We're restoring / upgrading a high-mileage 2011 SMB Sprinter 2500 RB110S, and I've just replaced the two ancient house batteries with two high-end 105 Ah Duracell Ultra Platinum AGM Deep Cycle Batteries. The AGM chassis battery is reportedly fairly new but I haven't pried it out to see what the brand, model and date of manufacture is (nothing visible on top).
The electrics seem to be all original, and the (old style) Zamp 30amp solar charge controller and Tripp-Lite inverter systems seem to handle the AGM batteries just fine, but offer no monitoring of battery SOC.
Is the Victron Energy BMV-712 Battery Monitor with Battery Balancer Bundle the best deal for accurate monitoring of all three batteries? I'm assuming that it comes with two shunts, or that additional shunts can be ordered?
I'm not interested in completely replacing all the electrics, inverter, controls, etc -- I'd like to keep costs under control, and will be sticking with AGM batteries for the next 3 years at least. I might replace the Zamp with the newer model 30amp solar controller, but if I don't need to I'd prefer to wait.