Method for charging vehicle

Abstract

To improve convenience to a user in charging a vehicle.SOLUTION: A vehicle 1 is so constituted that a temperature of a battery is adjustable by using power of the battery. A method for charging the vehicle 1 includes steps of: estimating, with respect to each of a plurality of chargers 2, a temperature of the battery when the vehicle arrives at the charger, based on electric energy usable for temperature adjustment of the battery until the vehicle 1 arrives at the charger; estimating at least one of a charge time of the battery by the charger and a charge power quantity, based on the estimated temperature and charge performance of the charger; and suggesting to the user of the vehicle 1, as the charger for charging the battery, at least one of the charger with the shortest estimated charge time and the charger with the maximum estimated charge power quantity among the plurality of chargers 2.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a method for charging a vehicle. [Background technology]

[0002] JP 2020-39226 A (Patent Document 1) discloses a battery cooling control system that enables efficient and effective cooling control of a battery. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-39226 A Summary of the Invention [Problem to be solved by the invention]

[0004] There is a constant demand for improved convenience for users in charging vehicles. The present disclosure has been made to solve the above problems, and one of the objects of the present disclosure is to improve convenience for users in charging their vehicles. [Means for solving the problem]

[0005] A vehicle charging method according to an aspect of the present disclosure is a method for charging a vehicle equipped with a battery. The vehicle is configured to be able to adjust the temperature of the battery using the power of the battery. The charging method includes the steps of: estimating, for each of a plurality of chargers, a temperature of the battery when the vehicle arrives at the charger based on an amount of power available for adjusting the temperature of the battery until the vehicle arrives at the charger; and estimating at least one of a charging time and a charging power amount of the battery by the charger based on the estimated temperature and a charging performance of the charger. The charging method further includes the step of suggesting, to a user of the vehicle, at least one of a charger with the shortest estimated charging time and a charger with the largest estimated charging power amount among the plurality of chargers as a charger for charging the battery.

[0006] In the above method, the temperature of the battery when the vehicle arrives at the charger is estimated based on the amount of power available for adjusting the temperature of the battery until the vehicle arrives at the charger. This temperature estimation may be achieved by machine learning. Then, at least one of the charging time and the amount of charging power is estimated based on the estimated temperature of the battery. By taking the temperature of the battery into consideration, the charging time or the amount of charging power can be estimated with high accuracy, and the user can receive a recommendation of a charger based on the highly accurate estimation result. Therefore, according to the above method, it is possible to shorten the charging time or increase the amount of charging power, thereby improving convenience for the user. Effect of the Invention

[0007] According to the present disclosure, it is possible to improve convenience for users in charging a vehicle. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a diagram for explaining an example of a charging status of a vehicle according to an embodiment of the present disclosure. [Diagram 2] 10 is a flowchart showing an example of a processing procedure of a charger suggestion process according to the present embodiment. [Diagram 3] FIG. 4 is a conceptual diagram showing an example of a map for estimating an adjustment temperature. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference characters, and the description thereof will not be repeated.

[0010] [Embodiment Mode] <External charging status> 1 is a diagram for explaining an example of a charging state of a vehicle in an embodiment of the present disclosure. Vehicle 1 is an electric vehicle equipped with a battery (not shown) for driving. Vehicle 1 is typically a BEV (Battery Electric Vehicle), but may be a PHEV (Plug-in Hybrid Electric Vehicle) or the like. The battery installed in vehicle 1 is externally charged (plug-in charging, contactless charging, etc.) by power supplied from outside the vehicle.

[0011] In addition, the vehicle 1 is configured to be able to adjust the temperature of the battery using the power of the battery. More specifically, although not shown, the vehicle 1 may include an electric heater for heating the battery, a cooling fan for cooling the battery, or a thermal management system (for example, a refrigeration cycle using a heat medium) capable of both heating and cooling the battery.

[0012] A number of chargers are installed along the planned travel route of vehicle 1 or in the vicinity of the planned travel route. When the user wishes to charge vehicle 1 externally, a "charger suggestion process" is executed to suggest a charger to be used for charging the battery from among the multiple chargers. In this example, three chargers 2A to 2C are extracted as candidates. In the following, when there is no need to distinguish between the chargers, they will be referred to as "charger 2."

[0013] The vehicle 1 is configured to be capable of two-way communication with the server 3. The server 3 may be a server managed by the manufacturer of the vehicle 1, or may be a server managed by an administrator of the charger 2 (such as a charging service provider). The server 3 is capable of providing the vehicle 1 with location information of the charger 2, and is also capable of providing the vehicle 1 with information regarding the charging performance of the charger 2 (such as maximum supply power and maximum supply current).

[0014] Generally, there is a constant demand for improved convenience for users in external charging of a vehicle. For example, by shortening the charging time, the user's waiting time for external charging can be shortened. Also, by increasing the amount of charging energy, the interval until the next external charging can be lengthened, thereby reducing the number of times external charging is performed.

[0015] The input characteristics of the battery (such as maximum chargeable power) determined from the viewpoint of protecting the battery (such as suppressing deterioration and extending the lifespan) vary depending on the battery temperature, and as described above, the vehicle 1 is configured to be able to adjust the battery temperature using the battery's power. In this embodiment, therefore, the charging time and amount of charging power for each charger 2 are calculated taking into account the battery temperature adjustment function. More specifically, the ECU (Electronic Control Unit) of the vehicle 1 estimates the battery temperature when the vehicle 1 arrives at each charger 2, and calculates the charging time and amount of charging power based on the temperature. The ECU then suggests to the user of the vehicle 1 that external charging be performed using a charger with a short charging time and / or a charger with a large amount of charging power. This charger suggestion process will be described in detail below.

[0016] <Processing flow> 2 is a flowchart showing an example of a processing procedure for the charger suggestion process in this embodiment. The process shown in this flowchart is executed when a predetermined condition is met (when the user of vehicle 1 requests external charging of vehicle 1, when the remaining capacity of the battery falls below a reference amount, etc.). Each step is realized by software processing by the ECU of vehicle 1, but may also be realized by hardware (electrical circuitry) arranged in the ECU. Hereinafter, steps are abbreviated as S.

[0017] In S1, the ECU extracts chargers that the vehicle 1 can reach from among the multiple chargers 2. For example, the ECU extracts two or more chargers that are installed on (or near) the planned driving route of the vehicle 1 from among the multiple chargers 2. Then, taking into consideration the remaining capacity of the battery, the ECU extracts two or more chargers that are located within a range from the current location of the vehicle 1 that is shorter than the driving distance (cruising distance) of the vehicle 1. In the example of FIG. 1, three chargers 2A to 2C are extracted.

[0018] The following processes in S2 to S7 are executed for each of the two or more chargers extracted in S1, that is, in the example of Fig. 1, the processes are executed separately for the chargers 2A, 2B, and 2C.

[0019] In S2, the ECU estimates the remaining capacity (remaining energy) P of the battery upon arrival at the charger 2. As one specific example, the ECU calculates the amount of power consumed by the vehicle 1 while traveling from the current location of the vehicle 1 to the charger 2, based on the traveling history of the vehicle 1 and / or other vehicles (e.g., vehicles of the same model). The ECU then estimates the remaining capacity P by subtracting the amount of power consumed from the remaining capacity at the current location.

[0020] In S3, the ECU acquires from a car navigation system (not shown) a required time Δt for the vehicle 1 to arrive at the charger 2 from the current location of the vehicle 1. The required time Δt can be calculated using a known route search technique implemented in the car navigation system.

[0021] In S4, the ECU calculates the available capacity of the battery. The available capacity is calculated by subtracting the remaining capacity P calculated in S2 from the lower limit value P LL Difference from (PP LL ) The lower limit of the remaining capacity P LL is a known value that is set in advance for the purpose of protecting the battery from deterioration (such as over-discharging) and / or for the purpose of maintaining a certain degree of driving range.

[0022] Furthermore, the ECU calculates the amount of power that can be adjusted to the temperature of the battery. The amount of power that can be adjusted to the temperature is the product (Wmax x Δt) of the maximum power Wmax that can be adjusted to the temperature and the required time Δt calculated in S3 (in other words, the time integral of the power). The maximum power Wmax is a known value that is determined according to the power consumption specifications (especially the maximum power) of devices used to adjust the battery temperature, such as electric heaters, cooling fans, and thermal management systems.

[0023] Then, the ECU calculates the difference (PP LL ) or the time integral (Wmax×Δt), whichever is smaller, is calculated as the amount of power Pava that the vehicle 1 can use to adjust the temperature of the battery.

[0024] Pava = min(PP LL , Wmax × Δt) (1) In S5, the ECU estimates the temperature after temperature adjustment (the battery temperature heated / cooled during driving) when the vehicle 1 arrives at the charger 2 based on the amount of power Pava calculated in S4. Hereinafter, this temperature is referred to as "adjusted temperature Tadj." For example, a map such as the one shown below is used for this estimation.

[0025] 3 is a conceptual diagram showing an example of a map for estimating the adjustment temperature Tadj. The map is, for example, a three-dimensional map including the battery temperature (current temperature) Tpre at the current location of the vehicle 1, the amount of power Pava, and the adjustment temperature Tadj. The map is prepared based on a previous measurement result and stored in the memory of the ECU. The current temperature Tpre is the current value of the temperature detected by a battery temperature sensor (not shown). By referring to such a map, it is possible to estimate the adjustment temperature Tadj from the current temperature Tpre and the amount of power Pava.

[0026] A map for when the battery is heating up is shown in Fig. 3. A similar map can be prepared for when the battery is cooling down.

[0027] 2 again, in S6, the ECU estimates the charging time of the battery by the charger 2 based on the adjustment temperature Tadj estimated in S5 and the charging performance (output characteristics) of the charger 2. In general, when the battery is at an extremely low or high temperature, the maximum acceptable power of the battery is low, whereas in the temperature range between these temperatures, the maximum acceptable power of the battery is relatively high. The ECU can estimate the charging time of the battery by the charger 2, for example, based on the remaining capacity P of the battery upon arrival at the charger 2 (estimated value in S2), the maximum acceptable power of the battery according to the adjustment temperature Tadj (known value), and the maximum supply power of the charger 2 (value acquired from the server 3).

[0028] In S7, the ECU estimates the amount of power to be charged to the battery by the charger 2 based on the adjustment temperature Tadj estimated in S5 and the charging performance of the charger 2. For example, the ECU estimates the time that can be spent on external charging by the charger 2 on the condition that the vehicle 1 arrives at the destination by a desired target time. The ECU calculates the amount of power that can be charged by the charger 2 within the above-mentioned time based on the maximum receiving power of the battery according to the adjustment temperature Tadj and the maximum supply power of the charger 2. Alternatively, the ECU acquires the specified charging time per charge of the charger 2, and calculates the amount of power that can be charged by the charger 2 within the above-mentioned time based on the maximum receiving power of the battery according to the adjustment temperature Tadj and the maximum supply power of the charger 2.

[0029] In S8, the ECU proposes to the user (for example, displays on an HMI (Human Machine Interface)) the charger with the shortest charging time estimated in S6 or the charger with the largest amount of charging power estimated in S7 from among the two or more chargers extracted in S1 as a candidate charger suitable for charging the battery. The ECU may propose only one of the two chargers or may propose both. This allows the user to select the charger with the shortest charging time or the charger with the largest amount of charging power.

[0030] As described above, in this embodiment, the amount of power (W max × Δt), the battery temperature when the vehicle 1 arrives at the charger 2 is estimated. Then, the charging time and the amount of charging energy are estimated based on the estimated battery temperature. By taking the battery temperature into consideration, the charging time and the amount of charging energy can be estimated with high accuracy, and the user can receive a proposal of a charger 2 based on the highly accurate estimation result. Therefore, according to this embodiment, it is possible to shorten the charging time and increase the amount of charging energy, thereby improving convenience for the user.

[0031] In the present embodiment, the charger suggestion process has been described as being executed by the vehicle 1. However, the charger suggestion process may be executed by an external device of the vehicle 1 (for example, the server 3 in FIG. 1).

[0032] The charger recommendation process may be combined with a charging reservation system. The charging reservation system may cooperate with the vehicle 1 (or the server 3) that performs the charger recommendation process to reserve a charger selected by the user from among the charger with the shortest charging time and the charger with the largest amount of charging power.

[0033] In addition, by taking into account the reservation status of chargers by other vehicles, the ECU can more appropriately extract chargers to be recommended to the user. For example, the ECU can exclude chargers that are already in use or have already been reserved for charging from the suggestions.

[0034] In addition, according to the present embodiment, since the charging time and / or the amount of charging energy of the battery is estimated with high accuracy, it is possible to accurately determine the time period during which the charger 2 must be secured for external charging of the vehicle 1. Therefore, it is possible to suggest to the user a charger that is installed at an appropriate position along the planned driving route of the vehicle 1 and that can be reserved at an appropriate time period. By reserving such a charger 2, it is possible to shorten the arrival time of the vehicle 1 to the destination. Furthermore, since it is possible to prevent the reservation time for the vehicle 1 from being set excessively long, it is possible for other vehicles to quickly use the charger 2 after external charging of the vehicle 1 is completed. In other words, it is possible to shorten the available time of the charger 2 and improve the usage rate of the charger 2.

[0035] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present disclosure is defined by the claims, not by the description of the embodiments described above, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0036] 1 vehicle, 2(2A~2C) chargers, 3 servers.

Claims

[Claim 1] A method for charging a vehicle equipped with a battery, comprising the steps of: the vehicle is configured to be able to adjust a temperature of the battery by using power of the battery; The charging method includes: For each of the plurality of chargers, estimating a temperature of the battery when the vehicle arrives at the charger based on an amount of power that can be used for adjusting the temperature of the battery until the vehicle arrives at the charger; and estimating at least one of a charging time and a charging energy amount of the battery by the charger based on the estimated temperature and a charging performance of the charger, and further comprising: A vehicle charging method comprising a step of suggesting to a user of the vehicle at least one of the charger having the shortest estimated charging time and the charger having the largest estimated amount of charging power among the plurality of chargers as a charger for charging the battery.

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