R-21EC Battery Replacement

[Sheepdog012]

Hi All, I'ts time to change out the batteries in my 2015 R-21 and I'm trying to decide between AGM or lithium. I would like to increase my house battery to 100AH because I like to stay on the hook and would like to be able to run the fridge, a fan and anchor lights overnight as well as some charging of electronics. I bought the boat last year and the previous owner tells me this coming season would be season 4 on these batteries, which I believe are Interstate flooded marine/RV Group 24 either 64 or 75 AH. Would anyone have any insights on AGM vs Lithium? I have a pronautic 1220P charger and the stock 115 amp alternator on the Volvo D1-30. I believe the charger has a lithium profile, but am wondering about the alternator? Any insights are appreciated!

 

[MarcoArias]

Hi!

AGM would be the easiest installation, by far. The most important change would be changing the settings on the relevant electrical components (e.g. charger, inverter, etc.)

Lithium would require not only the change in settings, but also isolating the lithium bank (house). This can be done through rewiring in a network of VSRs (ACRs) and a DC-DC charger. You would also need a battery monitor for the system; a shunt would need to be installed. Volvo does not recommend having a lithium battery for the engine at this time. Lithium battery charging characteristics can lead to bad alternators if proper wiring is not done. Feel free to email me if you decide to go this route.

Thanks!