JP4126860B2

JP4126860B2 - Battery assembly

Info

Publication number: JP4126860B2
Application number: JP2000259326A
Authority: JP
Inventors: 晴義山下; 敏宏勝田
Original assignee: Toyota Motor Corp
Current assignee: Toyota Motor Corp
Priority date: 2000-08-29
Filing date: 2000-08-29
Publication date: 2008-07-30
Anticipated expiration: 2020-08-29
Also published as: JP2002078217A

Description

【０００１】
【発明の属する技術分野】
本発明は、組電池の異常検出装置および組電池装置に関し、詳しくは、少なくとも一つの単電池により構成される複数のモジュール電池を直列接続してなる組電池の異常検出装置およびこうした組電池と組電池の異常検出装置とを備える組電池装置に関する。
【０００２】
【従来の技術】
従来、この種の組電池装置としては、モジュール電池毎に充放電電圧を検出して充放電の際の過充電や過放電，故障を抑止するものが提案されている（例えば、特開平５−６４３７７号公報や特開平８−１４０２０４号公報など）。この装置では、複数の単電池により構成されるモジュール電池を複数直列接続して組電池を構成し、組電池の充放電の際に各モジュール電池毎に充放電の際の電圧を検出している。
【０００３】
【発明が解決しようとする課題】
しかしながら、こうした組電池装置では、電圧検出系に生じる異常を検出することができず、電圧検出系に異常が生じている場合に適正に充放電の管理ができない。モジュール電池毎に電圧の均等化を行なう組電池装置では、電圧検出系に異常が生じた場合でもモジュール電池の電圧の均等化を行なうから、モジュール電池を過放電したり過充電したりする場合が生じる。
【０００４】
本発明の組電池の異常検出装置は、モジュール電池の電圧検出系に生じ得る異常を検出することを目的とする。また、本発明の組電池装置は、モジュール電池の電圧検出系に異常が生じたときでも組電池をより適正に使用することを目的とする。
【０００５】
なお、出願人は、この種の組電池装置としてモジュール電池の異常を検出するものを提案している（特願平９−３３９１２３号）。この装置では、モジュール電池の電圧を検出し、検出した電圧が許容範囲内にあるか否かによりモジュール電池の異常を判定している。
【０００６】
【課題を解決するための手段およびその作用・効果】
本発明の組電池の異常検出装置および組電池装置は、上述の目的の少なくとも一部を達成するために以下の手段を採った。
【０００７】
本発明の組電池装置は、少なくとも一つの単電池により構成される複数のモジュール電池を直列接続してなる組電池を有する組電池装置であって、前記複数のモジュール電池の各々の電圧を検出するモジュール電圧検出手段と、該検出された各モジュール電池の電圧に基づいて各モジュール電池の電圧の均等化を行なう均等化手段と、前記複数のモジュール電池の各々の残容量を検出する残容量検出手段と、該検出された各モジュール電池の残容量に基づいて前記モジュール電圧検出手段の異常を判定する異常判定手段と、を備える組電池の異常検出装置と、前記異常検出装置により異常が検出されたとき、前記モジュール電池の電圧と残容量との関係に基づいて、異常なモジュール電圧検出手段により検出された電圧から異常に係るモジュール電池の残容量を推定し、推定した前記異常に係るモジュール電池の残容量を他のモジュール電池の電圧と残容量との関係に当てはめることにより、前記異常に係るモジュール電池の電圧を補正する異常時電圧補正手段と、前記均等化手段による均等化とは異なり、前記他のモジュール電池の電圧が前記補正した電圧に近づく方向に前記他のモジュール電池の残容量を調整する残容量調整手段と、を備える。
【０００８】
この本発明の組電池装置では、残容量検出手段により検出された各モジュール電池の残容量に基づいてモジュール電圧検出手段の異常を判定することができる。この異常の判定は、モジュール電池の残容量とモジュール電池の電圧との関係に基づく。また、本発明の組電池装置では、異常検出装置により異常が検出されたときには、モジュール電池の電圧と残容量との関係に基づいて、異常なモジュール電圧検出手段により検出された電圧から異常に係るモジュール電池の残容量を推定し、推定した異常に係るモジュール電池の残容量を他のモジュール電池の電圧と残容量との関係に当てはめることにより、異常に係るモジュール電池の電圧を補正する異常時電圧補正手段と、均等化手段による均等化とは異なり、前記他のモジュール電池の電圧が前記補正した電圧に近づく方向に前記他のモジュール電池の残容量を調整する残容量調整手段と、を備えているため、モジュール電池の過放電や過充電の抑止、異常に係るモジュール電池のより確からしい電圧を用いて組電池を使用すること、及び各モジュール電池の残容量のバラツキを小さくすることができる。
【０００９】
また、前記組電池装置において、前記異常判定手段は、各モジュール電池の残容量の変化率に基づいて異常を判定する手段であることが好ましい。
【００１０】
また、前記組電池装置において、前記異常判定手段は、各モジュール電池の残容量の変化率の平均値を演算する変化率平均値演算手段を備え、いずれかのモジュール電池の残容量の変化率が前記変化率平均値演算手段により演算された変化率の平均値より所定倍以上大きいとき又は小さいときに前記モジュール電池検出手段のうちの該モジュール電池の電圧検出系の異常と判定する手段であることが好ましい。
【００１１】
また、前記組電池装置において、前記異常判定手段は、各モジュール電池の残容量の変化率の平均値を演算する変化率平均値演算手段を備え、いずれかのモジュール電池の残容量の変化率が前記変化率平均値演算手段により演算された変化率の平均値を含む所定範囲外のときに前記モジュール電池検出手段のうちの該モジュール電池の電圧検出系の異常と判定する手段であることが好ましい。
【００１５】
【発明の実施の形態】
次に、本発明の実施の形態を実施例を用いて説明する。図１は、本発明の一実施例である組電池の異常検出装置を備える組電池装置２０の構成の概略を示す構成図である。実施例の組電池装置２０は、図示するように、出力端子が電源ラインにより負荷１０に接続された組電池２１と、組電池２１を管理する電子制御ユニット４０とを備える。
【００１６】
組電池２１は、例えばリチウムイオン電池などの複数の単電池２２を直列接続してなる複数のモジュール電池２４ａ〜２４ｎを直列接続して構成されている。各モジュール電池２４ａ〜２４ｎには、各単電池２２の電圧を検出する電圧検出ライン２６ａ〜２６ｎを用いて各単電池２２の電圧の均等化を行なうセル均等化回路２８ａ〜２８ｎが取り付けられている。以下、ｎ個のモジュール電池２４ａ〜２４ｎに対応する各部の符号には、数字とａ〜ｎのアルファベットによる添え字とを用いて表示する。
【００１７】
電子制御ユニット４０は、ＣＰＵ４２を中心とするマイクロプロセッサとして構成されており、処理プログラムを記憶したＲＯＭ４４と、一時的にデータを記憶するＲＡＭ４６とを備える。この電子制御ユニット４０には、各モジュール電池２４ａ〜２４ｎの接続端に接続された導電ライン３２ａ〜３２ｎ＋１が接続されており、導電ライン３２ａ〜３２ｎ＋１のライン間の電位差を検出することにより各モジュール電池２４ａ〜２４ｎの電圧を検出できるようになっている。電子制御ユニット４０では、この検出した各モジュール電池２４ａ〜２４ｎの電圧に基づいて各モジュール電池２４ａ〜２４ｎの残容量Ｓａ〜Ｓｎを演算している。電圧に基づく残容量（ＳＯＣ）の演算は周知なのでその説明は省略する。また、各導電ライン３２ａ〜３２ｎ＋１の間には、抵抗３４ａ〜３４ｎとトランジスタ３６ａ〜３６ｎとが直列に接続されており、各トランジスタ３６ａ〜３６ｎのベースは信号ライン３８ａ〜３８ｎにより電子制御ユニット４０に接続されている。したがって、電子制御ユニット４０は、信号ライン３８ａ〜３８ｎにオンオフ信号を出力することによりトランジスタ３６ａ〜３６ｎをオンオフすることができる。また、電子制御ユニット４０からは、組電池２１やモジュール電池２４ａ〜２４ｎの電圧検出系の異常の際に点灯するインジケータ４８への点灯信号も出力されている。
【００１８】
次に、こうして構成された実施例の組電池装置２０の動作、特にモジュール電池２４ａ〜２４ｎの電圧検出系の異常を検出する動作とこの異常を検出したときの動作について説明する。図２は、実施例の組電池装置２０の電子制御ユニット４０により実行される異常検出処理ルーチンの一例を示すフローチャートである。このルーチンは所定時間毎（例えば、１時間毎など）に繰り返し実行される。
【００１９】
異常検出処理ルーチンが実行されると、電子制御ユニット４０のＣＰＵ４２は、まず、各導電ライン３２ａ〜３２ｎ＋１の間の電位差を検出して各モジュール電池２４ａ〜２４ｎの電圧Ｖａ〜Ｖｎを検出する処理を実行する（ステップＳ１００）。続いて、検出した各モジュール電池２４ａ〜２４ｎの電圧Ｖａ〜Ｖｎに基づいて各モジュール電池２４ａ〜２４ｎの残容量Ｓａ〜Ｓｎを演算すると共に（ステップＳ１０２）、演算した残容量Ｓａ〜Ｓｎと前回このルーチンが実行されたときに演算された残容量Ｓａ〜Ｓｎとを用いて残容量の時間変化率ＤＳａ〜ＤＳｎを計算する（ステップＳ１０４）。具体的には、今回の残容量Ｓａ〜Ｓｎと前回の残容量Ｓａ〜Ｓｎの偏差を異常検出処理ルーチンが実行される時間間隔で除することにより行なわれる。
【００２０】
そして、残容量の時間変化率ＤＳａ〜ＤＳｎの平均値Ａを計算し（ステップＳ１０６）、計算した平均値Ａに所定係数ａを乗じたものや平均値Ａに所定係数ｂを乗じたものと各残容量の時間変化率ＤＳａ〜ＤＳｎとを比較する（ステップＳ１０８）。ここで、所定係数ａおよび所定係数ｂは、残容量の時間変化率ＤＳａ〜ＤＳｎの平均値Ａからの許容されるバラツキの上限および下限を定める係数であり、単電池２２やモジュール電池２４ａ〜２４ｎの特性や仕様などにより定められる。いずれの残容量の時間変化率ＤＳａ〜ＤＳｎも平均値Ａに所定係数ａを乗じたものより小さく平均値Ａに所定係数ｂを乗じたものより大きいときには、すべての電圧検出系に異常は生じていないと判断して、本ルーチンを終了する。一方、いずれかの残容量の時間変化率ＤＳが平均値Ａに所定係数ａを乗じたものより大きいときや平均値Ａに所定係数ｂを乗じたものより小さいときには、その残容量の時間変化率ＤＳに係るモジュール電池２４の電圧検出系に異常が生じていると判定すると共にインジケータ４８を点灯して（ステップＳ１１０）、本ルーチンを終了する。ここで、残容量の時間変化率ＤＳに基づいて電圧検出系の異常が判定できるのは次の理由による。
【００２１】
図３は、正常な電圧検出系によるモジュール電池の残容量と電圧との関係と異常な電圧検出系によるモジュール電池の残容量と電圧との関係の一例を示す説明図である。図３中の異常な電圧検出系は、電圧を高めに検出するものである。後述する図４の均等化処理ルーチンのステップＳ２０４の処理としての均等化処理では、各モジュール電池２４ａ〜２４ｎの残容量Ｓａ〜Ｓｎが均等になるように電圧が高いモジュール電池に対してトランジスタ３６をオンして抵抗３４により電力を消費させる。したがって、電圧が高めに検出される異常な電圧検出系により電圧が検出されるモジュール電池では必要以上に放電されるから、同じ電圧として検出されても正常な電圧検出系により電圧が検出されるモジュール電池に比して残容量（ＳＯＣ）が小さくなる。残容量（ＳＯＣ）と電圧との関係は、図示するように、残容量（ＳＯＣ）が小さな領域と大きな領域では変化率が大きい。このため、異常な電圧検出系により電圧が検出されたモジュール電池の残容量（ＳＯＣ）の小さな領域ではその残容量の時間変化率は正常な電圧検出系により電圧が検出されたモジュール電池の残容量の時間変化率に比して大きくなり、残容量（ＳＯＣ）の大きな領域ではその残容量の時間変化率は正常な電圧検出系により電圧が検出されたモジュール電池の残容量の時間変化率に比して小さくなる。
【００２２】
逆に、電圧が低めに検出される異常な電圧検出系により電圧が検出されるモジュール電池では均等化処理による放電が行なわれないから、同じ電圧として検出されても正常な電圧検出系により電圧が検出されるモジュール電池に比して残容量（ＳＯＣ）が大きくなる。このため、異常な電圧検出系により電圧が検出されたモジュール電池の残容量（ＳＯＣ）の小さな領域ではその残容量の時間変化率は正常な電圧検出系により電圧が検出されたモジュール電池の残容量の時間変化率に比して小さくなり、残容量（ＳＯＣ）の大きな領域ではその残容量の時間変化率は正常な電圧検出系により電圧が検出されたモジュール電池の残容量の時間変化率に比して大きくなる。こうした考えを用いて、実施例では、残容量の時間変化率ＤＳａ〜ＤＳｎの平均値Ａを含む許容範囲を超える時間変化率ＤＳのモジュール電池の電圧検出系の異常を判定するのである。
【００２３】
実施例の組電池装置２０では、こうした異常検出処理の他にモジュール電池２４ａ〜２４ｎを均等化する処理も行なっている。図４は、実施例の組電池装置２０の電子制御ユニット４０により実行される均等化処理ルーチンの一例を示すフローチャートである。このルーチンは、所定時間毎（例えば３０分毎など）に繰り返し実行される。
【００２４】
均等化処理ルーチンが実行されると、電子制御ユニット４０のＣＰＵ４２は、まず、各導電ライン３２ａ〜３２ｎ＋１の間の電位差を検出して各モジュール電池２４ａ〜２４ｎの電圧Ｖａ〜Ｖｎを検出する処理を実行する（ステップＳ２００）。続いて、電圧検出系の異常が判定されたか否かを調べ（ステップＳ２０２）、異常が判定されていないときには、各モジュール電池２４ａ〜２４ｎの残容量Ｓａ〜Ｓｎが均等になるように均等化処理を実行して（ステップＳ２０４）、本ルーチンを終了する。この均等化処理は、各モジュール電池２４ａ〜２４ｎの残容量Ｓａ〜Ｓｎが均等になるように電圧が高いモジュール電池に対してトランジスタ３６をオンして抵抗３４により電力を消費させることにより行なう。
【００２５】
一方、電圧検出系の異常が判定されているときには、異常が判定された電圧検出系により電圧が検出されるモジュール電池の電圧を残容量の時間変化に基づいて補正し（ステップＳ２０６）、各モジュール電池２４ａ〜２４ｎの電圧が補正した電圧に近づくように調整して（ステップＳ２０８）、本ルーチンを終了する。電圧の補正は、図３に例示するように、モジュール電池の電圧と残容量との関係から、異常な電圧検出系により検出された電圧からモジュール電池の残容量を推定できるから、推定した残容量を正常な電圧検出系により検出される電圧と残容量との関係に当てはめて電圧を推定することにより行なう。各モジュール電池２４ａ〜２４ｎの電圧を補正した電圧に近づくように行なう調整は、電圧を高めに検出する異常な電圧検出系の場合には、正常な電圧検出系により電圧が検出される各モジュール電池２４に対してトランジスタ３６をオンとして抵抗３４により電力を消費させることにより行なうが、均等化処理とは異なり、補正した電圧になるまで放電は行なわず、補正した電圧より高い電圧までで放電が終了される。一方、電圧を低めに検出する異常な電圧検出系の場合には、異常な電圧検出系により電圧が検出されるモジュール電池２４に対してトランジスタ３６をオンとして抵抗３４により電力を消費させることにより行なう。この場合も、補正した電圧が正常な電圧検出系により検出される電圧になるまで放電するのではなく、若干高い電圧までで放電を終了する。
【００２６】
以上説明した実施例の組電池装置２０によれば、モジュール電池２４ａ〜２４ｎの電圧検出系の異常を検出することができる。この結果、電圧検出系の異常に基づくモジュール電池２４の過放電や過充電を防止することができる。また、実施例の組電池装置２０によれば、電圧検出系の異常を検出したときには、異常に係るモジュール電池２４の電圧を補正すると共に他のモジュール電池２４ａ〜２４ｎの電圧が補正した電圧に近づくよう調整するから、電圧検出系の異常に基づくモジュール電池２４の過放電や過充電を更に防止することができると共にその後の使用に資することができる。
【００２７】
実施例の組電池装置２０では、残容量の時間変化率ＤＳが平均値Ａに所定係数ａを乗じたものと所定係数ｂを乗じたものとにより設定される許容範囲外となるときにその残容量の時間変化率ＤＳに係る電圧検出系を異常と判定したが、残容量の時間変化率ＤＳが平均値Ａに所定値ｃを減じたものと所定値ｄを加えたものとにより設定される許容範囲外となるときにその残容量の時間変化率ＤＳに係る電圧検出系を異常と判定するものとしてもよい。ここで、所定値ｃおよび所定値ｄは、残容量の時間変化率ＤＳａ〜ＤＳｎの平均値Ａからの許容されるバラツキの上限および下限を定める定数であり、単電池２２やモジュール電池２４ａ〜２４ｎの特性や仕様などにより定められる。
【００２８】
実施例の組電池装置２０では、電圧検出系の異常を検出したときには、異常に係るモジュール電池２４の電圧を補正し、他のモジュール電池２４の電圧の調整を行なうものとしたが、電圧検出系の異常を検出したときには単に均等化処理を行なわないだけで、異常に係るモジュール電池２４の電圧の補正や他のモジュール電池２４の電圧の調整を行なわないものとしてもよい。
【００２９】
実施例の組電池装置２０では、異常検出処理ルーチンと均等化処理ルーチンとを別々のルーチンとして電子制御ユニット４０により実行するものとしたが、均等化処理ルーチンのステップＳ２０２処理の前に異常検出処理ルーチンのステップＳ１０２〜Ｓ１１０の処理を行なうものとして均等化処理ルーチンの中で電圧検出系の異常を検出するものとしてもよい。
【００３０】
実施例の組電池装置２０では、各モジュール電池２４ａ〜２４ｎの残容量Ｓａ〜Ｓｎを各モジュール電池２４ａ〜２４ｎの電圧Ｖａ〜Ｖｎに基づいて演算により求めるものとしたが、各モジュール電池２４ａ〜２４ｎの残容量Ｓａ〜Ｓｎを直接検出するものとしてもよいし、電圧Ｖａ〜Ｖｎ以外の状態値を用いて演算したものを用いるものとしてもよい。
【００３１】
実施例の組電池装置２０では、複数の単電池２２を直列に接続してモジュール電池２４ａ〜２４ｎを構成したが、一つの単電池２２によりモジュール電池２４ａ〜２４ｎを構成するものとしてもよい。この場合、セル均等化回路２８ａ〜２８ｎは不要となる。
【００３２】
以上、本発明の実施の形態について実施例を用いて説明したが、本発明はこうした実施例に何等限定されるものではなく、本発明の要旨を逸脱しない範囲内において、種々なる形態で実施し得ることは勿論である。
【図面の簡単な説明】
【図１】本発明の一実施例である組電池の異常検出装置を備える組電池装置２０の構成の概略を示す構成図である。
【図２】実施例の組電池装置２０の電子制御ユニット４０により実行される異常検出処理ルーチンの一例を示すフローチャートである。
【図３】正常な電圧検出系によるモジュール電池の残容量と電圧との関係と異常な電圧検出系によるモジュール電池の残容量と電圧との関係の一例を示す説明図である。
【図４】実施例の組電池装置２０の電子制御ユニット４０により実行される均等化処理ルーチンの一例を示すフローチャートである。
【符号の説明】
１０負荷、２０組電池装置、２１組電池、２２単電池、２４ａ〜２４ｎモジュール電池、２６ａ〜２６ｎ電圧検出ライン、２８ａ〜２８ｎセル均等化回路、３２ａ〜３２ｎ＋１導電ライン、３４ａ〜３４ｎ抵抗、３６ａ〜３６ｎトランジスタ、３８ａ〜３８ｎ信号ライン、４０電子制御ユニット、４２ＣＰＵ、４４ＲＯＭ、４６ＲＡＭ、４８インジケータ。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an assembled battery abnormality detection device and an assembled battery device. More specifically, the present invention relates to an assembled battery abnormality detection device in which a plurality of module batteries each composed of at least one single battery are connected in series, and such an assembled battery and assembly. The present invention relates to an assembled battery device including a battery abnormality detection device.
[0002]
[Prior art]
Conventionally, as this type of assembled battery device, a device that detects a charge / discharge voltage for each module battery and suppresses overcharge, overdischarge, and failure at the time of charge / discharge has been proposed (for example, Japanese Patent Laid-Open No. Hei 5- No. 64377 and JP-A-8-140204). In this device, a plurality of module batteries composed of a plurality of single cells are connected in series to form an assembled battery, and the voltage at the time of charging / discharging is detected for each module battery at the time of charging / discharging of the assembled battery. .
[0003]
[Problems to be solved by the invention]
However, in such an assembled battery device, an abnormality occurring in the voltage detection system cannot be detected, and charge / discharge cannot be properly managed when an abnormality occurs in the voltage detection system. In an assembled battery device that performs voltage equalization for each module battery, even if an abnormality occurs in the voltage detection system, the voltage of the module battery is equalized, so the module battery may be overdischarged or overcharged. Arise.
[0004]
An object of the present invention is to detect an abnormality that can occur in a voltage detection system for a module battery. Moreover, the assembled battery apparatus of this invention aims at using an assembled battery more appropriately, even when abnormality arises in the voltage detection system of a module battery.
[0005]
In addition, the applicant has proposed what detects abnormality of a module battery as this kind of assembled battery apparatus (Japanese Patent Application No. 9-339123). In this apparatus, the voltage of the module battery is detected, and the abnormality of the module battery is determined based on whether or not the detected voltage is within an allowable range.
[0006]
[Means for solving the problems and their functions and effects]
The battery pack abnormality detection apparatus and battery pack apparatus of the present invention employ the following means in order to achieve at least a part of the above-described object.
[0007]
An assembled battery device according to the present invention is an assembled battery device having an assembled battery formed by connecting a plurality of module batteries configured by at least one single battery in series, and detects a voltage of each of the plurality of module batteries. Module voltage detection means, equalization means for equalizing the voltage of each module battery based on the detected voltage of each module battery, and remaining capacity detection means for detecting the remaining capacity of each of the plurality of module batteries An abnormality determination device for determining abnormality of the module voltage detection means based on the detected remaining capacity of each module battery, and an abnormality is detected by the abnormality detection device. when, on the basis of the relationship between the voltage and the remaining capacity of the module battery, according to the abnormality from the voltage detected by the abnormal module voltage detector module Estimating the remaining capacity of the Le battery, by fitting the remaining capacity of the module battery according to the estimated the abnormality in the relationship between the voltage and the remaining capacity of another battery module, anomaly correcting the voltage of the module battery according to the abnormality Unlike the equalization by the time voltage correction means and the equalization means, the remaining capacity adjustment means for adjusting the remaining capacity of the other module battery in a direction in which the voltage of the other module battery approaches the corrected voltage; Is provided.
[0008]
In the assembled battery device of the present invention, it is possible to determine the abnormality of the module voltage detecting means based on the remaining capacity of each module battery detected by the remaining capacity detecting means. This abnormality determination is based on the relationship between the remaining capacity of the module battery and the voltage of the module battery. Further, in the assembled battery device of the present invention, when an abnormality is detected by the abnormality detection device, the abnormality is detected from the voltage detected by the abnormal module voltage detection means based on the relationship between the voltage of the module battery and the remaining capacity. Estimate the remaining capacity of the module battery, and apply the remaining capacity of the module battery related to the estimated abnormality to the relationship between the voltage of the other module battery and the remaining capacity, thereby correcting the voltage of the module battery related to the abnormality Unlike the equalization by the correction means and the equalization means, the remaining capacity adjustment means for adjusting the remaining capacity of the other module battery in a direction in which the voltage of the other module battery approaches the corrected voltage. Therefore, it is necessary to use an assembled battery with a more probable voltage of the module battery related to abnormality, suppression of overdischarge and overcharge of the module battery, Beauty variations of the remaining capacity of each battery module can be reduced.
[0009]
In the assembled battery device, it is preferable that the abnormality determination unit is a unit that determines abnormality based on a rate of change in remaining capacity of each module battery.
[0010]
Further, in the assembled battery device, the abnormality determination means includes a change rate average value calculating means for calculating an average value of the change rate of the remaining capacity of each module battery, and the change rate of the remaining capacity of any of the module batteries is The module battery detecting means is a means for determining that the voltage detection system of the module battery is abnormal when the average value of the change rate calculated by the change rate average value calculating means is larger or smaller than a predetermined multiple. Is preferred.
[0011]
Further, in the assembled battery device, the abnormality determination means includes a change rate average value calculating means for calculating an average value of the change rate of the remaining capacity of each module battery, and the change rate of the remaining capacity of any of the module batteries is Preferably, the module battery detection means is a means for determining an abnormality in the voltage detection system of the module battery when the average value of the change rate calculated by the change rate average value calculation means is outside a predetermined range. .
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described using examples. FIG. 1 is a configuration diagram showing an outline of a configuration of an assembled battery device 20 including an assembled battery abnormality detection device according to an embodiment of the present invention. As illustrated, the assembled battery device 20 of the embodiment includes an assembled battery 21 whose output terminal is connected to the load 10 by a power line, and an electronic control unit 40 that manages the assembled battery 21.
[0016]
The assembled battery 21 is configured by connecting a plurality of module batteries 24a to 24n formed by connecting a plurality of unit cells 22 such as lithium ion batteries in series. Cell equalization circuits 28a to 28n for equalizing the voltages of the unit cells 22 using the voltage detection lines 26a to 26n for detecting the voltages of the unit cells 22 are attached to the module batteries 24a to 24n. . Hereinafter, the numerals of the parts corresponding to the n module batteries 24a to 24n are displayed using numerals and subscripts of alphabets a to n.
[0017]
The electronic control unit 40 is configured as a microprocessor centered on a CPU 42 and includes a ROM 44 that stores a processing program and a RAM 46 that temporarily stores data. The electronic control unit 40 is connected to conductive lines 32a to 32n + 1 connected to the connection ends of the module batteries 24a to 24n, and each module battery is detected by detecting a potential difference between the conductive lines 32a to 32n + 1. The voltages 24a to 24n can be detected. In the electronic control unit 40, the remaining capacities Sa to Sn of the module batteries 24a to 24n are calculated based on the detected voltages of the module batteries 24a to 24n. Since the calculation of the remaining capacity (SOC) based on the voltage is well known, its description is omitted. Further, resistors 34a to 34n and transistors 36a to 36n are connected in series between the conductive lines 32a to 32n + 1, and the bases of the transistors 36a to 36n are connected to the electronic control unit 40 by signal lines 38a to 38n. It is connected. Therefore, the electronic control unit 40 can turn on and off the transistors 36a to 36n by outputting on / off signals to the signal lines 38a to 38n. The electronic control unit 40 also outputs a lighting signal to the indicator 48 that lights when the voltage detection system of the assembled battery 21 or the module batteries 24a to 24n is abnormal.
[0018]
Next, the operation of the assembled battery device 20 of the embodiment configured as described above, particularly the operation for detecting the abnormality of the voltage detection system of the module batteries 24a to 24n and the operation when this abnormality is detected will be described. FIG. 2 is a flowchart illustrating an example of an abnormality detection processing routine executed by the electronic control unit 40 of the assembled battery device 20 according to the embodiment. This routine is repeatedly executed every predetermined time (for example, every hour).
[0019]
When the abnormality detection processing routine is executed, the CPU 42 of the electronic control unit 40 first detects a potential difference between the conductive lines 32a to 32n + 1 to detect the voltages Va to Vn of the module batteries 24a to 24n. Execute (Step S100). Subsequently, the remaining capacity Sa to Sn of each module battery 24a to 24n is calculated based on the detected voltage Va to Vn of each module battery 24a to 24n (step S102), and the calculated remaining capacity Sa to Sn and the previous time The remaining capacity time change rates DSa to DSn are calculated using the remaining capacity Sa to Sn calculated when the routine is executed (step S104). Specifically, this is performed by dividing the deviation between the current remaining capacity Sa to Sn and the previous remaining capacity Sa to Sn by the time interval at which the abnormality detection processing routine is executed.
[0020]
Then, an average value A of the remaining capacity time change rates DSa to DSn is calculated (step S106), and the calculated average value A is multiplied by a predetermined coefficient a, the average value A is multiplied by a predetermined coefficient b, and each The time change rates DSa to DSn of the remaining capacity are compared (step S108). Here, the predetermined coefficient a and the predetermined coefficient b are coefficients that determine an upper limit and a lower limit of the allowable variation from the average value A of the time change rates DSa to DSn of the remaining capacity, and the single battery 22 and the module batteries 24a to 24n. It is determined by the characteristics and specifications. When any of the remaining capacity time change rates DSa to DSn is smaller than the average value A multiplied by the predetermined coefficient a and larger than the average value A multiplied by the predetermined coefficient b, an abnormality has occurred in all voltage detection systems. If it is determined that there is no, this routine is terminated. On the other hand, when the time change rate DS of any remaining capacity is larger than the average value A multiplied by the predetermined coefficient a or smaller than the average value A multiplied by the predetermined coefficient b, the time change rate of the remaining capacity It is determined that an abnormality has occurred in the voltage detection system of the module battery 24 related to DS, and the indicator 48 is turned on (step S110), and this routine ends. Here, the abnormality of the voltage detection system can be determined based on the time change rate DS of the remaining capacity for the following reason.
[0021]
FIG. 3 is an explanatory diagram showing an example of the relationship between the remaining capacity and voltage of the module battery by the normal voltage detection system and the relationship between the remaining capacity and voltage of the module battery by the abnormal voltage detection system. The abnormal voltage detection system in FIG. 3 detects a high voltage. In the equalization process as the process of step S204 of the equalization process routine of FIG. 4 described later, the transistor 36 is connected to the module battery having a high voltage so that the remaining capacities Sa to Sn of the module batteries 24a to 24n are equalized. It is turned on and power is consumed by the resistor 34. Therefore, a module battery in which the voltage is detected by an abnormal voltage detection system that detects a high voltage is discharged more than necessary, so even if it is detected as the same voltage, the module can detect the voltage by a normal voltage detection system The remaining capacity (SOC) is smaller than that of the battery. As shown in the figure, the rate of change between the remaining capacity (SOC) and the voltage is large in a region where the remaining capacity (SOC) is small and a large region. For this reason, in the region where the remaining capacity (SOC) of the module battery in which the voltage is detected by the abnormal voltage detection system is small, the time change rate of the remaining capacity is the remaining capacity of the module battery in which the voltage is detected by the normal voltage detection system. In the region where the remaining capacity (SOC) is large, the time changing rate of the remaining capacity is compared with the time changing rate of the remaining capacity of the module battery whose voltage is detected by the normal voltage detection system. And get smaller.
[0022]
On the contrary, the module battery in which the voltage is detected by the abnormal voltage detection system in which the voltage is detected at a low voltage does not discharge by the equalization process. Therefore, even if it is detected as the same voltage, the voltage is detected by the normal voltage detection system. The remaining capacity (SOC) becomes larger than the detected module battery. For this reason, in the region where the remaining capacity (SOC) of the module battery in which the voltage is detected by the abnormal voltage detection system is small, the time change rate of the remaining capacity is the remaining capacity of the module battery in which the voltage is detected by the normal voltage detection system. In the region where the remaining capacity (SOC) is large, the time change rate of the remaining capacity is compared with the time change ratio of the remaining capacity of the module battery whose voltage is detected by the normal voltage detection system. And get bigger. Using this idea, in the embodiment, the abnormality of the voltage detection system of the module battery having the time change rate DS exceeding the allowable range including the average value A of the time change rates DSa to DSn of the remaining capacity is determined.
[0023]
In the assembled battery device 20 of the embodiment, in addition to such abnormality detection processing, processing for equalizing the module batteries 24a to 24n is also performed. FIG. 4 is a flowchart illustrating an example of an equalization processing routine executed by the electronic control unit 40 of the assembled battery device 20 according to the embodiment. This routine is repeatedly executed every predetermined time (for example, every 30 minutes).
[0024]
When the equalization processing routine is executed, the CPU 42 of the electronic control unit 40 first detects a potential difference between the conductive lines 32a to 32n + 1 to detect voltages Va to Vn of the module batteries 24a to 24n. Execute (Step S200). Subsequently, it is checked whether or not an abnormality of the voltage detection system has been determined (step S202). When the abnormality has not been determined, an equalization process is performed so that the remaining capacities Sa to Sn of the module batteries 24a to 24n are equalized. Is executed (step S204), and this routine is terminated. This equalization processing is performed by turning on the transistor 36 and consuming power by the resistor 34 with respect to the module battery having a high voltage so that the remaining capacities Sa to Sn of the module batteries 24 a to 24 n are equalized.
[0025]
On the other hand, when the abnormality of the voltage detection system is determined, the voltage of the module battery whose voltage is detected by the voltage detection system where the abnormality is determined is corrected based on the time change of the remaining capacity (step S206), and each module Adjustment is made so that the voltages of the batteries 24a to 24n approach the corrected voltage (step S208), and this routine ends. As illustrated in FIG. 3, the voltage correction can estimate the remaining capacity of the module battery from the voltage detected by the abnormal voltage detection system from the relationship between the voltage of the module battery and the remaining capacity. Is applied to the relationship between the voltage detected by the normal voltage detection system and the remaining capacity to estimate the voltage. In the case of an abnormal voltage detection system in which the voltage of each module battery 24a to 24n is approximated to the corrected voltage, in the case of an abnormal voltage detection system that detects the voltage higher, each module battery whose voltage is detected by the normal voltage detection system 24, the transistor 36 is turned on and power is consumed by the resistor 34. However, unlike the equalization process, the discharge is not performed until the corrected voltage is reached, and the discharge is terminated at a voltage higher than the corrected voltage. Is done. On the other hand, in the case of an abnormal voltage detection system that detects a voltage at a low level, the module battery 24 whose voltage is detected by the abnormal voltage detection system is turned on and the power is consumed by the resistor 34 by turning on the transistor 36. . Also in this case, the discharge is not finished until the corrected voltage becomes a voltage detected by a normal voltage detection system, but the discharge is terminated at a slightly higher voltage.
[0026]
According to the assembled battery device 20 of the embodiment described above, the abnormality of the voltage detection system of the module batteries 24a to 24n can be detected. As a result, overdischarge and overcharge of the module battery 24 based on abnormality of the voltage detection system can be prevented. Further, according to the assembled battery device 20 of the embodiment, when the abnormality of the voltage detection system is detected, the voltage of the module battery 24 related to the abnormality is corrected and the voltages of the other module batteries 24a to 24n approach the corrected voltage. Thus, the module battery 24 can be further prevented from being overdischarged or overcharged due to an abnormality in the voltage detection system, and can be used for subsequent use.
[0027]
In the assembled battery device 20 according to the embodiment, when the time change rate DS of the remaining capacity falls outside the allowable range set by the average value A multiplied by the predetermined coefficient a and the predetermined coefficient b. Although the voltage detection system related to the time change rate DS of the capacity is determined to be abnormal, the time change rate DS of the remaining capacity is set based on a value obtained by subtracting the predetermined value c from the average value A and a value obtained by adding the predetermined value d. The voltage detection system related to the time change rate DS of the remaining capacity may be determined to be abnormal when it falls outside the allowable range. Here, the predetermined value c and the predetermined value d are constants that define an upper limit and a lower limit of an allowable variation from the average value A of the time change rates DSa to DSn of the remaining capacity, and the single battery 22 and the module batteries 24a to 24n. It is determined by the characteristics and specifications.
[0028]
In the assembled battery device 20 of the embodiment, when the abnormality of the voltage detection system is detected, the voltage of the module battery 24 related to the abnormality is corrected and the voltage of the other module battery 24 is adjusted. When an abnormality is detected, the equalization process is not performed, and the voltage of the module battery 24 related to the abnormality or the voltage of another module battery 24 may not be adjusted.
[0029]
In the assembled battery device 20 of the embodiment, the abnormality detection processing routine and the equalization processing routine are executed by the electronic control unit 40 as separate routines, but the abnormality detection processing is performed before step S202 of the equalization processing routine. It is good also as what detects abnormality of a voltage detection system in an equalization processing routine as what performs processing of Steps S102-S110 of a routine.
[0030]
In the assembled battery device 20 of the embodiment, the remaining capacities Sa to Sn of the module batteries 24a to 24n are obtained by calculation based on the voltages Va to Vn of the module batteries 24a to 24n, but the module batteries 24a to 24n are calculated. The remaining capacities Sa to Sn may be directly detected, or those calculated using state values other than the voltages Va to Vn may be used.
[0031]
In the assembled battery device 20 of the embodiment, the plurality of unit cells 22 are connected in series to form the module batteries 24a to 24n. However, the single unit cell 22 may constitute the module batteries 24a to 24n. In this case, the cell equalization circuits 28a to 28n are not necessary.
[0032]
The embodiments of the present invention have been described using the embodiments. However, the present invention is not limited to these embodiments, and can be implemented in various forms without departing from the gist of the present invention. Of course you get.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing an outline of a configuration of an assembled battery device 20 including an assembled battery abnormality detection device according to an embodiment of the present invention.
FIG. 2 is a flowchart illustrating an example of an abnormality detection processing routine executed by the electronic control unit 40 of the assembled battery device 20 according to the embodiment.
FIG. 3 is an explanatory diagram showing an example of the relationship between the remaining capacity and voltage of the module battery by a normal voltage detection system and the relationship between the remaining capacity and voltage of the module battery by an abnormal voltage detection system;
FIG. 4 is a flowchart illustrating an example of an equalization processing routine executed by the electronic control unit 40 of the assembled battery device 20 according to the embodiment.
[Explanation of symbols]
10 load, 20 assembled battery device, 21 assembled battery, 22 single battery, 24a-24n module battery, 26a-26n voltage detection line, 28a-28n cell equalization circuit, 32a-32n + 1 conductive line, 34a-34n resistance, 36a- 36n transistor, 38a-38n signal line, 40 electronic control unit, 42 CPU, 44 ROM, 46 RAM, 48 indicator.

Claims

An assembled battery device having an assembled battery formed by connecting a plurality of module batteries constituted by at least one single battery in series,
Module voltage detection means for detecting the voltage of each of the plurality of module batteries, equalization means for equalizing the voltage of each module battery based on the detected voltage of each module battery, and the plurality of module batteries A battery pack abnormality detection device comprising: a remaining capacity detection means for detecting each remaining capacity of the battery module; and an abnormality determination means for determining an abnormality of the module voltage detection means based on the detected remaining capacity of each module battery. When,
When an abnormality is detected by the abnormality detection device , the remaining capacity of the module battery related to the abnormality is estimated from the voltage detected by the abnormal module voltage detection means based on the relationship between the voltage of the module battery and the remaining capacity. An abnormal voltage correction means for correcting the voltage of the module battery related to the abnormality by applying the estimated remaining capacity of the module battery related to the abnormality to the relationship between the voltage of the other module battery and the remaining capacity;
Unlike the equalization by the equalization means, an assembled battery device comprising: a remaining capacity adjustment means for adjusting a remaining capacity of the other module battery in a direction in which the voltage of the other module battery approaches the corrected voltage.

The assembled battery device according to claim 1, wherein the abnormality determination unit is a unit that determines abnormality based on a change rate of a remaining capacity of each module battery.

The abnormality determining means includes a change rate average value calculating means for calculating an average value of the change rate of the remaining capacity of each module battery, and the change rate of the remaining capacity of any module battery is calculated by the change rate average value calculating means. 3. The assembled battery device according to claim 2, which is means for determining that the module battery voltage detection system has an abnormality in the module battery detection means when the calculated change rate is greater or less than a predetermined multiple of the average value.

The abnormality determining means includes a change rate average value calculating means for calculating an average value of the change rate of the remaining capacity of each module battery, and the change rate of the remaining capacity of any module battery is calculated by the change rate average value calculating means. 3. The assembled battery device according to claim 2, which is means for determining that the voltage detection system abnormality of the module battery among the module battery detection means is outside a predetermined range including an average value of the calculated change rate.