I've always try to place a new battery on a charger/tender for about 24 hours before install/use, just to top them off, needed or not. Just habit I guess because I don't remember when & why I started doing it.
charging a new replacement battery before install.
- Thread starter james1950
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When I install a new battery I always put my 10-amp charger on it for roughly an hour before connecting the cables. I worked at a auto parts/service shop in the early '90s, and I recall one of the mechanics telling me that one should always make sure a battery is charged before connecting the cables. He claimed that connecting a discharged battery can result in frying the diode bridge in the alternator. Not sure if that is just folklore or whatever, but it's no big deal to connect a battery charger just to be safe.
I always charge a new battery with a taper charger before installation. When the charging curre3nt drops to 1 ampere or less, it is good to go. Ed
Originally Posted By: HerrStig
It doesn't matter to an alternator if it's producing 50 amps to power everything in the car or puttting 50 amps into the battery. It "doesn't know the difference".
Sure, but when you start a car on a discharged battery, the amp has to produce the regular amps to power everything PLUS extra to charge the battery. And depending on the amount of discharge, we could be talking about some serious extra amps of load. This difference is certainly seen as an extra load on the alternator and extra load produces extra heat and alternators, just like many mechanical devices, don't like to be overheated.
It doesn't matter to an alternator if it's producing 50 amps to power everything in the car or puttting 50 amps into the battery. It "doesn't know the difference".
Sure, but when you start a car on a discharged battery, the amp has to produce the regular amps to power everything PLUS extra to charge the battery. And depending on the amount of discharge, we could be talking about some serious extra amps of load. This difference is certainly seen as an extra load on the alternator and extra load produces extra heat and alternators, just like many mechanical devices, don't like to be overheated.
Battery manufactures warn about charging at over 10 amperes and suggest charging at 2-4 amps for long battery life. I think that says it all-pre-charge at a low rate before installing unless it is really important not to. ed
I always install them in the parking lot and give up the core right there and get back on the road. Can't really charge it. Just make sure the date code is ok and hope for the best.
I put mine on a 2 amp trickle charger for a few hours and when the charge meter falls to zero it's ready to go.
Do you know how sometimes you are on other forums and they start discussing oils, and from being a member here for so long, you realize the many/most of the posters on the other forum are fairly clueless and promoting grandpa's incorrect folklore about oil? Sure a few post some truths, but most post incorrect opinions?
Lead Acid batteries, if given the option, would want to live their life 100% fully charged at all times.
A battery can self discharge 15% a month sitting on the shelf. These rates vary among different batteries and the temperatures they sit at.
The Alternator is NOT very good at returning a depleted battery to 100% State of charge. It takes a long time at voltages in the 14.4+ range for the battery to get from 95% to 100%. Think Hours, no matter how big your alternator, no matter its ratings, no matter how shiny or new it is. The lower the voltage the longer it will take, and argueably low voltages in some cases will never fully charge a battery that has been abused. High amps and at the end of the charge, high voltages are needed in some cases on chronically undercharged batteries
The only way to force a battery to return to maximum specific gravity is with higher electrical pressure, (higher voltage), and generally the High 14s is as high as they should be pushed. high 14's are called acceptance or Absorption voltages, as it takes long times at these voltages to return the electrolyte to maximum density.
Shoehorning in the maximum possible charge into the battery takes hours. On Starting batteries cycled below 90%, on marine batteries cycled below 80% and on Deep cycle batteries cycled below 50%, the more important it is to battery longevity to be returned to a true 100% regularly, and as promptly as possible after a discharge.
Most fully charged car starting batteries today are depleted ~0.005% when starting a car engine, and yet after this tiny depletion, they will suck up 30 to 50 amps from the alternator, briefly, before these amps get the battery voltage into the 14's, then the amps required to hold this 14.x level drops and drops and drops, and then the voltage regulator decides enough is enough and likely drops voltage into the mid to high 13's.
Making sure your battery is indeed fully charged at all times, is wise, if one really cares about getting a maximum lifespan from their battery.
Not doing so will likely never be noticed by the person who does not. Batteries are rented. they fail, they get replaced, and this is all some ever need to know. If this is you, bravo, well done, there are certainly more important things to stress about.
But the person who drains their battery, engine off, and believes the alternator will nearly instantly, and fully charge the battery, is unwise, and will get a poor lifespan from the battery, and blame the battery, when all along it was their misconceptions about how effective an alternator is, and what a battery can or cannot accept.
Nitpicking details here. Do as you please with your battery, but if you want to get maximum lifespan from it, regularly ensuring that it is indeed 100% fully charged, and stays close to that level of charge, will yield the best lifespan.
So starting out at a known 100% level is Wise. Wiser would be the person who can apply high 14's, perhaps low 15 voltages until amps fall to below 0.5 or less, then take and record specific gravity reading with a glass float turkey baster style hydrometer, and do so every so often, charging until Specific gravity reverts to that initial reading, which can be anywhere between 1.275 and 1.310, depending on the battery and the climate it was made for. In general hotter climates have lower maximum specific gravities.
Don't fear applying high amperages into a depleted battery. It is more important to get it to full charge, than it is to give it the low and slow treatment which might not get it anywhere near full charge before the charger is disconnected.
A vehicle which needs a jump start will likely Max out the alternator for a good half hour, with amperages in the 50 to 60 amps range before battery voltage climbs into the mid 14's.
Yes this is hard on an alternator, especially in an idling vehicle with little underhood airflow.
Reman'd alternators need to have the battery fully recharged before starting the vehicle as the unbroken in brushes cannot handle the extreme current demands of a depleted battery.
Jump started vehicles should have a grid powered charger applied as soon as possible after the jump started vehicle gets the driver home, and left on until the battery is indeed fully charged, and a 2 amp trickle charger applied for 8 hours is NOT enough.
Automatic chargers hooked up quickly after arring home might see surface charge from the alternator from the drive home, and decide the battery does not need to go into the 14's.
Battery abusers drive up the price of batteries and reduce the timespan of offered warranty.
Many battery chargers that indicate a battery is fully charged, are downright liars. Checking Specific gravity battery polygraph. Seeing little amps flowing into the battery at high voltages is another good indicator. Automatic battery chargers are automatic battery underchargers, as it is safer and lawyer approved to undercharge a battery.
Sometimes trickery is involved in getting an Automatic charger to restart and finish the task it did not perform the first time.( yet indicated it did) Pull battery voltage to below 12.6v with some heavy loads, then restart the charger, on a lower amp setting if available. Might take 4 or 5 times of doing this before specific gravity maxes out, but it is possible it will not, and only another week left at float/ maintenance voltages will do so.
Sometimes it will take a manual charger or power supply which can bring the battery to 16 volts before maximum Specific gravity is reached., but these rather extreme voltages are only to be induced after the battery has spent at least 2 hours in the high 14 range, and 16V is to be stopped after electrolyte gets no denser, or approaches 120F.
There is a whole bunch more to fully charging and maintaining a lead acid battery for maximum service life, than just driving or slapping a trickle charger on it after a jumpstart was required.
Lead Acid batteries, if given the option, would want to live their life 100% fully charged at all times.
A battery can self discharge 15% a month sitting on the shelf. These rates vary among different batteries and the temperatures they sit at.
The Alternator is NOT very good at returning a depleted battery to 100% State of charge. It takes a long time at voltages in the 14.4+ range for the battery to get from 95% to 100%. Think Hours, no matter how big your alternator, no matter its ratings, no matter how shiny or new it is. The lower the voltage the longer it will take, and argueably low voltages in some cases will never fully charge a battery that has been abused. High amps and at the end of the charge, high voltages are needed in some cases on chronically undercharged batteries
The only way to force a battery to return to maximum specific gravity is with higher electrical pressure, (higher voltage), and generally the High 14s is as high as they should be pushed. high 14's are called acceptance or Absorption voltages, as it takes long times at these voltages to return the electrolyte to maximum density.
Shoehorning in the maximum possible charge into the battery takes hours. On Starting batteries cycled below 90%, on marine batteries cycled below 80% and on Deep cycle batteries cycled below 50%, the more important it is to battery longevity to be returned to a true 100% regularly, and as promptly as possible after a discharge.
Most fully charged car starting batteries today are depleted ~0.005% when starting a car engine, and yet after this tiny depletion, they will suck up 30 to 50 amps from the alternator, briefly, before these amps get the battery voltage into the 14's, then the amps required to hold this 14.x level drops and drops and drops, and then the voltage regulator decides enough is enough and likely drops voltage into the mid to high 13's.
Making sure your battery is indeed fully charged at all times, is wise, if one really cares about getting a maximum lifespan from their battery.
Not doing so will likely never be noticed by the person who does not. Batteries are rented. they fail, they get replaced, and this is all some ever need to know. If this is you, bravo, well done, there are certainly more important things to stress about.
But the person who drains their battery, engine off, and believes the alternator will nearly instantly, and fully charge the battery, is unwise, and will get a poor lifespan from the battery, and blame the battery, when all along it was their misconceptions about how effective an alternator is, and what a battery can or cannot accept.
Nitpicking details here. Do as you please with your battery, but if you want to get maximum lifespan from it, regularly ensuring that it is indeed 100% fully charged, and stays close to that level of charge, will yield the best lifespan.
So starting out at a known 100% level is Wise. Wiser would be the person who can apply high 14's, perhaps low 15 voltages until amps fall to below 0.5 or less, then take and record specific gravity reading with a glass float turkey baster style hydrometer, and do so every so often, charging until Specific gravity reverts to that initial reading, which can be anywhere between 1.275 and 1.310, depending on the battery and the climate it was made for. In general hotter climates have lower maximum specific gravities.
Don't fear applying high amperages into a depleted battery. It is more important to get it to full charge, than it is to give it the low and slow treatment which might not get it anywhere near full charge before the charger is disconnected.
A vehicle which needs a jump start will likely Max out the alternator for a good half hour, with amperages in the 50 to 60 amps range before battery voltage climbs into the mid 14's.
Yes this is hard on an alternator, especially in an idling vehicle with little underhood airflow.
Reman'd alternators need to have the battery fully recharged before starting the vehicle as the unbroken in brushes cannot handle the extreme current demands of a depleted battery.
Jump started vehicles should have a grid powered charger applied as soon as possible after the jump started vehicle gets the driver home, and left on until the battery is indeed fully charged, and a 2 amp trickle charger applied for 8 hours is NOT enough.
Automatic chargers hooked up quickly after arring home might see surface charge from the alternator from the drive home, and decide the battery does not need to go into the 14's.
Battery abusers drive up the price of batteries and reduce the timespan of offered warranty.
Many battery chargers that indicate a battery is fully charged, are downright liars. Checking Specific gravity battery polygraph. Seeing little amps flowing into the battery at high voltages is another good indicator. Automatic battery chargers are automatic battery underchargers, as it is safer and lawyer approved to undercharge a battery.
Sometimes trickery is involved in getting an Automatic charger to restart and finish the task it did not perform the first time.( yet indicated it did) Pull battery voltage to below 12.6v with some heavy loads, then restart the charger, on a lower amp setting if available. Might take 4 or 5 times of doing this before specific gravity maxes out, but it is possible it will not, and only another week left at float/ maintenance voltages will do so.
Sometimes it will take a manual charger or power supply which can bring the battery to 16 volts before maximum Specific gravity is reached., but these rather extreme voltages are only to be induced after the battery has spent at least 2 hours in the high 14 range, and 16V is to be stopped after electrolyte gets no denser, or approaches 120F.
There is a whole bunch more to fully charging and maintaining a lead acid battery for maximum service life, than just driving or slapping a trickle charger on it after a jumpstart was required.
I am not sure it makes any difference, but when I put a set of new batteries in my semi truck, I always fully charge them after the install. I have a Xantrex inverter / charger on board the truck and I just plug it into shore power after I complete the install and let it fully charge up the batteries. But then, every weekend when I bring the truck home, it gets hooked up to shore power for the exact same reason, and that also there is a fridge and other stuff using power even while the truck is shut off. I seem to get an appreciable longer life out of a set of truck batteries by doing the plug in thing every weekend when the truck comes in. Just seemed prudent to plug it in and have the fresh batteries up to full charge before heading out. As was stated, typical lead acid batteries love to live their life fully charged.
Originally Posted By: wrcsixeight
Do you know how sometimes you are on other forums and they start discussing oils, and from being a member here for so long, you realize the many/most of the posters on the other forum are fairly clueless and promoting grandpa's incorrect folklore about oil? Sure a few post some truths, but most post incorrect opinions?
Lead Acid batteries, if given the option, would want to live their life 100% fully charged at all times.
A battery can self discharge 15% a month sitting on the shelf. These rates vary among different batteries and the temperatures they sit at.
The Alternator is NOT very good at returning a depleted battery to 100% State of charge. It takes a long time at voltages in the 14.4+ range for the battery to get from 95% to 100%. Think Hours, no matter how big your alternator, no matter its ratings, no matter how shiny or new it is. The lower the voltage the longer it will take, and argueably low voltages in some cases will never fully charge a battery that has been abused. High amps and at the end of the charge, high voltages are needed in some cases on chronically undercharged batteries
The only way to force a battery to return to maximum specific gravity is with higher electrical pressure, (higher voltage), and generally the High 14s is as high as they should be pushed. high 14's are called acceptance or Absorption voltages, as it takes long times at these voltages to return the electrolyte to maximum density.
Shoehorning in the maximum possible charge into the battery takes hours. On Starting batteries cycled below 90%, on marine batteries cycled below 80% and on Deep cycle batteries cycled below 50%, the more important it is to battery longevity to be returned to a true 100% regularly, and as promptly as possible after a discharge.
Most fully charged car starting batteries today are depleted ~0.005% when starting a car engine, and yet after this tiny depletion, they will suck up 30 to 50 amps from the alternator, briefly, before these amps get the battery voltage into the 14's, then the amps required to hold this 14.x level drops and drops and drops, and then the voltage regulator decides enough is enough and likely drops voltage into the mid to high 13's.
Making sure your battery is indeed fully charged at all times, is wise, if one really cares about getting a maximum lifespan from their battery.
Not doing so will likely never be noticed by the person who does not. Batteries are rented. they fail, they get replaced, and this is all some ever need to know. If this is you, bravo, well done, there are certainly more important things to stress about.
But the person who drains their battery, engine off, and believes the alternator will nearly instantly, and fully charge the battery, is unwise, and will get a poor lifespan from the battery, and blame the battery, when all along it was their misconceptions about how effective an alternator is, and what a battery can or cannot accept.
Nitpicking details here. Do as you please with your battery, but if you want to get maximum lifespan from it, regularly ensuring that it is indeed 100% fully charged, and stays close to that level of charge, will yield the best lifespan.
So starting out at a known 100% level is Wise. Wiser would be the person who can apply high 14's, perhaps low 15 voltages until amps fall to below 0.5 or less, then take and record specific gravity reading with a glass float turkey baster style hydrometer, and do so every so often, charging until Specific gravity reverts to that initial reading, which can be anywhere between 1.275 and 1.310, depending on the battery and the climate it was made for. In general hotter climates have lower maximum specific gravities.
Don't fear applying high amperages into a depleted battery. It is more important to get it to full charge, than it is to give it the low and slow treatment which might not get it anywhere near full charge before the charger is disconnected.
A vehicle which needs a jump start will likely Max out the alternator for a good half hour, with amperages in the 50 to 60 amps range before battery voltage climbs into the mid 14's.
Yes this is hard on an alternator, especially in an idling vehicle with little underhood airflow.
Reman'd alternators need to have the battery fully recharged before starting the vehicle as the unbroken in brushes cannot handle the extreme current demands of a depleted battery.
Jump started vehicles should have a grid powered charger applied as soon as possible after the jump started vehicle gets the driver home, and left on until the battery is indeed fully charged, and a 2 amp trickle charger applied for 8 hours is NOT enough.
Automatic chargers hooked up quickly after arring home might see surface charge from the alternator from the drive home, and decide the battery does not need to go into the 14's.
Battery abusers drive up the price of batteries and reduce the timespan of offered warranty.
Many battery chargers that indicate a battery is fully charged, are downright liars. Checking Specific gravity battery polygraph. Seeing little amps flowing into the battery at high voltages is another good indicator. Automatic battery chargers are automatic battery underchargers, as it is safer and lawyer approved to undercharge a battery.
Sometimes trickery is involved in getting an Automatic charger to restart and finish the task it did not perform the first time.( yet indicated it did) Pull battery voltage to below 12.6v with some heavy loads, then restart the charger, on a lower amp setting if available. Might take 4 or 5 times of doing this before specific gravity maxes out, but it is possible it will not, and only another week left at float/ maintenance voltages will do so.
Sometimes it will take a manual charger or power supply which can bring the battery to 16 volts before maximum Specific gravity is reached., but these rather extreme voltages are only to be induced after the battery has spent at least 2 hours in the high 14 range, and 16V is to be stopped after electrolyte gets no denser, or approaches 120F.
There is a whole bunch more to fully charging and maintaining a lead acid battery for maximum service life, than just driving or slapping a trickle charger on it after a jumpstart was required.
Do you know how sometimes you are on other forums and they start discussing oils, and from being a member here for so long, you realize the many/most of the posters on the other forum are fairly clueless and promoting grandpa's incorrect folklore about oil? Sure a few post some truths, but most post incorrect opinions?
Lead Acid batteries, if given the option, would want to live their life 100% fully charged at all times.
A battery can self discharge 15% a month sitting on the shelf. These rates vary among different batteries and the temperatures they sit at.
The Alternator is NOT very good at returning a depleted battery to 100% State of charge. It takes a long time at voltages in the 14.4+ range for the battery to get from 95% to 100%. Think Hours, no matter how big your alternator, no matter its ratings, no matter how shiny or new it is. The lower the voltage the longer it will take, and argueably low voltages in some cases will never fully charge a battery that has been abused. High amps and at the end of the charge, high voltages are needed in some cases on chronically undercharged batteries
The only way to force a battery to return to maximum specific gravity is with higher electrical pressure, (higher voltage), and generally the High 14s is as high as they should be pushed. high 14's are called acceptance or Absorption voltages, as it takes long times at these voltages to return the electrolyte to maximum density.
Shoehorning in the maximum possible charge into the battery takes hours. On Starting batteries cycled below 90%, on marine batteries cycled below 80% and on Deep cycle batteries cycled below 50%, the more important it is to battery longevity to be returned to a true 100% regularly, and as promptly as possible after a discharge.
Most fully charged car starting batteries today are depleted ~0.005% when starting a car engine, and yet after this tiny depletion, they will suck up 30 to 50 amps from the alternator, briefly, before these amps get the battery voltage into the 14's, then the amps required to hold this 14.x level drops and drops and drops, and then the voltage regulator decides enough is enough and likely drops voltage into the mid to high 13's.
Making sure your battery is indeed fully charged at all times, is wise, if one really cares about getting a maximum lifespan from their battery.
Not doing so will likely never be noticed by the person who does not. Batteries are rented. they fail, they get replaced, and this is all some ever need to know. If this is you, bravo, well done, there are certainly more important things to stress about.
But the person who drains their battery, engine off, and believes the alternator will nearly instantly, and fully charge the battery, is unwise, and will get a poor lifespan from the battery, and blame the battery, when all along it was their misconceptions about how effective an alternator is, and what a battery can or cannot accept.
Nitpicking details here. Do as you please with your battery, but if you want to get maximum lifespan from it, regularly ensuring that it is indeed 100% fully charged, and stays close to that level of charge, will yield the best lifespan.
So starting out at a known 100% level is Wise. Wiser would be the person who can apply high 14's, perhaps low 15 voltages until amps fall to below 0.5 or less, then take and record specific gravity reading with a glass float turkey baster style hydrometer, and do so every so often, charging until Specific gravity reverts to that initial reading, which can be anywhere between 1.275 and 1.310, depending on the battery and the climate it was made for. In general hotter climates have lower maximum specific gravities.
Don't fear applying high amperages into a depleted battery. It is more important to get it to full charge, than it is to give it the low and slow treatment which might not get it anywhere near full charge before the charger is disconnected.
A vehicle which needs a jump start will likely Max out the alternator for a good half hour, with amperages in the 50 to 60 amps range before battery voltage climbs into the mid 14's.
Yes this is hard on an alternator, especially in an idling vehicle with little underhood airflow.
Reman'd alternators need to have the battery fully recharged before starting the vehicle as the unbroken in brushes cannot handle the extreme current demands of a depleted battery.
Jump started vehicles should have a grid powered charger applied as soon as possible after the jump started vehicle gets the driver home, and left on until the battery is indeed fully charged, and a 2 amp trickle charger applied for 8 hours is NOT enough.
Automatic chargers hooked up quickly after arring home might see surface charge from the alternator from the drive home, and decide the battery does not need to go into the 14's.
Battery abusers drive up the price of batteries and reduce the timespan of offered warranty.
Many battery chargers that indicate a battery is fully charged, are downright liars. Checking Specific gravity battery polygraph. Seeing little amps flowing into the battery at high voltages is another good indicator. Automatic battery chargers are automatic battery underchargers, as it is safer and lawyer approved to undercharge a battery.
Sometimes trickery is involved in getting an Automatic charger to restart and finish the task it did not perform the first time.( yet indicated it did) Pull battery voltage to below 12.6v with some heavy loads, then restart the charger, on a lower amp setting if available. Might take 4 or 5 times of doing this before specific gravity maxes out, but it is possible it will not, and only another week left at float/ maintenance voltages will do so.
Sometimes it will take a manual charger or power supply which can bring the battery to 16 volts before maximum Specific gravity is reached., but these rather extreme voltages are only to be induced after the battery has spent at least 2 hours in the high 14 range, and 16V is to be stopped after electrolyte gets no denser, or approaches 120F.
There is a whole bunch more to fully charging and maintaining a lead acid battery for maximum service life, than just driving or slapping a trickle charger on it after a jumpstart was required.
Originally Posted By: Kory
I know a store that keeps a handful of batteries on tenders so they're 100% fresh "off the rack" so to speak.
Yes, but I do not think this is the norm. Interstate batteries at my Indy are shrink-wrapped across the top.
I know a store that keeps a handful of batteries on tenders so they're 100% fresh "off the rack" so to speak.
Yes, but I do not think this is the norm. Interstate batteries at my Indy are shrink-wrapped across the top.
I drive my car only 2-3 30 minute trips per week, excluding road trips.
So every 3 months I charge it 12 hours or so on a supply set to 14V, then charge 16V for an hour to equalize.
The original battery is entering its 8th winter still going strong.
Last time I bought a new battery I swapped at the store then gave it a long charge when I got home.
So every 3 months I charge it 12 hours or so on a supply set to 14V, then charge 16V for an hour to equalize.
The original battery is entering its 8th winter still going strong.
Last time I bought a new battery I swapped at the store then gave it a long charge when I got home.
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