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US5625272A Expired / Lapsed US ⏱️ 0.0 years remaining

Battery charge/discharge control method for electric vehicle

Assignee: Subaru Corp
•
Filing: 1995-11-02
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Granted: 1997-04-29
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Expires: 2015-11-02
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Abstract

Abstract A method of controlling charge or discharge of a battery for an electric vehicle comprises the steps of, dividing a battery into a plurality of blocks each composed of a plurality of cells for constituting the battery in all, detecting terminal voltages (V n ) of the divided blocks, respectively to obtain a difference (V max -V min ) in voltage between a maximum value and a minimum value from among the detected terminal voltages of the respective divided blocks, and controlling the charge or discharge of the battery on the basis of the obtained difference in voltage between the maximum and minimum values of the terminal voltages of the divided blocks. In practice, when the voltage difference (V max -V min ) between the maximum value and the minimum value is equal to or higher than a specified value (V Kc , V Kd ), the battery is stopped from being further charged or discharged; the charge or discharge current is limited; or the charge or discharge current is decreased stepwise at each control start period, to prevent the low-performance cells from being overcharged or over-discharged, that is, for prevention of the partial cells from being deteriorated due to a performance difference between the respective cells.

Inventors

  • 👤 Tsutomu Takahashi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 10:40
CPC Classifications
H; H01; H01M; H01M10/00; H01M10/42; H01M10/44; H01M10/441; B; B60; B60L; B60L53/00; B60L58/00; B60L58/10; H02; H02J; H02J7/00; H02J7/50; H02J7/52; H02J7/54; H02J7/90; H02J7/92; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y02T; Y02T10/00; Y02T10/60; Y02T10/70; Y02T10/7072; Y02T90/00; Y02T90/10; Y02T90/14

Claims Analysis

Total Claims: 9
Claim 1
Independent Claim 134 words
A method of controlling charge or discharge of a battery for an electric vehicle, said method comprising the steps of: dividing the battery into a plurality of blocks each having a plurality of cells for constituting the battery in all; detecting terminal voltages (V n ) of the divided blocks, respectively, to obtain a difference (V max -V min ) in voltage between a maximum value (V max ) and a minimum value (V min ) from among the detected terminal voltages of the respective divided blocks; and controlling the charge or discharge of the battery (4) on the basis of the obtained difference (V max -V min ) in voltage between the maximum and minimum values (V max , V min ) of the terminal voltages (V n ) of the divided blocks.
Claim 2
Independent Claim 134 words
A method of controlling charge or discharge of a battery for an electric vehicle, said method comprising the steps of: dividing the battery into a plurality of blocks each having a plurality of cells for constituting the battery in all; detecting terminal voltages (V n ) of the divided blocks, respectively, to obtain a difference (V max -V min ) in voltage between a maximum value (V max ) and a minimum value (V min ) from among the detected terminal voltages of the respective divided blocks; and controlling the charge or discharge of the battery (4) on the basis of the obtained difference (V max -V min ) in voltage between the maximum and minimum values (V max , V min ) of the terminal voltages (V n ) of the divided blocks.
Claim 3
Dependent Claim 131 words
The method of controlling charge or discharge of the battery according to claim 1, wherein said controlling step includes the steps of: setting a specified charge or discharge value (V Kc , V Kd ); comparing the obtained difference (V max -V min ) in voltage between the maximum and minimum values (V max , V min ) of the terminal voltages (V n ) with the set charge or discharge specified value (V Kc , V Kd ); and stopping the battery from being further charged or discharged, when the obtained difference (V max -V min ) in voltage between the maximum and minimum values (V max , V min ) is equal to or larger than the set specified charge or discharge value (V Kc , V Kd ).
Claim 4
Dependent Claim 60 words
The method of controlling charge or discharge of the battery according to claim 1, wherein said controlling step includes the step of: limiting charge or discharge current supplied to the battery, according to the difference (V max -V min ) between the maximum and minimum voltages (V max , V min ) of the respective blocks of the battery (4).
Claim 5
Dependent Claim 111 words
The method of controlling charge or discharge of the battery according to claim 3, wherein said limiting step includes the step of: determining a charge or discharge limit value (ΔI c ,ΔI d ) of the battery, with reference to a map representative of relationship between the charge or discharge current limit value (ΔI c ,ΔI d ) and the obtained difference (V max -V min ) in voltage between the maximum and minimum values (V max , V min ); and decreasing the charge or discharge current so that the current is equal to or smaller than the determined charge or discharge current limit value (ΔI c ,ΔI d ).
Claim 6
Dependent Claim 72 words
The method of controlling charge or discharge of the battery according to claim 1, further comprising the steps of: detecting temperatures (T n ) of the divided blocks; and correcting the detected terminal voltages (V n ) of the divided blocks on the basis of temperature coefficients (K T ) determined according to detected temperatures of the divided blocks to obtain temperature corrected terminal voltages (V Tn =V n ·K T ).
Claim 7
Dependent Claim 132 words
The method of controlling charge or discharge of the battery according to claim 5, wherein said controlling step includes the steps of: setting a specified charge or discharge value (V KTc , V KTd ); comparing the obtained difference (V Tmax -V Tmin ) in voltage between the maximum and minimum values (V Tmax , V Tmin ) of the terminal voltages (V Tn ) with the set charge or discharge specified value (V KTc , V KTd ); and stopping the battery from being further charged or discharged, when the obtained difference (V KTc , V KTd ) in voltage between the maximum and minimum values (V Tmax , V Tmin ) is equal to or larger than the set specified charge or discharge value (V KTc , V KTd ).
Claim 8
Dependent Claim 59 words
The method of controlling charge or discharge of the battery according to claim 5, wherein said controlling step includes the step of: limiting charge or discharge current supplied to the battery, according to the difference (V Tmax -V Tmin ) between the maximum and minimum voltages (V Tmax , V Tmin ) of the respective blocks of the battery.
Claim 9
Dependent Claim 112 words
The method of controlling charge or discharge of the battery according to claim 7, wherein said limiting step includes the step of: determining a charge or discharge limit value (ΔI c ,ΔI d ) of the battery, with reference to a map representative of relationship between the charge or discharge current limit value (ΔI c , ΔI d ) and the obtained difference (V Tmax -V Tmin ) in voltage between the maximum and minimum values (V Tmax , V Tmin ); and decreasing the charge or discharge current so that the current is equal to or smaller than the determined charge or discharge current limit value (ΔI c ,ΔI d ).

References Cited (Backward Citations)

US3997830A Cited
US5387857A Cited
US5352968A Cited
US5469042A Cited
US5557189A Cited

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