PackCfg (0BDh) is the address of a non-volatile register. If MAX17205 is placed with the battery pack (i.e pack side), 0BDh does not need to be written. As the battery will constantly supply power to the MAX17205, the value in the non-volatile register (1B5h) will not get lost. However, if the MAX17205 is placed on the host side, the correct battery configuration needs to be written to 0BDh. This is because the data that is stored in 0BDh will be written into 1B5h after changing the battery and MAX17205 is powered up again. It must be noted that there is a limit to the number of times that the non-volatile register can be written; It can be written up to seven times (page 84 of the datasheet (Rev 2; 8/16))