why don't you need to charge car batteries like you used to in the olden days?

Question

Every November my dad religiously brings the car battery in to charge it, he's done this since I can remember. He's got a newish car now and everyone tells him that it's not necessary these days, but to convince him I need to know actually why not. He's argument is how does he know it's not going to go flat, if anyone can give me a simple answer so I can pass onto him. battery

Answer 1

Batteries are more reliable nowadays, alternator regulators have improved, cars start much quicker with injection and put less load on the battery and overcharging and consequent water loss are things of the past, I started in the Motor trade in the early 70s and topping up batteries was a part of every service, but then there were tiny alternators and Dynamos and batteries were constantly charging and discharging.
Your dad may well wreck the battery by overcharging it, by using an old charger with no regulator capble of delivering 15 plus volts, The battery may well gass, lose water, the acid gets too strong and attacks the plates, and the exposed area of the plates will sulphate. and become useless
The ECU wont like being disconnected and the Radio will probably never work again. Connect a sealed 12 volt Motorbike or Burgler Alarm Battery to the F.A.G. lighter socket before disconnecting the main battery to avoid this, but insulate the dangling positive lead to avoid shorts, why a sealed battery, so you dont burn acid holes in the carpets.

Answer 2

There are two possibilities: 1.) The battery has started to short internally, which means it is time to get a new battery. or 2.) There is a small ground in the positive side of the wiring system, which slowly drains the battery when the alternator is off. The way to test for the latter is to dosconnect the positive cable from the battery, and, using a multimeter set to check resistance, check between the positive cable and the frame of the car. If there is a ground (Usually a worn spot in some wire's insulation) you will know immediately. If that is the case, then you will obviously have to trace down the spot that is grounded, good luck. The interim remedy is to disconnect the battery every time the car is stopped. If there is no ground detected, then it is the battery, go get a new one.

Answer 3

Modern car batteries are much better than the old types, being fully sealed and with advanced metals in the plates, also modern car electrical systems can keep up with heavy loads and still keep the battery fully charged. The only time you would need to recharge the battery out of the car would be if you left an interior light on for a few days, or similar which would flatten it. My car is now 10 years old and I have never charged it with a charger, though the battery was replaced about 3 years ago.

Answer 4

The car's alternator charges the battery every time the engine runs.

I wouldn't worry too much about keeping the battery charged. Most batteries come with a prorated warranty. I have found that the price of a battery is about $1 per month. So if my battery dies 2 years before its warranty expires, I get a $24 credit on the next battery for the 24 months of warranty left.

That's why I buy batteries with the longest life. It basically costs the same per month, I have to get the battery replaced less often, and it is usually a more powerful battery, which helps start the car much better in extremely cold weather.

Answer 5

Car batteries are charged every time the engine is running. Its one of a couple of good reasons to go on a long drive every now and then, and not just short trips to the shops.

As the engine turns over, it turns the alternator which charges the battery automatically. When you consider all the items that people have in their cars these days, its a good idea or you'd soon have a flat battery!

Answer 6

Because your Dad grew up in a time when cars had a dynamo and not an alternator,And he still remembers the winter days when the car did not start.
The old style dynamo had a mechanical regulator to regulate the charging process ,This system had its pitfalls, Full charging was only obtainable at high revs.
A Alternator on the other hand is electronically regulated and will give a full charge with just a Small increase in engine revs.
Battery efficiency has also increased .

Answer 7

If the car is driven regularly the battery should not go flat, even in cold weather, unless the car has a faulty charging system. If however the car is stored for an extended period of time, then the battery would require charging periodically.

Answer 8

All above answers are true, but also another good reason for not removing the battery is that new cars use "learning" ECU's so as to optimise the cars fueling system. If your dad removes the battery chances are the ECU will loose the settings that it has learned and next time you connect the battery and start the car it will not run correctly until the ECU has once again optimised the fuelling system. Usually to optimise the ECU again you need to drive on various roads at different speeds and acceleration so as the ECU learns the fuel/air ratio to exhaust gas emmisions ratio so it will once again be at an optmum setting.

Answer 9

Aaaah! The good old days of 6 volt electrics, and a dynamo. An electrical system that could barely out-power a glow worm.

Tell dad that it isn't necessary anymore, and, in fact, could be injurious to the car, and battery if he charges it incorrectly, or loses the codes and memories of the car's electrical system.

Alternators, batteries with calcium technology, silver plates, recombinant electrolytes, deep-cyclers, high CCA ratings. All wonderful stuff, tell him to sit down and have a beer instead.

Answer 10

When the dynamo could not produce enough power to run the engine and the lights in Winter the battery gradually lost charge. So people charged their batteries.
Now with alternators enough power is produced to power all those fancy ancillaries in a car even at slow engine speeds. So no need to charge a battery.
RoyS.