Smart charger vs dumb charger

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Occasionally, I received battery for warranty claims and they are suspected to be good but merely discharged. I'd used smart charger (between ctek and xtreme) to charge until they are 100% according to the charger and sent them back. I check CCA is also good. But sometimes I get the same complains again. Recently, I decided to check the electrolyte after the smart charging and realized that some were still in the poor range, even though it's supposed to "fully charged". Then I continued with the charging using a dumb charger at boost voltage (15.0V) until the current absorption drops to almost zero. After which I measured the electrolyte is now good. It seems to be me, the smart charger are not so smart after all and stopped charging too soon. I'd like the electrolyte to be in the good range, before sending them out, but also I'm afraid that I was overcharging the battery. Any thoughts?
 

kb27

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Originally Posted By: HardbodyLoyalist
What current are you charging at?
Using the dumb charger, it depends on the fixed voltage. The current may start at say 8 amp and then drop all the way down to 1 amp and below during charging.
 

kb27

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Originally Posted By: 901Memphis
Maybe your looking at the wrong smart charger, try a Noco.
I'd like to get a Noco, but smart charger doesn't give me much confidence at this time.
 
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Originally Posted By: kb27
Originally Posted By: 901Memphis
Maybe your looking at the wrong smart charger, try a Noco.
I'd like to get a Noco, but smart charger doesn't give me much confidence at this time.
Not all smart chargers are created equal.
 
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Forgive me the topic drift, but actually how are you supposed to use a float charger, dumb or smart? I do very short haul, low mileage driving, but I drive my car every day. I was told that my battery wasn't in tip top shape at the last maintenance, although they did not try and sell me a new battery. So based on what I saw here, I bought a float charger and put it on my car. Should this be an every day thing? Once a week? what?
 
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Just a guess, but I'd expect the smart charger to have a substantial safety margin built in to avoid boiling the battery. It may very well be slightly undercharging by design. It's also entirely possible that its internal voltmeter is losing its calibration.
 
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Originally Posted By: jimbrewer
Forgive me the topic drift, but actually how are you supposed to use a float charger, dumb or smart? I do very short haul, low mileage driving, but I drive my car every day. I was told that my battery wasn't in tip top shape at the last maintenance, although they did not try and sell me a new battery. So based on what I saw here, I bought a float charger and put it on my car. Should this be an every day thing? Once a week? what?
I think you need to make sure your battery and charging system is working properly. A float charger is not really made to charge a battery but rather keep a battery fully charged. But it will charge a battery at a slow rate of 1 amp. I would suggest you get a 6 to 12 amp smart charger and charge the battery once a week. Could your vehicle have some kind of parasitic battery drain?
 

JHZR2

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a smart charger just implies that it has some current controlled design and logic. Typically it's a constant current to a certain point, then constant voltage until the current flow hits another point. So a smart charger, while being smart about things like reverse polarity, not pummeling excess charge into a full battery, etc., may be mistaken on a high impedance battery when said high impedance causes voltage to ratchet up to a limit and current to still be really low. An equalization charge, which only some smart chargers can/will do (a good thing not to do because it causes excess gassing and corrosion) requires a high charge voltage, and can be good in some cases. Remember that you're dealing with a chemically reacting system with a lot of different degradation modes, so it isn't one size fits all...
 
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I'd be looking at the alternator, regulator (usually built into the alternator now,) brushes, and the battery and alternator grounds. Make sure all connections are clean. Unless your alternator is weak, it is sized by the builder to work for any kind of driving. The battery (negative terminal) ground is usually hidden somewhere and can get pretty growdy from battery weep running sown the cable.
 
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