bq76940 current accuracy

There are essentially 2 current accuracies to consider, one for the CC and the other for the protection limits.  Both depend on the sense resistor and its connection.  The value of the sense resistor of course will determine the basic scaling from current to voltage, the IC responds to voltage and the datasheet specifications are related to voltage.  The sense voltage to the IC is I x Rsense. Beyond the basic value however, be sure to consider the tolerance of the resistor and its temperature coefficient.  On the board, consider how the connections are made and if any of the board trace makes up part of the effective sense resistor.  If using a 2 terminal sense resistor, the solder connections will be part of the sense resistor.  If using a 4 terminal resistor the solder should have little effect.  Losses in the filter components should be small enough to be neglected.  Depending on grounding, common mode voltage to the sense pins may have some small effect.  The system can calibrate the current measurement, the protection limit is fixed in the part once the register value is set by the system.

In the datasheet, CC accuracy is in the "16-BIT CC FOR PACK CURRENT MEASUREMENT" section page 15, see CCINL, CCOFFSET, CCGAIN, and CCGAINDRIFT.  The current protection threshold tolerances are in the bottom of the "INTEGRATED HARDWARE PROTECTIONS" section page 16, see OCOFFSET and  OCSCALEERR.