JP6807017B2

JP6807017B2 - Detection device, detection method, power storage system and program

Info

Publication number: JP6807017B2
Application number: JP2016181840A
Authority: JP
Inventors: 弥仲松; 洋幸長野; 正孝厚木; 章一郎白石
Original assignee: NEC Corp
Current assignee: NEC Corp
Priority date: 2016-09-16
Filing date: 2016-09-16
Publication date: 2021-01-06
Anticipated expiration: 2036-09-16
Also published as: JP2018044927A

Description

本発明は、検出装置、検出方法、蓄電システムおよびプログラムに関する。 The present invention relates to a detection device, a detection method, a power storage system and a program.

複数の蓄電池を具備した蓄電システムにおいて、蓄電池の電圧測定回路内の抵抗値が増加することを原因として、システム停止や容量の低下が生じることがある。その抵抗値の増加を、定電流定電圧（ＣＣ−ＣＶ）充電時の電圧値を用いて検出する方法が考えられている（例えば、特許文献１参照。）。特許文献１に記載の検出方法では、ＣＣ充電時の電圧上昇速度があらかじめ設定された基準値よりも大きく、ＣＶ充電後の開回路電圧値があらかじめ設定された基準値よりも小さな場合に抵抗値の増加を判定する。 In a power storage system including a plurality of storage batteries, the system may be stopped or the capacity may be reduced due to an increase in the resistance value in the voltage measurement circuit of the storage batteries. A method of detecting the increase in the resistance value by using the voltage value at the time of constant current constant voltage (CC-CV) charging has been considered (see, for example, Patent Document 1). In the detection method described in Patent Document 1, the resistance value is obtained when the voltage rise speed during CC charging is larger than the preset reference value and the open circuit voltage value after CV charging is smaller than the preset reference value. Judge the increase in.

特開２０１１−２５７４１１号公報Japanese Unexamined Patent Publication No. 2011-257411

特許文献１に記載されたような方法では、充電開始時から充電終了後まで抵抗値の測定が必要となる。さらに、充電終了後の開回路電圧の測定も必要となり、長い期間における測定が必要となってしまうという問題点がある。さらに、抵抗値の増加を判定するタイミングが充電終了時以降に限定されるため、充電中に過充電の誤検出等の不具合が生じても、それを充電中に検出することはできないという問題点がある。 In the method as described in Patent Document 1, it is necessary to measure the resistance value from the start of charging to the end of charging. Further, it is necessary to measure the open circuit voltage after the charging is completed, and there is a problem that the measurement is required for a long period of time. Furthermore, since the timing for determining the increase in resistance value is limited to after the end of charging, there is a problem that even if a problem such as erroneous detection of overcharging occurs during charging, it cannot be detected during charging. There is.

本発明の目的は、上述した課題を解決する検出装置、検出方法、蓄電システムおよびプログラムを提供することである。 An object of the present invention is to provide a detection device, a detection method, a power storage system, and a program that solve the above-mentioned problems.

本発明の検出装置は、
複数の蓄電池に定電流定電圧充電を行う際、前記複数の蓄電池の電圧値および該複数の蓄電池へ流れる電流値それぞれを所定の時間間隔で測定する監視部と、
前記複数の蓄電池のうち、前記監視部が測定した所定の蓄電池の電圧値が所定の電圧閾値以上であり、かつそのときに前記監視部が測定した電流値が所定の電流閾値以上である場合、該電圧値と前記複数の蓄電池の電圧値のうち最小となる最小セル電圧値とに基づいて、前記蓄電池の抵抗値が増加しているか否かを判定する判定部とを有する。
また、本発明の検出方法は、
複数の蓄電池に定電流定電圧充電を行う際、前記複数の蓄電池の電圧値および該複数の蓄電池へ流れる電流値それぞれを所定の時間間隔で測定する処理と、
前記複数の蓄電池のうち、前記測定した所定の蓄電池の電圧値が所定の電圧閾値以上であるか否かを判定する処理と、
前記所定の蓄電池の電圧値が所定の電圧閾値以上である場合に測定した電流値が所定の電流閾値以上であるか否かを判定する処理と、
前記複数の蓄電池のうち、前記所定の蓄電池の電圧値が前記電圧閾値以上であり、かつそのときに測定した電流値が前記電流閾値以上である場合、該電圧値と前記複数の蓄電池の電圧値のうち最小となる最小セル電圧値とに基づいて、前記蓄電池の抵抗値が増加しているか否かを判定する処理とを行う。
また、本発明の蓄電システムは、
複数の蓄電池と、
前記複数の蓄電池の抵抗値を検出する検出装置とを有し、
前記検出装置は、
前記複数の蓄電池に定電流定電圧充電を行う際、前記複数の蓄電池の電圧値および該複数の蓄電池へ流れる電流値それぞれを所定の時間間隔で測定する監視部と、
前記複数の蓄電池のうち、前記監視部が測定した所定の蓄電池の電圧値が所定の電圧閾値以上であり、かつそのときに前記監視部が測定した電流値が所定の電流閾値以上である場合、該電圧値と前記複数の蓄電池の電圧値のうち最小となる最小セル電圧値とに基づいて、前記蓄電池の抵抗値が増加しているか否かを判定する判定部とを有する。
また、本発明のプログラムは、
複数の蓄電池に定電流定電圧充電を行う際、前記複数の蓄電池の電圧値および該複数の蓄電池へ流れる電流値それぞれを所定の時間間隔で測定する手順と、
前記複数の蓄電池のうち、前記測定した所定の蓄電池の電圧値が所定の電圧閾値以上であるか否かを判定する手順と、
前記所定の蓄電池の電圧値が所定の電圧閾値以上である場合に測定した電流値が所定の電流閾値以上であるか否かを判定する手順と、
前記複数の蓄電池のうち、前記所定の蓄電池の電圧値が前記電圧閾値以上であり、かつそのときに測定した電流値が前記電流閾値以上である場合、該電圧値と前記複数の蓄電池の電圧値のうち最小となる最小セル電圧値とに基づいて、前記蓄電池の抵抗値が増加しているか否かを判定する手順とを実行させる。 The detection device of the present invention
When charging a plurality of storage batteries with constant current and constant voltage, a monitoring unit that measures the voltage value of the plurality of storage batteries and the current value flowing through the plurality of storage batteries at predetermined time intervals, and
When the voltage value of the predetermined storage battery measured by the monitoring unit is equal to or higher than the predetermined voltage threshold value among the plurality of storage batteries, and the current value measured by the monitoring unit at that time is equal to or higher than the predetermined current threshold value. It has a determination unit for determining whether or not the resistance value of the storage battery is increasing based on the voltage value and the minimum cell voltage value that is the minimum among the voltage values of the plurality of storage batteries.
Moreover, the detection method of this invention
When a plurality of storage batteries are charged with constant current and constant voltage, a process of measuring the voltage value of the plurality of storage batteries and the current value flowing through the plurality of storage batteries at predetermined time intervals, and
Among the plurality of storage batteries, a process of determining whether or not the measured voltage value of the predetermined storage battery is equal to or higher than a predetermined voltage threshold value.
A process of determining whether or not the measured current value is equal to or higher than the predetermined current threshold value when the voltage value of the predetermined storage battery is equal to or higher than the predetermined voltage threshold value.
Among the plurality of storage batteries, when the voltage value of the predetermined storage battery is equal to or higher than the voltage threshold value and the current value measured at that time is equal to or higher than the current threshold value, the voltage value and the voltage values of the plurality of storage batteries are obtained. A process of determining whether or not the resistance value of the storage battery is increasing is performed based on the minimum cell voltage value that is the minimum of the two.
Moreover, the power storage system of the present invention
With multiple storage batteries
It has a detection device that detects the resistance value of the plurality of storage batteries.
The detection device
When the plurality of storage batteries are charged with constant current and constant voltage, a monitoring unit that measures the voltage value of the plurality of storage batteries and the current value flowing through the plurality of storage batteries at predetermined time intervals, and
When the voltage value of the predetermined storage battery measured by the monitoring unit is equal to or higher than the predetermined voltage threshold value among the plurality of storage batteries, and the current value measured by the monitoring unit at that time is equal to or higher than the predetermined current threshold value. It has a determination unit for determining whether or not the resistance value of the storage battery is increasing based on the voltage value and the minimum cell voltage value that is the minimum among the voltage values of the plurality of storage batteries.
In addition, the program of the present invention
When charging a plurality of storage batteries with constant current and constant voltage, a procedure for measuring the voltage value of the plurality of storage batteries and the current value flowing through the plurality of storage batteries at predetermined time intervals, and
A procedure for determining whether or not the measured voltage value of the predetermined storage battery among the plurality of storage batteries is equal to or higher than the predetermined voltage threshold value.
A procedure for determining whether or not the measured current value is equal to or higher than the predetermined current threshold value when the voltage value of the predetermined storage battery is equal to or higher than the predetermined voltage threshold value.
Among the plurality of storage batteries, when the voltage value of the predetermined storage battery is equal to or higher than the voltage threshold value and the current value measured at that time is equal to or higher than the current threshold value, the voltage value and the voltage values of the plurality of storage batteries are obtained. The procedure for determining whether or not the resistance value of the storage battery is increasing is executed based on the minimum cell voltage value that is the minimum of the two.

以上説明したように、本発明においては、充電中の短い期間に測定した測定値を用いて抵抗値の増加を検出することができる。 As described above, in the present invention, the increase in resistance value can be detected by using the measured value measured in a short period during charging.

本発明の検出装置を用いた蓄電システムの第１の実施の形態を示す図である。It is a figure which shows the 1st Embodiment of the power storage system using the detection device of this invention. 図１に示した検出装置の内部構成の一例を示す図である。It is a figure which shows an example of the internal structure of the detection apparatus shown in FIG. 図１に示した蓄電システムにおける抵抗値増加の検出方法の一例を説明するためのフローチャートである。It is a flowchart for demonstrating an example of the detection method of the resistance value increase in the power storage system shown in FIG. 本発明の検出装置を用いた蓄電システムの第２の実施の形態を示す図である。It is a figure which shows the 2nd Embodiment of the power storage system using the detection device of this invention. 図４に示した検出装置の内部構成の一例を示す図である。It is a figure which shows an example of the internal structure of the detection apparatus shown in FIG. 正常時における、定電流定電圧充電を行っている蓄電池の電圧値および電流値の時間的変化の一例を示す図である。It is a figure which shows an example of the time change of the voltage value and the current value of the storage battery which performs a constant current constant voltage charge in a normal state. 抵抗値増加が生じた場合の、定電流定電圧充電を行っている蓄電池の電圧値および電流値の時間的変化の一例を示す図である。It is a figure which shows an example of the temporal change of the voltage value and the current value of the storage battery which performs a constant current constant voltage charge when a resistance value increase occurs. 図５に示した判定部における抵抗値の算出方法を説明するための図である。It is a figure for demonstrating the calculation method of the resistance value in the determination part shown in FIG. 図４に示した蓄電システムにおける抵抗値増加の検出方法の一例を説明するためのフローチャートである。It is a flowchart for demonstrating an example of the detection method of the resistance value increase in the power storage system shown in FIG. 本発明の検出装置を用いた蓄電システムの第３の実施の形態を示す図である。It is a figure which shows the 3rd Embodiment of the power storage system using the detection device of this invention. 図１２に示した検出装置の内部構成の一例を示す図である。It is a figure which shows an example of the internal structure of the detection apparatus shown in FIG. 図１０に示した蓄電システムにおける抵抗値増加の検出方法の一例を説明するためのフローチャートである。It is a flowchart for demonstrating an example of the detection method of the resistance value increase in the power storage system shown in FIG.

以下に本発明の実施の形態について図面を参照して説明する。 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

本発明を適用する蓄電システムは、複数の蓄電モジュールが、少なくとも一部が直列に接続された構成を有する。また、蓄電システムを構成する各蓄電モジュールは、１以上の蓄電池（電池セル）から構成されるものである。
（第１の実施の形態） The power storage system to which the present invention is applied has a configuration in which a plurality of power storage modules are connected in series at least in part. Further, each power storage module constituting the power storage system is composed of one or more storage batteries (battery cells).
(First Embodiment)

図１は、本発明の検出装置を用いた蓄電システムの第１の実施の形態を示す図である。
本形態は図１に示すように、検出装置１００と、複数の蓄電池２００−１〜２００−３とを有している。なお、図１には、蓄電池２００−１〜２００−３が３つである場合を例に挙げて示しているが、この数に限らない。 FIG. 1 is a diagram showing a first embodiment of a power storage system using the detection device of the present invention.
As shown in FIG. 1, this embodiment has a detection device 100 and a plurality of storage batteries 200-1 to 200-3. Note that FIG. 1 shows an example in which there are three storage batteries 200-1 to 200-3, but the number is not limited to this.

蓄電池２００−１〜２００−３は、充電および放電可能な二次電池である。検出装置１００は、蓄電池２００−１〜２００−３それぞれの電圧値および蓄電池２００−１〜２００−３に流れる電流値を測定する。なお、蓄電池２００−１〜２００−３それぞれの内部に、自身の電圧値および電流値を測定する機構が設けられている場合、検出装置１００は、それらの測定値を取得する。 The storage batteries 200-1 to 200-3 are secondary batteries that can be charged and discharged. The detection device 100 measures the voltage value of each of the storage batteries 200-1 to 200-3 and the current value flowing through the storage batteries 200-1 to 200-3. When a mechanism for measuring its own voltage value and current value is provided inside each of the storage batteries 200-1 to 200-3, the detection device 100 acquires those measured values.

図２は、図１に示した検出装置１００の内部構成の一例を示す図である。図１に示した検出装置１００は図２に示すように、監視部１１０と、判定部１２０とを有している。なお、図２には、図１に示した検出装置１００が具備する構成要素のうち、本実施の形態に関わる主要な構成要素の一例を示す。 FIG. 2 is a diagram showing an example of the internal configuration of the detection device 100 shown in FIG. As shown in FIG. 2, the detection device 100 shown in FIG. 1 has a monitoring unit 110 and a determination unit 120. Note that FIG. 2 shows an example of the main components related to the present embodiment among the components included in the detection device 100 shown in FIG.

監視部１１０は、蓄電池２００−１〜２００−３に定電流定電圧充電を行う際、蓄電池２００−１〜２００−３の電圧値それぞれを所定の時間間隔で測定または取得する。また、監視部１１０は、蓄電池２００−１〜２００−３に定電流定電圧充電を行う際、蓄電池２００−１〜２００−３に流れる電流値を、電圧値の測定または取得のタイミングと同じタイミングで測定または取得する。このとき、監視部１１０は、蓄電池２００−１〜２００−３から構成される蓄電システム全体における電流値を、電圧値の測定または取得のタイミングと同じタイミングで測定または取得するものであっても良い。
判定部１２０は、蓄電池２００−１〜２００−３のうち、所定の蓄電池の電圧値が所定の電圧閾値以上であるかどうかを判定する。また、判定部１２０は、所定の蓄電池の電圧値が所定の電圧閾値以上である場合に、監視部１１０が測定した電流値が所定の電流閾値以上であるかどうかを判定する。判定部１２０は、所定の蓄電池の電圧値が所定の電圧閾値以上であり、かつそのときに監視部１１０が測定した電流値が所定の電流閾値以上である場合、その電圧値とそのときの蓄電池２００−１〜２００−３の電圧値のうち最小となる最小セル電圧値とに基づいて、所定の蓄電池の抵抗値が増加しているか否かを判定する。具体的には、判定部１２０は、所定の蓄電池の電圧値と最小セル電圧値との電圧差ΔＶと、電圧差閾値とを比較し、その比較結果に基づいて、抵抗値が増加しているか否かを判定する。このとき、判定部１２０は、電圧差ΔＶが電圧差閾値以上である場合、抵抗値が増加していると判定する。 When the storage batteries 200-1 to 200-3 are charged with a constant current and a constant voltage, the monitoring unit 110 measures or acquires the voltage values of the storage batteries 200-1 to 200-3 at predetermined time intervals. Further, when the monitoring unit 110 charges the storage batteries 200-1 to 200-3 with a constant current and a constant voltage, the monitoring unit 110 sets the current value flowing through the storage batteries 200-1 to 200-3 at the same timing as the timing of measuring or acquiring the voltage value. To measure or obtain at. At this time, the monitoring unit 110 may measure or acquire the current value in the entire power storage system composed of the storage batteries 200-1 to 200-3 at the same timing as the timing of measuring or acquiring the voltage value. ..
The determination unit 120 determines whether or not the voltage value of the predetermined storage battery among the storage batteries 200-1 to 200-3 is equal to or higher than the predetermined voltage threshold value. Further, the determination unit 120 determines whether or not the current value measured by the monitoring unit 110 is equal to or greater than the predetermined current threshold value when the voltage value of the predetermined storage battery is equal to or greater than the predetermined voltage threshold value. When the voltage value of the predetermined storage battery is equal to or higher than the predetermined voltage threshold value and the current value measured by the monitoring unit 110 is equal to or higher than the predetermined current threshold value, the determination unit 120 determines the voltage value and the storage battery at that time. It is determined whether or not the resistance value of the predetermined storage battery is increasing based on the minimum cell voltage value which is the minimum among the voltage values of 200-1 to 200-3. Specifically, the determination unit 120 compares the voltage difference ΔV between the voltage value of the predetermined storage battery and the minimum cell voltage value with the voltage difference threshold value, and based on the comparison result, is the resistance value increased? Judge whether or not. At this time, when the voltage difference ΔV is equal to or greater than the voltage difference threshold value, the determination unit 120 determines that the resistance value is increasing.

以下に、図１に示した蓄電システムにおける抵抗値増加の検出方法について説明する。図３は、図１に示した蓄電システムにおける抵抗値増加の検出方法の一例を説明するためのフローチャートである。 The method of detecting the increase in resistance value in the power storage system shown in FIG. 1 will be described below. FIG. 3 is a flowchart for explaining an example of a method for detecting an increase in resistance value in the power storage system shown in FIG.

まず、蓄電池２００−１〜２００−３に対して定電流定電圧充電を開始する（ステップＳ１）。すると、監視部１１０は、蓄電池２００−１〜２００−３の電圧値それぞれを、また蓄電池２００−１〜２００−３に流れる電流値を所定の時間間隔で測定する（ステップＳ２）。
続いて、判定部１２０は、蓄電池２００−１〜２００−３のうち、所定の蓄電池の電圧値があらかじめ設定された電圧閾値以上であり、かつそのときに監視部１１０が測定した電流値があらかじめ設定された電流閾値以上であるかどうかを判定する（ステップＳ３）。所定の蓄電池の電圧値が所定の電圧閾値以上であり、かつそのときに監視部１１０が測定した電流値が所定の電流閾値以上である場合、判定部１２０は、その電圧値とそのときの蓄電池２００−１〜２００−３の電圧値のうち最小となる最小セル電圧値とに基づいて、抵抗値が増加しているか否かを判定する（ステップＳ４）。このとき、判定部１２０は、所定の蓄電池の電圧値と最小セル電圧値との電圧差ΔＶとあらかじめ設定された電圧差閾値とを比較し、その比較結果に基づいて、抵抗値が増加しているか否かを判定するものであっても良い。 First, constant current and constant voltage charging is started for the storage batteries 200-1 to 200-3 (step S1). Then, the monitoring unit 110 measures each of the voltage values of the storage batteries 200-1 to 200-3 and the current value flowing through the storage batteries 200-1 to 200-3 at predetermined time intervals (step S2).
Subsequently, in the determination unit 120, among the storage batteries 200-1 to 200-3, the voltage value of the predetermined storage battery is equal to or higher than the preset voltage threshold value, and the current value measured by the monitoring unit 110 at that time is predetermined. It is determined whether or not it is equal to or higher than the set current threshold (step S3). When the voltage value of the predetermined storage battery is equal to or higher than the predetermined voltage threshold value and the current value measured by the monitoring unit 110 is equal to or higher than the predetermined current threshold value, the determination unit 120 determines the voltage value and the storage battery at that time. It is determined whether or not the resistance value is increased based on the minimum cell voltage value which is the minimum among the voltage values of 200-1 to 200-3 (step S4). At this time, the determination unit 120 compares the voltage difference ΔV between the voltage value of the predetermined storage battery and the minimum cell voltage value with the preset voltage difference threshold value, and the resistance value increases based on the comparison result. It may be used to determine whether or not it is present.

このように、蓄電池の電圧値が所定の電圧閾値以上となり、かつそのときの電流値が所定の電流閾値以上となった時の電圧値と最小セル電圧値と基づいて、抵抗値が増加しているかどうかを判定する。そのため、充電中の短い期間に測定した測定値を用いて抵抗値の増加を検出することができる。
（第２の実施の形態） In this way, the resistance value increases based on the voltage value and the minimum cell voltage value when the voltage value of the storage battery becomes the predetermined voltage threshold value or more and the current value at that time becomes the predetermined current threshold value or more. Determine if it is present. Therefore, the increase in resistance value can be detected by using the measured value measured in a short period during charging.
(Second Embodiment)

図４は、本発明の検出装置を用いた蓄電システムの第２の実施の形態を示す図である。
本形態は図４に示すように、検出装置１０１と、複数の蓄電池２０１−１〜２０１−３とを有している。なお、図４には、蓄電池２０１−１〜２０１−３が３つである場合を例に挙げて示しているが、この数に限らない。 FIG. 4 is a diagram showing a second embodiment of a power storage system using the detection device of the present invention.
As shown in FIG. 4, this embodiment has a detection device 101 and a plurality of storage batteries 201-1 to 201-3. Note that FIG. 4 shows an example in which there are three storage batteries 201-1 to 201-3, but the number is not limited to this.

蓄電池２０１−１〜２０１−３は、充電および放電可能な二次電池である。検出装置１０１は、蓄電池２０１−１〜２０１−３の電圧値および蓄電池２０１−１〜２０１−３に流れる電流値を測定する。なお、蓄電池２０１−１〜２０１−３それぞれの内部に、自身の電圧値および電流値を測定する機構が設けられている場合、検出装置１０１は、それらの測定値を取得する。 The storage batteries 201-1 to 201-3 are secondary batteries that can be charged and discharged. The detection device 101 measures the voltage value of the storage batteries 201-1 to 201-3 and the current value flowing through the storage batteries 201-1 to 201-3. If a mechanism for measuring its own voltage value and current value is provided inside each of the storage batteries 201-1 to 201-3, the detection device 101 acquires those measured values.

図５は、図４に示した検出装置１０１の内部構成の一例を示す図である。図４に示した検出装置１０１は図５に示すように、監視部１１１と、判定部１２１と、記憶部１３１とを有している。なお、図５には、図４に示した検出装置１０１が具備する構成要素のうち、本実施の形態に関わる主要な構成要素の一例を示す。 FIG. 5 is a diagram showing an example of the internal configuration of the detection device 101 shown in FIG. As shown in FIG. 5, the detection device 101 shown in FIG. 4 has a monitoring unit 111, a determination unit 121, and a storage unit 131. Note that FIG. 5 shows an example of the main components related to the present embodiment among the components included in the detection device 101 shown in FIG.

監視部１１１は、蓄電池２０１−１〜２０１−３に定電流定電圧充電を行う際、蓄電池２０１−１〜２０１−３の電圧値それぞれを所定の時間間隔で測定または取得する。また、監視部１１１は、蓄電池２０１−１〜２０１−３に定電流定電圧充電を行う際、蓄電池２０１−１〜２０１−３に流れる電流値を、電圧値の測定または取得のタイミングと同じタイミングで測定または取得する。このとき、監視部１１１は、蓄電池２０１−１〜２０１−３から構成される蓄電システム全体における電流値を、電圧値の測定または取得のタイミングと同じタイミングで測定または取得するものであっても良い。
記憶部１３１は、監視部１１１が測定または取得した電圧値と電流値とを対応付けて記憶する。なお、記憶部１３４は、監視部１１４が測定または取得した電圧値と電流値との対応付けすべてを記憶する必要はなく、各測定時刻における電圧値の最大値（最大セル電圧値）と最小値（最小セル電圧値）と電流値との対応付けのみを記憶すれば良い。
判定部１２１は、監視部１１１が測定した、最大セル電圧値があらかじめ設定された電圧閾値以上の値であって、電流値があらかじめ設定された電流閾値以上の値であるかどうかを判定する。判定部１２１は、監視部１１１が測定した、最大セル電圧値があらかじめ設定された電圧閾値以上の値であって、電流値があらかじめ設定された電流閾値以上の値である場合、蓄電池２０１−１〜２０１−３のうち、その電流値と、その最大セル電圧値と、そのときの最小セル電圧値とに基づいて、最大蓄電池の抵抗値を算出する。この抵抗値の算出方法について、具体的に説明する。 When the storage batteries 201-1 to 201-3 are charged with a constant current and a constant voltage, the monitoring unit 111 measures or acquires the voltage values of the storage batteries 201-1 to 201-3 at predetermined time intervals. Further, when the monitoring unit 111 charges the storage batteries 201-1 to 201-3 with a constant current and constant voltage, the monitoring unit 111 sets the current value flowing through the storage batteries 201-1 to 201-3 at the same timing as the timing of measuring or acquiring the voltage value. To measure or obtain at. At this time, the monitoring unit 111 may measure or acquire the current value in the entire power storage system composed of the storage batteries 201-1 to 201-3 at the same timing as the timing of measuring or acquiring the voltage value. ..
The storage unit 131 stores the voltage value measured or acquired by the monitoring unit 111 in association with the current value. The storage unit 134 does not need to store all the correspondence between the voltage value measured or acquired by the monitoring unit 114 and the current value, and the maximum value (maximum cell voltage value) and the minimum value of the voltage value at each measurement time. Only the correspondence between (minimum cell voltage value) and current value needs to be stored.
The determination unit 121 determines whether or not the maximum cell voltage value measured by the monitoring unit 111 is a value equal to or higher than a preset voltage threshold value and the current value is a value equal to or higher than a preset current threshold value. When the maximum cell voltage value measured by the monitoring unit 111 is equal to or higher than the preset voltage threshold value and the current value is equal to or higher than the preset current threshold value, the determination unit 121 is stored in the storage battery 2011-1. Of ~ 201-3, the resistance value of the maximum storage battery is calculated based on the current value, the maximum cell voltage value, and the minimum cell voltage value at that time. The method of calculating this resistance value will be specifically described.

図６は、正常時における、定電流定電圧充電を行っている蓄電池の電圧値および電流値の時間的変化の一例を示す図である。図６に示すように、まず定電流充電が行われ、蓄電池の電圧値が一定の電圧値になると、定電圧充電が行われる。このとき、複数の充電池は互いに電圧値の差があるため、そのうち、電圧値が最大である最大蓄電池と、電圧値が最小である最小蓄電池とが存在する。図６では、最大蓄電池の電圧値を「最大セル電圧値」と示し、最小蓄電池の電圧値を「最小セル電圧値」と示す。抵抗値が増加した蓄電池の電圧は、充電時に電圧降下分の影響で大きくなる。そのため、蓄電システムの充電時における最大セル電圧値は、その蓄電池の電圧値になる。 FIG. 6 is a diagram showing an example of a time change of a voltage value and a current value of a storage battery performing constant current constant voltage charging in a normal state. As shown in FIG. 6, constant current charging is performed first, and when the voltage value of the storage battery reaches a constant voltage value, constant voltage charging is performed. At this time, since the plurality of rechargeable batteries have different voltage values from each other, there are a maximum storage battery having the maximum voltage value and a minimum storage battery having the minimum voltage value. In FIG. 6, the voltage value of the maximum storage battery is indicated by “maximum cell voltage value”, and the voltage value of the minimum storage battery is indicated by “minimum cell voltage value”. The voltage of the storage battery with an increased resistance value increases due to the effect of the voltage drop during charging. Therefore, the maximum cell voltage value at the time of charging the power storage system is the voltage value of the storage battery.

図７は、抵抗値増加が生じた場合の、定電流定電圧充電を行っている蓄電池の電圧値および電流値の時間的変化の一例を示す図である。図７に示すように、図６に示したものと比べて、電流が流れているときの最大セル電圧値と最小セル電圧値との差が大きくなる。特に充電末期では、ＳＯＣ（ＳｔａｔｅＯｆＣｈａｒｇｅ）の変化に起因した電圧値の変化が小さくなり、内部抵抗値に起因した電圧降下の寄与が大きくなる。 FIG. 7 is a diagram showing an example of temporal changes in the voltage value and the current value of the storage battery performing constant current constant voltage charging when the resistance value increases. As shown in FIG. 7, the difference between the maximum cell voltage value and the minimum cell voltage value when a current is flowing is larger than that shown in FIG. In particular, at the end of charging, the change in the voltage value due to the change in SOC (State Of Charge) becomes small, and the contribution of the voltage drop due to the internal resistance value becomes large.

本形態においては、この充電末期において、電圧値に基づいて抵抗値を算出することで、抵抗値増加を検知する。 In this embodiment, the increase in resistance value is detected by calculating the resistance value based on the voltage value at the end of charging.

図８は、図５に示した判定部１２１における抵抗値の算出方法を説明するための図である。図８に示すように、本形態においては、判定部１２１は、最大セル電圧値があらかじめ設定された電圧値Ｖｔｈ（満充電電圧値よりも１００〜数１００ｍＶ小さな値：電圧閾値）以上の値であって、電流値があらかじめ設定された、例えば８Ａ程度の電流値Ｉｔｈ（充電電流値の最大値よりもやや小さな値：電流閾値）以上の値である期間（図８に示した時刻ｔ２からｔ３までの期間）を充電末期とする。判定部１２１は、この期間において抵抗値を算出し、抵抗値増加を検出することができる。 FIG. 8 is a diagram for explaining a method of calculating the resistance value in the determination unit 121 shown in FIG. As shown in FIG. 8, in the present embodiment, the determination unit 121 has a maximum cell voltage value equal to or higher than a preset voltage value Vth (a value 100 to several hundred mV smaller than the full charge voltage value: voltage threshold value). Therefore, a period (time t2 to t3 shown in FIG. 8) in which the current value is equal to or larger than a preset current value Is (a value slightly smaller than the maximum value of the charging current value: current threshold value) of, for example, about 8 A. The period up to) is the end of charging. The determination unit 121 can calculate the resistance value during this period and detect the increase in the resistance value.

判定部１２１は、上記期間において、最大蓄電池の電圧値を用いて抵抗値を算出する。判定部１２１は、以下の式を用いて抵抗値を算出する。
抵抗値＝（最大セル電圧値−最小セル電圧値）／電流値…（式１）
判定部１２１は、算出した抵抗値が、セルが劣化したときの抵抗値（抵抗閾値）よりも大きな値である場合、抵抗値が増加したと判定する。このセルが劣化したときの抵抗値は、過去の運用履歴や実験等で得られた値であって、あらかじめ設定されている閾値である。例えば、判定部１２１は、電流が８Ａ以上、最大セル電圧値が４Ｖ以上の条件を満たすデータ点での抵抗相当値の平均値を算出し、算出した値が５ｍΩ以上になった場合、抵抗値増加を検知する。このとき、抵抗値増加が生じている蓄電システムの１７台中１７台を検知することができる。 The determination unit 121 calculates the resistance value using the voltage value of the maximum storage battery in the above period. The determination unit 121 calculates the resistance value using the following formula.
Resistance value = (maximum cell voltage value-minimum cell voltage value) / current value ... (Equation 1)
When the calculated resistance value is larger than the resistance value (resistance threshold value) when the cell deteriorates, the determination unit 121 determines that the resistance value has increased. The resistance value when this cell deteriorates is a value obtained in a past operation history, an experiment, or the like, and is a preset threshold value. For example, the determination unit 121 calculates the average value of the resistance equivalent values at the data points satisfying the conditions of the current of 8 A or more and the maximum cell voltage value of 4 V or more, and when the calculated value becomes 5 mΩ or more, the resistance value. Detect an increase. At this time, 17 out of 17 power storage systems in which the resistance value is increased can be detected.

以下に、図４に示した蓄電システムにおける抵抗値増加の検出方法について説明する。図９は、図４に示した蓄電システムにおける抵抗値増加の検出方法の一例を説明するためのフローチャートである。 The method of detecting the increase in resistance value in the power storage system shown in FIG. 4 will be described below. FIG. 9 is a flowchart for explaining an example of a method for detecting an increase in resistance value in the power storage system shown in FIG.

まず、検出装置１０１は、検出装置１０１が具備しているカウンタ（不図示）の値をリセットして「０」とする。続いて、蓄電池２０１−１〜２０１−３に対して定電流定電圧充電を開始する（ステップＳ１１）。すると、監視部１１１は、蓄電池２０１−１〜２０１−３の電圧値それぞれを、また蓄電池２０１−１〜２０１−３に流れる電流値を所定の時間間隔で測定する（ステップＳ１２）。
続いて、判定部１２１は、監視部１１１が測定した、最大セル電圧値があらかじめ設定された電圧閾値以上の値であって、電流値があらかじめ設定された電流閾値以上の値であるかどうかを判定する（ステップＳ１３）。最大セル電圧値があらかじめ設定された電圧閾値以上の値であって、電流値があらかじめ設定された電流閾値以上の値である場合、判定部１２１は、検出装置１０１が具備しているカウンタの値を「１」とする（ステップＳ１４）。すると、判定部１２１は、そのときの最大セル電圧値と、最小セル電圧値と、電流値とを対応付けて記憶部１３１に記憶させる（ステップＳ１５）。その後、さらに、監視部１１１は、ステップＳ１２の処理を行う。判定部１２１は、最大セル電圧値と最小セル電圧値と電流値とを記憶部１３１に記憶させる際、最大セル電圧値と最小セル電圧値と電流値とが記憶部１３１にすでに記憶されている場合、すでに記憶されている値の上に、上書き処理を行う。また、判定部１２１は、上書き処理を行うのではなく、複数の最大セル電圧値と最小セル電圧値と電流値とを記憶部１３１に記憶させても良い。
一方、ステップＳ１３にて、最大セル電圧値があらかじめ設定された電圧閾値以上の値ではない、または電流値があらかじめ設定された電流閾値以上の値ではない場合、判定部１２１は、カウンタの値が「１」であるかどうかを判定する（ステップＳ１６）。カウンタの値が「１」ではない場合、さらに、監視部１１１は、ステップＳ１２の処理を行う。
ステップＳ１６にて、カウンタの値が「１」である場合、判定部１２１は、記憶部１３１が記憶している電流値と、最大セル電圧値と、最小セル電圧値とに基づいて、（式１）を用いて、最大蓄電池の抵抗値を算出する（ステップＳ１７）。判定部１２１は、記憶部１３１に複数の電流値と、最大セル電圧値と、最小セル電圧値とが記憶されている場合には、判定に使用する電流値と、最大セル電圧値と、最小セル電圧値とを選択し、最大蓄電池の抵抗値を算出しても良い。判定部１２１は、最大セル電圧値の値が最も大きな値となる時間の電流値と最大セル電圧値と最小セル電圧値とを選択しても良いし、最大セル電圧値と最小セル電圧値との電位差が最も大きな値となる時間の電流値と最大セル電圧値と最小セル電圧値とを選択しても良い。すると、判定部１２１は、算出した抵抗値と、あらかじめ設定されている抵抗閾値とに基づいて、抵抗値が増加しているかどうかを判定する（ステップＳ１８）。具体的には、判定部１２１は、算出した抵抗値が、セルが劣化したときの抵抗値（抵抗閾値）よりも大きな値である場合、抵抗値が増加したと判定する。 First, the detection device 101 resets the value of the counter (not shown) included in the detection device 101 to "0". Subsequently, constant current and constant voltage charging is started for the storage batteries 201-1 to 201-3 (step S11). Then, the monitoring unit 111 measures each of the voltage values of the storage batteries 201-1 to 201-3 and the current value flowing through the storage batteries 201-1 to 201-3 at predetermined time intervals (step S12).
Subsequently, the determination unit 121 determines whether or not the maximum cell voltage value measured by the monitoring unit 111 is a value equal to or higher than the preset voltage threshold value and the current value is equal to or higher than the preset current threshold value. Determine (step S13). When the maximum cell voltage value is equal to or higher than the preset voltage threshold value and the current value is equal to or higher than the preset current threshold value, the determination unit 121 determines the value of the counter provided in the detection device 101. Is set to "1" (step S14). Then, the determination unit 121 stores the maximum cell voltage value, the minimum cell voltage value, and the current value at that time in the storage unit 131 in association with each other (step S15). After that, the monitoring unit 111 further performs the process of step S12. When the determination unit 121 stores the maximum cell voltage value, the minimum cell voltage value, and the current value in the storage unit 131, the maximum cell voltage value, the minimum cell voltage value, and the current value are already stored in the storage unit 131. In that case, overwrite processing is performed on the already stored value. Further, the determination unit 121 may store a plurality of maximum cell voltage values, minimum cell voltage values, and current values in the storage unit 131 instead of performing the overwrite process.
On the other hand, in step S13, when the maximum cell voltage value is not equal to or higher than the preset voltage threshold value or the current value is not equal to or higher than the preset current threshold value, the determination unit 121 determines that the counter value is set. It is determined whether or not it is "1" (step S16). If the value of the counter is not "1", the monitoring unit 111 further performs the process of step S12.
When the value of the counter is "1" in step S16, the determination unit 121 determines (formula) based on the current value stored in the storage unit 131, the maximum cell voltage value, and the minimum cell voltage value. 1) is used to calculate the resistance value of the maximum storage battery (step S17). When a plurality of current values, a maximum cell voltage value, and a minimum cell voltage value are stored in the storage unit 131, the determination unit 121 uses the current value, the maximum cell voltage value, and the minimum cell voltage value for determination. You may select the cell voltage value and calculate the resistance value of the maximum storage battery. The determination unit 121 may select the current value, the maximum cell voltage value, and the minimum cell voltage value at the time when the maximum cell voltage value becomes the largest value, or the maximum cell voltage value and the minimum cell voltage value. The current value, the maximum cell voltage value, and the minimum cell voltage value at the time when the potential difference of the above becomes the largest value may be selected. Then, the determination unit 121 determines whether or not the resistance value is increasing based on the calculated resistance value and the preset resistance threshold value (step S18). Specifically, the determination unit 121 determines that the resistance value has increased when the calculated resistance value is larger than the resistance value (resistance threshold value) when the cell deteriorates.

なお、図５に示した記憶部１３１が、電圧値および電流値を記憶する場合、蓄電池を識別できる識別情報と対応付けて記憶するものであっても良い。こうすることで、抵抗値が増加している電圧値の蓄電池を特定することが可能となる。また、記憶部１３１が電圧値および電流値を記憶する時刻の範囲は閾値に対応した範囲を含んでいれば、その範囲の広さは限定しない。また、その範囲は、複数の範囲に分かれていてもよい When the storage unit 131 shown in FIG. 5 stores the voltage value and the current value, it may be stored in association with the identification information that can identify the storage battery. By doing so, it becomes possible to identify the storage battery having a voltage value whose resistance value is increasing. Further, as long as the time range in which the storage unit 131 stores the voltage value and the current value includes the range corresponding to the threshold value, the width of the range is not limited. Further, the range may be divided into a plurality of ranges.

また、上述した閾値Ｖｔｈは、最大セル電圧値の値を用いているが、他の蓄電池の電圧値や最小セル電圧値またはその両方に閾値を設けても良い。また、上述した処理では、カウンタに「１」を設定することで、現在の状況が、電圧値が電圧閾値以上であり、電流値が電流閾値以上であることを識別できるようにしているが、フラグを設け、フラグを立てることで現在の状況を識別できるようにしても良く、この方法については限定しない。 Further, although the above-mentioned threshold value Vth uses the value of the maximum cell voltage value, a threshold value may be provided for the voltage value of another storage battery, the minimum cell voltage value, or both. Further, in the above-described processing, by setting "1" to the counter, it is possible to identify that the voltage value is equal to or higher than the voltage threshold value and the current value is equal to or higher than the current threshold value. A flag may be set so that the current situation can be identified by setting the flag, and this method is not limited.

このように、充電末期の蓄電池の電圧値および電流値に基づいて抵抗値を算出し、その抵抗値が増加しているかどうかを判定する。そのため、充電中に短い期間に測定した測定値を用いて抵抗値の増加を検出することができる。
（第３の実施の形態） In this way, the resistance value is calculated based on the voltage value and the current value of the storage battery at the end of charging, and it is determined whether or not the resistance value is increasing. Therefore, the increase in resistance value can be detected by using the measured value measured in a short period during charging.
(Third Embodiment)

図１０は、本発明の検出装置を用いた蓄電システムの第３の実施の形態を示す図である。
本形態は図１０に示すように、検出装置１０２と、複数の蓄電池２０２−１〜２０２−３とを有している。なお、図１０には、蓄電池２０２−１〜２０２−３が３つである場合を例に挙げて示しているが、この数に限らない。 FIG. 10 is a diagram showing a third embodiment of a power storage system using the detection device of the present invention.
As shown in FIG. 10, this embodiment has a detection device 102 and a plurality of storage batteries 202-1 to 202-3. Note that FIG. 10 shows an example in which there are three storage batteries 202-1 to 202-3, but the number is not limited to this.

蓄電池２０２−１〜２０２−３は、充電および放電可能な二次電池である。検出装置１０２は、蓄電池２０２−１〜２０２−３の電圧値および蓄電池２０２−１〜２０２−３に流れる電流値を測定する。なお、蓄電池２０２−１〜２０２−３それぞれの内部に、自身の電圧値および電流値を測定する機構が設けられている場合、検出装置１０２は、それらの測定値を取得する。 The storage batteries 202-1 to 202-3 are secondary batteries that can be charged and discharged. The detection device 102 measures the voltage value of the storage batteries 202-1 to 202-3 and the current value flowing through the storage batteries 202-1 to 202-3. If a mechanism for measuring its own voltage value and current value is provided inside each of the storage batteries 202-1 to 202-3, the detection device 102 acquires those measured values.

図１１は、図１０に示した検出装置１０２の内部構成の一例を示す図である。図１０に示した検出装置１０２は図１１に示すように、監視部１１２と、判定部１２２と、記憶部１３２とを有している。なお、図１１には、図１０に示した検出装置１０２が具備する構成要素のうち、本実施の形態に関わる主要な構成要素の一例を示す。 FIG. 11 is a diagram showing an example of the internal configuration of the detection device 102 shown in FIG. As shown in FIG. 11, the detection device 102 shown in FIG. 10 has a monitoring unit 112, a determination unit 122, and a storage unit 132. Note that FIG. 11 shows an example of the main components related to the present embodiment among the components included in the detection device 102 shown in FIG.

監視部１１２は、蓄電池２０２−１〜２０２−３に定電流定電圧充電を行う際、蓄電池２０２−１〜２０２−３の電圧値それぞれを所定の時間間隔で測定または取得する。また、監視部１１２は、蓄電池２０２−１〜２０２−３に定電流定電圧充電を行う際、蓄電池２０２−１〜２０２−３に流れる電流値を、電圧値の測定または取得のタイミングと同じタイミングで測定または取得する。このとき、監視部１１２は、蓄電池２０２−１〜２０２−３から構成される蓄電システム全体における電流値を、電圧値の測定または取得のタイミングと同じタイミングで測定または取得するものであっても良い。
記憶部１３２は、監視部１１２が測定または取得した電圧値および電流値と、判定部１２２が算出した抵抗値とを対応付けて記憶する。
判定部１２２は、蓄電池２０２−１〜２０２−３のうち、監視部１１１が測定または取得した電流値と、電圧値のうち最大である最大蓄電池の電圧値（最大セル電圧値）と、最小である最小蓄電池の電圧値（最小セル電圧値）とに基づいて、最大蓄電池の抵抗値を算出する。抵抗値の算出式としては、（式１）を用いる。判定部１２２は、電流値と最大セル電圧値と最小セル電圧値と算出した抵抗値とを対応付けて記憶部１３２に記憶させる。判定部１２２は、監視部１１２が測定した、最大セル電圧値があらかじめ設定された電圧閾値以上の値であって、電流値があらかじめ設定された電流閾値以上の値になるまで、ステップＳ２２〜Ｓ２６の処理を所定の時間間隔で行う。
判定部１２２は、特定した期間において、１つまたは複数のポイント（時刻）で（式１）を用いて抵抗値を算出する。ここで、判定部１２２が複数の抵抗値の平均値を求める場合、算出する抵抗値の数が多いほど、精密な判定が可能となることは言うまでもない。また、判定部１２２は、複数の抵抗値の平均値を求める場合、複数の時刻における抵抗値それぞれに重みづけを付与して、平均値を算出するものであっても良い。この場合、判定部１２２は、複数の時刻において、最大セル電圧値が大きいほど、高い重みづけを付与するものであっても良い。
判定部１２２は、算出した抵抗値の平均値が、セルが劣化したときの抵抗値（抵抗閾値）よりも大きな値である場合、抵抗値が増加したと判定する。このセルが劣化したときの抵抗値は、過去の運用履歴や実験等で得られた値であって、あらかじめ設定されている閾値である。例えば、判定部１２２は、電流が８Ａ以上、最大セル電圧値が４Ｖ以上の条件を満たすデータ点での抵抗相当値の平均値を算出し、算出した値が５ｍΩ以上になった場合、抵抗値増加を検知する。このとき、抵抗値増加が生じている蓄電システムの１７台中１７台を検知することができる。また、判定部１２２が抵抗値を複数の範囲で求めることで、抵抗値の継時的変化を把握することができる。 When the storage batteries 202-1 to 202-3 are charged with a constant current and a constant voltage, the monitoring unit 112 measures or acquires the voltage values of the storage batteries 202-1 to 202-3 at predetermined time intervals. Further, when the monitoring unit 112 charges the storage batteries 202-1 to 202-3 with a constant current and constant voltage, the monitoring unit 112 sets the current value flowing through the storage batteries 202-1 to 202-3 at the same timing as the timing of measuring or acquiring the voltage value. To measure or obtain at. At this time, the monitoring unit 112 may measure or acquire the current value in the entire power storage system composed of the storage batteries 202-1 to 202-3 at the same timing as the timing of measuring or acquiring the voltage value. ..
The storage unit 132 stores the voltage value and the current value measured or acquired by the monitoring unit 112 in association with the resistance value calculated by the determination unit 122.
The determination unit 122 has the current value measured or acquired by the monitoring unit 111 among the storage batteries 202-1 to 202-3, the maximum voltage value of the storage battery (maximum cell voltage value) among the voltage values, and the minimum. The resistance value of the maximum storage battery is calculated based on the voltage value (minimum cell voltage value) of a certain minimum storage battery. (Equation 1) is used as the formula for calculating the resistance value. The determination unit 122 stores the current value, the maximum cell voltage value, the minimum cell voltage value, and the calculated resistance value in association with each other in the storage unit 132. The determination unit 122 has steps S22 to S26 until the maximum cell voltage value measured by the monitoring unit 112 is equal to or higher than the preset voltage threshold value and the current value is equal to or higher than the preset current threshold value. Is performed at predetermined time intervals.
The determination unit 122 calculates the resistance value using (Equation 1) at one or a plurality of points (time) in the specified period. Here, when the determination unit 122 obtains the average value of a plurality of resistance values, it goes without saying that the larger the number of resistance values to be calculated, the more precise the determination becomes possible. Further, when the determination unit 122 obtains the average value of a plurality of resistance values, the determination unit 122 may calculate the average value by giving a weight to each of the resistance values at a plurality of times. In this case, the determination unit 122 may give a higher weight as the maximum cell voltage value is larger at a plurality of times.
When the average value of the calculated resistance values is larger than the resistance value (resistance threshold value) when the cell is deteriorated, the determination unit 122 determines that the resistance value has increased. The resistance value when this cell deteriorates is a value obtained in a past operation history, an experiment, or the like, and is a preset threshold value. For example, the determination unit 122 calculates the average value of the resistance equivalent values at the data points satisfying the conditions of the current of 8 A or more and the maximum cell voltage value of 4 V or more, and when the calculated value becomes 5 mΩ or more, the resistance value. Detect an increase. At this time, 17 out of 17 power storage systems in which the resistance value is increased can be detected. Further, the determination unit 122 obtains the resistance value in a plurality of ranges, so that the change over time of the resistance value can be grasped.

以下に、図１０に示した蓄電システムにおける抵抗値増加の検出方法について説明する。図１２は、図１０に示した蓄電システムにおける抵抗値増加の検出方法の一例を説明するためのフローチャートである。 The method of detecting the increase in the resistance value in the power storage system shown in FIG. 10 will be described below. FIG. 12 is a flowchart for explaining an example of a method for detecting an increase in resistance value in the power storage system shown in FIG.

まず、検出装置１０２は、検出装置１０２が具備しているカウンタの値をリセットして「０」とする。続いて、蓄電池２０２−１〜２０２−３に対して定電流定電圧充電を開始する（ステップＳ２１）。すると、監視部１１２は、蓄電池２０２−１〜２０２−３の電圧値それぞれを、また蓄電池２０２−１〜２０２−３に流れる電流値を所定の時間間隔で測定する（ステップＳ２２）。
続いて、判定部１２２は、監視部１１２が測定した、最大セル電圧値があらかじめ設定された電圧閾値以上の値であって、電流値があらかじめ設定された電流閾値以上の値であるかどうかを判定する（ステップＳ２３）。最大セル電圧値があらかじめ設定された電圧閾値以上の値であって、電流値があらかじめ設定された電流閾値以上の値である場合、判定部１２２は、検出装置１０２が具備しているカウンタの値を「１」とする（ステップＳ２４）。すると、判定部１２２は、そのときの最大セル電圧値と、最小セル電圧値と、電流値とに基づいて、抵抗値を算出する（ステップＳ２５）。また、判定部１２２は、最大セル電圧値と、最小セル電圧値と、電流値と、算出した抵抗値とを対応付けて記憶部１３１に記憶させる（ステップＳ２６）。その後、さらに、監視部１１２は、ステップＳ２２の処理を行う。
一方、ステップＳ２３にて、最大セル電圧値があらかじめ設定された電圧閾値以上の値ではない、または電流値があらかじめ設定された電流閾値以上の値ではない場合、判定部１２２は、カウンタの値が「１」であるかどうかを判定する（ステップＳ２７）。カウンタの値が「１」ではない場合、さらに、監視部１１２は、ステップＳ２２の処理を行う。
ステップＳ２７にて、カウンタの値が「１」である場合、判定部１２２は、記憶部１３２が記憶している複数の抵抗値の平均値を算出する（ステップＳ２８）。このとき、判定部１２２は、複数の抵抗値それぞれに重みづけを付与して、平均値を算出するものであっても良い。この場合、判定部１２２は、複数の抵抗値において、その抵抗値と対応付けられて記憶されている最大セル電圧値が大きいほど、高い重みづけを付与するものであっても良い。すると、判定部１２２は、算出した平均値と、あらかじめ設定されている抵抗閾値とに基づいて、抵抗値が増加しているかどうかを判定する（ステップＳ２９）。具体的には、判定部１２２は、算出した平均値が、セルが劣化したときの抵抗値（抵抗閾値）よりも大きな値である場合、抵抗値が増加したと判定する。
なお、抵抗値を算出するタイミングは、ステップＳ２４の後ではなく、ステップＳ２７の後であっても良い。つまり、ステップＳ２６では、記憶部１３２が最大セル電圧値と最小セル電圧値と電流値とを対応付けて記憶しておき、ステップＳ２７の後に、判定部１２２がそれぞれの抵抗値を算出して平均値を求めるものであっても良い。 First, the detection device 102 resets the value of the counter included in the detection device 102 to "0". Subsequently, constant current and constant voltage charging is started for the storage batteries 202-1 to 202-3 (step S21). Then, the monitoring unit 112 measures each of the voltage values of the storage batteries 202-1 to 202-3 and the current value flowing through the storage batteries 202-1 to 202-3 at predetermined time intervals (step S22).
Subsequently, the determination unit 122 determines whether or not the maximum cell voltage value measured by the monitoring unit 112 is a value equal to or higher than the preset voltage threshold value and the current value is equal to or higher than the preset current threshold value. Determine (step S23). When the maximum cell voltage value is equal to or higher than the preset voltage threshold value and the current value is equal to or higher than the preset current threshold value, the determination unit 122 determines the value of the counter provided in the detection device 102. Is set to "1" (step S24). Then, the determination unit 122 calculates the resistance value based on the maximum cell voltage value, the minimum cell voltage value, and the current value at that time (step S25). Further, the determination unit 122 stores the maximum cell voltage value, the minimum cell voltage value, the current value, and the calculated resistance value in the storage unit 131 in association with each other (step S26). After that, the monitoring unit 112 further performs the process of step S22.
On the other hand, in step S23, when the maximum cell voltage value is not equal to or higher than the preset voltage threshold value or the current value is not equal to or higher than the preset current threshold value, the determination unit 122 determines that the counter value is set. It is determined whether or not it is "1" (step S27). If the value of the counter is not "1", the monitoring unit 112 further performs the process of step S22.
When the value of the counter is "1" in step S27, the determination unit 122 calculates the average value of the plurality of resistance values stored in the storage unit 132 (step S28). At this time, the determination unit 122 may give a weight to each of the plurality of resistance values and calculate the average value. In this case, the determination unit 122 may give a higher weight to the plurality of resistance values as the maximum cell voltage value stored in association with the resistance values is larger. Then, the determination unit 122 determines whether or not the resistance value is increasing based on the calculated average value and the preset resistance threshold value (step S29). Specifically, the determination unit 122 determines that the resistance value has increased when the calculated average value is larger than the resistance value (resistance threshold value) when the cell deteriorates.
The timing for calculating the resistance value may be after step S27 instead of after step S24. That is, in step S26, the storage unit 132 stores the maximum cell voltage value, the minimum cell voltage value, and the current value in association with each other, and after step S27, the determination unit 122 calculates and averages the respective resistance values. The value may be calculated.

このように、充電末期の蓄電池の電圧値および電流値に基づいて、複数の抵抗値を算出し、その抵抗値の平均値を算出し、算出した平均値が増加しているかどうかを判定する。そのため、充電中に短い期間に測定した測定値を用いて抵抗値の増加を精密に検出することができる。 In this way, a plurality of resistance values are calculated based on the voltage value and the current value of the storage battery at the end of charging, the average value of the resistance values is calculated, and it is determined whether or not the calculated average value is increasing. Therefore, the increase in resistance value can be accurately detected by using the measured value measured in a short period during charging.

上述した第２および第３の実施の形態においては、判定部１２２が抵抗値を算出し、算出した抵抗値と抵抗閾値とを比較し、その比較結果に基づいて、抵抗値増加を検出する例を示した。第２および第３の実施の形態においても、第１の実施の形態において説明したような形態を用いて、判定部１２２が所定の蓄電池の電圧値と最小セル電圧値との電圧差を算出し、算出した電圧差と電圧差閾値とを比較し、その比較結果に基づいて抵抗値増加を検出しても良い。このとき、判定部１２２は、所定の蓄電池の電圧値と最小セル電圧値との電圧差が電圧差閾値以上である場合、抵抗値が増加していると判定する。また、電圧差についても、上述したように複数の電圧差の平均値を算出するものや、複数の電圧差それぞれに重みづけを付与して、平均値を算出するものであっても良い。この場合、判定部１２２は、複数の時刻において、最大セル電圧値が大きいほど、高い重みづけを付与するものであっても良い。 In the second and third embodiments described above, the determination unit 122 calculates the resistance value, compares the calculated resistance value with the resistance threshold value, and detects an increase in the resistance value based on the comparison result. showed that. Also in the second and third embodiments, the determination unit 122 calculates the voltage difference between the voltage value of the predetermined storage battery and the minimum cell voltage value by using the embodiment as described in the first embodiment. , The calculated voltage difference may be compared with the voltage difference threshold value, and the increase in resistance value may be detected based on the comparison result. At this time, the determination unit 122 determines that the resistance value is increasing when the voltage difference between the voltage value of the predetermined storage battery and the minimum cell voltage value is equal to or greater than the voltage difference threshold value. Further, as for the voltage difference, the average value of a plurality of voltage differences may be calculated as described above, or the average value may be calculated by giving a weight to each of the plurality of voltage differences. In this case, the determination unit 122 may give a higher weight as the maximum cell voltage value is larger at a plurality of times.

なお、上述した形態を単独で用いるものであっても良いし、組み合わせて用いるものであっても良い。また、抵抗値増加を原因として電圧降下が生じることを利用するものであれば、他の方法を用いるものであっても良い。また、蓄電池の種類や材質については、特に規定しない。 In addition, the above-mentioned forms may be used alone or in combination. Further, as long as it utilizes the fact that a voltage drop occurs due to an increase in resistance value, another method may be used. In addition, the type and material of the storage battery are not specified.

上述した検出装置１００〜１０２それぞれに設けられた各構成要素は、ハードウェア単位の要素ではなく、機能単位の要素を示している。また、検出装置１００〜１０２それぞれが行う処理は、目的に応じてそれぞれ作製された論理回路で行うようにしても良い。また、処理内容を手順として記述したコンピュータプログラム（以下、プログラムと称する）を検出装置１００〜１０２それぞれにて読取可能な記録媒体に記録し、この記録媒体に記録されたプログラムを検出装置１００〜１０２それぞれに読み込ませ、実行するものであっても良い。検出装置１００〜１０２それぞれにて読取可能な記録媒体とは、フロッピー（登録商標）ディスク、光磁気ディスク、ＤＶＤ（ＤｉｇｉｔａｌＶｅｒｓａｔｉｌｅＤｉｓｃ）、ＣＤ（ＣｏｍｐａｃｔＤｉｓｃ）、Ｂｌｕ−ｒａｙ（登録商標）Ｄｉｓｃなどの移設可能な記録媒体の他、検出装置１００〜１０２それぞれに内蔵されたＲＯＭ（ＲｅａｄＯｎｌｙＭｅｍｏｒｙ）、ＲＡＭ（ＲａｎｄｏｍＡｃｃｅｓｓＭｅｍｏｒｙ）等のメモリやＨＤＤ（ＨａｒｄＤｉｓｃＤｒｉｖｅ）等を指す。この記録媒体に記録されたプログラムは、検出装置１００〜１０２それぞれに設けられたＣＰＵ（ＣｅｎｔｒａｌＰｒｏｃｅｓｓｉｎｇＵｎｉｔ）にて読み込まれ、ＣＰＵの制御によって、上述したものと同様の処理が行われる。ここで、ＣＰＵは、プログラムが記録された記録媒体から読み込まれたプログラムを実行するコンピュータとして動作するものである。 Each component provided in each of the detection devices 100 to 102 described above indicates an element of a functional unit, not an element of a hardware unit. Further, the processing performed by each of the detection devices 100 to 102 may be performed by logic circuits manufactured according to the purpose. Further, a computer program (hereinafter referred to as a program) in which the processing contents are described as a procedure is recorded on a recording medium that can be read by each of the detection devices 100 to 102, and the program recorded on the recording medium is recorded on the detection devices 100 to 102. It may be read by each and executed. Recording media that can be read by each of the detection devices 100 to 102 include a floppy (registered trademark) disk, a magneto-optical disk, a DVD (Digital Versaille Disc), a CD (Compact Disc), and a Blu-ray (registered trademark) Disc. In addition to the transferable recording medium, it refers to a memory such as a ROM (Read Only Memory) and a RAM (Random Access Memory) built in each of the detection devices 100 to 102, an HDD (Hard Disk Drive), and the like. The program recorded on the recording medium is read by a CPU (Central Processing Unit) provided in each of the detection devices 100 to 102, and the same processing as described above is performed under the control of the CPU. Here, the CPU operates as a computer that executes a program read from a recording medium in which the program is recorded.

以上、実施形態を参照して本願発明を説明したが、本願発明は、上記実施形態に限定されたものではない。本願発明の構成や詳細には、本願発明のスコープ内で当業者が理解し得る様々な変更を行うことができる。 Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the above embodiments. Various changes that can be understood by those skilled in the art can be made within the scope of the present invention in terms of the structure and details of the present invention.

上記の実施の形態の一部または全部は、以下の付記のようにも記載され得るが、以下には限られない。
（付記１）複数の蓄電池に定電流定電圧充電を行う際、前記複数の蓄電池の電圧値および該複数の蓄電池へ流れる電流値それぞれを所定の時間間隔で測定する監視部と、
前記複数の蓄電池のうち、前記監視部が測定した所定の蓄電池の電圧値が所定の電圧閾値以上であり、かつそのときに前記監視部が測定した電流値が所定の電流閾値以上である場合、該電圧値と前記複数の蓄電池の電圧値のうち最小となる最小セル電圧値とに基づいて、前記蓄電池の抵抗値が増加しているか否かを判定する判定部とを有する検出装置。
（付記２）前記判定部は、前記監視部が測定した所定の蓄電池の電圧値が所定の電圧閾値以上であり、かつそのときに前記監視部が測定した電流値が所定の電流閾値以上である場合の該電圧値と該電流値と前記最小セル電圧値とに基づいて抵抗値を算出し、該算出した抵抗値と所定の抵抗閾値とに基づいて、前記抵抗値が増加しているか否かを判定する、付記１に記載の検出装置。
（付記３）前記判定部は、前記所定の蓄電池の電圧値が所定の電圧閾値以上である場合の該電圧値から前記最小セル電圧値を差し引いた値を、前記監視部が測定した電流値で除算した値を前記抵抗値として算出する、付記２に記載の検出装置。
（付記４）前記判定部は、前記所定の蓄電池の電圧値が前記電圧閾値以上であり、かつ前記電流値が前記電流閾値以上である期間において、複数の測定時刻における前記抵抗値の平均値を算出し、該算出した抵抗値の平均値と前記抵抗閾値とに基づいて、前記抵抗値が増加しているか否かを判定する、付記３に記載の検出装置。
（付記５）前記判定部は、前記複数の測定時刻において、前記監視部が測定した電圧値が大きいほど、高い重みづけを付与して前記平均値を算出する、付記４に記載の検出装置。
（付記６）前記判定部は、前記算出した抵抗値が前記抵抗閾値よりも大きな値である場合、前記抵抗値が増加していると判定する、付記２から５のいずれか１項に記載の検出装置。
（付記７）前記所定の蓄電池は、前記複数の蓄電池のうち、前記監視部が測定した電圧値が最大である蓄電池である、付記１から６のいずれか１項に記載の検出装置。
（付記８）前記判定部は、前記監視部が測定した所定の蓄電池の電圧値が所定の電圧閾値以上であり、かつそのときに前記監視部が測定した電流値が所定の電流閾値以上である場合の該電圧値と前記最小セル電圧値との電圧差と、電圧差閾値とを比較し、該比較結果に基づいて、前記抵抗値が増加しているか否かを判定する検出装置。
（付記９）前記判定部は、前記所定の蓄電池の電圧値が前記電圧閾値以上であり、かつ前記電流値が前記電流閾値以上である期間において、複数の測定時刻における前記電圧差の平均値を算出し、該算出した電圧差の平均値と前記電圧差閾値とに基づいて、前記抵抗値が増加しているか否かを判定する、付記８に記載の検出装置。
（付記１０）前記判定部は、前記複数の測定時刻において、前記監視部が測定した電圧値が大きいほど、高い重みづけを付与して前記平均値を算出する、付記９に記載の検出装置。
（付記１１）複数の蓄電池に定電流定電圧充電を行う際、前記複数の蓄電池の電圧値および該複数の蓄電池へ流れる電流値それぞれを所定の時間間隔で測定する処理と、
前記複数の蓄電池のうち、前記測定した所定の蓄電池の電圧値が所定の電圧閾値以上であるか否かを判定する処理と、
前記所定の蓄電池の電圧値が所定の電圧閾値以上である場合に測定した電流値が所定の電流閾値以上であるか否かを判定する処理と、
前記複数の蓄電池のうち、前記所定の蓄電池の電圧値が前記電圧閾値以上であり、かつそのときに測定した電流値が前記電流閾値以上である場合、該電圧値と前記複数の蓄電池の電圧値のうち最小となる最小セル電圧値とに基づいて、前記蓄電池の抵抗値が増加しているか否かを判定する処理とを行う検出方法。
（付記１２）複数の蓄電池と、
前記複数の蓄電池の抵抗値を検出する検出装置とを有し、
前記検出装置は、
前記複数の蓄電池に定電流定電圧充電を行う際、前記複数の蓄電池の電圧値および該複数の蓄電池へ流れる電流値それぞれを所定の時間間隔で測定する監視部と、
前記複数の蓄電池のうち、前記監視部が測定した所定の蓄電池の電圧値が所定の電圧閾値以上であり、かつそのときに前記監視部が測定した電流値が所定の電流閾値以上である場合、該電圧値と前記複数の蓄電池の電圧値のうち最小となる最小セル電圧値とに基づいて、前記蓄電池の抵抗値が増加しているか否かを判定する判定部とを有する蓄電システム。
（付記１３）コンピュータに、
複数の蓄電池に定電流定電圧充電を行う際、前記複数の蓄電池の電圧値および該複数の蓄電池へ流れる電流値それぞれを所定の時間間隔で測定する手順と、
前記複数の蓄電池のうち、前記測定した所定の蓄電池の電圧値が所定の電圧閾値以上であるか否かを判定する手順と、
前記所定の蓄電池の電圧値が所定の電圧閾値以上である場合に測定した電流値が所定の電流閾値以上であるか否かを判定する手順と、
前記複数の蓄電池のうち、前記所定の蓄電池の電圧値が前記電圧閾値以上であり、かつそのときに測定した電流値が前記電流閾値以上である場合、該電圧値と前記複数の蓄電池の電圧値のうち最小となる最小セル電圧値とに基づいて、前記蓄電池の抵抗値が増加しているか否かを判定する手順とを実行させるためのプログラム。 Some or all of the above embodiments may also be described, but not limited to:
(Appendix 1) When a plurality of storage batteries are charged with a constant current and a constant voltage, a monitoring unit that measures the voltage values of the plurality of storage batteries and the current values flowing through the plurality of storage batteries at predetermined time intervals.
When the voltage value of the predetermined storage battery measured by the monitoring unit is equal to or higher than the predetermined voltage threshold value among the plurality of storage batteries, and the current value measured by the monitoring unit at that time is equal to or higher than the predetermined current threshold value. A detection device having a determination unit for determining whether or not the resistance value of the storage battery is increasing based on the voltage value and the minimum cell voltage value that is the minimum among the voltage values of the plurality of storage batteries.
(Appendix 2) In the determination unit, the voltage value of the predetermined storage battery measured by the monitoring unit is equal to or higher than the predetermined voltage threshold, and the current value measured by the monitoring unit at that time is equal to or higher than the predetermined current threshold. A resistance value is calculated based on the voltage value, the current value, and the minimum cell voltage value in the case, and whether or not the resistance value is increased based on the calculated resistance value and a predetermined resistance threshold value. The detection device according to Appendix 1, which determines.
(Appendix 3) The determination unit uses the current value measured by the monitoring unit as a value obtained by subtracting the minimum cell voltage value from the voltage value when the voltage value of the predetermined storage battery is equal to or higher than the predetermined voltage threshold value. The detection device according to Appendix 2, wherein the divided value is calculated as the resistance value.
(Appendix 4) The determination unit determines the average value of the resistance values at a plurality of measurement times during a period in which the voltage value of the predetermined storage battery is equal to or higher than the voltage threshold value and the current value is equal to or higher than the current threshold value. The detection device according to Appendix 3, which is calculated and determines whether or not the resistance value is increasing based on the average value of the calculated resistance values and the resistance threshold value.
(Appendix 5) The detection device according to Appendix 4, wherein the determination unit calculates the average value by giving a higher weight as the voltage value measured by the monitoring unit increases at the plurality of measurement times.
(Supplementary note 6) The item according to any one of Supplementary note 2 to 5, wherein the determination unit determines that the resistance value is increasing when the calculated resistance value is larger than the resistance threshold value. Detection device.
(Supplementary note 7) The detection device according to any one of Supplementary note 1 to 6, wherein the predetermined storage battery is a storage battery having the maximum voltage value measured by the monitoring unit among the plurality of storage batteries.
(Appendix 8) In the determination unit, the voltage value of the predetermined storage battery measured by the monitoring unit is equal to or higher than the predetermined voltage threshold value, and the current value measured by the monitoring unit at that time is equal to or higher than the predetermined current threshold value. A detection device that compares the voltage difference between the voltage value and the minimum cell voltage value in the case and the voltage difference threshold value, and determines whether or not the resistance value is increased based on the comparison result.
(Appendix 9) The determination unit calculates the average value of the voltage differences at a plurality of measurement times during a period in which the voltage value of the predetermined storage battery is equal to or higher than the voltage threshold value and the current value is equal to or higher than the current threshold value. The detection device according to Appendix 8, which is calculated and determines whether or not the resistance value is increased based on the calculated average value of the voltage difference and the voltage difference threshold value.
(Appendix 10) The detection device according to Appendix 9, wherein the determination unit calculates the average value by giving a higher weight as the voltage value measured by the monitoring unit increases at the plurality of measurement times.
(Appendix 11) When a plurality of storage batteries are charged with a constant current and a constant voltage, a process of measuring the voltage values of the plurality of storage batteries and the current values flowing through the plurality of storage batteries at predetermined time intervals, and
Among the plurality of storage batteries, a process of determining whether or not the measured voltage value of the predetermined storage battery is equal to or higher than a predetermined voltage threshold value.
A process of determining whether or not the measured current value is equal to or higher than the predetermined current threshold value when the voltage value of the predetermined storage battery is equal to or higher than the predetermined voltage threshold value.
Among the plurality of storage batteries, when the voltage value of the predetermined storage battery is equal to or higher than the voltage threshold value and the current value measured at that time is equal to or higher than the current threshold value, the voltage value and the voltage values of the plurality of storage batteries are obtained. A detection method that performs a process of determining whether or not the resistance value of the storage battery is increasing based on the minimum cell voltage value that is the minimum of the two.
(Appendix 12) With multiple storage batteries
It has a detection device that detects the resistance value of the plurality of storage batteries.
The detection device
When the plurality of storage batteries are charged with constant current and constant voltage, a monitoring unit that measures the voltage value of the plurality of storage batteries and the current value flowing through the plurality of storage batteries at predetermined time intervals, and
When the voltage value of the predetermined storage battery measured by the monitoring unit is equal to or higher than the predetermined voltage threshold value among the plurality of storage batteries, and the current value measured by the monitoring unit at that time is equal to or higher than the predetermined current threshold value. A power storage system having a determination unit for determining whether or not the resistance value of the storage battery is increasing based on the voltage value and the minimum cell voltage value that is the minimum among the voltage values of the plurality of storage batteries.
(Appendix 13) To the computer
When charging a plurality of storage batteries with constant current and constant voltage, a procedure for measuring the voltage value of the plurality of storage batteries and the current value flowing through the plurality of storage batteries at predetermined time intervals, and
A procedure for determining whether or not the measured voltage value of the predetermined storage battery among the plurality of storage batteries is equal to or higher than the predetermined voltage threshold value.
A procedure for determining whether or not the measured current value is equal to or higher than the predetermined current threshold value when the voltage value of the predetermined storage battery is equal to or higher than the predetermined voltage threshold value.
Among the plurality of storage batteries, when the voltage value of the predetermined storage battery is equal to or higher than the voltage threshold value and the current value measured at that time is equal to or higher than the current threshold value, the voltage value and the voltage values of the plurality of storage batteries are obtained. A program for executing a procedure for determining whether or not the resistance value of the storage battery is increasing based on the minimum cell voltage value that is the minimum of the two.

１００〜１０２検出装置
１１０〜１１２監視部
１２０〜１２２判定部
１３１，１３２記憶部
２００−１〜２００−３，２０１−１〜２０１−３，２０２−１〜２０２−３蓄電池 100 to 102 Detection device 110 to 112 Monitoring unit 120 to 122 Judgment unit 131, 132 Storage unit 200-1 to 200-3, 201-1 to 201-3, 202-1 to 202-3 Storage battery

Claims

When a plurality of storage batteries connected in series are charged with a constant current and a constant voltage, a monitoring unit that measures the voltage value of the plurality of storage batteries and the current value flowing through the plurality of storage batteries at predetermined time intervals.
When the voltage value of the predetermined storage battery measured by the monitoring unit is equal to or higher than the predetermined voltage threshold value among the plurality of storage batteries, and the current value measured by the monitoring unit at that time is equal to or higher than the predetermined current threshold value. based on the minimum cell voltage value becomes the minimum among the voltage values of the plurality of storage batteries and the voltage value, have a a determination section for determining whether or not the resistance value of the battery is increased,
The predetermined storage battery is a detection device which is a storage battery having the maximum voltage value measured by the monitoring unit among the plurality of storage batteries .

In the detection device according to claim 1,
The determination unit is the voltage when the voltage value of the predetermined storage battery measured by the monitoring unit is equal to or higher than the predetermined voltage threshold value and the current value measured by the monitoring unit at that time is equal to or higher than the predetermined current threshold value. Detection that calculates a resistance value based on the value, the current value, and the minimum cell voltage value, and determines whether or not the resistance value is increasing based on the calculated resistance value and a predetermined resistance threshold value. apparatus.

In the detection device according to claim 2,
The determination unit divides the value obtained by subtracting the minimum cell voltage value from the voltage value when the voltage value of the predetermined storage battery is equal to or higher than the predetermined voltage threshold value by the current value measured by the monitoring unit. A detection device that calculates as the resistance value.

In the detection device according to claim 3,
The determination unit calculates the average value of the resistance values at a plurality of measurement times during a period in which the voltage value of the predetermined storage battery is equal to or higher than the voltage threshold value and the current value is equal to or higher than the current threshold value. A detection device that determines whether or not the resistance value is increasing based on the calculated average value of the resistance values and the resistance threshold value.

In the detection device according to claim 4,
The determination unit is a detection device that calculates the average value by giving a higher weight as the voltage value of the predetermined storage battery measured by the monitoring unit increases at the plurality of measurement times.

In the detection device according to claim 2 or 3 .
The determination unit is a detection device that determines that the resistance value is increasing when the calculated resistance value is larger than the resistance threshold value.

In the detection device according to claim 4 or 5.
The determination unit is a detection device that determines that the resistance value is increasing when the average value of the calculated resistance values is larger than the resistance threshold value.

When constant current and constant voltage charging is performed on a plurality of storage batteries connected in series, a process of measuring the voltage value of the plurality of storage batteries and the current value flowing through the plurality of storage batteries at predetermined time intervals, and
Among the plurality of storage batteries, a process of determining whether or not the measured voltage value of the predetermined storage battery is equal to or higher than a predetermined voltage threshold value.
A process of determining whether or not the measured current value is equal to or higher than the predetermined current threshold value when the voltage value of the predetermined storage battery is equal to or higher than the predetermined voltage threshold value.
Among the plurality of storage batteries, when the voltage value of the predetermined storage battery is equal to or higher than the voltage threshold value and the current value measured at that time is equal to or higher than the current threshold value, the voltage value and the voltage values of the plurality of storage batteries are obtained. minimum based on the minimum cell voltage value which is, have rows and processing determines whether the resistance value of the battery has increased among the
A detection method in which the predetermined storage battery is a storage battery having the maximum measured voltage value among the plurality of storage batteries .

With multiple storage batteries connected in series ,
It has a detection device that detects the resistance value of the plurality of storage batteries.
The detection device
When the plurality of storage batteries are charged with constant current and constant voltage, a monitoring unit that measures the voltage value of the plurality of storage batteries and the current value flowing through the plurality of storage batteries at predetermined time intervals, and
When the voltage value of the predetermined storage battery measured by the monitoring unit is equal to or higher than the predetermined voltage threshold value among the plurality of storage batteries, and the current value measured by the monitoring unit at that time is equal to or higher than the predetermined current threshold value. based on the minimum cell voltage value becomes the minimum among the voltage values of the plurality of storage batteries and the voltage value, have a a determination section for determining whether or not the resistance value of the battery is increased,
The predetermined storage battery is a power storage system in which the voltage value measured by the monitoring unit is the largest among the plurality of storage batteries .

On the computer
When performing constant current constant voltage charging of a plurality of storage batteries connected in series, a procedure for measuring the voltage value of the plurality of storage batteries and the current value flowing through the plurality of storage batteries at predetermined time intervals, and
A procedure for determining whether or not the measured voltage value of the predetermined storage battery among the plurality of storage batteries is equal to or higher than the predetermined voltage threshold value.
A procedure for determining whether or not the measured current value is equal to or higher than the predetermined current threshold value when the voltage value of the predetermined storage battery is equal to or higher than the predetermined voltage threshold value.
Among the plurality of storage batteries, when the voltage value of the predetermined storage battery is equal to or higher than the voltage threshold value and the current value measured at that time is equal to or higher than the current threshold value, the voltage value and the voltage values of the plurality of storage batteries are obtained. The purpose is to execute a procedure for determining whether or not the resistance value of the storage battery is increasing based on the minimum cell voltage value that is the minimum of the above .
The predetermined storage battery is a program in which the measured voltage value is the maximum among the plurality of storage batteries .