time t1 to time t2, and the discharge is stopped after time t2.

In this case, the SOC (SOC1) of the battery before the start of discharge before the time t1 is estimated based on the relationship between the open circuit voltage OCV of the battery and the SOC as shown in FIG. Similarly, the SOC (SOC2) of the battery at the time t3 when the voltage becomes stable after a sufficient time has passed after the discharge is stopped after the time t2 is estimated. Using SOC1 and SOC2, which are SOCs in the hibernation state before and after discharging these batteries, the full charge capacity Qmax of the batteries can be calculated by the following equation (9).

Qmax = 100 × ∫Idt / (SOC2-SOC1) ・ ・ ・ (9)

Further, the full charge capacity Qmax_o at the start or initial use of the battery and the current full charge capacity Qmax of the battery are obtained by the equation (9). Then, the capacity retention rate SOHQ of the battery can be estimated by calculating the percentage of the current full charge capacity Qmax with respect to the initial full charge capacity Qmax_o of the battery as in the following equation (10).

SOHQ = 100 × (Qmax / Qmax_o) ・ ・ ・ (10)

In this method of estimating the capacity retention rate SOHQ of the battery, the measurement error included in the measured value of the current I is also integrated as in the above equation (9), so that the error of the full charge capacity Qmax of the battery increases with the passage of time. May expand. Therefore, for example, a charge / discharge pattern is selected so that the difference between the SOC (SOC1) of the battery before charging / discharging and the SOC (SOC2) of the battery after charging / discharging becomes large in a short time, and the calculation of the above equation (9) is performed. By performing the above, it becomes possible to suppress the error.

FIG. 7B is a graph showing an example of the relationship between the resistance increase rate SOHR of the battery and the capacity retention rate SOHQ. Hereinafter, a method for estimating the capacity retention rate SOHQ, which is different from the above-mentioned estimation method, will be described. In this estimation method, as shown in FIG. 7B, the relationship between the resistance increase rate SOHR and the capacitance maintenance rate SOHRQ is specified in advance and stored in the storage device of the state calculation unit 116.

Thereby, by calculating the resistance increase rate SOHR by the above formula (8), as shown in FIG. 7B, the capacity retention rate SOHR can be estimated based on the resistance increase rate SOHR. Further, using the capacity retention rate SOHQ estimated by this method and the initial full charge capacity Qmax_o of the battery, the current full charge capacity Qmax of the battery can be estimated based on the equation (10).

In this method, since the current I is not integrated as in the above equation (9), the measurement error included in the measured value does not accumulate. However, the relationship between the resistance increase rate SOHR and the capacity retention rate SOHQ as shown in FIG. 7B may change depending on the historical information including the battery usage conditions. Therefore, in order to estimate the capacity retention rate SOHRQ of the battery with high accuracy, a test for deteriorating the battery with various historical information is performed, and the resistance increase rate SOHR and the capacity retention rate as shown in FIG. 7B are performed for each history information. Identify the relationship with SOHQ.

The relationship between the battery resistance increase rate SOHR and the capacity maintenance rate SOHQ for each of the various historical information obtained by such a test is, for example, as a characteristic parameter which is the calculation information of the battery in the storage device of the management device 12. Be remembered. The processing device of the management device 12 has characteristic parameters stored in the storage device of the management device 12, for example, according to the history information including the usage history of the cell group 111 acquired from the secondary battery device 11, for example, the battery. Select the relationship between the resistance increase rate SOHR and the capacity retention rate SOHQ.

FIG. 8 is a histogram showing an example of the history information of the cell group 111 of the secondary battery device 11. FIG. 8 shows the frequency of occurrence of the battery stay SOC, the battery stay temperature, and the battery charge / discharge current. In the state calculation unit 116 of the secondary battery device 11, the history management function F7 shown in FIG. 3 is, for example, based on the time series data of the SOC, temperature, and charge / discharge current stored in the storage device, of the unit battery group 111. It has a function of extracting history information in a histogram format as shown in FIG. Further, the transmission function F9 of the state calculation unit 116 has a function of outputting the history information of the cell group 111 extracted by the management function F7 to the management device 12 via the information output terminal 118.

FIG. 9 is a functional block diagram of the management device 12 shown in FIG. The management device 12 is, for example, a microcontroller or firmware including a processing device such as a CPU, a storage device such as a RAM or ROM, a timer, and a signal input / output unit 121. The management device 12 is communicably connected to, for example, the information input terminal 117 and the information output terminal 118 of the secondary battery device 11 shown in FIG. 2 via the input / output unit 121.

The management device 12 realizes various functions described below by, for example, executing a program stored in the storage device by the processing device. The management device 12 has, for example, a calculation information search function F10 for calculating the battery state, a calculation information storage function F11, and a calculation function F12 in a specified range.

The search function F10 has a function of acquiring the history information and the battery status of the cell group 111 output from the secondary battery device 11 via the input / output unit 121. As described above, the battery status includes, for example, the SOC and SOH of the battery, the maximum current or the maximum power that the battery can be charged, the maximum current and the maximum power that the battery can be discharged, the presence / absence of an abnormality in the battery, and the characteristic information of the battery. Includes battery history information and more.

Further, the search function F10 has a function of searching and selecting the calculation information stored in the storage device of the management device 12 by the storage function F11 based on the battery information including the history information and the type of the battery. Further, the search function F10 has a function of outputting the selected calculation information to the calculation function F12 and outputting the selected calculation information to the secondary battery device 11 via the input / output unit 121. The calculation information output from the search function F10 to the secondary battery device 11 includes, for example, at least one of a battery characteristic parameter and a calculation algorithm for calculating the battery state by the state calculation unit 116 of the secondary battery device 11.

The storage function F11 stores, for example, arithmetic information including characteristic parameters for each battery history information obtained by a battery test including a charge / discharge test in which the battery is deteriorated by various history information as a database in the storage device of the management device 12. It has a function to memorize. For the battery test, for example, a discharge pattern as shown in FIG. 6 can be used.

More specifically, in the battery test, for example, a battery having the same configuration as the cell group 111 of the secondary battery device 11 is charged to a fully charged state, and the voltage of the battery is the lower limit in the discharge pattern as shown in FIG. Discharge until the voltage is reached. The current value at the time of discharging the battery should be small. In this battery test, the full charge capacity Qmax of the battery can be calculated by measuring the current value at the time of discharging the battery and integrating the measured current value over time.

Further, in the battery test, for example, a battery having the same configuration as the cell group 111 of the secondary battery device 11 is charged to a fully charged state, and the discharge pattern as shown in FIG. 6 is used until the battery reaches a predetermined SOC. Discharge. The relationship between this predetermined SOC and the open circuit voltage OCV of the battery after a sufficient time has elapsed after the discharge test is recorded by repeatedly performing the discharge test. As a result, the relationship between the open circuit voltage OCV of the battery and the SOC as shown in FIG. 4 can be obtained.

Further, the battery test is performed in the discharge pattern as shown in FIG. 6, and the internal resistance R of the battery is extracted from the fluctuation of the battery voltage immediately before the start of discharge, immediately after the start of discharge, or immediately before the end of discharge or immediately after the end of discharge, and the battery is discharged. Measure and analyze the voltage change during hibernation after the end. Thereby, it is possible to specify the polarization resistance Rp and the capacitance C.

The characteristic parameters for each battery history information obtained by the charge / discharge test are real-time during use of the secondary battery device 11, such as the above-mentioned full charge capacity Qmax, open circuit voltage OCV, polarization resistance Rp and capacitance C. Includes characteristic parameters for which it is difficult to determine the current value.

The characteristic parameters for which it is difficult to obtain the current value in real time while using the secondary battery device 11 are, for example, the relationship between the open circuit voltage OCV and SOC of the battery shown in FIG. 4, and the polarization resistance Rp of the battery shown in FIG. , And the capacitance C, the relationship between the battery resistance increase rate SOHR and the capacity retention rate SOHQ shown in FIG. 7B, and the full charge capacity Qmax and the capacity retention rate SOHQ. Further, the storage function F11 stores, for example, a characteristic parameter in the storage device of the management device 12 for each of various historical information of the battery. Further, the storage function F11 may store the internal resistance R of the battery as a characteristic parameter.

The calculation function F12 has a function of acquiring calculation information for calculating the battery state of the secondary battery device 11 from the secondary battery device 11 via the input / output unit 121. Further, the calculation function F12 calculates the current battery state and the new battery state by using the current calculation information acquired from the secondary battery device 11 and the new calculation information selected by the search function F10. Has the function of Further, the calculation function F12 has a function of calculating the amount of state change between the current battery state and the new battery state. Further, the calculation function F12 has a function of defining a range of the state change amount based on the calculated state change amount.

Hereinafter, the operation of the secondary battery device 11 and the secondary battery system 1 of the present embodiment will be described with reference to FIGS. 10 to 14.

FIG. 10 is a flow chart showing an example of the processing flow of the secondary battery system 1. When the secondary battery system 1 shown in FIG. 1 starts the process, the management device 12 of the secondary battery system 1 executes the process P1 for receiving the battery status and the calculation information from the secondary battery device 11.

Specifically, in the process P1, as shown in FIG. 2, the state calculation unit 116 of the secondary battery device 11 uses the calculation information stored in the storage device by the processing device to use the battery state of the cell group 111. Is calculated, and the calculated battery state is output to the management device 12 via the information output terminal 118. The management device 12 receives the battery status and battery history information output from the secondary battery device 11 by the processing device via the input / output unit 121 shown in FIG.

More specifically, the state calculation unit 116 of the secondary battery device 11 calculates the battery state using the calculation information by the calculation function F6 shown in FIG. The calculation function F6 calculates the battery state as calculation information using, for example, the characteristic parameters of the battery and the calculation algorithm stored in the first storage area of the storage device of the state calculation unit 116 by the storage function F2 and the storage function F4. do. The battery state calculated by the calculation function F6 includes the SOC of the battery, the internal resistance R, and the resistance increase rate SOHR. This battery state is output to the management device 12 via the information output terminal 118 by the transmission function F9 shown in FIG. 3 together with the calculation information used for the calculation, and is output to the management device 12 via the input / output unit 121 shown in FIG. Received by the search function F10.

Further, the state calculation unit 116 of the secondary battery device 11 calculates the battery history information as the battery state, for example, as shown in FIG. 8, by the management function F7 shown in FIG. 3, and stores the state calculation unit 116. To memorize. The battery history information stored in the storage device of the state calculation unit 116 is output to the management device 12 via the information output terminal 118 by the transmission function F9 shown in FIG. 3, and is output to the management device 12 via the input / output unit 121 shown in FIG. It is received by the search function F10 of the management device 12. As a result, the process P1 shown in FIG. 10 is completed.

Next, the search function F10 of the management device 12 stores the calculation information corresponding to the battery state received from the secondary battery device 11 in the database stored in the storage device of the management device 12 by the storage function F11. Select from the information and get it. The database stored in the storage device of the management device 12 includes, for example, a plurality of arithmetic information corresponding to various historical information of the battery obtained by the battery test described above. This calculation information includes characteristic parameters for which it is difficult to obtain the current value in real time while the secondary battery device 11 is in use.

The search function F10 uses the history information received from the secondary battery device 11 as a reference to obtain new calculation information corresponding to similar history information from a plurality of calculation information corresponding to various history information as described above. Select and get. As a result, the process P2 shown in FIG. 10 is completed. In the following, the calculation information received by the search function F10 from the secondary battery device 11 is referred to as "current calculation information", and the new calculation information acquired by the search function F10 from the database stored in the storage device of the management device 12 is referred to as "current calculation information". It is called "update information". After the end of the process P2, the arithmetic function F12 of the management device 12 executes, for example, a process P3 for setting a virtual charge / discharge pattern of the battery, which is used in the process P4 for defining the range of the state change amount.

FIG. 11 is a functional block diagram of the calculation function F12 shown in FIG. The calculation function F12 has, for example, a charge / discharge pattern setting function F121, a current battery state calculation function F122, a new battery state calculation function F123, and a state change amount calculation function F124.

In the process P3, the setting function F121 extracts, for example, the frequency of occurrence of the charge / discharge current included in the battery history information D1 acquired from the secondary battery device 11 by the search function F10. Further, the setting function F121 selects and sets a charge / discharge pattern similar to the generated frequency of the extracted charge / discharge current from the plurality of charge / discharge patterns stored in the storage device of the management device 12. As an example, the above-mentioned charging / discharging pattern selection method has been described, but information that can identify the application (UPS, automobile, etc.) in which the secondary battery device 11 is used is recorded in the history information. With reference to this, the setting function F121 may select and set a charge / discharge pattern for the same purpose from the charge / discharge patterns stored in the storage device of the management device 12 according to the use. As a result, the process P3 shown in FIG. 10 is completed.

Next, the calculation function F12 of the management device 12 executes, for example, the process P4 for setting the range of the state change amount. Specifically, as shown in FIG. 11, the calculation function F122 and the calculation function F123 each acquire the charge / discharge pattern D2 set in the setting function F121. Further, the calculation function F122 and the calculation function F123 acquire the current calculation information D3 and the new calculation information D4 from the search function F10, respectively, and use the set charge / discharge pattern D2 to perform the battery state. Perform a simulation to calculate. The battery state includes, for example, SOC, maximum current, and maximum power, as described above.

Here, the calculation function F122 calculates the current battery state D5 using the current calculation information D3 received from the secondary battery device 11 by the search function F10. Specifically, the calculation function F122 calculates the current battery state D5 by using, for example, the current calculation algorithm D31 included in the current calculation information D3 and the current characteristic parameter D32.

Further, the calculation function F123 calculates a new battery state D6 by using the new calculation information D4. Specifically, the calculation function F12 uses, for example, the current calculation algorithm D31 included in the current calculation information D3 and the new characteristic parameter D42 included in the new calculation information D4 to obtain a new battery state. Calculate D6.

The new battery state D6 may be calculated by using, for example, a new calculation algorithm D41 included in the new calculation information D4 and a new characteristic parameter D42. Further, the new battery state D6 may be calculated by using, for example, the new calculation algorithm D41 included in the new calculation information D4 and the current characteristic parameter D32 included in the current calculation information D3.

FIG. 12 is a graph showing an example of the state change amount, which is the change amount of the battery state. The calculation function F124 calculates, for example, the amount of state change, which is the difference between the current battery state D5 calculated by the calculation function F122 and the new battery state D6 calculated by the calculation function F123. More specifically, the state change amount includes, for example, the SOC change amount ΔSOC, which is the difference between the current SOC (a) shown in FIG. 12 and the new SOC (b).

Further, the state change amount includes, for example, a change amount of the maximum current, a change amount of the maximum power, and the like. The calculation function F124 defines, for example, the range D7 of the state change amount based on the fluctuation range of the assumed state change amount. The calculation function F124 outputs the defined state change amount range D7 to the secondary battery device 11 via, for example, the input / output unit 121. Further, the calculation function F12 outputs, for example, the new calculation information D4 used in the calculation function F123 to the secondary battery device 11 via the input / output unit 121 together with the state change amount range D7 as update information. As a result, the process P4 shown in FIG. 10 is completed.

FIG. 13 is a flow chart illustrating an example of the processing flow of the state calculation unit 116 of the secondary battery device 11. When the state calculation unit 116 starts the process shown in FIG. 13, first, the state calculation unit 116 executes the process P5 for determining whether or not the update information has been received from the management device 12. Specifically, in the process P5, the state calculation unit 116 determines, for example, whether or not the update information has been received from the management device 12 by the reception function F1 shown in FIG. When the reception function F1 determines in the process P5 that the update information has not been received (NO), for example, the process shown in FIG. 13 ends.

On the other hand, if it is determined in the process P5 that the reception function F1 has received the update information (YES), the state calculation unit 116 executes, for example, the process P6 for recording the update information. In this process P6, the storage function F3 or F5 stores the update information received by the reception function F1 in the second storage area of the storage device of the state calculation unit 116. This second storage area is a storage area different from the first storage area of the storage device of the state calculation unit 116 in which the current calculation information used by the calculation function F6 for the calculation is stored. With the above, the process P6 is completed.

Next, the state calculation unit 116 executes, for example, the process P7 for calculating the current battery state. In this process P7, the state calculation unit 116 uses, for example, the current calculation information stored in the first storage area of the storage device by the storage function F2 and the storage function F4 to obtain the current battery state by the calculation function F6. calculate. The current battery state calculated here is output to, for example, the battery management unit 115 shown in FIG. 2 and used for controlling the cell group 111, and the control device 6 shown in FIG. 1 via the information output terminal 118. And output to the management device 12. As a result, the process P7 is completed.

Further, the state calculation unit 116 executes, for example, the process P8 for calculating a new battery state in parallel with the process P7. In this process P8, the state calculation unit 116 is newly operated by the calculation function F6, for example, by using the update information which is the new calculation information stored in the second storage area of the storage device by the storage function F3 and the storage function F5. Calculate the battery status of. With the above, the process P8 is completed.

Next, the state calculation unit 116 executes, for example, the process P9 for calculating the amount of change in the state. In this process P9, the state calculation unit 116 acquires the current battery state and the new battery state from the calculation function F6 by, for example, the battery state determination function F8, and sets the current battery state and the new battery state. The amount of state change, which is the difference, is calculated. Processing P9 is completed by the above.

Next, the state calculation unit 116 executes, for example, the process P10 for determining whether or not the amount of state change is within the specified range. In this process P10, the state calculation unit 116 acquires, for example, a predetermined range of the state change amount received by the reception function F1 together with the update information from the management device 12 by the determination function F8. Further, the determination function F8 determines whether or not the amount of state change calculated by the process P9 is within the specified range acquired from the reception function F1.

When the determination function F8 determines in the process P10 that the amount of state change calculated in the process P9 is not within the specified range (NO), the state calculation unit 116 ends the process shown in FIG. On the other hand, in the process P10, when the determination function F8 determines that the state change amount calculated in the process P9 is within the specified range (YES), the state calculation unit 116 executes the process P11 for updating the calculation information. ..

In this process P11, the state calculation unit 116 notifies the reception function F1 of the determination result by, for example, the determination function F8. When the determination result is notified from the determination function F8, the reception function F1 outputs the update information received from the management device 12 to the storage function F2 or the storage function F4. The storage function F2 or the storage function F4 stores the update information input from the reception function F1 in the first storage area of the storage device of the state calculation unit 116, overwrites the calculation information, and updates the information. As a result, the process shown in FIG. 13 is completed.

As described above, after the calculation information stored in the first area of the storage device of the state calculation unit 116 is updated by the process shown in FIG. 13, this new calculation information is used by the calculation function F6 to be more accurate. The new battery status is calculated. In the process P11, it is not necessary to overwrite and update the calculation information stored in the first storage area of the storage device of the state calculation unit 116.

For example, in the process P11, the calculation information stored in the first storage area of the storage device remains as it is, and the update information stored in the second storage area of the storage device is set to be used as the calculation information. Information may be updated. An example of the case where such processing P11 is adopted will be described with reference to FIG.

FIG. 14 is a flow chart showing a modified example of the processing flow of the state calculation unit 116 of FIG. In FIG. 14, the same processing as that shown in FIG. 13 is designated by the same reference numerals and the description thereof will be omitted. In the example shown in FIG. 14, in the process P11, the state calculation unit 116 uses, for example, the update information stored in the second storage area of the storage device by the storage function F3 and the storage function F5 by the calculation function F6 as the calculation information. Set to update the calculation information.

Next, the state calculation unit 116 determines, for example, whether or not an abnormality or warning such as overcharge, overdischarge, or excessive high temperature has occurred in the cell group 111 by the determination function F8 over a predetermined time. Execute P12.

When the determination function F8 determines in the process P12 that an abnormality or a warning has occurred (YES), the state calculation unit 116 executes the process P13 using the calculation information before the update. In this process P13, the state calculation unit 116 sets, for example, the calculation information before the update stored in the first storage area of the storage device as the calculation information for calculating the battery state again by the calculation function F6. Then, the process shown in FIG. 14 is terminated.

On the other hand, if the determination function F8 determines in the process P12 that no abnormality or warning has occurred (NO), the state calculation unit 116 executes, for example, the process P14 for overwriting and updating the calculation information. In this process P14, the storage function F2 and the storage function F4 of the state calculation unit 116 store the update information input from the reception function F1 in the first storage area of the storage device of the state calculation unit 116, thereby performing the calculation information. Overwrite and update. As a result, the process shown in FIG. 14 is completed.

Hereinafter, the operations of the secondary battery device 11 and the secondary battery system 1 of the present embodiment will be described.

Currently, global environmental problems are attracting attention. In order to prevent global warming, environment-friendly vehicles such as hybrid electric vehicles and electric vehicles have become widespread. In such eco-friendly vehicles, the power of a motor driven by the electric energy stored in a secondary battery replaces part or all of the power of a conventional engine.

In the electric power field, renewable energies such as photovoltaic power generation, which does not emit greenhouse gases, are attracting attention and are being introduced. Since the output of photovoltaic power generation fluctuates greatly depending on the weather, it may cause voltage fluctuations and frequency fluctuations in the power system. Therefore, as shown in FIG. 1, the photovoltaic power generation system PGS is provided with a secondary battery system 1 that suppresses fluctuation suppression of voltage and the like, and the secondary battery system 1 is charged and discharged to supply the power system 3. The output is smoothed.

In this way, secondary batteries are frequently used in systems that enable the prevention of environmental warming, and it is expected that the scope of application of secondary batteries will continue to expand in the future. In a system to which a secondary battery is applied, if the required performance of the secondary battery in the system cannot be satisfied, or if the specified number of years of use has passed, it is determined that the life of the secondary battery has expired, and a new battery is used. Will be exchanged. In the future, it is expected that the reuse of secondary batteries will accelerate, for example, the used secondary batteries removed from eco-friendly vehicles will be diverted to other uses.

There are various types of secondary batteries, such as lead batteries, nickel-metal hydride batteries, and lithium-ion secondary batteries. Among them, the lithium ion secondary battery is particularly excellent in output and energy performance, so its application range is expanding. As specifications for guaranteeing the operation of the lithium ion secondary battery, for example, a usable temperature range, a voltage range and a charge state range, and a maximum charge / discharge current are specified.

If the battery is used outside the range specified as such a specification, the battery is significantly deteriorated, and in the worst case, the battery may be damaged. Therefore, the secondary battery device 11 constituting the secondary battery system 1 has a state calculation unit 116 for calculating the battery state. The state calculation unit 116 detects the SOC and SOH of the secondary battery, the current and power that can be charged and discharged to the maximum, the presence or absence of an abnormality, and characteristic information.

In the conventional battery deterioration calculation device described in Patent Document 1, the battery usage history data stored in the non-volatile memory of the control unit of the secondary battery device is received by the receiving unit, and the battery deterioration calculation unit receives the battery capacity in advance. And the battery capacity is calculated according to the battery deterioration by combining with the battery deterioration tendency data calculated by using the temperature as a parameter. Here, this conventional battery deterioration calculation device is characterized in that the battery capacity calculation algorithm and the like can be freely updated without time constraints. In updating such an algorithm, if there is a function to determine whether the updated information is appropriate information, it is considered that a secondary battery device capable of more reliable control can be realized.

On the other hand, in the secondary battery device 11 of the present embodiment, as described above, the cell group 111 which is a secondary battery and the current sensor 113 as a detection unit which detects the voltage, current and temperature of the secondary battery , A temperature sensor 114, and a battery management unit 115. Further, the secondary battery device 11 includes a state calculation unit 116 that calculates the battery state based on the detection result of the detection unit. Further, the state calculation unit 116 has a storage device and a processing device. The storage device of the state calculation unit 116 has a first storage area for storing calculation information for calculating the battery state and a second storage area for storing update information for updating the calculation information. .. Further, the processing device of the state calculation unit 116 executes the state detection process, the update verification process, and the update process. The state detection process is a process P7 that calculates the current battery state using the calculation information. The update verification process is P8 for calculating a new battery state using update information and P9 for calculating a state change amount between the current battery state and the new battery state. The update process is process P11 for storing the update information in the first storage area and updating the calculation information when the amount of state change between the current battery state and the new battery state is within the specified range. ..

With such a configuration, the secondary battery device 11 of the present embodiment can more reliably perform control according to the state of the secondary batteries constituting the cell group 111. Specifically, the state calculation unit 116 of the secondary battery device 11 stores calculation information for calculating the battery state of the secondary battery in the first storage area of the storage device. The calculation information includes, for example, a characteristic parameter of the secondary battery and a calculation algorithm for calculating the battery state using the characteristic parameter. As described above, the battery state includes, for example, SOC, SOH, maximum power or current that can be input / output, presence / absence of abnormality, and the like. Then, the state calculation unit 116 can acquire the update information for updating the calculation information from the management device 12 and store it in the second storage area of the storage device, for example, according to the deterioration of the secondary battery. .. Then, the state calculation unit 116 calculates the current battery state using the current calculation information by the state detection process, calculates a new battery state using the update information by the update verification process, and calculates the current battery state and the new battery state. Calculate the amount of change in state with the battery state of. Further, the state calculation unit 116 stores the update information in the first storage area only when the amount of state change between the current battery state and the new battery state is within the specified range by the update process. Update the calculation information. Therefore, according to the secondary battery device 11 of the present embodiment, it is possible to prevent the calculation information from being overwritten by the update information having a problem, and to more reliably perform the control according to the state of the secondary battery. become.

Further, in the secondary battery device 11 of the present embodiment, the update process by the processing device of the state calculation unit 116 may include a change amount determination process, a temporary update process, an abnormality determination process, and an actual update process. .. As shown in FIG. 14, the change amount determination process is the process P10 for determining whether or not the state change amount is within the specified range. Further, the temporary update process is a process P11 for setting the updated battery state in the output of the state calculation unit over a predetermined period when the amount of state change is within the specified range. The abnormality determination process is the process P12 for determining the presence or absence of an abnormality over a predetermined period. The actual update process is the process P14 of storing the update information in the first storage area of the storage device and updating the calculation information when it is determined in the abnormality determination process that there is no abnormality.

With such a configuration, in addition to the above-mentioned effects, the secondary battery device 11 can use the update information as the calculation information for a limited period of time, and if there is no abnormality, the calculation information can be overwritten by the update information. .. Therefore, according to the secondary battery device 11, it is possible to more reliably perform control according to the state of the secondary batteries constituting the cell group 111.

Further, in the secondary battery device 11 of the present embodiment, the calculation information includes the characteristic parameters of the secondary battery. With such a configuration, the state calculation unit 116 acquires new characteristic parameters as update information from the management device 12, stores them in the second storage area of the storage device, and stores them in the first storage device of the storage device. Characteristic parameters can be updated with new characteristic parameters.

Further, in the secondary battery device 11 of the present embodiment, the characteristic parameters are the internal resistance R of the single battery constituting the secondary battery, the open circuit voltage OCV, the polarization resistance Rp and the capacitance C which is the capacitance of the capacitor, and the full charge. Includes capacitance Qmax. With such a configuration, according to the secondary battery device 11 of the present embodiment, characteristic parameters for which it is difficult to obtain the current value in real time during use are acquired from the management device 12 as update information, and the characteristic parameters are obtained. Can be updated. Although the update of the characteristic parameter has been described above, the update process is also applied to the calculation algorithm.

Further, the secondary battery system 1 of the present embodiment includes the above-mentioned secondary battery device 11 and a management device 12 communicatively connected to the secondary battery device 11. The management device 12 includes a storage device and a processing device. As described above, the storage device of the management device 12 stores a plurality of calculation information. Further, the processing device of the management device 12 selects one calculation information from a plurality of calculation information stored in the storage device of the management device 12 based on the information acquired from the secondary battery device 11, and updates the information. Is output to the secondary battery device 11. Further, the processing device of the management device 12 defines the range of the state change amount between the current battery state and the new battery state of the secondary battery device 11, and outputs the output to the secondary battery device 11.

With such a configuration, the storage device of the management device 12 can store a plurality of characteristic parameters as a plurality of calculation information, for example, for various historical information of the battery. Here, as described above, the characteristic parameters include the characteristic parameters of the battery for which it is difficult to obtain the current value in real time while the secondary battery device 11 is in use. The characteristic parameters of the battery for which it is difficult to obtain the current value in real time while using the secondary battery device 11 are, for example, the full charge capacity Qmax, the relationship between the open circuit voltage OCV and SOC, the polarization resistance Rp and the capacitance C, and the battery. Includes the relationship between the resistance increase rate SOHR and the capacitance maintenance rate SOHQ.

That is, after the operation of the secondary battery system 1 is started, the above-mentioned battery test is carried out in parallel, the battery is deteriorated under various conditions, the calculation information including the characteristic parameters of the battery is specified, and the plurality of calculation information is obtained. It can be stored in the storage device of the management device 12. As a result, the preparation period required for the operation of the secondary battery system 1 can be significantly reduced. Further, in the above-mentioned battery test, by carrying out a battery test in which deterioration is accelerated compared to the actual operation of the battery, the storage device of the management device 12 stores the deterioration characteristics of the battery in anticipation of the actual state of the secondary battery system 1. It is possible to memorize it. That is, while shortening the preparation period until the start of operation of the secondary battery system 1, the calculation information stored in the storage device of the management device 12 is used to store the characteristic change due to the deterioration of the battery that occurs after the operation of the secondary battery system 1. It can be reflected in the control of the secondary battery device 11.

Further, the processing device of the management device 12 acquires information including the history information of the battery from the secondary battery device 11, and in accordance with the history information, among a plurality of calculation information stored in the storage device of the management device 12. It is possible to select one calculation information from the above and output it as update information to the secondary battery device 11. As a result, the secondary battery device 11 obtains parameters from the management device 12 from the management device 12 at any time according to the history information of the battery, which is difficult to obtain the current value in real time while the secondary battery device 11 is in use. Can be done. Further, the processing device of the management device 12 defines the range of the state change amount between the current battery state and the new battery state of the secondary battery device 11, and outputs the output to the secondary battery device 11. As a result, the processing device of the secondary battery device 11 can execute the above-mentioned update process using the specified range of the state change amount acquired from the management device 12.

As described above, according to the present embodiment, it is possible to provide the secondary battery device 11 and the secondary battery system 1 capable of more reliably controlling the secondary battery. The secondary battery device 11 and the secondary battery system 1 according to the present disclosure are not limited to the above-described embodiments. Hereinafter, a modified example of the secondary battery system 1 of the above-described embodiment will be described with reference to FIG.

FIG. 15 is a functional block diagram showing a modified example of the management device 12 shown in FIG. In the secondary battery system according to this modification, the configuration of the management device 12 is different from that of the secondary battery system 1 according to the above-described embodiment. Since the other points of the secondary battery system according to this modification are the same as those of the secondary battery system according to the above-described embodiment, the same parts are designated by the same reference numerals and the description thereof will be omitted.

In the secondary battery system of this modification, the management device 12 has a function F13 for selecting a diversion destination type of the secondary battery device 11 in addition to the above-mentioned functions. Further, in the present modification, the function F11 for storing the calculation information of the management device 12 stores a plurality of history information of the secondary battery and the application destination type of the plurality of secondary battery systems 1 in the storage device of the management device 12. It has a function to store the associated diversion database. The function F13 for selecting the diversion destination type of the secondary battery device 11 determines the similarity between the history information of the secondary battery acquired from the secondary battery system 1 and the history information of the diversion database, and is based on the similarity. Select the application type of the diversion database.

As described above, in the secondary battery system according to the present modification, the storage device of the management device 12 is diverted by associating a plurality of history information of the secondary battery with the application destination type of the plurality of secondary battery systems 1. The database is stored. Then, the processing device of the management device 12 determines the similarity between the history information of the secondary battery acquired from the secondary battery device and the history information of the diversion database, and based on the similarity, the application destination type of the diversion database. Select. With this configuration, it is possible to determine the most suitable diversion destination for each secondary battery device 11 based on the history information and deterioration information of the cell group 111.

Although the embodiments of the secondary battery device and the secondary battery system according to the present disclosure have been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and the gist of the present disclosure is described. Any design changes, etc. that do not deviate are included in this disclosure.

1 Secondary battery system 11 Secondary battery device 111 Single battery group (secondary battery)
113 Current sensor (detector)
114 Temperature sensor (detector)
115 Battery management unit (detection unit)
116 Status calculation unit 12 Management device P7 Status detection processing P8 Update verification processing P11 Update processing P10 Change amount judgment processing P11 Temporary update processing P12 Abnormality judgment processing P13 Actual update processing

Claims (6)

It is a secondary battery device including a secondary battery, a detection unit that detects the voltage, current, and temperature of the secondary battery, and a state calculation unit that calculates the battery state based on the detection result of the detection unit. hand,
The state calculation unit has a storage device and a processing device, and has a storage device and a processing device.
The storage device has a first storage area for storing calculation information for calculating the battery state, and a second storage area for storing update information for updating the calculation information.
The processing device includes a state detection process for calculating the current battery state using the calculation information, an update verification process for calculating a new battery state using the update information, and the current battery state. When the amount of state change with the new battery state is within the specified range, the update process of storing the update information in the first storage area and updating the calculation information is executed. A secondary battery device characterized by. The update process includes a change amount determination process for determining whether or not the state change amount is within the range, and the updated battery state when the state change amount is within the range for a predetermined period. Temporary update processing set in the output of the state calculation unit, abnormality determination processing for determining the presence or absence of an abnormality over the predetermined period, and when it is determined that there is no abnormality in the abnormality determination processing, the update information is stored in the first storage area. The secondary battery device according to claim 1, further comprising an actual update process of storing the calculation information in the battery and updating the calculation information. The secondary battery device according to claim 1, wherein the calculation information is a characteristic parameter of the secondary battery or a calculation processing content. The characteristic parameters include the internal resistance of the cell constituting the secondary battery, the open circuit voltage, the resistance value of the parallel connection portion of the resistance and the capacitor in the equivalent circuit, the capacity of the capacitor, and the full charge capacity. The secondary battery device according to claim 3. A secondary battery system comprising the secondary battery device according to any one of claims 1 to 4 and a management device communicatively connected to the secondary battery device.
The management device includes a storage device and a processing device, and includes a storage device and a processing device.
The storage device of the management device stores a plurality of the calculation information.
The processing device of the management device selects one of the calculation information from the plurality of calculation information based on the information acquired from the secondary battery device and outputs the update information to the secondary battery device. A secondary battery system, wherein the range of the state change amount is defined and output to the secondary battery device. The storage device of the management device stores a diversion database in which a plurality of historical information of the secondary battery and a plurality of application destination types of the secondary battery system are associated with each other.
The processing device of the management device determines the similarity between the history information of the secondary battery acquired from the secondary battery device and the history information of the diversion database, and based on the similarity, the diversion database. The secondary battery system according to claim 5, wherein the application type of the above is selected.

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