Whick type of battery is best for inverter use?

[MarioG]

58' Hatteras Yachtfisherman. The boat has a 32 volt system. Currently I have 4 8d batteries per side which are going bad. One side is hooked up to the 3000w Newmar inverter/charger. The inverter/charger is capable of charging AGM, wet cell and gell cell. In my quest to find the best battery for extended inverter use, I would like to know which type of battery mentioned puts out the most Amp hours and is the quickest to recharge. I might make a third battery bank for "house" use if needed/practical. I really would like to go with a battery that is maintance free.

AC power requirments are for general lighting (recessed halogen lighting), 1 refrigerator, 1 freezer, sterio, tv, microwave. I would like to have about 12 hrs of inverter use. The generator will be started twice a day for cooking and charging. Summer time generator use is high due to air conditioning use.

[Pascal]

Best? i dont know... AGMs maybe...
BEST BANG FOR THE BUCK? no doubt... golf cart batteries!

considering how you use the boat (lots of time on the hook, lots of friends and family) I would add a separate inverter bank, keeping the exiting 2nd bank for house and start duties.

Our inverter bank lasts 24 hours, with 880AH at 12v. so at 32v, you should be fine with about 440. Check the specs but i think 8V golf cart batteries should be around 220AH... put 4 together for 32v and 220AH. 2 sets of 4 should get you close to 500AH and last a day. Should cost you around $700 or so, unless the price went thru the rook in the past 2 years..

I get mines for BG Golf Cars...they deliver to the dock! i'll have to look up the number or check on the Exide Florida Website.

[Skip]

It sounds like you have a 32 volt inverter system on your boat. I went with a 12 volt inverter system to leave the 32 volt system for just main engine starting and support of the 32 volt systems (mostly lighting/water pump). I changed over to 12 vacuflush heads vice 32v galleymaid heads. I also changed the upper level lighting overhead lighting to a 12 volt system.

We anchor a lot and the 32 volt systeem will last for many days at anchor. The 12 volt system struggles to make 12 hours because of the inefficient (old) refrigerator.I have about 750 Amp-hours available on the 12 volt system.

The new invertors have really good charging systems that won't boil the water out of the batteries (like the old 32 volt charger). The 12 volt batteries didn't need any water last boating season (I check monthly), but the 32 volt system takes 1 to 1.5 gallons of distilled water every month. I expect to have to replace them every 3-4 years with that water useage, but maybe I will be lucky on longer battery life.

I have noticed that some folks have essentially changed their boat over to 12volts (except for the engine start), and I guess I'm half way there. There are good arguments on both sides of the issue on which way to go. Being able to replace the expensive 32 volts water pump with a 110v water pump from home depot is attractive...

Good luck on whichever way you go.

[bobk]

I have six 6 volt Workaholics on our system which is now 20 months old. Our AC loads sound similar to yours and these easily carry the boat 12 hours. We do have a combiner to allow the alternator to carry the load underway. Don't know if that can be arranged for a 32 volt boat, but Yandina, tech@yandina.com, might be able to help.

Bob

[REBrueckner]

The right way to size your battery bank is to determine the amp hours of use between charges, then get enough batteries to supply three or better yet four times that capacity.

See my 12/2005 post "DC System Design". Charging rates for different batteries are given in that post:AGM's charge four times faster than wet cell lead acid.

[SKYCHENEY]

Mario,
You wrote that you have 4 8D's per side. Are you sure they are not 8v195's? 8D's are large 12v batteries. The 8v195's are long 8v batteries that fit in the the OEM boxes, 2 per box to make up 4 per side in series or 32v.

I will assume you mean 8v batts. In that case, you will have a hard time finding AGM's or gell cells. I think your best bet will be a good deep cycle battery, meaning one with the heaviest lead plates you can find. Most likely this will lead you to Rolls/Surrettes. Send a PM to JCRLAW. He just installed the Rolls on his 58YF over at Marco Island. I looked at his install a couple of months ago and the batteries fit in the boxes perfectly. He runs his 32v Outback Inverter off of them.

[MarioG]

Sky, you may be right. My batteries are as you describe. I guess they are 8v. Pascal has a nice setup on his boat and he has offered to help figure mine out. I may end up with a system similar to Pascals. If only I can find AGMs that would fit the bill. another question that is raised is do I have enough alternator output for this size and type of batteries? If I do make a seperate bank for inverter, is generator or shore power the only way to charge the third bank?

Yes, I'm all thumbs when it comes to anything electrical!

[SKYCHENEY]

Mario,
Why complicate the system with more batteries? Just use the house bank to run the inverter. I have a 3300watt Outback inverter hooked to my house bank and it works great. You don't need extra batteries. You don't need different voltages and you don't need anything other than the original lead acid 8v batts.

MikeP is set up that way. Mine is set up that way. Jcrlaw's 58YF is set up that way. We all run our inverters overnight without a problem. If you want more info, call or PM myself or Mike or John (Jcrlaw). It's the most simple solution and it's the cheapest.

[thoward]

I have 4 Trojan GC 8v batteries I would be willing willing to sell right. They were used for about 2 weeks and have been parked in storage for about a year. $200....

[MarioG]

Mario,
Why complicate the system with more batteries? Just use the house bank to run the inverter. I have a 3300watt Outback inverter hooked to my house bank and it works great. You don't need extra batteries. You don't need different voltages and you don't need anything other than the original lead acid 8v batts.

MikeP is set up that way. Mine is set up that way. Jcrlaw's 58YF is set up that way. We all run our inverters overnight without a problem. If you want more info, call or PM myself or Mike or John (Jcrlaw). It's the most simple solution and it's the cheapest.

LOL, I guess I'm over engineering this! Maybe as soon as I put in new batteries I'll have better performance from my inverter use. The reason why I wanted to go with a agm or gell was strictly for ease of maintance.