Battery voltage equalizer circuit and method for using the same

A method for battery voltage equalization, comprising:

• detecting a battery voltage of each of a plurality of battery cells that are in a serial connection;
• determining whether the battery voltages for all of the battery cells are higher than an equalization voltage;
• when the battery voltages for all of the battery cells are higher than an equalization voltage, stopping conducting each equalizer part used for equalizing voltage in a parallel connection with each battery cell;
• and
• when the battery voltage for at least one of the battery cell is lower than the equalization voltage, conducting the equalizer part in a parallel connection with the corresponding battery cell in which the battery voltage of the corresponding battery cell is higher than the equalization voltage.

A battery voltage equalizer circuit, comprising:

• a battery voltage equalizer unit, which comprises a plurality of equalizer parts, wherein each equalizer part, coupled to a positive and a negative terminal of a corresponding battery cell among the plurality of battery cells that are in a serial connection, is conducted with an equalization current upon a receipt of the equalization signal;
• a first battery voltage detector unit, coupled to the positive and negative terminals of a first set of the battery cells, generating the equalization signal when any battery cell of the first set of the battery cells reaches an equalization voltage so as to conduct the corresponding equalizer part, and generating a first equalization shutdown signal when all of the first set of the equalizer parts reach the equalization voltage;
• and
• a second battery voltage detector unit, coupled to the positive and negative terminals of a second set of the battery cells of the battery cells, generating the equalization signal when any battery cell of the second set of the battery cells reaches the equalization voltage so as to conduct the corresponding equalizer part and stops the corresponding equalizer parts of the second set of the battery cells from being conducted with the equalization current upon a receipt of the first equalization shutdown signal and when all of the second set of the equalizer parts reaches the equalization voltage.