Confusion on battery charging

MEXICOWANDERER wrote:
UNTIL your batteries have been brought back to life yes it's going to take a few hours to fully charge the batteries. You are stuffing those amps into INCREASED capacity :)

Once your batteries have been mini conditioned correctly you do NOT have to do this each charge cycle. I would do it every 14th cycle and then it will not be the same time-eater as it is now. It will take 1/4 to 1/5th the time normally but you are not treating your batteries normal deep cycle duty. So they will recover much faster. Shallow cycles and occasional 100% charging is battery heaven for the Lifeline.

But fail to recover to 100% charged for a year or three no matter if the batteries get discharged 20% then you enter the syndrome you are experiencing. I would do as Lifeline suggests and set the Megawatt for 14.40 volts. It can chop an hour or two of recovery charge time versus 14.3 volts. And 14.5 volts does almost nothing except throw calculations off.

When you get back to public power I would leave the Megawatt at 14.40 volts for a full three hours. Calcium/calcium is very overcharge resistant. I have left my Lifelines on for 12 hours and they gained 3F at 32c. They are one heck of a good battery.

This makes some sense to me. Maybe I fell behind in achieving full charge over the past couple of weeks. The batteries are new as of a few months ago and have only been used for the past month. Before that they sat a couple of months with a 13.3v float. Maybe even new unused batteries need a jolt at 14.3. I left them on float until I started to travel since I was afraid of overcharging with no use and a daily 14.3 cycle.

I may have electric hookup tomorrow that should get them charged and then they can bake at 14.3 with the solar. After that things might be downhill. I am traveling to the Olympic peninsula with lots of clouds and fog.

They are attempting to -estimate- the amount of time it takes to fully recover to 100%. A stuffed Lifeline.

Thankfully the batteries do not need to be stuffed every time. 14 discharges 14 days whichever comes first is my rule of thumb.

With solar voltaic time must be purchased. Amperage versus the length of time sunlight is productive. There is a choice a) a small generator and a Megawatt, or double the potential of solar amperage at the initial stage of bulk charge.

100 amp hours of Lifeline = charge acceptance of 100 amps initially. How many hours of sunlight does it take to drop amperage to LESS than potential maximum of panel output?

This is "variables city" and it changes by the length and the quality of the solar day. Easy to calculate it isn't. Forecasting this is impossible.

8 hours of beneficial solar but what is the ampere hour yield? Another of my rule of thumbs is ampere hours divided by 40% is a good compromise for high latitude solar panel sizing. Yep 40 amps of panel spec for each 100 amp hours of AGM battery. You have a 40% reduction of harvest at winter solstice on the best of days.

It doesn't matter folks

You undercharge flooded batteries and you will need to equalize them. Hour after hour after hour. Voltmeter, special amperage throttling, and a hydrometer. Pick your poison. AGM is easier to deal with...period.

Hell. I have a tiny 2-cycle Harbor Freight 700 watt generator to power a small Megawatt. Fill the generator, run it until it runs out of fuel, a whole quart and a half. The Lifeline will be stuffed. Sorta dumb to feed a five thousand watt generator to do this...

Campground Quiet Hours make it more complex. Then it may be necessary to snow-shovel amps into the Lifeline and maintain a 14.40 volt charge rate at full absorbsion voltage. This means using near 100-amp capacity chargers. I used to generator charge from 8:00AM to 10:00AM with the generator then let the panels take over.

When the Kubota/Kato goes online I do not screw around. 500+ amps at twenty eight volts. I am not going to toss my money at millionaire oil speculators. Nor am I going to screw up the best AGM battery on the market.

AS far as lithium goes, I wonder how pricey 3,300 amp hours of 24 volts is? Rather spend that kind of money on a Phantom Extended Chassis.

I don't understand their "recommended Absorb time" of 2 hours for DOD under 30%. They have the equation for Bulk that takes into account bank size in AH, DOD, and charging amps (constant in Bulk) but then just tack on another two hours regardless of bank AH size.

It might be they assume the acceptance rate for any size bank will be met by the charger during Absorb, but what if the charger (solar) can't do that many amps? Still two hours?

I know how it works with flooded batts as in my ugly graph on that, but these Lifelines have their own rules it seems.

UNTIL your batteries have been brought back to life yes it's going to take a few hours to fully charge the batteries. You are stuffing those amps into INCREASED capacity :)

Once your batteries have been mini conditioned correctly you do NOT have to do this each charge cycle. I would do it every 14th cycle and then it will not be the same time-eater as it is now. It will take 1/4 to 1/5th the time normally but you are not treating your batteries normal deep cycle duty. So they will recover much faster. Shallow cycles and occasional 100% charging is battery heaven for the Lifeline.

But fail to recover to 100% charged for a year or three no matter if the batteries get discharged 20% then you enter the syndrome you are experiencing. I would do as Lifeline suggests and set the Megawatt for 14.40 volts. It can chop an hour or two of recovery charge time versus 14.3 volts. And 14.5 volts does almost nothing except throw calculations off.

When you get back to public power I would leave the Megawatt at 14.40 volts for a full three hours. Calcium/calcium is very overcharge resistant. I have left my Lifelines on for 12 hours and they gained 3F at 32c. They are one heck of a good battery.

JimK-NY wrote:
BFL, thanks. I cleared out the excess stuff I used to carry including the multimeter. I did check the voltage reading on the truck. It showed 12 volts and the camper is at 14.4.

You can't RV without a multimeter!! EG you could be using it to check if your solar display is telling the truth.

I did have to go up a notch with mine, so it has a fuse you can replace nearly every time you try the amps mode. Got tired of buying new cheaper multimeters that just fry and no fuse. :(

BFL, thanks. I cleared out the excess stuff I used to carry including the multimeter. I did check the voltage reading on the truck. It showed 12 volts and the camper is at 14.4.

JimK-NY wrote:

BFL13 wrote:
........

Is the camper plugged into the truck when you are parked? If it is and the truck is a Chev, there will be a draw from the truck.

I have also wondered if this is a possibility. My truck is a 2018 Ram 3500 CTD with 2 AGM batteries. I do have a battery isolator built in to the camper but I am really not sure how it works. I know it is supposed to prevent the camper from draining the vehicle batteries. I don't know if it allows them to be charged from the RV.

That's easy. During the day, when camper voltage is above 13, put your multi-meter on the truck battery when the truck is not on, and see if the voltage is the same as the camper's.

charge efficiency is low <50% for the last bit of charge.

MEXICOWANDERER wrote:
That "Cheap Charge Controller" will act to fully charge an AGM battery better than a four hundred dollar multi-stage genius charger. It is set to 14.40 volts AFTER your solar panels DO NOT fully recharge the Lifeline and it does something no other machine will do

IT STAYS AT 14.40 VOLTS until you see .5% amperage.

You need a heart rending surplus of solar panels to do the same thing. Like FIFTY AMPERES WORTH. To buy the surplus time during the day to allow amperage to slump.

Do as you wish -- I tried to help. Lifeline is going to echo my words. Adios.

OK, so I get the charger and that will put 50 amps on the batteries until I reach 14.3. Then I guess I will still need to run the generator for another 6 hours or more to reach the 0.5 percent level. It is that very long time at 14.3 or 14.4 that I do not understand and that seems to be an issue reducing battery life. It seems I need to overcharge by about 10% (30 AH) every day which is more than I actually use. Maybe that is the way it is supposed to work but it makes little sense to me.

BFL13 wrote:
........

Is the camper plugged into the truck when you are parked? If it is and the truck is a Chev, there will be a draw from the truck.

I have also wondered if this is a possibility. My truck is a 2018 Ram 3500 CTD with 2 AGM batteries. I do have a battery isolator built in to the camper but I am really not sure how it works. I know it is supposed to prevent the camper from draining the vehicle batteries. I don't know if it allows them to be charged from the RV.