System and method for charging the battery of a vehicle with an optimized charging current

Abstract

A system and method incorporated into a vehicle electric supply device (EVSE) 102 to facilitate charging a battery 108 of a vehicle 110 with an optimized charging current includes: extracting attributes associated with the battery 108 coupled to the EVSE 102 at a controller 106; and comparing the real-time temperature gradient of the battery 108 with a dynamic reference temperature gradient determined based on the extracted attributes of the battery. Further, the charging current supplied to the battery 108 is regulated by a controller 106 based on the difference between the real-time temperature gradient and the reference temperature gradient. As illustrated in diagram 200, "t1," "t2," and "t3" represent the time available to the user at various times (t user), and “Gradient 1”, “Gradient 2” and “Gradient 3” represent the respective temperature gradients, so that one can see that TG_REF inversely proportional to t user .

Description

TECHNICAL FIELD

[0001] The present disclosure generally relates to the technical field of battery management systems. More particularly, it relates to a system and method for charging a vehicle battery with optimized charging current. BACKGROUND

[0002] Rapid charging of electric vehicle batteries can lead to temperature rises. Elevated temperatures can cause coolers to turn on prematurely, reducing efficiency, and also negatively impact battery health. The trade-off between rapid charging and efficiency / battery health becomes a critical consideration.

[0003] Various efforts have been made in the past to solve the above-mentioned problems. For example, patent document JP4252024B2 discloses a charging method for rechargeable batteries that controls charging by determining whether a temperature rise value of the battery in a predetermined time is equal to or higher than a set temperature rise value. When the charging current value is small, the temperature rise value of the battery is compared with the small set temperature rise value, and the charging current is controlled accordingly.

[0004] Although the cited document discloses a method for controlling the charging current, there is a possibility of finding a better and more efficient solution to overcome the above-mentioned problems and to regulate the charging current of the battery. OBJECTS OF THE INVENTION

[0005] A general object of the present disclosure is to overcome the above-mentioned problems and to efficiently regulate the charging current of a battery.

[0006] An object of the present disclosure is to extend the lifetime of the battery.

[0007] Another object of the present disclosure is to charge the battery with an optimal charging current within the specified time.

[0008] Another object of the present disclosure is to control the temperature gradient of the battery.

[0009] Another object of the present disclosure is to ensure that the required charging current and power are within the EVSE limits. SUMMARY

[0010] Aspects of the present disclosure generally relate to the technical field of battery management systems. In particular, it relates to a system and method for charging a vehicle battery with optimized charging current.

[0011] One aspect of the present disclosure relates to a system equipped with a vehicle electric supply system (EVSE) to enable charging of a vehicle battery with optimized charging current. The system includes a controller configured to: extract one or more attributes associated with the battery coupled to the EVSE; compare the real-time temperature gradient of the battery with a dynamic reference temperature gradient, wherein the reference temperature gradient varies according to the extracted attributes; and, based on a difference between the real-time temperature gradient and the reference temperature gradient, regulate the charging current to be supplied to charge the battery with the optimized charging current.

[0012] In one aspect, the reference temperature gradient may be determined taking into account the initial temperature of the battery, the temperature at which a cooler connected to the battery is activated, and a user-defined period of time for charging.

[0013] In one aspect, the controller may be configured to monitor the value of the charging current, wherein if the value of the charging current exceeds a threshold range, the controller may regulate the charging current within the threshold range.

[0014] In one aspect, the system may be configured to calculate the real-time charging power associated with charging the battery, wherein, if the calculated charging power exceeds the maximum power limit set on the EVSE, the controller may reduce the reference temperature gradient by a predefined factor in one or more cycles, the one or more cycles continuing until the charging power is reduced below the maximum power limit.

[0015] In one aspect, the controller may include a PI controller for regulating the charging current supplied to the battery and maintaining an optimized charging current profile. Battery attributes may be selected from current, voltage, power, initial temperature, cooler activation temperature, and real-time battery temperature.

[0016] According to another aspect, the present disclosure describes a method in a vehicle electric supply device (EVSE) for facilitating charging of a vehicle battery with an optimized charging current. The method includes: extracting, at a controller, one or more attributes associated with the battery coupled to the EVSE; comparing, at the controller, the real-time temperature gradient of the battery with a dynamic reference temperature gradient, wherein the reference temperature gradient varies in accordance with the extracted attributes; and regulating, at the controller, the charging current to be supplied to the battery based on a difference between the real-time temperature gradient and the reference temperature gradient to charge the battery with the optimized charging current.

[0017] In one aspect, the method may include determining the reference temperature gradient taking into account the initial temperature of the battery, the temperature at which a cooler connected to the battery is activated, and a user-defined period of time for charging.

[0018] In one aspect, the method may comprise monitoring the value of the charging current, wherein, if the value of the charging current exceeds a threshold range, the method may further comprise regulating the charging current within the threshold range.

[0019] In one aspect, the method may include calculating the real-time charging power associated with charging the battery, wherein, if the calculated charging power exceeds the maximum power limit set on the EVSE, the method may further include reducing the reference temperature gradient by a predefined factor in one or more cycles, wherein the one or more cycles continue until the charging power is reduced below the maximum power limit.

[0020] In another aspect, the controller may include a PI controller that regulates the charging current supplied to the battery and maintains an optimized charging current profile. Battery attributes may be selected from current, voltage, power, initial temperature, cooler activation temperature, and real-time battery temperature.

[0021] Various objects, features, aspects and advantages of the subject invention will become more apparent from the following detailed description of preferred embodiments together with the accompanying drawings in which like numerals represent like components. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure. Fig. 1 shows an exemplary network architecture of the proposed system for facilitating charging of a vehicle battery with optimized charging current to explain the operation according to an embodiment of the present disclosure. Fig. 2 shows a diagram illustrating the relationship between the user-defined time and the temperature gradient in accordance with an embodiment of the present disclosure. Fig. 3 shows a block diagram illustrating the proposed system in accordance with an embodiment of the present disclosure. Fig. 4 shows an exemplary flowchart illustrating the operation of the proposed system in accordance with an embodiment of the present disclosure. Fig. 5 shows a flowchart illustrating the proposed method for facilitating charging of a vehicle battery with optimized charging current according to an embodiment of the present disclosure. Fig. 6 shows a graph illustrating the change in battery temperature according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0023] The following is a detailed description of the embodiments of the disclosure illustrated in the accompanying drawings. The embodiments are detailed enough to clearly convey the disclosure. However, the detail is not intended to limit foreseeable variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives that fall within the spirit and scope of the present disclosure as defined by the appended claims.

[0024] The embodiments explained here generally relate to the technical field of battery management systems. In particular, they relate to a system and method for charging a vehicle battery with an optimized charging current.

[0025] Referring to Fig. 1, the proposed system 100 (herein interchangeably referred to as system 100) is configured with a vehicle electric supply equipment (EVSE) 102 to enable charging of a battery 108 of an electric vehicle (EV) 110 (herein interchangeably referred to as vehicle 110) with an optimized charging current via an electric vehicle (EV) charger. In one embodiment, the system 100 may also take control of the temperature gradient of the battery 108 by regulating the charging current.

[0026] According to one embodiment, once a vehicle's battery 108 is paired with the EVSE 102, the controller 106 associated with the system 100 may interact with the battery 108 and extract one or more attributes associated with the battery 108, where the attributes may be selected from current, voltage, power, initial temperature, temperature at which the cooler is activated, and real-time temperature of the battery 108. In an exemplary embodiment, the controller 106 may include one or more processors and memory integrated with the vehicle 110 and located in a strategic location within the vehicle 110, such as the head unit (HU) of the vehicle 110. In another case, the centralized electronic control unit (ECU) of the vehicle 110 may function as the controller 106.In another case, the controller 106 may be a special type of controller that is different from the ECU of the vehicle 110.

[0027] In one embodiment, the battery 108 may be electrically coupled to the EVSE 102 via a charging means to enable the flow of charging current from the EVSE 102 to the battery 108. In another embodiment, the battery 108 may be communicatively coupled to the EVSE 102 via the network 104 to enable a handshaking mechanism between the EVSE 102 and the coupled battery 108.

[0028] Furthermore, the control unit 106 can measure the real-time temperature gradient of the battery 108 ( TG_Meas ) with a dynamic reference temperature gradient (T G_REF ), taking the extracted attributes into account. The reference temperature gradient may vary depending on the extracted attributes.

[0029] In an exemplary embodiment, the reference temperature gradient (T G_REF ) based on the initial temperature of the battery (T init ), the temperature at which a cooler connected to the battery is activated ( TChillerON ), and a user-defined charging time (t user ), wherein the user can enter the time available to charge the battery 108 via an HMI device 114, which can be in communication with the controller 106. In an exemplary embodiment, the HMI device 114 can comprise a GUI-based display module or a mobile computing device such as a smartphone, a laptop, and the like, via which the user can select the time available to charge the battery 108. In another embodiment, the dashboard of the vehicle 110 can also serve as the HMI device 114.

[0030] In one implementation, the reference temperature gradient (T G_REF ) should be calculated so that it is proportional to the difference between the temperature at which the refrigeration unit connected to the battery is switched on (T ChillerON ), and the initial temperature of the battery (T init ) and inversely proportional to the user-defined time span (t user ), i.e. - TG_REF=(TChillerON−Tinit) / tuser

[0031] In one embodiment, controller 106 may be configured to monitor the charging current value. If the charging current value exceeds a threshold range (also referred to herein as BMS current limits / BMS limits), controller 106 may actively regulate the charging current within the threshold range.

[0032] In another embodiment, the system 100 may be configured to calculate the real-time charging power associated with charging the battery 108. Whenever the calculated charging power exceeds the maximum power limit set on the EVSE 102, the controller 106 may reduce the reference temperature gradient by a predefined factor in one or more cycles, where the one or more cycles may continue until the charging power is reduced below the maximum power limit.

[0033] In one embodiment, the charging current may be controlled by a PI controller, which may be either part of the controller 106 or configured separately in the vehicle. In one implementation, the PI controller may compensate for the error between TG_REF and the calculated / measured real-time temperature gradient ( TG_Meas) and further regulate the charging current supplied to the battery 108 within the BMS limits.

[0034] If one assumes that TChillerON and T init are constant, one can see from diagram 200 in Fig. 2, observe that TG_REF inversely proportional to t user no matter what situation you are in. As in Fig. 2, “t1”, “t2” and “t3” represent the time available to the user at different times (t user ), and “Gradient 1”, “Gradient 2” and “Gradient 3” for the respective temperature gradients.

[0035] In one embodiment, the controller 106 may communicate with the EVSE 102 and the battery 108 of the vehicle 110 via the network 104. Further, the network 104 may be a wireless network, a wired network, or a combination thereof, which may be implemented as one of various types of networks, such as an intranet, local area network (LAN), wide area network (WAN), internet, and the like. Furthermore, the network 104 may be either a dedicated network or a shared network. The shared network may represent an interconnection of various types of networks that may utilize a variety of protocols, such as Hypertext Transfer Protocol (HTTP), Transmission Control Protocol / Internet Protocol (TCP / IP), Wireless Application Protocol (WAP), and the like.

[0036] In one embodiment, system 100 may be implemented using any one or a combination of hardware components and software components, such as a cloud, a server 112, a computer system, a computing device, a network device, and the like. Furthermore, controller 106 may interact with battery 108 via a website or application that may be located within the proposed system 100. In one implementation, system 100 may be accessed via a website or application that may be configured with any operating system, including, but not limited to, Android™, iOS™, and the like.

[0037] Referring to Fig. 3, the reference temperature gradient (T G_REF ) 302 based on the initial temperature of the battery (T init ), the temperature at which a cooler connected to the battery is activated ( TChillerON), and the loading time, which refers to the user-defined loading period (t user ), together with the EVSE limit. Furthermore, the measured real-time temperature gradient ( TG_Meas ) 304 as feedback from a high-voltage (HV) battery 108. In block 306, the real-time temperature gradient 304 may be compared to the reference temperature gradient. In block 308, the controller 106 may regulate the charging current to be supplied to the battery 108 based on the difference between the real-time temperature gradient and the reference temperature gradient to charge the battery 108 with the optimized charging current.

[0038] The block diagram 400 in Fig. 4 shows the operation of the proposed system 100. In block 402, the system 100 receives inputs, including the temperature at which a cooler connected to the battery is activated ( TChillerON), and the loading time, which refers to the user-defined loading period (t user ), together with EVSE 102 power limits (also referred to here as EVSE power limits).

[0039] In block 404, the system 100 measures the inputs associated with the battery 108, including current, voltage, and temperature of the battery 108. Further, in block 406, the reference voltage gradient is calculated (as explained above).

[0040] In block 408, the power limit of the EVSE is compared with the charging power required by the battery 108.

[0041] In one embodiment, if it is determined that the EVSE power limit is greater than or equal to the charging power required by the battery 108, the PI controller regulates the charging current in block 410, and the regulated charging current value is compared to the BMS current limits in block 412. If it is determined that the charging current is below the BMS current limits, the output of the PI controller is considered in block 414, i.e., the regulated charging current is delivered to the battery 108. Otherwise, the BMS limits are considered in block 416, and the charging current continues to be regulated to remain within the BMS limits.

[0042] In another embodiment, if it is determined that the EVSE power limit is lower than the charging power required by the battery 108, in block 418 the reference temperature gradient is reduced by a predefined factor in one or more cycles, with the one or more cycles continuing until the charging power is reduced below the maximum power limit.

[0043] As in Fig. 5, the proposed method 500 (also referred to herein as method 500) may be implemented in a vehicle electric supply system (EVSE) to enable charging of a vehicle battery with optimized charging current.

[0044] At block 502, method 500 includes extracting, by a controller, one or more attributes associated with the battery coupled to the EVSE. In an exemplary embodiment, the battery attributes may be selected from current, voltage, power, initial temperature, cooler activation temperature, and real-time battery temperature.

[0045] In block 504, the method 500 includes comparing the real-time temperature gradient of the battery with a dynamic reference temperature gradient, wherein the reference temperature gradient varies depending on the extracted attributes.

[0046] In block 506, the method 500 includes controlling the charging current to be supplied to the battery in the controller based on a difference between the real-time temperature gradient and the reference temperature gradient to charge the battery with the optimized charging current.

[0047] In one embodiment, method 500 may include determining the reference temperature gradient considering the initial temperature of the battery, the temperature at which a cooler connected to the battery is activated, and a user-defined period of time for charging.

[0048] In another embodiment, the method 500 may include monitoring the value of the charging current, and if the value of the charging current exceeds a threshold range, the method 500 may include regulating the charging current within the threshold range.

[0049] In another embodiment, method 500 may include calculating the real-time charging power associated with charging the battery. If the calculated charging power exceeds the maximum power limit set on the EVSE, method 500 may further include reducing the reference temperature gradient by a predefined factor in one or more cycles. The one or more cycles may continue until the charging power is reduced below the maximum power limit.

[0050] In one implementation, the controller may include a PI controller to regulate the charging current supplied to the battery and to maintain an optimized charging current profile.

[0051] The diagram 600 in Fig.Figure 6 clearly shows that the temperature rise occurs faster and reaches greater values ​​when using conventional charging technology. However, the proposed system 100 and method 500 regulate the temperature rise based on the time available to the user. A linear temperature rise is possible with the proposed system 100 and / or method 500, which in turn reduces the thermal stress on the HV battery.

[0052] Furthermore, as shown, in the case of TGC - With Power Limit, the temperature may deviate from the linear increase because active EVSE power limits change the reference temperature gradient.

[0053] Furthermore, during conventional charging, the operating efficiency of the cooler of the battery 108 is higher due to the sharp temperature increase of the battery 108, whereas the proposed system 100 and / or method 500, whether with or without a power limiting technique, operates at lower charging currents, resulting in lower thermal stress on the battery and consequently lower cooling efficiency. Therefore, the proposed system 100 and / or method 500 results in higher efficiency compared to conventional charging techniques.

[0054] It should be noted that the term "battery" refers to an arrangement of rechargeable or non-rechargeable batteries and / or cells arranged in the battery 108. The term also refers to a predefined configuration of multiple batteries and / or cells connected together by series and parallel circuits.

[0055] While the foregoing describes various embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope of the invention. The scope of the invention is determined by the following claims. The invention is not limited to the described embodiments, variations, or examples, which are included to enable a person of ordinary skill in the art to make and use the invention when combined with information and knowledge available to the person of ordinary skill in the art. ADVANTAGES OF THE INVENTION

[0056] The present invention overcomes the above-mentioned problems and efficiently controls the battery charging current.

[0057] The present invention increases the longevity of the battery.

[0058] The present invention charges the battery with an optimal charging current within the specified time.

[0059] The present invention controls the temperature gradient of the battery.

[0060] The present invention ensures that the required charging current and power are within the EVSE limits. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 4252024B2

[0003]

Claims

[1] A system (100) equipped with an electric vehicle supply device (EVSE) (102) to facilitate charging of a battery (108) of a vehicle with an optimized charging current, the system (100) comprising: a control device (106) configured to: extract one or more attributes associated with the battery (108) coupled to the EVSE (102); comparing the real-time temperature gradient of the battery (108) with a dynamic reference temperature gradient, wherein the reference temperature gradient varies in accordance with the extracted attributes; and to regulate the charging current to be supplied for charging the battery (108) with the optimized charging current based on a difference between the real-time temperature gradient and the reference temperature gradient. [2] The system (100) of claim 1, wherein the reference temperature gradient is determined taking into account the initial temperature of the battery, the temperature at which a cooler connected to the battery (108) is commissioned, and a user-defined period of time for charging. [3] The system (100) of claim 1, wherein the controller (106) is configured to monitor the value of the charging current, wherein if the value of the charging current exceeds a threshold range, the controller (106) regulates the charging current within the threshold range. [4] The system (100) of claim 1, wherein the system (100) is configured to calculate the real-time charging power associated with charging the battery (108), wherein, if the calculated charging power exceeds the maximum power limit set on the EVSE (102), the controller (106) reduces the reference temperature gradient by a predefined factor in one or more cycles, the one or more cycles continuing until the charging power is reduced below the maximum power limit. [5] The system (100) of claim 1, wherein the controller (106) comprises a PI controller for regulating the charging current supplied to the battery (108) and maintaining an optimized charging current profile; and wherein the attributes of the battery (108) are selected from current, voltage, power, initial temperature, cooler activation temperature, and real-time temperature of the battery (108). [6] A method (500) in an electric vehicle supply device (EVSE) for facilitating charging of a vehicle battery with an optimized charging current, the method (500) comprising: Extracting (502) one or more attributes associated with the battery coupled to the EVSE at a controller; Comparing (504) the real-time temperature gradient of the battery in the control unit with a dynamic reference temperature gradient, wherein the reference temperature gradient changes in accordance with the extracted attributes; and Controlling (506) the charging current to be supplied to the battery at the control unit based on a difference between the real-time temperature gradient and the reference temperature gradient in order to charge the battery with the optimised charging current. [7] The method (500) of claim 6, wherein the method (500) comprises determining the reference temperature gradient taking into account the initial temperature of the battery, the temperature at which a cooler connected to the battery is activated, and a user-defined period of time for charging. [8] The method (500) of claim 6, wherein the method (500) comprises monitoring the value of the charging current, wherein in the event that the value of the charging current exceeds a threshold range, the method (500) further comprises regulating the charging current within the threshold range. [9] The method (500) of claim 6, wherein the method (500) comprises calculating the real-time charging power associated with charging the battery, wherein, if the calculated charging power exceeds the maximum power limit set on the EVSE, the method (500) further comprises reducing the reference temperature gradient by a predefined factor in one or more cycles, the one or more cycles continuing until the charging power is reduced below the maximum power limit. [10] The method (500) of claim 6, wherein the controller comprises a PI controller for regulating the charging current supplied to the battery and maintaining an optimized charging current profile; and wherein the attributes of the battery are selected from current, voltage, power, initial temperature, cooler activation temperature, and real-time battery temperature.

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