Method for managing a battery according to its state of health

Patent metadata

Field	Value
Publication number	US-10680294-B2
Application number	US-201815951380-A
Country	US
Kind code	B2
Filing date	Apr 12, 2018
Priority date	Apr 13, 2017
Publication date	Jun 9, 2020
Grant date	Jun 9, 2020

Abstract

A method for managing a battery according to a state of health of the battery, comprising, prior to using the battery, predetermining a maximum depth of discharge profile according to the state of health of the battery, the profile being dependent on a technology of the battery, on a nominal energy level to be made available each time the battery is discharged, the nominal energy level being substantially constant over a service life of the battery. While using the battery, a maximum depth of discharge of the battery is adjusted at regular intervals, each time the state of health of the battery decreases by a percentage corresponding to an update interval p % that is equal to p/100, that is, for all state of health values (SOHn) that are equal to SOH0-n×p %, where n is an integer comprised between 0 and 20/p.

First claim

The invention claimed is:

1. A method for managing a battery according to a state of health of the battery, comprising:
prior to using the battery, a step of determining and setting a maximum depth of discharge profile according to the state of health of the battery, the maximum depth of discharge profile being a percentage maximum electrical discharge consumed in a single discharging phase of the battery with respect to the capacity of the battery at that discharge phase, and said maximum depth of discharge profile being dependent on a technology of the battery, on a nominal energy level to be made available each time the battery is discharged, the nominal energy level being substantially constant over a service life of the battery, that is, between a start of life state (SOH 0 ) associated with an initial maximum depth of discharge value (MDOD 0 ) and an end of life state (SOH 20 ) associated with a maximum depth of discharge limit threshold (MDOD 20 );
while using the battery, a step of adjusting the maximum depth of discharge of the battery according to the current state of health of the battery; and,
wherein the maximum depth of discharge of the battery is adjusted at regular intervals, each time the state of health of the battery decreases by a percentage corresponding to an update interval p % that is equal to p/100, that is, for all state of health values (SOH n ) that are equal to SOH 0 -n×p %, where n is an integer comprised between 0 and 20/p.

2. The method according to claim 1 , wherein the maximum depth of discharge (MDOD n ) of the battery is adjusted to the state of health according to the following relation:

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3. The method according to claim 1 , wherein the update interval p % is lower than or equal to 1%.

4. The method according to claim 1 , wherein the initial value (MDOD 0 ) and the maximum depth of discharge (MDOD) profile are determined in the predetermination step such that the depth of discharge of the battery is, over the service life of the battery, always or nearly always lower than a maximum value.

5. The method according to claim 1 , wherein the initial value (MDOD 0 ) and the maximum depth of discharge (MDOD) profile are determined according to the limit threshold value (MDOD 20 ).

6. The method according to claim 1 , in which a maximum charge setpoint is provided during the charging phases of the battery, the maximum charge setpoint varying upwards so as to maintain a substantially constant available energy level over the service life of the battery while limiting overcharge-related risks.

7. A method for managing a specific battery according to a state of health of the battery, comprising:
setting a maximum depth of discharge profile according to the state of health of the battery, the maximum depth of discharge profile being a percentage maximum electrical discharge consumed in a single discharging phase of the battery with respect to the capacity of the battery at that discharging phase, and said maximum depth of discharge, and the maximum depth of discharge profile being an upward profile, which is determined by:
the technology of the specific battery,
a substantially constant nominal energy level to be made available each time the specific battery is discharged, and
a limit threshold value of the maximum depth of discharge;

while using the battery, a step of adjusting a maximum depth of discharge of the battery according to the current state of health of the battery;
wherein the maximum depth of discharge of the battery is adjusted at regular intervals, each time the state of health of the battery decreases by a percentage corresponding to an update interval p % that is equal to p/100, that is, for all state of health values (SOH n ) that are equal to SOH 0 -n×p %, where n is an integer comprised between 0 and 20/p,
wherein, the maximum depth of discharge (MDOD n ) of the battery is adjusted to the state of health according to the following relation:

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Assignees

• Airbus Sas

Inventors

• Ferran Benoit
• Joubert Emmanuel
• Dinel Clément

Classifications

• H02J7/0063

  Electricity · mapped topic

• H01M10/44

  Methods for charging or discharging (circuits for charging H02J7/00) · CPC title

• H02J2007/0067

  Electricity · mapped topic

• G01R31/392

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

• G01R31/382

  Arrangements for monitoring battery or accumulator variables, e.g. SoC · CPC title