Electrified powertrain with method for determining battery limits based on cell factors

Patent metadata

Field	Value
Publication number	US-2022271552-A1
Application number	US-202117184968-A
Country	US
Kind code	A1
Filing date	Feb 25, 2021
Priority date	Feb 25, 2021
Publication date	Aug 25, 2022
Grant date	—

Abstract

A method for adapting a usage level of a battery pack includes measuring cell sense data for each respective battery cell using a cell sense circuit, the cell sense data including a cell voltage, current, and temperature. The method includes processing the cell sense data, for each respective battery cell, through multiple battery state functions of a controller to generate numeric cell degradation values (CDVs). The battery state functions are calibrated relationships of the cell sense data to predetermined battery fault conditions. Thereafter, the method includes automatically adapting the usage level of the battery pack during operation of the battery pack, via the controller, based on the numeric CDVs. An electric powertrain system includes the battery pack, cell sense circuit, a rotary electric machine, and a controller configured to execute the above method.

First claim

1 . A method for adapting a usage level of a battery pack having a plurality of battery cells, the method comprising:
measuring cell sense data for each respective one of the battery cells using a cell sense circuit, the cell sense data including a cell voltage, a cell current, and a cell temperature; processing the cell sense data, for each respective battery cell of the plurality of battery cells, through multiple battery state functions of a controller to thereby generate a plurality of numeric cell degradation values (CDVs), wherein the multiple battery state functions are calibrated relationships of the cell sense data to predetermined battery fault conditions; and automatically adapting the usage level of the battery pack during operation of the battery pack, via the controller, based on the numeric CDVs.

2 . The method of claim 1 , wherein the predetermined battery fault conditions include an intermittent or sustained electrical short condition within the respective battery cell, and wherein the multiple battery state functions include an electrical short function indicative of the intermittent or sustained electrical short condition.

3 . The method of claim 1 , wherein the predetermined battery fault conditions include active material plating of the respective battery cell, and wherein the multiple battery state functions include a plating function indicative of a level of the active material plating.

4 . The method of claim 1 , wherein the predetermined battery fault conditions include a diminished energy holding capacity of the respective battery cell, and wherein the multiple battery state functions include a capacity function indicative of the diminished energy holding capacity.

5 . The method of claim 1 , wherein the predetermined battery fault conditions include an elevated or reduced temperature of the respective battery cell, and wherein the multiple battery state functions include a temperature function indicative of the elevated or reduced temperature.

6 . The method of claim 1 , wherein the predetermined battery fault conditions include an electrolyte leakage condition of the respective battery cell, and wherein the multiple battery state functions include an electrolyte leakage function indicative of the electrolyte leakage condition.

7 . The method of claim 1 , wherein automatically adapting the usage level of the battery pack includes modifying calibrated charging limits, charging rates, and/or thermal limits of the battery pack during a charging operation of the battery pack.

8 . The method of claim 1 , wherein automatically adapting the usage level of the battery pack includes modifying calibrated discharging limits and/or thermal limits of the battery pack during a discharging operation of the battery pack.

9 . The method of claim 1 , wherein automatically adapting the usage level of the battery pack during operation of the battery pack includes modifying a charging behavior of an offboard charging station and/or an onboard solar panel during a charging operation of the battery pack.

10 . The method of claim 9 , wherein processing the cell sense data through the multiple battery state functions includes processing the cell sense data and at least one additional powertrain control factor of the motor vehicle through an arbitration logic block of the controller, and wherein automatically adapting the usage level of the battery pack includes assigning a relative weight to each respective one of the multiple battery state functions and the additional powertrain control factor via the arbitration logic block.

11 . The method of claim 10 , wherein the additional powertrain control factor includes a life modeling limit, an energy/regeneration optimization limit, or a navigation/route planning-based limit of the motor vehicle.

12 . An electric powertrain system comprising:
a battery pack having a plurality of battery cells and a cell sense circuit, the cell sense circuit being configured to measure cell sense data for each respective one of the battery cells; a rotary electric machine that is electrically connected to the battery pack, wherein the battery pack is configured to supply electrical energy to the rotary electric machine in a discharging mode, and to receive electrical energy from the rotary electric machine, an offboard charging station, and/or a solar panel in a charging mode; and a controller in communication with the cell sense circuit and the rotary electric machine, wherein the controller is configured to:
receive the cell sense data for each respective one of the battery cells from the cell sense circuit, the cell sense data including a cell voltage, a cell current, and a cell temperature;
process the cell sense data, for each respective battery cell of the plurality of battery cells, through multiple battery state functions to thereby generate a plurality of numeric cell degradation values (CDVs), wherein the multiple battery state functions are calibrated relationships of the cell sense data to predetermined battery fault conditions; and
automatically adapt the usage level of the battery pack during operation of the battery pack based on the numeric CDVs.

13 . The electric powertrain system of claim 12 , wherein the predetermined battery fault conditions include an intermittent or sustained electrical short condition within the respective battery cell, and wherein the multiple battery state functions include an electrical short function indicative of the intermittent or sustained electrical short condition.

14 . The electric powertrain system of claim 12 , wherein the predetermined battery fault conditions include an active material plating condition and/or an electrolyte leakage condition of the respective battery cell, and wherein the multiple battery state functions include a plating function indicative of a level of the active material plating condition and/or an electrolyte leakage function indicative of the electrolyte leakage condition, respectively.

15 . The electric powertrain system of claim 12 , wherein the predetermined battery fault conditions include a diminished energy holding capacity of the respective battery cell, and wherein the multiple battery state functions include a capacity function indicative of the diminished energy holding capacity.

16 . The electric powertrain system of claim 12 , wherein automatically adapting the usage level of the battery pack includes modifying calibrated charging limits, charging rates, and/or thermal limits of the battery pack during a charging cycle of the battery pack using the offboard charging station and/or the onboard solar panel.

17 . The electric powertrain system of claim 12 , wherein the controller is configured to process the cell sense data and at least one additional powertrain control factor through an arbitration logic block, and to automatically adapt the usage level of the battery pack in part by assigning a relative weight to each respective one of the multiple battery state functions and the additional powertrain control factor via the arbitration logic block.

18 . The electric powertrain system of claim 12 , wherein the at least one additional powertrain control factor includes a life modeling limit and/or an energy/regeneration optimization limit.

19 . The electric powertrain system of claim 12 , wherein the rotary electric machine is an electric propulsion motor for a motor vehicle, and wherein the additional powertrain control factor includes a navigation/route planning-based limit of the motor vehicle in which a

Assignees

• Gm Global Tech Operations Llc

Inventors

• Gibbs James C
• Zettel Andrew M
• Goodman Calvin
• Nagappala Rajesh

Classifications

• H02J7/977

  of the battery · CPC title

• H02J7/84

  Control of state of health [SOH] · CPC title

• H02J7/82

  Control of state of charge [SOC] · CPC title

• H02J7/60

  including safety or protection arrangements · CPC title

• H02J7/50

  acting upon multiple batteries simultaneously or sequentially · CPC title