Cooling strategy for battery systems

Patent metadata

Field	Value
Publication number	US-10099562-B2
Application number	US-201514788223-A
Country	US
Kind code	B2
Filing date	Jun 30, 2015
Priority date	Oct 15, 2014
Publication date	Oct 16, 2018
Grant date	Oct 16, 2018

Abstract

Embodiments describe a battery system that includes a first battery module coupled to a regenerative braking system and a control module that controls operation of the battery system by: determining a predicted driving pattern over a prediction horizon using a driving pattern recognition model based in part on a battery current and a previous driving pattern; determining a predicted battery resistance of the first battery module over the prediction horizon using a recursive battery model based in part on the predicted driving pattern, the battery current, a present bus voltage, and a previous bus voltage; determining a target trajectory of a battery temperature of the first battery module over a control horizon using an objective function; and controlling magnitude and duration of electrical power supplied from the regenerative such that a predicted trajectory of the battery temperature is guided toward the target trajectory of the battery temperature during the control horizon.

First claim

The invention claimed is:

1. A battery system configured to be used in an automotive vehicle, wherein the battery system comprises:
a first battery module electrically coupled to a regenerative braking system; and
a control module configured to control operation of the battery system by:
determining a predicted driving pattern of the automotive vehicle over a prediction horizon using a driving pattern recognition model based at least in part on a battery current and a previous driving pattern of the automotive vehicle;
determining a predicted battery resistance of the first battery module over the prediction horizon using a recursive battery model based at least in part on the predicted driving pattern, the battery current, a present bus voltage, and a previous bus voltage;
determining a target trajectory of a battery temperature of the first battery module over a control horizon using an objective function to balance effects of the battery temperature on aspects of the first battery module; and
controlling magnitude and duration of electrical power supplied from the regenerative braking system to the first battery module such that a predicted trajectory of the battery temperature is guided toward the target trajectory of the battery temperature during the control horizon.

2. The battery system of claim 1 , comprising a second battery module electrically coupled in parallel with the first battery module, wherein the second battery module is configured to be electrically coupled to the regenerative braking system and has a different battery chemistry from the first battery module.

3. The battery system of claim 2 , wherein the first battery module comprises a lithium ion battery and the second battery module comprises a lead-acid battery.

4. The battery system of claim 1 , wherein the control module is configured to determine the predicted driving pattern of the automotive vehicle by:
identifying a portion of the previous driving pattern as a basis of the predicted driving pattern based at least in part on a profile of the battery current, wherein the previous driving pattern comprises previously determined battery currents of the first battery module; and
adjusting the portion of the previous driving pattern based on operational parameters of the automotive vehicle.

5. The battery system of claim 1 , wherein the control module is configured to determine the predicted battery resistance of the first battery module by:
determining a change between the previous bus voltage and the present bus voltage;
determining the predicted driving pattern as an average current; and
determining the predicted battery resistance as an average resistance based at least in part on the change between the previous bus voltage and the present bus voltage, the average current, and the battery current.

6. The battery system of claim 1 , wherein the control module is configured to determine the target trajectory of the battery temperature by:
determining a plurality of factor target trajectories of the battery temperature, wherein each of the plurality of factor target trajectories is associated with one aspect of the first battery module; and
determining the target trajectory by weighing each of the plurality of factor target trajectories using the objective function.

7. The battery system of claim 1 , wherein the control module is configured to determine the target trajectory of the battery temperature by:
determining a battery life target trajectory of the battery temperature using a battery life model based at least in part on the predicted driving pattern and a current age of the first battery module;
determining a fuel economy target trajectory of the battery temperature using a fuel economy model based at least in part on the predicted driving pattern and the battery current; and
determining the target trajectory of the battery temperature by combining the battery life target trajectory and the fuel economy target trajectory based on the objective function.

8. The battery system of claim 1 , comprising:
an electric motor of the regenerative braking system configured to convert mechanical energy produced by movement of the automotive vehicle into electrical energy; or
an alternator of the regenerative braking system configured to convert mechanical energy produced by an internal combustion engine of the automotive vehicle into electrical energy.

9. The battery system of claim 1 , comprising a thermal system configured to facilitate cooling the battery system, wherein the control module is configured to supplement the thermal system by reducing amount of charging and discharging performed by the first battery module.

10. The battery system of claim 1 , wherein the control horizon comprises a first plurality of future time steps and the prediction horizon comprises a second plurality of future time steps, wherein the first plurality is less than or equal to the second plurality.

11. A tangible non-transitory, computer readable medium of a lithium ion battery system configured to store instructions executable by a processor in an automotive vehicle, wherein the instructions comprise instructions to:
determine, using the processor, temperature of a lithium ion battery module;
determine, using the processor, a temperature threshold;
instruct, using the processor, an electrical energy generator to output a high electrical power when the temperature of the lithium ion battery module is not greater than the temperature threshold to enable the lithium ion battery system to utilize a first amount of storage capacity to capture generated electrical energy; and
instruct, using the processor, the electrical energy generator to output a low electrical power when the temperature of the lithium ion battery module is greater than the temperature threshold to enable the lithium ion battery system to utilize a second amount of storage capacity to capture generated electrical energy, wherein the second amount is less than the first amount.

12. The tangible non-transitory, computer-readable medium of claim 11 , comprising instructions to, when the temperature of the lithium ion battery module is not greater than the temperature threshold:
determine a target trajectory of the temperature of the lithium ion battery module over a control horizon;
determine battery parameter setpoints based at least in part on a thermal predictive model, wherein the thermal predictive model is configured to describe a relationship between the battery parameter setpoints and a predicted trajectory of the temperature over a prediction horizon; and
instruct the lithium ion battery system to implement the battery parameter setpoints such that the predicted trajectory of the temperature is guided toward the target trajectory, maintained below the temperature threshold, or both over the control horizon.

13. The tangible non-transitory, computer-readable medium of claim 12 , comprising instructions to instruct a relay to electrically disconnect the lithium ion battery module from the lithium ion battery system when the temperature is greater than the temperature threshold.

14. The tangible non-transitory, computer-readable medium of claim 12 , comprising instructions to:
determine, using the processor, a predicted driving pattern of the automotive vehicle over the prediction horizon based at least in part on a driving pattern recognition model;
determine, using the processor, a predicted battery resistance of the lithium ion battery module over the prediction horizon based at least in part on a recursive battery model; and
determine, using the processor, the predicted traje

Assignees

• Johnson Controls Tech Co

Inventors

• Jin Zhihong H
• Sisk Brian C
• Obasih Kem M
• Johnson Mark R
• Wyatt Perry M
• Aliyev Timur L
• Zhang Zhenli

Classifications

• B60L50/60

  using power supplied by batteries (in combination with fuel cells B60L50/75) · CPC title

• B60L2240/36

  Temperature of vehicle components or parts · CPC title

• B60L2240/423

  Torque · CPC title

• B60L2240/545

  Temperature · CPC title

• B60L58/15

  Preventing overcharging · CPC title