Battery temperature estimation method and system

Abstract

The present invention provides a battery temperature estimation method and system for improving charging efficiency by managing the temperature of a high-voltage battery provided in an electric vehicle during charging of the high-voltage battery. This is achieved by sharing a cooling liquid managed by a battery charging device for thermal management of the high-voltage battery outside the vehicle with a cooling liquid of the high-voltage battery so as to supply cooled or heated cooling liquid to the high-voltage battery. Further, the battery temperature estimation method and system estimate a current battery temperature and a future battery temperature based on the battery charging device information and the vehicle information to optimize a coolant temperature during charging of the vehicle battery using the battery charging device. Thus, charging efficiency and energy efficiency are improved.

Description

Technical Field

[0001] The present invention relates to a battery temperature estimation method and system for optimizing the battery temperature when charging a vehicle battery using a battery charging device. Background Art

[0002] In view of the continuous progress in electric vehicle technology, people are paying more and more attention to the technology related to the thermal management of high-voltage batteries in electric vehicles. The high-voltage battery, which plays the same role as the engine in a conventional internal combustion engine vehicle, is even more sensitive to temperature than the engine. If the high-voltage battery overheats, damage due to degradation is likely to occur and its power efficiency is also significantly reduced. Therefore, in order to ensure efficient thermal management of the high-voltage battery, electric vehicles are equipped with cooling lines for the high-voltage battery.

[0003] Heat is generated not only when the vehicle is driven using the high-voltage battery, but also when the high-voltage battery is charged. In particular, more heat is generated during high-speed charging of the high-voltage battery, which may cause degradation of the high-voltage battery or reduced charging efficiency. In addition, when the external temperature is very low, the charging efficiency may also be reduced during charging of the high-voltage battery.

[0004] The contents described above as background art are provided only to enhance the understanding of the background of the invention and should not be regarded as an admission that they correspond to the prior art already known to those of ordinary skill in the art. Summary of the invention

[0005] The present invention aims to solve the above problems. In particular, in order to manage the thermal conditions of the high-voltage battery in an electric vehicle, the cooling fluid circulating in the high-voltage battery is shared with an external battery charging device located outside the electric vehicle. This enables the supply of cooled or heated cooling fluid to the high-voltage battery during charging, thereby improving the charging efficiency by temperature management of the high-voltage battery during charging.

[0006] Another object of the present invention is to improve charging efficiency by managing the temperature of a high-voltage battery when charging the high-voltage battery provided in an electric vehicle. This is achieved by sharing the heated or cooled coolant with the coolant managed by a battery charging device outside the electric vehicle and supplying the coolant to the high-voltage battery of the electric vehicle.

[0007] Another object of the present invention is to provide a battery temperature estimation method and system for estimating current and future battery temperatures based on information about a battery charging device and vehicle information to optimize the temperature of a coolant when charging a vehicle battery using a battery charging device, thereby improving charging efficiency and energy efficiency.

[0008] In one aspect of the present invention, a battery temperature estimation method estimates the battery temperature based on a coolant shared between a vehicle and a battery charging device outside the vehicle during battery charging. The method includes: collecting vehicle information (e.g., electric vehicle information), the vehicle information including a voltage, a state of charge (SoC), and a target charging current of a vehicle battery. The method includes: collecting charging device information, the charging device information including a coolant temperature and a charging current in a battery charging device. In addition, the method includes: estimating the battery temperature of the vehicle through machine learning based on the vehicle information and the charging device information.

[0009] Estimating the battery temperature may include: collecting information about the vehicle and the battery charging device by communicating with a server (e.g., a processor, a controller, etc.). Estimating the battery temperature may include: when the battery temperature of the vehicle is estimated by the server, the server sends a command signal to control the coolant temperature of the battery charging device.

[0010] Collecting the vehicle information or collecting the charging device information may include further collecting information about the external temperature.

[0011] Collecting the charging device information may include collecting a flow rate, an inlet-side coolant temperature, and an outlet-side coolant temperature of a coolant provided to the vehicle during battery charging.

[0012] Estimating the battery temperature may further include estimating a minimum temperature and a maximum temperature of the battery based on the vehicle information and the charging device information.

[0013] The method may further include determining a coolant temperature, in which determining the coolant temperature determines whether to heat or cool the coolant in the battery charging device based on data about the minimum and maximum temperatures of the battery and the SoC derived in estimating the battery temperature.

[0014] Determining the coolant temperature may further include pre-storing a set flow rate and a set temperature, the set flow rate and the set temperature depending on a result of determining whether to heat or cool the coolant.

[0015] Determining the coolant temperature may further include determining whether to heat or cool the coolant by comparing the maximum temperature of the battery with a preset safety temperature when the heating condition is determined according to the minimum temperature of the battery and the cooling condition is determined according to the maximum temperature of the battery.

[0016] Determining the coolant temperature may further include: when the maximum temperature of the battery is lower than a preset safety temperature, determining to heat the coolant.

[0017] Determining the coolant temperature may further include: when the maximum temperature of the battery is higher than a preset safety temperature, determining to cool the coolant.

[0018] Estimating the battery temperature may further include: estimating a predicted temperature based on the vehicle information and the charging device information, the predicted temperature corresponding to the battery temperature when the SoC is the set SoC. In addition, determining the coolant temperature may further include: determining whether the battery is overcooled or overheated by comparing a pre-derived optimal set temperature when the SoC is the set SoC with the predicted temperature.

[0019] Determining the coolant temperature may further include: when the predicted temperature is lower than the optimal set temperature, determining that the battery is overcooled; and in the case where it is determined that the battery is overcooled, determining to heat the coolant.

[0020] Determining the coolant temperature may further include: when it is determined that the battery is overcooled and a heating condition is confirmed based on a current minimum battery temperature, determining to heat the coolant.

[0021] Determining the coolant temperature may further include: in the event that the battery is determined to be overcooled, when the current maximum battery temperature is determined to correspond to the cooling condition, comparing the maximum temperature of the battery with a preset safety temperature; when the maximum temperature of the battery is lower than the preset safety temperature, heating the coolant; when the maximum temperature of the battery is higher than the preset safety temperature, cooling the coolant.

[0022] Determining the coolant temperature may further include: determining that the battery is overheated when the predicted temperature is higher than the optimal set temperature; and cooling the coolant in the case where it is determined that the battery is overheated.

[0023] Determining the coolant temperature may further include: when it is determined that the battery is overheated and a heating condition is confirmed based on a current minimum battery temperature, determining to heat the coolant.

[0024] Determining the coolant temperature may further include: in the case where it is determined that the battery is overheated, checking whether a heat pump or heating is used; when operating the heat pump or performing heating, comparing the predicted temperature with a pre-set safety temperature; when the predicted temperature is lower than the safety temperature, determining that the coolant is heated.

[0025] Determining the coolant temperature may further include: when the SoC is less than a set SoC and when the current battery temperature is higher than a preset safety temperature, determining to cool the coolant.

[0026] Determining the coolant temperature may further include releasing the coolant temperature control when the SoC is greater than or equal to the set SoC, when the current battery temperature is higher than a preset safety temperature, or when the current battery temperature is close to a preset optimal set temperature.

[0027] According to another embodiment of the present invention, a method for estimating battery temperature is provided, the method being based on sharing coolant between a vehicle and a battery charging device during battery charging. The method comprises: collecting vehicle information, the vehicle information comprising a voltage, a state of charge (SoC), and a target charging current of a vehicle battery; collecting charging device information, the charging device information comprising a coolant temperature and a charging current in a battery charging device. The method further comprises: estimating a minimum temperature and a maximum temperature of a battery by machine learning based on the vehicle information and the charging device information; determining whether to heat or cool the coolant in the battery charging device based on data on the minimum temperature and the maximum temperature of the battery and the SoC.

[0028] According to a further aspect of the present invention, a system for estimating battery temperature is provided. The system includes a vehicle controller, which is disposed in the vehicle and configured to collect vehicle information, wherein the vehicle information includes the voltage, SoC, and target charging current of the battery. The system also includes a charging device controller, which is disposed in the battery charging device and configured to: collect charging device information, wherein the charging device information includes the coolant temperature and charging current in the battery charging device; estimate the minimum temperature and maximum temperature of the battery through machine learning based on the vehicle information and the charging device information; and determine whether to heat or cool the coolant based on the data on the minimum temperature and maximum temperature of the battery and the SoC. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The above and other objects, features and other advantages of the present invention will be more clearly understood through the following detailed description presented in conjunction with the accompanying drawings, in which:

[0030] Figure 1 is a flow chart of a battery temperature estimation method according to the present invention;

[0031] Figure 2 is a configuration diagram of a battery temperature estimation system according to an embodiment of the present invention;

[0032] Figure 3 is a circuit diagram of a battery charging device according to an embodiment of the present invention;

[0033] Figure 4 is a curve diagram describing the relationship between the current state of charge of the battery and the temperature of the battery according to the battery temperature estimation method of the present invention;

[0034] Figure 5 is a schematic diagram describing the minimum temperature and maximum temperature of a battery and the state of charge of the battery according to the battery temperature estimation method of the present invention;

[0035] Figure 6 is a graph describing the minimum and maximum temperatures of the battery and the state of charge of the battery according to the battery temperature estimation method of the present invention;

[0036] Figure 7 is a curve diagram describing the relationship between the current state of charge of the battery and the temperature of the battery according to the battery temperature estimation method of the present invention;

[0037] Figure 8 is a graph comparing the predicted temperature of the battery and the optimal set temperature according to the battery temperature estimation method of the present invention;

[0038] Fig. 9 is a circuit diagram describing control during battery overcooling in a battery temperature estimation system according to an embodiment of the present invention; and

[0039] Fig.10 is a circuit diagram describing control during battery overcooling in a battery temperature estimation system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0040] Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numerals will be used throughout the drawings to refer to the same or like parts.

[0041] The suffixes “module” and “unit” of the elements are used herein for convenience of description and thus may be used interchangeably without having any distinguishable meanings or functions.

[0042] In the following description of the embodiments disclosed in this specification, when it is determined that the detailed description of the known functions and configurations incorporated herein may obscure the subject matter of the present invention, the detailed description of the known functions and configurations incorporated herein will be omitted. In addition, the accompanying drawings are provided only to facilitate the understanding of the embodiments disclosed in this specification, and do not limit the technical spirit disclosed herein, and include all changes, equivalents, and alternatives included in the spirit and scope of the present invention.

[0043] The terms "first" and / or "second" are used to describe various components, but these components are not limited by these terms. These terms are used to distinguish one component from another component.

[0044] When a component is "joined" or "connected" to another component, it should be understood that, although the component may be directly joined or connected to another component, a third component may also exist between the two components. When a component is "directly joined" or "directly connected" to another component, it should be understood that there is no element between the two components.

[0045] Unless the context clearly indicates otherwise, elements described in the singular are intended to include plural elements.

[0046] In this specification, the terms “comprise” or “include” should be further understood to specify the existence of stated features, figures, steps, operations, components, parts or a combination thereof, but do not exclude the existence or addition of one or more other features, figures, steps, operations, components or a combination thereof.

[0047] The controller may include a communication device, a memory, and one or more processors, wherein the communication device communicates with other controllers or sensors to control their functions, the memory stores an operating system, logic instructions, input / output information, etc., and the one or more processors perform determinations, calculations, and decisions required for the control functions.

[0048] When the controller, component, device, element, part, unit, module, etc. of the present invention is described as having a purpose or performing an operation, function, etc., the controller, component, device, element, part, unit or module should be considered as "configured to" meet the purpose or perform the operation or function. Each controller, component, device, element, part, unit, module, etc. can be implemented separately or include a processor and memory as part of the device, such as a non-transitory computer-readable medium.

[0049] It should be understood that the term "vehicle" or other similar terms used herein generally include motor vehicles. Such motor vehicles may include sports utility vehicles (SUVs), buses, trucks, various commercial vehicles, etc. Such motor vehicles may also include ships with various boats and ships, aircraft, etc. Such motor vehicles may also include hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles and other alternative fuel vehicles (e.g., fuels derived from non-petroleum energy sources). As described herein, a hybrid vehicle is a vehicle having two or more power sources, for example, a vehicle that is both electric and gasoline-powered.

[0050] Hereinafter, a battery temperature estimation method and system according to an embodiment of the present invention will be described with reference to the accompanying drawings.

[0051] The present invention is a battery temperature estimation method based on sharing coolant between a vehicle 100 and a battery charging device 200 during battery charging.

[0052] In the case of an electric vehicle, a high-voltage battery (hereinafter referred to as a battery) provided in the vehicle is charged using a charger provided outside the vehicle. Reducing the charging time of an electric vehicle is a very important commercial property.

[0053] However, when charging the battery, the battery temperature may reach a certain temperature to increase the charging current. When the battery reaches a certain temperature or higher, the temperature rises due to self-heating, so the battery may need to be cooled.

[0054] In this way, the temperature of the battery needs to be constantly managed during battery charging, and a large-capacity heater and compressor are required to heat or cool the battery in the vehicle. However, considering capacity limitations and cost savings, it is not desirable to provide a heater and a compressor in the vehicle. In addition, when the battery is not charged, the heater and the compressor installed in the vehicle act as a heavy load, adversely affecting fuel efficiency.

[0055] Accordingly, when charging the battery of the vehicle 100, the battery charging device 200 supplies the vehicle with cooled or heated coolant according to the environment inside and outside the vehicle to improve the charging efficiency by raising the temperature of the battery in cold conditions. After the temperature is sufficiently raised, the battery is cooled to prevent the battery temperature from further rising. Alternatively, in extremely high temperature conditions, the battery is cooled to prevent the battery from overheating. Thus, the charging efficiency can be improved and the battery can be prevented from overheating.

[0056] The present invention collects information about a mobile body (eg, a vehicle) and information about a battery charging device when charging a battery to predict current and future battery temperatures, thereby optimizing the battery temperature by temperature management of a coolant supplied to the battery.

[0057] For this reason, Figure 1 and Figure 2 As shown, the battery temperature estimation method according to the present invention includes step S10, i.e., collecting mobile body (e.g., vehicle) information (e.g., battery voltage, state of charge (SoC) and target charging current of the vehicle battery). The method further includes: collecting charging device information at step S20, wherein the charging device information includes the coolant temperature and charging current in the battery charging device; and estimating the battery temperature of the vehicle based on the vehicle information and the charging device information by machine learning at step S30.

[0058] In the step S10 of collecting vehicle information, vehicle information identified in the vehicle is collected, the vehicle information including battery voltage, SoC and target charging current. The vehicle information may be collected from a battery power management module, and the SoC of the battery may be determined using a charging circuit, a voltage regulator, etc.

[0059] In step S20 of collecting charging device information, the charging device information identified in the battery charging device is collected. The charging device information includes the coolant temperature and the charging current in the battery charging device. The battery charging device may be an external thermal management station configured to supply battery power and coolant.

[0060] refer to Figure 3 , the battery charging device 200 includes a first liquid storage tank 210 and a second liquid storage tank 220 that manage coolants of different temperatures.

[0061] In addition, the battery charging device 200 is configured as a thermal management loop to control the temperature of the refrigerant, the thermal management loop including a thermal management compressor 230 , a thermal management condenser 240 , a thermal management expansion device 250 , and a thermal management evaporator 260 .

[0062] The thermal management condenser 240 is disposed in the first tank 210, so that when the thermal management condenser 240 generates heat, the coolant in the first tank 210 can be heated. The thermal management evaporator 260 is disposed in the second tank 220, so that when the thermal management evaporator 260 absorbs heat, the coolant in the second tank 220 can be cooled.

[0063] Additionally, the first liquid storage tank 210 may be further equipped with a thermal management heater 270 to provide additional heat when the heating of the thermal management condenser 240 is insufficient.

[0064] In addition, in the thermal management circuit of the battery charging device 200 , a valve 280 is applied to a pipeline connected to the vehicle so that the distribution of the coolant can be selectively controlled.

[0065] In this way, the battery charging device 200 is equipped with a coolant supply system for managing the temperature of the coolant and selectively supplying the coolant. Thus, the temperature of the coolant managed by the coolant supply system can be checked.

[0066] In addition, the battery charging device 200 may be equipped with a charging system for power management, and the amount of current supplied to the vehicle (which is electrically connected to the charging system) may be determined by the charging system.

[0067] In particular, the present invention estimates the battery temperature of the vehicle through machine learning based on vehicle information and charging device information.

[0068] As a machine learning technique, deep learning using a highly complex neural network structure (eg, artificial neural network) may be used.

[0069] For this machine learning, random forests, deep neural networks (DNNs), and long short-term memories (LSTMs) can be used, and various deep learning algorithms such as convolutional deep neural networks (CNNs) and recursive Boltzmann machines (RBNs) can be utilized.

[0070] As an example of the above-mentioned machine learning, random forest is a method of separating input features into decision trees when features are input and making predictions by averaging the values ​​of different decision trees.

[0071] Deep neural network learning is a method of repeatedly inputting training data into a neural network and calculating the error between the output of the neural network and the target of the training data. The method also includes backpropagating the error of the neural network from the output layer of the neural network to the input layer, thereby reducing the error to update the weight of each node in the neural network.

[0072] LSTM is a method of erasing unnecessary memory by adding an input gate, a forget gate, and an output gate to a memory cell of a hidden layer. The method also includes determining what needs to be stored and deriving the data value of a function that passes through each gate using a delete gate, an input gate, and an output gate to obtain the value of a hidden state and a cell state. This is used when analyzing values ​​that change over time and is suitable for systems that predict that the history of changes in previous values ​​affects future values.

[0073] As described above, in addition to the above-mentioned deep learning, the present invention can also utilize various machine learning methods. The present invention can also improve the accuracy of battery temperature estimation by collecting multiple machine learning methods or setting the priority of each machine learning method.

[0074] In other words, the present invention derives the battery temperature by applying vehicle information (such as battery voltage, SoC, and target charging current) and charging device information (such as coolant temperature and charging current) to each machine learning technique.

[0075] The vehicle information or the charging device information may further include the vehicle outside temperature. The vehicle outside temperature may be confirmed by an vehicle outside temperature sensor provided in the vehicle or the battery charging device.

[0076] In addition, the charging device information may further include a flow rate of coolant supplied to the vehicle during battery charging, an inlet-side coolant temperature, and an outlet-side coolant temperature.

[0077] When collecting vehicle information and charging device information as described above, the server (e.g., processor, controller, etc.) communicates with the vehicle and the battery charging device to collect information of the vehicle and the battery charging device. In step S30, after the server estimates the battery temperature of the vehicle, the server sends a command signal via communication to control the coolant temperature of the battery charging device.

[0078] In the present invention, information of the vehicle and the battery charging device is collected through direct communication between the vehicle and the battery charging device, and accordingly, the battery temperature can be estimated.

[0079] When each information of the vehicle and the battery charging device is collected and stored in the server, the information is continuously accumulated. In addition, when the battery temperature is estimated by machine learning, the accuracy of the battery temperature estimation can be improved based on the fully obtained data.

[0080] In addition, when machine learning is used in the server to estimate the battery temperature by collecting vehicle information and battery charger information, the battery temperature is quickly derived according to a complex algorithm. As a result, the coolant temperature of the battery charger can be quickly adjusted to the optimal temperature when charging the battery.

[0081] Accordingly, in the step S30 of estimating the battery temperature, the minimum temperature and the maximum temperature of the battery may be estimated based on the vehicle information and the charging device information.

[0082] In other words, since there is a limit in deriving an accurate battery temperature even when the battery temperature is estimated using information through machine learning, the lowest temperature in the battery temperature range derived through machine learning is set as the minimum battery temperature, and the highest temperature is set as the maximum battery temperature. In particular, in the case of the outside temperature, the absolute value is more important than the distribution of the temperature value. Thus, the battery temperature is normalized to the minimum value and the maximum value.

[0083] The battery temperature estimating method may further include a coolant temperature determining step S40 of determining whether to heat or cool the coolant in the battery charging device based on data on the minimum and maximum temperatures of the battery and the SoC derived in the step S30 of estimating the battery temperature.

[0084] In the step S30 of estimating the battery temperature, the current battery temperature and the future battery temperature according to the change in SoC caused by the progress of charging are predicted.

[0085] In other words, if we can Figure 4 As determined in the example, when the current SoC and battery temperature are predicted to be “A”, the SoC and battery temperature are brought to the target point “B” by charging the battery at the optimized battery temperature.

[0086] Accordingly, data on the minimum and maximum temperatures of the battery and the SoC are stored in advance through experiments. As an example, this can be expressed in Figure 5 The schematic diagram and Figure 6 shown in the chart.

[0087] like Figure 5 As shown, it can be determined whether to heat or cool the coolant according to the temperature and SoC of the battery. This can be data predetermined by experiments based on the specifications and charging specifications of the battery.

[0088] Based on this, Figure 6 As shown, whether to heat or cool the coolant is determined according to whether to heat or cool the coolant at the minimum battery temperature and whether to heat or cool the coolant at the maximum battery temperature.

[0089] For example, if you can Figure 7 As determined in , when the SoC is 28%, the minimum battery temperature corresponds to heating and the maximum battery temperature corresponds to cooling. Figure 6 The diagram shown determines that the coolant should be heated for optimal temperature management of the battery.

[0090] Accordingly, the coolant may be heated in the battery charging device and the heated coolant may be supplied to the battery, thereby increasing the temperature of the battery.

[0091] In the coolant temperature determination step S40 , a set flow rate and a set temperature may be pre-stored according to a determination to heat or cool the coolant.

[0092] In other words, the flow rate and temperature of the coolant can be preset according to whether the battery is heated or cooled, so that the coolant can be supplied to the battery of the vehicle through the battery charging device at an optimal flow rate and temperature.

[0093] For example, when it is determined to cool the battery, the flow rate of the coolant can be set to 25 liters per minute (LPM) and the temperature of the coolant can be set to 15° C. Alternatively, when it is determined to heat the battery, the flow rate of the coolant can be set to 25 LPM and the temperature of the coolant can be set to 60° C. The flow rate and temperature of the coolant can be optimized and set in various ways according to the specifications of the battery and the charging specifications.

[0094] In the coolant temperature determination step S40 , when the heating condition is determined based on the minimum battery temperature and the cooling condition is determined based on the maximum battery temperature, heating or cooling may be determined by comparing the maximum battery temperature with a preset safety temperature.

[0095] The safety temperature is a temperature at which the charging performance of the battery decreases. When the maximum battery temperature is higher than the safety temperature, the charging efficiency of the battery decreases. However, if the battery temperature is lower than the safety temperature, the maximum battery temperature and the safety temperature are compared to determine whether to heat or cool the battery while ensuring the battery charging efficiency.

[0096] In other words, in the coolant temperature determination step S40 , when the maximum battery temperature is lower than the safe temperature, it is determined that the coolant is heated.

[0097] When the maximum battery temperature is lower than the safety temperature, the battery charging efficiency has been ensured, so the temperature of the coolant is increased so that the battery can be heated, thereby maintaining the battery charging efficiency. This is used to prioritize the battery charging speed, and even when it is determined that the maximum battery temperature should be lowered, the battery heating is maintained by further comparing the maximum battery temperature with the safety temperature, thereby ensuring the battery charging efficiency.

[0098] In addition, in the coolant temperature determination step S40 , when the maximum battery temperature is higher than the safe temperature, it is determined that the coolant is to be cooled.

[0099] When the maximum battery temperature is higher than the safe temperature, the battery charging efficiency is reduced and the battery may be damaged. Accordingly, if the maximum battery temperature is higher than the safe temperature, the cooled coolant is supplied to the battery to stabilize the temperature of the battery, thereby preventing damage to the battery.

[0100] In the step S30 of estimating the battery temperature, a predicted temperature is further estimated based on the vehicle information and the charging device information, and the predicted temperature is the battery temperature when the SoC is the set SoC. The set SoC is the SoC at which the battery charging efficiency is reduced, which can be set to 80%, and can be set to various values ​​according to the specifications of the battery. The predicted temperature is the predicted battery temperature when the SoC is the set SoC, and can be derived through machine learning based on the vehicle information and the battery charging device information.

[0101] In addition, in the coolant temperature determination step S40 , the optimal set temperature derived in advance when the SoC is the set SoC is compared with the predicted temperature to determine whether the coolant is overcooled or overheated.

[0102] The optimal set temperature is a battery temperature that ensures battery efficiency when the SoC is the set SoC, and can be derived in advance through experiments and stored.

[0103] Accordingly, if Figure 8 As shown, the predicted temperature is compared with the optimal set temperature, and when the predicted temperature is lower than the optimal set temperature, it is determined that the coolant is overcooled. In this case, it is determined to increase the temperature of the coolant.

[0104] In other words, when the predicted temperature is lower than the optimal set temperature, it is determined that the battery may be overcooled due to the decrease in the temperature of the battery caused by the supply of the coolant during battery charging. Accordingly, the temperature of the coolant supplied from the battery charging device is increased to prevent overcooling of the battery when the SoC reaches the set SoC.

[0105] In the coolant temperature determination step S40 , when it is determined that the battery is overcooled and a heating condition is confirmed based on the current minimum battery temperature, the coolant is heated.

[0106] In other words, when it is determined that the battery is overcooled, when the minimum battery temperature corresponds to the heating condition, the current battery temperature is a low temperature at which the charging efficiency is reduced, and thus heated coolant is supplied to the battery to ensure the battery charging efficiency.

[0107] In addition, in the coolant temperature determination step S40, when it is determined that the battery is overcooled, when it is confirmed that the current maximum battery temperature corresponds to the cooling condition, the maximum battery temperature is compared with a preset safety temperature. In addition, when the maximum battery temperature is lower than the preset safety temperature, the coolant is heated, and when the maximum battery temperature is higher than the preset safety temperature, the coolant is cooled.

[0108] In other words, even in the case where it is determined that the battery is overcooled, when the maximum battery temperature is lower than the safe temperature, the coolant is heated so as to maintain a temperature that optimizes the battery charging efficiency.

[0109] Furthermore, if the maximum battery temperature is higher than a safe temperature, the coolant supplied to the battery is cooled to prevent overheating of the battery.

[0110] In the coolant temperature determination step S40 , if the predicted temperature is higher than the optimal set temperature, it is determined that the battery is overheated, and it is determined to cool the coolant.

[0111] In other words, when the predicted temperature is higher than the optimal set temperature, it is determined that the battery may be overheated due to the increase in the temperature of the battery due to the supply of the battery coolant during battery charging. Accordingly, the coolant supplied from the battery charging device is cooled to prevent overheating when the SoC reaches the set SoC.

[0112] In the coolant temperature determination step S40 , when the heating condition is determined based on the current minimum battery temperature, the coolant is heated even when it is determined that the battery is overheated.

[0113] In other words, when the minimum battery temperature corresponds to the heating condition, the current battery temperature is a low temperature at which the charging efficiency is reduced, and therefore when it is determined that the battery is overcooled, heated coolant is supplied to the battery to ensure the battery charging efficiency.

[0114] In addition, in the coolant temperature determination step S40, when it is determined that the battery is overheated, the heat pump or heating is checked. In addition, when the heat pump is operated or heating is performed, the predicted temperature is compared with a preset safety temperature, and when the predicted temperature is lower than the safety temperature, the coolant is heated.

[0115] This is to utilize the heat of the battery to operate the heat pump or perform in-vehicle heating. Accordingly, when operating the heat pump or performing in-vehicle heating, even in the case where it is determined that the battery is overheated, if the maximum battery temperature is lower than the safe temperature, the heat of the battery is utilized to implement the heat pump or in-vehicle heating, and heated coolant is provided, thereby maintaining a temperature that optimizes the battery charging efficiency.

[0116] According to the above control logic, Figure 8 The diagram shown is used to control the temperature of the battery and the temperature of the coolant managed in the battery charging device.

[0117] In addition, refer to Fig. 9 As shown in the circuit diagram, when the battery is overcooled, the first radiator, the overcooled battery and the second radiator can be used for condensation of the air conditioner. In addition, when the temperature of the air outside the vehicle is high, the heat of the battery can also be dissipated in the condenser outside the vehicle, so that sufficient heat dissipation can be achieved.

[0118] In addition, refer to Fig.10 As shown in the circuit diagram, when the battery is overheated, the heat source of the battery and the waste heat of the power electronics (PE) can be used instead of the outside air for heat pumping or heating, and the waste heat of the battery can be used regardless of the temperature of the outside air. Thus, sufficient heat source is ensured to achieve heat pump performance and heating efficiency.

[0119] In this way, in the coolant temperature determining step S40 , when the SoC is less than the set SoC, the coolant may be cooled when the current battery temperature is higher than the preset safety temperature.

[0120] In addition, in the coolant temperature determination step S40, when the SoC is equal to or greater than the set SoC, when the current battery temperature is higher than a preset safety temperature, or when the current battery temperature is close to a preset optimal set temperature, the coolant temperature control is released.

[0121] In other words, when the SoC is equal to or greater than the set SoC, battery charging is ensured and charging efficiency is reduced. If the current battery temperature is higher than the safe temperature, the coolant temperature control is released. In this way, by releasing the coolant temperature control, the temperature of the battery is maintained at the current state, thereby reducing energy consumption for ensuring battery charging efficiency.

[0122] In addition, the optimal set temperature is a temperature that ensures battery efficiency when the pre-derived SoC is the set SoC, and when the current battery temperature is close to the optimal set temperature, it is determined that the battery temperature is stable and the coolant temperature control is released.

[0123] As described above, the present invention provides a battery temperature estimation method based on the coolant shared between the vehicle and the battery charging device 200 during battery charging. The method includes: in step S10, collecting vehicle information including battery voltage, state of charge (SoC) and target charging current from the vehicle. The method also includes: in step S20, collecting charging device information including coolant temperature and charging current in the battery charging device 200; in step S30, estimating the minimum temperature and maximum temperature of the battery through machine learning based on the vehicle information and the charging device information; in step S40, determining whether to heat or cool the coolant in the battery charging device 200 based on the data about the minimum temperature and maximum temperature of the battery and the SoC.

[0124] In addition, the battery temperature estimation system according to the present invention includes a vehicle controller 10, which is provided in the vehicle and collects vehicle information including battery voltage, SoC and target charging current. The system also includes a charging device controller 20, which is provided in a battery charging device 200. The charging device controller 20 is configured to: collect charging device information including coolant temperature and charging current in the battery charging device; estimate the minimum temperature and maximum temperature of the battery through machine learning based on the vehicle information and the charging device information; and determine whether to heat or cool the coolant based on the data on the minimum temperature and maximum temperature of the battery and SoC.

[0125] In other words, in the present invention, the temperature of the battery can be derived by applying the battery voltage, SoC, and target charging current as vehicle information and the coolant temperature and charging current as charging device information to machine learning.

[0126] The vehicle controller 10 may further collect information about the outside temperature of the vehicle through an outside temperature sensor.

[0127] In addition, the charging device information collected by the charging device controller 20 may further include the flow rate of the coolant provided to the vehicle during battery charging, the inlet-side coolant temperature, and the outlet-side coolant temperature.

[0128] In this manner, the vehicle controller 10 and the charging device controller 20 may communicate or share information with each other through the electrical connection. The charging device controller 20 may be configured to estimate the battery temperature based on the information and adjust the coolant temperature of the battery charging device 200 .

[0129] Accordingly, the present invention improves charging efficiency by managing the temperature of the high-voltage battery during charging of the high-voltage battery provided in the electric vehicle. This is achieved by sharing the coolant managed by the battery charging device 200 for thermal management of the high-voltage battery arranged outside the vehicle with the coolant of the high-voltage battery of the vehicle 100, thereby supplying the cooled or heated coolant to the high-voltage battery of the vehicle 100.

[0130] In addition, the current battery temperature and the future battery temperature are estimated based on the information of the battery charging device 200 and the information of the vehicle 100. When the battery of the vehicle 100 is charged using the battery charging device 200, the temperature of the coolant is optimized. Thus, the charging efficiency and energy efficiency are improved.

[0131] According to the battery temperature estimation method and system having the above configuration, when charging a high-voltage battery provided in an electric vehicle, the charging efficiency can be improved by managing the temperature of the high-voltage battery. This is achieved by sharing the coolant managed by the battery charging device for thermal management of the high-voltage battery outside the electric vehicle with the coolant of the high-voltage battery of the vehicle, thereby supplying the cooled or heated coolant to the high-voltage battery.

[0132] In addition, the current battery temperature and the future battery temperature can be estimated based on the information about the battery charging device and the vehicle information to optimize the temperature of the coolant when charging the vehicle battery using the battery charging device, thereby improving the charging efficiency and energy efficiency.

[0133] While the present invention has been shown and described in connection with the specific embodiments, it will be apparent to those skilled in the art that the present invention may be modified and varied in various ways without departing from the technical spirit of the invention as provided by the appended claims.

Claims

1. A method for estimating battery temperature based on sharing coolant between a vehicle and a battery charging device during battery charging, the method comprising: Collecting vehicle information, the vehicle information including the voltage, charge state and target charging current of the vehicle battery; collecting charging device information, the charging device information including a coolant temperature and a charging current in a battery charging device; The vehicle's battery temperature is estimated through machine learning based on vehicle information and charging device information.

2. The method according to claim 1, wherein: Estimating battery temperature includes: collecting information about the vehicle and the battery charging device by communicating with a server; When the battery temperature of the vehicle is estimated by the server, the server sends a command signal to control the coolant temperature of the battery charging device accordingly.

3. The method according to claim 1, wherein: Collecting vehicle information or collecting charging device information includes collecting information about external temperature.

4. The method according to claim 1, wherein: Collecting charging device information includes collecting a flow rate, an inlet-side coolant temperature, and an outlet-side coolant temperature of a coolant provided to the vehicle during battery charging.

5. The method according to claim 1, wherein: Estimating the battery temperature further includes estimating a minimum temperature and a maximum temperature of the battery based on the vehicle information and the charging device information.

6. The method according to claim 5, further comprising: The coolant temperature is determined. In the coolant temperature determination, it is determined whether to heat or cool the coolant in the battery charging device based on the data on the minimum and maximum temperatures of the battery and the state of charge derived in the estimated battery temperature.

7. The method according to claim 6, wherein: Determining the coolant temperature further includes pre-storing a set flow rate and a set temperature depending on a result of the determination of whether to heat or cool the coolant.

8. The method according to claim 6, wherein: Determining the coolant temperature further includes: When the heating condition is determined based on the minimum temperature of the battery and the cooling condition is determined based on the maximum temperature of the battery, whether to heat or cool the coolant is determined by comparing the maximum temperature of the battery with a preset safety temperature.

9. The method according to claim 8, wherein: Determining the coolant temperature further includes: when the maximum temperature of the battery is lower than a preset safety temperature, determining to heat the coolant.

10. The method according to claim 8, wherein: Determining the coolant temperature further includes: when the maximum temperature of the battery is higher than a preset safety temperature, determining to cool the coolant.

11. The method according to claim 6, wherein: Estimating the battery temperature further includes: estimating a predicted temperature based on the vehicle information and the charging device information, the predicted temperature corresponding to the battery temperature when the state of charge is a set state of charge; Wherein, determining the coolant temperature further includes: determining whether the battery is overcooled or overheated by comparing a pre-derived optimal set temperature when the state of charge is a set state of charge with the predicted temperature.

12. The method according to claim 11, wherein: Determining the coolant temperature further includes: When the predicted temperature is lower than the optimal set temperature, it is determined that the battery is overcooled; When it is determined that the battery is overcooled, it is determined that the coolant is to be heated.

13. The method according to claim 12, wherein: Determining the coolant temperature further includes: when it is determined that the battery is overcooled and a heating condition is confirmed based on the current minimum battery temperature, determining to heat the coolant.

14. The method according to claim 12, wherein: Determining the coolant temperature further includes: In the case where it is determined that the battery is overcooled, when the current maximum battery temperature is determined to correspond to the cooling condition, comparing the maximum temperature of the battery with a preset safety temperature; When the maximum temperature of the battery is lower than the preset safety temperature, the coolant is heated; When the maximum temperature of the battery is higher than a preset safety temperature, the coolant is cooled.

15. The method according to claim 11, wherein: Determining the coolant temperature further includes: When the predicted temperature is higher than the optimal set temperature, it is determined that the battery is overheated; In the event that the battery is determined to be overheated, the coolant is cooled.

16. The method according to claim 15, wherein: Determining the coolant temperature further includes: determining to heat the coolant when it is determined that the battery is overheated and a heating condition is confirmed based on a current minimum battery temperature.

17. The method according to claim 15, wherein: Determining the coolant temperature further includes: In the case of battery overheating, check whether the heat pump or heating is used; When the heat pump is operating or performing heating, the predicted temperature is compared with the pre-set safety temperature; When the predicted temperature is lower than the safe temperature, it is determined to heat the coolant.

18. The method according to claim 6, wherein: Determining the coolant temperature further includes: when the state of charge is less than a set state of charge and when the current battery temperature is higher than a preset safety temperature, determining to cool the coolant.

19. The method according to claim 6, wherein: Determining the coolant temperature further includes: releasing the coolant temperature control when the power state is greater than or equal to the set power state, when the current battery temperature is higher than a preset safety temperature, or when the current battery temperature is close to a preset optimal set temperature.

20. A method for estimating battery temperature based on sharing coolant between a vehicle and a battery charging device during battery charging, the method comprising: Collecting vehicle information, the vehicle information including the voltage, charge state and target charging current of the vehicle battery; collecting charging device information, the charging device information including a coolant temperature and a charging current in a battery charging device; Estimate the minimum and maximum temperatures of the battery through machine learning based on vehicle information and charging device information; A determination is made whether to heat or cool the coolant in the battery charging device based on data regarding the minimum and maximum temperatures of the battery and the state of charge.

21. A system for estimating battery temperature, the system comprising: A vehicle controller, which is disposed in the vehicle and configured to collect vehicle information, wherein the vehicle information includes a voltage, a state of charge, and a target charging current of a vehicle battery; and A charging device controller is provided in the battery charging device and is configured to: collecting charging device information, the charging device information including a coolant temperature and a charging current in a battery charging device; Estimate the minimum and maximum temperatures of the battery through machine learning based on vehicle information and charging device information; A determination is made as to whether to heat or cool the coolant based on data regarding the minimum and maximum temperatures and the state of charge of the battery.

Images