Battery draw and charge DC to DC battery charger.

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I have Batteries from Batteriesplusbulbs.com. The auxiliary batteries are Crownbattery.com  case GC2, AGM, 4x, 6v, 12v wired correctly 220 ah, 440 ah total.
The start battery is also from Batteriesplusbulbs.com a X2power AGM,  case 34, CCA 880, RC 133. The battery says it will do 400 cycles to 80%.
I put in a 160 amp alternator (new part, lifetime warranty.) 

The DC to DC battery charger is from Renogy.com and is 60 amps. Cost $260 (The 50 amp version is 25 amp solar, 25 amp DC to DC charger. Cost $300)
Wiring from the start battery if a long distance is expensive to have them installed from engine area to under vehicle to DC to DC charger (I used 1/0 welders cable.) Wiring from output is 4 gauge, use welding cable and have them put on ring terminals.
Now the only problem I have with the DC to DC battery charger is that it charges the start battery. (So if the lights on the van are on or the car stereo is running the auxiliary batteries drop in voltage (if fully charged.)

Now I'm needing some help with what is the break in period in the number of cycles for these AGM batteries.
Also how far in voltage and percent do I discharge the batteries with this break in period.

At this point my load (besides charging the start battery) is a 50 watt 33% duty in the summertime chest refrigerator. Guesstimate is 400 watt hours in summertime.
1 amp fan O2-COOL.COM 12vdc 8 or 9 inch fan (no longer for sale.)

Other loads in the future are 12vdc.
40 watts tablet. (Internet connection)
Smartphone.
~69 ah recharge laptop battery. (DC to DC converter 12vdc to 19vdc, no vampire draw when unplugged from laptop.)
Unknown maybe 23 inch tv/monitor. (Any idea wattage?) (Any suggestions)
New Car stereo kenwood car stereo, (10 amp max) (I'm hoping more energy efficient than Dodge Grand Caravan stereo.)

I think I've included most everything, if I think of anything else I'll post.

I live in Salt lake City, Utah because I have to take a lot of medications and can't go south for the winter but have followed the site a long time before it got more developed.
 
I have never heard of a break in period for batteries. do you have a reference link or something that says that. curious in Arizona. highdesertranger
 
I came across two different references. One was AGM and one was liquid lead acid. The AGM battery was to cycle down to 80 percent discharge (20% left) but i don't remember how many times (best guessing from memory was 8 times but i don't really remember.) The reason I was investigating is that my battery bank isn't reaching the full 13 full volts or 12.95 soc with rest. Also i was recharging a couple of times to 14.42 a day, then stopping at float 13.8?. I was using so little with the fridge and other stuff that I could recharge in less than 45 minutes (guessing.) The Renogy DC to DC battery charger fan doesn't turn on or produce any warmth.

The wet battery hits it's stride after 50 cycles.

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StitchExperiment626 said:
Now the only problem I have with the DC to DC battery charger is that it charges the start battery.

Do you have something else, like solar, to charge the auxiliary batteries?  Is this the way you want it to work?  Did you connect the output to the starter battery and input to the auxiliary batteries?
 
To clarify the DC to DC battery charger from a Question and answer sesion the auxiliary batteries recharge the start battery and I was surprised at why they would design it that way. I wouldn't want it that way but for 60 amps of charge, I got what I wanted. At a price of $260 after first time buyers discount and tax. I live in a van in a city and can live only a week or so outside the area because I take a lot of medications and run a chest refrigerator to store the medications.

I see a lot of different information about batteries on the internet. For example I have seen on a marine website that a fully charged AGM battery is 13 VDC. My batteries are Crownbattery.com manufactured in Canada and i just got information from them that a fully charged AGM battery is 13.84 volts and 75% is 11.04 volts.
FYI it says at below 32 f be above 60% charge.
These Canadian batteries I think are designed for a colder climate and the reason is that they say they go down to - 40 f and c.
Optimal testing conditions are at 80 degrees Fahrenheit and going up 15 degrees Fahrenheit doubles chemical reaction which is not good but the battery will go up to 120 degrees Fahrenheit max.
Now to find out more about my start battery.

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StitchExperiment626 said:
I was surprised at why they would design it that way. I wouldn't want it that way

Did you connect the output of the DC to DC charger to the starter battery?

Did you connect the input of the DC to DC charger to the auxiliary batteries? 

If you got that wrong then it would work as you describe.  Reverse it and it will charge the auxiliary battery when you drive.
 
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