Stupied house battery question

[rlamb]

On my 2005 Hunter 466 it came with 3 Lifeline 2D AGM house batteries. While I dont know for sure I suspect they are all the same age. I have them all on the House #1 switch. I just bought a new Lifeline 2D AGM battery and since I read you shouldnt connect older and new batteries I was planning on putting it on the House #2 switch. Given that I wondered if there was an issue if I switvh the House banks to "ALL".

Thoughts & Comments?

 

[Don S/V ILLusion]

The theoretical problem arises when you combine the old and new batteries under charge. The charger can't differentiate between old/new or varying degrees of capacity so it sees the lowest common denominator, that being the battery(ies) requiring a high(er) charge rate than the new battery thereby potentially overcharging and cooking the new one.


This can happen when combined at the switch as well as effectively combined when charging via an ecocharger, charging relay or isolator.

 

[TFU]

Best solution is to change to the newer generation charges that can charge up to 3 or more battery banks. Connect it directly to the different banks (ie. new and older batteries separated into banks but combined for load). The older batteries will not last as long to get to recommended 50% discharge level but the charger will charge each bank at their appropriate needed rates.