I;m changing my house battery system

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2savage

Senior Member
Joined
Feb 21, 2017
Messages
278
Location
USA
Vessel Name
Savage
Vessel Make
Seaton 50 expedition trawler
Currently I have six 6V Trojan L16-ac old school lead acid batteries and they are old and showing signs of decay. Worse than that they now will not power up the inverter consistently so I fear they are shot.

I'm transitioning to four deep cycle 12V Gel batteries from Renology, each rated at 200ah. They are supposed to last around 15 years and come with a three year warranty.

Finally I'll be swapping out a bunch of old battery cables that may be CCA (copper coated aluminum) with all copper marine cables with s gauge of 0/1.

Does this sound like a decent power source for house batteries?

I do have twelve solar panels plus three 8D batteries for main engine and generator starts.
 
Catch-22 here. You are replacing 1125 amp hours with 800 amp hours however considering the condition of your L16’s you are certainly going to feel like you have more amp hours.

With out knowing charger specifications, inverter specifications or run length of wire I really can’t comment on the rest.

Since you haven’t increased any capacity then staying with the same wire size should be fine. However, I have no way of knowing if things were done right the first time.
 
Were it me... believe I'd replace flooded L16s with Lifeline L16 AGMs, same number as what you've got.

Partly to reduce maintenance, partly to reduce off-gassing.

Or I'd replace with flooded L16s, if service might be easy and if location is semi-immune from affects of off-gassing.

Would not use Renogy, simply because they have a really horrible reputation for customer service. See various posts, including some from Rod Collins (CMS).

-Chris
 
One thing I just read this weekend is that you do not set these up in parallel for more capacity. Buy a bigger single battery.
 
I'm guessing there is a reason you aren't switching to LFP? I expect the gel batteries are not a lot less expensive, but not sure.
 
https://www.mobile-solarpower.com/lithium-batteries.html

Power Urus LifePo4 $400 for 100AH of which you can actually use 80AH without damaging batteries (conservative estimate) 3500 cycles

Renology Gel $208 for 100AH of which you can use 50AH without damaging batteries 750 cycles.

So, if you need 800 actual Amp Hours that is a Capital Investment of:

$4000 for LifePo4
$3328 for Gel

Lets say you cycle them once per night cruising so the price per night is:

$1.14 For lifePo4
$4.44 For Gel

The Gel Battery is almost 4x the price of the Lifepo

The gel battery also requires you charge it considerably slower so when using a genset or engines to charge them you will burn considerably more fuel and wear on genset doing so.

Put up urus as an example.
 
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One thing I just read this weekend is that you do not set these up in parallel for more capacity. Buy a bigger single battery.

Ignore this. I was thinking LiFePo4.
 
Currently I have six 6V Trojan L16-ac old school lead acid batteries and they are old and showing signs of decay. Worse than that they now will not power up the inverter consistently so I fear they are shot.

I'm transitioning to four deep cycle 12V Gel batteries from Renology, each rated at 200ah. They are supposed to last around 15 years and come with a three year warranty.

Finally I'll be swapping out a bunch of old battery cables that may be CCA (copper coated aluminum) with all copper marine cables with s gauge of 0/1.
.

Unless you have ventilation issues, I’d swap out the Trojan L16’s for East Penn/Deka L16’s. Scrubber batteries are dependable, widely available & less expensive since they aren’t “marine”. Add a watering system for $100 and upgrade your cables as1/0 seems a bit light depending on your inverter loads. Good for 7-10 yrs.

As others have mentioned, battery replacement may be very dependent on your chargers, ideally, per Rod Collins (Marinehowto.com) you should customize the charging profile to the battery manufacturers recommended specs. If 1 charger supplies different banks, best practice is that the battery charging specs be the same. For instance:East Penn charging specs are the same for all sizes of their FLA batteries but their specs are different than Trojan FLA’s. Similarly, AGM, Gel & FLA usually have significantly different charging parameters.
 
As far as L16s go, I've had a pair of Fullriver L16 AGMs in my boat for a few years. We're on season #3 with them so far and they're still performing exactly as expected with no noticeable degradation yet.
 
I have been LFP (the cheap $300/100ah ones) for over 6 months of full time on the boat. I used to be a naysayer of lithium, but now I would never except in an emergency get a lead acid/AGM/Gel battery for my house bank.
 
So...As long as you are a millionaire I would also replace those darn 8d's they don't belong on a boat, no matter how big the boat is. They are too heavy as you will learn when you try to haul them out, unless you have a crew.

pete
 
So...As long as you are a millionaire I would also replace those darn 8d's they don't belong on a boat, no matter how big the boat is. They are too heavy as you will learn when you try to haul them out, unless you have a crew.

pete

The install was done by myself and a 79 year old guy in 6 foot seas after transferring them from a Tow Boat US. And total boat weight is 106,000 lbs. So, handling them is doable and the extra 80 lbs or so is negligible. The 8D's are 18 months old and work just fine.
 
The install was done by myself and a 79 year old guy in 6 foot seas after transferring them from a Tow Boat US. And total boat weight is 106,000 lbs. So, handling them is doable and the extra 80 lbs or so is negligible. The 8D's are 18 months old and work just fine.

was the 79 year old swedish? Just reminded me working along an old guy in my teens trying to keep up.
 
My friend just replaced the 28v gel battery in his airplane (where it makes some sense to have a gel) $600 for one. The original only lasted 14months. Had his alternator/regulator checked first, it was fine.
Question: Why would you replace a proven system, that has served you well, and that may only have one bad battery (or even one bad cell) and that may require changes to you charging system, with the "latest & greatest"?
 
So...As long as you are a millionaire I would also replace those darn 8d's they don't belong on a boat, no matter how big the boat is. They are too heavy as you will learn when you try to haul them out, unless you have a crew.

pete


We still have over 2000lbs of dead lead batteries on board
Weight is good for us, could go with about about 4000lb more.

But Lifepo4 is so much better for us use wise and considerably more affordable
 
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We still have over 2000lbs of dead lead batteries on board
Weight is good for us, could go with about about 4000lb more.

On your boat, the weight is a non-issue. For many of us, 2000 extra pounds would be a significant negative in how the boat behaves, fuel consumption, etc.
 
On your boat, the weight is a non-issue. For many of us, 2000 extra pounds would be a significant negative in how the boat behaves, fuel consumption, etc.

I realise that
It was a response to the "8d's they don't belong on a boat, no matter how big the boat is" line
 
I realise that
It was a response to the "8d's they don't belong on a boat, no matter how big the boat is" line

The issue with 8Ds isn't the total weight of a battery bank, it's the combo of their weight and shape making them very hard to get in and out of the boat in many cases. Something like 6v golf carts or L16s are individually a bit lighter, and their proportions also makes them easier to lift with 1 person.
 
The issue with 8Ds isn't the total weight of a battery bank, it's the combo of their weight and shape making them very hard to get in and out of the boat in many cases. Something like 6v golf carts or L16s are individually a bit lighter, and their proportions also makes them easier to lift with 1 person.


Yes, issues, but that still doesn't mean a blanket statement like 8Ds "don't belong on a boat..." is correct.

Don't belong on some boats, maybe. Other battery sizes can often be more manageable, maybe. Et cetera.

I have to admit, I don't do all that well with dogmatic blanket statements about much of anything. And I'm one of the folks who usually thinks "it depends" can often be a legitimate response.

-Chris
 
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My experience with a brand new renology inverter was awful. It would jump to fault when running a floor fan. I was using new batteries and never could get it to work properly. Then I got involved with their company rep who wouldnt stop talking and gave bad advise, as in its basically my problem to solve. Solved the issue it by returning it to Amazon and buying a different brand which works just fine with my setup. Stay far away from this company's products, very far away.
 
Savage
You mentioned a potential inverter problem in your first post. Assuming it is a charger combo I suggest you look at your overall system.

Scott on slowgoesit has a marvelous description and writeup of what he’s done in his transition to LFPs. If you’re not a heavy duty away from the dock cruiser your needs may be simpler than Scott’s.

Think it through and don’t jump too fast, especially with the wrong vendors.

BTW, our 8Ds for starting work just fine thus the “no place on a boat” dock talk is ignored and happily so.
 
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My experience with a brand new renology inverter was awful. It would jump to fault when running a floor fan. I was using new batteries and never could get it to work properly. Then I got involved with their company rep who wouldnt stop talking and gave bad advise, as in its basically my problem to solve. Solved the issue it by returning it to Amazon and buying a different brand which works just fine with my setup. Stay far away from this company's products, very far away.

Same here. 2-years ago I bought a Renogy inverter for my camper van. I was at my cabin in Colorado, 8500 foot elevation. Ambient temperatures in the 60's F. Inverter kept throwing an over-temp error. Renogy tech support took days to get a hold of and would only respond via email, with several days between responses. Ultimately Renogy Tech Support diagnosed the problem as a dead battery bank despite screenshots showing 12.8v. I had to file CC complaints and BBB complaints to get them to RMA the inverter. And then I had to chase them for 3-months to get my money back.

Stunningly bad experience.

Peter
 
Avoid Renogy batteries. 3 year warranty is worthless. Take a look at going with Kilovault or Epoch lithium. Both Rod Collins and Pando speak highly of them. Epoch is announcing a 400Ahr any day now.
 
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