Battery bank addition

[tonyiiiafl]

As we have spoken, I have a start, genset battery and a pair of T105 6V GC batteries for the house. Not running a lot, but would like a bit more capacity. We run genset a couple times a day for 2 hours. House bank usually around 80% in the AM and 85% end of day. Genset brings it back to 90-95%. I am looking into solar panels also.

Anyway, not too much room on my ‘94 390CPMY. I was thinking of placing the 2 additional 6V GC batteries in an appropriate battery box and placing them forward in the galley area under the floor hatch. I could make a bracket from pro to starboard and put a shelf for the box to rest. Then run the heaviest cables I can get to join them to the other set of house bank that is between the engine. Should I be concerned about the off gassing? Seems like we have some ventilation down there. Here is where I am planning on placing them. OR I could relocate the shower pump 90 degrees to the left and place the batteries to the right of it. I think it close enough to the center line to to make much, if any lean.

Ignore the water in the bilge, as I put bilge cleaner in there and turned on the hose. I will get it up on plane on my return trip to have the center bilge pump remove it.

B21A94EA-2252-412B-A3F4-8B3EFCB856E3.jpeg

[Midnightsun]

How old are your GC batteries you have now? I say this because it is not a good idea to mix old batteries with new.

If you have no room and the batteries are older, a set of L16's are the ticket as they fit into the same footprint as 2 6v however they are much taller. 2 of these are equivalent to 4 regular GC batteries although they do weight quite a bit more at 115lbs each. This would use the existing wiring so not much to do to replace the existing setup. Only issue is they are rather spendy. https://www.solar-electric.com/trl16vo225ah.html

By the way, this is what I have now.

[tonyiiiafl]

My present batteries are in their 3rd season. I like the idea of those, but not sure they will fit height wise between the engines. They are 5.5” higher than what I have now. However, I never say “NO” unless I get in there and scope things out. I am not against taking the floor board that is over the battery storage area and modifying it. HEAVY for sure! I would need help in moving those suckers! Cost? Not scaring me as to the value, and not having to redesign the other set for storage forward, and having TWO more batteries to check.

Thank you and more when we get back from our trip. Been gone for 5 days, and heading back to the Cape tomorrow. Been super weather!

6E347069-AAB1-4CDB-8561-AC21A0EF803F.jpeg

7DF97644-3682-42FC-BF9D-862BE8C90F3B.jpeg

7CE4C852-71AF-4A42-97B6-11184B796AFD.jpeg

B723866B-A825-4208-85E4-9F8605180B5F.jpeg

[tonyiiiafl]

Qr Bbpost My present batteries are in their 3rd season. I like the idea of those, but not sure they will fit height wise between the engines. They are 5.5” higher than what I have now. However, I never say “NO” unless I get in there and scope things out. I am not against taking the floor board that is over the battery storage area and modifying it. HEAVY for sure! I would need help in moving those suckers! Cost? Not scaring me as to the value, and not having to redesign the other set for storage forward, and having TWO more batteries to check.

Thank you and more when we get back from our trip. Been gone for 5 days, and heading back to the Cape tomorrow. Been super weather!

6E347069-AAB1-4CDB-8561-AC21A0EF803F.jpeg

7DF97644-3682-42FC-BF9D-862BE8C90F3B.jpeg

7CE4C852-71AF-4A42-97B6-11184B796AFD.jpeg

B723866B-A825-4208-85E4-9F8605180B5F.jpeg

[tonyiiiafl]

Actually, I was thinking I could lay a 2 x 3 on top of the stringer that the battery cover plywood rests upon and raise it just enough to accommodate those larger batteries. I would get a friend to help lower them into place. YES! I love that Idea Hans, so much easier! Thank you!

[bud37]

Qr Bbpost Should I be concerned about the off gassing?

That should always be a consideration especially as the battery banks start to contain more batteries.....offgas Hydrogen is light and will rise, so some way for ventilation/ escape would be good, avoid trapping it as it is explosive.

I ran a vent line from my battery box top to the exhaust side of one of the bilge blower lines out. That will passively vent the light fumes with out blower intervention as it is up all the way out.

[vineyardgray]

You might consider instead swapping out your existing batteries with Firefly batteries - no sulfation issues, you can run them in a partial state of charge much more frequently without ill effects, accept a high rate of charge and can be used below 50% state of charge so your usable Amp Hours are doubled.

They also make L16's which are much taller as Hans describes but they are 4v so you would need three to get to your 12v (this is the system I am using).

[g36]

looks like a nice place to boat