In just one location, I have a DSC PC4020 panel (that has two lead acid batteries), which is integrated with a PC4820 access control (another 2 batteries) and the COMBUS travels via an underground conduit to another building on the same system so there is a DSC PC4204 Power Supply/Combus Repeater Module with yet another two batteries.
I really getting tired of buying battery technology from the 1800s every year or two so I'd like to replace them all with LiFePO4 which should last 10 - 15 years. The caveat is of course that the trickle charger in these panels is designed to maintain lead acid batteries and not the right characteristics to provide maintenance for LiFePO4 batteries but one