Any use in periodically charging a car battery to full with a charger? Assuming a car's electrical system is running fine.
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Any use in periodically charging a car battery?
- Thread starter byez
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I've been known to do it if the vehicle as sat for a month or more ( trickly charge overnight). I think it is totally unecessary for a daily driver in good condition. JMO Ed
NO. Most alts keep most batteries in a slightly overgharge state to begin with.
Bob
Bob
During daily use with a good charging system...no.
waste of time.
long term storage would be beneficial to use a trickle charger. Daily use vehicles do not need any additional charge.
long term storage would be beneficial to use a trickle charger. Daily use vehicles do not need any additional charge.
Originally Posted By: byez
Any use in periodically charging a car battery to full with a charger? Assuming a car's electrical system is running fine.
You worry too much byez for your vehicle's charging system is charging fine and your run your system regularly so that your battery is getting charged properly, there's absolutely zero need for "topping up" with a trickle charger.
Q.
Any use in periodically charging a car battery to full with a charger? Assuming a car's electrical system is running fine.
You worry too much byez for your vehicle's charging system is charging fine and your run your system regularly so that your battery is getting charged properly, there's absolutely zero need for "topping up" with a trickle charger.
Q.
No, you don't need to charge it, but you can benefit greatly from a battery desulphator. It's like a trickle charger but it sends pulses of high frequency AC through your battery to remove the sulphation (white stuff) on the lead plates. Battery sulphation is what eventually kills almost all lead acid batteries, and it's slowly forming inside your battery right now as you read this.
I use something called a "Battery Minder" to do this. I plug it into my truck whenever it's going to sit for a few days, one night isn't long enough to do anything. I have actually fixed more than one completely useless battery with this desulphator. The same company (see vdcelectronics.com) sells an onboard desulphator that you install in your vehicle and works as you drive.
I use something called a "Battery Minder" to do this. I plug it into my truck whenever it's going to sit for a few days, one night isn't long enough to do anything. I have actually fixed more than one completely useless battery with this desulphator. The same company (see vdcelectronics.com) sells an onboard desulphator that you install in your vehicle and works as you drive.
Originally Posted By: SecondMonkey
I use something called a "Battery Minder" to do this. I plug it into my truck whenever it's going to sit for a few days, one night isn't long enough to do anything. I have actually fixed more than one completely useless battery with this desulphator. The same company (see vdcelectronics.com) sells an onboard desulphator that you install in your vehicle and works as you drive.
Doesn't Battery Minder just charge a battery? I don't know if it's a desulphator.
I use something called a "Battery Minder" to do this. I plug it into my truck whenever it's going to sit for a few days, one night isn't long enough to do anything. I have actually fixed more than one completely useless battery with this desulphator. The same company (see vdcelectronics.com) sells an onboard desulphator that you install in your vehicle and works as you drive.
Doesn't Battery Minder just charge a battery? I don't know if it's a desulphator.
Originally Posted By: daves66nova
Doesn't Battery Minder just charge a battery? I don't know if it's a desulphator.
No, it's a desulphator too, and a very good one at that. I need to buy another 2 or 3 of them, the one I have is working overtime desulphating all the batteries I own!
Doesn't Battery Minder just charge a battery? I don't know if it's a desulphator.
No, it's a desulphator too, and a very good one at that. I need to buy another 2 or 3 of them, the one I have is working overtime desulphating all the batteries I own!
JHZR2
Staff member
I dont see a real benefit - my mother's car is used for five block commutes, year round, and yet as a 1997 model still has the original battery - 97 plymouth breeze with 110k miles.
I have found, however, that if I put a battery charger on the battery say, right after getting home from work, that the battery charger will provide some current for some time - 30 min to an hour usually, before claiming that the battery is full. So it appears that the alternator max full level is different from that of a battery charger, FWIW.
For batteries that sit, it is beneficial, IMO. Even if just sitting for a month or weeks. ALternators arent designed to bulk charge batteries, so youre better off keeping them nearly full all the time... less wear on the alt, less fuel use on the engine (load), and less chance of a premature battery failure. IMO.
JMH
JMH
I have found, however, that if I put a battery charger on the battery say, right after getting home from work, that the battery charger will provide some current for some time - 30 min to an hour usually, before claiming that the battery is full. So it appears that the alternator max full level is different from that of a battery charger, FWIW.
For batteries that sit, it is beneficial, IMO. Even if just sitting for a month or weeks. ALternators arent designed to bulk charge batteries, so youre better off keeping them nearly full all the time... less wear on the alt, less fuel use on the engine (load), and less chance of a premature battery failure. IMO.
JMH
JMH
I tried a Pulse Tech desulphator hoping for longer battery life. It did appear to change the battery but the battery didn't last longer. Typically a battery is destroyed in two deep discharges. My new battery with all its sulfation removed was destroyed in a single deep discharge, thanks to a malfunctioning brake pedal switch.
I no longer use the PulseTech since it is unlikely and unnecessary to extend the already good 10 year life of a battery and the AM radio noise is quite irritating. The only way to get batteries to last a long time is to keep them from discharging and the aftermarket devices I tried were too poorly designed to actually work.
Auto companies implementing computer control of the interior lights is what did the trick. I can now leave the door, trunk, glovebox, and cigarette lighter open without losing the battery.
Batteries that sit should not use a standard battery charger continuously since non automatic chargers improve charge times by slightly overcharging. Put your ear on the battery when it is at max charge and listen to the life bubble out. There are special chargers for that.
Harbor Freight Item: 42292 AUTOMATIC BATTERY FLOAT CHARGER
Alternators do not overcharge batteries because there is sufficient load from the rest of the car to keep the voltage down. An alternator without the rest of the car as a power sink probably would overcharge. Even a couple of amps from a single light is enough.
Battery chargers are fine but shouldn't be used when the alternator is functioning properly. Batteries charged by alternators last 10 years or more which means that alternators are excellent battery chargers. I charge dead batteries and batteries on cars being serviced that are using power but can't run with a battery charger. I put a battery charger on a car if it doesn't start and needs a lot of cranking to figure out why. Don't leave a non automatic charger unattended.
I no longer use the PulseTech since it is unlikely and unnecessary to extend the already good 10 year life of a battery and the AM radio noise is quite irritating. The only way to get batteries to last a long time is to keep them from discharging and the aftermarket devices I tried were too poorly designed to actually work.
Auto companies implementing computer control of the interior lights is what did the trick. I can now leave the door, trunk, glovebox, and cigarette lighter open without losing the battery.
Batteries that sit should not use a standard battery charger continuously since non automatic chargers improve charge times by slightly overcharging. Put your ear on the battery when it is at max charge and listen to the life bubble out. There are special chargers for that.
Harbor Freight Item: 42292 AUTOMATIC BATTERY FLOAT CHARGER
Alternators do not overcharge batteries because there is sufficient load from the rest of the car to keep the voltage down. An alternator without the rest of the car as a power sink probably would overcharge. Even a couple of amps from a single light is enough.
Battery chargers are fine but shouldn't be used when the alternator is functioning properly. Batteries charged by alternators last 10 years or more which means that alternators are excellent battery chargers. I charge dead batteries and batteries on cars being serviced that are using power but can't run with a battery charger. I put a battery charger on a car if it doesn't start and needs a lot of cranking to figure out why. Don't leave a non automatic charger unattended.
Since it takes about 7-10 miles for an alt to charge a battery after a start, it would make sense to charge a battery that is only being driven for short trips. This will make the battery and the alternator last longer. Why the alt? The altr is not continuously trying to charge the battery. A battery minder like a Battery Tender or Ctek will trickle charge the battery , then shut off the charger once it senses the battery has been charged.
I use an automatic charger continuously on batteries in vehicles that are not used very often. I believe it makes those batteries last significantly longer.
Originally Posted By: Jim Spahr
Since it takes about 7-10 miles for an alt to charge a battery after a start
If my starter takes around 200 amps for four seconds to turn the engine over, I expect my 100 amp alt to recharge the battery within 30 seconds.... including inefficiencies like other electrical loads and time spent at idle producing ~40A.
Regulated alternators are basically float chargers. If your battery is 50% charged its internal resistance is low and it could easily absorb tons of amps from the alt, maybe 20 or so, and get up to 90% charge pretty quickly. Yet at 50% charge will still start the car.
Incidentally alt regulators have a temp sensor and put out a touch extra voltage when cold-- this little extra spike helps top off the battery in a hurry and replace what was "borrowed" for starting. Who knows, this spike might also work as a poor man's desulfator.
Since it takes about 7-10 miles for an alt to charge a battery after a start
If my starter takes around 200 amps for four seconds to turn the engine over, I expect my 100 amp alt to recharge the battery within 30 seconds.... including inefficiencies like other electrical loads and time spent at idle producing ~40A.
Regulated alternators are basically float chargers. If your battery is 50% charged its internal resistance is low and it could easily absorb tons of amps from the alt, maybe 20 or so, and get up to 90% charge pretty quickly. Yet at 50% charge will still start the car.
Incidentally alt regulators have a temp sensor and put out a touch extra voltage when cold-- this little extra spike helps top off the battery in a hurry and replace what was "borrowed" for starting. Who knows, this spike might also work as a poor man's desulfator.
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