Estimating condition of battery, related system and vehicle

Patent metadata

Field	Value
Publication number	US-11385295-B2
Application number	US-202016984680-A
Country	US
Kind code	B2
Filing date	Aug 4, 2020
Priority date	Jan 31, 2013
Publication date	Jul 12, 2022
Grant date	Jul 12, 2022

Abstract

An apparatus for estimating a condition of a battery includes a mode identifying unit configured to identify a usage mode of the battery during a period of time and its corresponding attenuation curve, according to recorded data on battery usage, stored usage modes of the battery and attenuation curves corresponding to the various usage modes, the attenuation curve representing a change of a fully charged capacity of the battery with battery usage; and a condition estimating unit configured to calculate battery degradation according to the recorded data, the identified usage mode and its corresponding attenuation curve, the degradation representing a quantity of the fully charged capacity of the battery that is reduced over the battery usage. The condition of the battery is estimated so as to rationally judge the residual value of the battery in operation.

First claim

The invention claimed is:

1. A method comprising:
identifying a first usage mode of a battery during a first period of time, the first usage mode being based on previously stored usage modes of the battery;
identifying a first corresponding attenuation curve of the battery based on recorded data of battery usage during the first period of time, previously stored usage modes of the battery, and attenuation curves corresponding to the previously stored usage modes, wherein each attenuation curve represents a change of a charged capacity of the battery over battery usage;
identifying a second usage mode of the battery during a second period of time, the second usage mode being different from the first usage mode;
identifying a second corresponding attenuation curve of the battery based on recorded data of battery usage during the second period of time, previously stored usage modes of the battery, and attenuation curves corresponding to the previously stored usage modes;
calculating a degradation of the battery during a combined period of time that includes the first period of time and the second period of time according to the recorded data, the identified first and second usage mode, and a slope of the first corresponding attenuation curve and the second corresponding attenuation curve, the degradation representing a quantity of the charged capacity of the battery that was reduced over the battery usage during the combined period of time; and
billing an adjusted amount to a user of the battery, the adjusted amount being determined based at least in part on a depreciation expense of the battery, the depreciation expense being based on the degradation of the battery, the adjusted amount rationally representing a residual value of the battery for rational billing.

2. The method of claim 1 , wherein the data on battery usage comprises: a start time and end time of battery usage, initial voltage and final voltage of battery usage, charge current, charge level, temperature, discharge current, idle time, and depth of discharge representing quantity of electricity energy of the battery before idle.

3. The method of claim 2 , wherein when the identified first usage mode is a charging mode, the battery degradation is calculated according to charge level L, charging capacity δ e , temperature T, initial charging voltage U a and final charging voltage U b as follows:
calculate the charging capacity δ e during the period of time according to a start time of charging t a , an end time of charging t b and a charge current I c of the first period of time;
search previously stored charging modes of the battery and attenuation curves corresponding to the charging modes for a set {M a } of all charging modes matching charge level L, initial charging voltage U a and temperature T, and a set {M b } of all charging modes matching charge level L, final charging voltage U b and temperature T;
search the set {M b } and the set {M a } respectively for a mode m b and a mode m a such that a difference between the charging capacity of the mode m b and the charging capacity of the mode m a is equal to δe;
according to attenuation curves f a and f b corresponding to the modes m a and m b , calculate slopes s a and s b of the attenuation curves f a and f b at a point c=c a respectively, wherein c a represents a charged capacity of the battery at the start time of charging t a , and s a and s b respectively represent degradation caused by charging the battery from a standard cut-off voltage to the initial charging voltage U a and the final charging voltage U b under the condition of the charge current I c and temperature T; and
calculate battery degradation s=s b −s a during the first period of time, and obtaining a charging capacity c b =c a +s of the battery at a time t b .

4. The method of claim 3 , wherein, estimating the condition of the battery further comprises:
calculating a rate of depreciation

D
r

=

C
a

-

C
b

C
0

-

C
e

caused by using the battery once, where c 0 is a factory capacity of the battery and c e is a scrap capacity of the battery.

5. The method of claim 3 , wherein, estimating the condition of the battery further comprises:
calculating a remaining quantity of electricity energy of the battery according to the previously stored usage modes of battery and efficiencies corresponding to the usage modes, wherein the remaining quantity of electricity energy of the battery is obtained by accumulating changes of the remaining quantity of electricity energy caused by battery usage on the basis of a factory electricity energy e 0 of the battery.

6. The method of claim 5 , wherein, when the identified first usage mode is a charging mode, the remaining quantity of electricity energy is calculated as follows:
calculating the charging capacity δ e during the first period of time according to start time of charging t a , end time of charging t b and charge current I c of the first period of time;
searching the previously stored usage modes of battery and efficiencies corresponding to the usage modes for the charging mode and a corresponding charging efficiency α according to the data on battery usage recorded during the first period of time; and
calculating the remaining quantity of electricity energy e b =e a +α·c a /c 0 ·δe of the battery at the time t b , where c 0 is a factory capacity of the battery and e a is the remaining quantity of electricity energy of the battery at a time t a .

7. The method of claim 2 , wherein when the first identified usage mode is a discharging mode, the battery degradation is calculated according to discharge current I d , temperature T, initial discharging voltage U a and final discharging voltage U b as follows:
searching previously stored discharging modes of the battery and attenuation curves corresponding to the discharging modes for a discharging mode m a matching discharge current I d , initial discharging voltage U a and temperature T, and a discharging mode m b matching discharge current I d , final discharging voltage U b and temperature T;
according to attenuation curves f a and f b corresponding to the modes m a and m b , calculating slopes s a and s b of the attenuation curves f a and f b at a point c=c a respectively, wherein c a represents a charged capacity of the battery at a time t a , and s a and s b respectively represent degradation caused by discharging the battery from the initial discharging voltage U a and the final discharging voltage U b to a standard cut-off voltage under the condition of the discharge current I d and temperature T; and
calculating battery degradation s=s b −s a during the period of time, and obtaining a charged capacity c b =c a +s of the battery at a time t b .

8. The method of claim 2 , wherein, when the identified first usage mode is idle mode, the battery degradation is calculated according to depth of discharge d and temperature T as follows:
searching stored idle modes of the battery and attenuation curves corresponding to the idle modes for a discharging mode m matching the depth of disc

Assignees

• Utopus Insights Inc

Inventors

• Dong Jin
• Gammons Carlton
• Shao Jin Yan
• Tian Qi Ming
• Xie Ming
• Yin Wen Jun
• Yu hong guang
• Zhao Li Li

Classifications

• G01R31/392 Primary

  Determining battery ageing or deterioration, e.g. state of health · CPC title

• G01R31/367

  Software therefor, e.g. for battery testing using modelling or look-up tables · CPC title