Comparing battery types

[dhays]

"AGM is a great battery and the cost has become reasonable."

Not sure they're this reasonable - In the middle of buying 8 Trojan 6 volt T145's (260 Ah @ 20hr rate) for $180 each. Shipping isn't final but should be between $100-200.
Looked at Carbon Foam and like what I've found so far but they'll probably be the replacements for these Trojans. Also about to pull the trigger on a Victron Multiplus 3000W


Edit- Also springing for two watering kits at $91each so there's that cost to add to it.

They have a great reputation and with a watering system should be easy to maintain. In your shoes, I'd probably spent 1/2 the money and go with Costco or Sam's club GC batteries and sacrifice some Ah. I think they are typically about 210 Ah each instead of the 260 Ah of the Trojan.

 

[Boatfever]

Thought about going with similar; NAPA GC2 8146 like I'm replacing but I want to get the most Ah that can fit into existing batt boxes at reasonable cost. If and when I go Carbon Foam, I'm thinking of the 450Ah 4 volt units times six for 900 Ah total but with more DOD resilience. Those would likely go under the floor of the forward cabin. That's the mental picture at the moment anyway. The Victron Multiplus into a port side cabinet to keep out of the 120F engine room.

 

[dhays]

Thought about going with similar; NAPA GC2 8146 like I'm replacing but I want to get the most Ah that can fit into existing batt boxes at reasonable cost.

Makes perfect sense and the Trojans have a reputation for long life and good performance.

 

[foggysail]

First--- yes, chinese batteries of any type are most likely less expensive than quality batteries manufactured here. But wait to see how popular they remain if Trump slaps a 25% tariff on them. In the mean time I intend to stick with popular flooded golf carts made in this country.

Next, I finally got around to checking the fluids in my 11 batteries, 1 is dedicated to my genny, another 2 connected for 24v for my windlass and the remaining 8 form 2 banks for house/starting. I was very impressed with how little distilled water they required. I attribute this to my Victron 150-70 controller. This controller matched to my 4 each 295W solar panels allows me to spend as much time on anchor as I desire without needing to run our genny.....we do run it for both hot water and making coffee in the mornings when away from our slip.

 

[Art]

My $1.00's Worth!

Last Sat, 10/6/18: I changed our nearly 9 yr. old 4 batt battery bank [deep cycle 31M la wets] with exact same model new 4 batts. Cost of batts proper [$440 dollars in very early 2010] averaged out right at one dollar [$1.00] per every week for the entire duration of nearly 9 years. That's a cost I can live with and am pleased to announce! The new four similar batts were still under $500. I'm anticipating to experience approx $1 +/- per week house bank batt cost for the next 9 yrs!

I get all battery needs from local franchise of "Batteries Plus Bulbs". U.S. based - East Penn is the battery manufacturer.

I believe it is correct to appraise of these facts: Living 100 miles separated from marina in CA Delta, we only find time to use boat an average of 8 to 10 fairly-long-weekends per year. And, we do not very often spend more time at dock than what's required to on-load/off-load. We do spend much time at anchor swimming and playing/relaxing as well as running around in our tow-behind, quick and comfortable Crestliner o/b runabout. Additionally, I never leave boat plugged into shore power when we leave boat for any length of time. Also, our boat is rigged with mostly AC apparatus [stove, oven, fridge, microwave etc] that runs off gen set or shore power... so batt inverter is not required. In other words... our house bank power supply is not too often over taxed! As an aside - I don't let house bank drop below 50% charge before bringing it up to full charge again and I always keep batt distilled water level in correct position [usually check and add a little distilled once per year}.

In addition to house bank I also have specialized 24 starter batt for gen set and an isolated 'black box" 24 starter batt kept as emergency assist if needed [I like safety-redundancy aboard boat]. The emergency batt stays fairly new and fresh by getting cycled into gen set batt and/or runabout batt as may be required. These batts are both kept at 100% charge via AC trickle chargers and for the genset also hooked up is a small solar panel on fly bridge front.

BTW - Both engines start off the 4 paralleled 31M house bank batts. Starboard engine has big amp alternator that also charges house bank.

Soooo with no more explanation... I'll post photo of old batt bank just replaced. Then, new batt bank installed last Saturday. Then, emergency "black box" batt and gen set batt smart trickle chargers. Then 1977 60 amp very dumb "Professional Mariner" batt charger [still works well]. Then, very smart NOCO genius GEN 4 - 4 bank, 40 Amp 2018 charger [plan to install next visit to boat!]. https://no.co/gen4

There - That's my $1.00's Worth