Maintaining a vehicle battery

• US 9,789,784 B2
• Filed: 05/13/2015
• Issued: 10/17/2017
• Est. Priority Date: 05/13/2015
• Status: Expired due to Fees

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Tistle, Cathleen, Eifert, Mark, Semanson, Christopher
• Primary Examiner(s): Ngo, Brian
• Application Number:
  US14/710,936
• Publication Number:
  US 20160332533A1
• Time in Patent Office: 888 Days
• Field of Search: 320107, 320150, 320152, 320153, 320157, 320160, 320163
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/80 Time limits
• CPC Class Codes: B60L 53/62 in response to charging parameters, e.g. current, voltage or electrical charge
• CPC Class Codes: B60L 58/15 Preventing overcharging
• CPC Class Codes: B60L 58/25 by controlling the electric load
• CPC Class Codes: H01M 10/06 Lead-acid accumulators semi-lead accumulators H01M10/20
• CPC Class Codes: H01M 10/443 in response to temperature
• CPC Class Codes: H01M 10/486 for measuring temperature
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: H02J 2310/48 for electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: H02J 7/00714 in response to battery charging or discharging current
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: H02J 7/007194 of the battery
• CPC Class Codes: H02J 7/04 Regulation of charging current or voltage
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles
• CPC Class Codes: Y02T 90/16 Information or communication technologies improving the operation of electric vehicles

Abstract

A method is provided for determining a lower voltage set-point, an upper voltage set-point, a temperature-dependent upper current set-point, a time limit value, and a lower current hysteresis threshold set-point based on a measured temperature of a battery. A charge current from a battery charging circuit is provided. If a charge voltage is above the lower voltage set-point and below the upper voltage set-point and the charge current exceeds the temperature-dependent upper current set-point, timer is started. If the timer reaches a time limit value while the charge current exceeds the temperature-dependent upper current set-point and the charge voltage is between the lower voltage set-point and the upper voltage set-point, the charge current is reduced.

Claims

1. A method, comprising:

determining a lower voltage set-point, an upper voltage set-point, a temperature-dependent upper current set-point, a time limit value, and a lower current hysteresis threshold set-point based on a measured temperature of a battery;

providing a charge current from a battery charging circuit;

determining if a charge voltage is above the lower voltage set-point and below the upper voltage set-point; and

determining whether the charge current exceeds the temperature-dependent upper current set-point, and if so,

starting a timer if, in addition to the charge current exceeding the temperature-dependent upper current set-point, the charge voltage is between the lower voltage set-point and the upper voltage set-point; and

,

if the timer reaches the time limit value while the charge current exceeds the temperature-dependent upper current set-point and the charge voltage is between the lower voltage set-point and the upper voltage set-point,

reducing the charge current below the lower current hysteresis threshold set-point when the timer expires.

2. The method of claim 1, further comprising incrementally reducing the charge current to substantially no current when the timer exceeds the time limit.

3. The method of claim 1, further comprising decreasing the temperature-dependent upper current set-point as the temperature of the battery increases.

4. The method of claim 1, wherein any one of the lower voltage set-point, the upper voltage set-point, the time limit value, and the temperature-dependent upper current set-point are predetermined.

5. The method of claim 1, wherein the battery is a vehicle battery.

6. The method of claim 1, wherein the battery is a flooded lead acid (FLA) battery.

7. A system comprising a computer, the computer being configured to charge a battery, and further configured to:

determine a lower voltage set-point, an upper voltage set-point, a temperature-dependent upper current set-point, a time limit value, and a lower current hysteresis threshold set-point from a temperature of the battery;

provide a charge current to the battery;

determine when the charge current exceeds the temperature-dependent upper current set-point and a charge voltage is in between the lower voltage set-point and the upper voltage set-point, and if so, start a timer while the charge current exceeds the temperature-dependent upper current set-point and the charge voltage is between the lower voltage set-point and the upper voltage set-point; and

determine if the timer reaches the time limit value while the charge current exceeds the temperature-dependent upper current set-point and the charge voltage is between the lower voltage set-point and the upper voltage set-point and if so, reduce the charge current below the lower current hysteresis threshold set-point when the timer expires.

8. The system of claim 7, wherein the charge current is incrementally reduced to substantially no current after the timer exceeds the timer expires.

9. The system of claim 7, wherein the temperature-dependent upper current set-point is decreased as the temperature of the battery is increased.

10. The system of claim 7, wherein the battery is a vehicle battery.

11. The system of claim 7, wherein the battery charging circuit is in a vehicle.

12. The system of claim 7, wherein the battery is a flooded lead acid (FLA) battery.

13. The system of claim 7, wherein an electricity source is at least one from a power grid, a vehicle alternator, a regenerative braking system, and a high voltage battery.