Method and apparatus for battery operation and maintenance, and electronic device therewith
View Patent ↗The invention discloses method and apparatus for operation and maintenance of a battery and an electronic device. The method includes: performing a charging/discharging process on a to-be-analyzed battery cluster, and determining key battery parameters (KBP) of a plurality of cells in the battery cluster; determining whether the battery cluster is abnormal depending on whether the KBPs of the cells in the battery cluster exceed a normal range; and performing operation and maintenance on the battery cluster in a case that the battery cluster is abnormal. The internal resistance, the capacity parameter, and the self-discharge parameter of the cells are used as the KBPs of the cells. Based on the KBPs, whether the cells are abnormal can be determined more accurately, and the cause of the abnormality can be determined. Accordingly, more accurate operation and maintenance can be subsequently realized for the battery cluster when required.
1 . A method for operation and maintenance of a battery, comprising:
performing a charging/discharging process on a to-be-analyzed battery cluster, and determining key battery parameters (KBP) of a plurality of cells in the battery cluster, wherein the KBPs comprise an internal resistance, capacity parameters, and a self-discharge parameter;
determining whether the battery cluster is abnormal depending on whether the KBPs of the cells in the battery cluster exceed a normal range; and
performing operation and maintenance on the battery cluster in a case that the battery cluster is abnormal,
wherein said performing the charging/discharging process on the to-be-analyzed battery cluster, and said determining the KBPs of the plurality of cells in the battery cluster comprises:
performing a full charging/discharging process on the to-be-analyzed battery cluster, and determining differential capacities versus voltage of the plurality of cells in the battery cluster at different times, wherein a constant current exists in at least part of a time period of the full charging/discharging process; and
determining first times and first states of charge (SOC) when the differential capacities versus voltage of the cells reach a first peak and second times and second SOCs when the differential capacities versus voltage of the cells reach a second peak, and determining the capacity parameters of the cells according to the first times, the first SOCs, the second times, and the second SOCs, wherein the second SOCs are greater than the first SOCs.
2 . The method according to claim 1 , wherein said determining whether the battery cluster is abnormal comprises:
presetting a corresponding abnormality threshold for each of the KBPs; and
determining that the cells in the battery cluster are abnormal in a case that the KBPs of the cells exceed the abnormality threshold.
3 . The method according to claim 2 , wherein at least one of the abnormality thresholds is a threshold determined according to a KBP in historical operation data or a safety parameter provided by a manufacturer; or
the abnormality threshold r th is: r th =(r 1 +r 0 )/2+σ 2 ln λ/(r 1 −r 0 ), wherein r 1 is a value corresponding to a determination that the KBP is abnormal, r 0 and σ respectively represent an average value and a mean square difference of a data stream transmitted when the KBPs are normal, and λ is a preset coefficient related to a confidence level.
4 . The method according to claim 1 , wherein said determining whether the battery cluster is abnormal comprises:
determining whether the KBPs of the plurality of cells exceed a normal distribution range according to a distribution of the KBPs of the cells; and
determining that the cells are abnormal in a case that the KBPs of the cells exceed the normal distribution range.
5 . The method according to claim 1 , wherein said performing operation and maintenance on the battery cluster comprises:
dynamically adjusting a charging/discharging control parameter of the battery cluster in a case that the battery cluster is in a sub-healthy state;
equalizing the battery cluster if a capacity allowed to be increased that is determined based on the capacity parameters is greater than a preset capacity in a case that the battery cluster is in the sub-healthy state; and
enabling/disabling the battery cluster in a case that the battery cluster is in a faulty state.
6 . The method according to claim 1 , wherein the self-discharge parameter comprises a full charge time difference, and the full charge time difference of a cell k in the battery cluster is a difference between a full charge time of the cell k and a full charge time of a reference cell in the battery cluster.
7 . The method according to claim 6 , wherein said performing operation and maintenance on the battery cluster comprises:
charging the cell k alone to an ending voltage after charging of the battery cluster ends in a case that the full charge time difference of the cell k is abnormal and the internal resistance is normal; and
discharging the cell k alone to an ending voltage after discharging of the battery cluster ends in a case that the internal resistance of the cell k is abnormal and the full charge time difference is normal.
8 . The method according to claim 1 , wherein the capacity parameters of a cell k in the battery cluster comprises a capacity C k,chrend by which the cell k is to be further charged when a charging ending moment of the battery cluster is reached and a capacity C k,disend by which the cell k is to be further discharged when a discharging ending moment of the battery cluster is reached.
9 . The method according to claim 8 , wherein said performing operation and maintenance on the battery cluster comprises:
determining, according to a capacity by which each of the cells is to be further charged at a charging ending moment of the battery cluster, the earliest fully charged cell j in the battery cluster and the earliest fully charged cell j′ other than the cell j, wherein
if the cell j is replaced, an effective charge capacity of the battery cluster is increased by C j′,chrend ; and
if the cell j is discharged alone to an ending voltage after discharging of the battery cluster ends, the effective charge capacity of the battery cluster is increased by min [C j′,chrend , C j,disend ].
10 . The method according to claim 1 , wherein said performing operation and maintenance on the battery cluster comprises:
determining, according to a capacity by which each of the cells is to be further discharged at a discharging ending moment of the battery cluster, the earliest fully discharged cell i in the battery cluster and the earliest fully discharged cell i′ other than the cell i, wherein
if the cell i is replaced, an effective discharge capacity of the battery cluster is increased by C i′,disend , and
if the cell i is charged alone to an ending voltage after charging of the battery cluster ends, the effective discharge capacity of the battery cluster is increased by min [C i′,disend , C i,chrend ].
11 . The method according to claim 1 , wherein
in a case that the full charging/discharging process comprises a full charging process, in the full charging process, the constant current exists in at least a time period from a charging beginning time to a largest one of the second times of the plurality of cells, and the full charging process begins when the battery cluster reaches a discharging ending voltage and ends when the battery cluster reaches a charging ending voltage; and
in a case that the full charging/discharging process comprises a full discharging process, in the full discharging process, the constant current exists in at least a time period from a smallest one of the second times of the plurality of cells to a discharging ending time, and the full discharging process begins when the battery cluster reaches the charging ending voltage and ends when the battery cluster reaches the discharging ending voltage.
12 . The method according to claim 11 , wherein said determining the capacity parameters of the cells according to the first times, the first SOCs, the second times, and the second SOCs comprises:
determining, according to a first SOC k,I peak and a second SOC k,II peak of the cell k in the battery cluster, a difference ΔSOC k between the SOCs of the cell k when reaching the first peak and the second peak, wherein ΔSOC k =SOC k,II peak −SOC k,I peak ; and
determining a difference ΔQ k between capacities of the cell k when reaching the first peak and the second peak, and determining a maximum capacity Q kmax of the cell k, wherein Q kmax =100%×ΔQ k /ΔSOC k .
13 . The method according to claim 12 , wherein said determining the capacity parameters of the cells according to the first times, the first SOCs, the second times, and the second SOCs further comprises:
determining a charging ending SOC k,end of the cell k at a charging ending moment of the battery cluster according to a target time and a target SOC when the cell k reaches a target peak and the maximum capacity Q kmax of the cell k, wherein the target peak is the first peak or the second peak, and the target time is the corresponding first time or second time; and
determining, based on the charging ending SOC k,end of the cell k, the capacity C k,chrend by which the cell k is to be further charged when the charging ending moment of the battery cluster is reached and the capacity C k,disend by which the cell k is to be further discharged when a discharging ending moment of the battery cluster is reached, wherein the capacity C k,chrend by which the cell is to be further charged at the charging ending moment and the capacity C k,disend by which the cell is to be further discharged at the discharging ending moment satisfy:
C
k
,
chrend
=
(
1
-
S
O
C
k
,
e
n
d
)
×
Q
kmax
;
C
k
,
disend
=
SO
C
k
,
e
n
d
×
Q
kmax
-
∫
t
k
,
begin
t
k
,
end
I
dt
,
where t k,begin represents a beginning time of the full charging/discharging process of the cell k, t k,end represents an ending time of the full charging/discharging process of the cell k, and I represents a current value in the full charging/discharging process.
14 . The method according to claim 13 , wherein said determining the capacity parameters of the cells according to the first times, the first SOCs, the second times, and the second SOCs further comprises:
determining a charge capacity C k,charge of the cell k and a discharge capacity C k,discharge of the cell k, wherein the charge capacity C k,charge and the discharge capacity C k,discharge satisfy:
C
k
,
charge
=
∫
t
k
,
b
e
g
i
n
t
k
,
end
I
dt
+
(
1
-
S
O
C
k
,
e
n
d
)
×
Q
kmax
;
C
k
,
discharge
=
S
O
C
k
,
end
×
Q
kmax
.
15 . The method according to claim 13 , wherein in a case that the full charging/discharging process comprises the full charging process, the charging ending SOC k,end of the cell k satisfies:
S
O
C
k
,
e
n
d
=
S
O
C
k
,
T
peak
+
∫
t
k
,
T
peak
t
k
,
chrend
I
dt
/
Q
kmax
;
in a case that the full charging/discharging process comprises the full discharging process, the charging ending SOC k,end of the cell k satisfies:
SO
C
k
,
e
n
d
=
S
O
C
k
,
T
peak
+
∫
t
k
,
disbegin
t
k
,
T
peak
I
dt
/
Q
kmax
,
where SOC k,T peak represents an SOC of the target peak, t k,T peak represents the target time of the target peak, t k,chrend represents a charging ending time of the cell k, and t k,disbegin represents a discharging beginning time of the cell k.
16 . An electronic device, comprising a bus, a transceiver, a memory, a processor, and a computer program stored in the memory and runnable on the processor, wherein the transceiver, the memory, and the processor are connected through the bus, and when the computer program is executed by the processor, the steps in the method for battery operation and maintenance according to claim 1 are implemented.
17 . A non-transitory tangible computer-readable storage medium, storing a computer program therein, wherein when the computer program is executed by a processor, the steps in the method for battery operation and maintenance according to claim 1 are implemented.