STRESS MANAGEMENT OF BATTERY RECHARGE AND METHOD OF STATE CHARGE ESTIMATION

• US 20040222769A1
• Filed: 06/21/2004
• Published: 11/11/2004
• Est. Priority Date: 05/14/2001
• Status: Active Grant

• Current Assignee: Eaton Intelligent Power Limited (Eaton Corporation PLC.)
• Original Assignee: Eaton Industries Co (Eaton Corporation PLC.)
• Inventors: Hunter, Philip Mark, Al-Anbuky, Adnan
• Granted Patent: US 8,040,110 B2
• Time in Patent Office: Days
• US Class Current: 320/128
• CPC Class Codes: H02J 7/0069 Charging or discharging for charge maintenance, battery initiation or rejuvenation
• CPC Class Codes: H02J 7/00714 in response to battery charging or discharging current

Abstract

A method of charging one or more cells including: obtaining one or more cell parameters, or changes in said cell parameters; determining a charge parameter in accordance with the measured cell parameter(s); and supplying energy to the cell(s) in accordance with the determined charge parameter.

Claims

1-19. -19, (canceled)

20. A method of charging one or more cells including:

measuring one or more cell parameters, or changes in said cell parameters;

selecting an allowable temperature rise for the cell(s);

determining a charge parameter in accordance with the measured cell parameter(s) or changes in cell parameters, and in accordance with the selected allowable temperature rise for the cell(s); and

supplying energy to the cell(s) in accordance with the determined charge parameter.

21. A method according to claim 20 wherein energy is being supplied to the cell(s) when the cell parameter is measured.

22. A method according to claim 20 wherein the cell parameter and charge parameter are obtained periodically.

23. A method according to claims 20 wherein the cell parameter is a state of charge of the cell(s).

24. A method according to claim 23 wherein the state of charge of the cell(s) is obtained by measuring one or more measured parameters, and inputting the measured parameter(s) into a state of charge estimation model.

25. A method according to claim 24 further including establishing the state of charge estimation model by previous testing.

26. A method according to claim 20 further including calculating the charge parameter in such a way as to control temperature change of the cell(s) during supply of energy to the cell(s) within predetermined limits.

27. A method according to claim 20, wherein the charge parameter is a charge rate (current).

28. A method according to claim 20 further including acquiring calibration data relating to one or more variable cell parameter(s), or change in said parameter(s);

characterising the calibration data to obtain reference information; and

determining an amount of energy to be supplied to the cell(s),

wherein the charge parameter is determined by relating the allowable temperature rise and energy to be supplied to the reference information.

38. An apparatus adapted to perform the method of claim 20.

39. A computer readable medium containing instructions to enable a computer or micro-processor to perform steps according to claim 20.

29. A method of selecting a charge parameter for one or more cell(s) including:

acquiring data relating one or more variable cell parameter(s), or change in said parameter(s);

characterising the data to obtain reference information;

selecting an allowable temperature rise for the cell(s);

determining an amount of energy to be supplied to the cell(s); and

relating the temperature rise and energy to be supplied to the first reference information to obtain an absolute or relative estimation of the value of the charge parameter.

30. A method of detecting overcharge in one or more cells including:

measuring a variable cell parameter during at least part of a charge of one or more cells;

manipulating the parameter to obtain three or more of its derivatives; and

comparing said derivatives to reference criteria and selecting a result based on said comparison.

31. A method according to claim 30 wherein the derivates include a first, second and third derivative.

32. A method according to claim 30 wherein the derivates include a fourth derivative.

33. A method according to claim 30 wherein the derivates include a second derivative, and the reference criteria include a set non-zero threshold value for the second derivative.

35. A method according to claim 30, wherein the onset of charge saturation is identified.

34. A method of detecting overcharge in one or more cells including:

measuring a variable cell parameter during at least part of a charge of one or more cells;

manipulating the parameter to obtain its second derivative; and

comparing the second derivative to a set non-zero threshold value and selecting a result based on said comparison.

36. A method of obtaining information about the amount of energy to be supplied to one or more cells including:

acquiring a plurality of data relating one or more variable cell and/or ambient parameter(s), or change in said parameter(s), to state of charge of the cell(s);

characterising the data to obtain a Fuzzy Logic model;

measuring, either continuously or periodically, the variable parameter(s), or change in variable parameter(s), during at least a first period of charging of the cell(s); and

inputting the measured variable parameter(s), or change in the measured variable parameter(s), to the Fuzzy Logic model to obtain an absolute or relative estimation of the state of charge of the battery.

37. A method of supplying energy to one or more cells including:

measuring one or more variable cell and/or ambient parameters;

determining an amount of energy to be supplied to the cell(s); and

relating the amount of energy to be supplied to first reference information to obtain a first charge rate parameter for the cell(s);

and, either continuously or periodically during the supply of energy to the cell(s);

measuring one or more variable cell and/or ambient parameters, or changes in said parameters;

during at least a first period of the supply of energy to the cell(s), relating the measured parameter(s) or changes in the measured parameter(s) or a value determined using said parameter(s) to first reference information to obtain an update of the first charge rate parameter; and

during at least a second period of the supply of energy to the cell(s), manipulating at least one of the measured parameter(s), or changes in the measured parameter(s), or a value determined using said parameter(s) and comparing said manipulation to reference criteria to determine the cell(s) response to the energy supplied and from said response choosing either an update of the first charge rate parameter or a second charge rate parameter for the cell(s).