Since our successful upgrade of MFD instruments, auto pilot, LPG stove, LED lights, water heater, heads, faucets, windlass, anchor and chain we are now trying to focus on next seasons upgrades. Our boat is presently equipped with a two lead acid house bank (with original charger) and a starter battery. It is really inadequate even for a long weekend of sailing. I have gotten quotes from two different companies for components, but still a lot of questions to answer before we start. On the 40.5 or other Legend series boats, where have people placed most of the components? The starboard lazarette houses the charger and batteries now and would possibly be a good place for a new inverter/charger and PV charge controller(s). Ideas? Planning on four 100Ah batteries...
Lithium Installation for Legend 40.5?
- Thread starter SV Maverick
- Start date
I have 4x210Ah AGMs under the aft berth. Your options are that or the lazarette. If I had lithium I might consider the laz because they're lighter, but I wouldn't want the weight of lead/agm that high.
My inverter charger is 3kw and I installed on the shelf of the aft cabin and made a cabinet for it to reduce noise
My inverter charger is 3kw and I installed on the shelf of the aft cabin and made a cabinet for it to reduce noise
Haven't experienced seas big enough to wash over the cockpit (sailed in gale force winds offshore and didn't get a drop on me), and also experienced intense rains. Never saw leaks in the laz.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 23,065
Haven't experienced is not the same as will never happen. If it does happen with Lithium, are you prepared to abandon the boat?
You are redesigning your boat. Putting a lot of time and energy into it. Choose wisely where to locate your batteries. With Lithium I would choose a safe and dry space that if salt water got to the battery compartment I would likely be stepping of the boat and into a survival dinghy or a rescue helicopter.
But that is just me.
I have four 6-volt FLA batteries in the port lazarette and a 5KW Westerbeke generator in the starboard lazarette. Never had any water in either lazarette. I moved the OEM charger to the wall next to the rudder shaft behind the removable panel. That was a poor choice because the caulking of the wires leading from the console under the cockpit floor aft of the steering console failed and let water into that area. The charger did not appreciate the shower. I now have a new charger mounted to a board underneath the aft cabin berth.
jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 23,065
If there is a way for water to reach electrical parts, I believe water will find the way.
Water and electricity do not mix well, but like a moth to a flame, water is attracted.
Never said it couldn't happen. However, if it did, then it would drain down the hull below the aft berth anyway, so no location we're referencing is safe. The laz is safer from leaking due to it being higher up and having less leaking possibilities. It has one locking latch holding the lid closed. I think either area on this boat could be done with about the same safety margins.
If you're not using the space under the bed, I still like that best due to weight and space distribution.
While you certainly should plan on keeping the batteries dry, I think the reports of EVs immersed in water from Hurricane Ian igniting and reigniting over and over has given a false impression that Lithium Iron Phosphate batteries would react similarly. I assume the OP is only considering LFP. If the LFP is immersed in salt water you are probably just going to lose the BMS. I guess the worst case would be a cell shorting, overheating and venting. In that case just don’t try to ignite the electrolyte vapor, and don’t breathe it of course. There’s no way I would abandon the boat simply because my LFP batteries were immersed. I would probably keep checking their temperature though, and if one started getting hot I’d make it abandon the boat, not me
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jssailem
SBO Weather and Forecasting Forum Jim & John
- Oct 22, 2014
- 23,065
As in all boats such design changes are filled with compromise. One needs to consider all the risks they can imagine and mitigate them.
I read the statement about the OP not having experienced a boarding sea, I am led to assume was during sailing in San Francisco Bay. Just the other day there was a post of an experienced skipper, being lifted out of his cockpit by a breaking wave.
When designing improvements into a boat is is best to choose wisely.
I read the statement about the OP not having experienced a boarding sea, I am led to assume was during sailing in San Francisco Bay. Just the other day there was a post of an experienced skipper, being lifted out of his cockpit by a breaking wave.
When designing improvements into a boat is is best to choose wisely.
This article is a long and detailed read about installing LiFePO4 batteries on a boat.
Drop-In LiFePO4 Batteries – Be an Educated Consumer
Drop-In LiFePO4 Batteries – Be an Educated Consumer
Thanks for the input from everyone. Rich and Baycloud are always helpful, thanks again. On the hard for now. Time to plan. Thinking of keeping the appropriately housed batteries in the lazarette and the electronics inside the boat. My boat does not have the built in shelves (by the foot of the berth) so I could add a cabinet and storage area in the unused space. Would also like to add a headboard.
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Rich
Impressed with the genset install. I was going to put in a FP 4 kw unit, which just would have squeaked in. Ended up with the 49, which was a better plan for me, and never completed the project . (Sold the genset)
Tkx. I installed the genset before the boat ever got splashed by the dealer. The floor was reinforced by a Hunter rep prior to installation. My dealer didn't think it would fit but was fine with my trying. I was pretty sure it would fit, but I was prepared to remove the exhaust manifold if required. It wasn't, and a straight in with a slight tip was all that was needed. I told the dealer that I didn't need that 5# bucket of lard to grease the passage after all!
Funny,, I was concerned that the floor structure would be questionable as originally built.
I would imagine that service is a might tough. But, there’s no ever enough room on boats: no matter how big,
Did you handle switching through a standard rotary switch? Might be complicated if you have 2 AC inputs, but you clearly figured that out.
I favoured the FP solution as it had an integrated sound shield. But, the cost was significantly higher.
btw, my charger inverter was in the aft cabin under the berth above the strut bolts., I fastened it onto the lateral wood panel. Very strong. I think that an airco unit would normally have been there.
Didn’t have airco on the boat. Another reason I bought the 49