SYSTEMS AND METHODS FOR DETERMINING CELL CAPACITY VALUES IN A MULTI-CELL BATTERY
First Claim
Patent Images
1. A method for determining cell capacity values for a vehicle battery pack comprising:
- receiving, at a processor, sensor data indicative of the voltage of the pack, one or more currents of the pack, and voltages for a plurality of cells in the pack;
determining a first set of state of charge values for the plurality of cells using a voltage-based strategy on the sensor data when the state of charge of the pack is below a lower threshold value;
determining a second set of state of charge values for the plurality of cells using a voltage-based strategy on the sensor data when the state of charge of the pack is above an upper threshold value;
determining a charge count value for the pack using the sensor data, wherein the charge count is started when the state of charge of the pack is below the lower threshold value; and
wherein the charge count is stopped when the state of charge of the pack is above the upper threshold value;
generating difference values using the differences between the state of charge values in the first and the second sets;
calculating cell capacity values by dividing the charge count value by the difference values; and
storing the cell capacity values in a memory.
3 Assignments
0 Petitions
Accused Products
Abstract
Systems and methods to determine cell capacities of a vehicle battery pack. Cell capacities may be determined using state of charge (SOC) estimates for the cells and a charge count for the battery pack. The SOC estimates may be determined when the SOC of the battery pack is below a lower threshold and above an upper threshold. Error values may also be generated for the cell capacity values.
-
Citations
20 Claims
-
1. A method for determining cell capacity values for a vehicle battery pack comprising:
-
receiving, at a processor, sensor data indicative of the voltage of the pack, one or more currents of the pack, and voltages for a plurality of cells in the pack; determining a first set of state of charge values for the plurality of cells using a voltage-based strategy on the sensor data when the state of charge of the pack is below a lower threshold value; determining a second set of state of charge values for the plurality of cells using a voltage-based strategy on the sensor data when the state of charge of the pack is above an upper threshold value; determining a charge count value for the pack using the sensor data, wherein the charge count is started when the state of charge of the pack is below the lower threshold value; and
wherein the charge count is stopped when the state of charge of the pack is above the upper threshold value;generating difference values using the differences between the state of charge values in the first and the second sets; calculating cell capacity values by dividing the charge count value by the difference values; and storing the cell capacity values in a memory. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. A vehicle controller comprising:
-
an interface configured to receive sensor data from a plurality of voltage and current sensors, wherein the sensor data is indicative of the voltage of the pack, the currents of the pack, and the voltages for a plurality of cells in the pack; a voltage-based state of charge generator configured to generate; a state of charge value for the pack, a first set of state of charge values for the plurality of cells, when the state of charge of the pack is below a lower threshold value, and a second set of state of charge values for the plurality of cells, when the state of charge of the battery pack is above an upper threshold value; a charge counter configured to determine a charge count value for the battery pack using the sensor data, wherein the charge count is started when the state of charge of the battery pack is below the lower threshold value, and wherein the charge count is stopped when the state of charge of the battery pack is above the upper threshold value; a rest timer configured to determine a rest time for the battery pack; a difference evaluator configured to generate difference values using the differences between the state of charge values in the first and the second sets; and a cell capacity calculator configured to calculate cell capacity values by dividing the charge count value by the difference values. - View Dependent Claims (9, 10, 11, 12, 13, 14)
-
-
15. A system for determining cell capacity values for a vehicle battery pack comprising:
-
a vehicle battery pack comprising a plurality of cells; voltage sensors configured to measure the voltage of the pack and the cells; current sensors configured to measure the currents into and out of the pack; and a processing circuit comprising an interface that receives voltage data from the voltage sensors and current data from the current sensors, a processor, and a memory coupled to the processor, wherein the memory stores executable instructions that, when executed by the processor, cause the processor to; determine a first set of state of charge values for the plurality of cells using a voltage-based strategy on the voltage data measured when the state of charge of the pack is below a lower threshold value, determine a second set of state of charge values for the plurality of cells using a voltage-based strategy on the sensor data on the voltage data measured when the state of charge of the pack is above an upper threshold value, determine a charge count using the current data, calculate cell capacity values using the charge count and the first and second sets of state of charge values, and store the cell capacity values in the memory. - View Dependent Claims (16, 17, 18, 19, 20)
-
Specification