Battery packs and power tools

Abstract

To provide a battery pack improved in applicability and used for a power tool, and a power tool having the same.SOLUTION: A battery pack 1 used for a power tool includes: a power storage unit 2 including a lithium ion battery that is a secondary battery 21; and positive electrode terminals 31, 33 and a negative electrode terminal 32 that are power supply terminals for supplying power to a main body of the power tool. The power storage unit includes an all-solid battery, as a secondary battery, having a solid electrolyte separating a positive electrode and a negative electrode as a separator, and comprises a signal output terminal 73 corresponding to a temperature detection terminal 75 for outputting a temperature of the power storage unit. The temperature detection terminal is a terminal for receiving a signal related to the temperature detected from the secondary battery from the secondary battery.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates generally to a battery pack and a power tool, and more particularly to a battery pack for use in a power tool and a power tool including the battery pack. [Background technology]

[0002] Patent Document 1 discloses a battery pack capable of detecting an abnormal state.

[0003] The battery pack of Patent Document 1 includes a battery pack, a processing unit, and a determination unit. The battery pack includes a plurality of secondary batteries. The processing unit detects the voltage of each of the plurality of secondary batteries and outputs a first signal when the detected voltage of at least one of the plurality of secondary batteries is lower than a first threshold. The processing unit outputs a second signal when the detected voltage of at least one of the plurality of secondary batteries is higher than a second threshold that is higher than the first threshold. The determination unit determines an abnormal state when it acquires both the first signal and the second signal from the processing unit. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-79632 A Summary of the Invention [Problem to be solved by the invention]

[0005] Currently, lithium-ion batteries are widely used in battery packs, but they can be difficult to use depending on the usage environment, and further improvements in applicability are sometimes required.

[0006] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a battery pack and a power tool with improved applicability. [Means for solving the problem]

[0007] A battery pack according to one aspect of the present disclosure is used in an electric power tool. The battery pack includes a power storage unit, and a positive terminal and a negative terminal, which are power supply terminals. The power storage unit includes a secondary battery. The battery pack supplies power to a main body of the electric power tool via the positive terminal and the negative terminal, which are power supply terminals. The power storage unit includes, as the secondary battery, an all-solid-state battery having a solid electrolyte as a separator that separates the positive electrode and the negative electrode. The power storage unit includes a signal output terminal corresponding to a temperature detection terminal that outputs the temperature of the power storage unit. The signal output from the signal output terminal includes a dummy signal corresponding to the temperature detection terminal.

[0008] An electric power tool according to one aspect of the present disclosure includes the battery pack and a main body to which the battery pack is detachably attached. Effect of the Invention

[0009] According to the present disclosure, it is possible to provide a battery pack and a power tool with improved applicability. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a block diagram of a battery pack used in a power tool according to one embodiment. [Diagram 2] FIG. 2 is a perspective view of a battery pack used in the power tool. [Diagram 3] FIG. 3 is a diagram for explaining a power tool including a battery pack used in the power tool of the above embodiment. [Figure 4] FIG. 4 is a block diagram of a battery pack used in a power tool according to one modified example. [Diagram 5] FIG. 5 is a block diagram of a battery pack used in a power tool according to a modified example different from that shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The embodiments and modifications described below are merely examples of the present disclosure, and the present disclosure is not limited to the embodiments and modifications. Various modifications other than these embodiments and modifications are possible according to the design, etc., as long as they do not deviate from the technical idea of ​​the present disclosure.

[0012] (Embodiment) Hereinafter, a battery pack 1 according to this embodiment will be described with reference to FIGS.

[0013] (1) Overview of power tools 3, the power tool 100 according to this embodiment includes a main body 50 and a battery pack 1. The main body 50 includes a drive unit 102, a drive transmission unit 103, a tool attachment unit 101, and a tool tip 40. The power tool 100 is a tool that drives the tool tip 40 by the driving force of the drive unit 102.

[0014] The driving unit 102 is a driving source that drives the tool bit 40. The driving unit 102 is, for example, a brushless motor.

[0015] The drive transmission unit 103 adjusts the output (driving force) of the drive unit 102 and outputs it to the output shaft. The output shaft is a part that is driven (e.g., rotated) by the driving force output from the drive transmission unit 103. The tool attachment unit 101 is fixed to the output shaft and is a part to which the tip tool 40 is detachably attached. The tip tool 40 (also called a bit) is, for example, a driver, a socket, or a drill. Of the various types of tip tools 40, a tip tool 40 appropriate for the purpose is attached to the tool attachment unit 101 and used.

[0016] The trigger volume 105 is an operation unit that accepts an operation for controlling the rotation of the drive unit 102. A user can switch the drive unit 102 on and off by pulling the trigger volume 105. In addition, the user can adjust the rotation speed of the output shaft, that is, the rotation speed of the drive unit 102, by the amount of operation of pulling the trigger volume 105.

[0017] In the power tool 100, the tool tip 40 is attached to the tool attachment portion 101. The rotation speed of the drive portion 102 is controlled by operating the trigger volume 105, and thereby the rotation speed of the tool tip 40 is controlled.

[0018] In the power tool 100 of the present embodiment, the tool attachment portion 101 allows the tool tip 40 to be replaced depending on the application, but the tool tip 40 does not need to be replaceable. For example, the power tool 100 may be a power tool that allows only a specific tool tip 40 to be used.

[0019] The battery pack 1 is used in the power tool 100. The battery pack 1 includes a power storage unit 2 and a positive terminal 31 and a negative terminal 32 that are power supply terminals. The power storage unit 2 includes a secondary battery 21. The battery pack 1 supplies power to a main body 50 of the power tool 100 via the positive terminal 31 and the negative terminal 32 that are power supply terminals. The power storage unit 2 includes, as the secondary battery 21, an all-solid-state battery 35 having a solid electrolyte as a separator that separates the positive electrode and the negative electrode. The power storage unit 2 includes a signal output terminal 73 that corresponds to a temperature detection terminal 75 that outputs the temperature of the power storage unit 2.

[0020] The battery pack 1 further includes a power storage unit 2, a thermistor 22, a communication connector 7, a processing unit 4, and a housing 9. As shown in Fig. 1, the battery pack 1 is detachably attached to a main body unit 50 of the power tool 100 via a battery pack attachment unit 106.

[0021] The power storage unit 2 includes, for example, one or more secondary batteries 21. In this embodiment, as shown in Fig. 1 and Fig. 3, the power storage unit 2 has five secondary batteries 21 connected in series. Although it is possible to use a lithium ion battery as the secondary battery 21, in this embodiment, an all-solid-state battery 35 is used. The all-solid-state battery 35 has a solid electrolyte as a separator that separates the positive electrode and the negative electrode.

[0022] The thermistor 22 measures the temperature of the all-solid-state battery 35. The thermistor 22 is, for example, a Negative Temperature Coefficient Thermistor (NTC thermistor). Note that the thermistor 22 is not an essential component of the battery pack 1 and can be omitted as appropriate.

[0023] The communication connector 7 is a connector used as an interface for communicating with the power tool 100 and the charger.

[0024] The processing unit 4, for example, detects the voltage of each of the secondary batteries 21, and when the detected voltage of at least one of the secondary batteries 21 is lower than a first threshold value, outputs a first signal to the power tool 100 via a first output terminal 71 among the multiple communication terminals 70.

[0025] The housing 9 accommodates the power storage unit 2 .

[0026] The communication connector 7, the processing section 4, and the housing 9 will be described in detail in "(2) Overall configuration of the battery pack" below.

[0027] (2) Overall configuration of the battery pack The battery pack 1 of this embodiment can be used as a power source for a device to which the battery pack 1 can be detached, such as a power tool 100. The battery pack 1 is charged by a charger to which the battery pack 1 can be detached.

[0028] The battery pack 1 includes a power storage unit 2 including a secondary battery 21, and a housing that accommodates the power storage unit 2 (see FIG. 2).

[0029] The power storage unit 2 includes a plurality of (five in this embodiment) secondary batteries 21. In the power storage unit 2, the secondary batteries 21 are connected in series. Each of the secondary batteries 21 constitutes a single cell of the power storage unit 2.

[0030] As shown in FIG. 2 , the housing 9 includes a body 90 and a cover 91 coupled to the body 90. The body 90 is box-shaped with the cover 91 side open. The body 90 houses the power storage unit 2. The cover 91 is box-shaped with the body 90 side open. The cover 91 includes a protruding portion 92 protruding from a surface 911 opposite to the body 90 side. The protruding portion 92 is in the shape of a flat rectangular parallelepiped. The body 90 is a synthetic resin molded product. The material of the body 90 is, for example, ABS resin. The body 90 has electrical insulation properties. The cover 91 is a synthetic resin molded product. The material of the cover 91 is, for example, ABS resin. The cover 91 has electrical insulation properties.

[0031] The protruding portion 92 has a first end 921 and a second end 922 in the longitudinal direction. In the battery pack 1, three insertion grooves 931, 933, and 932 are formed at the first end 921 of the protruding portion 92. A positive electrode terminal 31, a negative electrode terminal 32, and a positive electrode terminal 33 are connected to the three insertion grooves 931, 932, and 933, respectively. The negative electrode terminal 32 is connected to the negative electrode of the power storage unit 2. In the battery pack 1, the positive electrode terminal 31 and the negative electrode terminal 32 are used for discharging to the power tool 100. In the battery pack 1, the positive electrode terminal 33 and the negative electrode terminal 32 are used for charging from a charger. The positive electrode terminal 31, the negative electrode terminal 32, and the positive electrode terminal 33 are female connection terminals into which male connection terminals are inserted for connection. The battery pack 1 has three L-shaped hooks 941, 942, 943 provided on each of a pair of side surfaces 923 in the shorter direction of the protruding portion 92 as attachment portions to a device and a charger.

[0032] The battery pack 1 also includes a communication connector 7. The communication connector 7 is a connector used as an interface for communicating with the power tool 100 and the charger. The communication connector 7 includes a plurality of communication terminals 70 (see FIG. 1). Here, the communication connector 7 is used when communicating battery pack information with the power tool 100 and the charger. The communication connector 7 includes a plurality of communication terminals 70 for outputting the battery pack information. The battery pack information includes, for example, temperature information, rated temperature information, and the like. The temperature information is the temperature of the battery pack 1, and more specifically, the temperature of the power storage unit 2 in the housing 9. The rated voltage information is information related to the rated voltage of the battery pack 1, and in this embodiment, is information related to the rated voltage of the power storage unit 2.

[0033] As shown in FIG. 1, the battery pack 1 includes a power storage unit 2, a positive terminal 31, a negative terminal 32, a positive terminal 33, and a communication connector 7, as well as a processing unit 4, a determination unit 5, an information output unit 6, and a notification unit 8.

[0034] (3) Composition The secondary battery 21 in the power storage unit 2 of the battery pack 1 is formed of an all-solid-state battery 35. The all-solid-state battery 35 has a solid electrolyte as a separator that separates a positive electrode from a negative electrode. The rated voltage of the all-solid-state battery is, for example, 3.6 V. The rated voltage of the battery pack 1 is, for example, 18.0 V, and in this embodiment, five secondary batteries 21 are connected in series as shown in FIG. 1. The power storage unit 2 is accommodated in a housing 9.

[0035] The processing unit 4 detects the voltage of each of the secondary batteries 21, and outputs a first signal to the power tool 100 via a first output terminal 71 of the multiple communication terminals 70 when the detected voltage of at least one of the secondary batteries 21 is lower than a first threshold. Furthermore, the processing unit 4 outputs a second signal to the power tool 100 via a second output terminal 72 of the multiple communication terminals 70 when the detected voltage of the secondary batteries 21 other than the at least one secondary battery 21 is higher than a second threshold that is higher than the first threshold. The first threshold is a voltage value lower than the rated voltage of the secondary battery 21, for example, 2V. The second threshold is a voltage value higher than the rated voltage of the secondary battery 21, for example, 4V.

[0036] The processing unit 4 includes a battery monitoring unit 41 , a discharge control unit 42 , and a charge control unit 43 .

[0037] The battery monitoring unit 41 detects the voltage of each of the secondary batteries 21. When the detected voltage of at least one of the secondary batteries 21 is lower than a first threshold, the battery monitoring unit 41 outputs a discharge disable signal (for example, an L-level voltage signal) to the discharge control unit 42. When the detected voltage of at least one of the secondary batteries 21 is higher than a second threshold, the battery monitoring unit 41 outputs a charge disable signal (for example, an H-level voltage signal) to the charge control unit 43. When the detected voltage of each of the secondary batteries 21 is equal to or higher than the first threshold and equal to or lower than the second threshold, the battery monitoring unit 41 outputs a discharge permission signal (for example, an H-level voltage signal) and a charge permission signal (for example, an L-level voltage signal). The battery monitoring unit 41 includes an IC (Integrated Circuit) element. The battery monitoring unit 41 operates using the power storage unit 2 as a power source. The battery monitoring unit 41 is mounted on a circuit board. The circuit board is, for example, configured by a printed wiring board.

[0038] The discharge control unit 42 is connected to the battery monitoring unit 41 so as to obtain the discharge permission signal and the discharge disable signal output from the battery monitoring unit 41. The discharge control unit 42 is also connected to a first output terminal 71 among the multiple communication terminals 70. The discharge control unit 42 performs voltage conversion and logical inversion of the signals (discharge permission signal and discharge disable signal) output from and input to the battery monitoring unit 41 and outputs the converted signals. When the discharge disable signal is output from the battery monitoring unit 41, the discharge control unit 42 outputs a first signal (for example, a voltage signal of H level). The discharge control unit 42 includes, for example, a signal conversion circuit. The signal conversion circuit has, for example, an npn-type transistor, a resistor, and a Zener diode. In the signal conversion circuit, the collector of the npn-type transistor is connected to the high-potential side output terminal of the power supply circuit in the battery pack 1 via a resistor, and the emitter of the npn-type transistor is connected to the ground. In the discharge control unit 42, the battery monitoring unit 41 is also connected to the base of the npn-type transistor. An output end (a connection point with the resistor of the transistor) of the discharge control unit 42 is connected to the first output terminal 71. The cathode of the Zener diode is connected to the collector of the npn-type transistor, and the anode of the Zener diode is connected to the emitter of the npn-type transistor. When the power tool 100 receives the first signal output from the first output terminal 71, the power tool 100 determines that the battery pack 1 is undervoltage. When the power tool 100 receives the first signal while discharging the power tool 100 to a load, the power tool 100 stops discharging. The discharge control unit 42 is mounted on the circuit board.

[0039] The charging control unit 43 is connected to the battery monitoring unit 41 so as to obtain the charging permission signal and charging disable signal output from the battery monitoring unit 41. The charging control unit 43 is also connected to one second output terminal 72 of the multiple communication terminals 70. The charging control unit 43 performs voltage conversion and logical inversion of the signals (charging permission signal and charging disable signal) output from and input to the battery monitoring unit 41 and outputs the converted signals. When the charging disable signal is output from the battery monitoring unit 41, the charging control unit 43 outputs a second signal (for example, a voltage signal of L level). The charging control unit 43 includes, for example, a signal conversion circuit. The signal conversion path has an npn-type transistor, a resistor, and a Zener diode. In the signal conversion circuit, the collector of the npn-type transistor is connected to the high-potential side output terminal of the power supply circuit in the battery pack 1 via a resistor, and the emitter of the npn-type transistor is connected to the ground. In the charging control unit 43, the battery monitoring unit 41 is also connected to the base of the npn-type transistor. An output end (a connection point between the transistor and the resistor) of the charging control unit 43 is connected to the second output terminal 72. In addition, the cathode of the Zener diode is connected to the collector of the npn-type transistor, and the anode of the Zener diode is connected to the emitter of the npn-type transistor. When the charger receives the second signal output from the second output terminal 72, it determines that the battery pack 1 is in a fully charged state. When the charger receives the second signal while charging the battery pack 1, it stops charging the battery pack 1. The charging control unit 43 is mounted on the above-mentioned circuit board.

[0040] The information output unit 6 is connected to the communication connector 7. The information output unit 6 outputs battery pack information via the communication connector 7. The information output unit 6 includes a constant voltage output unit 61 and an identification information output unit 62. The information output unit 6 also includes a plurality of switch elements 10 (two in this embodiment).

[0041] The constant voltage output unit 61 outputs a dummy signal including a constant voltage signal that is a constant voltage. The lithium ion battery serving as the secondary battery 21 has a temperature sensor unit and outputs temperature information to the power tool 100 via the temperature detection terminal 75. Here, the temperature detection terminal 75 is a terminal that receives a signal related to the temperature detected by the lithium ion battery from the lithium ion battery.

[0042] The secondary battery 21 may be, for example, a lithium ion battery, a nickel cadmium battery, or an all-solid-state battery 35. In this embodiment, the all-solid-state battery 35 is used as the secondary battery 21. Therefore, it is not necessary to measure the temperature by a temperature sensor and output the temperature to the power tool 100 via the temperature detection terminal 75. However, when comparing the case where the secondary battery 21 is composed of a lithium ion battery with the case where the secondary battery 21 is composed of an all-solid-state battery 35, the battery pack 1 does not operate unless a signal related to the temperature of the lithium ion battery is output to the temperature detection terminal 75. For this reason, even when the all-solid-state battery 35 is used as the secondary battery 21, the power storage unit 2 includes a signal output terminal (third output terminal) 73 that outputs a signal to the temperature detection terminal 75. However, the signal output by the signal output terminal 73 includes a dummy signal corresponding to the temperature detection terminal 75. In this embodiment, the dummy signal includes a constant voltage signal that is a constant voltage output by the constant voltage output unit 61. Since the power tool 100 uses the all-solid-state battery 35 in the power storage unit 2 of the battery pack 1, the signal output terminal 73 outputs a dummy signal.

[0043] When a lithium-ion battery is used, temperature management is important to ensure stable operation of the lithium-ion battery. The electrolyte used in the lithium-ion battery has a heat-sensitive characteristic, and the temperature detection terminal 75 is an essential component of the lithium-ion battery, and the operating temperature range of the lithium-ion battery is determined. When temperature information is transmitted to the main body 50 of the power tool 100 via the temperature detection terminal 75, the main body 50 determines that the operation of the power tool 100 can be continued if the temperature information of the lithium-ion battery is within the operating temperature range. The operating temperature range is, for example, 0 degrees to 35 degrees. On the other hand, when the temperature information transmitted to the main body 50 exceeds the operating temperature range of the lithium-ion battery, the main body 50 determines that the operation of the power tool 100 cannot be continued, and stops the operation of the power tool 100.

[0044] The all-solid-state battery 35 used in this embodiment uses a solid electrolyte, which reduces the possibility of electrolyte leakage, fire, etc., compared to a lithium-ion battery, and is therefore more reliable than a lithium-ion battery. In addition, the all-solid-state battery 35 has a high stability of the solid electrolyte, and can be used in high and low temperature conditions. For this reason, when the all-solid-state battery 35 is used, there is no need to measure the temperature of the all-solid-state battery 35. However, in order to determine the operation of the power tool 100 using the temperature information, the main body 50 requires temperature information even when the power storage unit 2 of the battery pack 1 is composed of the all-solid-state battery 35. For this reason, when the power storage unit 2 is composed of the all-solid-state battery 35, a dummy signal is output to the temperature detection terminal 75, and the main body 50, having received the dummy signal, determines that the all-solid-state battery 35 is at a certain temperature within the usable range, and determines that the operation of the power tool 100 can be continued.

[0045] The identification information output unit 62 outputs rated voltage information of the battery pack 1 (information representing the rated voltage of the power storage unit 2 in this embodiment) as the battery pack information. That is, the information output unit 6 outputs rated voltage information of the battery pack 1 as the battery pack information. If the rated voltage of the battery pack 1 is, for example, 18.0 V, the rated voltage information is, for example, a voltage signal with a voltage level of 2.5 V. The identification information output unit 62 is accommodated in the housing 9. The identification information output unit 62 is connected to one fourth output terminal 74 of the multiple communication terminals 70. The identification information output unit 62 includes an identification resistor. The resistance value of the identification resistor is predetermined to be different from each other for each rated voltage of the power storage unit. Therefore, in the battery pack 1, the output signal of the identification information output unit 62 output from the fourth output terminal 74 is different for each battery pack 1 having a different rated voltage. The identification information output unit 62 is mounted on the above-mentioned circuit board. In the power tool 100 to which the battery pack 1 is attached and in the charger, the rated voltage information of the battery pack 1 can be obtained, for example, by detecting the resistance value of the identification resistor.

[0046] In the power tool 100 to which the battery pack 1 is attached, if the temperature information (voltage level of the voltage signal) is within a first predetermined range and the rated voltage information (voltage level of the voltage signal) is within a second predetermined range, it is possible to discharge the power tool 100 to a load. In addition, in the charger to which the battery pack 1 is attached, if the temperature information (voltage level of the voltage signal) is within a third predetermined range and the rated voltage information (voltage level of the voltage signal) is within a fourth predetermined range, it is possible to charge the battery pack 1.

[0047] Each switch element 10 is, for example, a normally-on type transistor. One switch element 11 of the two switch elements 10 is connected between the third output terminal 73 of the constant voltage output unit 61, and the other switch element 12 is connected between the identification information output unit 62 and the fourth output terminal 74. Each switch element 10 is mounted on the circuit board.

[0048] In the battery pack 1, the discharge control unit 42 and the charge control unit 43 of the processing unit 4 are connected to the determination unit 5.

[0049] In the processing unit 4, the discharge control unit 42 outputs the same signal to the first output terminal 71 and the determination unit 5. Also, in the processing unit 4, the charge control unit 43 outputs the same signal to the second output terminal 72 and the determination unit 5. Therefore, in the battery pack 1, when a discharge disable signal is output from the battery monitoring unit 41, the determination unit 5 acquires the first signal. Also, in the battery pack 1, when a charge disable signal is output from the battery monitoring unit 41, the determination unit 5 acquires the second signal.

[0050] The determination unit 5 determines that the battery pack 1 is in an abnormal state when it receives both the first signal and the second signal from the processing unit 4. The battery pack 1 includes an output terminal 79 for outputting a third signal indicating an abnormality when the determination unit 5 determines that the battery pack 1 is in an abnormal state. In the battery pack 1, the third output terminal 73 and the fourth output terminal 74 of the multiple communication terminals 70 also serve as the output terminal 79. When the determination unit 5 receives both the first signal and the second signal, the determination unit 5 controls each of the multiple switch elements 10 from an on state to an off state, thereby putting the third output terminal 73 and the fourth output terminal 74 in a high impedance state (open), thereby outputting the third signal indicating an abnormality. The third signal output from the third output terminal 73 is a voltage signal having a voltage level that is not included in either the first predetermined range or the third predetermined range. The fourth signal output from the fourth output terminal 74 is a voltage signal having a voltage level that is not included in either the second predetermined range or the fourth predetermined range. The determination unit 5 is configured by an IC, but is not limited thereto, and may be configured by a logic circuit or the like. The determination unit 5 is mounted on the above-mentioned circuit board.

[0051] The notification section 8 in the battery pack 1 notifies the user that the battery pack 1 is in an abnormal state when the determination section 5 determines that the battery pack 1 is in an abnormal state.

[0052] The notification unit 8 includes an LED (Light Emitting Diode) provided in the housing 9. The notification unit 8 is controlled by the determination unit 5. The determination unit 5 operates the notification unit 8 so that the LED of the notification unit 8 flashes or lights up for a predetermined time (e.g., 20 seconds).

[0053] (4) Operation The operation of the battery pack 1 will be described with reference to Fig. 1. The power storage section 2 of the battery pack 1 is composed of an all-solid-state battery 35.

[0054] When the battery pack 1 is attached to the main body 50, the battery pack 1 outputs temperature information (dummy signal) from the information output unit 6 to the main body 50 via the third output terminal 73. In this embodiment, the constant voltage output unit 61 outputs a constant voltage signal, which is a constant voltage, to the main body 50 via the signal output terminal 73. Therefore, the main body 50 determines that the temperature information of the battery pack 1 is a constant temperature and is within the operating temperature range, and continues operation of the power tool 100. In other words, the user can continue using the power tool 100.

[0055] The operation will be described in the case where the power storage unit 2 is composed of a plurality of all-solid-state batteries 35 as the secondary batteries 21. In this case, the processing unit 4 detects the voltage of each of the secondary batteries 21, and when the detected voltage of at least one of the secondary batteries 21 is lower than a first threshold value, outputs a first signal to the main body unit 50 of the electric power tool 100 via a first output terminal 71 of the plurality of communication terminals 70. The processing unit 4 also outputs the first signal to the determination unit 5. The processing unit 4 detects the voltage of each of the secondary batteries 21, and when the detected voltage of at least one of the secondary batteries 21 is higher than a second threshold value that is higher than the first threshold value, outputs a second signal to the main body unit 50 of the electric power tool 100 via a second output terminal 72 of the plurality of communication terminals 70. The processing unit 4 also outputs the second signal to the determination unit 5. When both the first signal and the second signal are transmitted to the main body unit 50 of the electric power tool 100, the determination unit 5 determines that an abnormal state has occurred.

[0056] (5) Advantages The battery pack 1 is used in the power tool 100. The battery pack 1 includes a power storage unit 2, and a positive terminal 31 and a negative terminal 32, which are power supply terminals. The power storage unit 2 includes a secondary battery 21. The battery pack 1 supplies power to a main body 50 of the power tool 100 via the positive terminal 31 and the negative terminal 32, which are power supply terminals. The power storage unit 2 includes, as the secondary battery 21, an all-solid-state battery 35 having a solid electrolyte as a separator that separates the positive electrode and the negative electrode. The power storage unit 2 includes a signal output terminal 73 corresponding to a temperature detection terminal 75 that outputs the temperature of the power storage unit 2.

[0057] This configuration makes it possible to provide a battery pack 1 and a power tool 100 with improved applicability. For example, when the temperature of the environment in which the power tool 100 is used is high, or when the power tool 100 is used continuously and the temperature of the battery pack 1 of the power tool 100 rises, the temperature may exceed the operating temperature range of a lithium-ion battery, and power supply and discharge of the battery pack 1 are prohibited, resulting in poor work efficiency. In contrast, in this embodiment, by using an all-solid-state battery 35 having a wider operating temperature range than a lithium-ion battery, the power tool 100 can be used even when the temperature is high and when the power tool is used continuously, and the applicability of the battery pack 1 is improved.

[0058] Even if the secondary battery 21 is an all-solid-state battery 35, the main body 50 of the power tool 100 can perform a determination process as if a lithium-ion battery with an appropriate operating temperature range is being used.

[0059] The signal output from the signal output terminal 73 includes a dummy signal corresponding to the temperature detection terminal 75, and the dummy signal includes a constant voltage signal that is a constant voltage.

[0060] According to this configuration, even if the secondary battery 21 used by the power storage unit 2 is switched from a lithium ion battery to an all-solid-state battery 35, the dummy signal is output to the temperature detection terminal 75, so that it is possible to use the battery pack 1 including the power storage unit 2 composed of the all-solid-state battery 35.

[0061] The electric power tool 100 further includes a plurality of communication terminals 70, a processing unit 4, and a determination unit 5. The plurality of communication terminals 70 output signals to the electric power tool 100. The processing unit 4 detects the voltage of each of the secondary batteries 21, and outputs a first signal to the electric power tool 100 via a first output terminal 71 of the plurality of communication terminals 70 when the detected voltage of at least one of the secondary batteries 21 is lower than a first threshold value. The processing unit 4 outputs a second signal to the electric power tool 100 via a second output terminal 72 of the plurality of communication terminals 70 when the detected voltage of the secondary batteries 21 other than the at least one secondary battery 21 is higher than a second threshold value that is higher than the first threshold value. The determination unit 5 determines that an abnormal state has occurred when the processing unit 4 transmits both the first signal and the second signal to the electric power tool 100.

[0062] With this configuration, the battery pack 1 is able to detect an abnormal state.

[0063] (6) Variations The above embodiment is merely one of various embodiments of the present invention. The above embodiment can be modified in various ways depending on the design and the like as long as the object of the present invention can be achieved. Modifications are listed below. The modifications described below can be applied in appropriate combination with the above embodiment.

[0064] In the embodiment, the dummy signal includes a constant voltage signal that is a constant voltage, but is not limited to this configuration. The dummy signal may include a constant current signal that is a constant current, as in the battery pack 1A shown in FIG. 4, in which the information output unit 6 includes a constant current output unit 61A that outputs a constant current.

[0065] In the embodiment, the dummy signal includes a constant voltage signal that is a constant voltage, but is not limited to this configuration. The dummy signal may include a ground signal, as in the battery pack 1B shown in FIG. 5, in which the information output unit 6 includes a ground (GND) 61B that outputs a ground level.

[0066] In the embodiment, the number of the secondary batteries 21 is five, but is not limited to this. The number of the secondary batteries 21 in the power storage unit 2 may be one or more, and is not limited to five. The number of the secondary batteries 21 may be, for example, four.

[0067] In the embodiment, the battery monitoring unit 41 is configured with an IC element, but is not limited to this configuration. The battery monitoring unit 41 may include an IC element and other electronic components. The battery monitoring unit 41 may also be configured with a microcontroller. The microcontroller is configured as a one-chip device including a processor that operates according to a program, a memory for storing the program that operates the processor, and a working memory. In this case, the battery monitoring unit 41 can be realized by making the microcontroller execute the program. The battery monitoring unit 41 may also be configured to include multiple discrete electronic components without including an IC element and a microcontroller.

[0068] In the embodiment, the information output unit 6 in the battery pack 1 is configured to include two switch elements 10, but is not limited to this configuration. The number of switch elements 10 is not limited to two, and may be one, or three or more.

[0069] In the embodiment, in the battery pack 1, the information output unit 6 is configured to include two switch elements 10, but is not limited to this configuration. The determination unit 5 may be configured to cause the identification information output unit 62 to output a third signal when the determination unit 5 determines that an abnormal state exists.

[0070] In the embodiment, in the battery pack 1, of the multiple (four) communication terminals 70, all (two) of the communication terminals 70 connected to the information output unit 6 are also used as output terminals 79, but it is sufficient that at least one communication terminal 70 is also used as the output terminal 79.

[0071] In the embodiment, the power storage unit 2 is configured to include the thermistor 22, but is not limited to this configuration. The power storage unit 2 does not necessarily have to include a thermistor.

[0072] In the embodiment, the thermistor 22 is configured to be an NTC thermistor, but is not limited to this configuration. The thermistor 22 may be configured to be a PCT thermistor (Positive Temperature Coefficient Thermistor).

[0073] In the embodiment, the resistance value of the identification resistor is predetermined to be different for each rated voltage of the power storage unit, but is not limited to this configuration. The identification information output unit 62 may have a different identification resistance value for each combination of the rated voltage and the rated capacity.

[0074] In the embodiment, the battery pack 1 is configured to include the information output unit 6, the communication connector 7, and the notification unit 8, but is not limited to this configuration. The information output unit 6, the communication connector 7, and the notification unit 8 are not essential components and can be omitted as appropriate.

[0075] In the embodiment, the notification unit 8 is configured to notify by the light emission color, blinking pattern, etc. of the LED, but is not limited to this configuration. The notification unit 8 may also notify by sound. The notification unit 8 may be configured to notify by, for example, a combination of an audio IC and a speaker, a buzzer, etc.

[0076] The battery pack 1 may further include a protection element between the positive terminal 33 and the positive electrode of the power storage unit 2 for cutting off an electric path between the positive terminal 33 and the power storage unit 2. The protection element includes, for example, a heater resistor and a fuse, and when a current flows through the heater resistor, the fuse melts to cut off the electric path. The protection element may be controlled by, for example, the charge control unit 43.

[0077] In the embodiment, the battery pack information is configured to be temperature information and rated voltage information, but is not limited to this configuration. The battery pack information may include, for example, remaining capacity information, rated capacity information, charge count information, etc. The remaining capacity information is information that indicates the remaining capacity of the battery pack 1. The rated capacity information is information that indicates the rated capacity of the battery pack 1. The charge count information is information that indicates the number of times the battery pack 1 has been charged.

[0078] (summary) As described above, the battery pack (1, 1A, 1B) according to the first embodiment is used in a power tool (100). The battery pack (1) includes a power storage unit (2) and a positive terminal (31) and a negative terminal (32) that are power supply terminals. The power storage unit (2) includes a secondary battery (21). The battery pack (1) supplies power to a main body unit (50) of the power tool (100) via the positive terminal (31) and the negative terminal (32) that are power supply terminals. The power storage unit (2) includes an all-solid-state battery (35) having a solid electrolyte as a separator that separates the positive and negative electrodes as the secondary battery (21). The power storage unit (2) includes a signal output terminal (73) corresponding to a temperature detection terminal (75) that outputs the temperature of the power storage unit (2).

[0079] This configuration makes it possible to provide a battery pack (1) and a power tool (100) with improved applicability.

[0080] In the battery pack (1, 1A, 1B) according to the second embodiment, in the first embodiment, the temperature detection terminal (75) is a terminal that receives a signal related to the temperature detected by the lithium ion battery from the lithium ion battery.

[0081] According to this configuration, the battery pack (1, 1A, 1B) is provided with a temperature detection terminal (75), and thus the battery pack (1) used in the power tool (100) can use a lithium ion battery as the secondary battery (21) of the power storage section (2).

[0082] In the battery pack (1, 1A, 1B) according to the third embodiment, in the first embodiment, the signal output from the signal output terminal (73) includes a dummy signal corresponding to the temperature detection terminal (75).

[0083] According to this configuration, in the battery pack (1, 1A, 1B), the signal output from the signal output terminal (73) is a dummy signal corresponding to the temperature detection terminal (75). Therefore, the battery pack (1) used in the power tool (100) can be used with an all-solid-state battery (35) in addition to a lithium-ion battery.

[0084] In a battery pack (1) according to a fourth aspect, in the third aspect, the dummy signal includes a constant voltage signal that is a constant voltage.

[0085] According to this configuration, the dummy signal can be realized by the output of the constant voltage circuit included in the constant voltage output unit 61 by including a constant voltage signal that is a constant voltage.

[0086] A battery pack (1) according to a fifth aspect, in any one of the first to fourth aspects, further includes a plurality of communication terminals (70), a processing unit (4), and a determination unit (5). The plurality of communication terminals (70) output a signal to the electric power tool (100). The processing unit (4) detects the voltage of each of the secondary batteries (21) and outputs a first signal to the electric power tool (100) via a first output terminal (71) of the plurality of communication terminals (70) when a detected voltage of at least one of the secondary batteries (21) is lower than a first threshold value. The processing unit (4) outputs a second signal to the electric power tool (100) via a second output terminal (72) of the plurality of communication terminals (70) when a detected voltage of the secondary batteries (21) other than the at least one secondary battery (21) is higher than a second threshold value that is higher than the first threshold value. The determination unit (5) determines that an abnormal state has occurred when the processing unit (4) transmits both the first signal and the second signal to the power tool (100).

[0087] According to this configuration, the battery pack (1) can detect an abnormal state.

[0088] In the battery pack (1) of the sixth aspect, in the fifth aspect, when the judgment unit (5) judges that an abnormal state exists, the battery pack (1) further includes an information output unit (6) that outputs a third signal indicating the abnormality to the power tool (100) via a third output terminal (73) different from the first output terminal (71) and the second output terminal (72) among the multiple communication terminals (70).

[0089] According to this configuration, the battery pack (1) used in the power tool (100) can output a third signal indicating an abnormality when an abnormality occurs.

[0090] In the battery pack (1) according to the seventh aspect, in the sixth aspect, the information output section (6) outputs battery pack information indicating the state of the battery pack (1) to the power tool (100) via the third output terminal (73).

[0091] According to this configuration, the information output unit (6) outputs the third signal to the power tool (100) via the third output terminal (73) for outputting the third signal, which has the advantage that it is not necessary to provide an output terminal (79) for outputting the third signal separately from the multiple communication terminals (70).

[0092] In a battery pack (1) according to an eighth aspect, in the seventh aspect, the power storage unit (2) includes a thermistor (22), and the battery pack information includes temperature information based on the thermistor (22).

[0093] According to this configuration, the battery pack (1) is equipped with a thermistor, so that temperature information can be obtained even when the battery pack (1) used in the power tool (100) uses an all-solid-state battery (35).

[0094] In the battery pack (1) according to the ninth aspect, in the seventh or eighth aspect, the battery pack information includes rated voltage information indicating a rated voltage of the power storage unit (2).

[0095] According to this configuration, when the power tool (100) or the charger is attached and attempts to detect rated voltage information of the battery pack, if the determination unit (5) determines that an abnormal state is occurring in the battery pack (1), the battery pack (1) is able to output the third signal from the fourth output terminal (74).

[0096] The battery pack (1) according to a tenth aspect is in any one of the fifth to ninth aspects, further comprising a notification unit (8) that issues a notification when the determination unit (5) determines that an abnormal state has occurred.

[0097] According to this configuration, the battery pack (1) can notify that the battery pack (1) is in an abnormal state.

[0098] The power tool (100) according to an eleventh aspect is any of the first to tenth aspects, and includes a battery pack (1) and a main body (50) to which the battery pack (1) is detachably attached.

[0099] According to this configuration, the power tool (100) can use a battery pack (1) using an all-solid-state battery (35) in addition to a battery pack (1) using a lithium-ion battery. [Explanation of symbols]

[0100] 1 Battery pack 2. Power storage unit 4 Processing section 5 Judgment section 6 Information output section 8. Notification Department 21 Secondary battery 22 Thermistor 31 Positive terminal 32 Negative terminal 35 All-solid-state battery 50 Main body 70 Multiple communication terminals 71 First output terminal 72 Second output terminal 73 Signal output terminal 75 Temperature detection terminal 100 Electric tool

Claims

1. A battery pack for use in a power tool, A power storage unit including a secondary battery; A positive terminal and a negative terminal are power supply terminals for supplying power to a main body of the electric power tool, the power storage unit includes, as the secondary battery, an all-solid-state battery having a solid electrolyte as a separator separating a positive electrode and a negative electrode; the power storage unit includes a signal output terminal corresponding to a temperature detection terminal that outputs a temperature of the power storage unit; the signal output terminal includes a dummy signal corresponding to the temperature detection terminal; Battery pack.

2. The dummy signal includes a constant voltage signal that is a constant voltage. The battery pack according to claim 1 .

3. A plurality of communication terminals for outputting signals to the power tool; a processing unit that detects the voltage of each of the secondary batteries, and outputs a first signal to the power tool via a first output terminal of the plurality of communication terminals when a detected voltage of at least one of the secondary batteries is lower than a first threshold, and outputs a second signal to the power tool via a second output terminal of the plurality of communication terminals when a detected voltage of the secondary batteries other than the at least one secondary battery is higher than a second threshold that is higher than the first threshold; and a determination unit that determines that an abnormal state occurs when the processing unit transmits both the first signal and the second signal to the power tool. The battery pack according to claim 1 or 2.

4. The power tool further includes an information output unit that outputs a third signal indicating an abnormality to the power tool via a third output terminal among the plurality of communication terminals that is different from the first output terminal and the second output terminal when the determination unit determines that an abnormal state exists. The battery pack according to claim 3 .

5. The information output unit outputs battery pack information indicating a state of the battery pack to the power tool via the third output terminal. The battery pack according to claim 4.

6. The power storage unit includes a thermistor, the battery pack information includes temperature information based on the thermistor; The battery pack according to claim 5 .

7. The battery pack information includes rated voltage information indicating a rated voltage of the power storage unit. The battery pack according to claim 5 or 6.

8. Further comprising an alarm unit that notifies when the determination unit determines that an abnormal state exists. The battery pack according to any one of claims 3 to 7.

9. An electric tool comprising a battery pack according to any one of claims 1 to 8 and a main body to which the battery pack is detachably attached.

Images