Controller Card, Battery Health, Failed

We have 10 B1200i devices and 8 of them show:
Controller Card / Battery Health / Failed
What is the procedure for replacing the batteries?
What is the purpose of a battery on the iSCIS card?
Would the failed battery be the root cause of my DROBO B1200i losing connection to the network?

hi tadpole, on other drobos i believe there is an internal, self-recharching on-board battery to help against power cuts… maybe the b1200i’s also have one on the iscsi card as an extra failsafe?

there was another user who mentioned replacing a couple of bad controller cards before, and that it solved their connnection issues… am not sure exactly what the battery is for, and it may just be a large button battery like some motherboards on computer, though probably best to contact support to double check, in case it needs or uses something specifically?