Please critique decision on batteries and charging

[mrad]

First off, I want to thank all that have offered advice on how I should have the battery system set up on the new to us toy hauler we will be picking up on Wednesday. The biggest downfall I have with it is the residential fridge. I had asked questions about charging batteries with a 2200 Ryobi as well as if I should put two group 31 in it. The 31's are out as the dealer cannot get a vented case for them and even if he could, this forum has convinced me to go the golf cart battery route. At this time I hope to go with at least two golf cart batteries and if room allows, have them hook up four. From what I understand, the two golf cart batteries should give me more amp hours than two group 27's???

Is there a big difference in brand quality on golf cart batteries? Or all they all better than 12 volt deep cycles?

I had also asked about charging in the event that we dry camp once a year for 3-4 days. The hauler has a 5500 watt onan, with a Xantrex pro xm1000. If I were to start the onan up, how long would it take to fully charge two and or 4 golf cart batteries?

Once they are fuly charged, would the 2200 be able to supply enough power to keep fridge and batteries charged for the day?

I also have a champion 3100 I could use and may to keep one ac running during the day and then fire the onan up later in the afternoon so both can keep it cool for sleeping.

Again, thanks for all the help.

[Gdetrailer]

Yes one pair of GC2 golf cart batteries WILL give you more Ahr capacity than two group 27.

Group 27 will give you at best 80Ahr each so a pair of group 27 gives you max of 160 Ahr. However, that 80Ahr is if you ran them 100% flat.. Which will kill the capacity in a matter of a couple cycles. Basically, you would only want to take a max of 20% out of group 27 and with two that means you get 32Ahr to work with.

The lowest rated GC2s would be 210Ahr and with GC2s you can easily extract 50% of the capacity and not harm the battery so you could easily use 105 Ahr.. GC2s can also be drawn even lower than 50%, you can extract up to 80% which is what the manufacturers use to rate the amount of charge/discharge cycles at..

Don't do that to group 27s..

And yes, I use one pair of GC2s to power my home fridge conversion, I have no issue going 24 hrs without the need of recharging. Add some solar panels and I could easily make a long weekend without the need to run a gen.

[mrad]

time2roll wrote:
When the battery hits 14.2-14.4 volts continue one more hour. Amps will be tapering off and it gets to be a trickle charge soon enough. This is probably a 2 to 4 hour charging period. Often people run the generator when preparing a meal so the microwave and other appliances can be run at the same time. Watch the quiet hours as you don't want to start a 2+ hour charge 20 minutes before shut off. You will find a rhythm that works for you soon enough.

Costco GC2 work great for me. RV should come with at lease 2 house batteries with a residential fridge. I would ride them hard and use them up before you spend money.

I would tend to just use the Onan. It needs the exercise.

They are giving me credit toward the GC batteries. They were gong to give me two new grop 24's

[wa8yxm]

A pair of GC-2 Golf Car batteries should be around 220 AH at the 20 hour rate (Give or take about 10)
The proper charge rate is about 66 (or less) so a Progressive Dynamics 9260 (or equal) would be my choice

A 1000 model INVERTER generator **SHOULD** power one of those but you are right at the limit of it's rating.. My old Generac 1000 (A 1000 watt Traditional generator that really could crank out 1000 watts).. Had no problem with a 9180+wizard.

Another factor is depth of discharge

IF the batteries are say.. ONly down 25 perent.. They likely will NOT draw the full 60 amps so the 1000 will be right happy.

[time2roll]

When the battery hits 14.2-14.4 volts continue one more hour. Amps will be tapering off and it gets to be a trickle charge soon enough. This is probably a 2 to 4 hour charging period. Often people run the generator when preparing a meal so the microwave and other appliances can be run at the same time. Watch the quiet hours as you don't want to start a 2+ hour charge 20 minutes before shut off. You will find a rhythm that works for you soon enough.

Costco GC2 work great for me. RV should come with at lease 2 house batteries with a residential fridge. I would ride them hard and use them up before you spend money.

I would tend to just use the Onan. It needs the exercise.

[Lwiddis]

“If I were to start the onan up, how long would it take to fully charge two and or 4 golf cart batteries?”

With the Onan running it is not an issue of enough power, and that should go for the Ryobi too. Bulk charging goes quickly but the absorption phase is slow...could be two-three hours plus. In absorption the batteries slowly accept less and less. This is battery basics.

[BFL13]

You want the higher AH 6s. Eg Trojan makes a 210 and a 225. Choose the higher AH option.

Not sure of qualities. it is more about taking proper care of them. I am very happy with my 230AH East Penn GC15s, but there are many other choices.

You do not fully recharge batteries while away on generator. You run them down to about 50% and then recharge to 80% or so (called "50-80s") it takes too long to get them to a higher SOC on gen time. Wait till you have shore power to get them to full.

If you have solar you can get them to a higher SOC before dark. In that case, do your 50-80 in the morning and let the solar do what it can the rest of the day. (you can run the solar while doing your gen/charger to get more amps--just leave the solar on all day--it will do whatever it can.

The time to recharge two or four 6s from 50% depends on your charging amps and whether you do a 50-80 or a 50-90. The 80-90 part will take an extra hour of gen time for not that much gain. Think of three hours of gen time for a 50-80 on two 6s with a 55 amp charger, eg.

You need enough generator to run a charger at higher amps. two 6s can take 80 or so amps at first and four 6s can take twice that. Some inverter gens have 150a chargers, but that takes a 3000w gen to run it at those high charging amps.

Sounds like you could sell the 2200 and take the 3100 as your portable gen or VV depending on ? You don't need both anyway.