Methods and systems for battery charging management

1. A battery charging system for a vehicle, said system comprising:

a battery charger electrically coupled to at least one battery; and

a plurality of sensors including at least one sensor configured to measure a voltage of the battery, at least one sensor configured to measure a charging current supplied to the battery, and at least one sensor configured to measure a temperature of the battery;

wherein said battery charger is configured to:

to provide charging current to the battery at a substantially constant voltage;

determine a state of charge of the battery using at least one of the plurality of sensors;

determine a rate of gassing of the battery using the temperature and the charging current; and

reduce a charging rate of the battery when the determined rate of gassing exceeds a predetermined rate of gassing.

2. A system in accordance with claim 1 wherein said battery charger is configured to provide charging current to the battery at a substantially constant voltage wherein the voltage is corrected using the measured temperature of the battery.

3. A system in accordance with claim 1 wherein said battery charger is further configured to:

determine a state of charge of the battery using the charging current; and

stop the battery charge when the determined state of charge substantially equals a predetermined state of charge.

4. A system in accordance with claim 1 wherein said battery charger further comprises a battery voltage sensor configured to measure the open circuit voltage of the battery and wherein said battery charger is further configured to determine a state of charge of the battery using the battery voltage sensor.

5. A system in accordance with claim 4 wherein said battery charger is configured to:

temporarily suspend the battery charge;

measure the open circuit voltage of the battery after a predetermined amount of time;

determine the state of charge of the battery using the measured open circuit voltage;

if the state of charge is less than a predetermined state of charge, resume the battery charge for a predetermined period of time;

iteratively determine the state of charge of the battery until the state of charge is equal to of greater than the predetermined state of charge.

6. A system in accordance with claim 1 wherein said battery charger is configured to determine a state of charge using a change of charging current over a predetermined period of time.

7. A system in accordance with claim 1 wherein said battery charger is configured to measure the temperature of a surface of the battery using a temperature sensor in contact with the surface of the battery.

8. A method of charging a battery, said method comprising:

providing a charging current to the battery from a battery charger at a substantially constant voltage determined by a measured temperature of the battery;

determining a state of charge of the battery using the provided charging current;

determining a rate of gassing of the battery using the temperature and the charging current; and

reducing a charging rate of the battery when the determined rate of gassing exceeds a predetermined rate of gassing; and

stopping charging of the battery when the determined state of charge of the battery substantially equals a predetermined state of charge of the battery.

9. A method in accordance with claim 8 wherein determining a state of charge of the battery using the charging current comprises determining a change of charging current over a predetermined period of time.

10. A method in accordance with claim 8 wherein providing charging current to the battery comprises adjusting a voltage output level of the battery charger to deliver a charging current to the battery wherein the level of charging current is at least partially determined by the state of charge of the battery.

11. A method in accordance with claim 8 further comprising measuring the temperature of a surface of the battery.

12. A method in accordance with claim 8 further comprising measuring the temperature of an internal surface of the battery.

13. A method in accordance with claim 8 further comprising:

temporarily suspending the battery charge;

measuring the open circuit voltage of the battery;

determining a state of charge of the battery using the measured open circuit voltage;

if the state of charge is less than a predetermined state of charge, resuming the battery charge for a predetermined period of time;

iteratively determining the state of charge of the battery until the state of charge is equal to or greater than the predetermined state of charge.