JP2013180677A - Battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a battery that is hardly deteriorated and can be used for a long time without increasing an economic burden on a user.SOLUTION: A replaceable battery 11 mounted to a small electric vehicle 12 includes: a battery cell 24 having a charged capacity of a predetermined upper limit value; and a memory 33 where information is rewritable on a setting upper limit value of the charged capacity for completing charging which is equal to or lower than the upper limit value of the charged capacity.

Description

  The present invention relates to a battery mounted on a small electric vehicle.

  A battery mounted on a small electric vehicle such as an electric motorcycle, an electric bicycle that supplements the driving force by human power with an electric motor, or an electric wheelchair is smaller than a battery mounted on a large electric four-wheel vehicle. For this reason, the performance of a battery for a small electric vehicle often deteriorates earlier than the end of the useful life of the small electric vehicle. Thus, it is known that a battery mounted on a small electric vehicle can be replaced (see Patent Document 1).

JP 2008-166208 A

  By the way, since a battery is comparatively expensive, the user's economic burden when replacing the battery is large. For this reason, a battery whose performance is hardly deteriorated as much as possible is desired from the market.

  Therefore, an object of the present invention is to provide a battery that does not deteriorate and can be used for a long time without increasing the economic burden on the user.

The battery of the present invention that can solve the above problems is a battery that is mounted on a small electric vehicle in an exchangeable manner,
A battery cell with a predetermined upper limit of charge capacity;
A memory capable of rewriting information on a set upper limit value of the charge capacity at which charging is terminated, which is equal to or lower than the upper limit value of the charge capacity.

  The battery of the present invention may be rechargeable by being removed from the small electric vehicle.

  The battery of the present invention may include a switch for switching a setting upper limit value of the charging capacity.

According to the present invention, a setting upper limit lower than the upper limit value of the charge capacity is provided by providing a memory capable of rewriting the information on the upper limit value of the charge capacity at which charging is terminated, which is equal to or lower than the predetermined upper limit value of the charge capacity. You can finish charging with the value. Thereby, deterioration of the performance of a battery can be suppressed and a battery can be used for a long time.
Further, a memory capable of rewriting the information on the set upper limit value of the charging capacity is provided in the battery. For this reason, when replacing the battery of an existing small electric vehicle, it is possible to provide a battery that can be used for a long time simply by replacing it with such a battery. Therefore, since it is not necessary to modify the vehicle, the economic burden on the user does not increase.

1 is a system configuration diagram of a battery, a small electric vehicle to which a battery is connected, and a charger according to the present embodiment. It is a flowchart explaining the charge operation to a battery.

Hereinafter, an example of an embodiment of a battery according to the present invention will be described with reference to the drawings.
FIG. 1 is a system configuration diagram of a battery, a small electric vehicle to which the battery is connected, and a charger according to the present embodiment.

  As shown in FIG. 1, the battery 11 according to this embodiment is connected to a vehicle 12 as a small electric vehicle and supplies electric power to the vehicle 12. The battery 11 is charged by the charger 13. The battery 11 according to the present embodiment is replaceably mounted on a small electric vehicle such as an electric motorcycle, an electric bicycle that supplements a driving force by human power with an electric motor, or an electric wheelchair.

  The vehicle 12 includes a motor 63 that is driven by electric power from the battery 11, a motor drive circuit 61 that drives the motor 63, and a motor drive command unit 62 that transmits a control command to the motor drive circuit 61. The motor drive command unit 62 transmits a drive command signal to the motor drive circuit 61 in accordance with, for example, the accelerator opening. Thereby, the motor drive circuit 61 outputs the electric power from the battery 11 to the motor 63 based on the drive command signal, and drives the motor 63 to run the vehicle 12.

  The vehicle 12 includes a power supply line Lv and a communication line Lcv connected to the motor drive circuit 61. The power line Lv is connected to the power line Lb of the battery 11. The communication line Lcv is connected to the communication interface 52 of the battery 11. When the power supply line Lb and the power supply line Lv are connected to each other, power can be supplied from the battery 11 to the motor 63. Further, the communication between the battery 11 and the vehicle 12 is enabled by connecting the communication line Lcv and the communication interface 52.

  The charger 13 includes an AC / DC converter 70, a DC / DC converter 71, and a charger controller 72. The AC / DC converter 70 is provided with a plug 74 that can be connected to an external power source (not shown).

  A power line Lc is connected to the AC / DC converter 70 and the DC / DC converter 71. The power supply line Lc is provided with a voltage detector 75 and a current detector 76. The voltage detector 75 and the current detector 76 detect the charging voltage and charging current flowing through the power supply line Lc. The detected charging voltage and charging current are transmitted to the charger controller 72.

  The charger control unit 72 transmits an output control signal to the DC / DC converter 71 to control the DC / DC converter 71. The DC / DC converter 71 supplies power to the power supply line Lc with a predetermined charging voltage or charging current based on the output control signal from the charger control unit 72.

  The charger 13 is provided with a display driver 77, a display unit 78, and a communication interface 79. The display driver 77 and the communication interface 79 are connected to the charger controller 72. The communication interface 79 enables communication with the battery 11 when connected to the battery 11.

  The display unit 78 is connected to the display driver 77. A display signal from the charger control unit 72 is input to the display unit 78 via the display driver 77. The display unit 78 can employ an LED lamp. For example, a charging state such as charging and completion of charging can be displayed by turning on / off the LED lamp.

  When the power supply line Lc of the charger 13 is connected to the power supply line Lb of the battery 11, power can be supplied from the charger 13 to the battery 11. Further, when the communication interface 79 of the charger 13 is connected to the communication interface 53 of the battery 11, communication between the charger 13 and the battery 11 becomes possible.

  The battery 11 according to the present embodiment is mounted on the vehicle 12 in a replaceable manner. The battery 11 includes a plurality of battery cells 24, a cutoff circuit 22, and a battery CPU 23. The battery CPU 23 has a function as a so-called battery management system (BMS).

  For example, a lithium ion cell or a nickel metal hydride cell can be adopted as the battery cell 24 capable of storing electricity. The battery cell 24 has both electrodes connected to the power supply line Lb.

  The cutoff circuit 22 is provided in the power supply line Lb. In the non-charged state, the disconnection circuit 22 disconnects the connection between the battery cell 24 and the charger 13, and the disconnection of the connection is released only during charging.

  A voltage detection unit 25 and a current detection unit 26 are provided on the power supply line Lb of the battery 11. The voltage detector 25 detects the voltage of the battery cell 24. Further, the current detection unit 26 detects a current flowing through the power supply line Lb. The detection signals of these voltage detection unit 25 and current detection unit 26 are transmitted to the battery CPU 23, respectively.

  The battery CPU 23 controls charging / discharging of the battery cell 24. The battery CPU 23 includes an information storage unit 31 and a charge control unit 32. The charge control unit 32 is provided with a rewritable memory 33. The memory 33 is written with the voltage (set upper limit voltage) of the battery cell 24 when the charging of the battery cell 24 is stopped.

  The information storage unit 31 is composed of, for example, a nonvolatile memory (EEPROM). The information storage unit 31 includes an upper limit value storage unit 41 in which the first set upper limit voltage V1 and the second set upper limit voltage V2 are stored, a capacity information storage unit 42, and a history storage unit 43. . The information stored in the upper limit storage unit 41, the capacity information storage unit 42, and the history storage unit 43 can be read out by the charge control unit 32.

  The capacity information storage unit 42 stores a charging voltage when the battery cell 24 is charged to a predetermined upper limit value of the charging capacity. For example, when a lithium ion cell is used as the battery cell 24, the charging voltage when charged to the upper limit value of the predetermined charging capacity is 4.2V. The history storage unit 43 stores a charge / discharge history of the battery cell 24.

  The first set upper limit voltage V1 and the second set upper limit voltage V2 stored in the upper limit storage unit 41 are values equal to or lower than the upper limit when the battery cell 24 is charged to the upper limit of the charge capacity. For example, when a lithium ion cell is employed as the battery cell 24, the first set upper limit voltage V1 can be set to 4.2V, and the second set upper limit voltage V2 can be set to 3.8V.

  The battery CPU 23 stops the charging operation based on the set upper limit voltage written in the memory 33 at the time of charging. Specifically, when the output from the voltage detection unit 25 becomes equal to the set upper limit voltage of the memory 33, a cutoff signal is transmitted to the cutoff circuit 22, and charging of the battery cell 24 is stopped. That is, the battery cell 24 is charged only up to the set upper limit voltage written in the memory 33.

  A changeover switch 45 is connected to the charging control unit 32. With the changeover switch 45, the value input to the memory 33 can be rewritten to one of the first set upper limit voltage V1 and the second set upper limit voltage V2 stored in the upper limit storage unit 41. it can. That is, the changeover switch 45 can select whether the battery cell 24 is charged to the first set upper limit voltage V1 or to the second set upper limit voltage V2.

  The battery 11 is provided with a display device 51 and communication interfaces 52 and 53. These display device 51 and communication interfaces 52 and 53 are connected to the battery CPU 23. A display signal from the battery CPU 23 is transmitted to the display device 51, and the state of charge of the battery cell 24 and the like are displayed. The communication interface 52 enables communication with the vehicle 12 when connected to the vehicle 12. Further, the communication interface 53 enables communication with the charger 13 when connected to the charger 13.

  Next, the charging operation to the battery 11 according to the present embodiment will be described along the flowchart shown in FIG.

  When the charger 13 is connected to the external power source and the battery 11, the battery 11 can be charged. First, the charge control unit 32 of the battery CPU 23 reads a signal from the changeover switch 45 and determines whether the first set upper limit voltage V1 is set as the set upper limit voltage or the second set upper limit voltage V2 is set. Determination is made (step S01).

  Here, when the first set upper limit voltage V1 is selected by the changeover switch 45 (step S01: Yes), the charging control unit 32 sets 4.2 V, for example, as the first set upper limit voltage V1 in the memory 33. Write (step S02). On the other hand, when the second set upper limit voltage V2 is selected by the changeover switch 45 (step S01: No), the charge control unit 32 stores 3.8V as the second set upper limit voltage V2 in the memory 33. Is written (step S03). In this way, the set upper limit voltage, which is the upper limit voltage for stopping charging during charging, is written in the memory 33.

  Next, the battery CPU 23 releases the interruption of the connection between the charger 13 and the battery cell 24 by the interruption circuit 22 and starts charging the battery cell 24. At this time, the battery cell control unit 23 compares the set upper limit voltage stored in the memory 33 with the voltage of the battery cell 24 input from the voltage detection unit 25, and the voltage of the battery cell 24 becomes the set upper limit voltage. Charge until.

  The battery CPU 23 continues charging when the voltage of the battery cell 24 is less than the set upper limit voltage (step S04: No). When the voltage of the battery cell 24 reaches the set upper limit voltage (step S04: Yes), the battery CPU 23 operates the cutoff circuit 22, shuts off the battery cell 24 and the charger 13, and stops charging (step S05). Thus, according to the battery 11 according to the present embodiment, the charging can be terminated at a set upper limit value equal to or less than the upper limit value with respect to the upper limit value of the charge capacity predetermined for the battery cell 24. .

  As described above, the battery 11 according to the present embodiment has the memory 33 that can rewrite the information on the set upper limit value of the charge capacity for ending the charge that is the same as or smaller than the predetermined upper limit value of the charge capacity. Is provided. Thus, by selecting a set upper limit value (second set charge voltage V2) lower than the predetermined upper limit value of the charge capacity as the set upper limit value, the charge capacity lower than the upper limit value of the original charge capacity of the battery cell 24 To finish charging. In general, when a battery cell is charged up to the full upper limit of the original predetermined charging capacity, performance such as battery capacity is likely to deteriorate. On the other hand, the battery 11 according to the present embodiment can be used so that the performance of the battery 11 is not easily deteriorated because it can be selected to end the charging without charging up to the upper limit value.

  In addition, when the battery 11 is normally charged with the second set upper limit voltage V2 of 3.8 V and the performance is not easily deteriorated, on the other hand, particularly when it is assumed that the battery 11 moves for a longer distance than usual. Can be easily used properly, such as charging at 4.2 V which is the first set upper limit voltage V1 and increasing the travelable distance. Therefore, according to the user's request at that time, it is possible to provide a usage that gives priority to prevention of performance degradation or increases convenience by increasing the travel distance.

  In addition, since the battery 11 is provided with a memory 33 that can rewrite information on the set upper limit value of the charging capacity, the battery 11 is replaced when the battery of an existing small electric vehicle or the like is replaced. Only by doing, it can be set as the vehicle 12 provided with the battery 11 which can be used for a long time without adding a hand to a small electric vehicle. Therefore, not only for the user who newly purchases the small electric vehicle, but also the economic burden on the user who owns the existing small electric vehicle can be suppressed.

  Moreover, the existing battery is generally equipped with the battery management system (BMS) which monitors the charging / discharging state of a battery cell. Therefore, the battery 11 according to the present embodiment can provide the battery 11 whose performance is hardly deteriorated by a simple method of adding the memory 33 to the battery CPU 23 having the BMS function. That is, it is possible to provide the battery 11 whose performance is not easily deteriorated at low cost.

  Further, the battery 11 according to the present embodiment is detachably mounted on the vehicle 12. Thereby, even if the battery 11 is removed from the vehicle 12 and the battery 11 is charged only by the battery 11 and the charger 13, the battery 11 can be charged with the set upper limit value in which the performance is unlikely to deteriorate. That is, it is not necessary to give information on the set upper limit value to the vehicle or the charger. The battery 11 may be charged while mounted on the vehicle 12.

  Further, according to the battery 11 according to the present embodiment, since the battery 11 is provided with the charge control unit 32 that controls charging, if the charger 13 and the battery 11 are energized, the vehicle 12 is not energized. Can also be charged. Therefore, it is possible to eliminate a power loss caused by energizing the vehicle 12 during charging.

  Further, since the changeover switch 45 is provided in the battery 11, the set upper limit value of the charge capacity can be switched by the battery 11 alone. Thereby, even if it removes from the vehicle 12 and charges the battery 11 alone, the battery 11 can be charged with the set upper limit value in which the performance hardly deteriorates. That is, the vehicle 12 and the charger 13 do not have to have a function of switching information on the set upper limit value.

  In the above embodiment, the example in which the changeover switch 45 is provided in the battery 11 has been described. However, the changeover switch 45 may be provided in the vehicle 12 or the charger 13. In addition, a control circuit that controls charging and the information storage unit 31 may also be provided in the vehicle 12 or the charger 13.

  Further, the battery 11 according to the present embodiment may be mounted on the vehicle 12 so as to be replaceable, and may be mounted on the vehicle 12 so as to be easily detachable, or may be bolted to the vehicle 12.

  In the above embodiment, the case where the charging voltage is used as the set upper limit value for terminating the charging has been described, but the present invention is not limited to this example. For example, the amount of electricity [Ah] stored in the battery cell 24 can be used as the set upper limit value.

  In this case, the upper limit value (for example, 10 Ah) of the charge capacity set in advance in the battery cell 24 that is recorded in the capacity information storage unit 42 of the battery 11, and the upper limit value of the charge capacity that terminates charging ( For example, 10 Ah or 8 Ah) can be written into the memory 33.

  As a result, when 8 Ah is selected as the set upper limit value, the charge control unit 32 charges the battery cell 24 while comparing the charged amount in the history storage unit 43 with the set upper limit value (8 Ah) in the memory 33. Charging is terminated when the amount of stored electricity reaches the set upper limit value of the memory 33. This also makes it possible to selectively perform charging with a set upper limit value that is smaller than the upper limit value of the charge capacity, and to provide the battery 11 whose performance is unlikely to deteriorate.

  Moreover, although the example mentioned above gave and demonstrated the example which memorize | stored specific numerical values, such as 4.2V, 3.8V, 10Ah, and 8Ah, in the memory 33, this invention is not limited to this example. For example, information regarding the set upper limit value may be stored in the rewritable memory 33 so that the case where the performance is not deteriorated and the case where the travelable distance is increased are encoded with 0, 1 and this code is stored. good.

  The numerical values such as 4.2V, 3.8V, 10Ah, and 8Ah described above are merely examples, and the present invention is not limited to these numerical values.

  In the above-described embodiment, an example in which one of the first setting upper limit value and the second setting upper limit value is written in the memory 33 as the setting upper limit value has been described. However, the present invention is not limited to this example. As the set upper limit value, any one of two or more set upper limit values below the predetermined upper limit value of the charging capacity may be written in the memory 33 as the set upper limit value.

  In the above-described embodiment, the example of charging with the set upper limit value selected at the start of charging has been described. However, the present invention is not limited to this example. For example, the setting upper limit value may be changed by operating the changeover switch 45 during charging, and charging may be terminated at this setting upper limit value. Thereby, even during the charging of the battery 11, a set upper limit value lower than the upper limit value of the original charge capacity of the battery cell 24 can be selected, and the battery 11 can be charged so that the performance is not easily deteriorated.

  In addition, various design changes can be made within the scope of matters described in the claims.

11: Battery, 12: Small electric vehicle, 13: Charger, 24: Battery cell, 33: Memory

Claims (3)

A battery that is replaceably mounted on a small electric vehicle,
A battery cell with a predetermined upper limit of charge capacity;
A battery comprising: a memory capable of rewriting information on a set upper limit value of a charge capacity for ending charging, which is equal to or lower than the upper limit value of the charge capacity.   The battery according to claim 1, wherein the battery is removable from a small electric vehicle and can be charged. The said battery is a battery of Claim 1 or 2 provided with the switch which switches the setting upper limit of charge capacity.

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