Charge/discharge management in electrochemical cells, including partial cycle control
Electrochemical cell and battery management systems are generally provided. The systems can comprise an electrochemical cell and a controller. In some cases, the controller can be used to control various aspects of the charge and/or discharge of the electrochemical cell. In some cases, the system can comprise one or more strings of cells.
1. An electrochemical cell management system comprising:
an electrochemical cell; and
at least one controller configured to:
control the cell such that the cell is charged over a first state of charge range having breadth of at least 20%,
wherein an average charging rate over a first portion of the first state of charge range is lower than an average charging rate over a second portion of the first state of charge range,
wherein the first portion spans at least 2% of the first state of charge range and the second portion spans at least 2% of the first state of charge range,
wherein the first portion occurs before the second portion, and
wherein the at least one controller is configured to:
control the cell such that the cell is discharged over a second state of charge range having breadth of at least 2% and at most 90%, and then discharged over a third state of charge range having breadth of at least 2%,
wherein an average discharging rate over the second state of charge range is at least 2 times an average discharging rate over the third state of charge range.
2. An electrochemical cell management system comprising:
an electrochemical cell; and
at least one controller configured to:
control the cell such that the cell is charged over a first state of charge range having breadth of at least 2% and at most 90%, and then charged over a second state of charge range,
wherein an average charging rate over the first state of charge range is at most 0.5 times an average charging rate over the second state of charge range,
wherein the at least one controller is configured to:
control the cell such that the cell is discharged over a third state of charge range having breadth of at least 2% and at most 90%, and then discharged over a fourth state of charge range having breadth of at least 2%,
wherein an average discharging rate over the third state of charge range is at least 2 times an average discharging rate over the fourth state of charge range.
3. An electrochemical cell management system comprising:
an electrochemical cell; and
at least one controller configured to:
control the cell such that the cell is charged over a first state of charge range having breadth of at least 20%,
wherein an average charging rate over a first portion of the first state of charge range is lower than an average charging rate over a second portion of the first state of charge range,
wherein the first portion spans at least 2% of the first state of charge range and the second portion spans at least 2% of the first state of charge range,
wherein the first portion occurs before the second portion, and
wherein the at least one controller is configured to:
control the cell such that the cell is discharged over a second state of charge range having breadth of at least 2% and at most 90%, then discharged over a third state of charge range having breadth of at least 2%, and then discharged over a fourth state of charge range having breadth of at least 2%,
wherein an average discharging rate over the second state of charge range is higher than an average discharging rate over the third state of charge range, and
wherein the average discharging rate over the third state of charge range is higher than an average discharging rate over the fourth state of charge range.
4. The electrochemical cell management system of claim 1 , wherein the cell is discharged over the third state of charge range after the cell is charged over the second state of charge range.
5. The electrochemical cell management system of claim 2 , wherein the at least one controller is configured to:
control the cell such that the cell is discharged over a third state of charge range having breadth of at least 2% and at most 90%, then discharged over a fourth state of charge range having breadth of at least 2%, and then discharged over a fifth state of charge range having breadth of at least 2%,
wherein an average discharging rate over the third state of charge range is higher than an average discharging rate over the fourth state of charge range, and
wherein the average discharging rate over the fourth state of charge range is higher than an average discharging rate over the fifth state of charge range.
6. The electrochemical cell management system of claim 2 , wherein the cell is discharged over the third state of charge range after the cell is charged over the second state of charge range.
7. An electrochemical cell management system comprising:
an electrochemical cell; and
at least one controller configured to:
control the cell such that the cell is charged over a first state of charge range having breadth of at least 2% and at most 90%, and then charged over a second state of charge range,
wherein an average charging rate over the first state of charge range is at most 0.5 times an average charging rate over the second state of charge range, and
wherein the at least one controller is configured to:
control the cell such that the cell is discharged over a fourth state of charge range having breadth of at least 2% and at most 90%, and then discharged over a fifth state of charge range having breadth of at least 2%,
wherein an average discharging rate over the fourth state of charge range is at least 2 times an average discharging rate over the fifth state of charge range.
8. An electrochemical cell management method comprising:
controlling an electrochemical cell such that the cell is charged over a first state of charge range having breadth of at least 20%,
wherein an average charging rate over a first portion of the first state of charge range is lower than an average charging rate over a second portion of the first state of charge range,
wherein the first portion spans at least 2% of the first state of charge range and the second portion spans at least 2% of the first state of charge range,
wherein the first portion occurs before the second portion,
wherein the method comprises controlling the cell such that the cell is discharged over a second state of charge range having breadth of at least 2% and at most 90%, and then discharged over a third state of charge range having breadth of at least 2%, and
wherein an average discharging rate over the second state of charge range is at least 2 times an average discharging rate over the third state of charge range.
9. An electrochemical cell management method comprising:
controlling an electrochemical cell such that the cell is charged over a first state of charge range having breadth of at least 2% and at most 90%, and then charged over a second state of charge range,
wherein an average charging rate over the first state of charge range is at most 0.5 times an average charging rate over the second state of charge range,
wherein the method comprises controlling the cell such that the cell is discharged over a third state of charge range having breadth of at least 2% and at most 90%, and then discharged over a fourth state of charge range having breadth of at least 2%, and
wherein an average discharging rate over the third state of charge range is at least 2 times an average discharging rate over the fourth state of charge range.
10. An electrochemical cell management method, comprising:
controlling an electrochemical cell such that the cell is charged over a first state of charge range having breadth of at least 20%,
wherein an average charging rate over a first portion of the first state of charge range is lower than an average charging rate over a second portion of the first state of charge range,
wherein the first portion spans at least 2% of the first state of charge range and the second portion spans at least 2% of the first state of charge range,
wherein the first portion occurs before the second portion,
wherein the method comprises controlling the cell such that the cell is discharged over a second state of charge range having breadth of at least 2% and at most 90%, then discharged over a third state of charge range having breadth of at least 2%, and then discharged over a fourth state of charge range having breadth of at least 2%,
wherein an average discharging rate over the second state of charge range is higher than an average discharging rate over the third state of charge range, and
wherein the average discharging rate over the third state of charge range is higher than an average discharging rate over the fourth state of charge range.
11. The electrochemical cell management method of claim 8 , wherein the cell is discharged over the third state of charge range after the cell is charged over the second state of charge range.
12. The electrochemical cell management method of claim 9 , comprising:
controlling the cell such that the cell is discharged over a third state of charge range having breadth of at least 2% and at most 90%, then discharged over a fourth state of charge range having breadth of at least 2%, and then discharged over a fifth state of charge range having breadth of at least 2%,
wherein an average discharging rate over the third state of charge range is higher than an average discharging rate over the fourth state of charge range, and
wherein the average discharging rate over the fourth state of charge range is higher than an average discharging rate over the fifth state of charge range.
13. The electrochemical cell management method of claim 9 , wherein the cell is discharged over the third state of charge range after the cell is charged over the second state of charge range.
14. An electrochemical cell management method, comprising:
controlling an electrochemical cell such that the cell is charged over a first state of charge range having breadth of at least 2% and at most 90%, and then charged over a second state of charge range,
wherein an average charging rate over the first state of charge range is at most 0.5 times an average charging rate over the second state of charge range, and
controlling the cell such that the cell is discharged over a fourth state of charge range having breadth of at least 2% and at most 90%, and then discharged over a fifth state of charge range having breadth of at least 2%,
wherein an average discharging rate over the fourth state of charge range is at least 2 times an average discharging rate over the fifth state of charge range.