Dead battery

We have a 2007 Ford Escape, primarily driven by our teen daughter. She usually drives 4 or 5 miles a day to school and back on city streets, with rare highway driving. Recently failed to start with battery less than 6 mos old. Took car to Ford dealer, thinking there might be an electrical issue. They checked everything, their evaluation the car was not being driven enough to charge the battery. They recommended a weekly drive at highway speeds to keep the battery charged. Does that sound right?

Yes. Short drives all the time can kill a battery in short order. A drive for 20 to 30 minutes every few days will help keep the battery fully charged and health.

The batteries used today are filled with a gel, so you never need to add water. However these batteries do not take a charge as fast as the older batteries where you added water. Reason, is a fast charge would cause the battery to lose too much fluid and shorten the life. So, when you only drive a car a few miles with lots of starts and stops the alternator isn’t spinning very fast either. Combine these 2 factors and add the drain on the battery from frequent use of the starting motor and you end up with a less than fully charged battery, and eventually a completely discharged battery. A truly dead battery has broken down internally and can’t take and hold a charge anymore. A discharged battery isn’t dead, it just needs to be recharged back to a fully charged state.

If more driving isn’t practical on this car, buy a battery tender type of charger and hook it up monthly for a couple of days. That will bring the car up to a full charge at least once a month.

In addition to short drives, I suspect that she leaves the fan on high all the time. Low speeds with the blower motor on high and headlights on will keep the battery from getting a charge.

Gel batteries? I am familiar with optima batteries which are AGM. Is AGM a gell battery or not? And some new cars have these batteries? No more lead acid batteries?

I guess you can get a battery that’s a gel cell, but most car batteries are still the old liquid lead-acid variety, even the “sealed” ones. Today’s cars use more electricity than ever before. In the 70s, your main loads were your heater fan, lighting, and rear defogger, if so equipped. Today you have stereos cranking out 300+ watts, nav systems, ABS, high-energy ignition systems and 6 or more computers all drinking from the trough. Plus the same loads that 70s cars had. And with manufacturers trying to squeeze every little MPG they can, you have alternator deactivation and very low idle speeds. True, today’s alternators do kick out a lot more current than older ones, but they still have to be spun at a reasonable speed, for a decent amount of time to charge a battery.

I totally agree that short trips could be killing your battery, especially if your daughter runs everything at full blast, and during winter and spring months where you’re using the heater, defogger, wipers, and lights more than you normally would in warmer months.

Not only will occasional longer trips help your battery, but they will help the car last longer–an engine needs to get good and hot to cook off condensation and other volatiles in the oil, and to burn off carbon deposits, and short trips all the time aren’t helping.

They also make solar trickle chargers you plug into the cigarette lighter port that would probably do the job. Plug it in at work and let the sun do the job of recharging the battery during the day.

AGM batteries are still a lead-acid variety. I understand they are like a fiberglass fabric soaked with acid inside between lead plates. They are supposed to be great batteries and of course cost more.

As for the battery dying so fast, did you replace it with a value grade from a parts store or Wal-Mart? All these places usually have 3 grades. They have a value line, a mid-grade line, and a premium line. Pay the extra money for the premium line as they do last longer and carry a much better warranty. My experience with using the value line has been that they are a joke and that you definitely get what you pay for with batteries. I seem to remember the value grades being black, the mid being red, and the premium being yellow/gold in color. This might not be everywhere but I think Wal-Mart and most parts stores have them colored this way.

This would be a good application for an electric car.
I wonder what a Leaf would cost with a half-size battery?
A worst case range of 50 miles would be plenty for this driver.