CN103094630B - Battery management method and system - Google Patents

Abstract

The invention discloses a battery management method and a system, wherein the battery management method comprises the following steps: acquiring acquired voltage values of the battery at different historical moments in the charging or discharging process; predicting a voltage value at a future moment according to the historical moment and the acquired voltage value; and managing the battery according to the predicted voltage value. Through the mode, the charging and discharging process state of the battery can be effectively predicted, so that the problems of overcharge and overdischarge are effectively avoided, the electric quantity and the state of a single battery are predicted according to historical and real-time data, and the events such as balance, overvoltage, undervoltage and the like are effectively predicted.

Description

A battery management method and system

technical field

The invention relates to the technical field of batteries, in particular to a method and system for managing batteries during charging and discharging.

Background technique

During the use of the battery, the battery usually needs to switch between the two states of charging and discharging. Therefore, it is often necessary to detect the state of the battery to determine whether it is necessary to stop charging or discharging the battery to avoid overcharging of the battery. or over-discharge.

However, the existing technology can only measure the voltage of the battery in real time. After measuring the voltage of the battery at the current moment, the relevant processing module manages the battery according to the comparison between the measured voltage value and the threshold value. There is a very big disadvantage, that is, the timeliness is poor. Because, after knowing the current voltage value of the battery, it is often necessary to wait for the judgment of the processing module before taking corresponding actions. Therefore, it may cause overcharging or overdischarging of the battery, and the characteristics and state changes of the battery are inert and continuous. The relevant parameters of the battery are obtained through self-learning, combined with real-time data analysis to predict the relevant trends of battery characteristics.

In order to charge and discharge better, it is usually desirable to be able to predict the state of the battery, so as to control related follow-up actions according to the state that the battery will reach, such as stopping charging, stopping discharging, etc.

Therefore, it is necessary to provide a battery management method and system to solve the problem of poor timeliness of battery management in the prior art.

Contents of the invention

The technical problem mainly solved by the present invention is to provide a battery management method and system, which can effectively predict the charging and discharging process state of the battery, thereby avoiding the problems of overcharging and overdischarging.

In order to solve the above technical problems, a technical solution adopted by the present invention is to provide a battery management method, including: a. Acquiring the collected voltage values at different historical moments during the charging or discharging process of the battery; b. The collected voltage value predicts the voltage value in the future; c. Manage the battery according to the predicted voltage value.

Wherein, in step a, the historical moment includes the current moment.

Wherein, in step b, the voltage value at the future time is predicted by the following formula: X _i+1 =2×X _i -X _i-1 , where X _i+1 is the voltage value at the future time T _i+1 , X _i is the voltage value at the first historical moment T _i , Xi _-1 is the voltage value at the second historical moment T _i-1 , T _i+1 -T _i =T _i -T _i-1 =t,t for a specific time interval.

Wherein, the first historical moment is the current moment.

Wherein, in step b, the voltage value at a future moment is predicted by the least square method.

Another technical solution adopted by the present invention is to provide a battery management system, including: a voltage acquisition module, used to collect the voltage value of the battery at different times in the charging or discharging process; a storage module, used to store different historical moments of electricity The collected voltage value; the processing module is used to predict the voltage value of the future time according to the historical time and the collected voltage value; the management module is used to manage the battery according to the predicted voltage value.

Wherein, the historical moment includes the current moment.

Wherein, the processing module predicts the voltage value at the future moment by the following formula: X _i+1 =2×X _i -X _i-1 , where X _i+1 is the voltage value at the future time T _i+1 , and X _i is the first history The voltage value at time T _i , Xi _-1 is the voltage value at the second historical time T _i-1 , T _i+1 -T _i =T _i -T _i-1 =t, t is a specific time interval.

Wherein, the first historical moment is the current moment.

Wherein, the processing module predicts the voltage value at a future moment by the least square method.

The beneficial effects of the present invention are: different from the prior art, the battery management method and system provided by the present invention can predict the charging and discharging process of the battery according to the voltage values at different historical moments, thereby effectively avoiding the problems of overcharging and overdischarging Problem arises.

Description of drawings

FIG. 1 is a flowchart of a battery management method according to an embodiment of the present invention;

Fig. 2 is the battery charging and discharging simulation curve according to the embodiment of the present invention;

Fig. 3 is a schematic structural diagram of a battery management system according to an embodiment of the present invention.

Detailed ways

Please refer to FIG. 1 , which is a flowchart of a battery management method according to an embodiment of the present invention.

As shown in Figure 1, the battery management method disclosed in the present invention includes the following steps:

S101. Obtain the collected voltage values at different historical moments during the charging or discharging process of the battery.

S102. Predict the voltage value at a future time according to the historical time and the collected voltage value.

S103. Manage the battery according to the predicted voltage value.

In step S101, the historical moment includes the current moment. Moreover, the collected voltage values at different historical moments and the corresponding historical moments are preferably stored in the memory of the corresponding processing module or in other storage devices.

In step S102, the voltage value at a future moment can be predicted by the following formula:

X _i+1 ＝2×X _i -X _i-1 (1)

Among them, Xi ₊₁ is the voltage value at the future time T _i+1 , _Xi is the voltage value at the first historical time T _i , Xi _-1 is the voltage value at the second historical time T _i-1 , and T _i+1 -T _i =T _i -T _i-1 =t, where t is a specific time interval.

In step S103, the charging or discharging of the battery can be stopped according to the predicted voltage value. For example, during the charging process, if the predicted voltage value at a future time exceeds the overcharge threshold, the charging action can be stopped. Among them, if it is predicted that the voltage value at a future time exceeds the over-discharge threshold, the discharge operation can be stopped. Wherein, the overcharge threshold and the overdischarge threshold can be obtained through experiments.

Since various power management chips (PMIC, Power Manage Integrate Circuit) generally use eight-bit (or four-bit) single-chip microcomputers, and the processing capabilities of eight-bit single-chip microcomputers are limited. Therefore, in the case of limited power management chip processing capabilities, the formula can be used (1) Carry out simple prediction function, now referring to Fig. 2 to illustrate its principle as follows:

As shown in Figure 2, it draws the battery charge and discharge simulation curve X(x), as mentioned above, _Xi is the voltage value at the first historical moment T _i , and Xi _-1 is the second historical moment T _i-1 The voltage value at time, T _i+1 -T _i =T _i -T _i-1 =t, t is a specific time interval, assuming that the specific time interval t is very short, so in the curve X(x), when the value of t is very When it is small, a trapezoid is formed by the voltage value X _i-1 at the second historical moment, the voltage value X _i+1 at the future moment and its corresponding historical moments T _i-1 and T _i+1 , and T _i is T _i The midpoint of the line segment formed by _-1 and T _i+1 , according to the knowledge of plane geometry:

X _i ＝(X _i+1 +X _i-1 )/2 (2)

Therefore, formula (1) can be derived from formula 2.

Since the calculation amount of the formula (1) is small, and it can perform a simple prediction function when the specific time interval t is very small, it is very suitable for use when the processing capability of the power management chip is insufficient.

It should be noted that, in a preferred embodiment of the present invention, the first historical moment is preferably the current moment.

Moreover, in step S102, in addition to predicting the voltage value at a future time using the formula disclosed above, since the charging and discharging curve of the battery has a linear relationship, each historical time T _n and voltage value X _n ( n is an integer) to carry out mathematical modeling, and predict the trend of the charge and discharge curve through multiple historical moments and corresponding voltage values, so as to obtain the voltage value at the future moment.

However, this method requires a large amount of computation and requires a high processing capability of the processor, so it is more suitable for use in battery management chips using high-performance processors.

Please refer to FIG. 3 . FIG. 3 is a schematic structural diagram of a battery management system according to an embodiment of the present invention.

As shown in FIG. 3 , the battery management system disclosed in the present invention includes: a voltage acquisition module 201 , a storage module 202 , a processing module 203 and a management module 204 .

Wherein, the voltage collection module 201 is used to collect voltage values of the battery at different moments during charging or discharging.

The storage module 202 is used for storing the collected voltage values at different historical moments during the charging or discharging process.

The processing module 203 is used for predicting the voltage value at a future time according to the historical time and the collected voltage value.

The management module 204 is used for managing the battery according to the predicted voltage value.

In a preferred embodiment of the present invention, the historical moment may include the current moment. Moreover, the storage module 202 may preferably be a memory module, and the collected voltage values at different historical moments and the corresponding historical moments may be stored in the memory module.

Further, the processing module 203 can predict the voltage value at a future moment by the following formula:

X _i+1 ＝2×X _i -X _i-1 (1)

Among them, Xi ₊₁ is the voltage value at the future time T _i+1 , _Xi is the voltage value at the first historical time T _i , Xi _-1 is the voltage value at the second historical time T _i-1 , and T _i+1 -T _i =T _i -T _i-1 =t, where t is a specific time interval.

The management module 204 can stop charging or discharging the battery according to the predicted voltage value. For example, during the charging process, if the predicted voltage value at a future moment exceeds the overcharge threshold, the charging action can be stopped. During the discharging process, If it is predicted that the voltage value at a future moment exceeds the over-discharge threshold, the discharge operation can be stopped. Wherein, the overcharge threshold and the overdischarge threshold can be obtained through experiments.

If the processing capability of the processing module 203 is limited (such as eight or four arithmetic units), formula (1) can be used to carry out simple prediction function, please continue to refer to Fig. 2, now refer to Fig. 2 to illustrate its principle as follows:

As shown in Figure 2, it is the battery charge and discharge simulation curve X(x), as mentioned above, _Xi is the voltage value at the first historical moment T _i , and Xi _-1 is the voltage value at the second historical moment T _i-1. Voltage value, T _i+1 -T _i =T _i -T _i-1 =t, t is a specific time interval, assuming that the specific time interval t is very short, so in the curve X(x), when the value of t is very small In this case, a trapezoid is formed by the voltage value X _i-1 at the second historical moment, the voltage value X _i+1 at the future moment and its corresponding historical moments T _i-1 and T _i+1 , and T _i is T _i-1 The midpoint of the line segment formed with T _i+1 , according to the knowledge of plane geometry:

X _i ＝(X _i+1 +X _i-1 )/2 (2)

Therefore, formula (1) can be derived from formula 2.

Since the calculation amount of the formula (1) is small, and the simple prediction function can be performed when the specific time interval t is small, it is very suitable for the case where the processing capacity of the processing module 203 is limited.

It should be noted that, in a preferred embodiment of the present invention, the first historical moment is preferably the current moment.

In addition, if the computing power is allowed, the processing module 203 can use the formula disclosed above to predict the voltage value at the future time, because the charging and discharging curve of the battery has a linear relationship, it can also use the least square method to calculate each historical time T _n and the voltage value X _n (n is an integer) to carry out mathematical modeling, and predict the direction of the charging and discharging curve through multiple historical moments and corresponding voltage values, so as to obtain the voltage value at a future moment.

However, this method requires a relatively large amount of computation and has high requirements on the processing capability of the processing module 203 , so it is more suitable for use when the processing capability of the processing module 203 is relatively high.

The battery management method and system provided by the present invention can predict the charging and discharging process of the battery according to the voltage values at different historical moments, thereby effectively avoiding the problems of overcharging and overdischarging, and can be applied to new energy products, that is, for battery And energy storage products similar to batteries, such as management systems for lithium-ion batteries, battery management systems for lithium polymer batteries, lead-acid batteries, nickel-cadmium batteries, nickel-hydrogen batteries, super capacitors, and future new energy storage products.

The above is only an embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the description of the present invention and the contents of the accompanying drawings, or directly or indirectly used in other related technical fields, All are included in the scope of patent protection of the present invention in the same way.

Claims (4)

1. A battery management method, comprising: a. Obtain the collected voltage values of the battery at different historical moments during charging or discharging, wherein the historical moments include the current moment; b. Predicting the voltage value at a future time according to the historical time and the collected voltage value, wherein the voltage value at the future time is predicted by the following formula: X _i+1 ＝2×X _i -X _i-1 Among them, Xi ₊₁ is the voltage value at the future time T _i+1 , _Xi is the voltage value at the first historical time T _i , Xi _-1 is the voltage value at the second historical time T _i-1 , and T _i+1 -T _i =T _i -T _i-1 =t, where t is a specific time interval; c. Managing the battery according to the predicted voltage value. 2. The battery management method according to claim 1, wherein the first historical moment is the current moment. 3. A battery management system, comprising: A voltage collection module, configured to collect voltage values of the battery at different historical moments during charging or discharging, wherein the historical moments include the current moment; The storage module is used to store the collected voltage values at different historical moments; A processing module, configured to predict the voltage value at a future time according to the historical time and the collected voltage value, wherein the processing module predicts the voltage value at the future time by the following formula: X _i+1 ＝2×X _i -X _i-1 Among them, Xi ₊₁ is the voltage value at the future time T _i+1 , _Xi is the voltage value at the first historical time T _i , Xi _-1 is the voltage value at the second historical time T _i-1 , and T _i+1 -T _i =T _i -T _i-1 =t, where t is a specific time interval; The management module is configured to manage the battery according to the predicted voltage value. 4. The battery management system according to claim 3, wherein the first historical moment is the current moment.