Battery questions

[ib516]

I know there are some very knowledgeable folks on this topic, hoping you'll chime in.

Current set up is a small 17' hybrid that HAD a new (Costco), single group 27 12v (105 AH) battery. I use a 2000w inverter generator to charge it using the on board converter. I also have a 2500w modified sine wave inverter attached for running a 760w coffee maker in the morning before generators are allowed to run (9am to 1030am and 5pm to 7pm ONLY). Well, I completely fried that G27 battery (Costco brand). I neglected to check the water level and had to add about 500-750mL of distilled by the time I thought to check it. Also, the 5 min it took to brew a pot of coffee would basically kill the battery. It would go from 12.3-12.4V down to 11.7-11.6V to brew one pot.

So, I got rid of the G27 12V battery, and need an upgrade.

Here are my options:

• 2 of the same Costco (but new) G27 12V 105AH batteries that I will be more diligent at checking electrolyte levels
• 2 12V AGM batteries ($$)
• 2 Costco 6V golf cart batteries listed as 208AH @ 6V

Which of these would be best?

[OldSmokey]

MEXICOWANDERER wrote:
Koffee out of a kup machines draw a lot more power because their heating element is stronger to brew faster. Enter the Benefit/$$$$ ratio compromise. Sort of like asking if a ten horsepower lawnmower would get the job done 5x as fast as a 2 horsepower lawnmower thereby saving gasoline...and money.

Like bringing whole bean coffee to the mountains.

Grind coffee by pulverizing coffee on a granite boulder with a ball pien hammer. Fill a pot with water. Boil over a pine knot fire. Toss in a hand-full of smashed beans, count to thirty, remove pot. Splash in a dollop of cold water, then pour into a corrosion resistant cup, preferably and all metal one that seals the lips to a searing hot coffee cup lip. Tip - try to avoid sampling the last 1/4" of liquid remaining in the cup. A 24-volt jump-start on the day.

Uncoated fry pans make great toasters. right over the coals. the best ones are heavy cast iron. But many times the mule protests a 120 pound load and revolves repeatedly on the ground with hooves pointing straight up. A second mule can be compared to a second battery.

Is it worth stoking a fire overnight to get your first cuppa joe?

Decisions / Compromises.

It's what makes camping CAMPING

LOL !

[OldSmokey]

time2roll wrote:

sportsman 500 wrote:
Been lurking here following this thread. I have a similar question but different hardware. I have a Kuerig coffee maker that brews one cup at a time. The initial warm-up lasts around or under 3 minutes drawing 1500 watts. The water tank re-heat cycle after brewing is 200-400 watts and lasts around 60 seconds. At idle the Kuerig draws 60 watts.
I would be running this with a 3000 watt inverter solely for the coffee maker. Trying to keep weight down I would like to keep it to 1 group 27 or 31 deep cycle. How long do you guys think the one battery would go if starting from fully charged?

Sine wave? The heater does not care but the electronic controls may fail.

Why 3000 watts rated to run 1500 watt appliance?

I think Kuerig makes a 'hotel' version that draws closer to 700 watts and would be far better on inverter and small battery.

Yes the battery may brew a few cups but you are going to kill the battery with very hard use.

To properly drive 3000 watts you should have 6+ batteries. Even at 1500 watts you should have three or more. The Peukert effect will have a single battery depleted twice as fast as a normal calculation. Then you need to charge it up 6+ hours to go again the next day.

3000 Watts ? I'd like to know too..

here are some figures to look at for battery capacity vs discharge
using your 1500 W load and normal deep cycle lead acid batteries.

1500 W @ 12 V = 125 Amps needs a 500 Ah battery with 2 AWG cable minimum
1500 W at 24 V = 62.5 Amps needs a 250 Ah battery with 6 AWG cable minimum
1500 W at 48 V = 31.25 Amps needs a 125 Ah battery with 10 AWG cable minimum

for AGM you can half these capacities
for Li you can go one third.

see where this is going ? i'm using c/4 here and that's high for solar re applications, normal would be c/6 or c/8 however this is rv and you have more room to abuse batteries.. LOL

pulling 1500W from a tiny group 27 is going to kill it very quickly.
if you REALLY want to stay with 12 V batteries then I suggest you
use a 12V 200Ah 4D AGM, it's heavy, expensive and can discharge at c/2 comfortably and will last longer than abusing a G27

[MrWizard]

Dave
I see your smiley face

Not gross, no different that buying some refrigerated Starbucks out of the cooler at 7_11

And there are millions that do that
Probably more than a few of them on here 😛

[red31]

pnichols wrote:
No mess to clean up, no noise, no solar, no inverter, and very little electricity period (.... except for the spark from the pizzo-electric burner igniter). :B

simple and it works.

[MEXICOWANDERER]

Koffee out of a kup machines draw a lot more power because their heating element is stronger to brew faster. Enter the Benefit/$$$$ ratio compromise. Sort of like asking if a ten horsepower lawnmower would get the job done 5x as fast as a 2 horsepower lawnmower thereby saving gasoline...and money.

Like bringing whole bean coffee to the mountains.

Grind coffee by pulverizing coffee on a granite boulder with a ball pien hammer. Fill a pot with water. Boil over a pine knot fire. Toss in a hand-full of smashed beans, count to thirty, remove pot. Splash in a dollop of cold water, then pour into a corrosion resistant cup, preferably and all metal one that seals the lips to a searing hot coffee cup lip. Tip - try to avoid sampling the last 1/4" of liquid remaining in the cup. A 24-volt jump-start on the day.

Uncoated fry pans make great toasters. right over the coals. the best ones are heavy cast iron. But many times the mule protests a 120 pound load and revolves repeatedly on the ground with hooves pointing straight up. A second mule can be compared to a second battery.

Is it worth stoking a fire overnight to get your first cuppa joe?

Decisions / Compromises.

It's what makes camping CAMPING

[pnichols]

This is going to offend the coffee purists even more - in fact a way over the top offense that probably is a travesty:

I heat up instant coffee on a burner of the RV's propane cooktop stove. I even use a titanium cup to drink it out of that can itself be directly placed right on the burner.

I wipe out the cup with a paper towel so it's ready for the next time. No mess to clean up, no noise, no solar, no inverter, and very little electricity period (.... except for the spark from the pizzo-electric burner igniter). :B

[dave17352]

MrWizard wrote:
This is going to 'offend' the coffee purists

I use a drip maker, and most of the time i make a pot when the generator is running, which i then put in a Thermo carafe,

But my early morning first cup of coffee , comes from yesterday's carafe and i put in it the MW to heat it up

On occasion the carafe is empty and i make a new pot using the inverter
Approx 900 Watts for 10 minutes
But.. I have the battery bank to do that
This cloudy 8:30 am morning, 12 hours after the generator was turned off
My batteries were at 79% SOC, last night i watched TV until 11pm, then was on the pc for an hour, before going to bed at 12:25 AM
I tried a French press, i like the coffee, it's too much hassle in the morning, for my 'wake up' needs,

Ok Mr Wizard that is just plain gross! I mean the first cup thing:)

[SoundGuy]

MrWizard wrote:
This is going to 'offend' the coffee purists

There's more to this than being a "coffee purist". The question is often asked why, if one is dry camping, you wouldn't just make coffee using some method that doesn't require any electrical power at all. Fair enough for those who dry camp regularly BUT for those of us who normally camp on an electric site and only occasionally might find ourselves without shore power the answer is simple - we'd prefer to just make coffee, toast, etc, the way we normally do. For that, I have a 1000 watt inverter which is plenty for powering either ... no need to carry anything different than we normally have on hand. It's simple and it works. :B

[2oldman]

MrWizard wrote:
But my early morning first cup of coffee , comes from yesterday's carafe and i put in it the MW to heat it up

Me too. I want as little hassle as possible first thing. I have plenty of battery to run the MW.

[MrWizard]

This is going to 'offend' the coffee purists

I use a drip maker, and most of the time i make a pot when the generator is running, which i then put in a Thermo carafe,

But my early morning first cup of coffee , comes from yesterday's carafe and i put in it the MW to heat it up

On occasion the carafe is empty and i make a new pot using the inverter
Approx 900 Watts for 10 minutes
But.. I have the battery bank to do that
This cloudy 8:30 am morning, 12 hours after the generator was turned off
My batteries were at 79% SOC, last night i watched TV until 11pm, then was on the pc for an hour, before going to bed at 12:25 AM
I tried a French press, i like the coffee, it's too much hassle in the morning, for my 'wake up' needs,

[RDMueller]

I have 2 6v golf cart batteries that serve me quite well when dry camping. For a typical weekend trip, they have plenty of capacity to get me thru the weekend without any charging. I have even made it thru a 4 day day trip without going below 50%. That's without any furnace use though.

Now as far as coffee... Typically I always heated water on the stove and made French press coffee when dry camping. I have started to experiment with drip coffee using an inverter though. What I've found is that my coffee maker draws about 72 DC amps and as long as the batteries are above about 60% to start, the inverter won't alarm.

So for me, if it's just a quick weekend trip and I don't plan on running the furnace, I'll make drip coffee. For longer trips or if I expect to run the furnace, back to French press coffee!

[time2roll]

sportsman 500 wrote:
Been lurking here following this thread. I have a similar question but different hardware. I have a Kuerig coffee maker that brews one cup at a time. The initial warm-up lasts around or under 3 minutes drawing 1500 watts. The water tank re-heat cycle after brewing is 200-400 watts and lasts around 60 seconds. At idle the Kuerig draws 60 watts.
I would be running this with a 3000 watt inverter solely for the coffee maker. Trying to keep weight down I would like to keep it to 1 group 27 or 31 deep cycle. How long do you guys think the one battery would go if starting from fully charged?

Sine wave? The heater does not care but the electronic controls may fail.

Why 3000 watts rated to run 1500 watt appliance?

I think Kuerig makes a 'hotel' version that draws closer to 700 watts and would be far better on inverter and small battery.

Yes the battery may brew a few cups but you are going to kill the battery with very hard use.

To properly drive 3000 watts you should have 6+ batteries. Even at 1500 watts you should have three or more. The Peukert effect will have a single battery depleted twice as fast as a normal calculation. Then you need to charge it up 6+ hours to go again the next day.

[SoundGuy]

sportsman 500 wrote:
I have a Kuerig coffee maker that brews one cup at a time.

I would be running this with a 3000 watt inverter solely for the coffee maker. Trying to keep weight down I would like to keep it to 1 group 27 or 31 deep cycle. How long do you guys think the one battery would go if starting from fully charged?

Your Keurig is the problem - it draws WAY too much, so a single G27 or G31 won't run it at all without the inverter alarming almost immediately. My own 550 watt Cuisinart coffee maker runs well enough using a single G27 as source power without causing my 1000 watt PSW inverter to alarm provided the battery is fully charged but less than a full charge and the inverter will alarm. My 750 watt toaster causes the inverter to alarm regardless. Since we do this infrequently my solution is to load support my single G27 with my truck, as described earlier.

[2oldman]

sportsman 500 wrote:
.. Kuerig coffee maker that brews one cup at a time. The initial warm-up lasts around or under 3 minutes drawing 1500 watts.... ... I would like to keep it to 1 group 27 or 31 deep cycle. ?

It's difficult for me to imagine one battery handling 1500 watts (at 12v) for more than a few seconds. That's 130 amps. Like running your a/c.

My experience shows that you need at least 4 and preferably 6 T105s for something like that. If you want to keep the weight down and have deep pockets, look at the Relion Lithium batteries. They don't sag in voltage under heavy loads.

It's also better to go to a higher voltage inverter, like 24 or greater, to cut the amps draw down to where you don't heat up the wires or batteries.