JP2009033795A

JP2009033795A - Charging equipment, and charge type electric instrument equipped with the charging equipment

Info

Publication number: JP2009033795A
Application number: JP2007192377A
Authority: JP
Inventors: Masatoshi Ito; 正俊伊藤; Toshiharu Ohashi; 敏治大橋; Masaaki Sakagami; 正昭阪上
Original assignee: Panasonic Electric Works Co Ltd
Current assignee: Panasonic Electric Works Co Ltd
Priority date: 2007-07-24
Filing date: 2007-07-24
Publication date: 2009-02-12

Abstract

<P>PROBLEM TO BE SOLVED: To provide charging equipment which can prevent and suppress the deterioration of a battery and the shortening of its life, by preventing and suppressing the overcharge in charging a secondary battery which has been fully charged or whose residual capacity is nearly in full charge. <P>SOLUTION: In the charging equipment provided with a power source 11 which supplies power to a secondary battery 21, a voltage measuring part 13 which detects the voltage of the secondary battery 21, a current detector 14 which detects a charge current supplied to the secondary battery 21, a residual capacity detector 17 which detects the residual capacity of the secondary battery 21, and a control unit 12 which performs the charge operation by the switching system from constant current charge to constant voltage charge by controlling the power source 11, the control unit 12 sets the charge current value in the constant current charge, based on the residual capacity of the secondary battery 21 detected by the residual capacity detector 17. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

本発明は、例えばリチウムイオン電池等の二次電池を充電する充電装置およびこの充電装置を備えた充電式電動器具セットに係り、特に、満充電または残容量が満充電状態に近い二次電池を充電する際の過充電を防止・抑制して、電池の劣化や短命化を防止・抑制し得る充電装置およびこの充電装置を備えた充電式電動器具セットに関する。 The present invention relates to a charging device for charging a secondary battery such as a lithium ion battery and a rechargeable electric appliance set provided with the charging device, and more particularly, to a secondary battery having a fully charged or remaining capacity close to a fully charged state. The present invention relates to a charging device that can prevent / suppress overcharging during charging and prevent / suppress battery deterioration and shortening of life, and a rechargeable electric appliance set including the charging device.

近年、電動工具や携帯機器などの電気機器の駆動電源として、リチウムイオン二次電池やニッケル水素二次電池などの種々の二次電池が汎用されている。このような二次電池では、過充電されると、電池パックが破損したり、電池寿命を縮めてしまうことになる。特にリチウムイオン二次電池において、過充電による悪影響が顕著である。二次電池の過充電を防止するためには、少ない充電電流でゆっくり充電し、二次電池の電圧が所定値に達したら充電を停止するようにすればよい。しかし、充電電流を少なくすると、充電時間が増大してしまう。 In recent years, various secondary batteries such as lithium ion secondary batteries and nickel metal hydride secondary batteries have been widely used as drive power sources for electric devices such as electric tools and portable devices. If such a secondary battery is overcharged, the battery pack may be damaged or the battery life may be shortened. Particularly in a lithium ion secondary battery, the adverse effects due to overcharging are significant. In order to prevent overcharging of the secondary battery, it is only necessary to slowly charge with a small charging current and stop charging when the voltage of the secondary battery reaches a predetermined value. However, if the charging current is reduced, the charging time increases.

そこで、図１１に示すように、充電開始直後から、一定の電流Ｉ１で急速充電を行い、ある程度二次電池の電圧が上昇してから所定の定電圧Ｖ１を二次電池に印加する定電圧充電に切り替え、その後二次電池の充電が進むと共に充電電流を減少させて、充電電流が所定値を下回ったら充電を停止させ、二次電池の過充電を防止するようにした充電装置が知られている（例えば、特許文献１参照）。
特開平１０−６６２７７号公報 Therefore, as shown in FIG. 11, constant voltage charging is performed in which a quick charge is performed with a constant current I1 immediately after the start of charging, and a predetermined constant voltage V1 is applied to the secondary battery after the voltage of the secondary battery rises to some extent. There is known a charging device that prevents the secondary battery from being overcharged by stopping the charging when the charging current falls below a predetermined value as the charging of the secondary battery proceeds and then the charging current is reduced. (For example, refer to Patent Document 1).
Japanese Patent Laid-Open No. 10-66277

このような定電流充電から定電圧充電への切り換え充電方式においては、充電開始直後の定電流充電では定電圧充電に比べて大きな電流で充電を行う。しかしながら、満充電の電池パックを充電する際には、充電開始前に所定の電圧に達しているため、充電開始直後に直ちに定電圧充電に移行して充電電流を制限するとしても、定電圧充電は段階的に充電電流を下げて行くため、直ちに充電を停止することができない。したがって、満充電の電池パックを充電すると過充電となってしまい、電池が破壊する、或いは電池が劣化するおそれがあった。 In such a switching charging method from constant current charging to constant voltage charging, charging is performed with a larger current in constant current charging immediately after the start of charging than in constant voltage charging. However, when charging a fully charged battery pack, the voltage has reached a predetermined voltage before starting charging, so even if the charging current is limited immediately after starting charging, Since the charging current is gradually reduced, charging cannot be stopped immediately. Therefore, when a fully charged battery pack is charged, the battery pack is overcharged and the battery may be destroyed or the battery may be deteriorated.

本発明は、上記従来の事情に鑑みてなされたものであって、満充電または残容量が満充電状態に近い二次電池を充電する際の過充電を防止・抑制して、電池の劣化や短命化を防止・抑制し得る充電装置およびこの充電装置を備えた充電式電動器具セットを提供することを目的としている。 The present invention has been made in view of the above-described conventional circumstances, and prevents or suppresses overcharge when charging a secondary battery whose full charge or remaining capacity is close to a fully charged state, It is an object of the present invention to provide a charging device capable of preventing and suppressing the shortening of life and a rechargeable electric appliance set including the charging device.

上記目的を達成するために、本発明に係る充電装置は、二次電池へ電力を供給する電源部と、前記二次電池の電圧を検出する電圧測定部と、前記二次電池へ供給される充電電流を検出する電流検出部と、前記二次電池の残容量を検出する残容量検出部と、前記電源部を制御して定電流充電から定電圧充電への切り換え方式により充電動作を行う制御部と、を備えた充電装置であって、前記制御部は、前記残容量検出部により検出された前記二次電池の残容量に基づき、前記定電流充電における充電電流値を設定することを第１の特徴とする。 In order to achieve the above object, a charging device according to the present invention is supplied to a power supply unit that supplies power to a secondary battery, a voltage measurement unit that detects a voltage of the secondary battery, and the secondary battery. Control for performing charging operation by switching from constant current charging to constant voltage charging by controlling a current detecting unit for detecting charging current, a remaining capacity detecting unit for detecting remaining capacity of the secondary battery, and the power source unit A charging device having a constant current charging based on a remaining capacity of the secondary battery detected by the remaining capacity detecting unit. One feature.

また、本発明に係る充電装置は、複数の電池セルを備えた電池パックと、前記電池パックに対して充電動作を行う充電器とを有し、定電流充電から定電圧充電への切り換え方式により充電動作を行う充電装置であって、前記電池パックは、前記複数の電池セルへの充電が完了した後の該複数の電池セルの放電履歴を記憶する記憶手段を有し、前記充電器は、前記複数の電池セルへ電力を供給する電源部と、前記複数の電池セルの電圧を検出する電圧測定部と、前記複数の電池セルへ供給される充電電流を検出する電流検出部と、前記電源部を制御して定電流充電から定電圧充電への切り換え方式により充電動作を行う制御部と、を有し、前記制御部は、前記定電流充電開始前に前記記憶手段の放電履歴を参照して、放電履歴が無いときには該充電を行わないことを第２の特徴とする。 The charging device according to the present invention includes a battery pack including a plurality of battery cells, and a charger that performs a charging operation on the battery pack, and is switched by a switching method from constant current charging to constant voltage charging. A charging device that performs a charging operation, wherein the battery pack includes storage means for storing discharge histories of the plurality of battery cells after the charging to the plurality of battery cells is completed, and the charger includes: A power supply unit that supplies power to the plurality of battery cells; a voltage measurement unit that detects voltages of the plurality of battery cells; a current detection unit that detects charging currents supplied to the plurality of battery cells; and the power supply And a control unit that performs a charging operation by switching from constant current charging to constant voltage charging, and the control unit refers to a discharge history of the storage unit before starting the constant current charging. When there is no discharge history, The second feature means no electricity.

また、本発明に係る充電装置は、前記制御部は、前記記憶手段の放電履歴に基づき前記複数の電池セルの放電量を求め、該複数の電池セルの放電量に基づき前記定電流充電における充電電流値を設定することを第３の特徴とする。 Further, in the charging device according to the present invention, the control unit obtains a discharge amount of the plurality of battery cells based on a discharge history of the storage unit, and charges in the constant current charging based on the discharge amount of the plurality of battery cells. Setting the current value is a third feature.

さらに、本発明に係る充電装置を備えた充電式電動器具セットは、複数の電池セルを備えた電池パックと、前記電池パックに対して充電動作を行う充電器とを有する充電装置と、前記電池パックから供給される電力を電力源として所定の動作を行う電気器具本体と、を備えた充電式電動器具セットであって、前記充電装置は、請求項２または請求項３の何れか１項に記載の充電装置であることを第４の特徴とする。 Furthermore, the rechargeable electric appliance set including the charging device according to the present invention includes a battery pack including a plurality of battery cells, a charger that performs a charging operation on the battery pack, and the battery. A rechargeable electric appliance set including an electric appliance main body that performs a predetermined operation using electric power supplied from a pack as an electric power source, wherein the charging device is according to any one of claims 2 and 3. The charging device described is a fourth feature.

本発明に係る第１の特徴の充電装置では、二次電池の残容量に基づき定電流充電における充電電流値が設定されるので、残容量が満充電状態に近い二次電池を充電する際に通常の充電電流よりも低い電流値から定電圧充電を開始することができ、過充電を防止・抑制することができ、結果として電池の劣化や短命化を防止・抑制することができる。 In the charging device of the first feature according to the present invention, since the charging current value in constant current charging is set based on the remaining capacity of the secondary battery, when charging the secondary battery whose remaining capacity is close to a fully charged state Constant voltage charging can be started from a current value lower than the normal charging current, overcharging can be prevented / suppressed, and as a result, deterioration and shortening of the battery can be prevented / suppressed.

また、本発明に係る第２の特徴の充電装置では、放電履歴が無いときには再充電を行わないので、満充電の二次電池を充電しようとしても充電カットされることとなり、過充電を防止することができ、結果として電池の劣化や短命化を防止・抑制することができる。 Further, in the charging device of the second feature according to the present invention, since recharging is not performed when there is no discharge history, charging is cut even if an attempt is made to charge a fully charged secondary battery, thereby preventing overcharging. As a result, deterioration and shortening of the battery life can be prevented / suppressed.

また、本発明に係る第３の特徴の充電装置では、二次電池の放電量に基づき定電流充電における充電電流値が設定されるので、放電量の少ない満充電状態に近い二次電池を充電する際に通常の充電電流よりも低い電流値から定電圧充電を開始することができ、過充電を防止・抑制することができ、結果として電池の劣化や短命化を防止・抑制することができる。 In the charging device of the third feature according to the present invention, since the charging current value in constant current charging is set based on the discharging amount of the secondary battery, the secondary battery that is close to the fully charged state with a small discharging amount is charged. When charging, constant voltage charging can be started from a current value lower than the normal charging current, overcharging can be prevented / suppressed, and as a result, deterioration and shortening of the battery can be prevented / suppressed. .

以下、本発明の充電装置およびこの充電装置を備えた充電式電動器具セットの実施例について、〔実施例１〕、〔実施例２〕の順に図面を参照して詳細に説明する。 Hereinafter, an embodiment of a charging device of the present invention and a rechargeable electric appliance set provided with the charging device will be described in detail in the order of [Embodiment 1] and [Embodiment 2] with reference to the drawings.

〔実施例１〕
図１は本発明の実施例１に係る充電装置の構成図である。同図において、本実施例の充電装置は、充電器１および電池パック２を含む構成である。 [Example 1]
FIG. 1 is a configuration diagram of a charging apparatus according to Embodiment 1 of the present invention. In the figure, the charging device of the present embodiment includes a charger 1 and a battery pack 2.

電池パック２は、電池セルＥ１〜Ｅｎが複数個直列に接続された二次電池２１と、各電池セルＥ１〜Ｅｎの電圧を、単段でまたは２〜３段纏めて測定する電圧判定回路２２と、充電器１の接続端子Ｔ１１〜Ｔ１３に対応する接続端子Ｔ２１〜Ｔ２３とを備えて構成される。電池セルＥ１〜Ｅｎは、リチウムイオン電池等から成り、複数の電池セルが並列に接続されて構成されてもよく、また単段構成の場合は、電圧判定回路２２の機能は充電器１側の電圧測定部１３で実現できるので、該電圧判定回路２２は省略されてもよい。なお、電圧判定回路２２は、各段の電池セルＥ１〜Ｅｎの電圧を測定し、何れかの電池セルが予め定める目標電圧Ｖ１に達すると過充電信号をアクティブのローレベルとし、達していないと該過充電信号を非アクティブのハイレベルとして、接続端子Ｔ２３，Ｔ１３および残容量検出部１７を介して制御部１２へ出力する。 The battery pack 2 includes a secondary battery 21 in which a plurality of battery cells E1 to En are connected in series, and a voltage determination circuit 22 that measures the voltage of each battery cell E1 to En in a single stage or in two to three stages. And connection terminals T21 to T23 corresponding to the connection terminals T11 to T13 of the charger 1. The battery cells E1 to En are composed of lithium ion batteries or the like, and may be configured by connecting a plurality of battery cells in parallel. In the case of a single stage configuration, the function of the voltage determination circuit 22 is the function of the charger 1 side. Since it can be realized by the voltage measurement unit 13, the voltage determination circuit 22 may be omitted. The voltage determination circuit 22 measures the voltages of the battery cells E1 to En at each stage, and when any of the battery cells reaches a predetermined target voltage V1, the overcharge signal is set to an active low level. The overcharge signal is set to an inactive high level and output to the control unit 12 via the connection terminals T23 and T13 and the remaining capacity detection unit 17.

一方、充電器１は、電圧検知部１３と、電流検出部１４と、定電流回路１５および定電圧回路１６を含む電源部１１と、制御部１２と、残容量検出部１７と、を備えた構成である。 On the other hand, the charger 1 includes a voltage detection unit 13, a current detection unit 14, a power supply unit 11 including a constant current circuit 15 and a constant voltage circuit 16, a control unit 12, and a remaining capacity detection unit 17. It is a configuration.

電源部１１は、例えばＡＣ−ＤＣコンバータとして構成された電源回路で、電源線を介して接続された商用電源３から供給された交流電圧を直流電圧に変換する。そして、電源部１１における正極側出力端子は、接続端子Ｔ１１，Ｔ２３を介して二次電池２１の正極端子に接続され、電源部１１における負極側出力端子は、電流検出部１４、接続端子Ｔ１２，Ｔ２２を介して二次電池２１の負極端子に接続されている。 The power supply unit 11 is a power supply circuit configured as an AC-DC converter, for example, and converts an AC voltage supplied from a commercial power supply 3 connected via a power supply line into a DC voltage. The positive output terminal in the power supply unit 11 is connected to the positive terminal of the secondary battery 21 via the connection terminals T11 and T23, and the negative output terminal in the power supply unit 11 is the current detection unit 14, the connection terminal T12, It is connected to the negative terminal of the secondary battery 21 via T22.

定電流回路１５は、制御部１２からの制御信号に応じて電源部１１から電池パック２へ供給される二次電池２１の充電電流を調整する。また、定電圧回路１６は、制御部１２からの制御信号に応じて電源部１１から電池パック２へ供給される二次電池２１の充電電圧を調整する。 The constant current circuit 15 adjusts the charging current of the secondary battery 21 supplied from the power supply unit 11 to the battery pack 2 in accordance with a control signal from the control unit 12. The constant voltage circuit 16 adjusts the charging voltage of the secondary battery 21 supplied from the power supply unit 11 to the battery pack 2 in accordance with a control signal from the control unit 12.

また、電圧検知部１３は、接続端子Ｔ１１，Ｔ１２間の電圧、即ち二次電池２１における端子電圧を検出する回路部で、例えば抵抗体を用いて構成されており、その抵抗体の電圧降下により生じた電圧を、電圧検知信号として制御部１２へ出力する。 Moreover, the voltage detection part 13 is a circuit part which detects the voltage between the connection terminals T11 and T12, ie, the terminal voltage in the secondary battery 21, and is comprised using a resistor, for example, and the voltage drop of the resistor The generated voltage is output to the control unit 12 as a voltage detection signal.

また、電流検出部１４は、電源部１１から接続端子Ｔ１２，Ｔ２２を介して二次電池２３へ供給される充電電流を検出する回路部で、例えばホール素子を用いた電流センサや抵抗体によって充電電流を電圧に変換することにより得られた電流検知信号を制御部１２へ出力する。 The current detection unit 14 is a circuit unit that detects a charging current supplied from the power supply unit 11 to the secondary battery 23 via the connection terminals T12 and T22. For example, the current detection unit 14 is charged by a current sensor or a resistor using a Hall element. A current detection signal obtained by converting the current into a voltage is output to the control unit 12.

また、制御部１２は、例えば所定の演算処理を実行するＣＰＵ（Central Processing Unit）と、所定の制御プログラムが記録された不揮発性の記憶素子であるＲＯＭ（Read Only Memory）と、データを一時的に記録する揮発性の記憶素子であるＲＡＭ（Random Access Memory）と、電圧検知信号および電流検知信号をデジタル値に変換するＡＤコンバータとを備えて構成され、ＲＯＭに記憶された制御プログラムを実行することにより、電源部１１（定電流回路１５および定電圧回路１６）へ制御信号を出力して二次電池２１の充電動作を制御する。また、充電動作には大まかに予備充電、定電流充電および定電圧充電があるが、これらの制御も行う。 The control unit 12 temporarily stores data, for example, a CPU (Central Processing Unit) that executes predetermined arithmetic processing, a ROM (Read Only Memory) that is a nonvolatile storage element in which a predetermined control program is recorded, and the like. A RAM (Random Access Memory) that is a volatile storage element to be recorded in the memory and an AD converter that converts the voltage detection signal and the current detection signal into digital values, and executes a control program stored in the ROM Thus, a control signal is output to the power supply unit 11 (constant current circuit 15 and constant voltage circuit 16) to control the charging operation of the secondary battery 21. The charging operation includes roughly preliminary charging, constant current charging, and constant voltage charging, and these controls are also performed.

さらに、残容量検出部１７は、電池パック２が充電器１に装着されたときに、電池パック２内の温度検出回路（図示せず）との間で通信可能に接続されるようになっており、温度検出回路から出力された電池温度情報に基づいて、二次電池２１の残容量を検出し、その検出信号を制御部１２に出力する。ここで、電池電圧は、一般的に、放電時間が長くなるほど略線形的に小さくなる特性を持つ。また、その電池電圧は、電池温度に影響を受け、電池温度が高くなるほど大きくなる。 Furthermore, when the battery pack 2 is attached to the charger 1, the remaining capacity detection unit 17 is connected so as to be communicable with a temperature detection circuit (not shown) in the battery pack 2. The remaining capacity of the secondary battery 21 is detected based on the battery temperature information output from the temperature detection circuit, and the detection signal is output to the control unit 12. Here, the battery voltage generally has a characteristic of decreasing linearly as the discharge time increases. In addition, the battery voltage is affected by the battery temperature and increases as the battery temperature increases.

残容量検出部１７では、電池温度および電池電圧と二次電池２１の残容量との関係をテーブル形式で或いは演算式として予め記憶しており、それらを用いて、電池パック２が充電器１に装着された時点の電池電圧と、その時点において温度検出回路から出力される電池温度情報が示す電池温度とに基づいて、二次電池２１の残容量を推定的に導出する。そして、残容量検出部１７により導出された二次電池２１の残容量を示す信号が制御部１２に出力される。また、制御部１２では、残容量検出部１７で導出された二次電池２１の残容量に基づき定電流充電における充電電流値を設定する。 In the remaining capacity detection unit 17, the relationship between the battery temperature and the battery voltage and the remaining capacity of the secondary battery 21 is stored in advance in a table format or as an arithmetic expression, and the battery pack 2 is stored in the charger 1 using them. Based on the battery voltage at the time of attachment and the battery temperature indicated by the battery temperature information output from the temperature detection circuit at that time, the remaining capacity of the secondary battery 21 is estimated. Then, a signal indicating the remaining capacity of the secondary battery 21 derived by the remaining capacity detection unit 17 is output to the control unit 12. Further, the control unit 12 sets a charging current value in constant current charging based on the remaining capacity of the secondary battery 21 derived by the remaining capacity detection unit 17.

次に、以上のように構成された電池パック２および充電器１が結合されたときに、制御部１２の制御の下に行われる充電動作について、図２、図３および図４を参照して詳細に説明する。ここで、図２は実施例１の充電動作を説明するフローチャートであり、図３は実施例１において充電開始直後に電池電圧が所定電圧Ｖ１を超えていない場合の充電動作を説明する説明図であり、図３（ａ）は動作状態の時間的推移を、図３（ｂ）は二次電池２１の電池電圧の時間的推移を、図３（ｃ）は充電電流の時間的推移をそれぞれ示す。また、図４は実施例１において充電開始直後に電池電圧が所定電圧Ｖ１を超えている場合の充電動作を説明する説明図であり、図４（ａ）は動作状態の時間的推移を、図４（ｂ）は二次電池２１の電池電圧の時間的推移を、図４（ｃ）は充電電流の時間的推移をそれぞれ示す。 Next, referring to FIGS. 2, 3, and 4, the charging operation performed under the control of the control unit 12 when the battery pack 2 and the charger 1 configured as described above are combined. This will be described in detail. Here, FIG. 2 is a flowchart for explaining the charging operation of the first embodiment, and FIG. 3 is an explanatory diagram for explaining the charging operation when the battery voltage does not exceed the predetermined voltage V1 immediately after the start of charging in the first embodiment. 3A shows a temporal transition of the operating state, FIG. 3B shows a temporal transition of the battery voltage of the secondary battery 21, and FIG. 3C shows a temporal transition of the charging current. . FIG. 4 is an explanatory diagram for explaining the charging operation when the battery voltage exceeds the predetermined voltage V1 immediately after the start of charging in the first embodiment. FIG. 4 (a) shows the temporal transition of the operating state. 4 (b) shows the time transition of the battery voltage of the secondary battery 21, and FIG. 4 (c) shows the time transition of the charging current.

図２において、まず、電源投入用プラグを介して商用電源３から充電器１に通電され（ステップＳ１０１）、電池パック２が挿入されて電池パック２および充電器１が結合されると（ステップＳ１０２）、充電器１は電池パック２への充電を開始する（ステップＳ１０３）。 In FIG. 2, first, the charger 1 is energized from the commercial power source 3 through the power-on plug (step S101), and when the battery pack 2 is inserted and the battery pack 2 and the charger 1 are coupled (step S102). ), The charger 1 starts charging the battery pack 2 (step S103).

定電流充電に先立って、まず所定期間二次電池２１（電池パック２）の電圧を検出し、二次電池２１（電池パック２）の電圧が所定電圧Ｖ１を超えているか否かを判断する（ステップＳ１０４）。所定電圧Ｖ１を超えている場合には、電池パック２が満充電であるとして、図４に示すように、すぐに充電カットして充電動作を完了する（ステップＳ１１１）。 Prior to the constant current charging, the voltage of the secondary battery 21 (battery pack 2) is first detected for a predetermined period, and it is determined whether or not the voltage of the secondary battery 21 (battery pack 2) exceeds the predetermined voltage V1 ( Step S104). When the voltage exceeds the predetermined voltage V1, it is determined that the battery pack 2 is fully charged, and as shown in FIG. 4, the charging is immediately cut and the charging operation is completed (step S111).

また、二次電池２１（電池パック２）の電圧が所定電圧Ｖ１を超えていない場合には、ステップＳ１０５に進んで所定期間残容量検出部１７により二次電池２１（電池パック２）の残容量の検出を行う。そして残容量検出部１７で検出された残容量に基づき定電流充電における充電電流値を設定する（ステップＳ１０６）。 If the voltage of the secondary battery 21 (battery pack 2) does not exceed the predetermined voltage V1, the process proceeds to step S105, where the remaining capacity of the secondary battery 21 (battery pack 2) is detected by the remaining capacity detector 17 for a predetermined period. Detection is performed. Then, based on the remaining capacity detected by the remaining capacity detector 17, a charging current value in constant current charging is set (step S106).

例えば、図３では、時刻Ｔ０から時刻Ｔ１の期間に、ステップＳ１０４からステップＳ１０６までの処理が行われるが、図３（ａ）に示すように、二次電池２１（電池パック２）の電圧が所定電圧Ｖ１を超えてはいないが、相対的に高い電圧のとき、二次電池２１（電池パック２）の残容量も相対的に大きく、定電流充電における充電電流値として、通常の充電電流Ｉ１よりも小さい充電電流Ｉ２が設定されることになる。 For example, in FIG. 3, the processing from step S104 to step S106 is performed in the period from time T0 to time T1, but as shown in FIG. 3A, the voltage of the secondary battery 21 (battery pack 2) is Although the predetermined voltage V1 is not exceeded, when the voltage is relatively high, the remaining capacity of the secondary battery 21 (battery pack 2) is also relatively large, and a normal charging current I1 is used as a charging current value in constant current charging. A smaller charging current I2 is set.

次に、設定された充電電流Ｉ２による定電流充電（ステップＳ１０７）を開始して、二次電池２１の電圧が電圧値Ｖ１まで上昇するまで（図３において時刻Ｔ１から時刻Ｔ２の期間）この定電流充電を行う（ステップＳ１０８）。 Next, constant current charging with the set charging current I2 (step S107) is started, and this constant is maintained until the voltage of the secondary battery 21 rises to the voltage value V1 (period from time T1 to time T2 in FIG. 3). Current charging is performed (step S108).

二次電池２１の電圧が電圧値Ｖ１に達すると、定電流充電（ステップＳ１０７）を完了し、次に、電圧値Ｖ１による定電圧充電を開始して、図３（ｃ）に示すように充電電流Ｉ２から予め定める減分ΔＩ２ずつ段階的に電流を下げて行く（ステップＳ１０９）。より具体的には、二次電池２１の電圧が電圧値Ｖ１以上になったとき、電池パック２の電圧判定回路２２から過充電信号が接続端子Ｔ２３，Ｔ１３および残容量検出部１７を介して制御部１２へ出力され、制御部１２では目標電流値をΔＩ２下げるように充電電流を制御する。そして、定電圧充電（ステップＳ１０９）は、充電電流が閾値電流Ｉｅｎｄまで低下したとき（ステップＳ１１０）に充電完了となる（ステップＳ１１１）。 When the voltage of the secondary battery 21 reaches the voltage value V1, the constant current charging (step S107) is completed, and then the constant voltage charging by the voltage value V1 is started, and charging is performed as shown in FIG. The current is decreased stepwise from the current I2 by a predetermined decrement ΔI2 (step S109). More specifically, when the voltage of the secondary battery 21 becomes equal to or higher than the voltage value V1, an overcharge signal is controlled from the voltage determination circuit 22 of the battery pack 2 via the connection terminals T23 and T13 and the remaining capacity detection unit 17. The control unit 12 controls the charging current so as to decrease the target current value by ΔI2. The constant voltage charging (step S109) is completed when the charging current decreases to the threshold current Iend (step S110) (step S111).

以上説明したように、本実施例の充電装置では、二次電池２１へ電力を供給する電源部１１と、二次電池２１の電圧を検出する電圧測定部１３と、二次電池２１へ供給される充電電流を検出する電流検出部１４と、二次電池２１の残容量を検出する残容量検出部１７と、電源部１１を制御して定電流充電から定電圧充電への切り換え方式により充電動作を行う制御部１２と、を備えた充電装置において、制御部１２は、残容量検出部１７により検出された二次電池２１の残容量に基づき、定電流充電における充電電流値を設定する。 As described above, in the charging device according to the present embodiment, the power supply unit 11 that supplies power to the secondary battery 21, the voltage measurement unit 13 that detects the voltage of the secondary battery 21, and the secondary battery 21 are supplied. The current detection unit 14 for detecting the charging current, the remaining capacity detection unit 17 for detecting the remaining capacity of the secondary battery 21, and the power source unit 11 to control the charging operation by switching from constant current charging to constant voltage charging. The control unit 12 sets a charging current value in the constant current charging based on the remaining capacity of the secondary battery 21 detected by the remaining capacity detecting unit 17.

このように、二次電池２１の残容量に基づき定電流充電における充電電流値が設定されるので、残容量が満充電状態に近い二次電池を充電する際に通常の充電電流よりも低い電流値から定電圧充電を開始することができ、過充電を防止・抑制することができ、結果として電池の劣化や短命化を防止・抑制することができる。 Thus, since the charging current value in the constant current charging is set based on the remaining capacity of the secondary battery 21, the remaining capacity is lower than the normal charging current when charging the secondary battery close to the fully charged state. The constant voltage charging can be started from the value, overcharging can be prevented / suppressed, and as a result, deterioration and shortening of the battery can be prevented / suppressed.

なお、図１に示す本実施例の構成では、残容量検出部１７を充電器１に備えて、電池電圧と温度検出回路から出力される電池温度情報が示す電池温度とに基づき二次電池２１の残容量を推定的に導出する構成としたが、電池パック２に、容量算出回路とメモリ（記憶手段）を備える構成としても良い。容量算出回路は、二次電池２１への充電電流および該二次電池２１の放電電流を検出し、それらの電流の積算値により電池パック２の残容量を算出する。またメモリは、電池パック２の残容量を充電毎に記憶する。 In the configuration of the present embodiment shown in FIG. 1, the remaining capacity detection unit 17 is provided in the charger 1, and the secondary battery 21 is based on the battery voltage and the battery temperature indicated by the battery temperature information output from the temperature detection circuit. However, the battery pack 2 may be provided with a capacity calculation circuit and a memory (storage means). The capacity calculation circuit detects the charging current to the secondary battery 21 and the discharging current of the secondary battery 21 and calculates the remaining capacity of the battery pack 2 from the integrated value of these currents. The memory stores the remaining capacity of the battery pack 2 for each charge.

この場合、充電器１の制御部１２では、メモリに記憶された残容量が比較的大きいときには定電流充電における目標充電電流を相対的に小さく設定する一方、メモリに記憶された残容量が比較的小さいときには目標充電電流を相対的に大きく設定する。このような変形構成によっても、過充電を防止・抑制して電池の劣化や短命化を防止・抑制することができる。 In this case, when the remaining capacity stored in the memory is relatively large, the control unit 12 of the charger 1 sets the target charging current in constant current charging to be relatively small, while the remaining capacity stored in the memory is relatively small. When it is small, the target charging current is set relatively large. Even with such a modified configuration, it is possible to prevent / suppress overcharge and prevent / suppress battery deterioration and shortening of life.

〔実施例２〕
次に、図５は本発明の実施例２に係る充電装置の構成図である。同図において、本実施例の充電装置は、充電器１０１および電池パック１０２を含む構成である。 [Example 2]
Next, FIG. 5 is a configuration diagram of a charging apparatus according to Embodiment 2 of the present invention. In the figure, the charging device of this embodiment includes a charger 101 and a battery pack 102.

電池パック１０２は、電池セルＥ１〜Ｅｎが複数個直列に接続された二次電池２１と、各電池セルＥ１〜Ｅｎの電圧を、単段でまたは２〜３段纏めて測定する電圧判定回路２２と、充電器１の接続端子Ｔ１１〜Ｔ１３に対応する接続端子Ｔ２１〜Ｔ２３とを備えて構成される。これらの詳細については実施例１と同様である。 The battery pack 102 includes a secondary battery 21 in which a plurality of battery cells E1 to En are connected in series, and a voltage determination circuit 22 that measures the voltages of the battery cells E1 to En in a single stage or in two or three stages. And connection terminals T21 to T23 corresponding to the connection terminals T11 to T13 of the charger 1. These details are the same as those in the first embodiment.

また、電池パック１０２は、二次電池２１（電池セルＥ１〜Ｅｎ）への充電が完了した後の該二次電池２１の放電履歴を記憶するメモリ（記憶手段）２３を備えている。このメモリ２３には、放電履歴として充電完了フラグと放電時の放電量が記憶される。充電完了フラグは二次電池２１（電池セルＥ１〜Ｅｎ）への充電完了後における放電の有無を示すフラグであり、充電器１０１による充電完了時に制御部１２によってハイレベルにセットされ、電池パック１０２を充電式電動器具セットの電気器具本体（後述する電動工具１０３等）に挿入した時に、該電気器具本体の制御部によってローレベルにリセットされる。また、放電量は、充電式電動器具セットの電気器具本体が電池パック１０２を使用した時に、該電気器具本体の制御部によって放電時間（使用時間）が書き込まれる。なお、メモリ２３の放電履歴は接続端子Ｔ２４，Ｔ１４を介して制御部１２によって読み出すことができる。 In addition, the battery pack 102 includes a memory (storage unit) 23 that stores a discharge history of the secondary battery 21 after charging of the secondary battery 21 (battery cells E1 to En) is completed. The memory 23 stores a charge completion flag and a discharge amount at the time of discharge as a discharge history. The charge completion flag is a flag indicating whether or not the secondary battery 21 (battery cells E1 to En) has been charged, and is set to a high level by the control unit 12 when charging by the charger 101 is completed. Is inserted into an electric appliance body (such as an electric tool 103 described later) of the rechargeable electric appliance set, the controller is reset to a low level. Moreover, when the electric appliance main body of the rechargeable electric appliance set uses the battery pack 102, the discharge time (use time) is written by the control unit of the electric appliance main body. The discharge history of the memory 23 can be read out by the control unit 12 via the connection terminals T24 and T14.

一方、充電器１０１は、電圧検知部１３と、電流検出部１４と、電源部１１（定電流回路１５および定電圧回路は図示せず）と、制御部１２と、残容量検出部１７と、を備えた構成である。なお、電源部１１、電圧検知部１３、電流検出部１４および制御部１２の具現方法および機能は実施例１と同様であり、説明を省略する。 On the other hand, the charger 101 includes a voltage detection unit 13, a current detection unit 14, a power supply unit 11 (a constant current circuit 15 and a constant voltage circuit are not shown), a control unit 12, a remaining capacity detection unit 17, It is the structure provided with. In addition, the implementation method and function of the power supply unit 11, the voltage detection unit 13, the current detection unit 14, and the control unit 12 are the same as those in the first embodiment, and the description thereof is omitted.

なお、制御部１２における実施例２に固有の特徴的機能は、定電流充電開始前にメモリ２３の放電履歴を参照して、放電履歴が無いときには該充電を行わない点、並びに、メモリ２３の放電履歴に基づき二次電池２１（電池セルＥ１〜Ｅｎ）の放電量を求め、該放電量に基づき定電流充電における充電電流値を設定する点である。 The characteristic function unique to the second embodiment in the control unit 12 is that the charging history is not referred to when there is no discharging history by referring to the discharging history of the memory 23 before starting the constant current charging. The discharge amount of the secondary battery 21 (battery cells E1 to En) is obtained based on the discharge history, and the charge current value in constant current charging is set based on the discharge amount.

次に、図５の充電装置を備えた充電式電動器具セットについて説明する。本実施例の充電式電動器具セットは、二次電池２１（電池セルＥ１〜Ｅｎ）を備えた電池パック１０２と、電池パック１０２に対して充電動作を行う充電器１０１とを有する充電装置と、電池パック１０２から供給される電力を電力源として所定の動作を行う電動工具（電気器具本体）１０３と、を備えたものである。 Next, a rechargeable electric appliance set provided with the charging device of FIG. 5 will be described. The rechargeable electric appliance set of the present embodiment includes a battery pack 102 including a secondary battery 21 (battery cells E1 to En) and a charger 101 that performs a charging operation on the battery pack 102; And a power tool (electric appliance body) 103 that performs a predetermined operation using the power supplied from the battery pack 102 as a power source.

図６は、電池パック１０２を電動工具１０３に装着したときの充電式電動器具セットの構成図である。電池パック１０２の構成については、図５と同等である。 FIG. 6 is a configuration diagram of a rechargeable electric appliance set when the battery pack 102 is attached to the electric tool 103. The configuration of the battery pack 102 is the same as that in FIG.

また、電動工具１０３は、モータ３１と、制御部３２と、使用者により操作されるスイッチＳＷ１と、制御部３２によりオン／オフ制御されるトランジスタＴｒ１と、電池パック１０２の接続端子Ｔ２１，Ｔ２３，Ｔ２４に対応する接続端子Ｔ３１，Ｔ３３，Ｔ３４とを備えて構成される。 Further, the electric tool 103 includes a motor 31, a control unit 32, a switch SW1 operated by a user, a transistor Tr1 that is on / off controlled by the control unit 32, and connection terminals T21, T23, Connection terminals T31, T33, and T34 corresponding to T24 are provided.

次に、以上のように構成された電池パック１０２および充電器１０１が結合されたときに、制御部１２の制御の下に行われる充電動作について、図７、図８、図９および図１０を参照して詳細に説明する。ここで、図７は実施例２の充電動作を説明するフローチャートであり、図８は実施例２において充電開始直後に電池電圧が所定電圧Ｖ１を超えていない場合の充電動作を説明する説明図であり、図８（ａ）は動作状態の時間的推移を、図３（８）は二次電池２１の電池電圧の時間的推移を、図８（ｃ）は充電電流の時間的推移をそれぞれ示す。また、図９は実施例２において充電完了後に放電されていない電池パックを充電する場合の充電動作を説明する説明図であり、図９（ａ）は動作状態の時間的推移を、図９（ｂ）は二次電池２１の電池電圧の時間的推移を、図９（ｃ）は充電電流の時間的推移を、図９（ｄ）は充電完了フラグの時間的推移をそれぞれ示す。さらに、図１０は実施例２において充電完了後の放電履歴を持つ電池パックを充電する場合の充電動作を説明する説明図であり、図１０（ａ）は動作状態の時間的推移を、図１０（ｂ）は二次電池２１の電池電圧の時間的推移を、図１０（ｃ）は充電電流の時間的推移を、図１０（ｄ）は充電完了フラグの時間的推移をそれぞれ示す。 Next, with respect to the charging operation performed under the control of the control unit 12 when the battery pack 102 and the charger 101 configured as described above are combined, FIG. 7, FIG. 8, FIG. 9 and FIG. Details will be described with reference to FIG. FIG. 7 is a flowchart for explaining the charging operation of the second embodiment. FIG. 8 is an explanatory diagram for explaining the charging operation when the battery voltage does not exceed the predetermined voltage V1 immediately after the start of charging in the second embodiment. 8A shows a temporal transition of the operating state, FIG. 3A shows a temporal transition of the battery voltage of the secondary battery 21, and FIG. 8C shows a temporal transition of the charging current. . FIG. 9 is an explanatory diagram for explaining a charging operation when charging a battery pack that has not been discharged after completion of charging in the second embodiment. FIG. 9A shows a temporal transition of the operating state, and FIG. FIG. 9C shows the time transition of the battery voltage of the secondary battery 21, FIG. 9C shows the time transition of the charging current, and FIG. 9D shows the time transition of the charge completion flag. Further, FIG. 10 is an explanatory diagram for explaining a charging operation when charging a battery pack having a discharge history after completion of charging in the second embodiment, and FIG. 10 (a) shows a temporal transition of the operating state. (B) shows the time transition of the battery voltage of the secondary battery 21, FIG. 10 (c) shows the time transition of the charging current, and FIG. 10 (d) shows the time transition of the charge completion flag.

図７において、まず、電源投入用プラグを介して商用電源３から充電器１０１に通電され（ステップＳ２０１）、電池パック１０２が挿入されて電池パック１０２および充電器１０１が結合されると（ステップＳ２０２）、充電器１０１は電池パック１０２への充電を開始する（ステップＳ２０３）。 In FIG. 7, first, the charger 101 is energized from the commercial power source 3 through the power-on plug (step S201), and when the battery pack 102 is inserted and the battery pack 102 and the charger 101 are coupled (step S202). ), The charger 101 starts charging the battery pack 102 (step S203).

定電流充電に先立って、まず電池パック１０２のメモリ２３から放電履歴として充電完了フラグの値を充電完了信号により読み出し、前回の電池パック１０２への充電完了後に充電式電動器具セットの電気器具の使用による放電が有ったか否かを判断する（ステップＳ２０４）。放電が無い場合には、電池パック１０２が満充電状態であるとして、図９に示すように、すぐに充電カットして充電動作を完了する（ステップＳ２１１）。 Prior to the constant current charging, first, the value of the charging completion flag is read as a discharging history from the memory 23 of the battery pack 102 by the charging completion signal, and the use of the electric appliance of the rechargeable electric appliance set after the previous charging to the battery pack 102 is completed. It is determined whether or not there has been a discharge due to (step S204). If there is no discharge, the battery pack 102 is assumed to be fully charged, and as shown in FIG. 9, the charging is immediately cut and the charging operation is completed (step S211).

図９の例では、前回の電池パック１０２への充電完了時（時刻Ｔ２１）に、充電器１０１の制御部１２により電池パック１０２のメモリ２３内の充電完了フラグがセットされ、この時、充電完了信号はハイレベルとなる。その後、時刻Ｔ２３に、電池パック１０２を充電器１０１に挿入して充電を開始しようとするが、時刻Ｔ２１から時刻Ｔ２３の期間に電気器具の使用による放電は無く、充電完了信号がハイレベルのままであるので、再充電しようとしても充電カットされることになる。 In the example of FIG. 9, when the previous charging of the battery pack 102 is completed (time T21), the charging completion flag in the memory 23 of the battery pack 102 is set by the control unit 12 of the charger 101. At this time, the charging is completed. The signal goes high. Thereafter, at time T23, the battery pack 102 is inserted into the charger 101 to start charging, but there is no discharge due to the use of the appliance during the period from time T21 to time T23, and the charge completion signal remains at high level. Therefore, even if it tries to recharge, the charge is cut off.

また、ステップＳ２０４において放電が有った場合には、ステップＳ２０５に進む。図１０の例では、前回の電池パック１０２への充電完了時（時刻Ｔ３１）に、充電器１０１の制御部１２により電池パック１０２のメモリ２３内の充電完了フラグがセットされ、この時、充電完了信号はハイレベルとなる。その後、時刻Ｔ３２で例えば電動工具１０３による電池パック１０２の使用が有り、この時、電動工具１０３の制御部３２により電池パック１０２のメモリ２３内の充電完了フラグがリセットされ、充電完了信号はローレベルとなる。さらにその後、時刻Ｔ３３に、電池パック１０２を充電器１０１に挿入して充電を開始しようとする際には、充電完了信号がローレベルにリセットされているので、再充電できることになる。 If there is a discharge in step S204, the process proceeds to step S205. In the example of FIG. 10, when the previous charging of the battery pack 102 is completed (time T31), the charging completion flag in the memory 23 of the battery pack 102 is set by the control unit 12 of the charger 101. At this time, charging is completed. The signal goes high. Thereafter, at time T32, for example, the battery pack 102 is used by the electric tool 103. At this time, the control unit 32 of the electric tool 103 resets the charge completion flag in the memory 23 of the battery pack 102, and the charge completion signal is low level. It becomes. After that, when the battery pack 102 is inserted into the charger 101 and charging is started at time T33, the charging completion signal is reset to the low level, so that recharging can be performed.

また、時刻Ｔ３２から時刻Ｔ３３までの電動工具１０３による電池パック１０２の使用期間に、電動工具１０３の制御部３２によって電池パック１０２のメモリ２３内に放電時間（使用時間）が書き込まれており、時刻Ｔ３３の再充電開始時に、充電器１０１の制御部１２はこれを読み出し、二次電池２１の放電量を求め（ステップＳ２０５）、該放電量に基づき定電流充電における充電電流値を設定する（ステップＳ２０６）。 Further, during the usage period of the battery pack 102 by the electric tool 103 from time T32 to time T33, the discharge time (use time) is written in the memory 23 of the battery pack 102 by the control unit 32 of the electric tool 103, and the time At the start of recharging at T33, the control unit 12 of the charger 101 reads this, calculates the discharge amount of the secondary battery 21 (step S205), and sets the charge current value in constant current charging based on the discharge amount (step S205). S206).

例えば、図８では、時刻Ｔ０から時刻Ｔ１１の期間に、ステップＳ２０４からステップＳ２０６までの処理が行われるが、図８（ａ）に示すように、二次電池２１（電池パック２）の電圧が所定電圧Ｖ１を超えてはいないが、相対的に高い電圧のときには、二次電池２１（電池パック１０２）の放電量も相対的に小さいことから、定電流充電における充電電流値として、通常の充電電流Ｉ１よりも小さい充電電流Ｉ３が設定されることになる。 For example, in FIG. 8, the processing from step S204 to step S206 is performed in the period from time T0 to time T11. As shown in FIG. 8A, the voltage of the secondary battery 21 (battery pack 2) is Although the predetermined voltage V1 is not exceeded, when the voltage is relatively high, the discharge amount of the secondary battery 21 (battery pack 102) is also relatively small. A charging current I3 smaller than the current I1 is set.

次に、設定された充電電流Ｉ３による定電流充電（ステップＳ２０７）を開始して、二次電池２１の電圧が電圧値Ｖ１まで上昇するまで（図８において時刻Ｔ１１から時刻Ｔ１２の期間）この定電流充電を行う（ステップＳ２０８）。 Next, constant current charging with the set charging current I3 (step S207) is started, and this constant is maintained until the voltage of the secondary battery 21 rises to the voltage value V1 (period from time T11 to time T12 in FIG. 8). Current charging is performed (step S208).

二次電池２１の電圧が電圧値Ｖ１に達すると、定電流充電（ステップＳ２０７）を完了し、次に、電圧値Ｖ１による定電圧充電を開始して、図８（ｃ）に示すように充電電流Ｉ３から予め定める減分ΔＩ３ずつ段階的に電流を下げて行く（ステップＳ２０９）。より具体的には、二次電池２１の電圧が電圧値Ｖ１以上になったとき、電池パック１０２の電圧判定回路２２から過充電信号が接続端子Ｔ２３，Ｔ１３を介して制御部１２へ出力され、制御部１２では目標電流値をΔＩ３下げるように充電電流を制御する。そして、定電圧充電（ステップＳ２０９）は、充電電流が閾値電流Ｉｅｎｄまで低下したとき（ステップＳ２１０）に充電完了となる（ステップＳ２１１）。 When the voltage of the secondary battery 21 reaches the voltage value V1, the constant current charging (step S207) is completed, and then the constant voltage charging by the voltage value V1 is started, and charging is performed as shown in FIG. The current is decreased stepwise from the current I3 by a predetermined decrement ΔI3 (step S209). More specifically, when the voltage of the secondary battery 21 becomes equal to or higher than the voltage value V1, an overcharge signal is output from the voltage determination circuit 22 of the battery pack 102 to the control unit 12 via the connection terminals T23 and T13. The control unit 12 controls the charging current so as to lower the target current value by ΔI3. The constant voltage charging (step S209) is completed when the charging current is reduced to the threshold current Iend (step S210) (step S211).

以上説明したように、本実施例の充電装置では、複数の電池セルＥ１〜Ｅｎ（二次電池２１）を備えた電池パック１０２と、電池パック１０２に対して充電動作を行う充電器１０１とを有し、定電流充電から定電圧充電への切り換え方式により充電動作を行う充電装置であって、電池パック１０２は、複数の電池セルＥ１〜Ｅｎへの充電が完了した後の該複数の電池セルＥ１〜Ｅｎの放電履歴を記憶するメモリ（記憶手段）２３を有し、充電器１０１は、複数の電池セルＥ１〜Ｅｎへ電力を供給する電源部１１と、複数の電池セルＥ１〜Ｅｎの電圧を検出する電圧測定部１３（２２）と、複数の電池セルＥ１〜Ｅｎへ供給される充電電流を検出する電流検出部１４と、電源部１１を制御して定電流充電から定電圧充電への切り換え方式により充電動作を行う制御部１２と、を有し、制御部１２は、定電流充電開始前にメモリ２３の放電履歴を参照して、放電履歴が無いときには該充電を行わない。 As described above, in the charging device according to the present embodiment, the battery pack 102 including the plurality of battery cells E1 to En (secondary batteries 21) and the charger 101 that performs the charging operation on the battery pack 102 are provided. A charging device that performs charging operation according to a switching method from constant current charging to constant voltage charging, wherein the battery pack 102 has the plurality of battery cells after the charging to the plurality of battery cells E1 to En is completed. The memory 101 (memory | storage means) 23 which memorize | stores the discharge history of E1-En, the charger 101 is the power supply part 11 which supplies electric power to several battery cell E1-En, and the voltage of several battery cell E1-En The voltage measuring unit 13 (22) for detecting the current, the current detecting unit 14 for detecting the charging current supplied to the plurality of battery cells E1 to En, and the power source unit 11 to control the constant current charging to the constant voltage charging. Depending on the switching method Includes a control unit 12 for the electric operation, the control unit 12 refers to the discharge history of the constant current charging started before the memory 23 does not perform the charging when discharging history no.

このように、放電履歴が無いときには再充電を行わないので、満充電の二次電池を充電しようとしても充電カットされることとなり、過充電を防止することができ、結果として電池の劣化や短命化を防止・抑制することができる。 In this way, since recharging is not performed when there is no discharge history, charging is cut even when trying to charge a fully charged secondary battery, overcharging can be prevented, resulting in deterioration of the battery and short life. Can be prevented / suppressed.

また、本実施例の充電装置では、制御部１２は、メモリ２３の放電履歴に基づき複数の電池セルＥ１〜Ｅｎの放電量を求め、該複数の電池セルの放電量に基づき定電流充電における充電電流値を設定する。 Moreover, in the charging device of the present embodiment, the control unit 12 obtains the discharge amounts of the plurality of battery cells E1 to En based on the discharge history of the memory 23, and charges in constant current charging based on the discharge amounts of the plurality of battery cells. Set the current value.

このように、二次電池２１の放電量に基づき定電流充電における充電電流値が設定されるので、放電量の少ない満充電状態に近い二次電池を充電する際に通常の充電電流よりも低い電流値から定電圧充電を開始することができ、過充電を防止・抑制することができ、結果として電池の劣化や短命化を防止・抑制することができる。 Thus, since the charging current value in constant current charging is set based on the discharge amount of the secondary battery 21, it is lower than the normal charging current when charging a secondary battery close to a fully charged state with a small discharge amount. Constant voltage charging can be started from the current value, overcharging can be prevented / suppressed, and as a result, deterioration and shortening of the battery can be prevented / suppressed.

なお、以上説明した実施例２では、メモリ２３に放電履歴として記憶される放電時の放電量を書き込む構成として、充電式電動器具セットの電気器具本体（制御部３２）により放電時間（使用時間）を書き込む構成としたが、電池パック１０２に、放電量算出回路を備える構成としても良い。この場合、放電量算出回路は、二次電池２１の放電電流を検出し、その積算値により電池パック２の放電量を算出する。 In the second embodiment described above, the discharge amount (use time) is determined by the electric appliance main body (control unit 32) of the rechargeable electric appliance set as a configuration in which the discharge amount at the time of discharge stored in the memory 23 as the discharge history is written. However, the battery pack 102 may include a discharge amount calculation circuit. In this case, the discharge amount calculation circuit detects the discharge current of the secondary battery 21 and calculates the discharge amount of the battery pack 2 based on the integrated value.

本発明の実施例１に係る充電装置の構成図である。It is a block diagram of the charging device which concerns on Example 1 of this invention. 実施例１の充電動作を説明するフローチャートである。3 is a flowchart illustrating a charging operation according to the first embodiment. 実施例１において充電開始直後に電池電圧が所定電圧Ｖ１を超えていない場合の充電動作を説明する説明図であり、図３（ａ）は動作状態の時間的推移を、図３（ｂ）は二次電池２１の電池電圧の時間的推移を、図３（ｃ）は充電電流の時間的推移をそれぞれ示す。FIG. 3 is an explanatory diagram for explaining a charging operation when the battery voltage does not exceed a predetermined voltage V1 immediately after the start of charging in Example 1, FIG. 3 (a) shows a temporal transition of the operating state, and FIG. The time transition of the battery voltage of the secondary battery 21 is shown in FIG. 3C, and the time transition of the charging current is shown. 実施例１において充電開始直後に電池電圧が所定電圧Ｖ１を超えている場合の充電動作を説明する説明図であり、図４（ａ）は動作状態の時間的推移を、図４（ｂ）は二次電池２１の電池電圧の時間的推移を、図４（ｃ）は充電電流の時間的推移をそれぞれ示す。In Example 1, it is explanatory drawing explaining the charging operation in case battery voltage exceeds predetermined voltage V1 immediately after charge start, FIG.4 (a) is a time transition of an operating state, FIG.4 (b) is FIG. FIG. 4C shows the time transition of the battery voltage of the secondary battery 21, and FIG. 4C shows the time transition of the charging current. 本発明の実施例２に係る充電装置の構成図である。It is a block diagram of the charging device which concerns on Example 2 of this invention. 電池パック１０２を電動工具１０３に装着したときの充電式電動器具セットの構成図である。It is a block diagram of a rechargeable electric appliance set when the battery pack is mounted on the electric tool. 実施例２の充電動作を説明するフローチャートである。6 is a flowchart illustrating a charging operation according to the second embodiment. 実施例２において充電開始直後に電池電圧が所定電圧Ｖ１を超えていない場合の充電動作を説明する説明図であり、図８（ａ）は動作状態の時間的推移を、図３（８）は二次電池２１の電池電圧の時間的推移を、図８（ｃ）は充電電流の時間的推移をそれぞれ示す。In Example 2, it is explanatory drawing explaining the charging operation in case the battery voltage does not exceed the predetermined voltage V1 immediately after charge start, FIG. 8 (a) is a time transition of an operation state, FIG.3 (8) is FIG. FIG. 8C shows the time transition of the battery voltage of the secondary battery 21, and FIG. 8C shows the time transition of the charging current. 実施例２において充電完了後に放電されていない電池パックを充電する場合の充電動作を説明する説明図であり、図９（ａ）は動作状態の時間的推移を、図９（ｂ）は二次電池２１の電池電圧の時間的推移を、図９（ｃ）は充電電流の時間的推移を、図９（ｄ）は充電完了フラグの時間的推移をそれぞれ示す。9A and 9B are explanatory diagrams for explaining a charging operation when charging a battery pack that has not been discharged after completion of charging in FIG. 9, FIG. 9A shows a temporal transition of the operating state, and FIG. FIG. 9 (c) shows the time transition of the charging current, and FIG. 9 (d) shows the time transition of the charging completion flag. 実施例２において充電完了後の放電履歴を持つ電池パックを充電する場合の充電動作を説明する説明図であり、図１０（ａ）は動作状態の時間的推移を、図１０（ｂ）は二次電池２１の電池電圧の時間的推移を、図１０（ｃ）は充電電流の時間的推移を、図１０（ｄ）は充電完了フラグの時間的推移をそれぞれ示す。FIG. 10A is an explanatory diagram for explaining a charging operation when charging a battery pack having a discharge history after completion of charging in Example 2, FIG. 10A shows a temporal transition of the operating state, and FIG. FIG. 10C shows the time transition of the charging current, and FIG. 10D shows the time transition of the charging completion flag. 従来の充電動作を説明する説明図である。It is explanatory drawing explaining the conventional charging operation.

Explanation of symbols

１，１０１充電器
２，１０２電池パック
３商用電源
１１電源部
１２制御部
１３電圧測定部
１４電流検出部
１５定電流回路
１６定電圧回路
１７残容量検出部
２１二次電池
２２電圧判定回路
２３メモリ（記憶手段）
３２制御部
１０３電動工具（電気器具本体）
Ｅ１〜Ｅｎ電池セル
Ｔ１１〜Ｔ１４，Ｔ２１〜Ｔ２４，Ｔ３１〜Ｔ３４接続端子
ＳＷ１スイッチ
Ｔｒ１トランジスタ DESCRIPTION OF SYMBOLS 1,101 Charger 2,102 Battery pack 3 Commercial power supply 11 Power supply part 12 Control part 13 Voltage measurement part 14 Current detection part 15 Constant current circuit 16 Constant voltage circuit 17 Remaining capacity detection part 21 Secondary battery 22 Voltage determination circuit 23 Memory (Memory means)
32 Control Unit 103 Electric Tool (Electric Appliance Body)
E1 to En battery cells T11 to T14, T21 to T24, T31 to T34 Connection terminal SW1 switch Tr1 transistor

Claims

A power supply for supplying power to the secondary battery;
A voltage measuring unit for detecting a voltage of the secondary battery;
A current detector for detecting a charging current supplied to the secondary battery;
A remaining capacity detector for detecting a remaining capacity of the secondary battery;
A control unit that controls the power supply unit to perform a charging operation by a switching method from constant current charging to constant voltage charging, and a charging device comprising:
The said control part sets the charging current value in the said constant current charge based on the remaining capacity of the said secondary battery detected by the said remaining capacity detection part, The charging device characterized by the above-mentioned.

A battery pack having a plurality of battery cells, a charger that performs a charging operation on the battery pack, and a charging device that performs a charging operation by switching from constant current charging to constant voltage charging,
The battery pack has storage means for storing discharge histories of the plurality of battery cells after the charging to the plurality of battery cells is completed,
The charger includes a power supply unit that supplies power to the plurality of battery cells, a voltage measurement unit that detects voltages of the plurality of battery cells, and a current detection that detects charging currents supplied to the plurality of battery cells. And a control unit that controls the power supply unit and performs a charging operation by a switching method from constant current charging to constant voltage charging,
The controller refers to the discharge history of the storage means before the start of the constant current charge, and does not perform the charge when there is no discharge history.

The control unit obtains a discharge amount of the plurality of battery cells based on a discharge history of the storage means, and sets a charge current value in the constant current charging based on the discharge amount of the plurality of battery cells. The charging device according to claim 2.

A battery pack having a plurality of battery cells, a charging device having a charger that performs a charging operation on the battery pack, and an electric appliance body that performs a predetermined operation using power supplied from the battery pack as a power source A rechargeable electric appliance set comprising:
The charging device is the charging device according to any one of claims 2 and 3, wherein the charging device is a rechargeable electric appliance set.