TWI811111B - Method of battery cell voltage dynamic regulation - Google Patents

Abstract

A method of battery cell voltage dynamic regulation is used to set a charging threshold voltage of a battery cell of an electronic device, and the method includes the following steps: (a) obtaining a battery cell swelling experimental data through a cell swelling experiment, (b) using the cell swelling experimental data to establish a cell swelling prediction model, (c) writing the cell swelling prediction model into a controller, (d) predicting a swelling condition through user behavior, and (e) adjusting a voltage reduction mechanism in a timely manner according to the swelling condition of the battery cell.

Description

Dynamic battery voltage reduction method

The invention relates to a method for dynamically lowering the battery voltage, in particular to a method for dynamically lowering the battery voltage of an electronic device.

Nowadays, the application of electronic devices is becoming more and more common, especially the electronic devices with built-in batteries are widely used. The reason is that such electronic devices are usually lightweight, portable, and have the characteristics of long battery life. However, the batteries used in such electronic devices are usually lithium batteries. The disadvantage is that the battery is prone to bulge after a long period of use. Especially in the case of extreme user behavior, the time for swelling will be greatly shortened. Taking FIG. 1 as an example for a user behavior diagram, when the user uses it under normal conditions, the battery can usually still be lower than the preset upper limit of swelling rate within the warranty period. However, when the user's behavior is relatively extreme (such as but not limited to using high energy consumption while charging), it is very likely that the battery will not be able to remain below the preset upper limit of swelling rate during the warranty period.

Among them, the current existing battery swelling detection method is nothing more than using additional pressure, displacement and/or swelling force sensors. This detection method must increase the component cost and component power consumption, and cannot reduce the manufacturing cost of the electronic device. Additionally, known technologies typically use batteries The mechanism of voltage reduction is used to delay the battery swelling rate from reaching the preset upper limit of swelling rate. However, the existing depressurization mechanism currently depresses the voltage for a fixed period of time under specific conditions, thereby protecting the battery cells and avoiding swelling. However, the fixed depressurization mode cannot effectively prevent the occurrence of bloating, especially when the user's behavior is relatively extreme.

Therefore, how to design a method for dynamically lowering the battery voltage of an electronic device, so as to avoid additional component cost and component power consumption, and to avoid the situation where the user's behavior is more extreme and cannot effectively prevent the occurrence of swelling, is the creator of this case. A great topic for research.

In order to solve the above problems, the present invention provides a method for dynamically lowering the battery voltage to overcome the problems of the prior art. Therefore, the battery voltage dynamic lowering method of the present invention is used to set the charging threshold voltage of the battery of the electronic device, and the battery voltage dynamic lowering method includes the following steps: (a) setting a specific swelling rate, and obtaining the battery through the swelling rate calculation formula The specific inflation rate calculation formula for the inflation rate to reach the specific inflation rate. (b) The voltage variable influence index curve and the temperature variable influence index curve are obtained based on the swelling rate calculation formula. (c) Set the basic working voltage and the basic working temperature, and obtain the attainment time for the swelling rate to reach the specified swelling rate under the conditions of the basic working voltage and the basic working temperature. (d) Detecting the actual operating voltage and actual operating temperature of the battery through the voltage sensor and the temperature sensor respectively, and counting a plurality of accumulative times of the battery under different actual operating voltages and actual operating temperatures. (e) Convert the complex voltage multiplication values of the actual working voltage and the basic working voltage through the voltage variable influence index curve, and respectively convert the complex number of temperature multipliers of the actual working temperature and the basic working temperature through the temperature variable influence exponential curve value. (f) Calculating a plurality of equivalent times through the voltage multiplier values, the temperature multiplier values and the accumulated times, and summing up the equivalent times to form the total equivalent time. (g) by total equivalent time and Get the current inflation index of the battery at the standard time. (h) Judging whether to lower the charging threshold voltage according to the swelling index.

The main purpose and function of the present invention is to use the voltage and temperature of the battery to estimate the swelling index of the battery through the controller, and dynamically lower the voltage of the battery based on the swelling index of the battery to reduce the occurrence of swelling and provide Better user experience and user security for users.

In order to further understand the technology, means and effects that the present invention adopts to achieve the predetermined purpose, please refer to the following detailed description and accompanying drawings of the present invention. It is believed that the purpose, characteristics and characteristics of the present invention can be obtained from this in depth and For specific understanding, however, the accompanying drawings are provided for reference and illustration only, and are not intended to limit the present invention.

100: Electronic device

1: battery

2: Controller

22: Memory

24: Counter

3: Voltage sensor

4: Temperature sensor

200: charger

Sv: voltage signal

St: temperature signal

Scom: communication signal

Vb: Voltage

(S100)~(S260): Steps

Fig. 1 is a schematic diagram of user behavior; Fig. 2 is a circuit block diagram of an electronic device with a battery voltage dynamic lowering function of the present invention and a charger; Fig. 3A is a flow chart of the method for reducing battery swelling in the present invention; Fig. 3B is this The experimental curves of cell swelling in different charging states at the test temperature of 35°C; Figure 3C is the experimental curves of cell swelling in different charging states at the test temperature of 40°C; Figure 3D is the test temperature of the present invention It is a curve diagram of cell swelling experiments in different charging states at 45°C; Fig. 4 is a method flow chart of the dynamic step-down method of the present invention; FIG. 5A is a graph showing the influence index of voltage variable in the present invention; and FIG. 5B is a graph showing the influence index of temperature variable in the present invention.

Hereby, the technical content and detailed description of the present invention are explained as follows in conjunction with the drawings: Please refer to FIG. 2 for a circuit block diagram of an electronic device with a battery voltage dynamic lowering function of the present invention and a charger, and refer to FIG. 1 for complex cooperation. The electronic device 100 includes a battery 1 and a controller 2 , and the controller 2 is electrically connected to the battery 1 . The charger 200 is electrically connected to the battery 1 and the controller 2 and used for charging the battery 1 . The battery 1 is used to supply the electric power required for the operation of the electronic device 100 , and the controller 2 is used to control the charging of the battery 1 , so as to inform the charger 200 to adjust the charging voltage of the battery 1 based on the usage status of the battery 1 . Specifically, the electronic device 100 may include a plurality of sensors (or detection circuits), and at least include a voltage sensor 3 and a temperature sensor 4 . The voltage sensor 3 is electrically connected to the battery 1 and the controller 2 , and is used to detect the working voltage of the battery 1 and provide a voltage signal Sv to the controller 2 . The temperature sensor 4 is disposed on the cell of the battery 1 and is electrically connected to the controller 2 to detect the working temperature of the battery 1 and provide a temperature signal St to the controller 2 . The controller 2 can usually be a battery management chip for at least receiving the voltage signal Sv and the temperature signal St of the battery 1 to know the state of the battery 1 and to manage the charging mode for the battery 1 based on the state of the battery 1 . After the charger 200 is electrically connected to the battery 1, the controller 2 communicates with the charger 200 through the communication signal Scom, and the conventional charger 200 usually charges the voltage Vb of the battery 1 to the full charge voltage to maintain as much as possible The battery life of the electronic device 100 .

However, due to the battery 1 being used by the user, the battery 1 will inevitably swell. Therefore, the controller 2 of the present invention can provide a voltage reduction mechanism to protect the cells of the battery 1 and reduce the occurrence of swelling. Specifically, due to the situation that the battery 1 bulges and the user's use Habit is closely related, and under normal use, bloating occurs more slowly. However, in extreme cases of user behavior (such as but not limited to playing high-efficiency games while charging, etc.), the bloat usually occurs more quickly. Therefore, the main purpose and efficacy of the present invention is to use the controller 2 to include a battery voltage dynamic lowering function to judge whether to inform the charger 200 to lower the full charge voltage based on user behavior, so as to reduce the occurrence of bulging, and provide Better user experience and user security for users. Among them, the present invention is mainly based on the swelling index of the battery 1 as the basis for the user's behavior. The more extreme the user's behavior, the faster the swelling index usually increases. In contrast, the frequency of full-charge voltage drop is relatively high, which will be further described later.

Refer to FIG. 3A for the flow chart of the method for reducing cell bulging in the present invention, and FIGS. 3B to 3D are graphs of the cell bulging experiments under different conditions in the present invention. In step ( S100 ), the cell swelling test data (curve) of the battery is obtained through the cell swelling test. In Figure 3B~3D, a specific lithium battery was used as the cell swelling experiment, and the experimental conditions are shown in Table 1 below:

In FIG. 3B , the test temperature is 35° C., and the test voltage is 4.4 V, the condition of cell swelling begins to increase significantly after 100 days. Under the condition of the test voltage of 4.35V, the cell bulging condition started to increase significantly after a delay of 164 days. Under the condition of the test voltage of 4.30V, the bulging condition of the battery cell started to increase after a delay of 293 days. In Figure 3C, Under the conditions of the test temperature of 40°C and the test voltage of 4.4V, 4.35V and 4.30V, the cell swelling occurred after 50, 78 and 135 days respectively. Similarly in FIG. 3D , under the conditions of the test temperature of 45° C. and the test voltage of 4.4V, 4.35V and 4.30V, the cell swelling occurred after 35, 50 and 90 days, respectively. Therefore, it can be seen from the curves in Figures 3B~3D that the higher the operating temperature of the battery 1, the faster the cell bulge will occur, and the higher the charging threshold of the battery 1 (that is, the charging threshold voltage) Under the same conditions, the faster the cell bulge also occurs. Therefore, it can be known that the condition of the cell swelling is closely related to the working temperature of the battery 1 and the charging threshold voltage of the battery 1 .

Then, in step ( S120 ), a cell swelling prediction model is established by using the cell swelling experiment data. The present invention mainly utilizes the experimental data of cell swelling, and cooperates with a preset specific swelling rate (for example, but not limited to, the swelling rate is preset as 10%) to establish a cell swelling prediction model, so as to predict when the cell swelling rate will be (eg, but not limited to, days) will reach a certain inflation rate (ie, 10%). Then, in step ( S140 ), the cell swelling prediction model is written into the controller 2 . After the cell bulge prediction model is obtained, the cell bulge prediction model can be written and stored in the controller 2 by means of burning/data transmission, or the memory 22 accessed by the controller 2 can be provided to make the controller 2. The charging threshold voltage can be regulated by the cell swelling prediction model to effectively prevent swelling, especially when the user's behavior is relatively extreme. It is worth mentioning that in step ( S140 ), in addition to writing and storing the cell swelling prediction model in the controller 2 , other data such as parameter setting/operation mode can also be written, and the present invention is not limited thereto. In addition, the memory 22 may/or may not be included in the controller 2 for access by the controller 2 . Wherein, the swelling rate is preset as 10% for illustration only, and can be adjusted to any percentage value according to the needs of users.

Specifically, in step (S160), the controller predicts the bloating situation through the user's behavior. Since it is known from the cell swelling experiment data that the cell swelling condition is closely related to the operating temperature of the battery 1 and the charging threshold voltage of the battery 1, the main feature of the present invention is that the controller 2 only needs to pass By using the sensors 3, 4 (or detection circuit), etc., to detect the operating temperature of the cell of the battery 1 and the operating voltage of the battery 1, it is possible to predict the time when the swelling rate of the battery cell reaches 10% (that is, the swelling rate of the battery 1 time to reach a specific inflation rate).

Finally, in step ( S180 ), the controller adjusts the depressurization mechanism in a timely manner according to the predicted swelling of the battery cell. Since the controller 2 of the present invention can predict the time when the cell inflation rate reaches a specific inflation rate (i.e. 10%), it can accurately evaluate the cell inflation state according to user behavior, and by predicting the cell inflation situation, timely and dynamic Lower the charging threshold voltage to delay the time when the cell expansion rate reaches a specific expansion rate. Since the present invention can delay the time when the cell swelling rate reaches 10% by timely and dynamically reducing the charging threshold voltage, it can reduce the cell swelling Return Material Authorization (RMA, that is, the customer returns the product within the product warranty period. to obtain a refund or replacement and to repair the product) occurs.

Please refer to FIG. 4 which is a flow chart of the method for the dynamic pressure reduction method of the present invention, and refer to FIGS. 2-3D for complex cooperation. Wherein, the flowchart in FIG. 4 mainly describes the detailed operations of steps ( S160 ) to ( S180 ) in FIG. 3A . Step ( S200 ) is equivalent to step ( S160 ), the controller predicts the bloating situation through user behavior. Wherein, the battery 1 usually has an initial full-charge voltage (for example, but not limited to 4.4V~4.5V) when it leaves the factory, and the controller 2 can set the initial setting value of the charging threshold voltage as the initial full-charge voltage, so as to Start from the initial full charge voltage to step down. Then, it is judged whether the swelling state reaches a predetermined value (S220). When the controller 2 judges that the inflation state has reached the predetermined value, the charging threshold voltage is lowered ( S240 ), and the process returns to step ( S200 ). Otherwise, maintain the original charging threshold voltage (S260), and return to step (S200). In this way, the charging threshold voltage can be lowered in a timely and dynamic manner to delay the time when the cell inflation rate reaches a specific inflation rate.

Referring again to FIG. 3A , in step ( S120 ), the establishment of the cell swelling prediction model is mainly to obtain the swelling rate calculation formula that the swelling rate of the battery 1 reaches a specific swelling rate through the swelling rate calculation algorithm. Specifically, the cell inflation prediction model is mainly established through the expansion simulation equation, the Arenis equation, and the battery gas production reaction equation. The expansion simulation equation and the Arenis equation are respectively shown in the following formulas 1~2: initial inflation value + A × e ( R ₀ × t )...(1)

k = A ₀ × e (- Ea/RT )...(2)

Since the gas that causes battery 1 to bulge is mainly CO ₂ , the chemical reaction of the positive electrode is considered to produce gas in the main battery. The reaction formula is as follows: Li _ix CoO ₂ →(1- x ) Li ⁺ +(1- x ) e ⁻ + CoO ₂ ...(3)

3 CoO ₂ → Co ₃ O ₄ + O ₂ ... (4)

Electrolyte solvent ( EC/DMC ) + O ₂ → H ₂ O + CO ₂ ...(5)

Wherein, x in the above formula 3 may represent the state of charge (State of Charge; SOC) of the battery 1 . When the charging threshold voltage of the battery 1 is 4.4V, x is 0.6, when the charging threshold voltage is 4.35V, x is 0.575, and when the charging threshold voltage is 4.3V, x is 0.55. Since the experimental condition is floating charge at a fixed voltage, Equation 3 should be regarded as a reaction balance. In Equation 5, it is empirically said that when the electrolyte contacts O ₂ , the electrolyte is quickly oxidized to produce CO ₂ , so it is deduced that Equation 4 should be the reaction rate-determining step. Therefore, the reaction equilibrium and reaction rate can be organized as the following formulas 6~7: Keq =[ Li ] ^{(1- x )} ×[ CoO ₂ ]/[ Li _{1- x} CoO ₂ ]→[ CoO ₂ ]= Keq × [ Li _{1- x} CoO ₂ ]/[ Li ] ^{(1- x )} ... (6, reaction equilibrium formula)

Reaction rate = k × [ CoO ₂ ] ⁿ ... (7)

Wherein k in formula 7 is a reaction rate constant, and n is a reaction order (Reaction order), which can be 1-3. Therefore, in summary, the gas production rate of battery 1 is expressed by the following formula 8: gas production rate = k × ( Keq × [ Li _{1- x} CoO ₂ ]/[ Li ] ^{(1- x )} ) ⁿ .. .(8)

The constant k brought into the reaction rate can be rewritten as the gas production rate as shown in Equation 8: Gas production rate = A ₀ × e (- Ea/RT ) × ( Keq ×[ Li _{1- x} CoO ₂ ]/[ Li ] ^{(1- x )} ) ⁿ ... (9)

Since the swelling rate of battery 1 is directly proportional to the gas production rate of battery 1, and ideally the swelling rate is equal to the gas production rate, the expansion simulation equation of Equation 1 is rewritten as Equation 9, and Equation 9 is the inflation rate calculation formula. Among them, n should be a first-order reaction based on experience, so n can be set to 1. Since the bulging gas of the battery 1 is mainly CO ₂ and the chemical reaction of the positive electrode is considered as the main consideration, the swelling rate calculation formula is based on the chemical reaction of the positive electrode of the battery 1 . Since the cell inflation prediction model of the present invention is established based on the cell inflation rate reaching a specific inflation rate (such as but not limited to 10%), the time required for the inflation rate to reach a specific inflation rate (i.e. 10%) can be further deduced It is equal to the gas production rate of battery 1 as shown in the following formula (10): ln (the time for the swelling rate to reach a specific swelling rate)=ln( A ₀ × Keq ×[ Li _{1- x} CoO ₂ ])- Ea/RT +( x -1)×ln([ Li ])...(10)

The above formula 10 is the specific inflation rate calculation formula, and ln( A ₀ × Keq ×[ Li _{1- x} CoO ₂ ]) is a constant term, Ea/RT is a temperature variable, ( x -1)×ln([ Li ]) is the voltage variable. Since the swelling of the battery 1 is closely related to the usage habits of the user, and the swelling of the battery 1 is obviously related to the voltage and temperature of the battery 1, it is necessary to obtain temperature variables and voltage variables to predict the swelling rate of the battery cell. Since in Figures 3B~3C, the experimental data of cell swelling is obtained (a simple list is shown in Table 2 below), so the influence of voltage variables in Figure 5A can be obtained by simulating the experimental data of cell swelling with a specific swelling rate calculation formula The exponential graph and the temperature variable influence exponential graph of FIG. 5B. In this way, the establishment of the cell swelling prediction model in step ( S120 ) can be completed, and it can be written into the controller 2 through step ( S140 ). It is worth mentioning that, in one embodiment of the present invention, the cell swelling prediction model can not only be established by the expansion simulation equation, the Arenis equation and the battery gas production reaction equation. Specifically, the establishment of the prediction model is mainly based on the gas production rate of the battery. Therefore, as long as the implementation of the prediction model is established using the concept of the gas production rate of the battery, it should be included in the scope of the present invention.

Then, the controller 2 sets the basic working voltage and the basic working temperature, and obtains the attainment time for the swelling rate to reach a specific swelling rate under the conditions of the basic working voltage and the basic working temperature. Specifically, the controller 2 obtains the data curve of the cell swelling experiment of the battery cell through the cell swelling experiment (ie, Fig. 3B~3D), and obtains the basic working voltage and the standard working temperature under the condition of the basic working voltage and the basic working temperature based on the battery swelling experimental data curve. time (as shown in Table 2). Taking Table 2 as an example, in the present invention, for example but not limited to, the basic operating voltage is set at 4.3V, and the basic operating temperature is set at 35°C, so that the time required for the swelling rate to reach a specific swelling rate (10%) is 342 days. However, the above example is only for illustration, and any voltage and temperature can be set as the basic working voltage and basic working temperature, and this setting can also be written into the controller 2 through step ( S140 ).

In step (S160), the controller 2 predicts the swelling situation through the user's behavior, mainly through the voltage sensor 3 and the temperature sensor 4 respectively detecting the actual operating voltage and the actual operating temperature of the battery 1, and counting the battery 1 Multiple cumulative times under different actual operating voltages and actual operating temperatures. Wherein, the counting work may be implemented by, for example but not limited to, the counter 24 , and the counter 24 may/or may not be included in the controller 2 . Due to the user's usage habits (playing games, surfing the Internet, communicating etc.), will cause power loss and cause the voltage Vb of the battery 1 to drop gradually, and then charge through the charger 200 to make the voltage Vb rise/fall repeatedly. Therefore, under each actual working voltage, the actual working temperature of the cell may be different, and it may even happen that the current actual working voltage has a different actual working temperature. Therefore, the controller 2 counts/accumulates each different actual operating voltage and the actual operating temperature under different actual operating voltages to obtain a plurality of accumulated times under different actual operating voltages and actual operating temperatures. Wherein, the above counting/accumulating results can be recorded in, for example but not limited to, the memory 22 .

Since the controller 2 has set the basic operating voltage, basic operating temperature and standard time in the previous step, and obtained a plurality of cumulative times under different actual operating voltages and actual operating temperatures in step (S160), it can be obtained through FIG. 5A Compared with the curve in FIG. 5B , the actual operating voltage, actual operating temperature, and accumulated time are converted in equal proportions. Specifically, the voltage multiplier value between the actual operating voltage and the basic operating voltage can be obtained through the graph of the influence index of the voltage variable in Figure 5A, and the value of the voltage multiplier between the actual operating voltage and the basic operating voltage can be obtained, and through the graph of the influence index of the temperature variable in Figure 5B, the relationship between the actual operating temperature and the basic operating voltage can be obtained. Temperature multiplier value between temperatures. Therefore, the plurality of actual operating voltages and the plurality of actual operating temperatures can be converted into a plurality of voltage multiplier values and temperature multiplier values. Afterwards, multiple equivalent times are calculated through the voltage multiplier value, the corresponding temperature multiplier value, and the accumulated time.

These equivalent times are the equivalent time converted from the actual working voltage and the basic working voltage to the basic working voltage and basic working temperature, and the calculation method of each equivalent time is mainly through the corresponding voltage multiplier value, temperature multiplier value and It can be obtained by multiplying the cumulative time, but it can be obtained in other ways (for example, but not limited to calculating the product of the voltage multiplier value, temperature multiplier value and the cumulative time, etc.). Finally, the controller 2 sums up these equivalent times to form a total equivalent time, and the total equivalent time corresponds to the working time of the battery 1 at the basic working voltage and the basic working temperature.

Since the controller 2 has set the battery 1 under the basic operating voltage and basic operating temperature, the time for the swelling rate to reach a specific swelling rate (which can be obtained from FIGS. 3B-3D ), and the total equivalent time is also obtained. Therefore, the controller 2 can obtain the current swelling index of the battery 1 through the total equivalent time and the standard reaching time, and judge whether to lower the charging threshold voltage according to the swelling index. When the swelling index is lower than the preset threshold, the controller 2 can delay the time when the swelling ratio of the battery 1 reaches a specific swelling ratio (10%) by lowering the charging threshold voltage. Among them, the inflation index can be the ratio of the total equivalent time to the time to reach the standard, and can be obtained through the quotient of the total equivalent time and the time to reach the standard. However, the inflation index does not exclude that it can be obtained by other methods (such as but not limited to calculating The ratio of the total equivalent time to the standard time gap time (days) etc.).

In the step ( S180 ), the present invention further provides a specific way of lowering the charging threshold voltage. Specifically, as shown in the following table 3 is the step-down stage table of the present invention:

The depressurization stage table includes a plurality of stages (shown in steps from one to ten), and each stage corresponds to a preset predetermined value of inflation index and predetermined value of depressurization range. When the controller 2 judges that the inflation index satisfies a predetermined inflation index value of a certain order, the charging threshold voltage is correspondingly lowered according to the step-down range. It can be seen from the above Table 3 that the step-down range is not reduced proportionally. The reason is that once the battery 1 bulges, its deterioration speed is too fast (as shown in Figure 3B~3D), and the charging must be further reduced. Threshold voltage can effectively achieve the situation of suppressing the swelling speed too fast. Therefore, in the design of the decompression stage table, the difference between the predetermined value of the inflation index from the first stage to the last stage can be a fixed value (fixed difference), and the difference of the step-down range from the first stage to the last stage The value can be an exponential value (exponential difference), or can be designed as another unequal difference.

Taking the above-mentioned implementation as an example, it is assumed that the working conditions of the battery cells and the equivalent number of days are shown in Table 4 below:

Assume that the initial full-charge voltage is 4.4V, and the initial setting value of the charging threshold voltage is set at the initial full-charge voltage. The controller 2 sets the basic operating voltage to 4.3V, and the basic operating temperature to 35°C. From Table 2, it can be seen that the time for the cell swelling rate to reach a specific swelling rate is 342 days. The controller 2 starts to detect and record the usage status of the user, and obtains multiple accumulative times under different actual operating voltages and actual operating temperatures. Then, the actual operating voltage and the actual operating temperature are converted into a voltage multiplier and a temperature multiplier through the curves in FIG. 5A and FIG. 5B . Taking 4.40V and 42°C as examples, the voltage multiplier converted from 4.4V to 4.3V is 2.74, and the temperature multiplier converted from 42°C to 35°C is 2.29. After multiplying 2.74 by 2.29 and the cumulative time (3 days), the equivalent time is 18.8 (days). By analogy, all equivalent times are obtained and summed up to obtain a total equivalent time of 82.5 days. Then divide the total equivalent time (82.5 days) by the time for the cell swelling rate to reach a specific swelling rate (342 days) to obtain the expansion index (0.241). Finally, comparing the expansion index (0.241) with Table 3, it can be seen that the step-down range falls in the second stage, so the controller lowers the charging threshold voltage by 25mV to 4.375V according to the step-down range.

Therefore, the battery 1 of the present invention does not need to use any additional pressure, displacement and/or swelling force sensors, and does not need to use any pressure, displacement and/or pressure of at least one detection point of the battery 1. The step of bulging force, but only by detecting the voltage and temperature of the battery 1, can accurately predict the bulging condition of the battery cell, and judge whether to inform the charger 200 to lower the full charge voltage based on the user's behavior, so as to reduce the occurrence of bulging situation, and provide users with better user experience and user security.

However, the above description is only a detailed description and drawings of preferred embodiments of the present invention, but the features of the present invention are not limited thereto, and are not intended to limit the present invention. The entire scope of the present invention should be applied for as follows The scope of the patent shall prevail, and all embodiments that conform to the spirit of the patent scope of the present invention and its similar changes shall be included in the scope of the present invention, and any person familiar with the art can easily think of it in the field of the present invention Changes or modifications can be covered by the scope of the following patents in this case.

(S200)~(S260): Steps

Claims (10)

A battery voltage dynamic lowering method is used to set a charge threshold voltage of a battery of an electronic device, and the battery voltage dynamic lowering method includes the following steps: setting a specific swelling rate, and obtaining it through a swelling rate calculation formula The bulge rate of the battery reaches a specific bulge rate calculation formula for the specific bulge rate; based on the bulge rate calculation formula, a voltage variable influence index curve and a temperature variable influence index curve are obtained; a basic operating voltage and a basic operating temperature are set, And obtain a standard time for the swelling rate to reach the specified swelling rate under the basic operating voltage and the basic operating temperature conditions; respectively detect the battery in different multiples by a voltage sensor and a temperature sensor Actual working voltage and multiple actual working temperatures, and count the multiple cumulative times of the battery under different actual working voltages and actual working temperatures; convert these actual working voltages and The multiple voltage multiplier values of the basic working voltage, and the multiple temperature multiplier values of the actual working temperature and the basic working temperature are respectively converted through the temperature variable influence index curve; through the voltage multiplier values, the temperature multiplier values and these accumulated times are used to calculate a plurality of equivalent times, and these equivalent times are summed up to form a total equivalent time; a current bulging index of the battery is obtained through the total equivalent time and the standard attainment time; and through the bulging The index judges whether to lower the charging threshold voltage. The method for dynamically lowering battery voltage as described in claim 1 further includes the following steps: setting a step-down stage table, the step-down stage table includes multiple stages, and each stage corresponds to a preset inflation index value and a predetermined value step-down magnitude; and Based on the swelling index satisfying the predetermined value of the swelling index, the charging threshold voltage is correspondingly lowered according to the step-down range. The battery voltage dynamic lowering method as described in claim item 2, wherein the difference between the predetermined value of the inflation index of these stages from the first stage to the last stage is a fixed value, and the step-down range of these stages is changed from the first stage The difference from the first order to the last order is the exponential value. The battery voltage dynamic lowering method as described in Claim 1, wherein the inflation index is the quotient of the total equivalent time and the standard-reaching time. The battery voltage dynamic lowering method as described in Claim 1, wherein the equivalent times are the products of the corresponding voltage multiplier values, the temperature multiplier values, and the accumulated time. The battery voltage dynamic lowering method as described in Claim 1, wherein a swelling rate of the battery is proportional to a gas production rate of the battery, and the calculation formula of the swelling rate is based on a chemical reaction of a positive electrode of the battery. The method for dynamically lowering battery voltage according to claim 6, wherein the inflation rate is equal to the gas production rate. The battery voltage dynamic lowering method as described in claim item 1 further includes the following steps: obtaining a cell swelling test data curve of a cell of the battery through a cell swelling test; obtaining based on the cell swelling test data curve The standard-reaching time under the conditions of the basic working voltage and the basic working temperature. The method for dynamically lowering battery voltage as described in claim 1, wherein the specific inflation rate is 10%. The battery voltage dynamic lowering method as described in Claim 1, wherein the specification of the battery at the factory has an initial full-charge voltage, and the initial setting value of the charging threshold voltage is the initial full-charge voltage.