2010 - Sudden 12V Battery Failure

Yes slightly.
Simply leaving it connected longer will make up for all but the most drastic low temps.
And when you take it back out in the cold again, the available capacity goes down as it gets cold again any way.

I guess I'm gonna have to look at the BatteryMInder just out of curiosity; later, don't have much time right now.

I recently got a 2/10/50 Cen-tech charger from Harbor Freight because........the price was right (cheap).

I am testing it now on my Fusion Hybrid and after only about 20 minutes there are some interesting, but not surprising, results.
I didn't even notice that it has a "regular/AGM" switch but preliminary indications are that it does NOTHING.
It also has a light that turns green when "fully charged" but it show green on the 2 amp range but not the 10 one.
More later but it sure looks like just a plain old manual charger to me but I figured that going in.

 

interested in what you're going to figurev out here; especially the 'regular/agm' thing/

 

I don't think that is a good idea because batteries give off fumes when being charged. If you need to bring your battery in the
house to charge it its time to buy a new one!!

 

IF a charger accurately measured battery temperature, AND adjusted charging voltage accordingly (for instance: at 32F, charging voltage was upped 0.6v), would not that charger be EQUALLY effective out in the cold?

 

I'm not sure I understand whats going on here. I lived for 55 years in Erie ,Pa where the winters were very cold and in Texas for the last 17 years where it is very hat. My batteries have always lasted for 4 or 5 years with out having to charge them all the time. If you have to charge them its time for a new one. Once they don't hold a charge it's time for a new one. If you have to use jumpers or charge it to turn over the ICE it,s time to go buy a new one. The exception would be if you let the car set for a extended period. In that case i would disconnect the battery

 

Toyota should create a code and warning message: check 12V battery. It would warn me about a low key fob battery but not the 12V?

 

I understand the battery is different. I still maintain that if it doesn't hold a charge you need to replace it or it will leave you stranded. My battery in my 2010 Prius is the original battery and I have never had to charge it. I'm getting ready to change it now because of its age.

 

I don't believe anyone is disagreeing with this statement.

But not everyone would agree with this blanket threshold for buying a new one. Though it may be applicable for your particular auto use pattern.

 

If your battery has past 4 years have a plan for someone to come and get you and have your vehicle towed. Been there done that and wore that greasy shirt. The $200 that the dealer charges is good insurance plus you can get it done when you are off work and not on the way to work. Like to be dead in the water at 0400 AM on the way to work in the middle of no where. Granted once you get it started you might be ok.

IMHO have brakes that work, good tires, a full tank of gas, emergency supplies and tools in the car, and a battery in top notch condition.

I know you youngsters like to live on the edge. Unfortunately I have fallen off the edge and can't get up. LOL

 

I erred. "Trigger, not "threshold".

 

When my wife and I both worked and each had a daily 25 to 30 mile one way commute, our car's 12V batteries stay charged from daily driving and needed no supplemental charging. Now that we are both retired, our cars sit more days than they are driven. The Prius is driven only on short local trips and the Avalon gets a few long trips per year. So now their batteries need to be hooked up to a charger/maintainer to maintain their charge level and lifespan. So it really depends on how you drive as to whether you need to supplement the charging of your battery. In any case, after four to five years, you have gotten nearly all the life out of a modern battery and are living on the edge of being stranded. At this point, there is apparently no aftermarket direct replacement for the 57Ah Panasonic AGM battery in my Avalon and the dealer cost for a replacement is around $320.00.

 

I used to help raise cattle when I was growing up, and one way to guarantee yourself a lot of extra trouble with birthing calves, is to "do too much" by hovering around a birthing cow when she's in labor. The trick is to leave well enough alone, and intervene only when necessary. People who micromanaged the process too much, had excessive veterinary bills and high mortality rates.

I believe the same philosophy applies somewhat to a lead-acid battery. Obsessing with it too much, giving it booster charges when it doesn't need it, only shortens it's life. It can also be quite messy and even dangerous.

 

Please understand that my findings apply ONLY to this particular (cheap) charger but so far I have not found any situation in which the AGM switch make any difference it the charging voltage.

I first tried it on both the 2 and 10 amp charging ranges while the battery was down a bit and actively charging; switching the AGM switch made ZERO difference in the charging voltage.

After being connected for a few hours on 2, the "float" voltage was 12.8 and the green light was on with both 2 and 10 settings.
Since 12.8 is not really high enough a float voltage for any auto battery, it appears that something actually switches off when the green light comes on. That was a pleasant surprise. At that point, however, the AGM switch still did nothing on either charging range.

My conclusion: While some more expensive chargers might actually do something slightly different when an AGM switch is operated, this one doesn't.

AND......I still contend that you don't NEED a different setting for AGM batteries. It is fairly easy to design one that hits a happy median and will adequately charge both flooded cell and AGM just fine.

From the charts that have been provided lately, I now see why charging a GEL battery can be a little trickier as it requires LOWER voltages.
Putting a GEL battery in an older bike with charging voltages up around 15 might be a big waste of money.

Not true for a sealed AGM......unless you do something stupid they give off ZERO emissions.

That is a bad idea for several reasons.
A proper battery "tender" is a much better solution.

But there is a big difference between not "holding" a charge and not being used in a manner to ever achieve a full charge over time.

ALL lead-acid batteries self-discharge when not actively in use, AGM types much less.
ALL of them are also damaged by being left in a discharged state.

These are simple concepts; don't try to make it more complicated than it IS.

Just because your usage patterns are not hard on the battery does not mean that nobody's IS.

Done right, none of that is true.

 

Question for the masterminds out there: if you lowered the system voltage by say, 1 volt, would the battery last longer?

 

What exactly is "system voltage" ??
The likely answer is NO.

 

You missed the part about being there constantly, micromanaging it, "doing it right."
The whole point is that few of us can afford the time to be there all the time, to "do it right."

OK, I'll speak slowly, if the charging circuit maintains the system at 14.4 volts, would lowering it to 13.4 volts make the battery last longer?

 

Yes. That is why modern charging system DO drop the voltage down to about that level if and when the battery reaches a full charge.
And that is charging voltage, not "system voltage".
When the battery needs a charge, an extra 1 volt is not a bad thing.

As to your other point, I agree with your general contention that obsessing over things can be a bad thing but taking 30 seconds to connect a battery tender when you know the vehicle will not be (or has not beeen) used for a while is hardly an onerous task.