If my 1996 Jeep has complex regulated voltage control (with battery temperature sensor, too), I don't see why a 2009 Sonata couldn't.
Less than 14 volts while running
- Thread starter Shaman
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That's different story. The battery temperature sensor is just used to avoid overheating issues, but your Jeep lacks the amart voltage regulation, providing higher voltage on deceleration (for inceased charging) and lower voltage on acceleration (for no charging and reduced drag). BMW has been one of the very first inventing this tech in 2007 (as part of so-called "BMW efficient dynamics" along with start-stop) rolling out this from 2007 til 2009/2010 over their European product range. Other manufacturers following this trend quite soon.
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I've put an ammeter that reads charging amperage into, or discharging current out of my battery
I can spin a dial on my dashboard, near that ammeter, and choose voltage.
My TPPL AGM battery has a full charge resting voltage of 13.06v, and Norhtstar specifies an absorption voltage of 14.4 to 14.8v and a float voltage of 13.6v, at 77f.
When I know the battery to be chock full....,
If I choose 13.5v, which is still over the full charge resting voltage, there is a small discharge current from the battery, on the order of ~0.2 amps
If I choose 13.1 volts it is about 0.4 amps draw on the battery.
In theory any voltage holding the battery above its full charge resting voltage, should prevent discharge, but when there are DC loads, this does not hold true.
Simply holding a battery at or even slightly above its fully charged resting voltage, while there are DC loads on the electrical system, AND even though the alternator, in theory, should be powering these loads, well it does not work that way.
The higher the DC loads, and the cooler the battery, the higher the voltage should be to prevent slow discharges of the fully charged battery.
The float voltage needs to be a few tenths above the manufacturer recommended float voltage to prevent battery from slowly discharging when there are DC loads on the system.
The colder the battery, and the higher the DC loads on the vehicles system are, the higher the float voltage needs to be to prevent loads from slowly discharging it.
If some ECU controlled voltage regulator decided to hold my TPPL AGM at 12.7v, I would be sledgehammer swingingly mad.
My OBD1 era ECU chose 13.7 or 14.9v, 98% of the time, before I neutered it and installed an adjustable voltage regulator.
13.7v would charge my well discharged battery at 1/3 the rate of 14.7v, and occassionally if my battery would be fully charged, it would shoot from 13.7 to 14.9 for no reason I could ever determine, other than to just irritate me and ry and cook the battery.
The manipulation of voltage for the sake of incremental improvements in MPG, does not help lead acid batteries live longer, as they always want to be fully charged, not @ ~ 85%.
A fully charged battery cannot accept much amperage even at high voltages, so for the MPG/voltage manipulation strategy to work, the battery needs to be kept in the 80% range, where a computer programmed spike to 14.5v, will have the battery briefly able to accept 25 or more amps from the alternator.
It is said that each 25 amps an alternator generates, eats up 1 engine HP.
Alternators are only 50 to 65% efficient, not including belt losses. so don't come at me with the 745.1 watt thing.
I imagine the voltage manipulation strategies vary among different makes and models.
Just know that it is not about battery health, it is about MPG.
The anal rententive OCD bitoger wanting to get better battery longevity in such a vehicle, would be wise to insure their battery has a chance to occassionally spend time at elevated charge voltages, in the hope to occasionally reach full charge, or as close to this ideal as their grid powered charging sources can attain.
In deep cycling batteries, the hardest thing for a battery, is to start the next discharge cycle before the recharge cycle has been completed. Charge to 89% only, 7 times in a row, and such a battery is much less overall capacity to deliver, not just that 89%, but likely 70% compared to cycle number one.
A PSOC'd battery will act like a significantly smaller less healthy battery, and degrade at a faster rate.
Partial state of charge cycling can quickly destroy a battery's capacity, and besides weight, is the major downfall of all lead acid batteries.
There are attempts to mitigate the negative effects PSOC abuse, with the addition of carbon into the plate paste alloy. IN the Automotive workd these are called 'enhanced' flooded batteries. I think the jury is still out on a majority of them, though Boaters do report the Oasis Firefly to be highly resistant to PSOC abuse.
Generally, a deep cycle is considered taking the battery below 80%, and it seems that many auto makers are trying to keep their batteries in the 80 to 85% range, so their voltage manipulation strategy has a chance to increase their overall fleet CAFE score.
When PSOC cycling occurs, in true deep cycle use, for many days on end, the battery gets petulant, and it will not accept much amperage at high voltage( whereas it would on PSOC cycle number 1) and it will take many times longer for it to reach true full charge, should the charging source apply higher voltages for the timespan required.
Some data on my own batteries, cycled to just below 50%, on cycle one, I can attain true full charge in 6.5 hours, on PSOC cycle number 7 achieving true full charge takes 10.5 hours, getting from 98% to 100% is 2+ of those hours. The more PSOC cycles accumulated, the longer it takes to reach true full charge, as measured by an Ammeter( when holding the battery at absorption voltages) or temperature compensating hydrometer.
Do not believe the green light on any 'smart' charging source, as it only indicates the charger has stopped applying absorption voltage, and the battery is charged enough to start the vehicle.
As the batteries age, and even though they lose overall capacity, the time it takes to reach true full charge from 85% or below, keeps increasing, and nearer their end of life, lesser charge voltages simply cannot bring the battery to full charge no matter how long they are applied.
In a Starting/ lighting/ ignition battery, the PSOC cycling is much lighter duty, and less detrimental than if it were cycled deeper, but lead acid battery lifespans have shortened with modern vehicles that employ such a voltage manipulation strategy in the quest for incremental improvements of MPG, as the expense of the battery.
Do not believe for a second that the modern voltage regulation for mpg strategies, is for the health of the battery.
Intentionally keeping the lead acid battery below 100% state of charge is detrimental to it, to some degree the lower average state of charge it resides, the faster it degrades/loses capacity and CCA.
AGM is a lead acid battery too, the electrolyte is just absorbed in a Glass Matt.
There are many parallels with this voltage manipulation strategy, to the thick vs thin oil / c.a.f.e. arguments, that always arise on this forum.
The major difference is that one cannot easily override their computer controlled voltage regulation.
I had to trick my archaic OBD1 era ECM with a 10 ohm 50 watt resistor, into thinking it was still hooked to an externally regulated alternator, to prevent it from illuminating the check engine light, and I need to prevent 14.7v+ happening for 30+ seconds for it to stay off.
I can spin a dial on my dashboard, near that ammeter, and choose voltage.
My TPPL AGM battery has a full charge resting voltage of 13.06v, and Norhtstar specifies an absorption voltage of 14.4 to 14.8v and a float voltage of 13.6v, at 77f.
When I know the battery to be chock full....,
If I choose 13.5v, which is still over the full charge resting voltage, there is a small discharge current from the battery, on the order of ~0.2 amps
If I choose 13.1 volts it is about 0.4 amps draw on the battery.
In theory any voltage holding the battery above its full charge resting voltage, should prevent discharge, but when there are DC loads, this does not hold true.
Simply holding a battery at or even slightly above its fully charged resting voltage, while there are DC loads on the electrical system, AND even though the alternator, in theory, should be powering these loads, well it does not work that way.
The higher the DC loads, and the cooler the battery, the higher the voltage should be to prevent slow discharges of the fully charged battery.
The float voltage needs to be a few tenths above the manufacturer recommended float voltage to prevent battery from slowly discharging when there are DC loads on the system.
The colder the battery, and the higher the DC loads on the vehicles system are, the higher the float voltage needs to be to prevent loads from slowly discharging it.
If some ECU controlled voltage regulator decided to hold my TPPL AGM at 12.7v, I would be sledgehammer swingingly mad.
My OBD1 era ECU chose 13.7 or 14.9v, 98% of the time, before I neutered it and installed an adjustable voltage regulator.
13.7v would charge my well discharged battery at 1/3 the rate of 14.7v, and occassionally if my battery would be fully charged, it would shoot from 13.7 to 14.9 for no reason I could ever determine, other than to just irritate me and ry and cook the battery.
The manipulation of voltage for the sake of incremental improvements in MPG, does not help lead acid batteries live longer, as they always want to be fully charged, not @ ~ 85%.
A fully charged battery cannot accept much amperage even at high voltages, so for the MPG/voltage manipulation strategy to work, the battery needs to be kept in the 80% range, where a computer programmed spike to 14.5v, will have the battery briefly able to accept 25 or more amps from the alternator.
It is said that each 25 amps an alternator generates, eats up 1 engine HP.
Alternators are only 50 to 65% efficient, not including belt losses. so don't come at me with the 745.1 watt thing.
I imagine the voltage manipulation strategies vary among different makes and models.
Just know that it is not about battery health, it is about MPG.
The anal rententive OCD bitoger wanting to get better battery longevity in such a vehicle, would be wise to insure their battery has a chance to occassionally spend time at elevated charge voltages, in the hope to occasionally reach full charge, or as close to this ideal as their grid powered charging sources can attain.
In deep cycling batteries, the hardest thing for a battery, is to start the next discharge cycle before the recharge cycle has been completed. Charge to 89% only, 7 times in a row, and such a battery is much less overall capacity to deliver, not just that 89%, but likely 70% compared to cycle number one.
A PSOC'd battery will act like a significantly smaller less healthy battery, and degrade at a faster rate.
Partial state of charge cycling can quickly destroy a battery's capacity, and besides weight, is the major downfall of all lead acid batteries.
There are attempts to mitigate the negative effects PSOC abuse, with the addition of carbon into the plate paste alloy. IN the Automotive workd these are called 'enhanced' flooded batteries. I think the jury is still out on a majority of them, though Boaters do report the Oasis Firefly to be highly resistant to PSOC abuse.
Generally, a deep cycle is considered taking the battery below 80%, and it seems that many auto makers are trying to keep their batteries in the 80 to 85% range, so their voltage manipulation strategy has a chance to increase their overall fleet CAFE score.
When PSOC cycling occurs, in true deep cycle use, for many days on end, the battery gets petulant, and it will not accept much amperage at high voltage( whereas it would on PSOC cycle number 1) and it will take many times longer for it to reach true full charge, should the charging source apply higher voltages for the timespan required.
Some data on my own batteries, cycled to just below 50%, on cycle one, I can attain true full charge in 6.5 hours, on PSOC cycle number 7 achieving true full charge takes 10.5 hours, getting from 98% to 100% is 2+ of those hours. The more PSOC cycles accumulated, the longer it takes to reach true full charge, as measured by an Ammeter( when holding the battery at absorption voltages) or temperature compensating hydrometer.
Do not believe the green light on any 'smart' charging source, as it only indicates the charger has stopped applying absorption voltage, and the battery is charged enough to start the vehicle.
As the batteries age, and even though they lose overall capacity, the time it takes to reach true full charge from 85% or below, keeps increasing, and nearer their end of life, lesser charge voltages simply cannot bring the battery to full charge no matter how long they are applied.
In a Starting/ lighting/ ignition battery, the PSOC cycling is much lighter duty, and less detrimental than if it were cycled deeper, but lead acid battery lifespans have shortened with modern vehicles that employ such a voltage manipulation strategy in the quest for incremental improvements of MPG, as the expense of the battery.
Do not believe for a second that the modern voltage regulation for mpg strategies, is for the health of the battery.
Intentionally keeping the lead acid battery below 100% state of charge is detrimental to it, to some degree the lower average state of charge it resides, the faster it degrades/loses capacity and CCA.
AGM is a lead acid battery too, the electrolyte is just absorbed in a Glass Matt.
There are many parallels with this voltage manipulation strategy, to the thick vs thin oil / c.a.f.e. arguments, that always arise on this forum.
The major difference is that one cannot easily override their computer controlled voltage regulation.
I had to trick my archaic OBD1 era ECM with a 10 ohm 50 watt resistor, into thinking it was still hooked to an externally regulated alternator, to prevent it from illuminating the check engine light, and I need to prevent 14.7v+ happening for 30+ seconds for it to stay off.
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