Hasn't anypone done any measuring to identify the amount of battery drain? Or is everyone guessing? First of all, with everyting off includig the engine, measure the amount of current drain at the battery terminals. There can be a very samll anount taken by the clock and 'keep alive' memory. A security system may take the most. The draw should be very samll, in the millamp ramge. A good repair manual may have the number, but these small drains are seldom discussed in the maintence manual if it is insignificent to begin with. Measuring the current draw may help identify the source. Maybe a small lamp is lighted. Hidden lamps are glove box, trunk lid, and under hood lamp. Some auto have a 'reading lamp' located in the rear passenger compartment. I had one that was on the wall above the rear seat. Its switch was not obvious. It was turned on by rotating the fixture. Once on, this lamp stays on even after the doors are shut and the suto vacated. It is manually operated. If a search of car turns up nothing, then its time to begin tracing where the leak is at. This could be a terdious process since it could anywhere or anything especially if the car has been lightening struck as stated above. If you are certain the damage was by lightening, it may be covered as storm damage by your insurnace. Check your policy. I know of one case where a Ford Van was fried by lightening. Many components were ruined including the engine controller (computer). The shop decided to replace the entire wiring harnesses including some lamp sockets. This seemed expensive, but the cost was on par with paying a technician to track down all damages, and then it could not be assured that everthing would be found. But before going the drastic route of complete replacement, try to ascertain for sure the cause of the damage. Did someone do a jump start and momentarily reverse the jumper cables? One or more alternator diodes could spoiled, for example.

I suggest looking at "Batteries Plus". Their products are not the lowest cost, but I have had good service from their products both for automotive batteries and rechargeables for cameras. I live in a cold climate but my vehicles may also see very hot weather. I have 2 vehicles: one a 4 wheel drive for winter service and a sedan for the remainder of the year. The sedan gets stored in my garage when hte first road salt hits the streets and does not come out again until salting quits. Its typcial storeage time is from Dec. 10 until April 30. During storage time, the engine may be started and run 3 to 4 times for about 45 minutes. This not often enough for best practice. It should be run at laeat once a month. The battery can be a little low on charge. It must be kept charged enough to prevent freezing. During the summer months, my winter driver does not get driven much. It, too, gets started and run if it has sat for more than one month. It is stored in a closed garage that gets hot inside. Depending on the purpose, either vehicle may be taken on a trip of 1000 to 3000 miles. My summer driver is preferred since highway mileage for these vehicles are 30 miles/gal for the summer car and 20 max for the 4 wheel drive. My batteries last on the average of 5 years. Some would go longer, but gets changed if I detect reduced cranking ability or the battery is 4 yrs old and I am preparing for trip where increased reliability is a must. (Believe me, you do not want to be 200 miles from the nearest service with a dead battery with no available phone, no available cell phone, CB, or other communication.) For your case, your batteries are failing early. Even for the cheap models, I'd expect much better service. You say that your charging system is ok and the vehicle gets driven every 2 to 3 weeks. Your battery should last several years. I suspect that the battery is not getting enough charge and/or something is draining the battery. Some of those 6 mo. old batteries that were thrown away may have been serviceable and only needed a good charging. In modern cars, there are systems that place a small drain on the battery. One is the "keep alive" current supplied to various memories, the second is the security system, and a third is the remote key fob system. However, a charged battery should be able to supply these systems for several months. Look for excessive loads such as a glove box lamp, trunk lamp, or underhood lamp that remains lighted all the time. In some cars, the interior "dome" lamp is controlled by a solid state switch. A leak may occur here if the switch does not fully turn off. If your battery is not getting fully charged, a trickle charger could help. A simplier solution might be to drive the vehicle enough to charge the battery. For a number of modern cars, the ignition system will not work if the cranking voltage falls to 9 volts.

I think it is. My car has a 25mA current draw when sitting idle (that might be high, I don't know..it's got a bit of add-on equipment). So even before we even consider self-discharge, that means the battery has lost 4.2 amp-hours of it's capacity sitting for a week. Self-discharge estimates vary, but it goes up with the temperature. I figured that with self-discharge, I might be losing 8 amp-hours of capacity by letting it sit for a week. I guesstimate that the battery is about a 52 amp-hour capacity battery. (Group size 58 if I recall correctly--whatever fits in a 1988 Mustang 5.0--the original factory battery is specified as a 52-amp hour battery--I would expect that the Diehard replacement is about the same capacity) Allowing a car battery to discharge below about 10% reduces it's lifespan. In this case, that would be 5.2 amp-hours. The solar charger I used is a 3.2 watt charger from VW. VW ships every car they make with one of these chargers to keep the battery from going dead. I got two of them off Ebay for $40 shipped. (Do a search for VW solar charger on Ebay to find them). They plug in the cigarette lighter. They're probably the best charger out there for this type of thing. I hooked one up and tested it--even without being in direct sunlight, it was putting about 50mA into the battery. I didn't test it in direct sunlight (mainly because the clouds weren't cooperating, along with the angle of the space I was parked in), but the label says it puts out 170mA.

Um... that's not quite the story. Since my name is on the subject line: There was a horse drawn wagon in my picture book. We had an automatic icemaker, and sometimes my folks froze blocks of ice in plastic containers, but when we were having a big party or going camping, my father would get a block of ice at the ice house, which wasn't far away, and he'd take me. He'd tell the story of the ice man whose horse knew the way to connect the blocks of ice with the horse drawn wagon in my storybook. When he was a kid they had an ice box. My mother only knew electric refrigerators, even out in the country. Sometimes, equestrians would ride down out of the hills, where there were some horse estates and trails, but that's as close as we got to horses where we lived. The milkman came in a panel truck and brought the milk inside and put it in the fridge. There was a breadman, I don't think daily, also in a panel truck, but one that opened up in the back with a display of breads and pastries, but my mother had a car and preferred to go to the bakery or supermarket. There are a few reasons primarily responsible for refrigerators not lasting so long nowadays. Electronics help meet energy savings goals, but are notoriously delicate. People want all kinds of gizmos, like crushed ice dispensers, which have never had a lot of longevity. The ice maker is the most likely place for failure. With all the plastic parts, which make shipping lighter, can be molded rather than wrought, and don't require metal ores (though petroleum is also a scarce resource), and overseas workforces who work for fewer dollars than North American workers, fridges are way cheaper in terms of buying power spent than they were ever so long ago, and far cheaper to replace than repair. People move a lot and move their appliances, which is hard on them. Landlords used to supply fridges.