battery charger question

[hardwater fisherman]

i bought a new charger for use on my marine battery. it is just a standard 12 volt charger. it has a 2amp and 10 amp charge. i would assume the 10amp setting would charge faster but it does not. after a day of boating i put the charger on the battery and when i selected 10amps it showed the battery as half charged. and it took around 10 hrs to give a full charge. then the next time i used the battery i selected 10 amps and it showed around half charged again. then i switched it to 2amps and it showed 3/4 charged. and it fully charged in around 5 hrs when left on the 2amp setting. does this seem correct?

 

[UncleWillie]

Re: battery charger question

2 or 10 amps is the Maximum Current the charger will deliver in each setting. NOT the amount it WILL deliver.

10 amps will be too much for a 12 volt motorcycle battery, but fine for an auto/boat sized battery.
The charger will attempt to produce ~14.5 volts and the battery will absorb the max current 2/10a until it reaches that voltage.
After that point the voltage will remain constant at ~14.5v but the current will go down.
When set at 10 amps, the last hours of the charge may very well be Less Than 2 amps.
It is how the physics of the Battery Chemistry works.

A 10 amp charger will charge a very depleted auto/boat battery faster than a 2 amp charger, but not anywhere near 5 times faster.
If the battery does not need a significant charge, you may not notice a significant difference between the 2 and 10 amp settings.

The percentage of charge displayed by the charger is a marketing gimmick. Do not put a lot of faith in the indication.

What is the MAKE and MODEL of the Charger you are using?

 

[hardwater fisherman]

Re: battery charger question

it is the cheapest motomaster charger from canadian tire and probably made in china. my only concern is that the battery is a few years old now but it is still quite strong and i just want to get the most out of it. my last charger was stolen right out of my driveway when i went inside for two minutes.

 

[RogersJetboat454]

Re: battery charger question

it is the cheapest motomaster charger from canadian tire and probably made in china. my only concern is that the battery is a few years old now but it is still quite strong and i just want to get the most out of it. my last charger was stolen right out of my driveway when i went inside for two minutes.

Charge the battery as quickly as possible after you run it down, and it should last a good while. A depleted battery left a long time with out a charge will have its life shortened every time it's left that way.

What is this battery being used for? Trolling, starting, house (lights, radios etc)?

 

[hardwater fisherman]

Re: battery charger question

i run a fishfinder and an electric motor and if dark my lights. in 2 yrs only twice has the battery ran low to where i could not run the electric motor without the sonar going off. when i stopped using the electric motor the sonar ran for hours after. i just started up my 4hp johnson to finish the day.

 

[UncleWillie]

Re: battery charger question

it is the cheapest motomaster charger from canadian tire and probably made in china...

Is THIS your Charger?

 

[hardwater fisherman]

Re: battery charger question

yes thats the one i have.

 

[UncleWillie]

Re: battery charger question

That style is generally considered a Manual Charger.
Except your model does say it will shut OFF after charging.

The meter is a current meter and the % of charge reading is Wishful Marketing.
The 0 to 12 numbers are all that matters
If the battery is small enough to hold in one hand at arms length. Charge at 2 Amps.
If it is Automotive Sized. Charge at 10 Amps.

The meter will initially indicate a high current and slowly reduce to almost nothing.
When the "Full Charge" Light comes ON, Your Done.

 

[hardwater fisherman]

Re: battery charger question

my battery is an everstart 24m-1000n from walmart.

 

[hedp]

Re: battery charger question

2 or 10 amps is the Maximum Current the charger will deliver in each setting. NOT the amount it WILL deliver.

10 amps will be too much for a 12 volt motorcycle battery, but fine for an auto/boat sized battery.
The charger will attempt to produce ~14.5 volts and the battery will absorb the max current 2/10a until it reaches that voltage.
After that point the voltage will remain constant at ~14.5v but the current will go down.
When set at 10 amps, the last hours of the charge may very well be Less Than 2 amps.
It is how the physics of the Battery Chemistry works.

A 10 amp charger will charge a very depleted auto/boat battery faster than a 2 amp charger, but not anywhere near 5 times faster.
If the battery does not need a significant charge, you may not notice a significant difference between the 2 and 10 amp settings.

The percentage of charge displayed by the charger is a marketing gimmick. Do not put a lot of faith in the indication.

What is the MAKE and MODEL of the Charger you are using?

Is the percentage of charge on all chargers a gimmick?

 

[UncleWillie]

Re: battery charger question

Is the percentage of charge on all chargers a gimmick?

It is not so much a gimmick, as much as, for it to be anywhere near accurate, is need to be calibrated to the particular battery, and the scale is not linear.

Most indicators will measure the batteries voltage or charge current (amps), and apply an conversion factor to estimate the amount of charge.
The results are commonly accurate to only +/- 50%.
Without the history of how the battery came to be at its present state, it is merely an educated guess.

Charging a low battery for a short period and then detaching the charger and reattaching it, usually results in a very optimistically high percent of charge.

Attaching a charger to a fully charged battery result in a pessimistically low reading.

The scale on the OPs charger is just a second scale on the AMP Meter.
High current = Low battery; Low Current = Charged battery. It is only valid on the 10 Amp setting.

The Marketing Department loves to be able to sell the feature.
The Engineering Department just rolls their eyes and smile.

It is about as useful as the Fuel gage on a boat.
Full, Empty, Or something in between; and never very accurate.
But everyone still wants one.