Method, apparatus, electronic device and storage medium for detecting water content in battery

1. A method for determining water content in a battery, comprising:

obtaining a capacitance detection value of the battery; and

determining a first water content value of the battery according to the capacitance detection value and a capacitance-water content relationship model;

wherein the capacitance-water content relationship model is constructed according to corresponding relationships between sample batteries with different water content values and their respective sample capacitance values; and

wherein obtaining the capacitance detection value of the battery comprises:

after determining that the battery reaches a detection position, connecting a detection probe to positive and negative electrodes of the battery;

applying an alternating current with a constant voltage to the battery through the detection probe, and measuring a capacitive reactance value of the battery; and

obtaining the capacitance detection value of the battery according to the capacitive reactance value of the battery.

2. The method according to claim 1 , further comprising:

acquiring a battery temperature of the battery; and

correcting the capacitance detection value according to the battery temperature and a temperature-capacitance relationship model, to obtain a corrected capacitance value;

wherein determining the first water content value of the battery according to the capacitance detection value and the capacitance-water content relationship model comprises:

determining the first water content value of the battery according to the corrected capacitance value and the capacitance-water content relationship model.

3. The method according to claim 2 , wherein acquiring the battery temperature of the battery comprises:

obtaining an oven-discharging duration of the battery; and

determining the battery temperature of the battery according to the oven-discharging duration and a duration-temperature relationship function.

4. The method according to claim 1 , further comprising:

acquiring production parameters of the battery; and

correcting parameters in the capacitance-water content relationship model according to the production parameters, to obtain a corrected capacitance-water content relationship model;

wherein determining the first water content value of the battery according to the capacitance detection value and the capacitance-water content relationship model comprises:

determining the first water content value of the battery according to the capacitance detection value and the corrected capacitance-water content relationship model.

5. The method according to claim 1 , further comprising:

acquiring a battery temperature and production parameters of the battery;

correcting the capacitance detection value according to the battery temperature and a temperature-capacitance relationship model, to obtain a corrected capacitance value; and

correcting parameters in the capacitance-water content relationship model according to the production parameters, to obtain a corrected capacitance-water content relationship model;

wherein determining the first water content value of the battery according to the capacitance detection value and the capacitance-water content relationship model comprises:

determining the first water content value of the battery according to the corrected capacitance value and the corrected capacitance-water content relationship model.

6. The method according to claim 1 , further comprising:

acquiring a battery temperature of the battery;

wherein determining the first water content value of the battery according to the capacitance detection value and the capacitance-water content relationship model comprises:

acquiring a capacitance-water content relationship model corresponding to the battery temperature from a model library according to the battery temperature, wherein the model library comprises capacitance-water content relationship models corresponding respectively to a plurality of battery temperatures; and

determining the first water content value of the battery according to the capacitance detection value and the capacitance-water content relationship model corresponding to the battery temperature.

7. The method according to claim 1 , further comprising:

obtaining the sample batteries with different water content values;

measuring the sample capacitance values and second water content values of the sample batteries; and

constructing the capacitance-water content relationship model according to the sample capacitance values and the second water content values.

8. The method according to claim 7 , wherein

the sample batteries with different water content values are obtained by pre-baking sample batteries and placing the sample batteries in environments with different humidity for a pre-set duration; or

the sample batteries with different water content values are obtained by pre-baking the sample batteries in a same baking temperature for different baking durations.

9. An apparatus for determining water content battery, comprising:

a battery measurement unit; and

a computing device in communication with the battery measurement unit;

wherein the computing device comprises a processor and a memory storing program instructions executable by the processor;

wherein the program instructions, when executed by the processor, cause apparatus to:

obtain a capacitance detection value of the battery; and

determine a first water content value of the battery according to the capacitance detection value and a capacitance-water content relationship model;

wherein the capacitance-water content relationship model is constructed according to corresponding relationships between sample batteries with different water content values and their respective sample capacitance values; and

wherein in obtaining the capacitance detection value of the battery, the battery measurement unit is configured to:

after determining that the battery reaches a detection position, connect a detection probe to positive and negative electrodes of the battery;

apply an alternating current with a constant voltage to the battery through the detection probe. and measuring a capacitive reactance value of the battery; and

obtain the capacitance detection value of the battery according to the capacitive reactance value of the battery.

10. The apparatus according to claim 9 , wherein the program instructions, when executed by the processor, further cause the apparatus to:

acquire a battery temperature of the battery; and

correct the capacitance detection value according to the battery temperature and a temperature-capacitance relationship model, to obtain a corrected capacitance value;

wherein in determining the first water content value of the battery according to the capacitance detection value and the capacitance-water content relationship model, the apparatus is configured to:

determine the first water content value of the battery according to the corrected capacitance value and the capacitance-water content relationship model.

11. The apparatus according to claim 10 , wherein in acquiring the battery temperature of the battery, the apparatus is configure to:

obtain an oven-discharging duration of the battery; and

determine the battery temperature of the battery according to the oven-discharging duration and a duration-temperature relationship function.

12. The apparatus according to claim 9 , wherein the program instructions, when executed by the processor, further cause the apparatus to:

acquire production parameters of the battery; and

correct parameters in the capacitance-water content relationship model according to the production parameters, to obtain a corrected capacitance-water content relationship model;

wherein in determining the first water content value of the battery according to the capacitance detection value and the capacitance-water content relationship model, the apparatus is configured to:

determine the first water content value of the battery according to the capacitance detection value and the corrected capacitance-water content relationship model.

13. The apparatus according to claim 9 , wherein the program instructions, when executed by the processor, further cause the apparatus to:

acquire a battery temperature and production parameters of the battery;

correct the capacitance detection value according to the battery temperature and a temperature-capacitance relationship model, to obtain a corrected capacitance value; and

correct parameters in the capacitance-water content relationship model according to the production parameters, to obtain a corrected capacitance-water content relationship model;

wherein in determining the first water content value of the battery according to the capacitance detection value and the capacitance-water content relationship model, the apparatus is configured to:

determine the first water content value of the battery according to the corrected capacitance value and the corrected capacitance-water content relationship model.

14. The apparatus according to claim 9 , wherein the program instructions, when executed by the processor, further cause the apparatus to:

acquire a battery temperature of the battery;

wherein in determining the first water content value of the battery according to the capacitance detection value and the capacitance-water content relationship model, the apparatus is configured to:

acquire a capacitance-water content relationship model corresponding to the battery temperature from a model library according to the battery temperature, wherein the model library comprises capacitance-water content relationship models corresponding respectively to a plurality of battery temperatures; and

determine the first water content value of the battery according to the capacitance detection value and the capacitance-water content relationship model. corresponding to the battery temperature.

15. The apparatus according to claim 9 , wherein the program instructions, when executed by the processor, further cause the apparatus to:

obtain the sample batteries with different water content values;

measure the sample capacitance values and second water content values of the sample batteries, and

construct the capacitance-water content relationship model according to the sample capacitance values and the second water content values.

16. The apparatus according to claim 15 , wherein

the sample batteries with different water content values are obtained by pre-baking sample batteries and placing the sample batteries in environments with different humidity for a pre-set duration; or

the sample batteries with different water content values are obtained by pre-baking the sample batteries in a same baking temperature for different baking durations.

17. A non-transitory computer-readable storage medium storing computer instructions which, when executed by a computer processor, cause a device having the processor and a battery measurement unit to execute a method for determining water content in a battery, wherein the method comprises:

obtaining a capacitance detection value of the battery; and

determining a first water content value of the battery according to the capacitance detection value and a capacitance-water content relationship model;

wherein the capacitance-water content relationship model is constructed according to corresponding relationships between sample batteries with different water content values and their respective sample capacitance values; and

wherein obtaining the capacitance detection value of the battery comprises;

after determining that the battery reaches a detection position, connecting a detection probe to positive and negative electrodes of the battery;

applying an alternating current with a constant voltage to the battery through the detection probe, and measuring a capacitive reactance value of the battery; and

obtaining the capacitance detection value of the batten according to the capacitive reactance value of the battery.