Increasing battery capacity

tim1970 wrote:
If I were to have 2 pairs of 6 volt batteries (4 total) would the recharge to 90% time double?

Almost twice as long but with same energy use it would be every other day or maybe you would go a whole week and just charge when you get home. A set of 4 does give more flexibility to decide when and how long to charge.

tim1970 wrote:

If I were to have 2 pairs of 6 volt batteries (4 total) would the recharge to 90% time double?

If you're starting out from the same state of charge, with a 60A converter, it would take longer but not double (as the charge rate, particularly with one pair of 6V batteries, would be limited by the battery acceptance rate a good part of the time rather than the converter's output capability).

However, in real life, things get a bit more complex as you presumably would not be discharging the bank as deeply, since it now has twice the capacity and you probably aren't using twice the power. You might be recharging from 70% to 90% rather than from 50% to 90%. It's a bit harder off the cuff for me to predict how the time would change in that scenario, but at any rate it would not be twice as long. The main advantages are that you can go twice as long before needing to recharge and, if you need to use high powered devices (say an inverter powering a microwave), the batteries each supply only half as much current and so can keep up a good bit more easily and with less voltage drop during the usage. Usable microwave operation time would more than double.

Too many variables here..

2-6 volt batts... 230 ah's. You can run them to 50% so about 115 ah's you have.

Two TV's @100 watts = 16.6 amps. Plus your other gadgets and such. Lets figure 25 amps an hr.

You can run your stuff about 4 hours.

Plus losses from your inverter and such, but lets say 4 hours.

Now you need to charge those batts back with what you took out.What converter do you have in your camper? If its a WFCO I doubt it will go into bulk mode 14.4 charging. It most likely will stay in 13.6 mode as these WFCO's are problematic.

Plus the small wire you may have from converter to batts you may be lucky to see 20 amps charging.

It would seem 5 hrs charge time if the converter stayed @ 20 amps, but its going to taper.

Moral of story with what you may have and your high load use it will take a while to charge those batts back up. And two more batts ( 4) will take longer if you run them down 50%.

Of course you can run longer say 8 hours with your load and 4 batts..

Do you have the room for said batts?
Are you willing to spend money to upgrade converter charging section and possibly wireing?
Do you want to spend money on solar to help the cause?

Cheap way out would be an external charger run off the generator.And if your going to spend that money you may as well get something you can mount close to batts and charge from that device and be in more control with a charge wizard to force into bulk,

But possibly you have an IOTA converter?

We dont know..

You can dump 70 amps into two 6 volts and 130 amps into 4.



An 80 amp charger here mounted close to batts will charge at the preferred 14.8 volts and net you the amps you want.

http://www.bestconverter.com/PD-9280C-148-80-Amp-RV-ConverterCharger_p_620.html#.Ww9nvEgvyUk

But make sure you want to boondock before you spend the $$$. Some deep 6 the idea after a few attempts and realize its easier to just plug into a pedestal.

This was the beggining stages of my set up.

I have two 280 watt panels now, and a different 40 amp solar charge controller...

https://www.youtube.com/watch?v=fD5cpclHjqA

time2roll wrote:
I still think 300w will run all that.

Recharge is 2 to 3 hours to get close to 90%. Over 90% really slows down so may as well quit. Once the battery hits 14.2+ volts go another hour and call it done.

If I were to have 2 pairs of 6 volt batteries (4 total) would the recharge to 90% time double?

I still think 300w will run all that.

Recharge is 2 to 3 hours to get close to 90%. Over 90% really slows down so may as well quit. Once the battery hits 14.2+ volts go another hour and call it done.

IAMICHABOD wrote:

DrewE wrote:
There is of course also a fourth and even simpler option, which is to get a small inverter and plug the TV into the inverter and then connect the inverter to a convenient 12V power supply point, often a lighter plug where the TV is installed. That can be done by anyone who can plug things into other things, and for a pretty small load like a TV it usually works fine. (An XBox may prove more troublesome, as it's comparatively power hungry.)

This is what I did,I had no need for a large amount of power while off the grid nor the expense of a larger inverter.

The TV is all I wanted to use and it was not a 12volt.
This one works just fine.

I did the same thing and just use a cheap wall mart inverter to run the TV

My TV does not need a pure sine wave to work ,works fine on modified .

Yes, amps at 12 VDC is 10x the amps at 120VAC. amps = watts/volts whether it's AC or DC.

Thanks for the help. I won't need to run anything major like AC,Hair Dryer,Microwave, etc, but I definitely will need to run 2 tv's, 2 satellite controllers and 1 satellite dish at the same time. So I am thinking about a 1000w inverter.

But I need help with the math. If I have an LED TV that uses 100 watts (I know this is probably a little high), then I divide that by 120 volts which equals about .83 amps. Now here is where I am confused. SInce I will be running this off of a 12 volt inverter, then would I need to divide the 100 by 12? This would equal about 8.3 amps of draw on the battery. The reason I ask, is this makes a big difference as to what size battery bank I need.

Now my plan is to recharge my batteries every morning with a generator, so assuming I get dual 6volt batteries (~205 AH), how long will it take my generator to charge them? (Assuming I will be using the converter/charger that came with my camper. (2017 Jayco 29.5 BHDS)

Edit:

I just checked and I have a 60amp 4 stage converter/charger rated at 1000 watts input, so a 2000 watt generator should charge it just fine, but I am not sure how long it will take.

If it’s just for TV, I’m in the use the cigarette lighter option for a small inverter. I hardly ever use my 300 watt hardwired inverter.