Battery equalization management method

Abstract

To provide a battery equalization management method capable of improving accuracy and stability of battery equalization.SOLUTION: A battery equalization management method includes: a step S10 of setting an operating time t1 and a stopping time t2 such that t1 / (t1+t2)≥80%; a step S20 of performing a charging / discharging operation on a battery within the operating time t1; a step S30 of interrupting the charging / discharging operation within the stopping time t2 and performing a reverse direction charging / discharging operation on the battery for a predetermined time using a small current; a step S40 of performing, after stabilization of voltage of the battery, voltage collection for the battery; and a step S50 of determining whether or not the battery equalization has been completed on the basis of the collected battery voltage data, and if completed, terminating the present battery equalization operation, but if not, returning to execution of the steps S20 to S40.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to the field of battery equalization technology, and particularly to a battery equalization management method.

Background Art

[0002] With the continuous development of new energy vehicles and the continuous improvement of the market share of new energy vehicles, battery equalization devices for new energy vehicles have also emerged. Conventional battery equalization management systems often have some limitations when monitoring battery voltages, and it is impossible to accurately collect and analyze real-time battery actual voltage data. In particular, although the pressure difference of the battery can be kept within a specified range immediately after battery equalization, after a while, the pressure difference of the battery will increase, and equalization must be performed again, which has a great impact on the accuracy and stability of battery equalization.

Summary of the Invention

Problems to be Solved by the Invention

[0003] The technical problem to be solved by the present invention is to provide a battery equalization management method that can improve the accuracy and stability of battery equalization.

Means for Solving the Problems

[0004] To solve the above technical problems, the present invention adopts the following technical solutions: A battery equalization management method, comprising: step S10 of setting an operating time t1 and a stop time t2, where t1 / (t1 + t2) ≥ 80%; step S20 of performing a charge and discharge operation on the battery to eliminate the voltage difference within the battery during the operating time t1; step S30 of interrupting the charge and discharge operation and performing a reverse charge and discharge operation on the battery for a predetermined time using a small current to quickly stabilize the battery voltage during the stop time t2; step S40 of collecting the battery voltage after the battery voltage is stabilized to obtain accurate battery voltage data; and step S50 of determining whether battery equalization is completed based on the collected battery voltage data. If so, ending the current battery equalization operation; otherwise, returning to the execution of steps S20 - S40.

[0005] Preferably, the current value I of the small current is I = (y2 - y1)*(x - x1) / (x2 - x1) + y1, with the unit being milliamperes. Here, y1 and y2 are constants, x represents the rated voltage of the battery, x1 represents the lower limit value of the operating voltage range of the battery, and x2 represents the upper limit value of the operating voltage range of the battery.

[0006] Preferably, the battery is a lithium iron phosphate battery, the value of y1 is 100, the value of y2 is 200, the value of x is 3.7V, the value of x1 is 3.2V, and the value of x2 is 4.2V.

[0007] Preferably, the operating time t1 is set to 15 seconds and the stop time t2 is set to 2 seconds.

[0008] Preferably, the predetermined time is 100 - 500 ms.

[0009] Preferably, the predetermined time is 150 ms.

Advantages of the Invention

[0010] The beneficial technical effects of the present invention are as follows. The above battery equalization management method performs periodic charge and discharge operations on the battery, and after the charge and discharge operations stop, performs reverse charge and discharge operations on the battery using a small current to quickly stabilize the battery voltage. After the battery voltage stabilizes, voltage collection is performed on the battery, thereby obtaining accurate battery voltage data, and further performing determination and adjustment control of battery equalization based on the accurate battery voltage data, so as to improve the accuracy and stability of battery equalization.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying out the Invention

[0012] For those skilled in the art to more clearly understand the object, technical solution and advantages of the present invention, the present invention will be further described below with reference to the drawings and embodiments.

[0013] As shown in FIG. 1, in an embodiment of the present invention, the battery equalization management method includes steps S10 to S50.

[0014] In S10, an operating time t1 and a stop time t2 are set, and t1 / (t1 + t2) ≥ 80%.

[0015] In this embodiment, the operating time t1 is set to 15 seconds, and the stop time t2 is set to 2 seconds. Of course, in other embodiments, the operating time t1 may be set to 12 seconds, 16 seconds or other values, and the stop time t2 may be set to 3 seconds, 4 seconds or other values, as long as t1 / (t1 + t2) ≥ 80% is ensured.

[0016] In S20, within the operating time t1, a charge-discharge operation is performed on the battery to eliminate the voltage difference within the battery.

[0017] The charge-discharge operation includes a charging operation or a discharging operation. In this step, either a charging operation or a discharging operation may be alternatively performed on the battery.

[0018] When a charging operation is performed on the battery, as shown in FIG. 2, charging starts at time T0. When there is a charging current, the battery voltage immediately rises and then gradually rises with time. When a discharging operation is performed on the battery, as shown in FIG. 4, discharging starts at time T0. When there is a discharging current, the battery voltage immediately drops and then gradually drops with time.

[0019] In S30, within the stop time t2, the charge-discharge operation is interrupted, and a reverse charge-discharge operation is performed on the battery using a small current for a predetermined time to quickly stabilize the battery voltage.

[0020] In this embodiment, the set time is set to 150 ms. Of course, in other embodiments, the predetermined time may be set to 100 ms, 200 ms, 300 ms, 400 ms, 500 ms, or other values.

[0021] The current value of the small current is calculated by adopting I = (y2 - y1)*(x - x1) / (x2 - x1)+y1, and the unit is milliampere. Here, y1 and y2 are constants, x represents the rated voltage of the battery, x1 represents the lower limit value of the operating voltage range of the battery, and x2 represents the upper limit value of the operating voltage range of the battery. The constants y1 and y2 can be obtained through a plurality of experiments, and x, x1, and x2 are related to the battery. In this embodiment, the battery adopts a lithium iron phosphate battery, the value of y1 is 100, the value of y2 is 200, the value of x is 3.7V, the value of x1 is 3.2V, and the value of x2 is 4.2V. Therefore, the current value I of the small current = (200 - 100)*(3.7 - 3.2) / (4.2 - 3.2)+100 = 150 (milliampere).

[0022] When a charging operation is performed on the battery within the operation time t1, a reverse charge and discharge operation is performed on the battery, that is, a discharge operation is performed on the battery. As shown by the curve L1 in FIG. 3, the charging ends at time T0, a small current of 150 ma is applied at time T0 to discharge the battery, and the discharge is performed for approximately 150 ms, and the battery voltage stabilizes at time T1. Referring again to the curve L0 in FIG. 3, the charging ends at time T0, the battery voltage rises, and it stabilizes over a long period up to time T2. As can be seen by comparing the curve L1 and the curve L0 in FIG. 3, by applying a small current of 150 ma to perform a discharge operation on the battery at the end of charging, the time from the end of discharge until the battery voltage stabilizes can be significantly shortened.

[0023] When a discharge operation is performed on the battery within the operation time t1, a reverse charge and discharge operation is performed on the battery, that is, a charging operation is performed on the battery. As shown by the curve L1 in FIG. 5, the discharge ends at time T0, a small current of 150 ma is applied at time T0 to charge the battery, and the charging is performed for approximately 150 ms, and the battery voltage stabilizes at time T1. Referring again to the curve L0 in FIG. 5, the discharge ends at time T0, the battery voltage rises, and it stabilizes over a long period up to time T2. As can be seen by comparing the curve L1 and the curve L0 in FIG. 5, by applying a small current of 150 ma to perform a charging operation on the battery at the end of discharge, the time from the end of discharge until the battery voltage stabilizes can be significantly shortened.

[0024] In S40, after the battery voltage stabilizes, voltage collection is performed on the battery to obtain accurate battery voltage data.

[0025] In step S50, it is determined whether battery equalization is completed based on the collected battery voltage data. If so, the current battery equalization operation is terminated. If not, the process returns to the execution of steps S20 - S40.

[0026] The battery equalization management method of the present invention performs periodic charge and discharge operations on the battery. After the charge and discharge operations stop, a reverse charge and discharge operation is performed on the battery using a small current to quickly stabilize the battery voltage. After the battery voltage stabilizes, voltage collection is performed on the battery to obtain accurate battery voltage data. Furthermore, by performing battery equalization determination and adjustment control based on the accurate battery voltage data, the accuracy and stability of battery equalization are improved.

[0027] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Those skilled in the art can make various changes and improvements based on the above embodiments, and any equivalent changes or modifications made within the scope of the claims should be included within the protection scope of the present invention.

[0028] (Appendix) (Appendix 1) Step S10 of setting the operating time t1 and the stop time t2, where t1 / (t1 + t2) ≥ 80%, and Step S20 of performing a charge and discharge operation on the battery to eliminate the voltage difference within the battery during the operating time t1, and Step S30 of interrupting the charge and discharge operation and performing a reverse charge and discharge operation on the battery using a small current for a predetermined time to quickly stabilize the battery voltage during the stop time t2, and Step S40 of performing voltage collection on the battery to obtain accurate battery voltage data after the battery voltage stabilizes, and Determine whether battery equalization is completed based on the collected battery voltage data. If so, end the current battery equalization operation. Otherwise, return to step S50 to execute steps S20 - S40. A battery equalization management method characterized by this.

[0029] (Appendix 2) The current value I of the small current is I=(y2 - y1)*(x - x1) / (x2 - x1)+y1, and the unit is milliampere. Here, y1 and y2 are constants, x represents the rated voltage of the battery, x1 represents the lower limit value of the operating voltage range of the battery, and x2 represents the upper limit value of the operating voltage range of the battery. The battery equalization management method according to Appendix 1, characterized by this.

[0030] (Appendix 3) The battery is a lithium iron phosphate battery, the value of y1 is 100, the value of y2 is 200, the value of x is 3.7V, the value of x1 is 3.2V, and the value of x2 is 4.2V. The battery equalization management method according to Appendix 2, characterized by this.

[0031] (Appendix 4) Set the operating time t1 to 15 seconds and the stop time t2 to 2 seconds. The battery equalization management method according to Appendix 1, characterized by this.

[0032] (Appendix 5) The predetermined time is 100 - 500ms. The battery equalization management method according to any one of Appendices 1 - 4, characterized by this.

[0033] (Appendix 6) The predetermined time is 150ms. The battery equalization management method according to Appendix 5, characterized by this.

Claims

1. Operating time t １ and stop time t ２ Set t １ / (t １ +t ２ ) ≧80%; and Operating time t １ Step S20 of performing a charge / discharge operation on the battery so as to eliminate the voltage difference in the battery; Stop time t ２ Step S30: interrupting the charging / discharging operation and charging / discharging the battery in the reverse direction for a predetermined period of time using a small current so as to quickly stabilize the battery voltage; Step S40: after the battery voltage has stabilized, voltage collection is performed on the battery to obtain accurate battery voltage data; and step S50 of determining whether or not the battery equalization is completed based on the collected battery voltage data, and if so, terminating the current battery equalization operation, and if not, returning to execution of steps S20 to S40.

2. The current value of the small current I=(y ２ -y １ ) * (x-x １ ) / (x ２ -x １ ) + y １ and the units are milliamperes, where y １ , y ２ is a constant, x represents the rated voltage of the battery, and x １ represents the lower limit of the operating voltage range of the battery, and x ２ 2. The method of claim 1, wherein V represents an upper limit of an operating voltage range of the batteries.

3. The battery is a lithium phosphate battery, １ The value of y is 100, ２ The value of is 200, the value of x is 3.7 V, and １ The value of x is 3.2V. ２ 3. The method of claim 2, wherein the value of is 4.2V.

4. The operating time t １ is set to 15 seconds, and the stop time t ２ 2. The method of claim 1, wherein the equalization time is set to 2 seconds.

5. 5. The battery equalization management method according to claim 1, wherein the predetermined time is 100 to 500 ms.

6. 6. The method of claim 5, wherein the predetermined time is 150 ms.

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