Method and device for detecting charging abnormality, and storage medium

1. A method for detecting charging abnormality, wherein the method comprises:

obtaining n consecutive sampled voltages of a first cell from an end moment of an i th charging phase to an end moment of an (i+1) th charging phase in a k th charging process of a battery, wherein the first cell is any one cell in the battery, a first charge current in the i th charging phase is greater than a second charge current in the (i+1) th charging phase, i is greater than or equal to 1, k is greater than or equal to 2, and n is greater than 2, wherein the n consecutive sampled voltages comprise an m th sampled voltage at an m th sampling moment to an (m+n−1) th sampled voltage at an (m+n−1) th sampling moment,

wherein obtaining n consecutive sampled voltages of a first cell from an end moment of an i th charging phase to an end moment of an (i+1) th charging phase in a k th charging process comprises:

switching the first current to the second current directly if a current difference between the first current and the second current is greater than a current threshold, and obtaining the n sampled voltages from the m th sampling moment to the (m+n−1) th sampling moment after the first current is switched to the second current; switching, if the current difference is less than or equal to the current threshold, the first current to a third current, and then switching the third current to the second current, and obtaining the n sampled voltages from the m th sampling moment to the (m+n−1) th sampling moment after the third current is switched to the second current, wherein the third current is greater than the first current; and

determining a first sampling moment corresponding to a first minimum voltage in the n sampled voltages based on the n consecutive sampled voltages, comprising:

determining that the m th sampled voltage at the m th sampling moment is a minimum voltage;

updating the minimum voltage with the sampled voltage at the (m+j) th sampling moment if the sampled voltage at the (m+j) th sampling moment is less than the sampled voltage at the (m+j−1) th sampling moment;

determining, if the sampled voltage at the (m+j) th sampling moment is less than or equal to sampled voltages at an (m+j+1) th sampling moment to the (m+n−1) th sampling moment, that the (m+j) th sampling moment is the first sampling moment corresponding to the first minimum voltage, wherein j is greater than or equal to 1 and less than or equal to n−2, and m is greater than or equal to 1; and

determining abnormality of the k th charging process if the first minimum voltage is greater than a second minimum voltage, and determining abnormality of the k th charging process if the rate of change of the sampled voltages in a first period in the k th charging process is less than the rate of change of the sampled voltages in a second period in a L th charging process,

wherein

the second minimum voltage is a minimum voltage of the first cell from the end moment of the i th charging phase to the end moment of the (i+1) th charging phase in the L th charging process, a sampling moment of the second minimum voltage is a second sampling moment, and the L th charging process is any one of first (k−1) th charging processes; and,

the first period is a period after the first sampling moment, the second period is a period after the second sampling moment, and a length of the first period is equal to a length of the second period.

2. The method according to claim 1 , wherein the method further comprises:

updating a quantity of abnormal charging processes of the battery to obtain a cumulative quantity of abnormal charging processes; and

stopping charging the battery when the cumulative quantity of abnormal charging processes exceeds a preset quantity.

3. A device for detecting charging abnormality, wherein the device comprises means for performing the method according to claim 1 .

4. A battery, wherein the battery comprises the device for detecting charging abnormality according to claim 3 .

5. A charging device, configured to charge a battery, wherein the charging device comprises the device for detecting charging abnormality according to claim 3 .

6. A non-transitory computer-readable storage medium on which a computer program is stored, wherein, when executed by a processor, the computer program implements the method for detecting charging abnormality according to claim 1 .