Method of Selecting a Battery Pack Charging Protocol

Patent metadata

Field	Value
Publication number	US-2016144730-A1
Application number	US-201414553305-A
Country	US
Kind code	A1
Filing date	Nov 25, 2014
Priority date	Nov 25, 2014
Publication date	May 26, 2016
Grant date	—

Abstract

A method is provided for optimizing the charging protocol used when charging the battery pack of an electric vehicle, where optimization is based, in part, on the user's intended departure time and intended travel distance. Based on the user's travel information the process determines (i) an optimal charge level that maximizes the battery pack's lifetime while assuring that there is sufficient energy for the vehicle to travel the intended distance and (ii) an optimal charging rate that maximizes the battery pack's lifetime while assuring that the battery pack is charged to the optimal charge level prior to the intended time of departure. Safety margins may be added to the user's travel information, thus insuring that the car is charged and ready for use if the user decides to leave earlier than expected, or if the travel takes a larger charge than expected.

First claim

What is claimed is:

1 . A method of optimizing a set of charging parameters for a battery pack coupled to an electric drive train of a vehicle, the method comprising the step of:
accepting a set of user determined travel information, wherein said set of user determined travel information is comprised of an intended departure time and an intended travel distance, and wherein said set of user determined travel information is accepted by a system controller of said vehicle; determining an optimal charge level for said battery pack, wherein said optimal charge level maximizes a battery lifetime characteristic of said battery pack while being sufficient to supply energy to said electric drive train for said vehicle to travel said intended travel distance, and wherein said step of determining said optimal charge level is performed by said system controller; determining an optimal charging rate for said battery pack, wherein said optimal charging rate maximizes said battery lifetime characteristic of said battery pack while being sufficient to complete charging of said battery pack to said optimal charge level prior to said intended departure time, and wherein said step of determining said optimal charging rate is performed by said system controller; and charging said battery pack of said vehicle to said optimal charge level, wherein said charging step is performed at said optimal charging rate.

2 . The method of claim 1 , further comprising the steps of:
adding a first safety margin to said intended departure time to define a modified departure time, wherein said first safety margin is added to said intended departure time by said system controller; adding a second safety margin to said intended travel distance to define a modified travel distance, wherein said second safety margin is added to said intended travel distance by said system controller; wherein said optimal charge level determined by said system controller is sufficient to supply energy to said electric drive train for said vehicle to travel said modified travel distance and said optimal charging rate determined by said system controller is sufficient to complete charging of said battery pack prior to said modified departure time.

3 . The method of claim 2 , wherein said modified departure time is earlier than said intended departure time by said first safety margin, and wherein said modified travel distance is greater than said intended travel distance by said second safety margin.

4 . The method of claim 3 , further comprising the step of calculating said second safety margin by multiplying said intended travel distance by a preset percentage.

5 . The method of claim 3 , further comprising the step of accepting a set of user defined safety margins, wherein said set of user defined safety margins are comprised of said first and second safety margins, and wherein said set of user defined safety margins are accepted by said system controller.

6 . The method of claim 3 , further comprising the step of accepting a set of manufacturer defined safety margins, wherein said set of manufacturer defined safety margins is comprised of said first and second safety margins, and wherein said set of manufacturer defined safety margins are accepted by said system controller.

7 . The method of claim 1 , wherein said intended departure time identifies a first expected time of usage for the vehicle after completion of the step of charging said battery pack of said vehicle to said optimal charge level and at said optimal charging rate.

8 . The method of claim 1 , wherein said intended travel distance identifies a total expected travel distance for said vehicle to travel during a period of time occurring between completion of said step of charging said battery pack and a subsequent charging cycle.

9 . The method of claim 1 , wherein said intended travel distance corresponds to a user itinerary, wherein said method further comprises the step of calculating a total travel distance based on said user itinerary, and wherein said optimal charge level maximizes said battery lifetime characteristic of said battery pack while being sufficient to supply energy to said electric drive train for said vehicle to travel said total travel distance.

10 . The method of claim 9 , wherein said user itinerary is comprised of a plurality of locations.

11 . The method of claim 1 , wherein said step of determining said optimal charge level for said battery pack is based on a set of battery pack characteristics and said intended travel distance and said battery lifetime characteristic.

12 . The method of claim 11 , wherein said set of battery pack characteristics is comprised of a set of battery pack conversion efficiency data.

13 . The method of claim 11 , wherein said set of battery pack characteristics is comprised of a set of battery pack energy and DC resistance data.

14 . The method of claim 11 , further comprising the step of inputting said set of battery pack characteristics into said system controller, wherein a vehicle manufacturer performs said step of inputting said set of battery pack characteristics.

15 . The method of claim 11 , further comprising the step of modifying said set of battery pack characteristics based on a monitored age of said battery pack, wherein said modifying step is performed by said system controller.

16 . The method of claim 11 , further comprising the steps of:
monitoring said battery pack to determine a set of performance characteristics of said battery pack, wherein said monitoring step is performed by said system controller; recording said set of performance characteristics of said battery pack; and modifying a baseline set of battery pack characteristics in view of said set of performance characteristics to determine said set of battery pack characteristics, wherein said system controller performs said step of modifying said baseline set of battery pack characteristics to determine said set of battery pack characteristics.

17 . The method of claim 11 , further comprising the step of determining a driving style for a user of said vehicle, wherein said step of determining said optimal charge level for said battery pack is based on said set of battery pack characteristics and said driving style and said intended travel distance and said battery lifetime characteristic.

18 . The method of claim 11 , further comprising the step of determining a set of ambient environmental conditions, wherein said step of determining said optimal charge level for said battery pack is based on said set of battery pack characteristics and said set of ambient environmental conditions and said intended travel distance and said battery lifetime characteristic.

19 . The method of claim 1 , wherein said optimal charge level determined by said system controller is sufficient to supply energy to said electric drive train for said vehicle to travel said intended travel distance and maintain at least a minimum state-of-charge (SOC) until a subsequent charging cycle.

20 . The method of claim 19 , further comprising the step of inputting said minimum SOC into said system controller.

21 . The method of claim 1 , further comprising the step of monitoring a current time, wherein said step of determining said optimal charging rate for said battery pack is based on said optimal charge level and said intended departure time and said current time and said battery lifetime characteristic.

22 . The method of claim 1 , wherei

Assignees

• Atieva Inc

Inventors

• Liu Albert

Classifications

• B60L11/1809 Primary

  Operations & Transport · mapped topic

• Y02T10/72

  Electric energy management in electromobility · CPC title

• Y02T10/70

  Energy storage systems for electromobility, e.g. batteries · CPC title

• B60L2260/54

  Energy consumption estimation · CPC title

• B60L2250/14

  by input of vehicle departure time · CPC title