Nevada That is what I am saying in my own way. I would suspect the alternator / regulator on my car does not provide 30 Amps of current to recharge its battery, based on what it takes for a battery charger to recharge a battery, low and slow is the preferred way, why would the mechanism in a car be set to quick charge? I do not think it would be. ( Yet I saw several run downs using 10s of Amps to calculate the recharge time. The re is a lot of misinformation out there in the interwebs…)
So your first step step should be to recharge the battery before you begin diagnosing other problems, you car can’t recharge the battery in 3 seconds or 30 minutes.
A car’s alternator can do a quick charge because a quick charge of an only slightly discharged (as from running the starter motor for 5 seconds) battery does no harm. Alternators are often 30A, 40A or higher. I assume that means they can at least for while put out that amperage at about 12 volts. Also if lots of electricity is being used while the car runs, the alternator can easily keep up with the need.
A slow charge is better for a very discharged battery.
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The OP’s battery is at 12.2 volts, operating the engine for 30 minutes has not recharged the battery. It depends on the resistance in the battery, a battery that has been discharged over a long period of time will draw a charge very slowly so even with the vehicles 90 or 120 amp alternator the battery may only accept 5 amps.
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Bing
I have been tending to think the battery is bad as well, I would just like to be able to prove it easily, I am seeing that that may possible in every case. 
After a 20-30 minute idle and a 4 mile round trip and 2 starts the resting voltage is 12.47. I will see what it is 16 hours later when I get up tomorrow.
Call me stubborn but I see it as I have already paid for this battery which is defective and cornered a bunch of my time and concern. Paying for a NEW battery would be paying twice for a working battery, getting a working ‘no cost’ replacement from Advanced Auto Parts, as they advertise, would only be getting what I paid ~ $160 the first time with a bit of bother thrown in for free. Wis me luck 
How would I measure the rest draw on the battery. I am thinking putting an Ammeter in series at the positive terminal would be OK if I left the car with all doors closed for say 10 minutes before disconnecting the cable.
It’s a 2012 model year, right? It’s six years old, so it has worked for six years. That’s three years longer than the one I had in my 2012 Acura. Seems to me you got your money out of it already. At any rate you need a conductance battery tester that will test the CCA compared to the rated CCA. You can buy a cheap one for under $100 or you can have the old load test done that will test it under load. I test mine at least twice a year, spring and fall and hardly ever let a battery get older than four years, especially if winter is coming or the car will be at the airport in the winter for a while. Suit yourself though and keep the jumper battery charged.
Bing
No. As I stated the battery is still under the 3 year warranty , The OEM lasted about 4 years. The counter folk at Advanced Auto Parts did a bench test they claim passed. Gave me a print out saying such. While a new toy is always attractive I will pass on the load tester as I live in an already overstuffed condo .
I would still like to address the technique to test the current draw on the battery with the car at rest. Would what I described above not be the way to proceed??
Thanks Again for your help.
This is the cheap one I use and works on the lawn mowers too. Other than that, I’m no battery expert. Just replace if any question.
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If the battery tests good and is fully charged and it doesn’t crank the engine robustly, the problem is obviously not the battery. There’s a half dozen things you have to check for a no-crank when the battery tests ok
- battery connections corroded or loose
- ignition switch
- security system
- under-dash relay
- neutral safety switch
- starter motor
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I think it is not the ignition switch, security system, neutral safety switch as I got a very weak crank. I should have better described the situation at the beginning . With a low charge battery I am not considering the starter motor.
I am not at all familiar with modern cars, how much current goes thru the under-dash relay? I think though the low charge is pointing towards 1. Battery defect 2. Discharge at rest 3. Faulty charging circuit.
Now for the morning’s results:
The battery was at 12.27 V this morning about 17 hours later.
With headlights on 12.07 V.
I managed to get my clamp on Ammeter around the negative battery cable in 6 Amp range. When head lights turned on it spiked and then stayed well less than an Amp.
Now an interesting item (for me anyway): with door open hardly any reading if any at all. When the door was closed the reading goes up to close to an Amp for about a minute. I am guessing this means the car is ‘getting ready to go’ and then says what the heck false alarm, I am going back to sleep.
At this point I am hoping (and feeling) the bad battery diagnosis is the correct one, I plan to have a competing store down the block test the battery. 
Edit
Well the auto zone folk pretty much just put a device across the terminals that gave a % (it was 47%) and a voltage of ~12.2 which I take to mean it is about half way between 12.6 and 11.8. Running voltage was 14 something. Not really an edifying experience 
My plan: Check voltage everyday and Monday take my 1 hour ride and see if the voltage gets closer to 12.6. Also make sure my jump pack stays fully charged. 
BTW impressive array of emojis but no black car!
OK battery still working, fingers still crossed, jump pack still charged…
Happy Holidays to all !
Well FYI I still have the same battery working fine , of course it is still warm weather here…
I did disconnect an USB charger which IMHO should not have made a difference. There ‘may’ have been one more problem after that I just don’t remember, 
The winter maybe a different story…
This sounds like a battery that’s been chronically undercharged due to infrequent use and short trips.
A battery that’s at 12.2V needs a slow, full charge at 14-14.5V for at least 6 hours.
I’m a weekend driver. I used to charge the battery overnight every 3 months.
Last battery I replaced was going strong after 9 years, but I didn’'t trust it for a 10th winter.
Even well cared for batteries life is shorter in very hot climates.
I now have a 10W solar panel on the top of dash that floats the battery at 13.2V in bright sunlight.
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circuitsmithThat sounds interesting! How is it done??
If you have a power outlet (cig lighter socket) on the dash that stays on with the car shut off it’s pretty simple.
Get something like this:
Plug it in and sit on the dash where the sun will hit it.
If no stay-on outlet you’ll have to splice into a constant 12V line.
Use a fused (10A or less) branch.
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I am thinking about getting one of those for the truck I don’t drive very often. My question is it does not have a stay on outlet I would be running a wire from the battery to inside the truck with am inline fuse what gauge of wire would be best?
There’s likely no need to run a line through the firewall.
What I did was probe wires coming off the fuse panel under the dash and splice into it.
I used a meter with a needle probe (a safety pin will do) to poke into wires until I found one with 12V (car off).
The thinner wires are fused branches.
Then clamp a ground wire to a bracket bolt or find a ground wire (they’re generally black).
I added a connector hanging where I can easily reach it while sitting in the driver’s seat, yet won’t interfere with my legs & feet getting in and out.
I also added a blocking diode to sub for the one built into the cig lighter plug.
The panel puts out less than 1 amp so the 22 gauge wire that comes with the panel is heavy enough, as long as it’s on a small fuse branch.
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Thank you that help’s a lot.
@ [circuitsmith]
Thanks for the idea, I have finally got around to looking into this. I have a 2012 Honda Accord EXL4 cyl. it looks like the power outlets are not live. I m a bit hesitant to screw around with wires under the dash or really wanting crawl in upside-down to find a live wire. Same with puncturing the firewall. If I knew just where to look I might be more confident.
I was hoping I finally found a use for my Moon Roof 
I would like to do the solar charger, but I do not know where to tap in to 12v unswitched. I would find it hard to get under the dash these days for long enough to poke around. Would a small hole in the fire wall be a very bad idea?
I do feel the battery is stating to struggle 