JPH10132911A - Residual capacity meter for battery - Google Patents

Residual capacity meter for battery

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Publication number
JPH10132911A
JPH10132911A JP28392096A JP28392096A JPH10132911A JP H10132911 A JPH10132911 A JP H10132911A JP 28392096 A JP28392096 A JP 28392096A JP 28392096 A JP28392096 A JP 28392096A JP H10132911 A JPH10132911 A JP H10132911A
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Prior art keywords
battery
current
voltage
sensor
residual capacity
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Pending
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JP28392096A
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Japanese (ja)
Inventor
Kiyomitsu Ishikawa
Tomohiro Yamaguchi

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Stanley Electric Co Ltd
スタンレー電気株式会社
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Abstract

PROBLEM TO BE SOLVED: To provide a residual capacity meter which is very accurate and easy to use, by eliminating requirement that a battery is fully charged before using it, and preventing charging error from occurring.
SOLUTION: The residual capacity meter 1 for a battery comprises a current sensor 2 which measures charge/discharge current of a battery 10, a voltage sensor 3 which measures battery voltage, and a control/judge circuit 4 which reads outputs from the current sensor 2 and the voltage sensor 3 and processes relation between current and voltage as a linear relational expression depending on battery's residual capacity. The residual capacity meter 1 compares current and voltage which are respectively measured with the current sensor and the voltage sensor to the relational expression in the control/judge circuit and derives residual capacity (Q). Therefore, traditional process that the battery is fully charged before using it and residual capacity is calculated by reducing total used amount from initial amount is not required.

Description

【発明の詳細な説明】 DETAILED DESCRIPTION OF THE INVENTION

【０００１】 [0001]

【発明の属する技術分野】本発明は、電気自動車などバッテリーで駆動されている機器において、バッテリーの充電量の残容量を計測して告知し、使用者に対し以後の使用可能時間に対する目安を与えたり、或いは、充電時期を告知するために用いられるバッテリー残容量計に関するものである。 BACKGROUND OF THE INVENTION The present invention provides a device that is driven by a battery such as electric vehicles, the remaining capacity of the battery charge announced measures, giving a measure for the subsequent available time to the user or, alternatively, the present invention relates to a battery remaining capacity meter that is used to announce the charging time.

【０００２】 [0002]

【従来の技術】従来のこの種の残容量計においては、使用開始時にはバッテリーが１００％の充電（満充電）が行われているものと仮定し、使用による放電電流値を電流センサにより計測して積算し、この積算値を逐次に満充電量から減算していくことで、使用過程における残容量を演算するものであった。 BACKGROUND OF THE INVENTION In this type of conventional residual capacity meter, assuming the use start charging the battery is 100% at the time (full charge) is performed, the discharge current value by using the measured by a current sensor integration Te, and that will subtract the accumulated value successively from the fully charged amount was achieved, thereby calculating the remaining capacity in the course of use.

【０００３】 [0003]

【発明が解決しようとする課題】しかしながら、前記した従来の残容量計では、先ず第一には、例えば周囲温度、使用年数などバッテリーの使用状態により能力が変動するものであるので、使用開始時の１００％の充電量の正確な設定が困難であり、この設定が適正でない場合、計測値に誤差を生じる問題点がある。 [SUMMARY OF THE INVENTION However, in the conventional remaining capacity meter described above, first, the first, for example ambient temperature, since the capacity by the use condition of the battery, such as years of use is to change, at the start of use 100% of the charge amount precise setting of a difficult, if this setting is not proper, there is a problem causing an error in the measurement value.

【０００４】また第二には、放電電流値を積算するものであるので、電流センサに僅かでも誤差があるときには、その誤差も積算されて大きな値となり、結果として計測値に誤差を生じる問題点があり、更に第三には、バッテリー自体が放電電流の大きさにより容量が変動するなど動的な特性を有するものであるので、単に放電電流を積算したのみでは上記の特性とに解離を生じる問題点もあり、これらの点の解決が課題とされるものとなっている。 [0004] Secondly, since those for integrating the discharge current value, when there is an error even slightly to the current sensor, the error becomes a large value is accumulated, causing an error in the measurement value as a result problems There is, further third, because the battery itself and has a dynamic characteristic such as capacitance by the magnitude of the discharge current varies, resulting in dissociation into the above characteristics than simply only by integrating the discharge current There is also a problem, and is intended to solve these points are a problem.

【０００５】 [0005]

【課題を解決するための手段】本発明は前記した従来の課題を解決するための具体的な手段として、バッテリーの充放電電流を計測する電流センサと、そのときのバッテリー電圧を計測する電圧センサと、前記電流センサと電圧センサとからの出力を読み込むと共に、バッテリーの残容量をパラメータとしたときの電流と電圧との関係を一次の関係式として保持する制御／判定回路とから成り、前記電流センサと電圧センサとで計測した電流および電圧と前記制御／判定回路内の関係式とを比較して残容量を得ることを特徴とするバッテリー残容量計を提供することで課題を解決するものである。 As specific means for the present invention SUMMARY OF THE INVENTION The to solve the conventional problems described above, a current sensor for measuring a charge and discharge current of the battery, a voltage sensor for measuring the battery voltage at that time when the reads in the output from the current sensor and the voltage sensor consists of a control / decision circuit for holding the remaining capacity of the battery the relationship between the current and the voltage when a parameter as a primary relation, the current solves the problem by compared sensor and a voltage sensor and the current and voltage measured by the equation of the control / judgment in the circuit to provide a battery remaining capacity meter, characterized in that to obtain the remaining capacity is there.

【０００６】 [0006]

【発明の実施の形態】つぎに、本発明を図に示す実施形態に基づいて詳細に説明する。 DETAILED DESCRIPTION OF THE INVENTION Next will be described in detail with reference to embodiments shown in the figures the present invention. 図１に符号１で示すものは本発明に係るバッテリー残容量計であり、このバッテリー残容量計１は本発明により電流センサ２と電圧センサ３と制御／判定回路４とから構成されている。 Those indicated by reference numeral 1 in FIG. 1 is a battery remaining capacity meter according to the present invention, and a current sensor 2 and the voltage sensor 3 control / determination circuit 4 which by the remaining battery capacity meter 1 according to the present invention.

【０００７】ここで、前記電流センサ２はバッテリー１ [0007] In this case, the current sensor 2 is battery 1
０と負荷１１との間に設置されて、このバッテリー１０ 0 is installed between the load 11, the battery 10
の充放電電流を計測するものとされ、前記電圧センサ３ It is intended to measure the charging and discharging current, the voltage sensor 3
は前記電流センサ２が充放電電流を計測している時点でのバッテリー１０の端子間電圧を測定するものとされ、 Is intended is to measure the terminal voltage of the battery 10 at the time of the current sensor 2 measures the charging and discharging current,

【０００８】次いで、以上の構成とした本発明のバッテリー残容量計１の動作について説明を行う。 [0008] Then, the remaining battery capacity meter 1 of the operation of the present invention with the above configuration will be described. 図２のグラフは本発明によるバッテリー１０の残容量測定の原理を示すものであり、前記バッテリー１０においては、残容量をパラメータとして電流値とそのときの電圧値とを測定すると、それぞれの残容量負荷曲線Ｌ 0 〜Ｌ 100は交わらず、且つ、各負荷曲線Ｌ 0 〜Ｌ 100 （残容量＝０％ The graph of Figure 2 shows the principle of a remaining capacity measurement of the battery 10 according to the present invention, in the battery 10, when measuring the current value and the voltage value at that time the remaining capacity as a parameter, each of the remaining capacity load curve L 0 ~L 100 is not intersect, and each load curve L 0 ~L 100 (remaining capacity = 0%
〜１００％）は直線状であり一次式で近似できることに着目し本発明は行われている。 100%) of the focused present invention can be approximated by a linear first-order equation is performed.

【０００９】即ち、図２において、残容量負荷曲線Ｌ [0009] That is, in FIG. 2, the remaining capacity load curve L
100 （残容量＝１００％）を例として説明を行えば、この残容量負荷曲線Ｌ 100は一次式（Ｅ 100 ＝Ａ 100 Ｉ＋ 100 by performing the described as an example (the remaining capacity = 100%), the remaining capacity load curve L 100 is a linear equation (E 100 = A 100 I +
100 ）として近似させることが可能であり、同様に残容量負荷曲線Ｌ 80は一次式（Ｅ 80 ＝Ａ 80 Ｉ＋Ｂ 80 ）として近似させることが可能であり、その他の残容量曲線についても同様である。 B 100) it is possible to approximate as likewise remaining capacity load curve L 80 is can be approximated as a linear equation (E 80 = A 80 I + B 80), the same applies for the other remaining capacity curve is there.

【００１０】従って、図３に示すように、それぞれの残容量負荷曲線Ｌ 0 〜Ｌ 100毎の傾き（Ａ 0 〜Ａ 100 ）と電圧軸との交点（Ｂ 0 〜Ｂ 100 ）とを求めて制御／判定回路４中に予めに保持しておき、例えば負荷１１に対しての放電電流Ｉとそのときの電圧値Ｅとを測定した測定点Ｐが何れの残容量負荷曲線Ｌ 0 〜Ｌ 100を近似する一次式の解となるかを判定すれば、残容量を知ることができるものとなる。 Accordingly, as shown in FIG. 3, seeking the intersection of each of the remaining capacity load curve L 0 ~L 100 each slope (A 0 ~A 100) and the voltage axis (B 0 ~B 100) control / determination circuit advance retained in 4, such as the discharge current I and the voltage value E and the one measurement point P that is measured remaining capacity when the load of the load 11 curve L 0 ~L 100 When it is determined whether the solution of the linear expression that approximates a, and that it is possible to know the remaining capacity.

【００１１】尚、現実にはバッテリー１０には各種の定格容量Ｃのものが存在するので、各容量のもの毎に上記の各曲線Ｌ 0 〜Ｌ 100を求めても良いが、それではあまりに煩雑なものとなるので、本発明では図２における横軸を、電流センサ２で測定された実際の電流値Ｉをバッテリーの定格容量Ｃで除すことで比率化し、全ての定格容量に対応できるものとしている。 [0011] It should be noted that, because the reality is in the battery 10 there are those of a variety of rated capacity C, and may be obtained each of the above curve L 0 ~L 100 for each one of each capacity, So Too complicated since the things, the horizontal axis in FIG. 2 in the present invention, as the actual current value I measured by the current sensor 2 is ratioed by dividing the battery rated capacity C, can cope with all the rated capacity there.

【００１２】図４のフローチャートは上記の判定手順を一層に詳細に示すものであり、先ず、測定を目的とするバッテリー１０の定格容量Ｃを予めに制御／判定回路４ [0012] the flow chart of FIG. 4 shows in more detail the above judgment procedure, first, pre-control / determination circuit rated capacity C of the battery 10 for the purpose of measurement 4
に入力する。 Input to. これは、上記に説明したように電流センサ２で測定された実際の電流値をバッテリー１０の定格容量に対応させるためである。 This is to adapt the actual current value measured by the current sensor 2 as described above rated capacity of the battery 10. 続いて、制御／判定回路４ Subsequently, the control / decision circuit 4
は電流センサ２と電圧センサ３とを駆動しバッテリー１ Battery 1 drives a current sensor 2 and the voltage sensor 3
０の電流値Ｉと、そのときのバッテリー１０の電圧値Ｅ 0 and the current value I of the voltage value E of the battery 10 at that time
とを測定（図中にステップ１で示す）する。 Preparative the measured (shown in Step 1 in the figure).

【００１３】このときに、例えばバッテリー１０が電気自動車用である場合の惰力走行時或いは降坂時などで、 [0013] In this case, for example, the battery 10 and coasting or during downhill at the time when it is for electric vehicles,

【００１４】また、測定した電流値Ｉが所定の範囲内である場合には、制御／判定回路４はこれらの値を内部に取り込み判定を行う。 Further, when the measured current value I is within a predetermined range, the control / decision circuit 4 makes a determination captures these values ​​therein. このときには、電流値Ｉを定格容量Ｃで除し比率化した後に、先ず、残容量負荷曲線Ｌ 0 In this case, after the ratio of dividing the current value I at the rated capacity C, first, the remaining capacity load curve L 0
を近似する一次式（Ｅ 0 ＝Ａ 0 Ｉ＋Ｂ 0 ）に代入して算定電圧値Ｅ 0を求める（ステップ３）。 Linear expression that approximates a (E 0 = A 0 I + B 0) assigned to to determine the estimated voltage value E 0 (Step 3).

【００１５】しかる後に、制御／判定回路４は上記計算電圧値Ｅ 0と、電圧センサ３で実際に計測された電圧値Ｅとを比較し（ステップ４）、もしも、算定電圧値Ｅ 0 [0015] Thereafter, the control / decision circuit 4 and the calculated voltage value E 0, compares the voltage value E which are actually measured by the voltage sensor 3 (step 4), if, calculated voltage value E 0
≧電圧値Ｅであれば、バッテリー１０の残容量Ｑは０％ If ≧ voltage value E, the remaining capacity Q of the battery 10 is 0%

【００１６】また、上記の比較の結果が算定電圧値Ｅ 0 [0016] In addition, results are calculated voltage value of the above comparison E 0
＜電圧値Ｅである場合には、バッテリー１０にはより以上の残容量Ｑがあることと成るので、制御／判定回路４ <When a voltage E is so composed and that there is more than a remaining capacity Q in the battery 10, the control / decision circuit 4
は残容量負荷曲線Ｌ 20を近似する一次式（Ｅ 20 ＝Ａ 20 Linear expression that approximates the residual capacity load curve L 20 is (E 20 = A 20 I
＋Ｂ 20 ）に代入して算定電圧値Ｅ 20を求め、算定電圧値Ｅ 20と電圧値Ｅとを比較する。 + B 20) to calculate a voltage value E 20 by substituting the determined and compares the calculated voltage value E 20 and a voltage value E.

【００１７】このように算定電圧値Ｅ 20 →Ｅ 40 →Ｅ 60と比較して行き、例えば算定電圧値Ｅ 60で電圧値Ｅと一致すれば、このときのバッテリー１０の残容量Ｑは６０％ [0017] Thus calculated voltage value E 20 → E 40 → E 60 and continue to compare, match the voltage E of, for example, calculate a voltage value E 60, the remaining capacity Q of the battery 10 at this time is 60%
であると判定できるので、制御／判定回路４はこの残容量Ｑを表示する。 It can be determined to be the control / determination circuit 4 displays the remaining capacity Q. また、もしも、算定電圧値Ｅ 60 ＜電圧値Ｅであり、算定電圧値Ｅ 80 ＞電圧値Ｅであれば、残容量Ｑは６０％から８０％の間にあるものと成る。 Moreover, if, <a voltage value E, calculated voltage value E 80> calculated voltage value E 60 if the voltage value E, the remaining capacity Q is made as being between 60% to 80%.

【００１８】この場合、算定電圧値Ｅ 80と算定電圧値Ｅ [0018] In this case, the calculated voltage value E 80 and the calculated voltage value E
60との間の中間電圧値ｅを算定電圧値Ｅ 80から算定電圧値Ｅ 60を減じることで求め、この中間電圧値ｅを２０等分すれば、この区間における１％刻みの残容量ｑが近似的に得られるものとなるので、制御／判定回路４は残容量（Ｑ＋ｑ）を演算し、これを表示（ステップ５）する。 Calculated by subtracting the estimated voltage value E 60 the intermediate voltage value e, the calculation voltage value E 80 between 60, if the intermediate voltage value e 20 equal parts, the remaining capacity q of 1% increments in the interval since those obtained approximately, the control / decision circuit 4 calculates a remaining capacity (Q + q), and displays it (step 5).

【００１９】次いで、上記の構成とした本発明のバッテリー残容量計１の作用及び効果について説明する。 [0019] Next, a description will be given battery remaining capacity meter 1 of the action and effects of the present invention with the above configuration. 本発明により残容量負荷曲線Ｌ（ 0100 ）に基づいてバッテリー１０の残容量を演算する構成としたことで、バッテリー１０に例えば劣化、気温低下などによる容量低下を生じている場合、満充電を行った状態でも残容量負荷曲線Ｌは、その容量低下に応じるものとなる。 By the present invention has a configuration that calculates the remaining capacity of the battery 10 based on the remaining capacity load curve L (0 ~ 100), for example degraded battery 10, when occurring the capacity reduction due to temperature lowering, fully charged remaining capacity load curve L even when subjected to becomes that respond to its capacity reduced.

【００２０】従って、本発明のバッテリー残容量計１は常に計測時点におけるバッテリー１０の残容量を表示するものとなり、従来例のごとくに満充電からの使用量の積算により推定するものではないので、初期値の誤差、 [0020] Therefore, the battery remaining capacity meter 1 of the present invention is always shall indicate the remaining capacity of the battery 10 in the measurement time, because it is not intended to be estimated by integration of the amount of the full charge in the conventional example as described, the initial value of the error,

【００２１】 [0021]

【発明の効果】以上に説明したように本発明により、バッテリーの充放電電流を計測する電流センサと、そのときのバッテリー電圧を計測する電圧センサと、前記電流センサと電圧センサとからの出力を読み込むと共に、バッテリーの残容量をパラメータとしたときの電流と電圧との関係を一次の関係式として保持する制御／判定回路とから成り、前記電流センサと電圧センサとで計測した電流および電圧と前記制御／判定回路内の関係式とを比較して残容量を得るバッテリー残容量計としたことで、 The present invention described above, according to the present invention, a current sensor for measuring a charge and discharge current of the battery, and a voltage sensor for measuring the battery voltage at that time, the output from said current sensor and the voltage sensor reads in the remaining capacity of the battery the relationship between the current and the voltage when a parameter consists of a control / decision circuit for holding a primary relation, the current sensor and the current and voltage measured by the voltage sensor and by comparing the relation in the control / determination circuit that has a battery remaining capacity meter to obtain the remaining capacity,

【００２２】また第二には、上記使用量の積算値を不要としたことで、例えば電流センサに誤差があるときには、その誤差も積算され、最終的には大きな誤差となり測定が不正確となるなども解消し、精度の向上に優れた効果を奏する。 [0022] Secondly, by the unnecessary an integrated value of the amount, when there is an error, for example, current sensor, the error is also integrated, the inaccurate measurement becomes large errors eventually also eliminated, such as, an excellent effect on the accuracy of the. 更に第三には、負荷電流の大小によるバッテリーの容量変化などの影響も受けないものとして精度の向上に優れた効果を奏するものである。 More Third, in which excellent effects to improve the accuracy of as not influenced, such as the capacitance change of the battery caused by the magnitude of the load current.

【００２３】また、電流センサで測定した電流値をバッテリーの定格容量値で除した値を演算時の電流値とするバッテリー残容量計としたことで、バッテリーの定格容量毎に残容量負荷曲線などのを設定することを不要とし、一種類の残容量負荷曲線で全ての定格容量値に対応できるものとし、構成の簡素化にも優れた効果を併せて奏するものとなる。 Further, it was a battery remaining capacity meter according to the current value during operation value obtained by dividing the rated capacitance of the battery current value measured by the current sensor, each rated capacity of the battery such as the remaining capacity load curve is unnecessary to set from, and be able to handle all of the rated capacity value of one kind of the remaining capacity load curve becomes exert together an excellent effect in simplifying the configuration.

【図面の簡単な説明】 BRIEF DESCRIPTION OF THE DRAWINGS

【図１】 本発明に係るバッテリー残容量計の実施形態を示すブロック図である。 1 is a block diagram illustrating an embodiment of a battery remaining capacity meter according to the present invention.

【図２】 同じバッテリー残容量計の測定原理を示すグラフである。 2 is a graph showing the measurement principle of the same remaining battery capacity meter.

【図３】 同じバッテリー残容量計の残容量負荷曲線を近似する一次式の係数項と定数項との例を示す表である。 3 is a table showing an example of the coefficient term and the constant term of the linear expression that approximates the residual capacity load curve of the same remaining battery capacity meter.

【図４】 同じバッテリー残容量計の動作を示すフローチャートである。 4 is a flowchart showing the operation of the same remaining battery capacity meter.

【符号の説明】 DESCRIPTION OF SYMBOLS

１……バッテリー残容量計 ２……電流センサ ３……電圧センサ ４……制御／判定回路 １０……バッテリー １１……負荷 Ｉ……電流値 Ｅ……電圧値 Ｑ……残容量 Ｌ 0 〜Ｌ 100 ……残容量負荷曲線 Ｅ 0 〜Ｅ 100 ……算定電圧値 1 ...... battery remaining capacity meter 2 ...... current sensor 3 ...... Voltage sensor 4 ...... control / determination circuit 10 ...... battery 11 ...... load I ...... current value E ...... voltage value Q ...... remaining capacity L 0 ~ L 100 ...... remaining capacity load curve E 0 ~E 100 ...... calculated voltage value

Claims (2)

【特許請求の範囲】 [The claims]
1. 【請求項１】 バッテリーの充放電電流を計測する電流センサと、そのときのバッテリー電圧を計測する電圧センサと、前記電流センサと電圧センサとからの出力を読み込むと共に、バッテリーの残容量をパラメータとしたときの電流と電圧との関係を一次の関係式として保持する制御／判定回路とから成り、前記電流センサと電圧センサとで計測した電流および電圧と前記制御／判定回路内の関係式とを比較して残容量を得ることを特徴とするバッテリー残容量計。 And 1. A current sensor for measuring the battery charge and discharge current, and a voltage sensor for measuring the battery voltage at that time, the read output from said current sensor and the voltage sensor, and a remaining capacity of the battery parameters It was composed of a control / decision circuit for holding relationship as the primary relationship between current and voltage when, a relational expression of the control / judgment in the circuit the current and voltage measured by said current sensor and the voltage sensor remaining battery capacity meter, characterized in that to obtain the remaining capacity compared to.
2. 【請求項２】 前記電流センサで測定した電流値をバッテリーの定格容量値で除した値を演算時の電流値とすることを特徴とする請求項１記載のバッテリー残容量計。 2. A battery remaining capacity meter according to claim 1, characterized in that the current value during operation a value obtained by dividing the current value measured by the current sensor at the rated capacitance of the battery.
JP28392096A 1996-10-25 1996-10-25 Residual capacity meter for battery Pending JPH10132911A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP28392096A JPH10132911A (en) 1996-10-25 1996-10-25 Residual capacity meter for battery

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP28392096A JPH10132911A (en) 1996-10-25 1996-10-25 Residual capacity meter for battery

Publications (1)

Publication Number Publication Date
JPH10132911A true true JPH10132911A (en) 1998-05-22

Family

Family Applications (1)

Application Number Title Priority Date Filing Date
JP28392096A Pending JPH10132911A (en) 1996-10-25 1996-10-25 Residual capacity meter for battery

Country Status (1)

JP (1) JPH10132911A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001229981A (en) * 1999-12-16 2001-08-24 Daimlerchrysler Ag Remaining electric charge of battery and method of monitoring power function
US6441619B1 (en) 2000-07-28 2002-08-27 Honda Giken Kogyo Kabushiki Kaisha Remaining charge detection device for power storage unit
JP2005331518A (en) * 2005-05-30 2005-12-02 Furukawa Battery Co Ltd:The Residual capacity measurement method and device for storage battery mounted on vehicle
JP2011026993A (en) * 2009-07-23 2011-02-10 Denso Corp Automatic stop/start device for internal combustion engine

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001229981A (en) * 1999-12-16 2001-08-24 Daimlerchrysler Ag Remaining electric charge of battery and method of monitoring power function
US6441619B1 (en) 2000-07-28 2002-08-27 Honda Giken Kogyo Kabushiki Kaisha Remaining charge detection device for power storage unit
JP2005331518A (en) * 2005-05-30 2005-12-02 Furukawa Battery Co Ltd:The Residual capacity measurement method and device for storage battery mounted on vehicle
JP4652891B2 (en) * 2005-05-30 2011-03-16 古河電気工業株式会社 Residual capacity measuring method and apparatus of a storage battery mounted on the vehicle
JP2011026993A (en) * 2009-07-23 2011-02-10 Denso Corp Automatic stop/start device for internal combustion engine

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