JP2004343936A - Charging device and charging method for secondary battery - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a charging device and a charging method that can rapidly and surely perform charging till full charging by constituting the device so as to automatically determine a type or the like of a secondary battery in a charging process, and without causing an excessive chemical reaction (redox reaction). <P>SOLUTION: The secondary battery 1 is charged with a lower prescribed charging application voltage value E<SB>sl</SB>, and a voltage value e of the secondary battery 1 is detected during the charging. When the voltage value e is not higher than the voltage value E<SB>s1</SB>, the application voltage is switched to lower full-charging equilibrium potential E<SB>eql</SB>, and a current value i flowing to the secondary battery 1 is detected during the switching, and when the current value i is not higher than a charging completion reference value J, charging is stopped. On the other hand, when the voltage value e is higher than the voltage value E<SB>sl</SB>, the secondary battery is charged by switching the application voltage to a higher prescribed charging application voltage value E<SB>sh</SB>. After that, the application voltage is switched to full-charging equilibrium potential E<SB>eqh</SB>, thus detecting the current value i flowing to the secondary battery 1 during the switchings. When the current value i is not higher that the full-charging completion reference value J, the charging is stopped. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【００４０】
また、負極の反応は、次の一般式（化学反応式）で表される。
【００４１】
【化２】

【００４２】
放電において前記正極の反応では、オキシ水酸化ニッケル（Ｎｉ（ＯＯＨ））と水（Ｈ_２Ｏ）、および正極からの電子（ｅ⁻）が反応して、水酸化ニッケル（Ｎｉ（ＯＨ）_２）が生成し、一方、負極の反応では、カドミウム（Ｃｄ）が、正極で生成されセパレータを透過した水酸化イオン（ＯＨ⁻）と反応して、水酸化カドミウム（Ｃｄ（ＯＨ）_２）と電子（ｅ⁻）を生成し、この電子（ｅ⁻）は外部負荷を通過して正極へ供給される。
【００４３】
前記サイクルで電子（ｅ⁻）が外部負荷を通過する過程で仕事として利用される。従って、このサイクルが上手く回るということは、正極に水（Ｈ_２Ｏ）が豊富にあり、生成物である水酸化ニッケル（Ｎｉ（ＯＨ）_２）の濃度が低く、負極では水酸化カドミウム（Ｃｄ（ＯＨ）_２）の濃度が低いことである。これを数式で表現すると次式（数式（１））となる。
【００４４】
【数１】

【００４５】
ここで、Ｅ^０は標準起電力であり、正極、負極を構成する物質によって決まる定数で、それらの量には依存しない。ニッケル−カドミウム電池の場合、この標準起電力Ｅ^０は約１．２〔Ｖ（ボルト）〕である。また、Ｒは気体定数、Ｔは絶対温度、Ｆはファラデー数である。
【００４６】
前記数式（１）が示すように、正極では水（Ｈ_２Ｏ）の濃度Ｃ_ａｑが高く、水酸化ニッケル（Ｎｉ（ＯＨ）_２）の濃度Ｃ_Ｎが低いほど、起電力Ｅ_ｅｍｆは大きくなり、負極では水酸化カドミウム（Ｃｄ（ＯＨ）_２）の濃度Ｃ_Ｃが低いほど、起電力Ｅ_ｅｍｆは大きくなる。起電力Ｅ_ｅｍｆが大きいことは、蓄電量が大きいことである。
【００４７】
ところで、二次電池１の充電状態を的確に知るには、図２に示す回路を形成すればよい。すなわち、二次電池１に可変電源１１を接続し、この可変電源１１の電位を、二次電池１の起電力Ｅと平衡する電位に調整する。すなわち、電流検出部３による検出電流が±０〔ｍＡ（ミリアンペア）〕となるように可変電源１１を調整し、これにより二次電池１の起電力Ｅ_ｅｍｆを間接的に測定する。こうして、二次電池１の満充電状態での起電力Ｅ_ｅｍｆを、各種類、又は各機種ごとに測定して、そのデータを前記プログラム・演算制御部４の記憶手段に入力しておく。
【００４８】
次に、本発明の充電方法を説明する上で基本となる二次電池１の充電電圧と充電電流との特性について、図３のグラフに基づいて説明する。
図３におけるグラフの横軸には電池端子電圧を、また縦軸には充電電流をとっており、充電率が異なる各二次電池１の電圧一電流特性をそれぞれ示している。
【００４９】
すなわち、図３における破線で示す曲線は、二次電池１の充電率が略０％の状態（電池がなくなった状態）を示しており、この場合は標準電圧Ｅ^０（公称電圧）より低い電圧Ｅ_αを印加しても充電電流が流れ出す。また、印加電圧を開放電圧Ｅ_αから上昇させていくにつれて、略それに比例して二次電池１に流れる充電電流も増大するが、所定の電圧（電圧一電流曲線における変曲点）を過ぎると、印加電圧に対する充電電流の増加率（ΔＩ／ΔＥ）は減少し、やがて、印加電圧を上昇させても充電電流は殆ど上昇しなくなり、充電電流は電流ピーク値Ｉ_ｓｏに到達する。
【００５０】
この（印加電圧に対する充電電流の増加率（ΔＩ／ΔＥ）が０となったとき）の電流ピーク値Ｉ_ｓｏに対応する印加電圧値はＥ_ｓとなり、この所定の充電印加電圧値Ｅ_ｓは二次電池１の種類や二次電池１の劣化状態などによって決まる二次電池１に固有の電圧値となる。この後、さらに印加電圧を上昇させても、充電電流はしばらくはＩ_ｓｏのままで上昇はしないが、二次電池１の内部で負性抵抗特性が現れて、急激な温度上昇を来たすようになり、やがて、充電電流は印加電圧の上昇に伴って、再び上昇し始める。
【００５１】
この充電率が略０％の二次電池１に印加する印加電圧が前記所定の充電印加電圧値Ｅ_ｓを越えると、該二次電池１は、内部で活物質の酸化還元反応がさらに進んで、電気分解反応を惹き起こす不可逆化学反応領域Ｄに突入する。
また、図３の一点鎖線で示す充電率が約５０％の二次電池１では、印加電圧を（０〔Ｖ〕から）上昇させていったときに二次電池１に充電電流が流れ始める開放電圧Ｅ_βは、充電率が略０％の二次電池１の開放電圧Ｅ_αよりも高くなる。この開放電圧は二次電池１の充電率が上昇するに連れて高くなり、図３の二点鎖線で示す充電率が約９０％の二次電池１の開放電圧はＥ_γ（Ｅ_γ＞Ｅ_β）、図３の実線で示す充電率が略１００％の二次電池１の開放電圧はＥ_δ（Ｅ_δ＞Ｅ_γ）となり、そして、充電率が１００％の（満充電状態の）二次電池１の開放電圧は前記の満充電平衡電位Ｅ_ｅｑ（Ｅ_ｅｑ＞Ｅ_δ）となる。
【００５２】
二次電池１は充電率に応じた開放電圧を越えると、略印加電圧に比例して充電電流が増大していき、やがて、印加電圧を上昇させても充電電流は殆ど上昇しなくなり、充電電流は前記の電流ピーク値Ｉ_ｓｏに到達する。この充電電流が上昇しなくなったときの電流ピーク値Ｉ_ｓｏに対応する電圧値は前記所定の充電印加電圧値Ｅ_ｓとなり、該所定の充電印加電圧値Ｅ_ｓを越えると、二次電池１は、内部で活物質の酸化還元反応がさらに進んで、電気分解反応を惹き起こす不可逆化学反応領域Ｄに突入する。
【００５３】
この不可逆反応領域Ｄは図３の斜線で示す領域で、この不可逆化学反応領域Ｄでは、意図しない発熱反応や、膨潤等の異常により、ともすれば二次電池１の内部構造の破壊に繋がる恐れがある。また、そこまでには至らないにしても、不可逆反応が伸展し、二次電池１のサイクル寿命に大きな影響を与えてしまうため、この不可逆化学反応領域Ｄに達しないように充電制御することが必要となる。
【００５４】
ところで、二次電池１の蓄電容量は、充電電流と充電時間との積で求められる。これより充電時間を短くしようとすれば、充電電流を増やすことが必要である。
図３に示す充電率が略０％の二次電池１の端子電圧を、満充電平衡電位Ｅ_ｅｑに固定して充電すると、充電電流は充電率が上昇するに連れてＩ_ｅｑｏから減少していき、満充電状態では充電電流が０〔ｍＡ〕となるため、充電終了の判定が行いやすく、また、不可逆化学反応領域Ｄに達することもないため、二次電池１の内部構造に損傷を与える心配がない。
【００５５】
しかしながら、この満充電平衡電位Ｅ_ｅｑによる充電では、前記所定の充電印加電圧値Ｅ_ｓで充電する場合に比べて、充電電流が低く、充電時間が桁違いに長くなってしまう。
【００５６】
以上の充電特性から、本発明での充電は、充電電流のピーク値Ｉ_ｓｏ（または略ピーク値Ｉ_ｓｏ）を得る充電印加電圧値であって、満充電平衡電位を超えるが不可逆化学反応領域Ｄには達しない所定の充電印加電圧値Ｅ_ｓに固定して行い、満充電状態の判定は、前記の満充電平衡電位Ｅ_ｅｑに切り換えて行うことによって、二次電池１に損傷を与えることなく、急速充電を行うようにしている。
【００５７】
次に、二次電池１の充電装置の第１実施形態について説明する。
この二次電池１の充電装置の第１実施形態は、以下に示す二次電池１の充電装置の第２実施形態、及び第３実施形態の基本構成となる。
この第１実施形態の充電装置は、図１に示すように構成されており、プログラム・演算制御部４には、前記満充電平衡電位Ｅ_ｅｑで二次電池１を印加中に電流検出部３で検出されたチェック電流値ｉと、予め入力設定された充電完了基準値Ｊとを比較判定する判定手段であるチェック電流値判定プログラムとが組み込まれている。
【００５８】
そして、この第１実施形態の充電装置では、二次電池１を該所定の充電印加電圧値Ｅ_ｓで一定時間Ｔ_１印加して、大電流充電を行った後、印加電圧を該満充電平衡電位Ｅ_ｅｑに切り換え、この満充電平衡電位Ｅ_ｅｑで印加している間に、該満充電平衡電位Ｅ_ｅｑにおける電流値ｉを検出し、この検出した電流値ｉと予め設定した充電完了基準値Ｊとを比較することによって、該電流値ｉの方が該充電完了基準値Ｊよりも大きければ、再び前記所定の充電印加電圧値Ｅ_ｓでの充電を行い、該電流値ｉが該充電完了基準値Ｊ以下であれば、充電を停止するように制御している。
【００５９】
なお、この大電流充電は、前記所定の充電印加電圧値Ｅ_ｓに限らず、充電率が略０％の二次電池１に電圧を印加して、印加電圧を上昇させていったときに、該印加電圧に対する充電電流の増加率（ΔＩ／ΔＥ）が減少していき、充電電流が殆ど上昇しなくなったときの、不可逆化学反応領域Ｄ外における電流値に対応する充電印加電圧値で充電を行ってもよい。この充電印加電圧値による充電でも、電流ピーク値Ｉ_ｓｏ近くの電流が流れて、大電流充電を行うことができる。
【００６０】
次に、この第１実施形態の充電装置による二次電池１の充電制御を図４に示すフローチャートを参照しながら説明する。
まず、ユーザが充電する二次電池１の種類を操作部７からプログラム・演算制御部４に入力すると、該プログラム・演算制御部４中の記憶手段に予め記憶設定されたテーブルの中から、この二次電池１の種類に相当する所定の充電印加電圧値Ｅ_ｓと、満充電平衡電位Ｅ_ｅｑとがそれぞれ選択される（ステップＡ１）。
【００６１】
この所定の充電印加電圧値Ｅ_ｓと満充電平衡電位Ｅ_ｅｑとは、ニッケル−カドミウム二次電池、ニッケル−水素二次電池等の二次電池の種類や蓄電容量、型番等によって決まる固有の値であり、例えば、ニッケル−カドミウムニ次電池の場合、満充電平衡電位Ｅ_ｅｑは約１．４１〔Ｖ〕、所定の充電印加電圧値Ｅ_ｓはそれよりも高い約１．８０〔Ｖ〕として選択される。
【００６２】
次に、ユーザは操作部８を操作して充電開始操作を行うと（ステップＡ２）、二次電池１に所定の充電印加電圧値Ｅ_ｓが所定時間（一定時間）Ｔ_１継続して印加される（ステップＡ３）。
【００６３】
ここで、この印加時間Ｔ_１の設定に関しては、充電印加電圧値Ｅ_ｓを印加した場合における充電電流の時間変化から割出される。そして、この一定時間Ｔ_１経過後、今度は印加電圧を満充電平衡電位Ｅ_ｅｑに切り換える（ステップＡ４）。
【００６４】
そして、この満充電平衡電位Ｅ_ｅｑを微小時間Ｔ_２印加している間に、このとき二次電池１に流れている電流値ｉ（前記満充電平衡電位Ｅ_ｅｑにおける電流値ｉ）を検出する（ステップＡ５）。
【００６５】
次に、前記チェック電流値判定プログラムにより、この検出された電流値ｉと充電完了基準値Ｊとを比較して（ステップＡ６）、該電流値ｉが該充電完了基準値Ｊよりも大きければ、前記ステップＡ３に戻って、上述のフロー（充電制御）を繰り返し、一方、該電流値ｉが該充電完了基準値Ｊ以下であれば、二次電池１が満充電状態に達しているとして、ここで充電を停止する（ステップＡ７）。
【００６６】
ところで、前記の満充電平衡電位Ｅ_ｅｑを印加した場合、理論的には、図３のグラフに示すように、充電率１００％（満充電状態）で電流値ｉは０〔ｍＡ〕になるが、実際には電池によって極僅かながらバラツキが生じるため、これによる過充電を防止しようとすれば、前記充電完了基準値Ｊは０〔ｍＡ〕よりもやや大きな値、例えば、１０〔ｍＡ〕程度で設定するのが好ましい。
【００６７】
また、前記ステップＡ３での所定の充電印加電圧値Ｅ_ｓが印加される充電時間Ｔ_１は、二次電池１の容量、構造、形状等によって異なるが、例えば、ニッケル−カドミウム二次電池の場合は、約５５〔秒〕が選ばれる。また、前記満充電平衡電位Ｅ_ｅｑが印加される微小時間Ｔ_２としては約５〔秒〕が選ばれ、前記ステップＡ５での二次電池１に流れる電流の検出は、印加電圧を満充電平衡電位Ｅ_ｅｑに切り換えたときから、１［秒］以上経過した後に行われる。
【００６８】
この理由は、印加電圧を満充電平衡電位Ｅ_ｅｑに切り換えた直後には、二次電池１の電界面にはチャージした電荷が残っており、二次電池１への充電電流が安定せず、この状態で、二次電池１に流れる電流値を検出すると、正確に検出されない可能性が高く、従って、印加電圧を満充電平衡電位Ｅ_ｅｑに切り換えたときから、１［秒］以上待って、充電電流が安定した後に、二次電池１に流れる電流値を検出するようにしている。
【００６９】
なお、前記ステップＡ３での所定の充電印加電圧値Ｅ_ｓで、一定時間、印加した後であって、前記ステップＡ４の印加電圧を満充電平衡電位Ｅ_ｅｑに切り換える前に、二次電池１の両端子間を極小時間、例えば、約０．００１〔秒〕程、短絡するように構成してもよい。この構成の場合、二次電池１の両端子間の短絡によって二次電池１の電界面にチャージした電荷が除去されて、電界面がクリーンな状態となり、この短絡直後に二次電池１に流れる電流値が正確に検出できるようになり、この電流値の検出時に印加する満充電平衡電位Ｅ_ｅｑの印加時間Ｔ_２を約０．１〔秒〕程度とすることができる。
【００７０】
以上のように、第１実施形態の充電装置によれば、二次電池１の電流値ｉを検出することで、その充電状態を定期的にチェックするように構成したことによって、過度な化学反応（酸化還元反応）を引き起こすことなく、満充電状態まで適正に充電を行うことができる。
【００７１】
また、この充電方法によれば、二次電池１の内部構造に損傷を与えるのを防止することができるため、サイクル寿命を飛躍的に向上させることができる。さらに、この充電方法での主なる充電は、満充電平衡電位Ｅ_ｅｑ以上の所定の充電印加電圧値Ｅ_ｓで行われるため、かなり大きな充電電流が二次電池１に流されることとなり、これによって充電時間の短縮を図ることができる。
【００７２】
次に、二次電池１の充電装置の第２実施形態について説明する。
この第２実施形態の充電装置は、二次電池１の種類等を入力することなく、自動的に二次電池１の種類等が判別されて、急速に、満充電まで充電が行えるところに特徴がある。ここで言う、二次電池１の種類等とは、ニッケル−カドミウム二次電池とニッケル−水素二次電池などのように、正極、負極を構成する物質が異なる二次電池のみならず、正極、負極を構成する物質が同種で、蓄電容量が異なる二次電池も含むものとする。
【００７３】
二次電池１の満充電平衡電位Ｅ_ｅｑと、所定の充電印加電圧値Ｅ_ｓとは、二次電池の種類や容量などによって異なり、例えば、蓄電容量が１０００〔ｍＡｈ（ミリ・アンペア・アワー）〕のニッケル−カドミウム二次電池の満充電平衡電位は約１．４１〔Ｖ〕、所定の充電印加電圧値は約１．８０〔Ｖ〕となっており、蓄電容量が２０００〔ｍＡｈ〕のニッケル−水素二次電池の満充電平衡電位は約１．４４〔Ｖ〕、所定の充電印加電圧値は１．６０〔Ｖ〕となっている。
【００７４】
図５は、前記第１実施形態の二次電池１の充電装置において、満充電平衡電位を１．４４〔Ｖ〕、所定の充電印加電圧値を１．６０〔Ｖ〕として、ニッケル−水素二次電池対応の設定電圧値で、ニッケル−水素二次電池を充電したときの、電池端子電圧、充電電流、チェック電流の時間経過を示した図であり、図６は、同じく第１実施形態の二次電池１の充電装置において、満充電平衡電位を１．４４〔Ｖ〕、所定の充電印加電圧値を１．６０〔Ｖ〕として、ニッケル−水素二次電池対応の設定電圧値で、ニッケル−カドミウム二次電池を充電したときの、電池端子電圧、充電電流、チェック電流の時間経過を示した図である。図５及び図６において、前記ステップＡ３での所定の充電印加電圧値１．６０〔Ｖ〕を印加する一定時間Ｔ_１は５５秒とし、前記ステップＡ４における短絡は行わないものとして、前記ステップＡ５での満充電平衡電位１．４４〔Ｖ〕を印加する微小時間Ｔ_３は５秒とする。
【００７５】
また、図１に示す電源部２と電圧・電流制御部５と充電電圧供給部６との間には所定の抵抗があり、ニッケル−水素二次電池対応の設定では、電源部２から供給される２．０〔Ｖ〕の電圧は、該電源部２と該電圧・電流制御部５と該充電電圧供給部６との間で電圧降下が生じて、ニッケル−水素二次電池の端子間で、約１．６〔Ｖ〕の電圧が印加されるように設計されている。
【００７６】
また、ここで、図３に示すように、二次電池１を所定の充電印加電圧値Ｅ_ｓで印加しているときには、充電率に関わらず、二次電池１には一定の充電電流（電流ピーク値Ｉ_ｓｏ）が流れる。一方、二次電池１を所定の充電印加電圧値Ｅ_ｓよりも低い電圧値で印加しているときには、充電率が上昇するに連れて、二次電池１に流れる充電電流は減少していく。
【００７７】
このような特性から、図５に示すように、ニッケル−水素二次電池対応の設定電圧値で、ニッケル−水素二次電池を充電したときには、ニッケル−水素二次電池の端子間には、該ニッケル−水素二次電池の所定の充電印加電圧値（１．６０〔Ｖ〕）に相当する約１．６〔Ｖ〕の電圧が印加されて、該所定の充電印加電圧値に対応する所定の電流（電流ピーク値Ｉ_ｓｏ）が通電され、この結果、前記電源部２と電圧・電流制御部５と充電電圧供給部６との間での電圧降下値も略一定となる。すなわち、ニッケル−水素二次電池の端子間電圧は充電開始後から充電完了まで１．６〔Ｖ〕を越えることなく略一定となるとともに、充電電流も充電開始後から充電完了まで略一定となり、また、定期的に、ニッケル−水素二次電池の満充電平衡電位１．４４〔Ｖ〕によってチェック電流が適正にチェックされて、該ニッケル−水素二次電池を満充電まで急速、且つ適正に充電することができる。
【００７８】
一方、図６に示すように、ニッケル−水素二次電池対応の設定電圧値で、ニッケル−カドミウム二次電池を充電したときには、充電開始後からしばらくの間、該ニッケル−カドミウム二次電池の端子間には１．４〔Ｖ〕から１．６〔Ｖ〕の電圧で印加される。これは、ニッケル−カドミウム二次電池の所定の充電印加電圧値（１．８０〔Ｖ〕）よりも低い電圧値であり、この結果、充電率が上昇するに連れて、ニッケル−カドミウム二次電池に流れる充電電流は次第に減少していく。これに伴い、前記電源部２と電圧・電流制御部５と充電電圧供給部６との間での電圧降下値も徐々に減少していき、この結果、ニッケル−カドミウム二次電池の端子間に印加される電圧値が次第に上昇していき、やがて、１．６〔Ｖ〕を越えて、充電完了時では約１．８〔Ｖ〕となっている。
【００７９】
また、定期的に、ニッケル−水素二次電池の満充電平衡電位１．４４〔Ｖ〕によって、チェック電流をチェックしているが、このニッケル−水素二次電池の満充電平衡電位１．４４〔Ｖ〕はニッケル−カドミウム二次電池の満充電平衡電位１．４１〔Ｖ〕よりも高いために、ニッケル−カドミウム二次電池を正確に満充電まで充電することができない。
【００８０】
そこで、第２実施形態の充電装置では、ニッケル−水素二次電池と、ニッケル−カドミウム二次電池とを判別する場合を例に挙げて説明すると、二次電池１を、ニッケル−水素二次電池対応の電圧値で、充電と、充電状態のチェックをし、この充電過程で、該二次電池１の端子電圧が１．６〔Ｖ〕を越えたときには、該二次電池１はニッケル−カドミウム二次電池であると判断して、その後は、該二次電池１を、ニッケル−カドミウム二次電池対応の電圧値で、充電と、充電状態のチェックを行う。
【００８１】
以下、具体的に説明すると、この第２実施形態の充電装置も、図１に示すように構成されており、プログラム・演算制御部４の記憶手段（メモリ）には、複数の二次電池についての、満充電平衡電位Ｅ_ｅｑと、所定の充電印加電圧値Ｅ_ｓとが記憶されている。また、プログラム・演算制御部４には、二次電池１を満充電平衡電位Ｅ_ｅｑで印加中に電流検出部３で検出されたチェック電流値ｉと、予め入力設定された充電完了基準値Ｊとを比較判定する判定手段であるチェック電流値判定プログラムと、二次電池１を所定の充電印加電圧値Ｅ_ｓで充電中に電圧検出部９で検出された充電電圧値ｅと、該所定の充電印加電圧値Ｅ_ｓとを比較判定する判定手段である充電電圧値判定プログラムと、が組み込まれている。
なお、この第２実施形態の充電装置におけるその他の構成は、前記第１実施形態の充電装置と略同様であるため、その説明を省略する。
【００８２】
まず始めに、簡単のために、プログラム・演算制御部４の記憶手段に、２種類の二次電池についての、満充電平衡電位Ｅ_ｅｑ（Ｅ_ｅｑｌ・Ｅ_ｅｑｈ）と、所定の充電印加電圧値Ｅ_ｓ（Ｅ_ｓｌ・Ｅ_ｓｈ）とが記憶されている充電装置による二次電池１の充電制御を、図７に示すフローチャートを参照しながら説明する。
ここで、満充電平衡電位については、Ｅ_ｅｑｌ＜Ｅ_ｅｑｈとし、所定の充電印加電圧値については、Ｅ_ｓｌ＜Ｅ_ｓｈとする。
【００８３】
まず、ユーザは操作部８を操作して充電開始操作を行うと（ステップＢ１）、充電装置にセットされた二次電池１に２種類の二次電池の所定の充電印加電圧値のうちの低い方の所定の充電印加電圧値Ｅ_ｓｌで所定時間（一定時間）Ｔ_１継続して印加される（ステップＢ２）。
【００８４】
そして、二次電池１を該低い方の所定の充電印加電圧値Ｅ_ｓｌで一定時間Ｔ_１充電している間に、前記電圧検出部９によって二次電池１に印加されている電圧値ｅを検出し（ステップＢ３）、前記充電電圧値判定プログラムによりこの検出した電圧値ｅの判定を行い（ステップＢ４）、該電圧値ｅが該低い方の所定の充電印加電圧値Ｅ_ｓｌよりも大きな値であれば、後記のステップＢ１０へジャンプし、該電圧値ｅが該低い方の所定の充電印加電圧値Ｅ_ｓｌ以下であれば、次のステップＢ５へ移行する。
【００８５】
前記一定時間Ｔ_１時間経過後に、今度は、二次電池１の印加電圧を２種類の二次電池の満充電平衡電位のうちの低い方の満充電平衡電位Ｅ_ｅｑｌに切り換えて、二次電池１を該低い方の満充電平衡電位Ｅ_ｅｑｌで微小時間Ｔ_２印加する（ステップＢ５）。
【００８６】
次に、二次電池１をこの低い方の満充電平衡電位Ｅ_ｅｑｌで微小時間Ｔ_２印加している間に、前記電流検出部３によって二次電池１に流れている電流値ｉを検出する（ステップＢ６）。
そして、前記チェック電流値判定プログラムによってこの検出した電流値ｉの判定を行い（ステップＢ７）、該電流値ｉが充電完了基準値Ｊより大きな値であれば、前記ステップＢ２に戻って上記のフローを繰り返し、一方、該電流値ｉが該充電完了基準値Ｊ以下であれば、充電を停止する（ステップＢ８）。
【００８７】
一方、前記ステップＢ４において、二次電池１を低い方の所定の充電印加電圧値Ｅ_ｓｌで一定時間Ｔ_１充電している間に、電圧検出部９により検出した電圧値ｅが該低い方の所定の充電印加電圧値Ｅ_ｓｌよりも大きな値であれば、二次電池１の印加電圧を２種類の二次電池の所定の充電印加電圧値のうちの高い方の所定の充電印加電圧値Ｅ_ｓｈに切り換え、該高い方の所定の充電印加電圧値Ｅ_ｓｈで一定時間Ｔ_１継続して印加する（ステップＢ９）。
【００８８】
前記一定時間Ｔ_１時間経過後に、今度は、二次電池１の印加電圧を２種類の二次電池の満充電平衡電位のうちの高い方の満充電平衡電位Ｅ_ｅｑｈに切り換えて、二次電池１を該高い方の満充電平衡電位Ｅ_ｅｑｈで微小時間Ｔ_３印加する（ステップＢ１０）。
【００８９】
次に、二次電池１をこの高い方の満充電平衡電位Ｅ_ｅｑｈで微小時間Ｔ_３印加している間に、前記電流検出部３によって二次電池１に流れている電流値ｉを検出する（ステップＢ１１）。
そして、前記チェック電流値判定プログラムによってこの検出した電流値ｉの判定を行い（ステップＢ１２）、該電流値ｉが充電完了基準値Ｊより大きな値であれば、前記ステップＢ９に戻って上記のフローを繰り返し、一方、該電流値ｉが該充電完了基準値Ｊ以下であれば、充電を停止する（ステップＢ９）。
【００９０】
以上、プログラム・演算制御部４の記憶手段に、２種類の二次電池についての、満充電平衡電位Ｅ_ｅｑｌ・Ｅ_ｅｑｈと、所定の充電印加電圧値Ｅ_ｓｌ・Ｅ_ｓｈとが記憶されている充電装置による二次電池１の充電制御の説明である。
【００９１】
次に一般に、プログラム・演算制御部４の記憶手段に、ｎ（ｎは２以上の自然数）種類の二次電池についての、満充電平衡電位Ｅ_ｅｑ（Ｅ_ｅｑ１、Ｅ_ｅｑ２、・・・、Ｅ_ｅｑｎ）、所定の充電印加電圧値Ｅ_ｓ（Ｅ_ｓ１、Ｅ_ｓ２、・・・、Ｅ_ｓｎ）とが記憶されている充電装置による二次電池１の充電制御について図８に示すフローチャートを参照しながら説明する。
ここで、満充電平衡電位は、Ｅ_ｅｑ１＜Ｅ_ｅｑ２、・・・、＜Ｅ_ｅｑｎとし、所定の充電印加電圧値は、Ｅ_ｓ１＜Ｅ_ｓ２、・・・、＜Ｅ_ｓｎとする。
【００９２】
まず、ここで、変数をｋ（ｋ＝１、２、・・・、ｎ）として、該ｋを初期化し、ｋ＝１とする（ステップＣ１）。次に、ユーザが操作部８を操作して充電開始操作を行うと（ステップＣ２）、充電装置にセットされた二次電池１にｎ種類の二次電池の所定の充電印加電圧値のうち第ｋ番目に低い所定の充電印加電圧値Ｅ_ｓｋで所定時間（一定時間）Ｔ_１継続して印加される（ステップＣ３）。
【００９３】
ここで、ｋ＝ｎのときは（ステップＣ４）、後記のステップＣ８へジャンプし、ｋ≦ｎ−１のときは、二次電池１を該第ｋ番目に低い所定の充電印加電圧値Ｅ_ｓｋで一定時間Ｔ_１充電している間に、前記電圧検出部９によって二次電池１に印加されている電圧値ｅを検出し（ステップＣ５）、前記充電電圧値判定プログラムによりこの検出した電圧値ｅの判定を行い（ステップＣ６）、該電圧値ｅが該第ｋ番目に低い所定の充電印加電圧値Ｅ_ｓｋよりも大きな値で検出されていれば、該ｋに１を加えたものを新たなｋとして（ステップＣ７）、前記ステップＣ３に戻り、該電圧値ｅが該第ｋ番目に低い所定の充電印加電圧値Ｅ_ｓｋ以下で検出されていれば、ステップＣ８へ移行する。
【００９４】
前記一定時間Ｔ_１経過後に、今度は、二次電池１の印加電圧をｎ種類の二次電池の満充電平衡電位のうち第ｋ番目に低い満充電平衡電位Ｅ_ｅｑｋに切り換え、二次電池１を該第ｋ番目に低い満充電平衡電位Ｅ_ｅｑｋで微小時間Ｔ_２印加する（ステップＣ８）。
【００９５】
次に、二次電池１を該第ｋ番目に低い満充電平衡電位Ｅ_ｅｑｋで微小時間Ｔ_２印加している間に、前記電流検出部３によって二次電池１に流れている電流値ｉを検出する（ステップＣ９）。
【００９６】
そして、前記チェック電流値判定プログラムによってこの検出した電流値ｉの判定を行い（ステップＣ１０）、該電流値ｉが充電完了基準値Ｊより大きな値であれば、前記ステップＣ３に戻って上記のフローを繰り返し、一方、該電流値ｉが該充電完了基準値Ｊ以下であれば、充電を停止する（ステップＣ１１）。
【００９７】
なお、前記ステップＢ２（又はステップＢ９、ステップＣ３）での所定の充電印加電圧値で、一定時間、印加した後であって、前記ステップＢ５（又はステップＢ１０、ステップＣ８）の印加電圧を満充電平衡電位に切り換える前に、二次電池１の両端子間を極小時間、例えば、約０．００１〔秒〕程、短絡するように構成してもよい。この構成の場合、二次電池１の両端子間の短絡によって二次電池１の電界面にチャージした電荷が除去されて、電界面がクリーンな状態となり、この短絡直後に二次電池１に流れる電流値が正確に検出できるようになり、この電流値の検出時に印加する満充電平衡電位Ｅ_ｅｑの印加時間Ｔ_２を約０．１〔秒〕程度とすることができる。
【００９８】
以上のように、第２実施形態の充電装置によれば、前記第１実施形態の充電装置と同様の効果を奏するとともに、充電過程で、二次電池１の種類等を自動的に判別して、過度な化学反応（酸化還元反応）を引き起こすことなく、急速、且つ適正に満充電まで充電を行うことができる。
【００９９】
次に、二次電池１の充電装置の第３実施形態について説明する。
この第３実施形態の充電装置は、所定の充電印加電圧値Ｅ_ｓでの充電中に電圧検出部９で検出された充電電圧値ｅと、その前の回の所定の充電印加電圧値Ｅ_ｓでの充電中に電圧検出部９で検出された充電電圧値ｅとの差Δｅが、予め入力設定された所定の範囲Ｗ内にあるかを判定して、該所定の範囲Ｗを越えていれば、他の種別の二次電池１に対応する満充電平衡電位Ｅ_ｅｑと所定の充電印加電圧値Ｅ_ｓとに切り換えて充電するように構成した点が、第２実施形態の充電装置と異なる点である。
【０１００】
この第３実施形態の充電装置も、図１に示すように構成されており、プログラム・演算制御部４の記憶手段（メモリ）には、複数の二次電池についての、満充電平衡電位Ｅ_ｅｑと、所定の充電印加電圧値Ｅ_ｓとが記憶されている。また、プログラム・演算制御部４には、二次電池１を満充電平衡電位Ｅ_ｅｑで印加中に電流検出部３で検出されたチェック電流値ｉと、予め入力設定された充電完了基準値Ｊとを比較判定する判定手段であるチェック電流値判定プログラムと、前記所定の充電印加電圧値Ｅ_ｓでの充電中に電圧検出部９で検出された充電電圧値ｅと、その前の回の所定の充電印加電圧値Ｅ_ｓでの充電中に電圧検出部９で検出された充電電圧値ｅとの差Δｅが、予め入力設定された所定の範囲Ｗ内にあるかを判定する判定手段である電圧差判定プログラムと、が組み込まれている。
なお、この第３実施形態の充電装置におけるその他の構成は、前記第１実施形態の充電装置と略同様であるため、その説明を省略する。
【０１０１】
まず始めに、簡単のために、プログラム・演算制御部４の記憶手段に、２種類の二次電池についての、満充電平衡電位Ｅ_ｅｑ（Ｅ_ｅｑｌ・Ｅ_ｅｑｈ）と、所定の充電印加電圧値Ｅ_ｓ（Ｅ_ｓｌ・Ｅ_ｓｈ）とが記憶されている充電装置による二次電池１の充電制御を図９に示すフローチャートを参照しながら説明する。
ここで、満充電平衡電位については、Ｅ_ｅｑｌ＜Ｅ_ｅｑｈとし、所定の充電印加電圧値については、Ｅ_ｓｌ＜Ｅ_ｓｈとする。
【０１０２】
まず、ユーザは操作部８を操作して充電開始操作を行うと（ステップＤ１）、充電装置にセットされた二次電池１に２種類の二次電池の所定の充電印加電圧値のうちの低い方の所定の充電印加電圧値Ｅ_ｓｌで所定時間（一定時間）Ｔ_１継続して印加される（ステップＤ２）。
【０１０３】
そして、二次電池１を該低い方の所定の充電印加電圧値Ｅ_ｓｌで一定時間Ｔ_１充電している間に、前記電圧検出部９によって二次電池１に印加されている電圧値ｅを検出して（ステップＤ３）、前記電圧差判定プログラムによって今回該低い方の所定の充電印加電圧値Ｅ_ｓｌで充電している間に検出した電圧値ｅと、前回該低い方の所定の充電印加電圧値Ｅ_ｓｌで充電している間に検出した電圧値ｅとの差Δｅが所定の範囲Ｗ内にあるかの判定を行い（ステップＤ４）、該差Δｅが該所定の範囲Ｗ内にあれば、次のステップＤ５へ移行し、該差Δｅが該所定の所定の範囲Ｗを越えていれば、後記のステップＤ１０へジャンプする。ただし、今回の電圧値ｅの検出が第１回目のときは、そのまま次のステップＤ５へ移行する。
【０１０４】
前記一定時間Ｔ_１時間経過後に、今度は、二次電池１の印加電圧を２種類の二次電池の満充電平衡電位のうちの低い方の満充電平衡電位Ｅ_ｅｑｌに切り換えて、二次電池１を該低い方の満充電平衡電位Ｅ_ｅｑｌで微小時間Ｔ_２印加する（ステップＤ５）。
【０１０５】
次に、二次電池１をこの低い方の満充電平衡電位Ｅ_ｅｑｌで微小時間Ｔ_２印加している間に、前記電流検出部３によって二次電池１に流れている電流値ｉを検出する（ステップＤ６）。
そして、前記チェック電流値判定プログラムによってこの検出した電流値ｉの判定を行い（ステップＤ７）、該電流値ｉが充電完了基準値Ｊより大きな値であれば、前記ステップＤ２に戻って上記のフローを繰り返し、一方、該電流値ｉが該充電完了基準値Ｊ以下であれば、充電を停止する（ステップＤ８）。
【０１０６】
一方、前記ステップＤ４において、前記の差Δｅが前記所定の範囲Ｗを越えていれば、二次電池１の印加電圧を２種類の二次電池の所定の充電印加電圧値のうちの高い方の所定の充電印加電圧値Ｅ_ｓｈに切り換え、該高い方の所定の充電印加電圧値Ｅ_ｓｈで所定時間（一定時間）Ｔ_１継続して印加する（ステップＤ９）。
【０１０７】
前記一定時間Ｔ_１時間経過後に、今度は、二次電池１の印加電圧を２種類の二次電池の満充電平衡電位のうちの高い方の満充電平衡電位Ｅ_ｅｑｈに切り換えて、二次電池１を該高い方の満充電平衡電位Ｅ_ｅｑｈで微小時間Ｔ_２印加する（ステップＤ１０）。
【０１０８】
次に、二次電池１をこの高い方の満充電平衡電位Ｅ_ｅｑｈで微小時間Ｔ_２印加している間に、前記電流検出部３によって二次電池１に流れている電流値ｉを検出する（ステップＤ１１）。
【０１０９】
そして、前記チェック電流値判定プログラムによってこの検出した電流値ｉの判定を行い（ステップＤ１２）、該電流値ｉが充電完了基準値Ｊより大きな値であれば、前記ステップＤ９に戻って上記のフローを繰り返し、一方、該電流値ｉが該充電完了基準値Ｊ以下であれば、充電を停止する（ステップＤ８）。
【０１１０】
以上、プログラム・演算制御部４の記憶手段に、２種類の二次電池についての、満充電平衡電位Ｅ_ｅｑｌ・Ｅ_ｅｑｈと、所定の充電印加電圧値Ｅ_ｓｌ・Ｅ_ｓｈとが記憶されている充電装置による二次電池１の充電制御の説明である。
次に一般に、プログラム・演算制御部４の記憶手段に、ｎ（ｎは２以上の自然数）種類の二次電池についての、満充電平衡電位Ｅ_ｅｑ（Ｅ_ｅｑ１、Ｅ_ｅｑ２、・・・、Ｅ_ｅｑｎ）、所定の充電印加電圧値Ｅ_ｓ（Ｅ_ｓ１、Ｅ_ｓ２、・・・、Ｅ_ｓｎ）とが記憶されている充電装置による二次電池１の充電制御について図１０に示すフローチャートを参照しながら説明する。
ここで、満充電平衡電位は、Ｅ_ｅｑ１＜Ｅ_ｅｑ２、・・・、＜Ｅ_ｅｑｎとし、所定の充電印加電圧値は、Ｅ_ｓ１＜Ｅ_ｓ２、・・・、＜Ｅ_ｓｎとする。
【０１１１】
まず、ここで、変数をｋ（ｋ＝１、２、・・・、ｎ）として、該ｋを初期化し、ｋ＝１とする（ステップＦ１）。次に、ユーザが操作部８を操作して充電開始操作を行うと（ステップＦ２）、充電装置にセットされた二次電池１にｎ種類の二次電池の所定の充電印加電圧値のうち第ｋ番目に低い所定の充電印加電圧値Ｅ_ｓｋで所定時間（一定時間）Ｔ_１継続して印加される（ステップＦ３）。
【０１１２】
ここで、ｋ＝ｎのときは（ステップＦ４）、後記のステップＦ８へジャンプし、ｋ≦ｎ−１のときは、二次電池１を該第ｋ番目に低い所定の充電印加電圧値Ｅ_ｓｋで一定時間Ｔ_１充電している間に、前記電圧検出部９によって二次電池１に印加されている電圧値ｅを検出して（ステップＦ５）、前記電圧差判定プログラムにより今回該第ｋ番目に低い所定の充電印加電圧値Ｅ_ｓｋで充電している間に検出した電圧値ｅと、前回該第ｋ番目に低い所定の充電印加電圧値Ｅ_ｓｋで充電している間に検出した電圧値ｅとの差Δｅが所定の範囲Ｗ内にあるかの判定を行い（ステップＦ６）、該差Δｅが該所定の範囲Ｗ内にあれば、ステップＦ８へ移行し、該差Δｅが該所定の所定の範囲Ｗを越えていれば、該ｋに１を加えたものを新たなｋとして（ステップＦ７）、前記ステップＦ３へ戻る。ただし、今回の電圧値ｅの検出が第１回目のときは、ステップＦ８へ移行する。
【０１１３】
前記一定時間Ｔ_１経過後に、今度は、二次電池１の印加電圧をｎ種類の二次電池の満充電平衡電位のうち第ｋ番目に低い満充電平衡電位Ｅ_ｅｑｋに切り換え、二次電池１を該第ｋ番目に低い満充電平衡電位Ｅ_ｅｑｋで微小時間Ｔ_２印加する（ステップＦ８）。
【０１１４】
次に、二次電池１を該第ｋ番目に低い満充電平衡電位Ｅ_ｅｑｋで微小時間Ｔ_２印加している間に、前記電流検出部３によって二次電池１に流れている電流値ｉを検出する（ステップＦ９）。
【０１１５】
そして、前記チェック電流値判定プログラムによってこの検出した電流値ｉの判定を行い（ステップＦ１０）、該電流値ｉが充電完了基準値Ｊより大きな値であれば、前記ステップＦ３に戻って上記のフローを繰り返し、一方、該電流値ｉが該充電完了基準値Ｊ以下であれば、充電を停止する（ステップＦ１１）。
【０１１６】
なお、前記ステップＤ２（又はステップＤ９、ステップＦ３）での所定の充電印加電圧値で、一定時間、印加した後であって、前記ステップＤ５（又はステップＤ１０、ステップＦ８）の印加電圧を満充電平衡電位に切り換える前に、二次電池１の両端子間を極小時間、例えば、約０．００１〔秒〕程、短絡するように構成してもよい。この構成の場合、二次電池１の両端子間の短絡によって二次電池１の電界面にチャージした電荷が除去されて、電界面がクリーンな状態となり、この短絡直後に二次電池１に流れる電流値が正確に検出できるようになり、この電流値の検出時に印加する満充電平衡電位Ｅ_ｅｑの印加時間Ｔ_２を約０．１〔秒〕程度とすることができる。
【０１１７】
以上のように、第３実施形態の充電装置によっても、前記第１実施形態の充電装置と同様の効果を奏するとともに、充電過程で、二次電池１の種類等を自動的に判別して、過度な化学反応（酸化還元反応）を引き起こすことなく、急速、且つ適正に満充電まで充電を行うことができる。
【０１１８】
次に、二次電池１の充電装置の第４実施形態について説明する。
二次電池１は充電完了後、放置しておくと、自己放電して、電池電圧が次第に低下していき、例えば、２日放置しておくと、電池電圧は約１５％低下してしまい、３０日放置しておくと、電池電圧は約４０％も低下してしまう。このため、二次電池１をデジタルカメラなどの機器に使用する場合に、その電池電圧が低くすぎて、役に立たない場合がある。
【０１１９】
そこで、この第４実施形態の充電装置では、前記第１実施形態から第１２実施形態のうちの何れか１つの実施形態で、若しくは、上記実施形態以外の方法で、充電を完了した二次電池１の電池電圧値が所定の電圧値以下となったときに、再充電を行うように構成している。
【０１２０】
この第４実施形態の充電装置も、図１に示すように構成されており、プログラム・演算制御部４には、電圧検出部９によって検出された充電完了後の二次電池１の電池電圧値と、前記満充電平衡電位Ｅ_ｅｑよりも低い再充電電圧値Ｅ_ｒとを比較判定する判定手段としての再充電判定プログラムが組み込まれている。
【０１２１】
この再充電電圧値Ｅ_ｒは、例えば、満充電平衡電位Ｅ_ｅｑの８０％と設定されており、充電完了後においても、充電装置にセットされた二次電池１の電池電圧は電圧検出部９によって監視されており、該二次電池１の電池電圧値が再充電電圧値Ｅ_ｒ以下となったときに、プログラム・演算制御部４から再充電指令が出力され、前記充電電圧供給部６から充電電圧が供給されて、該二次電池１の再充電を行うように構成している。
【０１２２】
なお、この再充電の停止は、前記第１実施形態から第３実施形態のうちの何れか１つの実施形態の充電停止条件、若しくは、上記実施形態以外の方法の充電装置にあっては、その充電装置の充電停止条件に従うものとする。
【０１２３】
以上のように、再充電を行うように構成すれば、充電装置から取り出した二次電池１の電池電圧は、いつでも再充電電圧値Ｅ_ｒ以上で、使用に適した状態にあり、利便性の向上を図ることができる。
また、この再充電においても、過度な化学反応（酸化還元反応）を引き起こすことなく、満充電状態まで適正に再充電を行うため、二次電池１の内部構造に損傷を与えず、サイクル寿命を飛躍的に向上させることができるとともに、満充電までの充電時間も短くなる。
【０１２４】
次に、二次電池１・１・・・の充電装置の第５実施形態について説明する。
図１１は二次電池１・１・・・の充電装置の第５実施形態の充電装置の構成を示す平面図であり、この第５実施形態に係る充電装置５０は、複数の二次電池１・１・・・（本実施の形態では、４本の二次電池１・１・・・）の充電を行うものである。
【０１２５】
図１１において、符号５０ａは二次電池１をセットするための座部であり、符号５０ｂは外気取込口ある。符号５１は第１表示部で、座部５０ａにセットされた二次電池１が満充電状態に近いときに点灯し、例えば、二次電池１の電池電圧が前記の再充電電圧値Ｅ_ｒに達したときに、点灯するように構成されている。この設定の場合、一旦充電を終えて点灯している第１表示部５１が消灯に切り換わったときに、前記再充電が実行されるように構成される。符号５２は第２表示部で、図１１中の太線矢印の順番に交互に充電が行われる二次電池１・１・・・のうち現在充電中の二次電池１に対応する第２表示部５２が点滅し、二次電池１が満充電状態に達して充電が完了すると、その二次電池１に対応する第２表示部５２が点灯するように構成されている。符号５３は二次電池１の座部５０ａにセットされた二次電池１を取り出すための取出ボタン、符号５４は二次電池１・１・・・の充電を開始させるためのスタートボタン、符号５５は電源ランプであり、該充電装置５０は図示せぬ電源コードを介して商用電源に接続されるようになっている。
【０１２６】
この第５実施形態の充電装置５０は、二次電池１の充電状態をチェックした後、所定の電圧で所定時間充電する一連の充電動作を各未充電の二次電池１ごとに図１１中の太線矢印の順番に交互に行い、これを１ターンとして、該ターンを繰り返しながら複数の二次電池１・１・・・を充電し、前記充電状態のチェックで満充電状態に達したと判断された二次電池１から充電を停止するように構成している。
なお、満充電状態に達した二次電池１は、次のターンでその順番が飛ばされる（スキップする）ものとする。また、各ターンで二次電池１を充電する順番は、図１１中の太線矢印の順番に限定するものではなく、他の順番で行ってもよい。
【０１２７】
前記充電状態のチェックは、例えば、前記第１実施形態におけるステップＡ６での充電電流値ｉの判定、若しくは、前記第２実施形態におけるステップＢ７、ステップＢ１２又はステップＣ１０での充電電流値ｉの判定、若しくは、前記第３実施形態におけるステップＤ７、ステップＤ１２又はステップＦ１０での充電電流値ｉの判定等により行われ、前記充電電圧には、例えば、前記の所定の充電印加電圧値Ｅ_ｓが用いられる。
【０１２８】
以上のように充電装置５０が構成され、この充電装置５０では、各二次電池１における先のターンの一連の充電動作の完了から、次のターンの一連の充電動作の開始までの間、充電が休止され、この休止期間が緩和時間となり、電極表面が安定して、次のターンでの満充電状態のチェックを精確に行うことができ、信頼性が向上する。
【０１２９】
補足すると、二次電池１の充電中、電解液と接する電極の表面で電極反応が起こり、この電極反応の過程は、電解液内部から電極表面への反応物の移動と、反応物と電極の間での電子の移動と、電極表面から電解液内部への生成物の移動との同時過程であり、この移動にはかなりの時間を要することから、二次電池１の充電休止直後に、満充電状態をチェックすると、電極表面付近で電気泳動している移動過程のイオン等のために、あたかも、満充電状態に達したかのように検知されてしまうことがある。この誤検知を防ぐためにも、緩和時間を設けることは有効であり、この第５実施形態の充電装置５０では、各二次電池１・１・・・ごとの充電サイクルの一環として、合理的、且つ効果的に緩和時間が設けられている。
【０１３０】
なお、前記第１実施形態から第３実施形態においても、個々の二次電池１において、一定時間Ｔ_１の充電と、その後の充電状態のチェックとの間に、緩和時間を設けるように構成してもよい。
【０１３１】
次に、二次電池１の充電装置の第６実施形態を説明する。
図１２に示すように、この第６実施形態の充電装置５０の内部には、冷却手段として冷却ファン６１が設けられている。この第６実施形態の充電装置５０による二次電池１の充電は、前記第１実施形態から第５実施形態のうちの何れかの実施形態に示すように行われ、従って、二次電池１の内部では過度の化学反応が起こることなく、二次電池１自体は発熱はしない。しかしながら、充電を制御する電子部品の抵抗等が発熱するために、該抵抗等の発熱素子６４・６５を冷却すべく冷却ファン６１が設けられている。
図１２において、符号５０Ｃは充電装置５０の筐体であるケーシング、符号５０ｂはケーシング５０Ｃ表面の一側部に設けられた外気取込口（図１１参照）、符号５０ｄはケーシング５０Ｃ裏面の一側部に設けられた外気取込口、符号５０ｅはケーシング５０Ｃ裏面の他側部に設けられた排気口、符号５０ｈはケーシング５０Ｃを支持する脚部である。符号６２及び符号６３は基板であり、符号６４及び符号６５は抵抗等の発熱素子ある。
【０１３２】
以上のように充電装置５０は構成されており、冷却ファン６１を作動することで、外気取込口５０ｂ・５０ｄからケーシング５０Ｃ周囲の外気が取り込まれ、該外気は発熱素子６４・６５の表面に沿うように流れて、この結果、該発熱素子６４・６５が冷却されるようになっている。そうして、取り込まれた外気は冷却ファン６１によりさらに奥に引き込まれて、排気口５０ｅから排気される。
【０１３３】
以上のような構成で、発熱素子６４・６５の発熱が抑えられて、二次電池１への熱伝達が防がれ、二次電池１の内部での過度な化学反応（酸化還元反応）を助長することもなく、また、ユーザが二次電池１があたかも発熱したかのように錯覚にとらわれることもない。この結果、二次電池１は満充電状態まで適正に充電が行われて、二次電池１の内部構造に損傷を与えるのを防止することができ、サイクル寿命を飛躍的に向上させることができる。
【０１３４】
次に、二次電池１の充電装置の第７実施形態を説明する。
この第７実施形態の充電装置５０は、該充電装置５０にセットされた二次電池１をワンタッチで取り出すための取出手段が設けられている。
【０１３５】
図１１及び図１３に示すように、この第７実施形態の充電装置５０の取出手段は、ユーザが押し下げ操作する取出ボタン５３と、充電装置５０の座部５０ａにセットされた二次電池１を押し上げる押上部材５７と、該押上部材５７を軸支する回動支点軸５８と、該回動支点軸５８に取り付けられて該押上部材５７を反押上方向へ付勢するトーションスプリング５９と、を備えている。
【０１３６】
以上のような構成で、図１３（ｂ）に示すように、ユーザが操作部材である取出ボタン５３を押すと、該取出ボタン５３の下端が押上部材５７の他側部を押し下げ、回動支点軸５８を支点にして、該押上部材５７の一側部が座部５０ａから上昇し、これにより、二次電池１が押し上げられて、該二次電池１の両端子の支持が外れるようになっている。
【０１３７】
そして、図１３（ａ）に示すように、ユーザが押していた取出ボタン５３をはなすと、付勢手段であるトーションスプリング５９の復元力によって、押上部材５７の一側部は元位置の座部５０ａの凹曲面に沿った位置に復帰し、二次電池１のセットが可能な状態となる。
【０１３８】
以上のように、ユーザが取出ボタン５３を操作することで、充電装置５０の座部５０ａから押上部材５７の一側部が出没し、二次電池１が取り出されるようになっている。このような構成で、二次電池１をワンタッチで簡単に取り出すことができ、利便性が向上する。
【０１３９】
次に、二次電池１の充電装置の第８実施形態を説明する。
この第８実施形態の充電装置５０は、前記第７実施形態の取出手段とは、別形態の取出手段が設けられている。
【０１４０】
図１４に示すように、この第８実施形態の充電装置５０の取出手段は、充電装置５０の座部５０ａの長手方向一側部を陥没させた構成で、この陥没部５０ｋでは、セットされた二次電池１の一側部（長手方向一側部）が宙に浮いた状態となっている。
【０１４１】
図１４（ａ）（ｂ）に示すように、二次電池１の一側部を押し下げると、該一側部が陥没部５０ｋに沈み込み、二次電池１の他側部が浮き上がって、該二次電池１の両端子の支持が外れ、二次電池１が取り出されるようになっている。このような構成で、二次電池１をワンタッチで簡単に取り出すことができ、利便性が向上する。
【０１４２】
以上に二次電池１の充電装置の第１実施形態から第８実施形態について説明をしたが、前記実施の形態に限定されるものではなく、請求項に記載の範囲内で種々変更して実施することが可能である。
【０１４３】
【発明の効果】
以上のように構成した本発明は、次のような効果を奏する。
まず、請求項１に記載の発明では、充電過程で、二次電池の種類等を自動的に判別して、二次電池の内部で過度な化学反応（酸化還元反応）を引き起こすことなく、満充電状態まで適正に充電が行うことができる。また、この結果、二次電池の内部構造を傷めず、サイクル寿命を飛躍的に向上させることができる。特に、この充電装置での主なる充電は、満充電平衡電位以上の所定の充電印加電圧値で行うため、かなり大きな充電電流が流れて、充電時間の短縮を図ることができる。また、充電状態のチェックは、満充電平衡電位で行うため、精確に満充電状態まで充電することができる。
【０１４４】
また、請求項２に記載の発明でも、充電過程で、二次電池の種類等を自動的に判別して、二次電池の内部で過度な化学反応（酸化還元反応）を引き起こすことなく、満充電状態まで適正に充電が行うことができる。また、この結果、二次電池の内部構造を傷めず、サイクル寿命を飛躍的に向上させることができる。特に、この充電装置での主なる充電は、満充電平衡電位以上の所定の充電印加電圧値で行うため、かなり大きな充電電流が流れて、充電時間の短縮を図ることができる。また、充電状態のチェックは、満充電平衡電位で行うため、精確に満充電状態まで充電することができる。
【０１４５】
そして、請求項３に記載の発明では、充電装置から取り出した二次電池の電池電圧は、いつでも再充電電圧値以上で、使用に適した状態にあり、利便性の向上を図ることができる。
また、この再充電においても、過度な化学反応（酸化還元反応）を引き起こすことなく、満充電状態まで適正に再充電を行うため、二次電池の内部構造に損傷を与えず、サイクル寿命を飛躍的に向上させることができるとともに、満充電までの充電時間も短くなる。
【０１４６】
また、請求項４に記載の発明では、二次電池の充電状態をチェックして、所定の充電電圧で所定時間充電する一連の充電動作を繰り返し、前記充電状態のチェックで満充電状態に達したと判断されると充電を停止するように構成した二次電池の充電装置において、前記一連の充電動作間に、緩和時間を設けたことで、次の一連の充電動作での満充電状態のチェックを精確に行うことができ、信頼性が向上する。
【０１４７】
そして、請求項５に記載の発明では、各二次電池における先のターンの一連の充電動作の完了から、次のターンの一連の充電動作の開始までの間、充電が休止され、この休止期間が緩和時間となり、電極表面が安定して、次のターンでの満充電状態のチェックを精確に行うことができ、信頼性が向上する。
補足すると、二次電池の充電中、電解液と接する電極の表面で電極反応が起こり、この電極反応の過程は、電解液内部から電極表面への反応物の移動と、反応物と電極の間での電子の移動と、電極表面から電解液内部への生成物の移動との同時過程であり、この移動にはかなりの時間を要することから、二次電池の充電休止直後に、満充電状態をチェックすると、電極表面付近で電気泳動している移動過程のイオン等のために、あたかも、満充電状態に達したかのように検知されてしまうことがある。この誤検知を防ぐためにも、緩和時間を設けることは有効であり、このこの第３０発明の二次電池の充電装置では、各二次電池ごとの充電サイクルの一環として、合理的、且つ効果的に緩和時間が設けられている。
【０１４８】
さらに、請求項６に記載の発明では、請求項１から請求項５のうち何れか一項に記載の二次電池の充電装置において、前記充電装置内の発熱部を冷却するための冷却手段を設けたことで、発熱素子等の発熱部の発熱が抑えられて、二次電池への熱伝達が防がれ、二次電池の内部での過度な化学反応（酸化還元反応）を助長することもなく、また、ユーザが二次電池があたかも発熱したかのように錯覚にとらわれることもない。この結果、二次電池は満充電状態まで適正に充電が行われて、二次電池の内部構造に損傷を与えるのを防止することができ、サイクル寿命を飛躍的に向上させることができる。
【０１４９】
また、請求項７に記載の発明では、二次電池をワンタッチで簡単に取り出すことができ、利便性が向上する。
【０１５０】
そして、請求項８に記載の発明では、ユーザが操作部材を操作することで、充電装置の座部から押上部材の一側部が出没して、二次電池をワンタッチで簡単に取り出すことができ、利便性が向上する。
【０１５１】
また、請求項９に記載の発明では、二次電池の長手方向一側部を押し下げると、該一側部が陥没部に沈み込み、二次電池の長手方向他側部が浮き上がって、該二次電池の両端子の支持が外れ、二次電池が取り出されるようになっている。このようにして、二次電池をワンタッチで簡単に取り出すことができ、利便性が向上する。
【０１５２】
そして、請求項１０に記載の発明では、充電過程で、二次電池の種類等を自動的に判別して、二次電池の内部で過度な化学反応（酸化還元反応）を引き起こすことなく、満充電状態まで適正に充電が行うことができる。また、この結果、二次電池の内部構造を傷めず、サイクル寿命を飛躍的に向上させることができる。特に、この充電装置での主なる充電は、満充電平衡電位以上の所定の充電印加電圧値で行うため、かなり大きな充電電流が流れて、充電時間の短縮を図ることができる。また、充電状態のチェックは、満充電平衡電位で行うため、精確に満充電状態まで充電することができる。
【０１５３】
また、請求項１１に記載の発明でも、充電過程で、二次電池の種類等を自動的に判別して、二次電池の内部で過度な化学反応（酸化還元反応）を引き起こすことなく、満充電状態まで適正に充電が行うことができる。また、この結果、二次電池の内部構造を傷めず、サイクル寿命を飛躍的に向上させることができる。特に、この充電装置での主なる充電は、満充電平衡電位以上の所定の充電印加電圧値で行うため、かなり大きな充電電流が流れて、充電時間の短縮を図ることができる。また、充電状態のチェックは、満充電平衡電位で行うため、精確に満充電状態まで充電することができる。
【０１５４】
さらに、請求項１２に記載の発明では、充電装置から取り出した二次電池の電池電圧は、いつでも再充電電圧値以上で、使用に適した状態にあり、利便性の向上を図ることができる。
また、この再充電においても、過度な化学反応（酸化還元反応）を引き起こすことなく、満充電状態まで適正に再充電を行うため、二次電池の内部構造に損傷を与えず、サイクル寿命を飛躍的に向上させることができるとともに、満充電までの充電時間も短くなる。
【０１５５】
そうして、請求項１３に記載の発明では、二次電池の充電状態をチェックして、所定の充電電圧で所定時間充電する一連の充電動作を繰り返し、前記充電状態のチェックで満充電状態に達したと判断されると充電を停止する二次電池の充電方法において、前記一連の充電動作間に、緩和時間を設けたことで、次の一連の充電動作での満充電状態のチェックを精確に行うことができ、信頼性が向上する。
【０１５６】
また、請求項１４に記載の発明では、各二次電池における先のターンの一連の充電動作の完了から、次のターンの一連の充電動作の開始までの間、充電が休止され、この休止期間が緩和時間となり、電極表面が安定して、次のターンでの満充電状態のチェックを精確に行うことができ、信頼性が向上する。
補足すると、二次電池の充電中、電解液と接する電極の表面で電極反応が起こり、この電極反応の過程は、電解液内部から電極表面への反応物の移動と、反応物と電極の間での電子の移動と、電極表面から電解液内部への生成物の移動との同時過程であり、この移動にはかなりの時間を要することから、二次電池の充電休止直後に、満充電状態をチェックすると、電極表面付近で電気泳動している移動過程のイオン等のために、あたかも、満充電状態に達したかのように検知されてしまうことがある。この誤検知を防ぐためにも、緩和時間を設けることは有効であり、このこの第３０発明の二次電池の充電装置では、各二次電池ごとの充電サイクルの一環として、合理的、且つ効果的に緩和時間が設けられている。
【図面の簡単な説明】
【図１】第１実施形態から第４実施形態に係る二次電池１の充電装置の構成を示すブロック図である。
【図２】二次電池１の起電力を測定するための回路図である。
【図３】二次電池１の充電率ごとの電流一電圧特性を示すグラフである。
【図４】第１実施形態に係る二次電池１の充電装置による充電制御を示すフローチャートである。
【図５】ニッケル−水素二次電池の電池端子電圧、充電電流、チェック電流の時間経過を示したグラフである。
【図６】ニッケル−カドミウム二次電池の電池端子電圧、充電電流、チェック電流の時間経過を示したグラフである。
【図７】第２実施形態に係る二次電池１の充電装置による充電制御を示すフローチャートである。
【図８】第２実施形態に係る二次電池１の充電装置による充電制御を示すフローチャートである。
【図９】第３実施形態に係る二次電池１の充電装置による充電制御を示すフローチャートである。
【図１０】第３実施形態に係る二次電池１の充電装置による充電制御を示すフローチャートである。
【図１１】第５実施形態に係る二次電池１・１・・・の充電装置５０の構成を示す平面図である。
【図１２】第６実施形態に係る二次電池１・１・・・の充電装置５０の構成を示す側面断面図である。
【図１３】第７実施形態に係る二次電池１・１・・・の充電装置５０の取出手段の構成を示す後面断面図である。
【図１４】第８実施形態に係る二次電池１・１・・・の充電装置５０の取出手段の構成を示す側面断面図である。
【符号の説明】
１ 二次電池
２ 電源部
３ 電流検出部
４ プログラム・演算制御部
５ 電圧・電流制御部
６ 充電電圧供給部
９ 電圧検出部[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a charging device and a charging method for charging a secondary battery such as a nickel-cadmium battery, a nickel-metal hydride battery, and a lead storage battery.
[0002]
[Prior art]
2. Description of the Related Art In recent years, with the development of portable devices, the use of secondary batteries has significantly increased as a power source for electronic devices such as cassette tape recorders, VTRs and computers, communication devices such as mobile phones, and power devices such as power tools. .
A secondary battery refers to a battery that can be repeatedly charged and discharged, and converts electrical energy into chemical energy and stores it, and conversely converts the stored chemical energy into electrical energy and uses it. Typical examples of the secondary batteries that are practically used include nickel-cadmium batteries, nickel-metal hydride batteries, lithium-ion batteries, and NAS batteries.
[0003]
By the way, the electromotive reaction and the discharge reaction occurring inside the secondary battery involve a chemical reaction, an electric reaction, and complicated energy conversion and energy transfer in which these two reactions are interrelated. A time factor for these various reactions is involved. Therefore, it is necessary to perform charging while taking these reactions into consideration.If the charging is performed with excessive current, the internal structure of the battery may be destroyed due to an unintended exothermic reaction or an abnormality such as swelling. is there. Even if it does not reach that point, the internal structure of this secondary battery is deteriorated, the battery life is shortened, and the number of cycles used is reduced.
[0004]
Therefore, conventionally, a program for changing the applied voltage with the progress of the charging time is incorporated in the control unit of the charging device for the secondary battery so that the secondary battery is appropriately charged, and the secondary battery is controlled according to the program. The voltage is applied to the secondary battery. Also, a number of charging devices have been filed in which a charging device is provided with a battery voltage detecting unit for detecting the voltage of a secondary battery, and the battery voltage is used as a control amount to determine and control the end of charging of the battery to be charged.
[0005]
For example, a charging device for a secondary battery disclosed in Patent Document 1 (Japanese Patent Application Laid-Open No. 8-9563) includes a voltage detection circuit that detects a negative potential difference of a charging voltage due to a constant current of the battery to be charged, A temperature detection circuit for detecting a change in battery temperature per unit time (temperature differential value) due to a current; and comparing the negative potential difference and the temperature differential value detected by the voltage detection circuit with each preset reference value. And a charge control circuit for controlling the charge switch. When the detected negative potential difference and the temperature differential value reach a negative potential difference and a temperature differential value which are preselected and set as a reference, the charging is terminated. Controlling.
[0006]
As described above, in Patent Literature 1, the control unit of the charging apparatus monitors the state of the battery to be charged using the detected value of the battery voltage or the temperature value as a control amount, and determines the charging end state.
[0007]
However, if such a charging end detection method is simply applied ignoring the state of the secondary battery, various inconveniences will occur as described below.
That is, the characteristics at the time of charging vary depending on the type of the secondary battery, such as the difference in the electrode type, the type of the electrolyte, the difference in the battery structure, and the like. The characteristics greatly vary depending on the environmental conditions at the time, the usage history of the secondary battery, the electrochemical itinerary, and the like. For this reason, charging with the same pattern as in the past may result in overcharging, which causes an abnormal chemical reaction inside the secondary battery to generate heat and convert electric energy to heat energy. Therefore, there is a problem that charging efficiency is reduced. Further, there is a danger that the internal pressure of the secondary battery rises due to the generation of gas and the liquid leaks. As a result, there is a problem that a defect occurs in the internal structure of the secondary battery required for repeated charge / discharge, and the cycle life thereof is shortened.
[0008]
Also, it is desirable that the charging time of the secondary battery is as short as possible.However, in the charging with the same pattern as described above, depending on the type of the secondary battery, the applied voltage at the time of charging may be lower than its rated value. In this case, in particular, there is a problem that it takes a considerable time to complete charging.
[0009]
In view of the above problems, the present applicant and the present applicant have proposed a secondary battery that can prevent uncharged or overcharged secondary batteries and can properly charge the batteries, and that has significantly reduced the charging time. A charging device has been invented.
[0010]
This invention is disclosed in Patent Document 2 (Japanese Patent Application Laid-Open No. 2002-199607), and is configured as follows.
This charging device for a secondary battery includes charging voltage supply means for supplying a charging voltage to the secondary battery, current detection means for detecting a current value of a charging current supplied to the secondary battery, and charging of the secondary battery. A charging control device for controlling the charging device, wherein the charging control device applies a voltage to a secondary battery having a full charge equilibrium potential and a voltage equal to or higher than the full charge equilibrium potential and having a charge rate of approximately 0%. When the applied voltage is increased, the rate of increase of the charging current with respect to the applied voltage decreases, and corresponds to a predetermined current value outside the irreversible chemical reaction region when the charging current stops increasing. Storage means for storing a predetermined charging applied voltage value to be charged, a switching means for switching the charging voltage supplied from the charging voltage supply means to the predetermined charging applied voltage value or the full charge equilibrium potential, and Detected by current detection means during application at charging equilibrium potential A current value, comprising: a comparison determination unit configured to determine a previously inputted set determination reference value, and controls the charging of the secondary battery according to the following flow.
[0011]
First, when the user manually inputs the type of the secondary battery to be charged to the charging device, a predetermined charge corresponding to the type of the secondary battery is obtained from a table stored and set in advance in the storage unit in the charging control device. An applied voltage value and a full charge equilibrium potential are selected.
[0012]
The predetermined charge applied voltage value and the full charge equilibrium potential are unique values determined by the type of nickel-cadmium secondary battery, nickel-hydrogen secondary battery, etc., their storage capacity, and the like. The nickel-hydrogen secondary battery of [mAh (milliamp hour)] has a full charge equilibrium potential of about 1.44 [V], and a predetermined charging applied voltage value of 1.60 [V].
[0013]
Next, when the user operates the operation unit to perform a charging start operation, a predetermined charging application voltage value is continuously applied to the secondary battery set in the charging device for a certain period of time. Then, after a certain period of time, the applied voltage is switched to the full charge equilibrium potential, and while the full charge equilibrium potential is applied for a short time, the current value flowing in the secondary battery at this time is detected. The detected current value is compared with the above-mentioned reference value. When the detected current value is larger than the reference value, the secondary battery is applied again at the predetermined charging applied voltage value, and the above-described flow is repeated. When the value is equal to or less than the value, control is performed to stop charging of the secondary battery.
[0014]
[Patent Document 1]
JP-A-8-9563
[0015]
[Patent Document 2]
JP 2002-199607 A
[0016]
[Problems to be solved by the invention]
As described above, the prior art is improved. In the present invention, the invention disclosed in Patent Literature 2 is improved so that the type of the secondary battery and the like can be automatically determined in the charging process. It is an object of the present invention to provide a charging device and a charging method for a secondary battery, which can rapidly and reliably charge up to full charge without causing (oxidation-reduction reaction).
[0017]
[Means for Solving the Problems]
The above is the problem to be solved by the present invention. Next, means for solving this problem will be described.
First, as described in claim 1, charging voltage supply means for supplying a charging voltage to the secondary battery, current detection means for detecting the current value of the charging current supplied to the secondary battery, A charging device for a secondary battery, comprising: voltage detecting means for detecting an applied voltage; and a charging control device for controlling charging of the secondary battery, wherein the charging control device comprises n (n is 2 or more) A natural number) of the secondary battery, the full charge equilibrium potential and the charge applied voltage value for obtaining the peak value or almost the peak value of the charge current, which exceeds the full charge equilibrium potential but is in the irreversible chemical reaction region. Storage means for storing a predetermined charging application voltage value which does not reach, switching means for switching the charging voltage supplied from the charging voltage supply means, and current detection means for detecting the charging voltage supplied at the full charge equilibrium potential. Current value and A current value judging unit for comparing and judging a charge completion reference value, and comparing the charging voltage value detected by the voltage detecting unit during charging with the predetermined charging applied voltage value with the predetermined charging applied voltage value. And voltage control means for controlling charging of the secondary battery according to the following steps.
(Step 1) Assuming that a variable is k (k = 1, 2,..., N), k is initialized and k = 1.
(Step 2) The secondary battery set in the charging device is charged for a predetermined time at a k-th predetermined charging applied voltage value among predetermined charging applied voltage values of the n types of secondary batteries.
(Step 3) If k = n, jump to Step 6.
(Step 4) While the secondary battery is being charged at the k-th lowest predetermined charging applied voltage value for a predetermined time, the voltage value applied to the secondary battery is detected by the voltage detecting means.
(Step 5) The detected voltage value is compared by the voltage value determination means, and if the voltage value is larger than the k-th lowest predetermined charge application voltage value, 1 is added to k. Then, the process returns to the step 2 as a new k. On the other hand, if the voltage value is equal to or lower than the k-th lowest predetermined charge application voltage value, the process proceeds to the next step 6.
(Step 6) The applied voltage of the secondary battery is switched to the k-th lowest full-charge equilibrium potential among the full-charge equilibrium potentials of the n types of secondary batteries.
(Step 7) While the secondary battery is being applied at the k-th lowest full-charge equilibrium potential for a short time, the current value flowing through the secondary battery is detected by the current detecting means.
(Step 8) The detected current value is determined by the current value determining means. If the detected current value is larger than the charging completion reference value, the process returns to step 2 and the above flow is repeated. If the current value is equal to or less than the charging completion reference value, charging is stopped.
[0018]
Alternatively, as described in claim 2, charging voltage supply means for supplying a charging voltage to the secondary battery, current detecting means for detecting a current value of a charging current supplied to the secondary battery, A charging device for a secondary battery, comprising: a voltage detecting unit for detecting an applied voltage; and a charging control device for controlling charging of the secondary battery, wherein the charging control device includes n (n is 2 or more). Natural battery type) secondary battery of full charge equilibrium potential and charge applied voltage value that obtains a peak value or nearly peak value of charge current, which exceeds the full charge equilibrium potential but reaches the irreversible chemical reaction region. A predetermined charge application voltage value that is not stored, a switching unit that switches a charging voltage supplied from the charging voltage supply unit, and a current detection unit that detects the voltage during the application at the full charge equilibrium potential. The current value and the Current value determining means for comparing with a charge completion reference value, a charging voltage value detected by voltage detecting means during charging at the predetermined charging applied voltage value, and a predetermined charging applied voltage value of the previous time Voltage difference determining means for determining whether the difference between the charging voltage value detected by the voltage detecting means and the charging voltage value during the charging of the battery is within a predetermined range set in advance. Controls charging of the next battery.
(Step 1) Assuming that a variable is k (k = 1, 2,..., N), k is initialized and k = 1.
(Step 2) The secondary battery set in the charging device is charged for a predetermined time at a k-th predetermined charging applied voltage value among predetermined charging applied voltage values of the n types of secondary batteries.
(Step 3) If k = n, jump to Step 6.
(Step 4) While the secondary battery is being charged at the k-th lowest predetermined charging applied voltage value for a predetermined time, the voltage value applied to the secondary battery is detected by the voltage detecting means.
(Step 5) The voltage difference detected by the voltage difference determination means during the current charging at the k-th predetermined charging applied voltage value, and the k-th predetermined charging applied voltage value at the previous time. If the difference from the voltage value detected during charging is within a predetermined range, the process proceeds to the next step 5, while if the difference exceeds a predetermined range, 1 is added to k. And returns to step 2 as a new k. However, when the current voltage value is detected for the first time, the process directly proceeds to the next step 6.
(Step 6) The applied voltage of the secondary battery is switched to the k-th lowest full-charge equilibrium potential among the full-charge equilibrium potentials of the n types of secondary batteries.
(Step 7) While the secondary battery is being applied at the k-th lowest full-charge equilibrium potential for a short time, the current value flowing through the secondary battery is detected by the current detecting means.
(Step 8) The detected current value is determined by the current value determining means. If the detected current value is larger than the charging completion reference value, the process returns to step 2 and the above flow is repeated. If the current value is equal to or less than the charging completion reference value, charging is stopped.
[0019]
As described in claim 3, charging voltage supply means for supplying a charging voltage to the secondary battery, voltage detection means for detecting the battery voltage of the secondary battery, and charging completion detected by the voltage detection means Determining means for comparing and determining the battery voltage value of the subsequent secondary battery and a recharge voltage value lower than the full-charge equilibrium potential, wherein the battery voltage value is determined by the determination means to be equal to the recharge voltage. When the value becomes equal to or less than the value, a charging voltage is supplied by the charging voltage supply means to perform recharging.
[0020]
In addition, as described in claim 4, a series of charging operations of checking the state of charge of the secondary battery and charging at a predetermined charging voltage for a predetermined time are repeated, and the state of charge reaches a fully charged state by checking the state of charge. In the charging device for a secondary battery configured to stop charging when it is determined that there is a relaxation time, a relaxation time is provided between the series of charging operations.
[0021]
Specifically, as described in claim 5, a charging device for charging a plurality of secondary batteries, a series of charging for a predetermined time at a predetermined charging voltage after checking the state of charge of the secondary batteries. The charging operation is performed alternately for each uncharged secondary battery, and this is taken as one turn. A plurality of the secondary batteries are charged while repeating the turn, and it is determined that the battery has reached the fully charged state by checking the state of charge. In the charging device for a secondary battery configured to stop charging from the recharged secondary battery, the relaxation time is, in each of the secondary batteries, from completion of a series of charging operations of a previous turn to a series of subsequent turns. Is the time until the start of the charging operation.
[0022]
Furthermore, as described in claim 6, in the charging device for a secondary battery according to any one of claims 1 to 5, a cooling unit for cooling a heat generating unit in the charging device is provided. Provide.
[0023]
According to a seventh aspect of the present invention, there is provided a charging device for charging a secondary battery, wherein a removing means for removing the secondary battery set on a seat of the charging device with one touch is provided.
[0024]
Specifically, as set forth in claim 8, the take-out means includes an operating member that is pressed down by a user, a push-up member that pushes up the secondary battery set on the seat portion, and a pivotal support for the push-up member. A rotating fulcrum shaft, and an urging means attached to the rotating fulcrum shaft for urging the push-up member in a direction opposite to the push-up direction. It is configured so that one side protrudes and disappears.
[0025]
Alternatively, as set forth in claim 9, the take-out means is configured by depressing one longitudinal side of the seat.
[0026]
According to a tenth aspect of the present invention, in the method for controlling charging of a secondary battery, a full-charge equilibrium potential and a peak value of a charging current or n (n is a natural number of 2 or more) types of secondary batteries are provided. A predetermined charging applied voltage value which is a substantially peak value and which exceeds the full charge equilibrium potential but does not reach the irreversible chemical reaction region is stored in advance in the storage means, and the following steps Charge the secondary battery according to the following.
(Step 1) Assuming that a variable is k (k = 1, 2,..., N), k is initialized and k = 1.
(Step 2) The secondary battery is charged for a predetermined period of time at a k-th predetermined charging application voltage value among predetermined charging application voltage values of n types of secondary batteries.
(Step 3) If k = n, jump to Step 6.
(Step 4) The voltage value applied to the secondary battery is detected while the secondary battery is being charged at the k-th lowest predetermined applied voltage value for a predetermined time.
(Step 5) If the detected voltage value is larger than the k-th lowest predetermined charging applied voltage value, a value obtained by adding 1 to the k is returned as a new k and the process returns to the step 2; If the detected voltage value is equal to or lower than the k-th lowest predetermined charge application voltage value, the process proceeds to the next step 6.
(Step 6) The applied voltage of the secondary battery is switched to the k-th lowest full-charge equilibrium potential among the full-charge equilibrium potentials of the n types of secondary batteries.
(Step 7) A current value flowing through the secondary battery is detected while the secondary battery is applied at the k-th lowest full charge equilibrium potential for a short time.
(Step 8) If the detected current value is larger than the charge completion reference value, the flow returns to the step 2 and the above flow is repeated. If the detected current value is equal to or less than the charge completion reference value, Stop charging.
[0027]
Alternatively, in the method for controlling the charging of a secondary battery as described in claim 11, a full charging equilibrium potential and a peak value of a charging current or n (n is a natural number of 2 or more) types of secondary batteries. A predetermined charging applied voltage value which is a substantially peak value and which exceeds the full charge equilibrium potential but does not reach the irreversible chemical reaction region is stored in advance in the storage means, and the following steps Charge the secondary battery according to the following.
(Step 1) Assuming that a variable is k (k = 1, 2,..., N), k is initialized and k = 1.
(Step 2) The secondary battery is charged for a predetermined period of time at a k-th predetermined charging application voltage value among predetermined charging application voltage values of n types of secondary batteries.
(Step 3) If k = n, jump to Step 6.
(Step 4) The voltage value applied to the secondary battery is detected while the secondary battery is being charged at the k-th lowest predetermined applied voltage value for a predetermined time.
(Step 5) The difference between the voltage value detected during charging at the k-th predetermined charging applied voltage value this time and the k-th predetermined charging applied voltage value at the previous time. If the difference from the detected voltage value is within the predetermined range, the process proceeds to the next step 6. On the other hand, if the difference exceeds the predetermined range, a value obtained by adding 1 to k is newly added. Then, the process returns to step 2 as n. However, when the current voltage value is detected for the first time, the process directly proceeds to the next step 6.
(Step 6) The applied voltage of the secondary battery is switched to the k-th lowest full-charge equilibrium potential among the full-charge equilibrium potentials of the n types of secondary batteries.
(Step 7) A current value flowing through the secondary battery is detected while the secondary battery is applied at the k-th lowest full charge equilibrium potential for a short time.
(Step 8) If the detected current value is larger than the charge completion reference value, the flow returns to the step 2 and the above flow is repeated. If the detected current value is equal to or less than the charge completion reference value, Stop charging.
[0028]
Furthermore, in the method for charging a secondary battery, a battery voltage value of the secondary battery after the completion of charging is monitored, and the battery voltage value is lower than a full charge equilibrium potential. When the voltage falls below the voltage value, recharge is performed.
[0029]
Then, the charging state of the secondary battery is checked, and a series of charging operations of charging at a predetermined charging voltage for a predetermined time are repeated, and the charging state is checked to reach a fully charged state. In the method of charging a secondary battery in which charging is stopped when it is determined that the time has reached, a relaxation time is provided between the series of charging operations.
[0030]
Specifically, as described in claim 14, a charging method for charging a plurality of secondary batteries, wherein a series of charging for a predetermined time at a predetermined charging voltage after checking a charging state of the secondary batteries. The charging operation is performed alternately for each uncharged secondary battery, and this is taken as one turn. A plurality of the secondary batteries are charged while repeating the turn, and it is determined that the battery has reached the fully charged state by checking the state of charge. In the method of charging a secondary battery in which charging is stopped from the secondary battery, the relaxation time is defined as a period of time from completion of a series of charging operations in a previous turn to a series of charging operations in a next turn in each secondary battery. It is the time between the start.
[0031]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described below with reference to the drawings.
In the charging method using the charging device for the secondary battery 1 according to the present invention, at the time of charging, the highest applied voltage (predetermined charging applied voltage value E outside the irreversible reaction region D that does not damage the internal structure of the secondary battery). _s ) Is applied to apply a large current to the secondary battery, and charging is performed while periodically checking full charge (at the end of charging). This full charge equilibrium potential E _eq In the check of the full charge state, the full charge state can be instantaneously and accurately determined. According to this charging method, (1) the time until the completion of charging can be reduced to within 30 minutes, and (1) 2) The battery can be properly charged to a fully charged state without causing an excessive chemical reaction (oxidation-reduction reaction). (3) As a result, the internal structure of the secondary battery 1 is not damaged, and the cycle life is increased to 5000 times or more. (4) During the charging process, the optimum applied voltage (full charge equilibrium potential E) for the secondary battery 1 is automatically adjusted. _eq And a predetermined charging applied voltage value E _s ) To ensure that the battery is fully charged.
[0032]
First, the basic configuration of the charging device for the secondary battery 1 according to the present invention will be described.
FIG. 1 is a block diagram showing a configuration of a charging device for a secondary battery 1 according to the present invention. Reference numeral 1 denotes a secondary battery, reference numeral 2 denotes a power supply unit, and the power supply unit 2 converts commercial AC electricity into DC. Includes transformer and rectifier circuits. Reference numeral 3 denotes a current detection unit for detecting a current value of a charging current supplied to the secondary battery 1, and reference numeral 9 denotes a voltage value applied to the secondary battery 1 or a charging voltage of the secondary battery 1. The voltage value detected by the current detection unit 3 and the voltage value detected by the voltage detection unit 9 are detected by a charge control unit that controls charging of the secondary battery 1. It is configured to transmit to a certain program / operation control unit 4.
[0033]
The program / arithmetic control unit 4 calculates a full-charge equilibrium potential E based on the type, storage capacity or model of the secondary battery 1 obtained in advance by a test or the like. _eq And the full charge equilibrium potential E _eq The above predetermined charging applied voltage value E _s (When a voltage is applied to the secondary battery 1 having a charging rate of approximately 0% and the applied voltage is increased, the rate of increase of the charging current with respect to the increase in the applied voltage (ΔI / ΔE) decreases. The current peak value I outside the irreversible chemical reaction region D when the charging current stops increasing _so A predetermined charging applied voltage value E corresponding to _s ) Is stored in the program / arithmetic control unit 4. The program / arithmetic control unit 4 determines whether the secondary battery 1 has reached a full charge, and determines the required charging time t until the full charge. A program for calculation and the like is stored.
[0034]
Reference numeral 5 denotes a voltage / current control unit that controls switching of the voltage and current applied to the secondary battery 1 based on a command from the program / operation control unit 4. That is, the voltage / current controller 5 sets the charging voltage of the secondary battery 1 to a predetermined charging applied voltage value E. _s Or full charge equilibrium potential E _eq And so on.
[0035]
Reference numeral 6 denotes a charging voltage supply unit that supplies a charging voltage determined by the voltage / current control unit 5 to the secondary battery 1 in response to a start instruction, and completes charging in response to a termination instruction from the program / operation control unit 4. It is. Reference numeral 7 denotes a display unit for displaying charging or completion of charging, and reference numeral 8 denotes an operation unit for the user to perform a start operation or the like.
[0036]
In the present embodiment, as an example of the notification means, the display unit 7 is configured to visually notify the user of charging or completion of charging, but may be configured to be notified by voice or the like. The configuration of the notification means is not particularly limited.
[0037]
As used herein, a secondary battery is a battery that can be repeatedly charged and discharged, and converts electrical energy into chemical energy and stores it, and conversely converts the stored chemical energy into electrical energy and uses it. .
Representative examples of the secondary battery 1 that are practically used include a nickel-cadmium battery, a nickel-metal hydride battery, a lithium ion battery, and a NAS battery.
Hereinafter, the nickel-cadmium battery used in each embodiment will be described.
[0038]
In a nickel-cadmium battery, a positive electrode using nickel oxyhydroxide (Ni (OOH)) and a negative electrode using cadmium (Cd) are separated by a synthetic resin separator, and are sealed together with an alkaline electrolyte in a sealed battery container. It is a stored storage battery. The electrolyte is an aqueous solution containing potassium hydroxide having high conductivity as a main component, and lithium hydroxide, sodium hydroxide, or the like is added as needed to improve the characteristics of the positive electrode.
As for the electromotive reaction of this nickel-cadmium battery, the reaction of the positive electrode is represented by the following general formula (chemical reaction formula (1)).
[0039]
Embedded image

[0040]
The reaction of the negative electrode is represented by the following general formula (chemical reaction formula).
[0041]
Embedded image

[0042]
In the reaction of the positive electrode during discharge, nickel oxyhydroxide (Ni (OOH)) and water (H ₂ O) and electrons from the positive electrode (e ⁻ ) Reacts with nickel hydroxide (Ni (OH) ₂ ) Is produced, while in the reaction of the negative electrode, cadmium (Cd) is produced at the positive electrode and hydroxide ions (OH ⁻ ) To react with cadmium hydroxide (Cd (OH) ₂ ) And electrons (e ⁻ ), And this electron (e ⁻ ) Is supplied to the positive electrode through an external load.
[0043]
In the cycle, electrons (e ⁻ ) Is used as work in the process of passing an external load. Therefore, the fact that this cycle works well means that the water (H ₂ O) rich and product nickel hydroxide (Ni (OH) ₂ ) Concentration is low, and cadmium hydroxide (Cd (OH) ₂ ) Is low. When this is expressed by a mathematical formula, the following formula (Formula (1)) is obtained.
[0044]
(Equation 1)

[0045]
Where E ⁰ Is a standard electromotive force, which is a constant determined by the materials constituting the positive electrode and the negative electrode, and does not depend on their amounts. For a nickel-cadmium battery, this standard electromotive force E ⁰ Is about 1.2 [V (volt)]. R is a gas constant, T is an absolute temperature, and F is a Faraday number.
[0046]
As shown in the above equation (1), water (H ₂ O) concentration C _aq Nickel hydroxide (Ni (OH) ₂ ) Concentration C _N Is lower, the electromotive force E _emf Cadmium hydroxide (Cd (OH) ₂ ) Concentration C _C Is lower, the electromotive force E _emf Becomes larger. Electromotive force E _emf Is large in the storage amount.
[0047]
By the way, in order to accurately know the state of charge of the secondary battery 1, the circuit shown in FIG. 2 may be formed. That is, the variable power supply 11 is connected to the secondary battery 1, and the potential of the variable power supply 11 is adjusted to a potential that balances with the electromotive force E of the secondary battery 1. That is, the variable power supply 11 is adjusted so that the current detected by the current detection unit 3 is ± 0 [mA (milliamperes)], whereby the electromotive force E of the secondary battery 1 is adjusted. _emf Is measured indirectly. Thus, the electromotive force E in the fully charged state of the secondary battery 1 _emf Is measured for each type or each model, and the data is input to the storage means of the program / operation control unit 4.
[0048]
Next, the characteristics of the charging voltage and the charging current of the secondary battery 1, which are basic in describing the charging method of the present invention, will be described based on the graph of FIG.
The horizontal axis of the graph in FIG. 3 indicates the battery terminal voltage, and the vertical axis indicates the charging current, and indicates the voltage-current characteristics of the secondary batteries 1 having different charging rates.
[0049]
That is, the curve shown by the broken line in FIG. 3 shows a state in which the charging rate of the secondary battery 1 is substantially 0% (a state in which the battery is exhausted), and in this case, the standard voltage E ⁰ Voltage E lower than (nominal voltage) _α Charging current starts to flow even if is applied. Further, the applied voltage is set to the open voltage E. _α , The charging current flowing through the secondary battery 1 increases substantially in proportion thereto, but after a predetermined voltage (inflection point in the voltage-current curve), the rate of increase of the charging current with respect to the applied voltage (ΔI / ΔE) decreases, and eventually, even if the applied voltage is increased, the charging current hardly increases, and the charging current becomes the current peak value I. _so To reach.
[0050]
This current peak value I (when the rate of increase of the charging current with respect to the applied voltage (ΔI / ΔE) becomes 0) _so The applied voltage value corresponding to _s And the predetermined charging applied voltage value E _s Is a voltage value unique to the secondary battery 1 determined by the type of the secondary battery 1 and the state of deterioration of the secondary battery 1. Thereafter, even if the applied voltage is further increased, the charging current remains for a while for a while. _so Although it does not rise as it is, the negative resistance characteristic appears inside the secondary battery 1 and the temperature rises sharply, and the charging current starts to rise again with the rise of the applied voltage. .
[0051]
The applied voltage applied to the secondary battery 1 having a charging rate of approximately 0% is equal to the predetermined charging applied voltage value E. _s Is exceeded, the oxidation-reduction reaction of the active material further proceeds inside the secondary battery 1 and enters the irreversible chemical reaction region D which causes an electrolysis reaction.
Further, in the secondary battery 1 having a charging rate of about 50% indicated by a dashed line in FIG. 3, when the applied voltage is increased (from 0 [V]), the charging current starts flowing to the secondary battery 1 Voltage E _β Is the open circuit voltage E of the secondary battery 1 having a charging rate of approximately 0%. _α Higher than. This open-circuit voltage increases as the charging rate of the secondary battery 1 increases, and the open-circuit voltage of the secondary battery 1 having a charging rate of about 90% indicated by a two-dot chain line in FIG. _γ (E _γ > E _β ), The open-circuit voltage of the secondary battery 1 having a charging rate of about 100% indicated by a solid line in FIG. _δ (E _δ > E _γ ), And the open-circuit voltage of the secondary battery 1 (in a fully charged state) having a charging rate of 100% is the full-charge equilibrium potential E described above. _eq (E _eq > E _δ ).
[0052]
When the rechargeable battery 1 exceeds the open voltage corresponding to the charging rate, the charging current increases substantially in proportion to the applied voltage, and eventually the charging current hardly increases even if the applied voltage is increased. Is the current peak value I _so To reach. The current peak value I when this charging current stops rising _so Is the predetermined charging applied voltage value E. _s And the predetermined charging applied voltage value E _s Is exceeded, the oxidation-reduction reaction of the active material proceeds further inside the secondary battery 1 and enters the irreversible chemical reaction region D which causes an electrolysis reaction.
[0053]
The irreversible reaction region D is a region indicated by oblique lines in FIG. 3. In this irreversible chemical reaction region D, an unintended exothermic reaction or abnormality such as swelling may possibly lead to destruction of the internal structure of the secondary battery 1. There is. Even if it does not reach that point, since the irreversible reaction extends and greatly affects the cycle life of the secondary battery 1, it is necessary to control the charge so as not to reach the irreversible chemical reaction region D. Required.
[0054]
By the way, the storage capacity of the secondary battery 1 is obtained by the product of the charging current and the charging time. In order to shorten the charging time, it is necessary to increase the charging current.
The terminal voltage of the secondary battery 1 having a charging rate of approximately 0% shown in FIG. _eq , And the charging current becomes I as the charging rate increases. _eqo Since the charging current becomes 0 [mA] in the fully charged state, it is easy to determine the end of charging, and since the charging does not reach the irreversible chemical reaction region D, the internal structure of the secondary battery 1 is reduced. There is no worry about damaging.
[0055]
However, this full charge equilibrium potential E _eq , The predetermined charging applied voltage value E _s The charging current is lower and the charging time is significantly longer than in the case where the battery is charged by the battery.
[0056]
From the charging characteristics described above, the charging according to the present invention is performed at the peak value I of the charging current. _so (Or approximately peak value I _so ), Which is higher than the full charge equilibrium potential but does not reach the irreversible chemical reaction region D. _s And the full charge state is determined by the full charge equilibrium potential E described above. _eq By doing so, quick charging is performed without damaging the secondary battery 1.
[0057]
Next, a first embodiment of the charging device for the secondary battery 1 will be described.
The first embodiment of the charging device for the secondary battery 1 has the basic configuration of the second embodiment and the third embodiment of the charging device for the secondary battery 1 described below.
The charging device according to the first embodiment is configured as shown in FIG. 1, and the program / operation control unit 4 includes the full charge equilibrium potential E _eq And a check current value determination program which is a determination means for comparing and determining a check current value i detected by the current detection unit 3 during application of the secondary battery 1 and a preset charge completion reference value J. Have been.
[0058]
In the charging device according to the first embodiment, the secondary battery 1 is charged with the predetermined charging applied voltage value E. _s For a fixed time T ₁ After applying high current charging, the applied voltage is changed to the full charge equilibrium potential E. _eq To the full charge equilibrium potential E _eq , The full charge equilibrium potential E _eq By comparing the detected current value i with a preset charge completion reference value J, if the current value i is larger than the charge completion reference value J, Predetermined charging applied voltage value E _s , And if the current value i is equal to or smaller than the charge completion reference value J, the charging is controlled to be stopped.
[0059]
Note that this large-current charging is performed at the predetermined charging applied voltage value E. _s However, when a voltage is applied to the secondary battery 1 having a charging rate of approximately 0% to increase the applied voltage, the rate of increase (ΔI / ΔE) of the charging current with respect to the applied voltage decreases. Then, the charging may be performed at the charging applied voltage value corresponding to the current value outside the irreversible chemical reaction region D when the charging current hardly increases. The current peak value I _so Near current flows, and large current charging can be performed.
[0060]
Next, the charging control of the secondary battery 1 by the charging device of the first embodiment will be described with reference to the flowchart shown in FIG.
First, when the user inputs the type of the secondary battery 1 to be charged from the operation unit 7 to the program / operation control unit 4, the table is stored in a storage unit in the program / operation control unit 4 in advance. A predetermined charging applied voltage value E corresponding to the type of the secondary battery 1 _s And the full charge equilibrium potential E _eq Are selected (step A1).
[0061]
This predetermined charging applied voltage value E _s And full charge equilibrium potential E _eq Is a unique value determined by the type, storage capacity, model number, and the like of a secondary battery such as a nickel-cadmium secondary battery and a nickel-hydrogen secondary battery. Equilibrium potential E _eq Is about 1.41 [V] and a predetermined charging applied voltage value E _s Is selected as about 1.80 [V] higher than that.
[0062]
Next, when the user performs a charging start operation by operating the operation unit 8 (step A2), a predetermined charging applied voltage value E is applied to the secondary battery 1. _s Is a predetermined time (constant time) T ₁ It is continuously applied (step A3).
[0063]
Here, this application time T ₁ Is set, the charging applied voltage value E _s Is determined from the change over time of the charging current when is applied. And this fixed time T ₁ After the lapse of time, the applied voltage is now fully charged equilibrium potential _eq (Step A4).
[0064]
The full charge equilibrium potential E _eq Is a small time T ₂ While the voltage is being applied, the current value i flowing through the secondary battery 1 at this time (the full charge equilibrium potential E _eq Is detected (step A5).
[0065]
Next, the detected current value i is compared with the charge completion reference value J by the check current value determination program (step A6). If the current value i is larger than the charge completion reference value J, Returning to step A3, the above-described flow (charging control) is repeated. On the other hand, if the current value i is equal to or less than the charging completion reference value J, it is determined that the secondary battery 1 has reached a fully charged state. To stop charging (step A7).
[0066]
By the way, the full charge equilibrium potential E _eq Is applied, theoretically, as shown in the graph of FIG. 3, the current value i becomes 0 [mA] at a charging rate of 100% (fully charged state). Therefore, in order to prevent overcharging due to this, it is preferable to set the charge completion reference value J to a value slightly larger than 0 [mA], for example, about 10 [mA].
[0067]
Further, the predetermined charging applied voltage value E in step A3 _s Charging time T to which is applied ₁ Varies depending on the capacity, structure, shape and the like of the secondary battery 1, for example, in the case of a nickel-cadmium secondary battery, about 55 [seconds] is selected. The full charge equilibrium potential E _eq Time T during which is applied ₂ Is about 5 seconds, and the detection of the current flowing through the secondary battery 1 in the step A5 is performed by setting the applied voltage to the full charge equilibrium potential E. _eq Is performed after 1 [sec] or more has elapsed since the switching to.
[0068]
The reason for this is that when the applied voltage is _eq Immediately after switching to, the charged electric charge remains on the electric field surface of the secondary battery 1 and the charging current to the secondary battery 1 is not stabilized. If it is detected, it is highly likely that it will not be detected accurately. _eq After the switch is made, the current value flowing through the secondary battery 1 is detected after the charging current has stabilized after waiting for 1 [sec] or more.
[0069]
Note that the predetermined charging applied voltage value E in step A3 _s After the application for a certain period of time, the applied voltage in step A4 is changed to the full charge equilibrium potential E. _eq Before switching to, the terminals of the secondary battery 1 may be short-circuited for a minimum time, for example, about 0.001 [second]. In the case of this configuration, the electric charge charged on the electric field surface of the secondary battery 1 is removed by the short circuit between the two terminals of the secondary battery 1, and the electric field surface is in a clean state. The current value can be accurately detected, and the full charge equilibrium potential E applied at the time of detecting the current value is obtained. _eq Application time T ₂ Can be set to about 0.1 [second].
[0070]
As described above, according to the charging device of the first embodiment, by detecting the current value i of the secondary battery 1 and periodically checking the state of charge thereof, excessive chemical reaction is achieved. (Oxidation-reduction reaction), it is possible to properly charge the battery to a fully charged state.
[0071]
Further, according to this charging method, damage to the internal structure of the secondary battery 1 can be prevented, so that the cycle life can be dramatically improved. Further, the main charge in this charging method is a full charge equilibrium potential E. _eq The above predetermined charging applied voltage value E _s Therefore, a considerably large charging current is passed through the secondary battery 1, thereby shortening the charging time.
[0072]
Next, a second embodiment of the charging device for the secondary battery 1 will be described.
The charging device according to the second embodiment is characterized in that the type and the like of the secondary battery 1 are automatically determined without inputting the type and the like of the secondary battery 1 and the battery can be rapidly charged to a full charge. There is. The type and the like of the secondary battery 1 referred to here include not only secondary batteries having different materials constituting the positive electrode and the negative electrode, such as a nickel-cadmium secondary battery and a nickel-hydrogen secondary battery, but also a positive electrode, It is also assumed that secondary batteries of the same type of negative electrode and different in storage capacity are included.
[0073]
Full charge equilibrium potential E of secondary battery 1 _eq And a predetermined charging applied voltage value E _s Is different depending on the type and capacity of the secondary battery. For example, the full-charge equilibrium potential of a nickel-cadmium secondary battery having a storage capacity of 1000 [mAh (milliamp-hour)] is about 1.41 [V]. The predetermined charging applied voltage value is about 1.80 [V], and the full charge equilibrium potential of a nickel-hydrogen secondary battery having a storage capacity of 2000 [mAh] is about 1.44 [V]. The charge applied voltage value is 1.60 [V].
[0074]
FIG. 5 shows a nickel-hydrogen rechargeable battery of the first embodiment with a full charge equilibrium potential of 1.44 [V] and a predetermined applied voltage of 1.60 [V]. FIG. 6 is a diagram showing a battery terminal voltage, a charging current, and a lapse of time of a check current when a nickel-hydrogen secondary battery is charged at a set voltage value corresponding to a secondary battery. FIG. In the charging device for the secondary battery 1, the full charge equilibrium potential is set to 1.44 [V], and a predetermined charging applied voltage value is set to 1.60 [V]. FIG. 4 is a diagram showing the time course of a battery terminal voltage, a charging current, and a check current when a cadmium secondary battery is charged. 5 and 6, a predetermined time T for applying the predetermined charging applied voltage value of 1.60 [V] in step A3 is used. ₁ Is set to 55 seconds, and the short circuit in step A4 is not performed, and the short time T for applying the full charge equilibrium potential of 1.44 [V] in step A5 is used. ₃ Is 5 seconds.
[0075]
In addition, there is a predetermined resistance between the power supply unit 2, the voltage / current control unit 5, and the charging voltage supply unit 6 shown in FIG. 1, and in the setting corresponding to the nickel-hydrogen secondary battery, the power is supplied from the power supply unit 2. 2.0 [V], a voltage drop occurs between the power supply unit 2, the voltage / current control unit 5, and the charging voltage supply unit 6, and the voltage drops between the terminals of the nickel-hydrogen secondary battery. , About 1.6 [V] are applied.
[0076]
Here, as shown in FIG. 3, the secondary battery 1 is charged with a predetermined charging applied voltage value E. _s , A constant charging current (current peak value I _so ) Flows. On the other hand, the secondary battery 1 is charged with a predetermined charging applied voltage value E. _s When the voltage is applied at a lower voltage value, the charging current flowing through the secondary battery 1 decreases as the charging rate increases.
[0077]
From such characteristics, as shown in FIG. 5, when the nickel-hydrogen secondary battery is charged at a set voltage value corresponding to the nickel-hydrogen secondary battery, the voltage between the terminals of the nickel-hydrogen secondary battery is A voltage of about 1.6 [V] corresponding to a predetermined charging applied voltage value (1.60 [V]) of the nickel-hydrogen secondary battery is applied, and a predetermined charging applied voltage value corresponding to the predetermined charging applied voltage value is applied. Current (current peak value I _so ) Is conducted, and as a result, the voltage drop between the power supply unit 2, the voltage / current control unit 5, and the charging voltage supply unit 6 is also substantially constant. That is, the voltage between the terminals of the nickel-hydrogen secondary battery is substantially constant without exceeding 1.6 [V] from the start of charging to the completion of charging, and the charging current is also substantially constant from the start of charging to the completion of charging. Also, periodically, the check current is properly checked by the full charge equilibrium potential of 1.44 [V] of the nickel-hydrogen secondary battery, and the nickel-hydrogen secondary battery is rapidly and properly charged to full charge. can do.
[0078]
On the other hand, as shown in FIG. 6, when the nickel-cadmium secondary battery is charged at the set voltage value corresponding to the nickel-hydrogen secondary battery, the terminal of the nickel-cadmium secondary battery is maintained for a while after the start of charging. A voltage of 1.4 [V] to 1.6 [V] is applied between them. This is a voltage value lower than a predetermined charging applied voltage value (1.80 [V]) of the nickel-cadmium secondary battery. As a result, as the charging rate increases, the nickel-cadmium secondary battery increases. The charging current flowing through the battery gradually decreases. Accordingly, the voltage drop between the power supply unit 2, the voltage / current control unit 5, and the charging voltage supply unit 6 also gradually decreases, and as a result, the voltage between the terminals of the nickel-cadmium secondary battery is reduced. The value of the applied voltage gradually increases and eventually exceeds 1.6 [V], and reaches about 1.8 [V] when the charging is completed.
[0079]
In addition, the check current is regularly checked based on the full charge equilibrium potential of the nickel-hydrogen secondary battery of 1.44 [V]. The full charge equilibrium potential of this nickel-hydrogen secondary battery is 1.44 [V]. V] is higher than the full-charge equilibrium potential of the nickel-cadmium secondary battery of 1.41 [V], so that the nickel-cadmium secondary battery cannot be charged until it is fully charged.
[0080]
Therefore, in the charging device according to the second embodiment, a case where a nickel-hydrogen secondary battery and a nickel-cadmium secondary battery are discriminated will be described as an example. At the corresponding voltage value, charging and the state of charge are checked. If the terminal voltage of the secondary battery 1 exceeds 1.6 [V] in the charging process, the secondary battery 1 is charged with nickel-cadmium. After determining that the battery is a secondary battery, the secondary battery 1 is charged with a voltage value corresponding to the nickel-cadmium secondary battery, and the state of charge is checked.
[0081]
To be more specific, the charging device according to the second embodiment is also configured as shown in FIG. 1, and the storage means (memory) of the program / operation control unit 4 stores a plurality of secondary batteries. Full charge equilibrium potential E _eq And a predetermined charging applied voltage value E _s Are stored. Further, the program / arithmetic control unit 4 stores the rechargeable battery 1 in a fully charged equilibrium potential E. _eq A check current value determination program which is a determination means for comparing and determining a check current value i detected by the current detection unit 3 during the application with a preset charge completion reference value J; Applied voltage value E of _s The charging voltage value e detected by the voltage detecting unit 9 during charging with the predetermined charging applied voltage value E _s And a charging voltage value determination program as a determination means for comparing and determining.
The other configurations of the charging device according to the second embodiment are substantially the same as those of the charging device according to the first embodiment, and thus description thereof will be omitted.
[0082]
First, for the sake of simplicity, the storage means of the program / operation control unit 4 stores the full charge equilibrium potential E of the two types of secondary batteries. _eq (E _eql ・ E _eqh ) And a predetermined charging applied voltage value E _s (E _sl ・ E _sh ) Will be described with reference to the flowchart shown in FIG. 7.
Here, for the full charge equilibrium potential, E _eql <E _eqh For a given charging applied voltage value, E _sl <E _sh And
[0083]
First, when the user operates the operation unit 8 to perform a charging start operation (step B1), the secondary battery 1 set in the charging device has a lower charging application voltage value of the predetermined charging applied voltage of the two types of secondary batteries. Predetermined charging applied voltage value E _sl For a predetermined time (constant time) T ₁ It is continuously applied (step B2).
[0084]
Then, the secondary battery 1 is charged with the lower predetermined charging applied voltage value E. _sl For a fixed time T ₁ During the charging, the voltage detector 9 detects the voltage value e applied to the secondary battery 1 (step B3), and determines the detected voltage value e by the charging voltage value determination program. (Step B4), the voltage value e is the lower predetermined charging applied voltage value E _sl If the voltage value is larger than the predetermined charging application voltage value E, the process jumps to step B10 described later. _sl If it is below, the process proceeds to the next step B5.
[0085]
The fixed time T ₁ After the lapse of time, the applied voltage of the secondary battery 1 is changed to the lower one of the two types of full-charge equilibrium potentials of the full-charge equilibrium potentials E. _eql To recharge the secondary battery 1 with the lower full-charge equilibrium potential E _eql For a short time T ₂ Apply (Step B5).
[0086]
Next, the secondary battery 1 is charged with the lower full charge equilibrium potential E. _eql For a short time T ₂ While the voltage is being applied, the current detector 3 detects the current value i flowing through the secondary battery 1 (step B6).
Then, the detected current value i is determined by the check current value determination program (step B7). If the current value i is larger than the charge completion reference value J, the flow returns to step B2 to return to the above flow. On the other hand, if the current value i is equal to or less than the charge completion reference value J, the charging is stopped (step B8).
[0087]
On the other hand, in step B4, the secondary battery 1 is charged with the lower predetermined charging applied voltage value E. _sl For a fixed time T ₁ During charging, the voltage value e detected by the voltage detection unit 9 is lower than the lower predetermined charging applied voltage value E. _sl If the value is larger than the predetermined voltage, the applied voltage of the secondary battery 1 is set to the higher predetermined applied voltage E of the predetermined applied voltages of the two types of secondary batteries. _sh And the higher predetermined charging applied voltage value E _sh For a fixed time T ₁ The application is continued (step B9).
[0088]
The fixed time T ₁ After a lapse of time, the applied voltage of the secondary battery 1 is changed to the higher full-charge equilibrium potential E of the full-charge equilibrium potentials of the two types of secondary batteries. _eqh To recharge the secondary battery 1 with the higher full-charge equilibrium potential E _eqh For a short time T ₃ Apply (Step B10).
[0089]
Next, the secondary battery 1 is charged with the higher full-charge equilibrium potential E. _eqh For a short time T ₃ While the voltage is being applied, the current detector 3 detects a current value i flowing through the secondary battery 1 (step B11).
The detected current value i is determined by the check current value determination program (step B12). If the current value i is larger than the charge completion reference value J, the flow returns to step B9 to return to the above flow. When the current value i is equal to or smaller than the charge completion reference value J, the charging is stopped (step B9).
[0090]
As described above, the storage means of the program / arithmetic control unit 4 stores the full charge equilibrium potential E for the two types of secondary batteries. _eql ・ E _eqh And a predetermined charging applied voltage value E _sl ・ E _sh This is an explanation of the charging control of the secondary battery 1 by the charging device in which is stored.
[0091]
Next, generally, the storage means of the program / arithmetic control unit 4 stores the full charge equilibrium potential E for n (n is a natural number of 2 or more) types of secondary batteries. _eq (E _eq1 , E _eq2 , ..., E _eqn ), Predetermined charging applied voltage value E _s (E _s1 , E _s2 , ..., E _sn ) Will be described with reference to a flowchart shown in FIG. 8.
Here, the full charge equilibrium potential is E _eq1 <E _eq2 , ..., <E _eqn And the predetermined charging applied voltage value is E _s1 <E _s2 , ..., <E _sn And
[0092]
First, here, the variable is set to k (k = 1, 2,..., N), k is initialized, and k = 1 (step C1). Next, when the user operates the operation unit 8 to perform a charging start operation (step C2), the secondary battery 1 set in the charging device has the nth of the predetermined charging applied voltage values of the secondary battery among the secondary battery 1. The k-th lowest predetermined charging applied voltage value E _sk For a predetermined time (constant time) T ₁ It is continuously applied (Step C3).
[0093]
Here, when k = n (step C4), the process jumps to step C8 described later, and when k ≦ n−1, the secondary battery 1 is charged with the k-th lowest predetermined charging applied voltage value E. _sk For a fixed time T ₁ During charging, the voltage detecting section 9 detects the voltage value e applied to the secondary battery 1 (step C5), and determines the detected voltage value e by the charging voltage value determining program. (Step C6) The predetermined charging application voltage value E whose voltage value e is the k-th lowest. _sk If a higher value is detected, a value obtained by adding 1 to the k is set as a new k (step C7), the process returns to the step C3, and the predetermined charge application in which the voltage value e is the k-th lowest is performed. Voltage value E _sk If detected below, the process proceeds to step C8.
[0094]
The fixed time T ₁ After the passage of time, the applied voltage of the secondary battery 1 is changed to the k-th lowest full-charge equilibrium potential E among the full-charge equilibrium potentials of the n types of secondary batteries. _eqk And the k-th lowest full-charge equilibrium potential E _eqk For a short time T ₂ Apply (Step C8).
[0095]
Next, the secondary battery 1 is charged with the k-th lowest full charge equilibrium potential E. _eqk For a short time T ₂ While the voltage is being applied, the current detector 3 detects a current value i flowing through the secondary battery 1 (step C9).
[0096]
The detected current value i is determined by the check current value determination program (step C10). If the current value i is larger than the charge completion reference value J, the flow returns to step C3 to return to the above-described flow. When the current value i is equal to or less than the charge completion reference value J, the charging is stopped (step C11).
[0097]
It should be noted that after the voltage is applied for a certain period of time at the predetermined charging applied voltage value in step B2 (or step B9, step C3), the applied voltage in step B5 (or step B10, step C8) is fully charged. Before switching to the equilibrium potential, the two terminals of the secondary battery 1 may be short-circuited for a minimum time, for example, about 0.001 [second]. In the case of this configuration, the electric charge charged on the electric field surface of the secondary battery 1 is removed by the short circuit between the two terminals of the secondary battery 1, and the electric field surface is in a clean state. The current value can be accurately detected, and the full charge equilibrium potential E applied at the time of detecting the current value is obtained. _eq Application time T ₂ Can be set to about 0.1 [second].
[0098]
As described above, according to the charging device of the second embodiment, the same effects as those of the charging device of the first embodiment can be obtained, and the type and the like of the secondary battery 1 can be automatically determined in the charging process. The battery can be charged quickly and properly up to full charge without causing excessive chemical reaction (redox reaction).
[0099]
Next, a third embodiment of the charging device for the secondary battery 1 will be described.
The charging device according to the third embodiment has a predetermined charging applied voltage value E _s The charging voltage value e detected by the voltage detecting unit 9 during the charging at _s It is determined whether the difference Δe from the charging voltage value e detected by the voltage detection unit 9 during the charging in step S is within a predetermined range W set in advance, and if the difference Δe exceeds the predetermined range W. For example, the full-charge equilibrium potential E corresponding to another type of secondary battery 1 _eq And a predetermined charging applied voltage value E _s The difference from the charging device according to the second embodiment is that the charging device is configured to switch to and charge.
[0100]
The charging device of the third embodiment is also configured as shown in FIG. 1, and the storage means (memory) of the program / arithmetic control unit 4 stores a full charge equilibrium potential E of a plurality of secondary batteries. _eq And a predetermined charging applied voltage value E _s Are stored. Further, the program / arithmetic control unit 4 stores the rechargeable battery 1 in a fully charged equilibrium potential E. _eq A check current value judging program as judging means for comparing and judging a check current value i detected by the current detecting section 3 during application with a preset charge completion reference value J; Value E _s The charging voltage value e detected by the voltage detecting unit 9 during the charging at _s And a voltage difference determination program that is a determination unit that determines whether a difference Δe from the charging voltage value e detected by the voltage detection unit 9 during the charging in step S is within a predetermined range W set in advance. It has been incorporated.
The other configuration of the charging device according to the third embodiment is substantially the same as that of the charging device according to the first embodiment, and a description thereof will be omitted.
[0101]
First, for the sake of simplicity, the storage means of the program / operation control unit 4 stores the full charge equilibrium potential E of the two types of secondary batteries. _eq (E _eql ・ E _eqh ) And a predetermined charging applied voltage value E _s (E _sl ・ E _sh ) Will be described with reference to the flowchart shown in FIG. 9.
Here, for the full charge equilibrium potential, E _eql <E _eqh For a given charging applied voltage value, E _sl <E _sh And
[0102]
First, when the user operates the operation unit 8 to perform a charging start operation (step D1), the secondary battery 1 set in the charging device has a lower charging application voltage value of the two types of secondary batteries. Predetermined charging applied voltage value E _sl For a predetermined time (constant time) T ₁ It is continuously applied (step D2).
[0103]
Then, the secondary battery 1 is charged with the lower predetermined charging applied voltage value E. _sl For a fixed time T ₁ During charging, the voltage value e applied to the secondary battery 1 is detected by the voltage detecting unit 9 (step D3), and the lower voltage is applied to the lower predetermined charging applied voltage by the voltage difference determination program. Value E _sl The voltage value e detected while charging the battery with the previously determined lower predetermined charging applied voltage value E _sl It is determined whether the difference Δe from the voltage value e detected while charging is within the predetermined range W (step D4). If the difference Δe is within the predetermined range W, the following is performed. The process proceeds to step D5, and if the difference Δe exceeds the predetermined range W, the process jumps to step D10 described later. However, when the detection of the current voltage value e is the first time, the process directly proceeds to the next step D5.
[0104]
The fixed time T ₁ After the lapse of time, the applied voltage of the secondary battery 1 is changed to the lower one of the two types of full-charge equilibrium potentials of the full-charge equilibrium potentials E. _eql To recharge the secondary battery 1 with the lower full-charge equilibrium potential E _eql For a short time T ₂ Apply (Step D5).
[0105]
Next, the secondary battery 1 is charged with the lower full charge equilibrium potential E. _eql For a short time T ₂ While the voltage is being applied, the current detector 3 detects a current value i flowing through the secondary battery 1 (step D6).
Then, the detected current value i is determined by the check current value determination program (step D7). If the current value i is larger than the charge completion reference value J, the process returns to step D2 to return to the above-described flow. If the current value i is equal to or less than the charge completion reference value J, the charging is stopped (step D8).
[0106]
On the other hand, in step D4, if the difference Δe exceeds the predetermined range W, the applied voltage of the secondary battery 1 is set to the higher of the predetermined charging applied voltage values of the two types of secondary batteries. Predetermined charging applied voltage value E _sh And the higher predetermined charging applied voltage value E _sh For a predetermined time (constant time) T ₁ The application is continued (step D9).
[0107]
The fixed time T ₁ After a lapse of time, the applied voltage of the secondary battery 1 is changed to the higher full-charge equilibrium potential E of the full-charge equilibrium potentials of the two types of secondary batteries. _eqh To recharge the secondary battery 1 with the higher full-charge equilibrium potential E _eqh For a short time T ₂ Apply (Step D10).
[0108]
Next, the secondary battery 1 is charged with the higher full-charge equilibrium potential E. _eqh For a short time T ₂ While the voltage is being applied, the current detector 3 detects a current value i flowing through the secondary battery 1 (step D11).
[0109]
Then, the detected current value i is determined by the check current value determination program (step D12). If the current value i is larger than the charge completion reference value J, the flow returns to step D9 to return to the above-described flow. If the current value i is equal to or less than the charge completion reference value J, the charging is stopped (step D8).
[0110]
As described above, the storage means of the program / arithmetic control unit 4 stores the full charge equilibrium potential E for the two types of secondary batteries. _eql ・ E _eqh And a predetermined charging applied voltage value E _sl ・ E _sh This is an explanation of the charging control of the secondary battery 1 by the charging device in which is stored.
Next, generally, the storage means of the program / arithmetic control unit 4 stores the full charge equilibrium potential E for n (n is a natural number of 2 or more) types of secondary batteries. _eq (E _eq1 , E _eq2 , ..., E _eqn ), Predetermined charging applied voltage value E _s (E _s1 , E _s2 , ..., E _sn ) Will be described with reference to the flowchart shown in FIG. 10.
Here, the full charge equilibrium potential is E _eq1 <E _eq2 , ..., <E _eqn And the predetermined charging applied voltage value is E _s1 <E _s2 , ..., <E _sn And
[0111]
First, here, the variable is set to k (k = 1, 2,..., N), k is initialized, and k = 1 (step F1). Next, when the user operates the operation unit 8 to perform a charging start operation (step F2), the secondary battery 1 set in the charging device has the nth of the predetermined charging applied voltage values of the secondary charging batteries of the secondary batteries. The k-th lowest predetermined charging applied voltage value E _sk For a predetermined time (constant time) T ₁ It is continuously applied (step F3).
[0112]
Here, when k = n (step F4), the processing jumps to step F8 described later, and when k ≦ n−1, the secondary battery 1 is charged with the k-th lowest predetermined charging applied voltage value E. _sk For a fixed time T ₁ During charging, the voltage detecting section 9 detects the voltage value e applied to the secondary battery 1 (step F5), and the voltage difference determination program determines that the k-th predetermined predetermined charging is performed. Applied voltage value E _sk And the voltage value E detected during charging with the k-th predetermined charge application voltage value E last time. _sk It is determined whether the difference Δe from the voltage value e detected while charging is within the predetermined range W (step F6). If the difference Δe is within the predetermined range W, the process proceeds to step F8. If the difference Δe exceeds the predetermined range W, a value obtained by adding 1 to k is set as a new k (step F7), and the process returns to step F3. However, when the current voltage value e is detected for the first time, the process proceeds to step F8.
[0113]
The fixed time T ₁ After the passage of time, the applied voltage of the secondary battery 1 is changed to the k-th lowest full-charge equilibrium potential E among the full-charge equilibrium potentials of the n types of secondary batteries. _eqk And the k-th lowest full-charge equilibrium potential E _eqk For a short time T ₂ Apply (Step F8).
[0114]
Next, the secondary battery 1 is charged with the k-th lowest full charge equilibrium potential E. _eqk For a short time T ₂ While the voltage is being applied, the current detector 3 detects a current value i flowing through the secondary battery 1 (step F9).
[0115]
The detected current value i is determined by the check current value determination program (step F10). If the current value i is larger than the charge completion reference value J, the flow returns to step F3 to return to the above-described flow. When the current value i is equal to or smaller than the charge completion reference value J, the charging is stopped (step F11).
[0116]
It should be noted that the voltage applied at the step D2 (or step D9, step F3) is fully charged after the voltage is applied for a certain period of time at the predetermined charging applied voltage value at step D5 (or step D10, step F8). Before switching to the equilibrium potential, the two terminals of the secondary battery 1 may be short-circuited for a minimum time, for example, about 0.001 [sec]. In the case of this configuration, the electric charge charged on the electric field surface of the secondary battery 1 is removed by the short circuit between the two terminals of the secondary battery 1, and the electric field surface is in a clean state. The current value can be accurately detected, and the full charge equilibrium potential E applied at the time of detecting the current value is obtained. _eq Application time T ₂ Can be set to about 0.1 [second].
[0117]
As described above, the charging device according to the third embodiment also has the same effect as the charging device according to the first embodiment, and automatically determines the type of the secondary battery 1 in the charging process, Charging can be performed quickly and properly to full charge without causing an excessive chemical reaction (oxidation-reduction reaction).
[0118]
Next, a fourth embodiment of the charging device for the secondary battery 1 will be described.
If the secondary battery 1 is left after charging is completed, it will self-discharge and the battery voltage will gradually decrease. For example, if the secondary battery 1 is left for two days, the battery voltage will decrease by about 15%. If left for 30 days, the battery voltage drops by about 40%. Therefore, when the secondary battery 1 is used for a device such as a digital camera, the battery voltage may be too low to be useful.
[0119]
Therefore, in the charging device according to the fourth embodiment, the secondary battery that has been charged by any one of the first to twelfth embodiments or by a method other than the above embodiment is used. When the battery voltage of No. 1 becomes equal to or less than a predetermined voltage, recharging is performed.
[0120]
The charging device of the fourth embodiment is also configured as shown in FIG. 1, and the program / arithmetic control unit 4 stores the battery voltage value of the secondary battery 1 after the completion of the charging detected by the voltage detecting unit 9. And the full charge equilibrium potential E _eq Lower recharge voltage value E _r And a recharge determination program as determination means for comparing and determining.
[0121]
This recharge voltage value E _r Is, for example, the full charge equilibrium potential E _eq The battery voltage of the secondary battery 1 set in the charging device is monitored by the voltage detection unit 9 even after the charging is completed, and the battery voltage value of the secondary battery 1 is reset. Charge voltage value E _r When the following occurs, a recharge command is output from the program / operation control unit 4, a charging voltage is supplied from the charging voltage supply unit 6, and the secondary battery 1 is recharged. I have.
[0122]
The stop of the recharging is performed according to the charging stop condition of any one of the first to third embodiments, or in the case of a charging apparatus using a method other than the above-described embodiment. The condition for stopping charging of the charging device shall be followed.
[0123]
As described above, if the battery is configured to be recharged, the battery voltage of the secondary battery 1 taken out of the charging device can be changed to the recharge voltage value E at any time. _r The above is in a state suitable for use, and convenience can be improved.
Also, in this recharging, since the recharge is properly performed to a fully charged state without causing an excessive chemical reaction (redox reaction), the internal structure of the secondary battery 1 is not damaged, and the cycle life is shortened. It can be dramatically improved, and the charging time until full charging is shortened.
[0124]
Next, a fifth embodiment of the charging device for the secondary batteries 1, 1... Will be described.
FIG. 11 is a plan view showing the configuration of the charging device of the fifth embodiment of the charging device for the secondary batteries 1, 1..., And the charging device 50 according to the fifth embodiment includes a plurality of secondary batteries 1. ... (In this embodiment, four secondary batteries 1...) Are charged.
[0125]
In FIG. 11, reference numeral 50a denotes a seat for setting the secondary battery 1, and reference numeral 50b denotes an outside air intake. Reference numeral 51 denotes a first display unit, which lights when the secondary battery 1 set in the seat 50a is almost fully charged. For example, the battery voltage of the secondary battery 1 is changed to the recharge voltage value E. _r It is configured to light up when it reaches. In the case of this setting, the recharging is executed when the first display unit 51 which is lit once after charging is turned off. Reference numeral 52 denotes a second display unit, which corresponds to the secondary battery 1 currently being charged among the secondary batteries 1,... Which are charged alternately in the order of the bold arrows in FIG. When the secondary battery 1 reaches a fully charged state and charging is completed, the second display unit 52 corresponding to the secondary battery 1 is turned on. Reference numeral 53 denotes a takeout button for taking out the secondary battery 1 set in the seat portion 50a of the secondary battery 1, reference numeral 54 denotes a start button for starting charging of the secondary batteries 1,. Is a power lamp, and the charging device 50 is connected to a commercial power supply via a power cord (not shown).
[0126]
The charging device 50 according to the fifth embodiment checks the state of charge of the secondary battery 1 and then performs a series of charging operations of charging at a predetermined voltage for a predetermined time for each uncharged secondary battery 1 in FIG. Are alternately performed in the order of the bold arrows, and this is defined as one turn, and the plurality of rechargeable batteries 1,... Are charged while repeating this turn. The rechargeable battery 1 is configured to stop charging.
Note that the secondary battery 1 that has reached a fully charged state is skipped (skipped) in the next turn. Further, the order in which the secondary battery 1 is charged in each turn is not limited to the order indicated by the thick arrow in FIG. 11, and may be performed in another order.
[0127]
The charge state is checked, for example, by determining the charge current value i in step A6 in the first embodiment, or by determining the charge current value i in step B7, step B12, or step C10 in the second embodiment. Alternatively, the determination is made by determining the charging current value i in step D7, step D12, or step F10 in the third embodiment, and the charging voltage includes, for example, the predetermined charging applied voltage value E. _s Is used.
[0128]
The charging device 50 is configured as described above. In the charging device 50, charging is performed from the completion of a series of charging operations in the previous turn in each secondary battery 1 to the start of a series of charging operations in the next turn. Is stopped, and this rest period becomes a relaxation time, the electrode surface is stabilized, the full charge state can be checked accurately in the next turn, and the reliability is improved.
[0129]
Supplementally, during the charging of the secondary battery 1, an electrode reaction occurs on the surface of the electrode in contact with the electrolytic solution, and the process of this electrode reaction is the movement of the reactant from inside the electrolytic solution to the electrode surface and the reaction between the reactant and the electrode. The transfer of electrons between the electrodes and the transfer of the product from the electrode surface to the inside of the electrolytic solution are simultaneous processes. Since this transfer requires a considerable amount of time, the charge of the secondary battery 1 is stopped immediately after the charging is stopped. When the state of charge is checked, it may be detected as if the battery has reached a fully charged state due to ions or the like in the movement process of electrophoresis near the electrode surface. In order to prevent this erroneous detection, it is effective to provide a relaxation time, and in the charging device 50 of the fifth embodiment, as a part of the charging cycle for each of the secondary batteries 1, 1. And an effective relaxation time is provided.
[0130]
It should be noted that also in the first to third embodiments, in each of the secondary batteries 1, a certain time T ₁ May be configured to provide a relaxation time between the charging of the battery and the subsequent check of the charging state.
[0131]
Next, a sixth embodiment of the charging device for the secondary battery 1 will be described.
As shown in FIG. 12, a cooling fan 61 is provided as a cooling means inside the charging device 50 of the sixth embodiment. The charging of the secondary battery 1 by the charging device 50 of the sixth embodiment is performed as shown in any one of the first to fifth embodiments. No excessive chemical reaction occurs inside, and the secondary battery 1 itself does not generate heat. However, since a resistor or the like of an electronic component for controlling charging generates heat, a cooling fan 61 is provided to cool the heating elements 64 and 65 such as the resistor.
12, reference numeral 50C denotes a casing which is a casing of the charging device 50, reference numeral 50b denotes an outside air intake port provided on one side of the surface of the casing 50C (see FIG. 11), and reference numeral 50d denotes one side of the back surface of the casing 50C. The outside air intake port provided in the section, reference numeral 50e is an exhaust port provided on the other side of the rear surface of the casing 50C, and the reference numeral 50h is a leg supporting the casing 50C. Reference numerals 62 and 63 are substrates, and reference numerals 64 and 65 are heating elements such as resistors.
[0132]
As described above, the charging device 50 is configured, and by operating the cooling fan 61, the outside air around the casing 50C is taken in from the outside air intake ports 50b and 50d, and the outside air is applied to the surfaces of the heating elements 64 and 65. As a result, the heat generating elements 64 and 65 are cooled. Then, the taken-in outside air is drawn further inward by the cooling fan 61 and is exhausted from the exhaust port 50e.
[0133]
With the above configuration, heat generation of the heating elements 64 and 65 is suppressed, heat transfer to the secondary battery 1 is prevented, and excessive chemical reaction (oxidation-reduction reaction) inside the secondary battery 1 is prevented. The user is not encouraged, and the user is not confused by the illusion as if the secondary battery 1 generated heat. As a result, the rechargeable battery 1 is properly charged to a fully charged state, damage to the internal structure of the rechargeable battery 1 can be prevented, and cycle life can be significantly improved. .
[0134]
Next, a seventh embodiment of the charging device for the secondary battery 1 will be described.
The charging device 50 according to the seventh embodiment is provided with a take-out means for taking out the secondary battery 1 set in the charging device 50 with one touch.
[0135]
As shown in FIGS. 11 and 13, the removal means of the charging device 50 of the seventh embodiment includes a removal button 53 pressed down by the user and the secondary battery 1 set in the seat 50 a of the charging device 50. It includes a push-up member 57 that pushes up, a pivot point shaft 58 that supports the push-up member 57, and a torsion spring 59 that is attached to the pivot point shaft 58 and urges the push-up member 57 in a direction opposite to the push-up direction. ing.
[0136]
With the above configuration, as shown in FIG. 13B, when the user presses the ejection button 53, which is an operation member, the lower end of the ejection button 53 pushes down the other side of the push-up member 57, and the rotation fulcrum. With the shaft 58 as a fulcrum, one side of the push-up member 57 rises from the seat 50a, whereby the secondary battery 1 is pushed up and the support of both terminals of the secondary battery 1 is released. ing.
[0137]
Then, as shown in FIG. 13 (a), when the user releases the ejection button 53, the one side of the push-up member 57 is returned to the original seat portion 50a by the restoring force of the torsion spring 59 as the urging means. To a position along the concave curved surface of, and the state in which the secondary battery 1 can be set is enabled.
[0138]
As described above, when the user operates the take-out button 53, one side of the push-up member 57 protrudes and retracts from the seat portion 50a of the charging device 50, and the secondary battery 1 is taken out. With such a configuration, the secondary battery 1 can be easily taken out with one touch, and the convenience is improved.
[0139]
Next, an eighth embodiment of the charging device for the secondary battery 1 will be described.
The charging device 50 of the eighth embodiment is provided with a take-out unit of a different form from the take-out unit of the seventh embodiment.
[0140]
As shown in FIG. 14, the removing means of the charging device 50 of the eighth embodiment has a configuration in which one longitudinal side of a seat portion 50a of the charging device 50 is depressed, and is set in the depressed portion 50k. One side (one side in the longitudinal direction) of the secondary battery 1 is in a state of being suspended in the air.
[0141]
As shown in FIGS. 14A and 14B, when one side of the secondary battery 1 is pushed down, the one side sinks into the depression 50k, and the other side of the secondary battery 1 floats up. The support of both terminals of the secondary battery 1 is released, and the secondary battery 1 is taken out. With such a configuration, the secondary battery 1 can be easily taken out with one touch, and the convenience is improved.
[0142]
Although the first to eighth embodiments of the charging device for the secondary battery 1 have been described above, the present invention is not limited to the above-described embodiment, and may be implemented with various modifications within the scope of the claims. It is possible to do.
[0143]
【The invention's effect】
The present invention configured as described above has the following effects.
First, according to the first aspect of the present invention, during the charging process, the type of the secondary battery or the like is automatically determined, and the secondary battery is fully charged without causing an excessive chemical reaction (oxidation-reduction reaction) inside the secondary battery. Charging can be properly performed up to the charging state. As a result, the cycle life can be significantly improved without damaging the internal structure of the secondary battery. In particular, since the main charging in this charging device is performed at a predetermined charging applied voltage value equal to or higher than the full charging equilibrium potential, a considerably large charging current flows, and the charging time can be reduced. In addition, since the charge state is checked at the full charge equilibrium potential, the battery can be charged to the full charge state accurately.
[0144]
According to the second aspect of the present invention, during the charging process, the type of the secondary battery is automatically determined, and the secondary battery is fully charged without causing an excessive chemical reaction (oxidation-reduction reaction) inside the secondary battery. Charging can be properly performed up to the charging state. As a result, the cycle life can be significantly improved without damaging the internal structure of the secondary battery. In particular, since the main charging in this charging device is performed at a predetermined charging applied voltage value equal to or higher than the full charging equilibrium potential, a considerably large charging current flows, and the charging time can be reduced. In addition, since the charge state is checked at the full charge equilibrium potential, the battery can be charged to the full charge state accurately.
[0145]
According to the third aspect of the present invention, the battery voltage of the secondary battery taken out of the charging device is always higher than the recharge voltage value, and is in a state suitable for use, so that the convenience can be improved.
Also, in this recharging, the recharge is properly performed until the battery is fully charged without causing an excessive chemical reaction (redox reaction), so that the internal structure of the secondary battery is not damaged and the cycle life is increased. And the charging time until full charging is shortened.
[0146]
Further, in the invention according to claim 4, the charging state of the secondary battery is checked, a series of charging operations of charging at a predetermined charging voltage for a predetermined time are repeated, and the full state is reached by checking the charging state. In the charging device for a secondary battery configured to stop charging when it is determined that there is a relaxation time between the above-described series of charging operations, a full-charge state check in the next series of charging operations is performed. Can be performed accurately, and the reliability is improved.
[0147]
According to the invention described in claim 5, charging is suspended from completion of a series of charging operations of the previous turn in each secondary battery to start of a series of charging operations of the next turn. Becomes the relaxation time, the electrode surface is stabilized, and the full charge state can be checked accurately in the next turn, and the reliability is improved.
Supplementally, during the charging of the secondary battery, an electrode reaction occurs on the surface of the electrode in contact with the electrolyte, and the process of this electrode reaction is the movement of the reactant from inside the electrolyte to the electrode surface, and the reaction between the reactant and the electrode. And the transfer of the product from the electrode surface to the inside of the electrolytic solution at the same time, and this transfer takes a considerable amount of time. Is checked, it may be detected as if it has reached a fully charged state due to ions in the moving process that are electrophoresing near the electrode surface. In order to prevent this erroneous detection, it is effective to provide a relaxation time. In the secondary battery charging apparatus according to the thirtieth aspect of the present invention, as a part of the charging cycle for each secondary battery, a reasonable and effective Has a relaxation time.
[0148]
Further, in the invention according to claim 6, in the charging device for a secondary battery according to any one of claims 1 to 5, a cooling unit for cooling a heat generating unit in the charging device is provided. By providing this, the heat generated by the heat-generating portion such as the heat-generating element is suppressed, heat transfer to the secondary battery is prevented, and excessive chemical reaction (oxidation-reduction reaction) inside the secondary battery is promoted. There is no illusion as if the user had generated heat from the secondary battery. As a result, the secondary battery is properly charged up to a full charge state, damage to the internal structure of the secondary battery can be prevented, and cycle life can be significantly improved.
[0149]
According to the seventh aspect of the present invention, the secondary battery can be easily taken out with one touch, and the convenience is improved.
[0150]
According to the invention described in claim 8, when the user operates the operation member, one side of the push-up member protrudes and retracts from the seat of the charging device, and the secondary battery can be easily taken out with one touch. , Convenience is improved.
[0151]
According to the ninth aspect of the present invention, when one longitudinal side of the secondary battery is pushed down, the one side sinks into the depression, and the other longitudinal side of the secondary battery rises, and the secondary battery rises. The support of both terminals of the secondary battery is released, and the secondary battery is taken out. In this way, the secondary battery can be easily taken out with one touch, and the convenience is improved.
[0152]
According to the tenth aspect, during the charging process, the type of the secondary battery and the like are automatically determined, and the secondary battery is fully charged without causing an excessive chemical reaction (oxidation-reduction reaction) inside the secondary battery. Charging can be properly performed up to the charging state. As a result, the cycle life can be significantly improved without damaging the internal structure of the secondary battery. In particular, since the main charging in this charging device is performed at a predetermined charging applied voltage value equal to or higher than the full charging equilibrium potential, a considerably large charging current flows, and the charging time can be reduced. In addition, since the charge state is checked at the full charge equilibrium potential, the battery can be charged to the full charge state accurately.
[0153]
Also, in the invention according to the eleventh aspect, during the charging process, the type of the secondary battery or the like is automatically determined, and the secondary battery is fully charged without causing an excessive chemical reaction (oxidation-reduction reaction) inside the secondary battery. Charging can be properly performed up to the charging state. As a result, the cycle life can be significantly improved without damaging the internal structure of the secondary battery. In particular, since the main charging in this charging device is performed at a predetermined charging applied voltage value equal to or higher than the full charging equilibrium potential, a considerably large charging current flows, and the charging time can be reduced. In addition, since the charge state is checked at the full charge equilibrium potential, the battery can be charged to the full charge state accurately.
[0154]
According to the twelfth aspect of the present invention, the battery voltage of the secondary battery taken out of the charging device is always higher than the recharge voltage value and is in a state suitable for use, so that the convenience can be improved.
Also, in this recharging, the recharge is properly performed until the battery is fully charged without causing an excessive chemical reaction (redox reaction), so that the internal structure of the secondary battery is not damaged and the cycle life is increased. And the charging time until full charging is shortened.
[0155]
Then, in the invention according to the thirteenth aspect, the state of charge of the secondary battery is checked, and a series of charging operations for charging at a predetermined charge voltage for a predetermined time are repeated, and the state of charge is checked to check that the secondary battery is fully charged. In the method of charging a secondary battery in which charging is stopped when it is determined that the battery has reached the charging time, a relaxation time is provided between the above-described series of charging operations to accurately check a full charge state in the next series of charging operations. Can be performed more reliably.
[0156]
Further, in the invention according to claim 14, charging is suspended from completion of a series of charging operations of the previous turn in each secondary battery to start of a series of charging operations of the next turn. Becomes the relaxation time, the electrode surface is stabilized, and the full charge state can be checked accurately in the next turn, and the reliability is improved.
Supplementally, during the charging of the secondary battery, an electrode reaction occurs on the surface of the electrode in contact with the electrolyte, and the process of this electrode reaction is the movement of the reactant from inside the electrolyte to the electrode surface, and the reaction between the reactant and the electrode. And the transfer of the product from the electrode surface to the inside of the electrolytic solution at the same time, and this transfer takes a considerable amount of time. Is checked, it may be detected as if it has reached a fully charged state due to ions in the moving process that are electrophoresing near the electrode surface. In order to prevent this erroneous detection, it is effective to provide a relaxation time. In the secondary battery charging apparatus according to the thirtieth aspect of the present invention, as a part of the charging cycle for each secondary battery, a reasonable and effective Has a relaxation time.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration of a charging device for a secondary battery 1 according to first to fourth embodiments.
FIG. 2 is a circuit diagram for measuring the electromotive force of the secondary battery 1.
FIG. 3 is a graph showing current-voltage characteristics for each charging rate of the secondary battery 1;
FIG. 4 is a flowchart illustrating charging control by the charging device for the secondary battery 1 according to the first embodiment.
FIG. 5 is a graph showing a time course of a battery terminal voltage, a charging current, and a check current of a nickel-hydrogen secondary battery.
FIG. 6 is a graph showing a battery terminal voltage, a charging current, and a check current of a nickel-cadmium secondary battery over time.
FIG. 7 is a flowchart illustrating charging control by the charging device for the secondary battery 1 according to the second embodiment.
FIG. 8 is a flowchart illustrating charging control by the charging device for the secondary battery 1 according to the second embodiment.
FIG. 9 is a flowchart illustrating charging control by the charging device for the secondary battery 1 according to the third embodiment.
FIG. 10 is a flowchart illustrating charging control by the charging device for the secondary battery 1 according to the third embodiment.
FIG. 11 is a plan view showing a configuration of a charging device 50 of the secondary batteries 1.1 according to a fifth embodiment.
FIG. 12 is a side sectional view showing a configuration of a charging device 50 of the secondary batteries 1.1 according to a sixth embodiment.
FIG. 13 is a rear cross-sectional view illustrating a configuration of an extraction unit of a charging device 50 of the secondary batteries 1, 7,... According to the seventh embodiment.
FIG. 14 is a side cross-sectional view showing a configuration of a take-out means of a charging device 50 of the secondary batteries 1,.
[Explanation of symbols]
1 Secondary battery
2 Power supply section
3 Current detector
4 Program / operation control unit
5 Voltage / current control unit
6 Charging voltage supply
9 Voltage detector

Claims (14)

Charging voltage supply means for supplying a charging voltage to the secondary battery, current detecting means for detecting a current value of a charging current supplied to the secondary battery, and voltage detecting means for detecting a voltage applied to the secondary battery A charging device for a secondary battery, comprising: a charging control device that controls charging of the secondary battery;
The charge control device,
For a secondary battery of n (n is a natural number of 2 or more) types, a full charge equilibrium potential and a charge applied voltage value for obtaining a peak value or substantially a peak value of a charge current, which exceeds the full charge equilibrium potential. Storage means for storing a predetermined charging applied voltage value that does not reach the irreversible chemical reaction area,
Switching means for switching a charging voltage supplied from the charging voltage supply means,
A current value detected by the current detection unit during application at the full charge equilibrium potential, and a current value determination unit that determines and compares a charge completion reference value set in advance,
A charging voltage value detected by the voltage detecting unit during charging at the predetermined charging applied voltage value, and a voltage value determining unit that compares the predetermined charging applied voltage value;
With
A charging device for a secondary battery, which controls charging of a secondary battery according to the following steps.
(Step 1) Assuming that a variable is k (k = 1, 2,..., N), k is initialized and k = 1.
(Step 2) The secondary battery set in the charging device is charged for a predetermined time at a k-th predetermined charging applied voltage value among predetermined charging applied voltage values of the n types of secondary batteries.
(Step 3) If k = n, jump to Step 6.
(Step 4) While the secondary battery is being charged at the k-th lowest predetermined charging applied voltage value for a predetermined time, the voltage value applied to the secondary battery is detected by the voltage detecting means.
(Step 5) The detected voltage value is compared by the voltage value determination means, and if the voltage value is larger than the k-th lowest predetermined charge application voltage value, 1 is added to k. Then, the process returns to the step 2 as a new k. On the other hand, if the voltage value is equal to or lower than the k-th lowest predetermined charge application voltage value, the process proceeds to the next step 6.
(Step 6) The applied voltage of the secondary battery is switched to the k-th lowest full-charge equilibrium potential among the full-charge equilibrium potentials of the n types of secondary batteries.
(Step 7) While the secondary battery is being applied at the k-th lowest full-charge equilibrium potential for a short time, the current value flowing through the secondary battery is detected by the current detecting means.
(Step 8) The detected current value is determined by the current value determining means. If the detected current value is larger than the charging completion reference value, the process returns to step 2 and the above flow is repeated. If the current value is equal to or less than the charging completion reference value, charging is stopped. Charging voltage supply means for supplying a charging voltage to the secondary battery, current detecting means for detecting a current value of a charging current supplied to the secondary battery, and voltage detecting means for detecting a voltage applied to the secondary battery A charging device for a secondary battery, comprising: a charging control device that controls charging of the secondary battery;
The charge control device,
For a secondary battery of n (n is a natural number of 2 or more) types, a full charge equilibrium potential and a charge applied voltage value for obtaining a peak value or substantially a peak value of a charge current, which exceeds the full charge equilibrium potential. Storage means for storing a predetermined charging applied voltage value that does not reach the irreversible chemical reaction area,
Switching means for switching a charging voltage supplied from the charging voltage supply means,
A current value detected by the current detection unit during application at the full charge equilibrium potential, and a current value determination unit that determines and compares a charge completion reference value set in advance,
The charging voltage value detected by the voltage detecting means during the charging at the predetermined charging applied voltage value, and the charging voltage value detected by the voltage detecting means during the previous charging at the predetermined charging applied voltage value Voltage difference determining means for determining whether the difference is within a predetermined range set in advance,
With
A charging device for a secondary battery, which controls charging of a secondary battery according to the following steps.
(Step 1) Assuming that a variable is k (k = 1, 2,..., N), k is initialized and k = 1.
(Step 2) The secondary battery set in the charging device is charged for a predetermined time at a k-th predetermined charging applied voltage value among predetermined charging applied voltage values of the n types of secondary batteries.
(Step 3) If k = n, jump to Step 6.
(Step 4) While the secondary battery is being charged at the k-th lowest predetermined charging applied voltage value for a predetermined time, the voltage value applied to the secondary battery is detected by the voltage detecting means.
(Step 5) The voltage difference detected by the voltage difference determination means during the current charging at the k-th predetermined charging applied voltage value, and the k-th predetermined charging applied voltage value at the previous time. If the difference from the voltage value detected during charging is within a predetermined range, the process proceeds to the next step 5, while if the difference exceeds a predetermined range, 1 is added to k. And returns to step 2 as a new k. However, when the current voltage value is detected for the first time, the process directly proceeds to the next step 6.
(Step 6) The applied voltage of the secondary battery is switched to the k-th lowest full-charge equilibrium potential among the full-charge equilibrium potentials of the n types of secondary batteries.
(Step 7) While the secondary battery is being applied at the k-th lowest full-charge equilibrium potential for a short time, the current value flowing through the secondary battery is detected by the current detecting means.
(Step 8) The detected current value is determined by the current value determining means. If the detected current value is larger than the charging completion reference value, the process returns to step 2 and the above flow is repeated. If the current value is equal to or less than the charging completion reference value, charging is stopped. Charging voltage supply means for supplying a charging voltage to the secondary battery,
Voltage detection means for detecting the battery voltage of the secondary battery,
Battery voltage value of the secondary battery after completion of charging detected by the voltage detection device, and a determination unit for comparing and determining a recharge voltage value lower than a full charge equilibrium potential,
With
When the battery voltage value is equal to or less than the recharge voltage value in the determination by the determination means, a charging voltage is supplied by the charging voltage supply means to perform recharging. Rechargeable battery charger. The charging state of the secondary battery is checked, a series of charging operations for charging at a predetermined charging voltage for a predetermined time are repeated, and the charging is stopped when it is determined that the charging state has reached a fully charged state. The charging device for a secondary battery, wherein a relaxation time is provided between the series of charging operations. A charging device for charging a plurality of secondary batteries, wherein after checking the state of charge of the secondary batteries, a series of charging operations for charging at a predetermined charging voltage for a predetermined time are alternately performed for each uncharged secondary battery. Then, this is defined as one turn, a plurality of rechargeable batteries are charged while repeating the turn, and charging is stopped from the rechargeable battery which is determined to have reached a fully charged state by checking the state of charge. In the secondary battery charger, the relaxation time is a time period between completion of a series of charging operations in a previous turn and start of a series of charging operations in a next turn in each secondary battery. The charging device for a secondary battery according to claim 4, wherein: The charging device for a secondary battery according to any one of claims 1 to 5,
A charging device for a secondary battery, comprising cooling means for cooling a heat generating portion in the charging device. A charging device for charging a secondary battery, comprising: an extraction means for removing the secondary battery set in a seat of the charging device with a single touch. The take-out means includes an operation member that is pressed down by a user, a push-up member that pushes up the secondary battery set in the seat, a pivot shaft that pivotally supports the push member, and an attachment member that is attached to the pivot shaft. Biasing means for biasing the push-up member in a direction opposite to the push-up direction,
The rechargeable battery charging device according to claim 7, wherein one side of the push-up member is protruded and retracted from the seat by operation of the operation member. The charging device for a secondary battery according to claim 8, wherein the removal unit is configured by depressing one longitudinal side of the seat portion. In the method of controlling the charge of the secondary battery,
n (n is a natural number of 2 or more) types of secondary batteries,
Full charge equilibrium potential,
A predetermined applied voltage value that is a charging applied voltage value that obtains a peak value or a substantially peak value of the charging current, and that exceeds the full charge equilibrium potential but does not reach the irreversible chemical reaction region;
Is stored in the storage means in advance,
A method for charging a secondary battery, comprising charging the secondary battery according to the following steps.
(Step 1) Assuming that a variable is k (k = 1, 2,..., N), k is initialized and k = 1.
(Step 2) The secondary battery is charged for a predetermined period of time at a k-th predetermined charging application voltage value among predetermined charging application voltage values of n types of secondary batteries.
(Step 3) If k = n, jump to Step 6.
(Step 4) The voltage value applied to the secondary battery is detected while the secondary battery is being charged at the k-th lowest predetermined applied voltage value for a predetermined time.
(Step 5) If the detected voltage value is larger than the k-th lowest predetermined charging applied voltage value, a value obtained by adding 1 to the k is returned as a new k and the process returns to the step 2; If the detected voltage value is equal to or lower than the k-th lowest predetermined charge application voltage value, the process proceeds to the next step 6.
(Step 6) The applied voltage of the secondary battery is switched to the k-th lowest full-charge equilibrium potential among the full-charge equilibrium potentials of the n types of secondary batteries.
(Step 7) A current value flowing through the secondary battery is detected while the secondary battery is applied at the k-th lowest full charge equilibrium potential for a short time.
(Step 8) If the detected current value is larger than the charge completion reference value, the flow returns to the step 2 and the above flow is repeated. If the detected current value is equal to or less than the charge completion reference value, Stop charging. In the method of controlling the charge of the secondary battery,
n (n is a natural number of 2 or more) types of secondary batteries,
Full charge equilibrium potential,
A predetermined applied voltage value that is a charging applied voltage value that obtains a peak value or a substantially peak value of the charging current, and that exceeds the full charge equilibrium potential but does not reach the irreversible chemical reaction region;
Is stored in the storage means in advance,
A method for charging a secondary battery, comprising charging the secondary battery according to the following steps.
(Step 1) Assuming that a variable is k (k = 1, 2,..., N), k is initialized and k = 1.
(Step 2) The secondary battery is charged for a predetermined period of time at a k-th predetermined charging application voltage value among predetermined charging application voltage values of n types of secondary batteries.
(Step 3) If k = n, jump to Step 6.
(Step 4) The voltage value applied to the secondary battery is detected while the secondary battery is being charged at the k-th lowest predetermined applied voltage value for a predetermined time.
(Step 5) The difference between the voltage value detected during charging at the k-th predetermined charging applied voltage value this time and the k-th predetermined charging applied voltage value at the previous time. If the difference from the detected voltage value is within the predetermined range, the process proceeds to the next step 6. On the other hand, if the difference exceeds the predetermined range, a value obtained by adding 1 to k is newly added. Then, the process returns to step 2 as n. However, when the current voltage value is detected for the first time, the process directly proceeds to the next step 6.
(Step 6) The applied voltage of the secondary battery is switched to the k-th lowest full-charge equilibrium potential among the full-charge equilibrium potentials of the n types of secondary batteries.
(Step 7) A current value flowing through the secondary battery is detected while the secondary battery is applied at the k-th lowest full charge equilibrium potential for a short time.
(Step 8) If the detected current value is larger than the charge completion reference value, the flow returns to the step 2 and the above flow is repeated. If the detected current value is equal to or less than the charge completion reference value, Stop charging. In the method of charging a secondary battery,
Monitoring the battery voltage value of the secondary battery after the completion of charging, and performing recharging when the battery voltage value becomes equal to or lower than a recharge voltage value lower than a full charge equilibrium potential. How to charge the battery. The charging state of the secondary battery is checked, a series of charging operations for charging at a predetermined charging voltage for a predetermined time are repeated, and the charging is stopped when it is determined that the charging state has reached a fully charged state. A method for charging a secondary battery, wherein a relaxation time is provided between the series of charging operations. A charging method for charging a plurality of secondary batteries, wherein after checking the state of charge of the secondary batteries, a series of charging operations for charging for a predetermined time at a predetermined charging voltage are alternately performed for each uncharged secondary battery. This is defined as one turn, and a plurality of rechargeable batteries are charged while repeating the turn, and charging is stopped from the rechargeable batteries that are determined to have reached the fully charged state by the check of the state of charge. In the charging method, the relaxation time is a time period between completion of a series of charging operations in a previous turn and start of a series of charging operations in a next turn in each secondary battery. Item 14. The charging device for a secondary battery according to Item 13.

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