Battery operated computer having improved battery monitor and cell reversal protection circuit

A battery-operated, portable computer comprising:

• a battery connected to said computer for supplying electrical energy to operate said computer, said battery comprising a plurality of battery banks connected in series, each bank comprising a like number of matched battery cells connected in series;
• voltage monitoring means connected to said banks for measuring respective bank voltages across each of said banks during operation of said computer, said voltage monitoring means comprising first means for generating a low battery warning signal when the bank voltage across any one of said banks drops below a predetermined first value corresponding to a battery charge level allowing said computer to save volatile data and power down under program control, said voltage monitoring means further comprising second means for generating a cutoff signal when the bank voltage across any one of said banks drops below a predetermined second value lower than said first value, said second value corresponding to a voltage level below which cell polarity reversal is eminent;
• shutdown means connected to said monitoring means for receiving said warning signal and, in response thereto, initiating saving volatile data and powering down said computer;
• and
• cell reversal protection circuit means connected to said monitoring means for receiving said cutoff signal and, in response thereto, immediately disconnecting said battery from said computer to prevent cell polarity reversal from occurring.