JP4215556B2

JP4215556B2 - Judgment method and apparatus for capacity regulation electrode of lead battery

Info

Publication number: JP4215556B2
Application number: JP2003122743A
Authority: JP
Inventors: 俊二谷口; 義彰山口; 耕介原田
Original assignee: Kyushu Electric Power Co Inc; GS Yuasa Corp
Current assignee: Kyushu Electric Power Co Inc; GS Yuasa Corp
Priority date: 2003-04-25
Filing date: 2003-04-25
Publication date: 2009-01-28
Anticipated expiration: 2023-04-25
Also published as: JP2004327338A

Description

【０００１】
【発明の属する技術分野】
本発明は、電極表面が溶解・析出し、かつ電極表面に不活性な絶縁物が生じるタイプの鉛電池について、劣化した鉛電池の放電容量を規制している電極が正極か負極かを判定するための鉛電池の容量規制極の判定方法及び判定装置に関する。
【０００２】
【従来の技術】
従来、運転中の鉛電池の満充電状態を判定する手法はなく、又、鉛電池の容量を規制する電極を測定する手法はなかった。
【０００３】
そこで、本出願人は、特許文献１に示すように、鉛電池の充放電状態、残存容量等を直接測定を可能とする鉛電池の状態判定方法及びその装置を提案した。
【０００４】
この鉛電池の状態判定方法は、鉛電池を充電する際、充電途中において電流矩形パルスを印加し、その時生じる電池電圧波形の立ち上がりの傾き及び立下りの傾きの比が充電が進むに従い徐々に増加し、ピーク点を迎えた後、充電を終了させて放電末からの前記比の推移を、前記比を縦軸にし電気量を横軸にしてグラフ化して充電状態判定グラフを作成し、この充電状態判定グラフから電池の状態を判定するものである。
【０００５】
【特許文献１】
特開２００２−４４８８０号公報
【０００６】
【発明が解決しようとする課題】
これまでの電池の劣化極の判定は、運転中の鉛電池ではできず、電池を分解しないとわからなかった。また、一般に鉛電池では、過充電状態におかれると、正極が劣化する傾向にあり、また不足充電状態におかれると負極が劣化する傾向にあるため、劣化極を判定することで充電方法を変えて電池の長寿命化を図ることができる。
【０００７】
そこで、本発明は、鉛電池を分解することなく鉛電池の容量を規制する電極が正極か負極かを判定することができる鉛電池の容量規制電極の判定方法及び判定装置を提供するものである。
【０００８】
【課題を解決するための手段】
本発明の鉛電池の容量規制極の判定方法は、鉛電池を充電する際、充電量を増加させていく途中において電流矩形パルスを印加し、その時生じる電池電圧波形の立ち上がりの傾きの変化及び立下りの傾きの変化の推移を、前記傾きを縦軸にし電気量を横軸にしてグラフ化して立ち上がりの傾きのピーク点と立下りの傾きのボトム点を求め、さらにグラフの横軸での前記ピーク点と前記ボトム点が生じる位置を求め、前記位置から前記ピーク点が前記ボトム点より遅れて生じているときは負極が劣化し、前記ピーク点が前記ボトム点より先に生じているときは正極が劣化していると判定することを特徴とする。
【０００９】
また、本発明の鉛電池の容量規制極の判定装置は、正負の定電流矩形パルスを発生するパワー部と、鉛電池電圧波形の立ち上がり、立下りの状況のアナログ値をデジタル値に変換する信号処理部と、デジタル変換されたデータに基づき立ち上がりの傾きの変化及び立下りの傾きの変化の推移を、傾きを縦軸にし電気量を横軸にしてグラフ化して立ち上がりの傾きピーク点と立下りの傾きのボトム点を求め、さらにグラフの横軸での前記ピーク点と前記ボトム点が生じる位置を求め、前記位置から前記ピーク点が前記ボトム点より遅れて生じているときは負極が劣化し、前記ピーク点が前記ボトム点より先に生じているときは正極が劣化していると判定する容量規制極を判定する判定部と、前記パワー部から判断部までの全体システムを制御し、駆動信号を出力する制御部と、これらの判定結果を表示する表示部とを設けたことを特徴とする。
【００１０】
【発明の実施の形態】
鉛電池が劣化してくると正極または負極の劣化のどちらかで放電容量が規制される場合が多い。満充電近傍の立ち上がりの傾き（ｄＶａ／ｄｔ）の値は、正極で発生した酸素ガスの影響を受け、またたち下がりの傾き（ｄＶｂ／ｄｔ）の値は、負極の電気二重層容量の影響を支配的に受けることから、正負極の劣化状況を判定する目安とすることができる新しい知見を得た。
【００１１】
規制極の判定グラフは、鉛電池を充電する際、各充電途中において、電流矩形パルスを印加し、その時生じる鉛電池電圧波形の立ち上がりの傾き（ｄＶａ／ｄｔ）及び立下りの傾き（ｄＶｂ／ｄｔ）の推移をグラフ化することにより得られる。
【００１２】
規制極を判定するのに使用する判定グラフの作成について説明する。
【００１３】
図１はバイポーラ電源を用いた矩形パルス波印加の回路図である。図１において、２１は任意波形発生装置、２２は例えば−１００Ａから＋１００Ａの直流電流を出力するバイポーラ電源、２３はシャント、２４はスイッチ、２５は測定対象鉛電池、２６は記録計である。本例では、例えば、任意波形発生装置２１により、０．５秒の正（充電方向）、負（放電方向）の電流矩形パルスを作り、その後バイポーラ電源２２にて測定する電池定格の１．５Ｃの電流を作る。
【００１４】
この方法により作った電流矩形パルスを予め容量を測定した鉛電池に完全放電状態から、過充電状態まで０．１Ｃ程度で充電率を上げていき、任意の充電状態にて電流矩形パルスを印加し、そのとき生じる鉛電池電圧波形の立ち上がり及び立ち下がり状況を測定する。
【００１５】
図２は定電流矩形パルス印加時の電池電圧波形図である。図２に示すように、供試鉛電池の各充電状態での充放電矩形電流パルス印加時の鉛電池電圧波形の立ち上がりの傾き（ｄＶａ／ｄｔ）、立ち下がりの傾き（ｄＶｂ／ｄｔ）を測定し、その推移を傾きを縦軸、電流量（Ａｈ）を横軸にしてグラフ化すると、図３に示すように、電流量（Ａｈ）で充電するに従い、グラフにピーク点及びボトム点が表れる。
【００１６】
図３（ａ）に示すように、負極が劣化した場合、すなわち負極に電極反応に寄与できない不活性なＰｂＳＯ_４が蓄積する、いわゆるサルフェーション等により負極が劣化した場合は、満充電近傍の充電パルス印加により負極においてＨ_２ガス発生量が増え、負極と電解液の接触面積が減少する。これにより放電時の電気二重層容量が減少し、ｄＶｂ／ｄｔは上昇に転じ、早い段階でのようにボトム点が生じやすくなる。一方、ｄＶａ／ｄｔは正極で発生する穏やかなＯ_２ガスを負極で吸収し、生成されるＰｂＳＯ_４への再充電反応により減少に転じ、ピーク点を生じることから、ｄＶｂ／ｄｔのボトム点より遅れてピーク点が生じるものと考えられる。
【００１７】
これとは逆に、図３（ｂ）に示すように、正極側の劣化の場合、すなわち活物質の脱落や集電体の腐食等で実質の活物質（ＰｂＯ_２）量が減少する正極側の劣化の場合には、パルス印加時の充電電流密度が相対的に上昇するために、早い段階で急激にＯ_２ガスが発生してくる。この状況は負極でのガス吸収反応、即ちｄＶａ／ｄｔカーブのピーク点としてで捉えることができるため、結果としてｄＶａ／ｄｔのカーブのピーク点がｄＶｂ／ｄｔのボトム点より先に生じる。
【００１８】
以上のとおり、ｄＶａ／ｄｔのピーク点とｄＶｂ／ｄｔのボトム点の横軸の位置の前後関係により、劣化時の容量規制極を判定することができる。
【００１９】
【実施例】
図４は本発明による判定装置の一実施例を示すブロック図である。パワー部の１はＡＣ−ＤＣコンバータ、２は例えば−１００Ａ〜＋１００Ａの直流電流を出力するバイポーラ電源（シリーズレギュレータ）、３は測定鉛電池の電圧波形を信号変換処理して立ち上がりの傾きと立下りの傾きを測定する信号処理部、４は規制極の判定部、５は判定結果を表示する表示部である。判定装置全体は制御部６により制御される。
【００２０】
本実施例では、ＡＣ−ＤＣコンバータ１により、直流に変換した後、バイポーラ電源２により、０．５秒の正（充電方向）、負（放電方向）の電流矩形波で電流の大きさが、測定する鉛電池定格の１．５Ｃ（Ａ）の電流を作る。
【００２１】
この装置により作った矩形波を密閉型の鉛電池に完全放電状態から、０．１Ｃ（Ａ）で充電率を上げていき、充電途中の任意の充電状態にて電流矩形パルスを印加し、そのとき生じる電圧波形の立ち上がりの傾きｄＶａ／ｄｔ、立下りの傾きｄＶｂ／ｄｔを測定し、推移状況を記録しグラフ化する。このグラフがこの鉛電池の規制電極の判定グラフとなる。
【００２２】
実際に電気バスに（５６個）搭載した鉛電池（５６個、電池機種：１３５Ａｈ／３ＨＲ）を、約１年間過酷な使用環境下（走行距離：５７３９．６ｋｍ）で使用し、劣化させた電池を本装置で試験した結果、図３で示したように、ｄＶａ／ｄｔ、ｄＶｂ／ｄｔは、それぞれ満充電近傍において再充電反応及びガス発生によるピーク点、ボトム点が生じる。劣化するほどｄＶａ／ｄｔのピークが先鋭化してくるのは、負極でのガス吸収反応により生じたＰｂＳＯ_４が多く析出してくるためである。
【００２３】
この電池の放電時の容量制限極は、ピーク点がボトム点より先に生じているので、正極であると診断され実際に、この電池を解体し測定した結果、容量制限極は正極であり、診断結果と一致した。
【００２４】
【発明の効果】
上述したように、本発明によれば、電極が劣化した鉛電池に対して、電圧の立ち上がり、立下りの傾きを測定し、ピーク点、ボトム点の位置を求めるだけで、劣化した電極の判定が可能となる。
【図面の簡単な説明】
【図１】バイポーラ電源を用いた矩形パルス波印加の回路図である。
【図２】定電流矩形パルス印加時の電池電圧波形図である。
【図３】ｄＶａ／ｄｔのピーク点、ｄＶｂ／ｄｔのボトム点の説明図である。
【図４】本発明の判定装置のブロック図である。
【符号の説明】
１：ＡＣ−ｄＣコンバータ２：バイポーラ電源３：信号処理部４：判定部５：表示部２１：任意波形発生装置２２：バイポーラ電源２３：シャント２４：スイッチ２５：想定対象鉛電池２６：記録計[0001]
BACKGROUND OF THE INVENTION
The present invention determines whether an electrode that regulates the discharge capacity of a deteriorated lead battery is a positive electrode or a negative electrode for a lead battery in which the electrode surface dissolves and precipitates and an inert insulator is generated on the electrode surface. TECHNICAL FIELD The present invention relates to a determination method and a determination device for a capacity regulation pole of a lead battery.
[0002]
[Prior art]
Conventionally, there is no method for determining the fully charged state of a lead battery during operation, and there is no method for measuring an electrode that regulates the capacity of the lead battery.
[0003]
Therefore, as shown in Patent Document 1, the present applicant has proposed a lead battery state determination method and apparatus capable of directly measuring the charge / discharge state, remaining capacity, and the like of the lead battery.
[0004]
In this lead battery state determination method, when charging a lead battery, a current rectangular pulse is applied in the middle of charging, and the ratio of the rising slope and falling slope of the battery voltage waveform that occurs gradually increases as charging progresses. Then, after reaching the peak point, the charging is terminated, and the transition of the ratio from the end of discharge is graphed with the ratio as the vertical axis and the amount of electricity as the horizontal axis, and a charging state determination graph is created. The battery state is determined from the state determination graph.
[0005]
[Patent Document 1]
Japanese Patent Laid-Open No. 2002-44880 [0006]
[Problems to be solved by the invention]
Until now, the determination of the deterioration pole of a battery cannot be made with a lead battery in operation, and it has not been understood unless the battery is disassembled. In general, in a lead battery, the positive electrode tends to deteriorate when it is overcharged, and the negative electrode tends to deteriorate when it is undercharged. In other words, the battery life can be extended.
[0007]
Therefore, the present invention provides a determination method and a determination device for a capacity regulating electrode of a lead battery that can determine whether the electrode that regulates the capacity of the lead battery is a positive electrode or a negative electrode without disassembling the lead battery. .
[0008]
[Means for Solving the Problems]
According to the method for determining the capacity regulation electrode of a lead battery according to the present invention, when charging a lead battery, a current rectangular pulse is applied in the middle of increasing the amount of charge, and the change and rise of the rising slope of the battery voltage waveform generated at that time are applied. The transition of the change in the downward slope is graphed with the slope as the vertical axis and the quantity of electricity as the horizontal axis to obtain the peak point of the rising slope and the bottom point of the falling slope. Find the position where the peak point and the bottom point occur, when the peak point is delayed from the position, the negative electrode is deteriorated, when the peak point occurs before the bottom point It is determined that the positive electrode is deteriorated.
[0009]
In addition, the determination device for the capacity regulation pole of the lead battery according to the present invention includes a power unit that generates a positive and negative constant current rectangular pulse, and a signal that converts an analog value of a rising and falling state of the lead battery voltage waveform into a digital value. Based on the processing unit and digitally converted data, the rising slope change and the falling slope change are graphed with the slope as the vertical axis and the amount of electricity as the horizontal axis, and the rising slope peak point and the falling edge The bottom point of the slope is obtained, and further, the position where the peak point and the bottom point occur on the horizontal axis of the graph is obtained, and when the peak point is delayed from the position, the negative electrode deteriorates. A determination unit that determines a capacity regulation pole that determines that the positive electrode is deteriorated when the peak point occurs before the bottom point, and controls the entire system from the power unit to the determination unit. A control unit for outputting a driving signal, characterized in that a display unit for displaying these determination results.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
When lead batteries deteriorate, the discharge capacity is often regulated by either the positive electrode or the negative electrode. The rising slope (dVa / dt) value near the full charge is affected by the oxygen gas generated at the positive electrode, and the falling slope (dVb / dt) value is affected by the electric double layer capacity of the negative electrode. Since it received dominantly, the new knowledge which can be used as a standard which determines the deterioration condition of positive and negative electrodes was acquired.
[0011]
The regulation pole judgment graph shows that when a lead battery is charged, a current rectangular pulse is applied during each charge, and the rising slope (dVa / dt) and the falling slope (dVb / dt) of the lead battery voltage waveform generated at that time. ) In the form of a graph.
[0012]
The creation of a determination graph used to determine the regulation pole will be described.
[0013]
FIG. 1 is a circuit diagram of rectangular pulse wave application using a bipolar power supply. In FIG. 1, 21 is an arbitrary waveform generator, 22 is a bipolar power source that outputs a direct current of, for example, −100 A to +100 A, 23 is a shunt, 24 is a switch, 25 is a lead battery to be measured, and 26 is a recorder. In this example, for example, the arbitrary waveform generator 21 generates a positive (charge direction) and negative (discharge direction) current rectangular pulse of 0.5 seconds, and then measures the battery power of 1.5 C measured by the bipolar power supply 22. Make current.
[0014]
The current rectangular pulse produced by this method is applied to a lead battery whose capacity has been measured in advance from the fully discharged state to the overcharged state at about 0.1 C, and the current rectangular pulse is applied in any charged state. Measure the rise and fall situation of the lead battery voltage waveform that occurs at that time.
[0015]
FIG. 2 is a battery voltage waveform diagram when a constant current rectangular pulse is applied. As shown in FIG. 2, the rising slope (dVa / dt) and the falling slope (dVb / dt) of the lead battery voltage waveform when charging / discharging rectangular current pulses are applied in each charge state of the test lead battery are measured. Then, when the transition is graphed with the slope being the vertical axis and the current amount (Ah) being the horizontal axis, as shown in FIG. 3, the peak point and the bottom point appear in the graph as the current amount (Ah) is charged. .
[0016]
As shown in FIG. 3 (a), when the negative electrode is deteriorated, that is, when the negative electrode is deteriorated due to so-called sulfation or the like that accumulates inactive PbSO ₄ that cannot contribute to the electrode reaction, a charge pulse in the vicinity of full charge is obtained. When applied, the amount of H ₂ gas generated in the negative electrode increases, and the contact area between the negative electrode and the electrolyte decreases. As a result, the electric double layer capacity at the time of discharge decreases, dVb / dt starts to rise, and a bottom point is likely to occur as in the early stage. On the other hand, dVa / dt absorbs mild O ₂ gas generated at the positive electrode at the negative electrode and starts to decrease due to the recharge reaction to the generated PbSO ₄ , resulting in a peak point. From the bottom point of dVb / dt It is considered that a peak point occurs with a delay.
[0017]
On the contrary, as shown in FIG. 3B, in the case of deterioration on the positive electrode side, that is, on the positive electrode side where the amount of the active material (PbO ₂ ) is reduced due to dropping of the active material or corrosion of the current collector. In the case of deterioration, since the charging current density at the time of pulse application is relatively increased, O ₂ gas is rapidly generated at an early stage. This situation can be grasped as a gas absorption reaction at the negative electrode, that is, as the peak point of the dVa / dt curve. As a result, the peak point of the dVa / dt curve occurs before the bottom point of the dVb / dt.
[0018]
As described above, the capacity regulation pole at the time of deterioration can be determined based on the front and back relationship between the horizontal axis positions of the dVa / dt peak point and the dVb / dt bottom point.
[0019]
【Example】
FIG. 4 is a block diagram showing an embodiment of the determination apparatus according to the present invention. The power section 1 is an AC-DC converter, 2 is a bipolar power supply (series regulator) that outputs a direct current of, for example, −100 A to +100 A, and 3 is a signal conversion process for the voltage waveform of the measured lead battery to rise and fall A signal processing unit for measuring the inclination of the reference numeral 4, a determination unit 4 for the regulation pole, and a display unit 5 for displaying the determination result. The entire determination apparatus is controlled by the control unit 6.
[0020]
In the present embodiment, after being converted into direct current by the AC-DC converter 1, the magnitude of the current is positive (charge direction) and negative (discharge direction) current rectangular waves of 0.5 seconds by the bipolar power supply 2. A current of 1.5 C (A) of the lead battery rating to be measured is made.
[0021]
The rectangular wave made by this device is discharged from a completely discharged state to a sealed lead battery at 0.1 C (A), and a current rectangular pulse is applied in an arbitrary charging state during charging. The rising slope dVa / dt and falling slope dVb / dt of the voltage waveform that occurs are measured, and the transition state is recorded and graphed. This graph is a determination graph of the regulation electrode of this lead battery.
[0022]
Batteries deteriorated by using lead batteries (56 batteries, battery type: 135Ah / 3HR) actually mounted on an electric bus (56 batteries) under harsh usage conditions (travel distance: 5739.6 km) for about one year As a result of testing with this apparatus, as shown in FIG. 3, dVa / dt and dVb / dt have a peak point and a bottom point due to recharge reaction and gas generation near full charge, respectively. The reason why the peak of dVa / dt sharpens as it deteriorates is that a large amount of PbSO ₄ produced by the gas absorption reaction at the negative electrode is precipitated.
[0023]
Since the capacity limit electrode at the time of discharge of this battery is generated before the bottom point, the peak point is diagnosed as being a positive electrode, and the result of actually disassembling and measuring this battery shows that the capacity limit electrode is a positive electrode. Consistent with diagnostic results.
[0024]
【The invention's effect】
As described above, according to the present invention, for a lead battery in which the electrode has deteriorated, the rising and falling slopes of the voltage are measured, and the position of the peak point and the bottom point is determined. Is possible.
[Brief description of the drawings]
FIG. 1 is a circuit diagram of rectangular pulse wave application using a bipolar power supply.
FIG. 2 is a battery voltage waveform diagram when a constant current rectangular pulse is applied.
FIG. 3 is an explanatory diagram of a peak point of dVa / dt and a bottom point of dVb / dt.
FIG. 4 is a block diagram of a determination apparatus according to the present invention.
[Explanation of symbols]
1: AC-dC converter 2: Bipolar power supply 3: Signal processing unit 4: Determination unit 5: Display unit 21: Arbitrary waveform generator 22: Bipolar power supply 23: Shunt 24: Switch 25: Assumed lead battery 26: Recorder

Claims

When charging a lead battery, a current rectangular pulse is applied in the middle of increasing the amount of charge, and the change of the rising slope and the falling slope of the battery voltage waveform that occurs at that time is represented by the vertical axis representing the slope. The amount of electricity is plotted on the horizontal axis to determine the peak point of the rising slope and the bottom point of the falling slope, and the position where the peak point and the bottom point occur on the horizontal axis of the graph is determined. When the peak point occurs later than the bottom point, the negative electrode is deteriorated, and when the peak point occurs earlier than the bottom point, it is determined that the positive electrode is deteriorated. Judgment method of capacity regulation pole of lead battery.

A power unit that generates positive and negative constant current rectangular pulses, a signal processing unit that converts analog values of the rising and falling states of the lead battery voltage waveform into digital values, and changes in the rising slope based on the digitally converted data And the transition of the change in the slope of the fall is graphed with the slope as the vertical axis and the quantity of electricity as the horizontal axis to obtain the rising slope peak point and the falling slope bottom point. Find the position where the peak point and the bottom point occur, when the peak point is delayed from the position, the negative electrode is deteriorated, when the peak point occurs before the bottom point A determination unit that determines a capacity regulation electrode that determines that the positive electrode is deteriorated, a control unit that controls the entire system from the power unit to the determination unit and outputs a drive signal, and the determination results Determining device capacity regulating pole lead batteries, characterized in that a display unit for displaying.