Battery charger with automatic voltage detection

A method for charging a battery connected to a battery charger by way of a pair of battery cables, the method comprising the steps of:

• (a) automatically measuring the open circuit voltage of a battery connected to the battery charger;
• (b) automatically determining the nominal battery voltage of the battery connected to the battery cables as a function of the open circuit voltage and if the open circuit voltage is less than a predetermined voltage, the nominal battery voltage is determined as a function of a measured peak ripple voltage across the battery in response to a test current;
• and
• (c) automatically charging the battery in accordance with the nominal battery voltage of the battery connected to the battery cables, as determined in step (b).

A battery charger comprising:

• a pair of battery charger terminals;
• an automatic voltage detection system for automatically determining the nominal voltage of the battery connected across the battery charger terminals and automatically determining the nominal voltage of the battery connected across the battery charger terminals by measuring an open circuit voltage of the battery by determining the nominal voltage of the battery based upon the open circuit voltage of the battery when the open circuit voltage is greater than or equal to a predetermined value and when said open circuit voltage is less than said predetermined value, determining the nominal voltage of the battery as a function of a measured peak ripple voltage across the battery in response to a test current;
• and
• a charging system for automatically charging the battery as a function of the nominal voltage determined by said automatic voltage detection system.