for optimal performance of the system through mode data transfer is used for sending command messages from the battery manager 111 to the liics devices 101 while shift mode data transfer is used to receive at the battery manager 111 all the confirmation messages with status and measurement values sent by the liics devices 101 fig4 shows for an embodiment the data flow in the system over time int 0 int 6 represent timing intervals during which data is transferred between the depicted devices a data transmission cycle commences when at time interval int 0 host 411 initiates a write broadcast command 439 sending data to the liics device 401 a nearest to the host 411 preferably using through mode communication while the liics device 401 a is receiving the commands it immediately forwards the command to the liics device 401 b which in turn immediately forwards the command to the next device that broadcast command 439 as it propagates will be interpreted by one or more liics devices 401 all of the liics devices 401 reply to the host 411 with their confirmation message most likely in shift mode while five liics devices 401 a e are depicted this is only illustrative and it will be appreciated that more or fewer liics devices could be provided in further detail the broadcast command 439 is shown as a line having a series of slanted upward pointing arrows the lowest arrow in the int.