POWER STORAGE PACK AND ELECTRIC MOVING BODY

In a power storage pack, a power storage unit feeds electric power to an electric moving body. A controller superimposes a current pattern representing identification information of the power storage pack on electric power to be supplied to electric moving body. The controller generates a current pattern with current values of a plurality of levels other than zero level. The controller may superimpose a current pattern on electric power supplied to an electric moving body through a precharge circuit.

TECHNICAL FIELD

The present disclosure relates to a power storage pack detachable to an electric moving body, and an electric moving body.

BACKGROUND ART

Recently, electrically assisted bicycles have become popular. Electrically assisted bicycles use a detachable and portable battery pack. In order to eliminate terminals for communication lines from a connector of a battery pack, a system has been developed in which a wireless communication function is installed on the battery pack and an electrically assisted bicycle to transmit control signals wirelessly.

When a plurality of electrically assisted bicycles is present within a range capable of being wirelessly communicated with a battery pack, there is a risk that the mounted battery pack may be incorrectly controlled by another vehicle adjacent to the own vehicle, so that safety and security of the entire system cannot be ensured. In particular, in rental services and sharing services, a plurality of electrically assisted bicycles may often be parked in one bicycle-parking space. For operating the entire system safely and securely, individual electrically assisted bicycles need to correctly identify the mounted battery pack.

PTL 1 discloses a technique of checking connection between a vehicle and a power feeding device using wireless communication when a vehicle in which the power storage device is installed is connected to a power feeding device disposed outside with a charging cable. The connection of the power feeding device with the vehicle is recognized based on patterns of supply and cutoff of electric power from the power feeding device and pattern information transmitted wirelessly.

CITATION LIST

Patent Literature

SUMMARY OF THE INVENTION

In general, simple vehicles like electrically assisted bicycles do not incorporate a dedicated battery to operate a control circuit, and are supplied with a control power source from a mounted power battery pack. In this case, even if identification information of the battery pack is notified from the battery pack to a vehicle in a pattern of power supply and cutoff using a power line, it is difficult to detect the identification information at the vehicle.

The present disclosure has been made in view of the above-mentioned circumstances. An object of the present disclosure is to provide a technology of notifying identification information easily detected at an electric moving body from a power storage pack to an electric moving body using a power line.

In order to solve the above-mentioned problem, a power storage pack of one aspect of the present disclosure includes a power storage unit for feeding electric power to an electric moving body, and a controller superimposing a current pattern representing identification information of the power storage pack on the electric power supplied to the electric moving body. The controller generates the current pattern with current values of a plurality of levels other than zero level.

According to the present disclosure, identification information easily detected at an electric moving body can be notified from a power storage pack to an electric moving body using a power line.

DESCRIPTION OF EMBODIMENT

FIG.1is a view showing an overall configuration of a management service of a battery pack in accordance with an exemplary embodiment. Battery pack10is a detachable and portable/replaceable battery pack10and can be mounted on a mounting slot of vehicle20or a charger (not shown). Hereinafter, in the exemplary embodiment, an electrically assisted bicycle is assumed as vehicle20.

Since replaceable battery pack10frequently undergoes attachment and detachment with respect to the mounting slot of vehicle20or a charger, a connector part of battery pack10is easily deteriorated. Thus, in this exemplary embodiment, a wireless communication function is installed in battery pack10to transmit control signals by wireless communication. This can eliminate a terminal for a communication line from the connector of battery pack10, and can only use a terminal for a power line.

For wireless communication between vehicle20and battery pack10, near-field wireless communication is used. Examples of the near-field wireless communication include Bluetooth (registered trademark), Wi-Fi (registered trademark), infrared communication, and the like. Hereinafter, in this exemplary embodiment, use of BLE (Bluetooth Low Energy) is assumed as the near-field wireless communication.

The BLE is one of the extended standards of Bluetooth and a low power consumption and near-field wireless communication standard using the 2.4 GHz band. The BLE is suitable for battery drive because the BLE consumes electric power that is low enough to allow several years of driving with a single button battery, thus minimizing the impact on the remaining capacity of battery pack10. Many modules for BLE communications have been shipped to the market, and therefore are available at low cost.

Furthermore, the BLE is highly compatible with smartphones and can provide a variety of services linked with smartphones. In this exemplary embodiment, battery pack10and portable terminal device30possessed by a user are connected by near-field wireless communication. Examples of portable terminal device30include a smartphone, a smart watch, a tablet, a small laptop computer, a portable game instrument, and the like. Hereinafter, in this exemplary embodiment, a smartphone is assumed as portable terminal device30. It is assumed that battery pack10and a smartphone are connected by BLE.

Battery pack management system3is a system that collectively manages states of a plurality of battery packs10. Battery pack management system3is constructed on, for example, the battery manufacturer's own server placed in its own facility or a data center, or on a cloud server used based on a cloud service agreement. Note here that battery pack management systems3may be constructed not by battery manufacturers but by operating entities providing rental service and a sharing service of electrically assisted bicycles.

Battery pack management system3and portable terminal device30are connected to network2. Network2is a generic term for communication paths such as the Internet, leased lines, and virtual private networks (VPNs), regardless of a communication medium or a protocol. Examples of the communication medium include a mobile phone network (cellular network), a wireless local area network (LAN), a wired LAN, an optical fiber network, an Asymmetric Digital Subscriber Loop (ADSL) network, a community antenna television (CATV) network, and the like. Examples of the communication protocol include TCP (Transmission Control Protocol)/IP (Internet Protocol), UDP (User Datagram Protocol)/IP, Ethernet (registered trademark), and the like.

In this exemplary embodiment, portable terminal device30is connected to network2via a base station or a Wi-Fi access point of the 4G/5G cellular network. Battery pack management system3is connected to network2through a router. Battery pack10is connected to portable terminal device30by near-field wireless communication, and thereby can be indirectly connected to devices on the Internet.

Battery pack management system3manages basic information including identification information (pack ID), date of manufacture, owner information (name, address, phone number, e-mail address, etc.), and warranty contents, of each battery pack10. In the case of battery pack10used for rental and sharing services of electrically assisted bicycles, an owner and a manager may be different from each other. In that case, battery pack management system3also manages information of the manager. In addition, battery pack management system3can also manage user information of users who currently rent and use electrically assisted bicycles.

Battery pack management system3can obtain status information indicating the present state of each battery pack10paired with each mobile terminal device30through mobile terminal device30of each user. For example, the SOH (State of Health) of battery pack10can be obtained. When the SOH of battery pack10falls below a predetermined value, battery pack management system3can notify by email an owner or a manager of a state that battery pack10should be replaced.

Furthermore, battery pack management system3can also obtain present location information of battery pack10via portable terminal device30. As the present location information of battery pack10, GPS (Global Positioning System) information of the paired mobile terminal device30can be used. In the case of rental and sharing services, battery pack management system3can notify portable terminal device30of a user who is currently using the electrically assisted bicycle of a return location of the electrically assisted bicycle. A radio wave coverage of the BLE is about 10 meters when a typical Class2device is used. Therefore, a state in which a plurality of vehicles20a,20band a plurality of battery packs10a,10bare present in one communication range of BLE may occur. In such a case, radio wave interference may occur between vehicle systems, resulting in an unstable operation. Furthermore, vehicle20may be misconnected to battery pack10other than battery pack10mounted in the vehicle. In such a case, battery pack10that is not mounted may be controlled incorrectly.

Thus, a mechanism is required to ensure that battery pack10mounted on vehicle20and battery pack10of a communication partner of vehicle20are identical. In this exemplary embodiment, identification information (ID) is used to check that battery pack10physically connected to vehicle20by wire and the battery pack10connected by wireless communication are identical to each other. The identification information (ID) may be identification information unique to each battery pack10or may be temporal identification information. As unique identification information, for example, a Bluetooth Device (BD) address or Medium Access Control (MAC) address may be used.

FIG.2is a diagram to illustrate an outline of authentication processing of battery pack10to be mounted on vehicle20. When the connector of battery pack10is connected to a connector of the mounting slot of vehicle20, battery pack10transmits ID1through wire. At the same time, battery pack10sends an advertisement packet (beacon packet) including ID1via near-field wireless communication. The advertisement packet is a signal used for announcing one's presence to the surroundings via near-field wireless communication.

Vehicle20receives an advertisement packet, and then collates the ID1included in the advertisement packet and the ID1received through wire. When both match, vehicle20authenticates that mounted battery pack10is identical to the communication partner of the near-field wireless communication. When both do not match, vehicle20determines that mounted battery pack10is not identical to the communication partner of the near-field wireless communication and does not authenticate battery pack10of the communication partner. For example, when an advertisement packet including ID2is received, since the ID2does not match the ID1received through wire, vehicle20does not authenticate battery pack10to which the advertisement packet including ID2is transmitted.

FIG.3is a diagram showing a configuration example of vehicle20of battery pack10in accordance with the exemplary embodiment. An example shown inFIG.3presumes a state in which battery pack10is mounted on vehicle20.

Battery pack10includes storage battery11, main relay12, first power source circuit14, first controller15, first wireless communication unit16, first antenna17, precharge circuit18, and power feeding terminal T1. Vehicle20includes motor21, inverter22, capacitor23, second power source circuit24, second controller25, second wireless communication unit26, second antenna27, current sensor28, and power receiving terminal T2. In a state in which battery pack10is mounted on vehicle20, power feeding terminal T1and power receiving terminal T2are brought into physical contact with each other, and the power line Lp1in battery pack10and power line Lp2in vehicle20are electrically conducted.

Storage battery11includes a plurality of cells connected in series or series-parallel. Examples of the cells that can be used include a lithium-ion battery cell, a nickel-metal hydride battery cell, a lead battery cell, and the like. Hereafter, in the specification, using a lithium-ion battery cell (nominal voltage: 3.6 V to 3.7 V) is assumed as an example. The number of cells connected in series is determined according to a driving voltage of motor21of vehicle20.

Main relay12is inserted into power line Lp1that connects between storage battery11and power feeding terminal T1. Instead of a relay, other types of switches such as a semiconductor switch may be used. Precharge circuit18is connected in parallel with main relay12. A specific circuit configuration example of precharge circuit18is described later.

First power source circuit14is a DC/DC converter that reduces a voltage of storage battery11to generate a power source voltage (for example, about 3.3 V to 5 V) of first controller15. First power source circuit14may include a switching regulator or a linear regulator.

First controller15is a microcontroller that controls entire battery pack10. First controller15monitors a state of storage battery11(specifically, a voltage, a current, and a temperature of each cell included in storage battery11). Based on these monitored data, first controller15estimates the SOC (State of Charge), FCC (Full Charge Capacity), and SOH of each cell included in storage battery11. Furthermore, when an overvoltage, an undervoltage, an overcurrent, an abnormal high temperature or an abnormal low temperature occurs in a cell included in storage battery11, first controller15turns off main relay12to protect the cell.

First wireless communication unit16executes near-field wireless communication processing. In this exemplary embodiment, first wireless communication unit16includes a BLE module. First antenna17includes a chip antenna or a pattern antenna incorporated in the BLE module. First wireless communication unit16outputs data received by near-field wireless communication to first controller15and transmits data input from first controller15by near-field wireless communication.

In this exemplary embodiment, vehicle20includes a three-phase AC motor as motor21for driving. Inverter22converts DC power supplied from battery pack10into AC power and supplies it to motor21during power running. During regeneration, AC power supplied from motor21is converted into DC power and supplied it to battery pack10. Motor21rotates according to the AC power supplied from inverter22during power running. During regeneration, rotational energy by deceleration is converted into AC power and supplied to inverter22.

Capacitor23is connected in parallel to power line Lp2that connects between power receiving terminal T2and inverter22. More specifically, capacitor23is connected between the positive wiring of power line Lp2and the negative wiring (or ground potential). For capacitor23, for example, a large-capacity film capacitor is used. Capacitor23is used to stabilize the operation of inverter22by absorbing the voltage fluctuation of the power line Lp2and the spike noise generated by the switching operation of inverter22, or to protect it from failure. When power source is turned on, since a large inrush current flows from battery pack10to charge capacitor23, a precharge process is performed to charge capacitor23to a predetermined voltage while limiting the supply current to the power line Lp2when power source is turned on.

Second power source circuit24is a DC/DC converter that reduces a voltage supplied from storage battery11in battery pack10mounted on vehicle20and generates the power source voltage (for example, about 3.3 V to 5 V) of second controller25. Second power source circuit24may include a switching regulator or a linear regulator. In this exemplary embodiment, in vehicle20, own battery (for example, a lead battery) for generating a control power source is not installed. Therefore, it is necessary to generate the control power source from the power source supplied from storage battery11in the mounted battery pack10.

Current sensor28detects a current flowing through power line Lp2in vehicle20, and outputs the detected current to second controller25. Current sensor28includes a combination of, for example, a CT sensor and a current detection circuit. The current detection circuit outputs a current flowing through a coil wound around a magnetic core of the CT sensor and a current detection value as a voltage value taken out by the shunt resistor to second controller25. Instead of the CT system, a Hall element system, a Rogowski coil system, or the like, may be used.

Second controller25is a microcontroller that controls entire vehicle20. Second wireless communication unit26performs near-field wireless communication processing. In this exemplary embodiment, second wireless communication unit26includes a BLE module, second antenna27can be formed of a chip antenna or a pattern antenna incorporated in the BLE module. Second wireless communication unit26outputs data received by near-field wireless communication to second controller25, and transmits data input from second controller25by near-field wireless communication.

FIG.4is a view showing a circuit configuration example of precharge circuit18ofFIG.3. Precharge circuit18shown inFIG.4includes a constant current circuit capable of outputting current values of a plurality of levels. Precharge circuit18includes an operational amplifier OP1, a Zener diode ZD1, a voltage dividing resistor R1, a resistor R2, a variable resistor part Rv and a P-channel MOSFET (Metal Oxide Semiconductor Field Effect Transistor) (M1).

A variable resistor part Rv and a P-channel MOSFET (M1) are connected in series between an input node N1and an output node N2of precharge circuit18. The source terminal of the P-channel MOSFET (M1) is connected to the variable resistor part Rv, and the drain terminal of the P-channel MOSFET (M1) is connected to the output node N2. A voltage Vb of storage battery11(a voltage of input node N1) is applied to the gate terminal of the P-channel MOSFET (M1) via resistor R2. Note here that instead of the P-channel MOSFET (M1), a bipolar transistor may be used.

The voltage Vb of storage battery11is divided by a Zener diode ZD1and a voltage dividing resistor R1to generate a reference voltage V′, and the reference voltage V′ is input into a non-inverting input terminal of the operational amplifier OP1. The inverted input terminal of the operational amplifier OP1is connected to a node between the variable resistor part Rv and the FET (M1). The output terminal of the operational amplifier OP1is connected to the gate terminal of the P-channel MOSFET (M1).

The current Iout output from precharge circuit18to output node N2is defined by the following mathematical formula (Math. 1) where Rs is a resistance value of a variable resistor part Rv:

In Example shown inFIG.4, the variable resistor part Rv includes a first limiting resistor Rs1, a second limiting resistor Rs2, a first switch SW1, and a second switch SW2. First switch SW1and first limiting resistor Rs1are connected in series, second switch SW2and second limiting resistor Rs2are connected in series, and two series circuits are connected in parallel. For example, MOSFETs can be used for the first switch SW1and the second switch SW2.

First controller15can make the resistance value Rs of the variable resistor part Rv variable by controlling on/off of the first switch SW1and on/off of the second switch SW2. Hereafter, the resistance value of the first limiting resistor Rs1is lower than the resistance value of the second limiting resistor Rs2.

First controller15can set the resistance value Rs of the variable resistor part Rv to the resistance value of the first limiting resistor Rs1by controlling the first switch SW1on and the second switch SW2off. At this time, first current value I1is output from precharge circuit18(seeFIG.5described later). First controller15causes first switch SW1to be turned on, and second switch SW2to be turned off, thereby, the resistance value Rs of variable resistor part Rv can be set to the resistance value of second limiting resistor Rs2. At this time, second current value12is output from precharge circuit18(seeFIG.5described later).

First controller15causes first switch SW1and second switch SW2to be turned on, and thereby, the resistance value Rs of variable resistor part Rv can be set to a synthesis resistance value of first limiting resistor Rs1and second limiting resistor Rs2. First controller15can cause precharge circuit18to be turned off by causing first switch SW1and second switch SW2to be turned off.

In this way, in precharge circuit18shown inFIG.4, since resistance value Rs of variable resistor part Rv can be switched among three types, precharge circuit18can output three levels of current values. Note here that by further increasing the number of limiting resistors connected in parallel, four levels or more of current values can be output.

In the example shown inFIG.4, the limiting resistor between the input node N1and the output node N2is made variable, but the limiting resistor may be made to be fixed and the voltage dividing resistor R1may be made variable. In this case, precharge circuit18can output current values of a plurality of levels by making the reference voltage V+variable.

FIG.5is a waveform diagram showing an example of an operation from battery pack10to vehicle20when the power source is turned on. When battery pack10is mounted on vehicle20, and an operation of turning on the power source of vehicle20is carried out, first controller15of battery pack10firstly turns on precharge circuit18without turning on main relay12. In the example shown inFIG.5, first controller15turns on the first switch SW1in precharge circuit18to allow a current to flow from storage battery11to vehicle20side through first limiting resistor Rs1.

The current supplied from storage battery11to vehicle20side charges capacitor23in vehicle20, and voltage Vc of capacitor23is increased. When voltage Vc of capacitor23rises to a voltage at which second power source circuit24is operable, the power source voltage starts to be supplied from second power source circuit24to second controller25, and second controller25is activated.

When a predetermined time has passed after precharge circuit18is turned on, first controller15superimposes a current pattern representing ID of battery pack10(hereinafter, referred to as “pack ID”) on the electric power supplied from storage battery11to vehicle20through precharge circuit18. The predetermined time is set to a time period longer than time necessary for activating second controller25after start of supplying vehicle20with electric power. That is, when power supply to vehicle20is started, first controller15generates a current pattern through precharge circuit18after a predetermined time longer than elapsed time until reaching an operable voltage of second power source circuit24that generates the power source voltage of vehicle20from electric power fed from storage battery11.

As described above, first controller15controls variable resistor part Rv inside precharge circuit18, thus enabling first current value I1and second current value12to be output from precharge circuit18. In the example shown inFIG.5, first current value I1is assigned to the high level of the pack ID specified in binary number, and the second current value12is assigned to the low level of the pack ID specified in binary number. First controller15switches between first current value I1and second current value12depending on the level of each bit of pack ID. First current value I1and second current value12are set to values other than zero.

Current sensor28in vehicle20detects a current Io flowing in power line Lp2in vehicle20and outputs the detected current Io to second controller25. Second controller25detects a current pattern superimposed on electric power supplied from battery pack10based on the current Io detected by current sensor28, and reads the pack ID.

First controller15of battery pack10allows first wireless communication unit16to transmit an advertisement packet including pack ID identical to the pack ID superimposed on the electric power supplied to vehicle20. Second wireless communication unit26of vehicle20receives the advertisement packet, and then outputs the received advertisement packet to second controller25. Second controller25collates the pack ID included in the advertisement packet with the pack ID read from the current pattern superimposed on the power supplied from battery pack10. When both match, second controller25authenticates that mounted battery pack10is identical to the communication partner of near-field wireless communication.

When the precharge period ends, first controller15turns off precharge circuit18and turns on main relay12. The timing at which the precharge period ends is set at the time when a predetermined period has passed from the end of the ID notification by the current pattern.

FIG.6is a waveform diagram showing another operation example when power source is turned on from battery pack10to vehicle20.FIG.6shows an example in which precharge circuit18can output four levels of current values11,12,13, and14. All of the four levels of current values11,12,13, and14are set to values other than zero.

First controller15converts the pack ID in quinary number, generates a current pattern representing the pack ID specified in quinary number with four levels of current values11,12,13, and14, and superimposes the current pattern on the power supplied to vehicle20. WhenFIG.5andFIG.6are compared with each other, the pack ID notification period is shortened inFIG.6in which a current is multivalued. When the current is further multivalued, the pack ID notification period is further reduced.

As described above, according to this exemplary embodiment, when the pack ID is notified from the battery pack to vehicle20in a precharge current pattern, pack ID that can be easily detected at a vehicle20can be notified using a power line from battery pack10to vehicle20. The precharge current charges capacitor23of vehicle20without being cut off. During the time, by changing the current level of the precharge current, the pack ID is notified from battery pack10to vehicle20.

That is to say, first controller15of battery pack10notifies the pack ID using precharge circuit18at the same time of precharging. Second controller25of vehicle20detects the pack ID using current sensor28. At the time, since the electric power from battery pack10to vehicle20is not cut off, the power source of second controller25is not interrupted even if its own battery is not installed in vehicle20. Therefore, during notification period of the pack ID, second controller25operates normally and can detect the pack ID normally.

In this respect, when the pack ID is notified in the pattern of supply/cutoff of electric power of the power line, in vehicle20in which its own battery is not installed, the power source of second controller25is interrupted at the timing of cutoff of electric power, and the pack ID cannot be detected normally. In this way, in vehicle20such as an electrically assisted bicycle in which its own battery is not installed, the supply of control power source from battery pack10to second controller25need to be maintained at all times, and the voltage or current cannot be temporarily cut off to notify the pack ID. In this respect, in this embodiment, no cutoff of voltage or current occurs during the notification period of the pack ID.

As change of hardware in battery pack10, since precharge circuit18is only configured to be variable, a special circuit for notification and detection of a pack ID is not required to be significantly added. Therefore, the increase in cost and mounting area due to the increase in the number of circuit components can be suppressed.

Furthermore, since notification and detection of the pack ID and the start-up of a power system of vehicle20are performed simultaneously, the time between the start of communication and the start of running can be shortened. As the precharge current is more multivalued, the time required for the notification and detection of the pack ID can be shortened.

In this exemplary embodiment, vehicle20collates the pack ID read out from the precharge current with the pack ID received wirelessly to verify the mounted battery pack10. This prevents accidental misconnection with another battery pack that is present in the surrounding area, ensuring the safety and security of the entire system.

Furthermore, as shown inFIG.4, by configuring precharge circuit18to be a variable constant current source, current values of a plurality of levels can be generated with high accuracy. It is also possible to configure precharge circuit18only with the variable resistor part Rv without using the constant-current source configuration. In this case, costs can be eliminated.

In the above, the present disclosure is described based on the exemplary embodiments. The exemplary embodiments are examples, and a person skilled in the art would easily understand that various modified examples combining the component elements or treatment processing of the exemplary embodiments can be made and that such modified examples are also in the scope of the present disclosure.

In the above exemplary embodiment, an example of battery pack10incorporating storage battery11is described. In this respect, a capacitor pack incorporating a capacitor, including an electric double-layer capacitor cell, a lithium-ion capacitor cell, and the like, may be used. In this specification, a battery pack and a capacitor pack are collectively referred to as a power storage pack.

The disclosure is suitable for application to vehicle20in which its own power source is not installed, but the disclosure does not exclude application to vehicle20in which its own power source is installed. Therefore, vehicle20is not limited to an electrically assisted bicycle, and includes electric bikes (electric scooters), electric kick scooters, electric vehicles (including low-speed electric vehicles such as golf carts and land cars), railway vehicles, and the like. In addition, the objects to which the power storage pack is mounted are not limited to vehicle20, but include, for example, electric moving bodies such as electric vessels and multicopters (drones).

Note here that the exemplary embodiments may be specified by the following items.

[Item 1] A power storage pack (10) including:a power storage unit (11) for feeding electric power to an electric moving body (20); anda controller (15) superimposing a current pattern representing identification information of the power storage pack (10) on electric power to be supplied to the electric moving body (20),wherein the controller (15) generates the current pattern with current values of a plurality of levels other than zero level.

According to this, identification information of the power storage pack (10) easily detected at an electric moving body (20) side can be notified.

[Item 2] The power storage pack (10) described in the item 1, further including:a power line (Lp1), inside the pack, connecting between the power storage unit (11) and a power feeding terminal (T1);a main switch (12) inserted into the power line (Lp1); anda precharge circuit (18) connected in parallel with the main switch (12),wherein the controller (15) superimposes the current pattern on the electric power to be supplied to the electric moving body (20) through the precharge circuit (18).

According to this, since the identification information of the power storage pack (10) is notified using a precharge current supplied when the electric moving body (20) is turned on, time from the start of running to the start of communication can be shortened.

[Item 3] The power storage pack (10) described in the item 2, wherein the precharge circuit (18) includes a variable constant current circuit (18) capable of outputting current values of a plurality of levels.

According to this, current values of a plurality of levels can be output.

[Item 4] The power storage pack (10) described in any one of the items 1 to 3, further including a wireless communication unit (16) transmitting a signal including identification information identical to the identification information superimposed on the electric power to be supplied to the electric moving body (20) via near-field wireless communication.

This can verify that the mounted power storage pack (10) and the power storage pack (10) of a communication partner are identical to each other.

[Item 5] The power storage pack (10) described in any one of the items 1 to 4, wherein when supplying of electric power from the power storage unit (11) to the electric moving body (20) is started, the controller (15) generates the current pattern, after a predetermined time longer than elapsed time until reaching an operable voltage of a power source circuit (24) that generates a power source voltage of the electric moving body (20) from electric power supplied from the power storage unit (11).

According to this, identification information of the power storage pack (10) can be normally conveyed from the power storage pack (10) to the electric moving body (20) in which its own battery is not installed.

[Item 6] A power storage pack (10) including:a power storage unit (11) for feeding electric power to an electric moving body (20); anda controller (15) for superimposing a current pattern representing identification information of the power storage pack (10) on the electric power supplied to the electric moving body (20),wherein when supplying of electric power from the power storage unit (11) to the electric moving body (20) is started, the controller (15) generates the current pattern, after a predetermined time longer than elapsed time until reaching an operable voltage of a power source circuit (24) that generates a power source voltage of the electric moving body (20) from electric power supplied from the power storage unit (11).

The electric moving body (20) may not include a power source in a state in which the power storage pack (10) is not mounted.

The controller (15) may start supplying of electric power to the electric moving body (20) when controller (15) detects that the power storage pack (10) is mounted on the electric moving body (20).

According to this, identification information of the power storage pack (10) can be normally conveyed from the power storage pack (10) to the electric moving body (20) in which its own battery is not installed.

[Item 7] An electric moving body (20) in which the power storage pack (10) described in any one of the items 1 to 6 is mounted, the electric moving body (20) including:a motor (21);a drive circuit (22) driving the motor (21);a power line (Lp2), inside the electric moving body (20), connecting between the drive circuit and a power receiving terminal (T2); anda controller (25) detecting the current pattern superimposed on electric power supplied to the power line (Lp2) and reading out the identification information.

According to this, even if its own battery is not installed in the electric moving body (20), identification information of the power storage pack (10) can be accurately read out.

[Item 8] The electric moving body (20) described in the item 7, further including a capacitor (23) for precharging, in a front stage of the drive circuit (22).

This can reduce an inrush current at the time of start-up.

[Item 9] The electric moving body (20) described in the item 7 or 8, wherein a power source of the controller (25) of the electric moving body (20) is supplied from the power storage pack (10) through the power line (Lp2).

According to this, even if the electric moving body (20) does not include its own battery, the electric moving body (20) can normally operate.

[Item 10] The electric moving body (20) described in any one of the items 7 to 9, further including a wireless communication unit (26) executing near-field wireless communication,wherein the controller (25) of the electric moving body (20) authenticates that the power storage pack (10) mounted on the electric moving body (20) is identical to a communication partner of the near-field wireless communication, when the identification information included in a signal received by the wireless communication unit (26) matches the identification information read out from the current pattern superimposed on electric power supplied to the power line (Lp2).

This can verify that the mounted power storage pack (10) and power storage pack (10) of the communication partner are identical to each other.

REFERENCE SIGNS LIST