Method for monitoring state of charge of battery

Abstract

A method of controlling a state of charge (SOC) of a battery is provided. The method includes: defining a first SOC threshold of the battery, the first SOC threshold being greater than zero; and defining a second SOC threshold of the battery, the second SOC threshold being less than a maximum charge capacity of the battery. The first SOC threshold and the second SOC threshold define a battery protection range of charge of the battery based on a predetermined battery protection range of charge associated with the battery. The method further includes setting a first configurable SOC threshold of the battery, the first configurable SOC threshold being at least the first SOC threshold; and setting a second configurable SOC threshold value of the battery, wherein the second configurable SOC threshold value is not greater than the second SOC threshold value and is greater than the first configurable SOC threshold value. A range between the first configurable SOC threshold and the second configurable SOC threshold is defined by a configurable capacity associated with the battery. During charging and / or discharging of the battery, the SOC of the battery is controlled based on the first configurable SOC threshold and the second configurable SOC threshold. Upon receiving an update to the configurable capacity of the battery, the configurable capacity of the battery and the first configurable SOC threshold and the second configurable SOC threshold are updatable.

Description

Technical Field

[0001] The present disclosure relates to a battery, and in particular to the control of the state of charge of the battery. Background Art

[0002] In many applications, it is necessary to know the amount of charge stored in a battery pack. The amount of charge stored in a battery can be expressed as a percentage of the total charge storage capacity of the battery (i.e., 0% to 100%). The amount of charge stored as a percentage of the total battery capacity is often referred to as the battery's state of charge (SOC).

[0003] It is known that the long-term battery health of a rechargeable battery is affected by the way it is charged and discharged. The speed of charging can affect the health of the battery, as can the battery's state of charge. Frequently discharging a battery to a very low or zero state of charge can be detrimental to long-term battery health. Similarly, leaving a battery at 100% state of charge for a period of time can be detrimental to long-term battery health.

[0004] EP-A-4,009,480 discloses a method for managing the state of charge or energy state of a battery in order to achieve optimized aging. Summary of the invention

[0005] According to a first aspect of the present disclosure, a method for controlling the state of charge (SOC) of a battery is provided. The method comprises:

[0006] defining a first SOC threshold of the battery, the first SOC threshold being greater than zero;

[0007] defining a second SOC threshold of the battery, the second SOC threshold being less than a maximum charge capacity of the battery,

[0008] wherein the first SOC threshold and the second SOC threshold define a battery protection charge range of the battery based on a predetermined battery protection charge range associated with the battery;

[0009] Setting a first configurable SOC threshold of the battery, the first configurable SOC threshold being at least the first SOC threshold;

[0010] setting a second configurable SOC threshold for the battery, the second configurable SOC threshold being no greater than the second SOC threshold and greater than the first configurable SOC threshold, wherein a range between the first configurable SOC threshold and the second configurable SOC threshold is defined by a configurable capacity associated with the battery; and

[0011] During charging and / or discharging of the battery, the SOC of the battery is controlled based on the first configurable SOC threshold and the second configurable SOC threshold, wherein

[0012] Upon receiving an update to the configurable capacity of the battery, the configurable capacity of the battery and the first and second configurable SOC thresholds are updateable.

[0013] According to the method of the first aspect, the state of charge of the battery is controlled between two pairs of SOC thresholds. The first SOC threshold and the second SOC threshold define a predetermined battery protection charge range associated with the battery. According to the method of the first aspect, the SOC of the battery is controlled so that the SOC does not drop below these thresholds. Accordingly, the first SOC threshold prevents the battery from being discharged to zero or a very low SOC. The second SOC threshold prevents the battery from being charged to a very high or fully charged (e.g., 100% SOC) capacity. These thresholds prevent the battery from being discharged or charged in a manner that is detrimental to the long-term health of the battery.

[0014] In addition to the predetermined battery protection charge range, the method of the first aspect also provides a configurable capacity to the battery based on the first configurable SOC threshold and the second configurable SOC threshold. Therefore, the battery available for use can be configured (and reconfigured) via the method of the first aspect. In other words, the configurable capacity of the battery defined by the first SOC threshold and the second SOC threshold can be updated without physically changing the battery.

[0015] In some embodiments, the method further includes mapping the SOC of the battery to a user display SOC range. In some embodiments, the first configurable SOC threshold is mapped to a value of 0% SOC indicating the user display SOC range. In some embodiments, the second configurable SOC threshold is mapped to a value of 100% SOC indicating the user display SOC range. In some embodiments, the method further includes outputting the mapped SOC of the battery to a user display. Accordingly, the method of the first aspect can map the configurable capacity of the battery to a user display SOC range. Therefore, the battery charge amount that can be provided to the user (based on the configurable capacity) can be displayed to the user in a simple manner. In addition, any update to the configurable capacity will result in a new first configurable SOC threshold and a second configurable SOC threshold being mapped to the user display SOC range. Therefore, the user display can also be updated without any hardware changes.

[0016] In some embodiments, the position of the configurable capacity defined by the first configurable SOC threshold and the second configurable SOC threshold within the battery protection range is configurable based on a fine-tuning parameter associated with the battery. The fine-tuning parameter may allow the configurable capacity to be optimized within the battery protection range. Specifically, by positioning the configurable capacity closer to the first SOC threshold than the second SOC threshold, the battery may not be charged to a high SOC level. This in turn may increase the life of the battery. By positioning the configurable capacity closer to the second SOC threshold, the voltage that can be provided to the user (and therefore the power output that can be provided to the user) can be increased. Therefore, the user can optimize the configurable capacity to benefit battery life, power output, or balancing approach.

[0017] In some embodiments, upon receiving an update to the fine-tuning parameter, the position of the configurable capacity defined by the first configurable SOC threshold and the second configurable SOC threshold is updateable. Thus, the configurable capacity of the battery can be updated to benefit battery life or power output without requiring any changes to the battery's hardware.

[0018] In some embodiments, the first SOC threshold is at least 5% of the highest charge capacity of the battery. Thus, the first SOC threshold prevents the battery from being discharged to an SOC below about 5% so as to prevent the battery from being discharged in a manner that may harm the life of the battery. In some embodiments, the second SOC threshold is no greater than 95% of the highest charge capacity of the battery. Thus, the second SOC threshold prevents the battery from being charged to an SOC above about 95% so as to prevent the battery from being overcharged in a manner that may harm the life of the battery.

[0019] In some embodiments, the method is performed by a battery management system connected to the battery, and the battery management system controls the SOC of the battery. Therefore, according to the method of the first aspect, the SOC of the battery can be controlled by a battery management system connected to the battery.

[0020] In some embodiments, the battery management system receives an update communication, wherein the update communication causes the configurable capacity of the battery to be updated. That is, the configurable capacity of the battery (and thus the first configurable SOC threshold and the second configurable SOC threshold) may be updated based on a change in the configurable capacity according to the received communication. The battery management system may receive the communication via any suitable data transmission method. For example, in some embodiments, the communication may be received via a wired connection, such as communication with a diagnostic tool or other hardware. In some embodiments, the battery management system receives the update communication via a wireless network, such as a wireless Internet network, a radio telecommunications network, or a wireless personal area network.

[0021] In some embodiments, the battery is provided as part of an electric work vehicle. With respect to an electric work vehicle, it is understood that the electric work vehicle does not include an internal combustion engine. Thus, the battery of the electric work vehicle (which may not be easily accessible depending on the configuration of the work) can be configured (and reconfigured) based on updates to the configurable capacity without having to access the battery.

[0022] In some embodiments, during discharge of the battery, the maximum discharge current of the battery is modified based on the SOC of the battery and the first configurable SOC threshold. In some embodiments, when the SOC of the battery is within the range defined by the first configurable SOC threshold and the second configurable SOC threshold, the maximum discharge current remains unchanged. For example, the battery may have a maximum discharge current level that the battery can output in a steady state without overheating. Such maximum discharge current may be a predetermined value, or calculated from a lookup table based on a known relationship between the SOC, temperature, and maximum discharge current of the battery. When the SOC of the battery is above the first configurable SOC threshold, the method may allow the battery to output 100% of the maximum discharge current that the battery can safely output (i.e., the method does not change the maximum discharge current).

[0023] In some embodiments, when the SOC of the battery is lower than the first configurable SOC threshold, the maximum discharge current is reduced to zero. Therefore, the method according to the first aspect can control the SOC of the battery within the range defined by the configurable capacity. Since the configurable capacity cannot be extended beyond the battery protection range, the method according to the first aspect improves the battery life by reducing or preventing the battery from over-discharging.

[0024] In some embodiments, when the SOC of the battery decreases to less than the first configurable SOC threshold by no more than a first SOC overshoot range, within the first SOC overshoot range of the battery, the maximum discharge current decreases from the maximum discharge current to zero. It should be understood that according to the method of the first aspect, the configurable capacity of the battery that can be provided to the user of the battery is less than the total battery capacity. In some embodiments, the method of the first aspect may provide a first SOC overshoot range to enable the battery to be discharged in a limited manner when the SOC of the battery drops below the first configurable SOC threshold. In practice, once the configurable capacity has been exhausted, the battery may provide some "reserve power" to allow, for example, emergency operations of the battery to be performed. Within the first SOC overshoot range, the maximum discharge output of the battery may decrease from a predetermined value (e.g., 100% of the maximum discharge current) to 0% of the maximum discharge current. Therefore, it should be understood that as the battery is further discharged within the first SOC overshoot range, the current available for use will decrease. Accordingly, by reducing the maximum discharge current available, the power output of the battery is further reduced as the battery is further discharged within the first SOC overshoot range.

[0025] In some embodiments, during charging of the battery, the maximum charge current of the battery is modified based on the SOC of the battery and the second configurable SOC threshold. In some embodiments, when the SOC of the battery is within the range defined by the first configurable SOC threshold and the second configurable SOC threshold, the maximum charge current remains unchanged. Such maximum charge current can be a predetermined value, or calculated from a lookup table based on a known relationship between the SOC, temperature, and maximum charge current of the battery. When the SOC of the battery is below the second configurable SOC threshold, the method may allow the battery to receive 100% of the maximum charge current that the battery can safely receive (i.e., the method does not change the maximum charge current).

[0026] In some embodiments, the amplitude of the maximum charge current may be the same as the maximum discharge current. In other embodiments, the maximum charge current and the maximum discharge current may be different. It should be understood that the principles of controlling the maximum charge current and the maximum discharge current may be applied to controlling the maximum steady-state current of the battery and the maximum pulse current of the battery.

[0027] In some embodiments, when the SOC of the battery is above the second configurable SOC threshold, the maximum charging current is reduced to zero.

[0028] In some embodiments, when the SOC of the battery increases to a level higher than the second configurable SOC threshold by no more than a second SOC overshoot range, within the second SOC overshoot range of the battery, the maximum charging current decreases from the maximum charging current toward zero. Therefore, in some embodiments, the method of the first aspect may provide a second SOC overshoot range to enable the battery to be charged in a limited manner when the SOC exceeds the second configurable SOC threshold.

[0029] According to a second aspect of the present disclosure, a controller for monitoring the state of charge (SOC) of a battery is provided. The controller is configured to:

[0030] defining a first SOC threshold of the battery, the first SOC threshold being greater than zero;

[0031] defining a second SOC threshold of the battery, the second SOC threshold being less than a maximum charge capacity of the battery,

[0032] wherein the first SOC threshold and the second SOC threshold define a battery protection charge range of the battery based on a predetermined battery protection charge range associated with the battery;

[0033] Setting a first configurable SOC threshold of the battery, the first configurable SOC threshold being at least the first SOC threshold;

[0034] setting a second configurable SOC threshold for the battery, the second configurable SOC threshold being no greater than the second SOC threshold and greater than the first configurable SOC threshold, wherein a range between the first configurable SOC threshold and the second configurable SOC threshold is defined by a configurable capacity associated with the battery;

[0035] During charging and / or discharging of the battery, controlling the SOC of the battery based on the first configurable SOC threshold and the second configurable SOC threshold; and

[0036] Upon receiving an update to the configurable capacity associated with the battery, the configurable capacity of the battery and the first and second configurable SOC thresholds are updated.

[0037] It should be understood that the controller may be configured to perform the method of the first aspect of the present disclosure.Therefore, the controller may also be configured to perform any of the optional method features discussed above.

[0038] According to a third aspect of the present disclosure, a computer program product is provided. The computer program product comprises instructions for causing the controller of the second aspect to execute the method of the first aspect.

[0039] According to a fourth aspect of the present disclosure, there is provided a computer-readable storage medium having stored thereon the computer program of the third aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Specific embodiments of the present disclosure will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0041] - Figure 1 shows a schematic diagram of an electric work vehicle;

[0042] - Figure 2 A schematic diagram showing different SOC ranges according to the present disclosure;

[0043] - Figure 3 a graph showing a mapping of actual SOC to mapped SOC according to the present disclosure; and

[0044] - Figure 4 A graph showing the maximum discharge current and the maximum charge current. DETAILED DESCRIPTION

[0045] refer to Figure 1 , an electric working vehicle 100 is provided. The electric working vehicle comprises a (rechargeable) battery (not shown). The battery can be connected to a charging module (not shown) for charging. The electric working vehicle can also comprise a controller for controlling the state of charge of the battery (e.g., a battery management system). As an example, Figure 1 The specific electric work vehicle 100 in the embodiment of the present invention. The electric work vehicle 100 may include any other type of electric work vehicle. Of course, it should be understood that the present disclosure is not limited to batteries for electric work vehicles. For example, the battery according to the present disclosure may be any battery suitable for use in an electric vehicle, or other battery as part of a (rechargeable) power pack for a work site.

[0046] According to the present disclosure, the battery has a state of charge (SOC, which may range from 0% SOC (i.e., fully discharged) to 100% SOC (i.e., fully charged)). According to the present disclosure, the SOC of the battery may range from 0% SOC to 100% SOC. It should be understood that the SOC of the battery cannot drop below 0% SOC and cannot exceed 100% SOC.

[0047] The electric working vehicle may further include a controller (battery management system) configured to control charging and / or discharging of the battery. Figure 1 ) may be configured to perform a method of controlling the SOC of a battery according to the present disclosure, as discussed in more detail below.

[0048] According to an embodiment of the present disclosure, a control system is provided. Figure 1 A method for determining the SOC of a battery of an electric working vehicle. The method comprises: defining a first SOC threshold value (B) of the battery 1 ), the first SOC threshold (B 1 ) is greater than zero (i.e., greater than 0% SOC of the battery). The method further includes: defining a second SOC threshold (B 2 ), the second SOC threshold (B 2 ) is less than the maximum charge capacity of the battery (ie, less than 100% SOC). The first SOC threshold and the second SOC threshold (B 1 , B 2 ) defines a battery protection charge range of the battery based on a predetermined battery protection charge range associated with the battery. Figure 2 The schematic diagram indicates the first SOC threshold and the second SOC threshold (B 1 , B 2 ) and the battery protection charge range, the schematic diagram shows the battery protection charge range relative to the SOC range of the battery (0% SOC to 100% SOC).

[0049] Since the first SOC threshold B 1 and the second SOC threshold B 2 Intended to represent the SOC threshold of the battery, so the first SOC threshold B 1 and the second SOC threshold B 2 can each be represented by a value between 0 and 1.

[0050] The predetermined battery protection charge range and the first SOC threshold and the second SOC threshold (B 1 ,B 2 ) may be stored by the controller or in a memory associated with the controller. The predetermined battery protection charge range and the first SOC threshold and the second SOC threshold (B) may be set based on the characteristics of the battery and the expected operating characteristics of the battery. 1 , B 2 ). Generally speaking, increasing the predetermined battery protection charge range increases the available capacity of the battery. Reducing the predetermined battery protection charge range can reduce the extent to which the battery is charged to a high charge level (i.e., close to 100% SOC) or discharged to a low charge level (i.e., close to 0% SOC), which in turn improves battery life.

[0051] For example, in some embodiments, the first SOC threshold B 1 It can be at least 5% of the maximum charge capacity of the battery. In other words, the first SOC threshold B 1The SOC may be set at at least 5% SOC of the battery. In some embodiments, the first SOC threshold may be at least: 7% SOC, 10% SOC, or 15% SOC.

[0052] For example, in some embodiments, the second SOC threshold B 2 The second SOC threshold value B may not be greater than 95% of the maximum charge capacity of the battery. 2 may be set at an SOC of no greater than 95% SOC of the battery. In some embodiments, the second SOC threshold may be no greater than 92% SOC, 90% SOC, or 85% SOC.

[0053] Therefore, the battery protection charge range can limit the available SOC range. Figure 2 In the diagram, the battery protection charge range is 100% – B 1 –B 2 The SOC range corresponds to B 1 and B 2 Expressed in % SOC. For example, in some embodiments, the battery protection charge range may be approximately: 80%, 85%, or 90% of the capacity of the battery.

[0054] According to this embodiment, the method further comprises: setting a first configurable SOC threshold (C 1 ). The first configurable SOC threshold C 1 At least the first SOC threshold B 1 The method further includes: setting a second configurable SOC threshold C of the battery 2 The second configurable SOC C 2 The threshold is not greater than the second SOC threshold B 2 and is greater than the first configurable SOC threshold C 1 The first configurable SOC threshold C 1 and the second configurable SOC threshold C 2 The range in between is defined by the configurable capacity associated with the battery. Figure 2 The diagram shows that the first configurable SOC threshold C 1 and the second configurable SOC threshold C 2 And the configurable capacity. Therefore, the configurable capacity of the battery is not greater than the capacity limited by the battery protection charge range. By limiting the configurable capacity in this way, the battery can be controlled in such a way that the battery life is improved.

[0055] Since the first configurable SOC threshold C 1 and the second configurable SOC threshold C 2Intended to represent the SOC threshold of the battery, so the first configurable SOC threshold C 1 and the second configurable SOC threshold C 2 Each may be represented by a value between 0 and 1. The configurable capacity may also be represented by a percentage of the battery capacity (ie, a value between 0 and 1).

[0056] In some embodiments, a fine-tuning parameter may be used to specify the position of the configurable capacity within the battery protection range. Thus, the fine-tuning parameter (T) may define the first configurable SOC threshold C 1 and the second configurable SOC threshold C 2 The position is relative to the first SOC threshold B 1 and the second SOC threshold B 2 The fine-tuning parameter (T) may be at least 0 and not greater than 1. The fine-tuning parameter may be used to determine the first configurable SOC threshold C based on the configurable capacity (U). 1 and the second configurable SOC threshold C 2 For example, C can be calculated using the following equation: 1 , C 2 :

[0057] C 1 =max(B 1 ,B 1 +((B 2 –B 1 –U)xT)); and

[0058] C 2 =min(B 2 ,C 1 +U)

[0059] That is, the first configurable SOC threshold is the first SOC threshold B 1 and by B 1 +((B 2 –B 1 Therefore, the first configurable SOC threshold is at least equal to B 1 The second configurable SOC threshold is the second SOC threshold and C 1 Therefore, the second configurable SOC threshold is not greater than B 2 .

[0060] Therefore, it should be understood that the fine-tuning parameter T can be used to move the relative position of the configurable capacity U within the battery protection charge range. For example, when T=1, the second configurable SOC threshold C 2will be positioned so that it is equal to the second SOC threshold B 2 When T=0, the first configurable SOC threshold C 1 will be positioned so that it is equal to the first SOC threshold B 1 .

[0061] In some embodiments, when the fine-tuning parameter is not provided or updated, the fine-tuning parameter may adopt a default value. For example, the default value may be T=0.5, so as to balance the configurable capacity at the center of the battery protection charge range.

[0062] In some embodiments, upon receiving an update to the fine-tuning parameter T, the first configurable SOC threshold C 1 and the second configurable SOC threshold C 2 The position of the defined configurable capacity U within the battery protection range is updateable. For example, the fine-tuning parameter may be increased to move the configurable capacity U to a higher SOC level in order to improve power output. Alternatively, the fine-tuning parameter may be decreased to move the configurable capacity to a lower SOC level in order to improve battery life.

[0063] The method further includes: controlling the SOC of the battery based on the first configurable SOC threshold and the second configurable SOC threshold during charging and / or discharging of the battery. That is, during use (charging or discharging) of the battery, the SOC is maintained within a range defined by the first configurable SOC threshold and the second configurable SOC threshold.

[0064] In some embodiments, the method further includes: outputting the state of charge of the battery to a user display. Figure 1 In some embodiments, the user display may be disposed in the cab of the electric work vehicle. The user display may be configured to indicate the SOC of the battery to a user. In some embodiments, the user display may include a numerical indication of the SOC (e.g., 0% SOC to 100% SOC), or the user display may include a graphical representation of the SOC of the battery (e.g., a series of bar graphs indicating the SOC). In either case, the user display may indicate the SOC of the battery based on an SOC value between 0 and 1 (corresponding to a SOC range of 0% SOC to 100% SOC) provided by the controller.

[0065] In some embodiments, the SOC indicated on the user display may correspond to the charge remaining in the configurable capacity rather than the SOC of the battery. In such cases, the controller may output a mapped SOC value to the user display rather than a value representing the SOC of the battery.

[0066] To output the mapped SOC value, the controller may set the first configurable SOC threshold C 1 to a value indicating 0% SOC of the user display SOC range, and the second configurable SOC threshold C 2 Mapped to a value indicating 100% SOC for the user display SOC range.

[0067] For example, where the user display requires an SOC value between 0 and 1, the controller may map the battery's SOC (S) to a mapped SOC (M) using the following equation:

[0068] M=(S–C 1 ) / U

[0069] Figure 3 The diagram of shows an example of such a mapping.

[0070] In some embodiments, the SOC of the battery may fall outside the SOC range defined by the configurable capacity (see below). In such cases, such values ​​may not be provided to the user display. For example, the mapped SOC may also have the following conditions: In the case of M>1, the mapped SOC output is 1 (i.e., 100% SOC). Similarly, in the case of M<0, the mapped SOC output may be 0.

[0071] The method also allows the configurable capacity of the battery to be updated. Therefore, upon receiving an update to the configurable capacity of the battery, the configurable capacity of the battery and the first configurable SOC threshold and the second configurable SOC threshold are updateable. Therefore, in some embodiments, the method may also include: the controller (battery management system) receives an update communication. Upon receiving the communication, the configurable capacity (U) of the battery is then updated. In some embodiments, the communication may be received via a wireless network. In other words, the controller may be connected to a receiver that receives communications from the wireless network. In other embodiments, the controller may be connected to a diagnostic tool or other computer terminal via a wired connection (e.g., a universal serial bus connection) to receive the communication.

[0072] In some embodiments, controlling the SOC of the battery according to the method of the present disclosure may include: during discharge of the battery, controlling the maximum discharge current of the battery based on the SOC of the battery and the first configurable SOC threshold. For example, a lookup table indicating the maximum discharge current of the battery may be provided. Discharge currents exceeding this magnitude may cause excessive heating of the battery, which is to be avoided. In some embodiments, the maximum discharge current stored in the lookup table may require input of the current SOC and temperature of the battery. According to the method of this embodiment, the controller may control the maximum discharge current of the battery based on the first configurable SOC threshold (C1 ) and the maximum discharge current indicated by the current SOC modification of the battery.

[0073] Figure 4 A diagram showing a method for controlling the maximum discharge current of the battery according to the present disclosure is shown. Figure 4 As shown, a current multiplier is applied to the maximum discharge current. When the SOC of the battery is equal to or higher than a first configurable SOC threshold (C 1 ), the multiplier is 100%. That is, the maximum discharge current amplitude remains unchanged from the value indicated in the lookup table. Below the first configurable SOC threshold (C 1 ), modify the multiplier so as to control and modify the maximum discharge current that can be output by the battery. For example, when the SOC of the battery is lower than the first configurable SOC threshold, the maximum discharge current can be reduced to zero.

[0074] In some embodiments, for a battery whose SOC is less than the first configurable SOC threshold C 1 For any SOC, the multiplier can be zero.

[0075] exist Figure 4 In an embodiment, the method provides a small overshoot of the configurable capacity. That is, the method may allow the SOC of the battery to be discharged to a predetermined amount below the first configurable SOC threshold to assist in operating the electric work vehicle. For example, Figure 4 As shown, a first SOC overshoot range O is provided. 1 Therefore, when the SOC of the battery decreases to a value lower than the first configurable SOC threshold C 1 The lower limit does not exceed the first SOC overshoot range O 1 , within the first SOC overshoot range, the maximum discharge current is modified from 100% of the maximum discharge current to zero (ie, 0% of the maximum discharge current). 1 The multiplier applied to the maximum discharge current decreases from 1 to 0 within 1. Figure 4 In the embodiment of the first overshoot range O 1 In other embodiments, a parabola or other nonlinear relationship may be provided to linearly reduce the multiplier within the first overshoot range. 1 The multiplier may be reduced from 1 to 0 within a range. By reducing the maximum discharge current within this range, the functionality of the electric work vehicle may be limited once the configurable capacity is exhausted. However, the first overshoot range may provide some "reserve power" to allow the electric work vehicle to reach a charging point, for example. The size of the first overshoot range may be updateable, similar to the other parameters discussed above.

[0076] exist Figure 4In the embodiment of the present invention, the first overshoot range O 1 The size of is about 5% of the battery capacity. In other embodiments, the first overshoot range O 1 It may be at least 3%, 5% or 7% of the battery capacity. In some embodiments, when the first overshoot range is provided, the fine-tuning parameter T and / or the configurable capacity U may be adjusted to ensure that the first overshoot range does not exceed the first SOC threshold B. 1 overlapping.

[0077] Figure 4 A diagram of a method for controlling the maximum charging current of the battery according to the present disclosure is also shown. Figure 4 As shown, a current multiplier is applied to the maximum charging current. When the SOC of the battery is equal to or lower than the second configurable SOC threshold (C 2 ), the multiplier is 100%. That is, the maximum charging current amplitude remains unchanged from the value indicated in the lookup table. Above the second configurable SOC threshold (C 2 ), modify the multiplier so as to control and modify the maximum charging current that can be received by the battery. For example, when the SOC of the battery is higher than the second configurable SOC threshold, the maximum charging current can be reduced to zero.

[0078] In some embodiments, for a battery having a SOC greater than the second configurable SOC threshold C 2 For any SOC, the multiplier can be zero.

[0079] In some embodiments, for example, Figure 4 As shown, a second SOC overshoot range O is provided. 2 Therefore, when the SOC of the battery increases to a value greater than the second configurable SOC threshold C 2 The second SOC overshoot range is not more than O 2 When, in the second SOC overshoot range, the maximum charging current decreases from the maximum charging current toward zero. That is, in the second overshoot range O 2 The multiplier applied to the maximum charge current decreases from 1 to 0 within 1. Figure 4 In the embodiment of the second overshoot range O 2 In other embodiments, a parabola or other nonlinear relationship may be provided to reduce the multiplier linearly within the second overshoot range. 2The multiplier may be reduced from 1 to 0 within a range. By reducing the maximum charge current available within the range, the charge of the battery may be slowly ramped down once the battery is charged beyond the configurable capacity. The extra power may provide the electric work vehicle with some extra "reserve power" that may be used by the user or for performing tasks while the electric work vehicle is idling. The size of the second overshoot range may be updateable, similar to the other parameters discussed above.

[0080] exist Figure 4 In the embodiment of the present invention, the second overshoot range O 2 The size of is about 5% of the battery capacity. In other embodiments, the second overshoot range O 2 In some embodiments, when the second overshoot range is provided, the fine-tuning parameter T and / or the configurable capacity U can be adjusted to ensure that the second overshoot range does not exceed the second SOC threshold value B. 2 overlapping.

[0081] Industrial Applicability

[0082] According to the present disclosure, a method and controller for controlling the SOC of a battery are provided. According to the present disclosure, the SOC of the battery is controlled between two pairs of SOC thresholds. The first SOC threshold and the second SOC threshold define a predetermined battery protection charge range associated with the battery. According to the method of the first aspect, the SOC of the battery is controlled so that the SOC does not drop below these thresholds. Accordingly, the first SOC threshold prevents the battery from being discharged to zero or a very low SOC. The second SOC threshold prevents the battery from being charged to a very high or fully charged (e.g., 100% SOC) capacity. These thresholds prevent the battery from being discharged or charged in a manner that is detrimental to the long-term health of the battery.

[0083] In addition to the predetermined battery protection charge range, the method of the first aspect also provides a configurable capacity to the battery based on the first configurable SOC threshold and the second configurable SOC threshold. Therefore, the battery available for use can be configured (and reconfigured) via the method of the first aspect. In other words, the configurable capacity of the battery defined by the first SOC threshold and the second SOC threshold can be updated without physically changing the battery.

[0084] In some embodiments, the battery is provided as part of an electric work vehicle. With respect to an electric work vehicle, it is understood that the electric work vehicle does not include an internal combustion engine. Thus, the battery of the electric work vehicle (which may not be easily accessible depending on the configuration of the work) can be configured (and reconfigured) based on updates to the configurable capacity without having to access the battery.

Claims

1. A method for controlling the state of charge (SOC) of a battery, the method include: defining a first SOC threshold of the battery, the first SOC threshold being greater than zero; defining a second SOC threshold of the battery, wherein the second SOC threshold is less than a maximum charge capacity of the battery, wherein the first SOC threshold and the second SOC threshold define a battery protection charge range of the battery based on a predetermined battery protection charge range associated with the battery; setting a first configurable SOC threshold of the battery, the first configurable SOC threshold being at least the first SOC threshold; setting a second configurable SOC threshold for the battery, the second configurable SOC threshold being no greater than the second SOC threshold and greater than the first configurable SOC threshold, wherein a range between the first configurable SOC threshold and the second configurable SOC threshold is defined by a configurable capacity associated with the battery; and During charging and / or discharging of the battery, the SOC of the battery is controlled based on the first configurable SOC threshold and the second configurable SOC threshold, wherein Upon receiving an update to the configurable capacity of the battery, the configurable capacity of the battery and the first and second configurable SOC thresholds are updateable.

2. The method according to claim 1, further comprising: include: mapping the SOC of the battery to a user display SOC range, wherein the first configurable SOC threshold maps to a value indicative of 0% SOC of the user display SOC range and the second configurable SOC threshold maps to a value indicative of 100% SOC of the user display SOC range; The mapped SOC of the battery is output to a user display.

3. The method according to any one of claims 1 to 2, wherein The position of the configurable capacity defined by the first configurable SOC threshold and the second configurable SOC threshold within a battery protection range is configurable based on a tuning parameter associated with the battery.

4. The method according to claim 3, wherein The position of the configurable capacity defined by the first configurable SOC threshold and the second configurable SOC threshold is updateable upon receiving an update to the trimming parameter.

5. The method according to any one of claims 1 to 4, wherein The first SOC threshold is at least 5% of the maximum charge capacity of the battery; and / or The second SOC threshold is no greater than 95% of the maximum charge capacity of the battery.

6. The method according to any one of claims 1 to 5, wherein A battery management system connected to the battery controls the SOC of the battery.

7. The method according to claim 6, wherein The battery management system receives an update communication, Wherein the update communication causes the configurable capacity of the battery to be updated.

8. The method according to claim 6 or claim 7, wherein The battery management system receives the update communication via a wireless network.

9. The method according to any one of claims 1 to 8, wherein The battery is provided as part of an electric work vehicle.

10. The method according to any one of claims 1 to 9, wherein During discharge of the battery, a maximum discharge current of the battery is modified based on the SOC of the battery and the first configurable SOC threshold.

11. The method according to claim 10, wherein When the SOC of the battery is higher than or equal to the first configurable SOC threshold, the maximum discharge current remains unchanged.

12. The method according to claim 10 or claim 11, wherein When the SOC of the battery is below the first configurable SOC threshold, the maximum discharge current is reduced to zero.

13. The method according to any one of claims 10 to 12, wherein When the SOC of the battery drops below the first configurable SOC threshold by no more than a first SOC overshoot range, the maximum discharge current decreases from the maximum discharge current toward zero within the first SOC overshoot range of the battery.

14. The method according to any one of claims 1 to 13, wherein During charging of the battery, a maximum charging current of the battery is modified based on the SOC of the battery and the second configurable SOC threshold.

15. The method according to claim 14, wherein When the SOC of the battery is lower than or equal to the second configurable SOC threshold, the maximum charging current remains unchanged.

16. A method according to claim 14 or claim 15, wherein When the SOC of the battery is above the second configurable SOC threshold, the maximum charging current is reduced to zero.

17. The method according to any one of claims 14 to 16, wherein When the SOC of the battery increases above the second configurable SOC threshold by no more than a second SOC overshoot range, the maximum charge current decreases from the maximum charge current toward zero within the second SOC overshoot range of the battery.

18. A controller for monitoring the state of charge (SOC) of a battery of an electric work vehicle, the controller being configured to: defining a first SOC threshold of the battery, the first SOC threshold being greater than zero; defining a second SOC threshold of the battery, wherein the second SOC threshold is less than a maximum charge capacity of the battery, wherein the first SOC threshold and the second SOC threshold define a battery protection charge range of the battery based on a predetermined battery protection charge range associated with the battery; setting a first configurable SOC threshold of the battery, the first configurable SOC threshold being at least the first SOC threshold; setting a second configurable SOC threshold for the battery, the second configurable SOC threshold being no greater than the second SOC threshold and greater than the first configurable SOC threshold, wherein a range between the first configurable SOC threshold and the second configurable SOC threshold is defined by a configurable capacity associated with the battery; controlling the SOC of the battery based on the first configurable SOC threshold and the second configurable SOC threshold during charging and / or discharging of the battery; as well as Upon receiving an update to the configurable capacity associated with the battery, the configurable capacity of the battery and the first and second configurable SOC thresholds are updated.

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