Patent Application
20250183388
This application claims priority to Chinese Patent Application No. 202211014128.4, filed with the China National Intellectual Property Administration on Aug. 23, 2022 and entitled “CHARGING AND DISCHARGING MANAGEMENT METHOD”, which is incorporated herein by reference in its entirety.
This application relates to the terminal field, and in particular, to a charging and discharging management method.
A mass energy density and a volumetric energy density of a lithium-ion battery become higher based on a requirement of people on an electronic device such as a mobile phone/notebook computer for lightening and thinning and a long battery life and a requirement of people on an electronic vehicle for a long battery life. Increasing a capacity per gram of a material of a positive or negative electrode is an important measure to improve an endurance ability of the battery. Currently, a capacity per gram of a graphite material is close to a theoretical limit (372 mAh/g), but a capacity per gram of silicon (Si) (where a theoretical limit of the capacity per gram is 4200 mAh/g) is much higher than that of the graphite. In addition, the silicon has advantages in many aspects, such as moderate potential during lithiation and delithiation, abundant reserves, a low price, being environmental and non-poisonous, and a mature preparation process, and is currently considered as an ideal material for replacing the graphite as an active material of the negative electrode of the battery.
However, the silicon has a significant volume effect, and a volume change rate caused by expansion/contraction during repeated lithiation and delithiation is up to 400%. Consequently, during charging/discharging, due to particle pulverization, delamination of an electrode sheet, repeated destruction/repair of a solid electrolyte interface (solid electrolyte interface, SEI), and the like, active lithium ions are continuously consumed, and a by-product layer is formed on a surface, directly leading to a large cycle-capacity attenuation rate and thickness expansion rate of a silicon-anode battery. As a result, a cycle life of the silicon-anode battery is not ideal, and a use requirement on the electronic device is difficult to be satisfied.
According to a first aspect, this application provides a charging and discharging management method. The method is applied to an electronic device, and the electronic device includes a battery. The method includes: setting a lower-limit voltage of the battery to a first value at a first moment, where when a voltage of the battery reaches the first value, the battery stops being discharged; and setting the lower-limit voltage of the battery to a second value at a second moment, where the second moment is later than the first moment, the second value is greater than the first value, and when the voltage of the battery reaches the second value, the battery stops being discharged.
When the method provided in the first aspect is implemented, the electronic device may gradually increase the lower-limit voltage of the battery, to suppress a volume change rate of the battery, reduce a loss rate of the battery, and extend a battery life.
When the method provided in the first aspect is implemented, in some embodiments, the first moment corresponds to a first battery cycle of the battery, the second moment corresponds to a second battery cycle of the battery, and the first battery cycle and the second battery cycle are different cycles.
When the method provided in the foregoing embodiment is implemented, the electronic device may increase the lower-limit voltage of the battery in units of a quantity of battery cycles.
When the method provided in the first aspect is implemented, in some embodiments, the second battery cycle is a next cycle of the first battery cycle.
When the method provided in the foregoing embodiment is implemented, a electronic device may increase the lower-limit voltage of the battery each time a battery cycle begins. In this way, the electronic device may more flexibly adjust the lower-limit voltage of the battery, to reduce an attenuation speed of a battery capacity, and extend a battery life.
When the method provided in the first aspect is implemented, in some embodiments, a first quantity of battery cycles exists between the second battery cycle and the first battery cycle.
Refer to an embodiment shown in Table 1. The electronic device may increase the lower-limit voltage once each time after 200 battery cycles are completed. In this way, the electronic device may increase the lower-limit voltage as the cycle passes, to reduce the attenuation speed of the battery capacity, and extend the battery life. In addition, frequent increase behaviors are avoided, to help save energy and extend service duration corresponding to one battery cycle.
When the method provided in the first aspect is implemented, in some embodiments, a voltage difference between the second value and the first value corresponds to a first proportion of a battery capacity.
When the method provided in the foregoing embodiment is implemented, each time increasing the lower-limit voltage, the electronic device may determine an increase amount of the lower-limit voltage based on a voltage difference corresponding to a fixed loss amount of the battery capacity.
When the method provided in the first aspect is implemented, in some embodiments, a capacity retention rate of the battery is a third value in the first battery cycle, and the capacity retention rate of the battery is a fourth value in the second battery cycle. The capacity retention rate is a ratio of a current total charging amount to an initial total charging amount of the battery. The third value is different from the fourth value.
When the method provided in the foregoing embodiment is implemented, the electronic device may determine, based on the current capacity retention rate of the battery, whether to increase the lower-limit voltage of the battery. Refer to an embodiment shown in Table 6. The electronic device may determine to increase the lower-limit voltage when the capacity retention rate of the battery drops from 95% to 94%. In this way, the electronic device may more flexibly adjust the lower-limit voltage of the battery based on the current capacity retention rate of the battery.
When the method provided in the first aspect is implemented, in some embodiments, a first voltage value is preset for the battery. The first voltage value is a minimum value of the lower-limit voltage of the battery, and the first value is greater than or equal to the first voltage value.
When the method provided in the foregoing embodiment is implemented, when beginning to use the battery, the electronic device may set the lower-limit voltage to a minimum value higher than a theoretical lower-limit voltage, to prevent, at the beginning, the battery from being fully discharged, thereby reducing the volume change rate of the battery, and delaying the loss rate of the battery.
When the method provided in the first aspect is implemented, in some embodiments, a second voltage value is preset for the battery. The second voltage value is a maximum value of the lower-limit voltage of the battery, and the second value is less than or equal to the second voltage value.
When the method provided in the foregoing embodiment is implemented, the electronic device does not excessively increase the lower-limit voltage when increasing the lower-limit voltage. When the lower-limit voltage reaches the first voltage value, the electronic device no longer increases the lower-limit voltage. In this way, problem of an excessively low actual available capacity of the battery and a short battery life that are generated because the lower-limit voltage is increased do not occur in the battery, to help improve use experience of a user.
When the method provided in the first aspect is implemented, in some embodiments, a material of a negative electrode of the battery includes one or more of the following: carbon, silicon, tin, and germanium. When the method provided in the foregoing embodiment is implemented, when the material of the negative electrode of the battery includes any one or more of the carbon, silicon, tin, and germanium, the electronic device can obviously suppress the volume change rate of the battery, thereby delaying the loss rate of the battery, and improving a cycle life of the battery.
According to a second aspect, this application provides a charging and discharging management method. The method is applied to an electronic device, and the electronic device includes a battery. The method includes: setting a lower-limit voltage of the battery to a fifth value at a third moment, where when a voltage of the battery reaches the fifth value, the battery stops being discharged; and setting the lower-limit voltage of the battery to a sixth value at a fourth moment, where the fourth moment is later than the third moment, the sixth value is less than the fifth value, and when the voltage of the battery reaches the sixth value, the battery stops being discharged.
When the method provided in the second aspect is implemented, the electronic device may gradually decrease the lower-limit voltage of the battery, so that the battery can maintain an initial discharging amount during one time of discharging as a battery capacity attenuates, thereby alleviating a feeling of a user on attenuation of the battery capacity and improving use experience of the user.
When the method provided in the second aspect is implemented, in some embodiments, the third moment corresponds to a third battery cycle of the battery, the fourth moment corresponds to a fourth battery cycle of the battery, and the third battery cycle and the fourth battery cycle are different cycles.
When the method provided in the foregoing embodiment is implemented, the electronic device may decrease the lower-limit voltage of the battery in units of a quantity of battery cycles.
When the method provided in the second aspect is implemented, in some embodiments, the fourth battery cycle is a next cycle of the third battery cycle.
When the method provided in the foregoing embodiment is implemented, the electronic device may decrease the lower-limit voltage of the battery each time a battery cycle begins. In this way, the electronic device may more flexibly adjust the lower-limit voltage of the battery, to reduce an attenuation speed of a battery capacity, and extend a battery life.
When the method provided in the second aspect is implemented, in some embodiments, a first quantity of battery cycles exists between the fourth battery cycle and the third battery cycle.
Refer to an embodiment shown in Table 8. The electronic device may decrease the lower-limit voltage once each time after 200 battery cycles are completed. In this way, the electronic device may decrease the lower-limit voltage as the cycle passes, to reduce the attenuation speed of the battery capacity, and extend the battery life. In addition, frequent decrease behaviors are avoided, to help save energy and extend service duration corresponding to one battery cycle.
When the method provided in the second aspect is implemented, in some embodiments, a voltage difference between the sixth value and the fifth value corresponds to a first proportion of a battery capacity.
When the method provided in the foregoing embodiment is implemented, each time decreasing the lower-limit voltage, the electronic device may determine a decrease amount of the lower-limit voltage based on a voltage difference corresponding to a fixed loss amount of the battery capacity.
When the method provided in the second aspect is implemented, in some embodiments, a capacity retention rate of the battery is a seventh value in the third battery cycle, and the capacity retention rate of the battery is an eighth value in the fourth battery cycle. The capacity retention rate is a ratio of a current total charging amount to an initial total charging amount of the battery. The seventh value is different from the eighth value.
When the method provided in the foregoing embodiment is implemented, the electronic device may determine, based on a current capacity retention rate of the battery, whether to decrease the lower-limit voltage of the battery. For example, the electronic device may determine to decrease the lower-limit voltage when the capacity retention rate of the battery drops from 95% to 94%. In this way, the electronic device may more flexibly adjust the lower-limit voltage of the battery based on the current capacity retention rate of the battery.
When the method provided in the second aspect is implemented, in some embodiments, a first voltage value is preset for the battery. The first voltage value is a minimum value of the lower-limit voltage of the battery, and the sixth value is greater than or equal to the first voltage value.
The electronic device does not excessively decrease the lower-limit voltage when decreasing the lower-limit voltage. When the lower-limit voltage reaches the first voltage value, the electronic device no longer decreases the lower-limit voltage, to avoid affecting normal work of the battery.
When the method provided in the second aspect is implemented, in some embodiments, a second voltage value is preset for the battery. The second voltage value is a maximum value of the lower-limit voltage of the battery. The fifth value is less than or equal to the second voltage value.
When the method provided in the foregoing embodiment is implemented, the electronic device does not set the lower-limit voltage of the battery to an excessively high voltage, to avoid severely depressing the battery capacity at the beginning, reducing a battery life in one battery cycle periodicity, and affecting use experience of a user.
When the method provided in the second aspect is implemented, in some embodiments, a material of a negative electrode of the battery includes one or more of the following: carbon, silicon, tin, and germanium. When the method provided in the foregoing embodiment is implemented, when the material of the negative electrode of the battery includes any one or more of the carbon, silicon, tin, and germanium, the electronic device can obviously suppress the volume change rate of the battery, thereby delaying the loss rate of the battery, and improving a cycle life of the battery.
According to a third aspect, this application provides an electronic device. The electronic device includes one or more processors and one or more memories. The one or more memories are coupled to the one or more processors. The one or more memories are configured to store computer program code, and the computer program code includes computer instructions. When the one or more processors execute the computer instructions, the electronic device is enabled to perform the method in any one of the first aspect and the possible implementations of the first aspect, or perform the method in any one of the second aspect and the possible implementations of the second aspect.
According to a fourth aspect, an embodiment of this application provides a chip system. The chip system is applied to an electronic device. The chip system includes one or more processors. The processor is configured to invoke computer instructions to enable the electronic device to perform the method in any one of the first aspect and the possible implementations of the first aspect, or perform the method in any one of the second aspect and the possible implementations of the second aspect.
According to a fifth aspect, this application provides a computer-readable storage medium including instructions. When the instructions are run on an electronic device, the electronic device is enabled to perform the method in any one of the first aspect and the possible implementations of the first aspect, or perform the method in any one of the second aspect and the possible implementations of the second aspect.
According to a sixth aspect, this application provides a computer program product including instructions. When the computer program product runs on an electronic device, the electronic device is enabled to perform the method in any one of the first aspect and the possible implementations of the first aspect, or perform the method in any one of the second aspect and the possible implementations of the second aspect.
It may be understood that, the electronic device provided in the third aspect, the chip system provided in the fourth aspect, the computer storage medium provided in the fifth aspect, and the computer program product provided in the sixth aspect are all configured to perform the method provided in this application. Therefore, for beneficial effects that can be achieved therein, refer to the beneficial effects in the corresponding method, and details are not described herein again.
Terms used in the following embodiments of this application are merely intended to describe specific embodiments, but are not intended to limit this application.
As shown in
An ordinate is a thickness of the silicon-anode battery. When SOC=0, the thickness of the silicon-anode battery is denoted as TL. TL≠0. When SOC=A % (A % is a state of charge that a charging amount is slightly greater than 0), the thickness of the battery is denoted as TA. When SOC=1−A % (1−A % is a state of charge that the charging amount is slightly less than 100%), the thickness of the battery is denoted as TB. When SOC=100%, the thickness of the battery is denoted as TU.
In the charging process, the thickness of the battery increases as the charging amount increases, that is, the battery expands. Correspondingly, in the discharging process, the thickness of the battery decreases as the charging amount decreases, that is, the battery contracts. A thickness change of the battery in the charging and discharging process is usually due to a thickness change of a negative electrode sheet. In this case, during repeated lithiation and delithiation, a volume change rate caused by expansion/contraction of the negative electrode is extremely high, directly leading to particle pulverization of the negative electrode, delamination of the electrode sheet, and repeated destruction/repair of an SEI. Consequently, a cycle life of the silicon-anode battery is severely affected.
SOC=0 is an extreme value that the battery can reach in a proper discharging process, and SOC=0 corresponds to a battery voltage of Vmin. Vmin may be referred to as a theoretical lower-limit voltage. In the proper discharging process, the battery voltage is not lower than the theoretical lower-limit voltage. SOC=100% is an extreme value that the battery can reach in a proper charging process, and SOC=100% corresponds to a battery voltage of Vmax. Vmax may be referred to as a theoretical upper-limit voltage. Correspondingly, in the proper charging process, the battery voltage is not higher than the theoretical upper-limit voltage. In other words, Vmin to Vmax is a proper usable voltage window for the battery.
As shown in
If the lower-limit voltage is set to Vmin, and the upper-limit voltage is set to Vb2 (SOC=1−A %), that is, the battery is not fully charged (the upper-limit voltage is limited), after charging/discharging is completed, the thickness change rate of the battery is K2:
If the lower-limit voltage is set to Vb1 (SOC=A %), and the upper-limit voltage is set to Vmax, that is, the battery is not fully discharged (the lower-limit voltage is limited), after charging/discharging is completed, the thickness change rate of the battery is K3:
From a change trend of an SOC curve shown in
K1>K2>K3
In other words, under a charging and discharging management policy of fully charging and fully discharging, a charging/discharging volume change rate of the battery is highest, followed by limiting the upper-limit voltage (sacrificing A % of the capacity). A charging/discharging volume change rate under a charging and discharging management policy of limiting the lower-limit voltage (also sacrificing A % of the capacity) is lowest.
A higher charging/discharging volume change rate of the silicon-anode battery indicates a larger loss to the negative electrode and a shorter cycle life (including a capacity life and an expansion life) of the battery. In view of this, this application provides a charging and discharging management method. When the charging and discharging management method provided in embodiments of this application is implemented, an electronic device 10 may set the lower-limit voltage of the battery to a voltage higher than the theoretical lower-limit voltage, and continuously increase the lower-limit voltage as a battery cycle passes, thereby reducing the charging/discharging volume change rate of the silicon anode as much as possible, and extending a battery life.
S101: Determine a current quantity of cycles of a battery.
When the battery is fully charged initially, a charging amount of the battery is 100%. When the battery supplies power to an external circuit, a battery voltage gradually decreases. Refer to an SOC curve of a discharging segment shown in
After power is completely consumed, the battery stops supplying power to the external circuit. From a user perspective, in this case, the charging amount of the battery is 0. In this case, the battery is connected to a charging circuit and the external circuit operates on the battery. The battery voltage gradually increases until a charging amount of a negative electrode is saturated. Refer to an SOC curve of a charging segment shown in
The foregoing process in which the battery is discharged once and charged once, that is, the process in which the charging amount of the battery changes from 100% to 0 and to 100% again shown in
In this embodiment of this application, when beginning a new battery cycle, an electronic device 10 may dynamically adjust an upper-limit voltage and a lower-limit voltage of the battery based on a quantity of performed battery cycles, thereby avoiding an excessive volume change rate of the battery, to reduce a loss to the battery.
The electronic device 10 may set, based on factors such as the quantity of performed battery cycles and a current actual capacity of the battery, a cycle interval at which the lower-limit voltage is adjusted.
The electronic device 10 may set a quantity of cycles that is 1 to n0 as a first cycle interval, a quantity of cycles that is n0+1 to n1 as a second cycle interval, a quantity of cycles that is n1+1 to n2 as a third cycle interval, and so on. The electronic device 10 may set M cycle intervals. Quantities of battery cycles at different intervals may be the same or different based on different bases for dividing the cycle intervals.
When the electronic device 10 begins the new battery cycle, the electronic device 10 may determine the current quantity of cycles.
S102: When the current quantity of cycles of the battery is from 1 to n0 (the first cycle interval), the electronic device 10 sets the lower-limit voltage to Vmin (a theoretical lower-limit voltage) and sets the upper-limit voltage to Vmax (a theoretical upper-limit voltage). Optionally, at the first cycle interval, the electronic device 10 may alternatively set the lower-limit voltage to Vx, where Vx is higher than Vmin, to reduce the loss to the battery and extend a cycle life of the battery. The theoretical lower-limit voltage is also referred to as a first voltage value.
As the quantity of cycles increases, S103 is performed: When the current quantity of cycles of the battery is from n0+1 to n1 (the second cycle interval), the electronic device 10 increases the lower-limit voltage to Vmin+V0, and maintains the upper-limit voltage at Vmax. In this case, a volume change rate of the battery at the second cycle interval is reduced in comparison with that at the first cycle interval, thereby reducing an attenuation speed of a battery capacity and an expansion speed of a battery thickness, and extending a cycle life of the battery.
S104: When the current quantity of cycles of the battery is from n1+1 to n2 (the third cycle interval), the electronic device 10 increases the lower-limit voltage to Vmin+V0+V1, and maintains the upper-limit voltage at Vmax. S105: The electronic device 10 sequentially increases the lower-limit voltage by analogy as the quantity of cycles increases. In this way, on a basis of maintaining the battery capacity and preventing the battery capacity from being excessively low, the electronic device 10 may gradually reduce the attenuation speed of the battery capacity and the expansion speed of the battery thickness, to extend a cycle life of the battery, thereby extending service duration for a user and improving use experience of the user.
A criterion for the battery life is that a battery capacity reaches a lowest value Cmin for maintaining normal work of a battery, or thickness expansion of the battery reaches a maximum value Tmax for maintaining normal work of the battery.
A higher charging/discharging volume change rate of a silicon-anode battery indicates a larger loss to the battery, that is, a faster attenuation speed of the battery capacity. As shown in
As shown in
If the charging and discharging management method provided in this embodiment of this application is performed, after the battery cycle reaches an interval endpoint value such as n0, n1, and n2, the electronic device 10 may gradually increase the lower-limit voltage of the battery, to reduce the charging/discharging volume change rate, thereby gradually reducing the attenuation speed of the battery capacity, such as S0, S1, and S2. In this case, the change of the battery capacity with the battery cycle is represented by a solid line shown in
As shown in
If the method of gradually increasing the lower-limit voltage of the battery provided in this embodiment of this application is performed, the charging/discharging volume change rate of the battery is gradually reduced, such as P1, P2, and P3. In this case, the change of the battery thickness with the battery cycle is represented by a solid line shown in
In some embodiments, the electronic device 10 may set different cycle intervals of the lower-limit voltage based on a quantity of performed battery cycles. Specifically, the electronic device 10 may set each cycle interval based on a fixed quantity of cycles. For example, the electronic device 10 may designate that 200 consecutive battery cycles is one cycle interval. For example, Table 1 shows an adjustment rule for the cycle interval and the lower-limit voltage.
The battery life is limited, and therefore the cycle interval is also limited. In addition, an increase in the lower-limit voltage causes a decrease in the battery capacity. If the lower-limit voltage is set to an excessively high voltage, the battery capacity is excessively low, and an endurance ability of the battery is poor. As a result, the battery needs to be charged frequently and is inconvenient for using by a user. Therefore, after the quantity of performed battery cycles reaches a quantity, subsequent cycles may be designated as one cycle interval, and the lower-limit voltage of the battery is no longer increased. For example, a 601st cycle and a cycle thereafter may be designated as one cycle interval. Beginning from the 601st cycle, the lower-limit voltages of the battery are all Vmin+300 mV, and the electronic device 10 no longer increases the lower-limit voltage of the battery.
After determining the cycle interval, the electronic device 10 may determine the lower-limit voltage of the battery cycle based on the cycle interval at which a current quantity of cycles is located. For example, when a 1st battery cycle begins, the electronic device 10 may set the lower-limit voltage of the battery to Vmin, where for example, Vmin=3.0 V, and set the upper-limit voltage to Vmax, where for example, Vmax=4.45 V. In a discharging process of the battery, the voltage gradually decreases to Vmin. Then, in a charging process of the battery, the voltage restores to Vmax. Thereafter, in each of a 2nd battery cycle, a 3rd battery cycle, . . . , a 200th battery cycle, the battery is charged and discharged based on Vmin=3.0 V and Vmax=4.45 V.
When the battery begins a 201st battery cycle, the electronic device 10 may increase the lower-limit voltage of the battery. For example, the electronic device 10 may increase the lower-limit voltage of the battery to 3.1 V (V0=100 mV). The electronic device 10 may maintain the upper-limit voltage unchanged. In the discharging process of the battery, when the voltage of the battery decreases to 3.1 V, the battery is no longer discharged. Then, the battery may enter the charging process. In the charging process, the voltage of the battery restores to 4.45 V. Thereafter, the battery enters a 202nd battery cycle and begins to be discharged. In each of a 201st battery cycle, a 202nd battery cycle, . . . , a 400th battery cycle, the battery is charged and discharged based on Vmin+V0=3.1 V and Vmax4.45 V.
When the battery begins a 401st battery cycle, the electronic device 10 continues to increase the lower-limit voltage. For example, the electronic device 10 may increase the lower-limit voltage of the battery to 3.2 V (V1=100 mV), and maintain the upper-limit voltage unchanged. During discharging of the battery, when the voltage of the battery decreases to 3.2 V, the battery stops being discharged. Then, the battery may enter the charging process. In the charging process, the voltage of the battery restores to 4.45 V. Thereafter, the battery enters a 402nd battery cycle and begins to be discharged. In each of a 401st battery cycle, a 402nd battery cycle, . . . , a 600th battery cycle, the battery is charged and discharged based on Vmin+V0+V1=3.2 V and Vmax=4.45 V.
In the foregoing embodiment, the electronic device 10 sets the lower-limit voltage of the battery to Vmin (3.0 V). A moment at which the upper-limit voltage is set to Vmax may be referred to as a first moment, and a moment at which the electronic device 10 increases the lower-limit voltage of the battery to 3.1 V may be referred to as a second moment. The electronic device 10 may set the lower-limit voltage at any moment before a discharging end moment in one cycle. The lower-limit voltage 3.0 V corresponding to the first moment may be referred to as a first value, and the lower-limit voltage 3.1 V corresponding to the second moment is a second value. The 1st battery cycle corresponding to the first moment may be referred to as a first battery cycle, and the 201st battery cycle corresponding to the second moment may be referred to as a second battery cycle. 200 battery cycles exist between the second battery cycle and the first battery cycle. The 200 battery cycles are a first quantity of battery cycles.
It may be understood that the moment at which the electronic device 10 sets the lower-limit voltage of the battery to 3.1 V may be referred to as the first moment, and a moment at which the electronic device 10 increases the lower-limit voltage of the battery to 3.2 V may be referred to as the second moment. In this case, the lower-limit voltage 3.1 V corresponding to the first moment may be referred to as the first value, and the lower-limit voltage 3.2 V corresponding to the second moment is the second value. The 1st battery cycle corresponding to the first moment may be referred to as a first battery cycle, and the 201st battery cycle corresponding to the second moment may be referred to as a second battery cycle.
It can be learned from
As shown in Table 2, the voltage is increased once after one battery cycle. In this case, an increase amount in one time of increasing cannot be excessively high. Otherwise, the lower-limit voltage of the battery is high after several or dozens of battery cycles. In this case, an excessively fast speed of increasing the voltage corresponds to rapid reduction in the battery capacity. Although a battery life is theoretically extended, for a user, user experience may not be as good as that of a natural loss caused by a volume effect.
Therefore, when the adjustment policy shown in Table 2 is implemented, the increase amount that is of the lower-limit voltage and that corresponds to one battery cycle is much less than the increase amount at one cycle interval shown in Table 1. Preferably, the increase amount that is of the lower-limit voltage and that corresponds to one battery cycle may be 1*0.3 mV.
Similarly, the increase in the lower-limit voltage causes the decrease in the battery capacity. Therefore, the lower-limit voltage cannot be limitlessly increased, to ensure a power supply capability of the battery, and prevent the user experience from being affected by an excessively small battery capacity (insufficient endurance and a need for frequent charging). Therefore, the electronic device 10 may further set a highest value of the lower-limit voltage. When the increase amount of the lower-limit voltage reaches the highest value, the electronic device 10 may stop increasing the lower-limit voltage. For example, the highest value may be 3.5 V (where Vmin3.0 V). When (i−1)*0.3 mV>0.5 V, the electronic device 10 may stop increasing the lower-limit voltage.
In the foregoing embodiment, a kth battery cycle may be referred to as the first battery cycle, where 1≤k≤i, and a (k+1)th battery cycle may be referred to as the second battery cycle. After the kth battery cycle begins, a moment at which the electronic device sets the lower-limit voltage to Vmin+(k−1)*0.3 mV may be referred to as the first moment. After the (k+1)th battery cycle begins, a moment at which the electronic device sets the lower-limit voltage to Vmin+k*0.3 mV may be referred to as the second moment. Vmin+(k−1)*0.3 mV is the first value, and Vmin+k*0.3 mV is the second value. The highest value of the lower-limit voltage (3.5 V) may be referred to as a second voltage value.
In the example shown in Table 1, an increment in the lower-limit voltage between every two adjacent cycle intervals is the same. For example, V0=V1=100 mV. Optionally, the increment in the lower-limit voltage may alternatively be different. Refer to Table 3.
As shown in Table 3, V0=200 mV, and V1=100 mV. It can be learned from charging and discharging curves shown in
Further, when the 1st battery cycle begins, the electronic device 10 may further set the lower-limit voltage to a voltage higher than the theoretical lower-limit voltage, that is, Vx≠Vmin. Refer to Table 4.
Vx>Vmin. For example, when Vmin3.0 V, Vx may be 3.1 V. In this way, the battery is not fully charged and fully discharged from the 1st battery cycle, thereby avoiding a high volume change rate in a process in which the voltage is decreased to the theoretical lower-limit voltage, and further improving a cycle life of the battery.
In the example shown in Table 1, an increment in the lower-limit voltage between every two adjacent cycle intervals is the same. For example, V0=V1=100 mV. Optionally, the increment in the lower-limit voltage may alternatively be different, but an increment in a capacity loss is maintained the same, and a corresponding voltage is determined based on the capacity loss. Refer to Table 5.
As shown in Table 5, at the first cycle interval (the 1st battery cycle to the 200th battery cycle), the electronic device 10 may set the lower-limit voltage of the battery to Vmin. In the second cycle interval (the 201st to 400th battery cycle), a capacity loss of 1% is set to increase the lower voltage limit, and the voltage is Vmin+V(1% loss). V(1% loss) refers to a voltage corresponding to a battery capacity of 1%. A relationship between the battery capacity and the voltage is nonlinear. Each time the lower voltage limit is adjusted upward, an increment of the lower voltage limit corresponding to the capacity of 1% is different. A specific value may be determined based on a voltage-capacity SOC relationship in the initial charging and discharging curve. By analogy, the electronic device 10 may determine the lower-limit voltages corresponding to the third and fourth cycle intervals after entering the third and fourth cycle intervals, thereby gradually reducing the charging/discharging volume change rate and extending a cycle life of the battery.
In this embodiment of this application, when the first value is Vmin and the second value is Vmin+V(1% loss), a voltage difference between the first value and the second value, that is, V(1% loss), may be referred to as a voltage corresponding to a first proportion of the battery capacity.
As the charging and discharging process of the battery progresses, the battery capacity gradually decreases. Therefore, in some other embodiments, the electronic device 10 may monitor a current actual capacity of the battery in real time and set, based on the current actual capacity, the cycle interval for adjusting the lower-limit voltage. For example, the electronic device 10 may set a new cycle interval for every 5% decrement in the battery capacity. For example, Table 6 shows another adjustment rule for the cycle interval and the lower-limit voltage.
The capacity retention rate refers to a ratio of a current battery capacity to an initial battery capacity. As shown in Table 3, the capacity retention rate of 100% to 95% may be designated as the first cycle interval, the capacity retention rate of 95% to 90% (excluding 95%) may be designated as the second cycle interval, and the like. When the capacity retention rate is less than 95%, the electronic device 10 may increase the lower-limit voltage by 100 mV, to reduce the charging/discharging volume change rate of the battery, and reduce the attenuation speed of the battery capacity. The electronic device 10 may increase the lower-limit voltage of the battery based on the actual battery capacity by analogy, thereby extending a cycle life of the battery. Similarly, in consideration of use experience of a user, when the capacity retention rate is reduced to a preset value, the electronic device 10 no longer increases the lower-limit voltage. For example, when the capacity retention rate is less than 85%, the lower-limit voltage of the battery is maintained at Vmin+300 mV.
Similarly, in the method of adjusting the lower-limit voltage based on the previous actual capacity shown in Table 6, the electronic device 10 may set the lower-limit voltage at the first cycle interval to a voltage higher than Vmin, and/or the electronic device 10 may adjust the lower-limit voltage more frequently with reference to the method shown in Table 2, and/or the electronic device 10 may gradually reduce the increase amount of the lower-limit voltage with reference to the method shown in Table 3.
When the foregoing charging and discharging management method is implemented, the electronic device 10 may adjust the lower-limit voltage of the battery as the battery cycle passes, to control the charging/discharging volume change rate of the battery, thereby reducing a loss of the silicon anode and extending a battery life.
In the foregoing embodiment, when the third value is any value from 100% to 95% and the fourth value is any value from 95% to 90%, the first value is Vmin and the second value is Vmin+100 mV. When the third value is any value from 95% to 90% and the fourth value is any value from 90% to 85%, the first value is Vmin+100 mV and the second value is Vmin+200 mV.
In some embodiments, the electronic device 10 may alternatively adjust the upper-limit voltage of the battery simultaneously. Refer to Table 7.
As shown in Table 7, the electronic device 10 may gradually reduce the upper-limit voltage of the battery as the battery cycle passes. In this way, the volume change rate of the battery may be further reduced, thereby reducing irreversible damage to the silicon anode caused by volume expansion/contraction during charging/discharging and extending a cycle life of the battery.
For an adjustment amount and an adjustment periodicity that are of a decrease amount of the upper-limit voltage, refer to the specific rule of the increase amount of the lower-limit voltage, and details are not described herein. The electronic device 10 may adjust the upper-limit voltage and the lower-limit voltage synchronously.
Refer to a battery thickness-SOC curve shown in
In some embodiments, an electronic device 10 may alternatively first set a lower-limit voltage to a voltage higher than the theoretical lower-limit voltage Vmin, and then decrease the lower-limit voltage in a subsequent battery cycle, so that the battery can maintain an initial discharging amount in one discharging process when the battery capacity attenuates, thereby alleviating a feeling of a user on attenuation of the battery capacity and improving use experience of the user.
For example, initially, the electronic device 10 may set the lower-limit voltage of the battery to VY, where VY>Vmin, for example, VY=3.5 V; and set the upper-limit voltage to Vmax. For example, Vmax=4.45 V. At the first cycle interval, the battery is charged and discharged based on VY=3.5 V and Vmax=4.45 V.
When the battery begins a 201st battery cycle, the electronic device 10 may decrease the lower-limit voltage of the battery. For example, the electronic device 10 may decrease the lower-limit voltage of the battery VY to 3.4 V. Thereafter, at the second cycle interval, the battery is charged and discharged based on 3.4 V and Vmax=4.45 V. Based on the initially set lower-limit voltage, the electronic device 10 may continuously decrease the lower-limit voltage of the battery by analogy as the battery cycle passes, until the lower-limit voltage reaches the theoretical lower-limit voltage Vmin.
Refer to the method shown in Table 2. In the embodiment (Table 8) in which the lower-limit voltage is decreased, the electronic device 10 may alternatively decrease the lower-limit voltage of the battery each time a new battery cycle begins. Refer to the method shown in Table 3. In the embodiment in which the lower-limit voltage is decreased, a decrease amount by which the electronic device 10 decreases the lower-limit voltage each time may also be different. Refer to the method shown in Table 5. The electronic device 10 may determine the decrease amount based on a capacity loss. Refer to the method shown in Table 6. The electronic device 10 may alternatively determine the decrease amount and the like based on a current capacity retention rate of the battery, and details are not described herein.
In the foregoing embodiment, a moment at which the electronic device 10 sets VY in the 1st battery cycle may be referred to as a third moment. The electronic device 10 may set VY at any moment before a discharging end moment of the cycle. A moment at which the electronic device 10 sets VY−100 mV in the 201st battery cycle may be referred to as a fourth moment. Correspondingly, VY may be referred to as a fifth value, and VY−100 mV may be referred to as a sixth value. It may be understood that, a moment at which the electronic device 10 sets VY−100 mV in the 201st battery cycle may be referred to as the third moment. A moment at which the electronic device 10 sets VY−200 mV in the 401st battery cycle may be referred to as the fourth moment. Correspondingly, VY−100 mV may be referred to as the fifth value, and VY−200 mV may be referred to as the sixth value.
As shown in
The processor 101 may include one or more processing units. For example, the processor 101 may include an application processor (application processor, AP), a modem processor, a graphics processing unit (graphics processing unit, GPU), an image signal processor (image signal processor, ISP), a controller, and a digital signal processor (digital signal processor, DSP), and a baseband processor. Different processing units may be independent devices, or may be integrated into one or more processors. The controller may generate an operation control signal based on instruction operation code and a timing signal, to complete control of instruction fetching and instruction execution. A memory may be further disposed in the processor 101 for storing instructions and data.
The USB interface 102 is an interface that conforms to a USB standard specification, and may be specifically a mini USB interface, a micro USB interface, a USB Type C interface, or the like. The USB interface 102 may be configured to be connected to a charger to charge the electronic device 10, or may be used for data transmission between the electronic device 10 and a peripheral device.
It may be understood that, an interface connection relationship between modules illustrated in this embodiment of this application is merely an example for description, and does not constitute a limitation on a structure of the electronic device 10. In some other embodiments of this application, the electronic device 10 may alternatively use an interface connection manner different from that in the foregoing embodiment, or use a combination of a plurality of interface connection manners.
A material of a negative electrode of the battery 103 is a material that has a significant volume effect such as silicon, tin (Sn), and germanium, and a mixed negative electrode including the material and graphite. For example, the battery 103 may be a silicon-anode (graphite-silicon doped) lithium battery. The battery 103 may supply power to another module of the electronic device 10, such as a processor, to maintain normal work of the electronic device 10. After stored electrical energy of the battery 103 is completely consumed, the battery 103 may receive charging input from the charger through the USB interface 102, to store electrical energy, and then continue to supply power to the electronic device 10.
The battery management module 104 is connected to the USB interface 102, the battery 103, and the processor 101. The battery management module 104 may supply power to the electronic device while charging the battery 103. The battery management module 104 is configured to receive charging input from the charger. The battery management module 104 receives input of the battery 103 to supply power to another module of the electronic device 10 such as the processor 101. The battery management module 104 may further be configured to monitor parameters such as a battery capacity, a quantity of battery cycles, and a battery health status (power leakage and impedance). In some other embodiments, the battery management module 104 may alternatively be disposed in the processor 101.
In this embodiment of this application, when monitoring the battery capacity and the quantity of battery cycles, the battery management module 104 may adjust a lower-limit voltage and/or an upper-limit voltage of the negative electrode to reduce a volume change rate of the material of the negative electrode, so as to reduce a loss to the battery, and extend a cycle life of the battery.
In this embodiment of this application, the electronic device 10 may be a mobile phone, a tablet computer, a desktop computer, a laptop computer, a handheld computer, a notebook computer, an ultra-mobile personal computer (ultra-mobile personal computer, UMPC), a netbook, a cellular phone, a personal digital assistant (personal digital assistant, PDA), an augmented reality (augmented reality, AR) device, a virtual reality (virtual reality, VR) device, an artificial intelligence (artificial intelligence, AI) device, a wearable device, a vehicle-mounted device, a smart home device, and/or a smart city device. A specific type of the electronic device 10 is not specifically limited in this embodiment of this application.
As used in the specification and the claims of this application, a singular expression form, “one”, “a”, “said”, “foregoing”, “the”, or “this”, is intended to also include a plural expression form, unless clearly indicated to the contrary in the context. It should be further understood that, the term “and/or” used in this application indicates and includes any and all possible combinations of one or more of the listed items. As used in the foregoing embodiments, based on the context, the term “when” may be interpreted as a meaning of “if”, “after”, “in response to determining”, or “in response to detecting”. Similarly, based on the context, the phrase “when it is determined” or “if it (the described condition or event) is detected” may be interpreted as a meaning of “if it is determined”, “in response to determining”, “when it (the described condition or event) is detected”, or “in response to detecting (the described condition or event)”.
All or some of the foregoing embodiments may be implemented by using software, hardware, firmware, or any combination thereof. When the software is used for implementation, all or some of the embodiments may be implemented in a form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or some of procedures or functions according to embodiments of this application are generated. The computer may be a general-purpose computer, a dedicated computer, a computer network, or another programmable apparatus. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from one network site, computer, server, or data center to another network site, computer, server, or data center in a wired (such as a coaxial cable, an optical fiber, or a digital subscriber line) or wireless (such as infrared, wireless, or microwave) manner. The computer-readable storage medium may be any available medium accessible by the computer, or a data storage device, such as a server or a data center, integrating one or more usable media. The available medium may be a magnetic medium (for example, a floppy disk, a hard disk, or a magnetic tape), an optical medium (for example, a DVD), a semiconductor medium (for example, a solid-state drive), or the like.
A person of ordinary skill in the art may understand that all or some of the procedures in the methods in the foregoing embodiments may be implemented by using a computer program instructing related hardware. The program may be stored in a computer-readable storage medium. When the program is executed, the procedures in the foregoing method embodiments may be performed. The foregoing storage medium includes any medium that can store program code, such as an ROM, a random access memory (RAM), a magnetic disk, or an optical disc.
The foregoing descriptions are merely specific implementations of the present invention, but are not intended to limit the protection scope of the present invention. Any variation or replacement readily figured out by a person skilled in the art within the technical scope disclosed in the present invention shall fall within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202211014128.4 | Aug 2022 | CN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2023/088874 | 4/18/2023 | WO |
