Battery monitoring system

摘要

A battery monitoring system, comprises a battery state detection circuit that detects battery states of a plurality of battery cells that are connected in series, based on respective cell voltages of the plurality of battery cells, and a control circuit that monitors state of a battery cell, based on each cell voltage of the plurality of battery cells. The control circuit inputs pseudo voltage information to the battery state detection circuit, and thereby diagnoses whether or not the battery state detection circuit is operating normally.

主权项

1. A battery monitoring system, comprising:
an integrated circuit that includes a voltage measurement unit measuring a cell voltage value of each of a plurality of battery cells connected in series; a plurality of voltage measurement lines that connect positive and negative electrodes of the plurality of battery cells and the integrated circuit; and a control circuit that monitors state of each of the plurality of battery cells, based on the cell voltage value measured by the voltage measurement unit, wherein: the integrated circuit includes a pseudo voltage generation unit that generates a pseudo voltage; the voltage measurement unit includes:
a selection circuit that selects a pair of voltage measurement lines connected to a positive and a negative electrodes of a battery cell that is to be a subject of measurement; anda detection circuit that detects a voltage between the pair of voltage measurement lines selected by the selection circuit; the control circuit inputs the pseudo voltage, instead of the voltage between the pair of voltage measurement lines, to input terminals of the selection circuit and diagnoses state of selection by the selection circuit based on a voltage value detected by the detection circuit; a resistor is provided to each of the plurality of voltage measurement lines: the integrated circuit includes a discharge circuit that discharges the battery cell so that a discharge current flows in the resistor, as the pseudo voltage generation unit; and the control circuit diagnoses the state of selection by the selection circuit, based on a first voltage that is detected by the detection circuit when discharge by the discharge circuit is not executed and a second voltage that is detected by the detection circuit when discharge by the discharge circuit is executed.