Battery monitor and open circuit protector

In an electric power distribution system, a battery open circuit monitor for detecting abnormalities in a plurality of serially connected battery cells making up a bank of standby batteries coupled in parallel with a battery charger and a DC powered load and including a circuit for bypassing battery cells experiencing electrical abnormalities in the plurality of serially connected battery cells making up the bank of standby batteries comprising:

• a plurality of back-biased diodes, each of said diodes connected in parallel with a predetermined number of said battery cells for forming designated segments of said serially connected battery cells having a diode connected in parallel with the cells of the designated segment;
• whereby, when one of a battery cell in a segment becomes an open cell, the diode associated with the segment including the open cell becomes forward biased such that the series connection between the adjacent designated segments is closed through said diode and the plurality of serially connected segments of battery cells remains conductive;
• a voltage divider network including a first leg connected to the electrical mid-point of said plurality of serially connected battery cells, said first leg being connected to a galvanometer, and said voltage divider network further including a second leg and a third leg, each of said second and third legs being connected to said galvanometer and respectively, the positive terminal and the negative terminal of said bank of standby batteries;
• said second and said third legs each having included therein a resistor to electrically balance said voltage divider network during normal operation of the bank of standby batteries;
• whereby said galvanometer provides an indication of electrical imbalance relative to said second leg and said third leg and their associated battery cells when a cell experiences an electrical abnormality.