Battery charging advice needed

[Rattone]

Sent: 7/29/2003

I have a 1977 23ft Minnie Winnie with a Kohler 3.5Kw generator and one 12v Marine battery.  I hate having to run the generator for everything and was thinking about installing an Inverter.  My aux battery gets a trickle charge when driving vehicle and switch set to aux.  I can also charge aux when hooked up to AC and when generator (I believe it is only a trickle charge) is running.  Any suggestions on type of inverter and what else I should get with this?  I hear that running the engine 10 minutes every hour will charge aux battery. I do not plan to run air conditioner with inverter, just TV, dvd, satellite, microwave, water pump, etc.

[Rattone]

   
I have been doing a little research and I read that replacing my marine battery with a deep cell battery will increase your time on the battery.  Is there any considerations in going from a marine to deep cell?

[jbrt1989]

 
If you are really serious about using a lot of energy while boondocking..or not hooked to any services.. I would suggest looking into a solar solution.  We have a thread dedicated to that subject and some have had a lot of success.  It may be out of range of many budgets, but, it is a very worthwhile investment if one is planning on spending a considerable time needing power without the hookups and over use of the genset.

I know it's possible to run off batteries like you need, but, I also know there is a trick to getting it right.  I'm certain someone here knows that answer better than I.  I have yet to get more than a night out of my two deep cycle batteries running just a few lights, perhaps a fan or heater blower, and the dish TV for a few hours before going to bed.

[Boat Nut]

If the battery you have is Marine, it probably is a "Deep Cycle". Having Deep cycle batteries just means that, running them down doesn't kill them so fast. If your battery is 3 years old and it runs down to fast, replace it. Having more batteries can be a good thing. But it is no free lunch. Only experience will tell you what works for you.

I would say try a new size #27 or #31 deep cycle. If you still don't get enough time, add a second in parallel. (that is + to +, & - to -). Or you could just go ahead now and buy 2 golf cart (6 volt) batteries and install them in series to get 12 volts. That is actually the best setup. If you want to go hi-tech, I understand the solar panels are great, to recharge.

[Rattone]

   
I am trying to avoid solar if possible.  The most I will be out is usually on weekends only.  If we go on a long trip we will make sure there are RV parks on the route.  Chuck, the battery I have now is a marine with 650 cca and is 3 years old and goes down within the day using pump and lights.  I can keep going for the weekend if I run the generator for showers and doing dishes.  My gen is a Kohler 3.5kw and is pretty loud compared to other gens I hear when camping.  I am going to get a portable to use for TV, pump so I can run at night without complaints.  But getting back to the batteries, are you saying that two 6v running in series is better than one 12v battery?  I looked at a company called lifeline or something that their 6v battery (deep cycle) had over 400 reserve hours. i assume that would mean double the reserve with two of them.  That is alot of minutes to run things.

[Boat Nut]

Perhaps you would enjoy this site http://bart.ccis.com/home/mnemeth/12volt/12volt.htm
It has a world of information on 12V systems.
A new #27 battery should give you a weekend of lights and pumps, mine always has.
I buy my batteries @ Costco. Also Sams Club has good prices, or Walmart.

[mightybooboo]

 
If you are recharging with the generator, through your converter,that is a bad solution.The amps most converters send out is very limited and it takes all day to get a charge,and even then its never a full charge.Get at minimum a stand alone charger that plugs into the ac,and use it to charge batteries,or change out your converter with one that offers 3 stage charging,a ton more efficient.A battery starting out with less than a full charge will not get you far, I'm thinking your battery is still undercharged.And any portable genny with the 12 volt outlet,it really isn't for charging,its for using 12 volt goodies directly off the genny,at least as far as ive read.You need a stand alone auto charger,or a truecharge,or a progressive dynamics type converter with a charge wizard.

[mightybooboo]

   
Re solar,you can get 150 watts of panels,a charge controller,and mounting,wiring for a thousand bucks.For a weekend warrior you would always start with fully charged batteries and in good sun be recharged by afternoon if you do a few lights,little TV,and heater blower.For 350 less you could cut the panels to 75 watt,and still get you through the weekend,leaving from home again with an always fully charged battery.
When you get the genny,please get the quietest you can afford,your neighbors will really appreciate it,and lots of places are really getting testy about noise nowadays.I have a 79 winnie minnie and would bet its the same genny,that puppy is loud and hasn't made me any friends using it.I use it as little as possible.

[Collyn down-under]

A marine battery is a compromise between a deep cycle and a starter battery. Generally speaking a deep cycle battery is more satisfactory for RV house use but there is one exception. A deep cycle battery does not like being discharged at a higher rate than 25% of its ampere/hour capacity, A microwave oven fed via an inverter may draw 130 or more amps - hence if a microwave is used a lot you either need about 500 amp/hours - or you are probably better off using marine batteries.

The arguments re two big six volt batteries in series or two smaller 12 volt batteries in parallel is substantially theoretical. My own choice is to parallel two smaller 12 vots - it's a different matter with large battery banks, but at RV level do whatever seems more convenient.

Listen to what boo boo is saying re three-step charging. It's the ONLY really good way.

[Rattone]

Re BooBoo's reply on charging... Can I just hook up a three stage charger to an ac outlet being powered by inverter and connect to the deep cycle battery and always be charging therefore never loose battery strength to run appliances?  I was thinking about getting an 2000 watt inverter and one or two deep cycle batteries and a standard 50 or 60 amp three stage charger.  Do you think that would be adequate to power TV w/ dvd, sat dish, water pump, coffee maker or occasionally microwave for a few minutes?  I am just looking to get by for the weekends without having to run generator at campgrounds.  I will eventually buy a Honda eu2000 to replace built in Kohler 3.5KW that is very noisy.  I can run everything on that except roof A/C.

[Cooneytoones]

Sent: 10/15/2006

With winter approaching batteries are on our mind, this article will help you get you battery through the winter....and help extend the life of your battery.

koa.com/updates/2006october/RV101.htm

Timmy