Battery system and method for system state of charge determination
AssigneeRobert Bosch GmbH
InventorsJohn F. Christensen, Jasim Ahmed
Life of this patent
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Abstract
A battery system and method of providing a state of charge of for the system in one embodiment includes at least one first cell, the at least one first cell having a first battery chemistry exhibiting a first open circuit potential, and at least one second cell in series connection with the at least one first cell, the at least one second cell having a second battery chemistry exhibiting a second open circuit potential, wherein the at least one first cell exhibits an open circuit potential with a center slope that is greater than the center slope of the open circuit potential exhibited by the at least one second cell.
Claims19
A battery system comprising:
- at least one first cell, the at least one first cell exhibiting a first open circuit potential curve;
- and
- at least one second cell in series connection with the at least one first cell, the at least one second cell exhibiting a second open circuit potential curve, wherein the at least one first cell and the at least one second cell have different battery chemistry,
- wherein the at least one first cell exhibits an open circuit potential curve with a slope that is greater than the slope of the open circuit potential curve exhibited by the at least one second cell over a range of at least 40 percent state of charge to at least 60 percent state of charge, and wherein the system is configured to:
- associate each of a plurality of first cell voltages with one of a plurality of SOC conditions;
- obtain the voltage of the first cell;
- compare the obtained voltage with the associated plurality of first cell voltages;
- and
- determine the SOC of the battery system based upon the comparison.
A method of determining the state of charge (SOC) of a battery system comprising:
- providing a battery system with at least one first battery cell and at least one second battery cell, wherein the at least one first battery cell exhibits an open circuit potential curve with a slope that is greater than the slope of the open circuit potential curve exhibited by the at least one second battery cell over a range of at least 40 percent SOC to at least 60 percent SOC;
- and wherein the at least one first battery cell and the at least one second battery cell have different battery chemistry,
- associating each of a plurality of first battery cell voltages with one of a plurality of SOC conditions;
- storing the associated plurality of first battery cell voltages and plurality of SOC conditions;
- obtaining the voltage of the first battery cell;
- comparing the obtained voltage with the stored plurality of first battery cell voltages;
- and
- determining the SOC of the battery system based upon the comparison.
A battery system comprising:
- at least one first cell, the at least one first cell exhibiting a first open circuit potential curve over a first range of state of charge (SOC);
- and
- at least one second cell in series connection with the at least one first cell, the at least one second cell exhibiting a second open circuit potential curve over the first range of SOC, wherein the at least one first cell and the at least one second cell have different battery chemistry,
- wherein the slope of the second open circuit potential curve is positive and the slope of the first open circuit potential curve is less than the slope of the second open circuit potential curve, and wherein the system is configured to:
- associate each of a plurality of second cell voltages with one of a plurality of SOC conditions;
- obtain the voltage of at least one of the at least one second cell;
- compare the obtained voltage with the associated plurality of second cell voltages;
- and
- determine the SOC of the battery system based upon the comparison.
Dependencies are inferred from the claim text.