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Battery charger confusion

#1

B

bt-77

Hi, I had just bought a used battery charger and I have no clue what amp setting to put it on to charge my 12 volt lawnmower battery. The charger has 50,10, and 2 amp settings on it. What amp is best for lawn mower battery? Thanks


#2

StarTech

StarTech

10 amp for lead acid battery; although, 2 amp is slow charge way. 50 amp is considered jump start method for automobiles.


#3

A

Auto Doc's

No higher than 10A for 1hour. Place it on 2A if you have time to let it set and slow charge. 50A is for a quick start, but you risk blowing the main fuse.

If you need a battery, don't put it off because the mower will damage the charging circuit. For battery longevity, get a solar panel battery maintenance charger and leave it on the battery (while outside in the sun) at all times when not using the mower. It will triple your battery life. I have been using them for years and it works.


#4

Tiger Small Engine

Tiger Small Engine

bt-77 said:
Hi, I had just bought a used battery charger and I have no clue what amp setting to put it on to charge my 12 volt lawnmower battery. The charger has 50,10, and 2 amp settings on it. What amp is best for lawn mower battery? Thanks
Click to expand...
2 amp trickle charge is the best. Hook it up and come back next day. It will float once fully charged and not overcharge the battery. Remember most of the newer chargers less than 25 years old will not recognize a battery and start charging unless battery is at 12.0 volts or higher.


#5

S

slomo

Lower amp rate the better for battery longevity.

Quick chargers with a ton of amps are battery killers.


#6

B

bt-77

So
Tiger Small Engine said:
2 amp trickle charge is the best. Hook it up and come back next day. It will float once fully charged and not overcharge the battery. Remember most of the newer chargers less than 25 years old will not recognize a battery and start charging unless battery is at 12.0 volts or higher.
Click to expand...
So will a discharged battery still read 12.0 volts on the new chargers?


#7

B

bt-77

So basically all
Auto Doc's said:
No higher than 10A for 1hour. Place it on 2A if you have time to let it set and slow charge. 50A is for a quick start, but you risk blowing the main fuse.

If you need a battery, don't put it off because the mower will damage the charging circuit. For battery longevity, get a solar panel battery maintenance charger and leave it on the battery (while outside in the sun) at all times when not using the mower. It will triple your battery life. I have been using them for years and it works
Click to expand...


#8

B

bt-77

So
Auto Doc's said:
No higher than 10A for 1hour. Place it on 2A if you have time to let it set and slow charge. 50A is for a quick start, but you risk blowing the main fuse.

If you need a battery, don't put it off because the mower will damage the charging circuit. For battery longevity, get a solar panel battery maintenance charger and leave it on the battery (while outside in the sun) at all times when not using the mower. It will triple your battery life. I have been using them for years and it works.
Click to expand...

Auto Doc's said:
No higher than 10A for 1hour. Place it on 2A if you have time to let it set and slow charge. 50A is for a quick start, but you risk blowing the main fuse.

If you need a battery, don't put it off because the mower will damage the charging circuit. For battery longevity, get a solar panel battery maintenance charger and leave it on the battery (while outside in the sun) at all times when not using the mower. It will triple your battery life. I have been using them for years and it works.
Click to expand...
So basically there are 2 ways to charge a lawn mower battery. I can either fast charge battery at 10 amps or slow charge battery at 2 amps? Which do you prefer?


#9

B

bt-77

When you
slomo said:
Lower amp rate the better for battery longevity.

Quick chargers with a ton of amps are battery killers
Click to expand...


#10

B

bt-77

bt-77 said:
When you
Click to expand...
When you say low amp, what amp are you saying you use for a lawn mower battery?


#11

M

MParr

www.batterytender.com

Junior 12V, 800mA Battery Charger - Available at Walmart

Available at Walmart The Battery Tender® Junior 12V, 800mA Battery Charger and Maintainer is all you need to stay charged, extend your vehicle's battery life. It's easy to use, safe and secure. STAY CHARGED Boost your ride’s battery life with the Battery Tender® Junior Automatic Battery Charger...
www.batterytender.com www.batterytender.com


#12

S

slomo

bt-77 said:
So

So will a discharged battery still read 12.0 volts on the new chargers?
Click to expand...
12.0 needs charged. 12.6 is fully charged with no surface charge on it.


#13

F

Firespooks

bt-77 said:
Hi, I had just bought a used battery charger and I have no clue what amp setting to put it on to charge my 12 volt lawnmower battery. The charger has 50,10, and 2 amp settings on it. What amp is best for lawn mower battery? Thanks
Click to expand...
With any battery, it is best to use slow charge at a low amp setting. This reduces overheating the battery. I learned this from an Interstate Battery class.


#14

G

Gord Baker

bt-77 said:
Hi, I had just bought a used battery charger and I have no clue what amp setting to put it on to charge my 12 volt lawnmower battery. The charger has 50,10, and 2 amp settings on it. What amp is best for lawn mower battery? Thanks
Click to expand...


#15

grumpyunk

grumpyunk

The 2A setting is for motorcycle batteries and those of similar capacity. If you charge a small battery at a higher rate it will make the battery temperature rise.
Many new batteries that are shipped w/o electrolyte will have instructions to charge around 2A.
My OLD Sears charger has 8A/2A setting, with the lower rating variable using a knob to dial in the rate you want. It was sold by Sears as an Auto/Motorcycle battery charger.
Charging any size battery at the fastest rate possible is not good for the longevity of the battery. Those who say different should read up a bit IMO.
tom


#16

M

Matergrower

bt-77 said:
Hi, I had just bought a used battery charger and I have no clue what amp setting to put it on to charge my 12 volt lawnmower battery. The charger has 50,10, and 2 amp settings on it. What amp is best for lawn mower battery? Thanks
Click to expand...
I have one, Use 50a for starting and 10 for charging. 2 amp is for trickle charging.


#17

ILENGINE

ILENGINE

grumpyunk said:
The 2A setting is for motorcycle batteries and those of similar capacity. If you charge a small battery at a higher rate it will make the battery temperature rise.
Many new batteries that are shipped w/o electrolyte will have instructions to charge around 2A.
My OLD Sears charger has 8A/2A setting, with the lower rating variable using a knob to dial in the rate you want. It was sold by Sears as an Auto/Motorcycle battery charger.
Charging any size battery at the fastest rate possible is not good for the longevity of the battery. Those who say different should read up a bit IMO.
tom
Click to expand...
What always get me is they say to connect motorcycle and atv batteries to a 1.5-2 amp charger for charging and then you drop that same battery into your atv and connect it to the 20 amp charging system. The same with lawnmower batteries. And just because you connect that battery to a 20 amp charger doesn't mean the battery will except or the charger will put that full amperage into the battery. The old manual chargers would deliver the full amperage, but the automatic chargers used today will vary the output depending on level of charge.


#18

C

cliffeby

bt-77 said:
Hi, I had just bought a used battery charger and I have no clue what amp setting to put it on to charge my 12 volt lawnmower battery. The charger has 50,10, and 2 amp settings on it. What amp is best for lawn mower battery? Thanks
Click to expand...
To bring it up to charge, use the 10A setting. To maintain for a month or more of non-use, use the 2A setting.


#19

F

Freddie21

As they indicated, 2amp is best for the battery. 10amp if you need it quick.


#20

ILENGINE

ILENGINE

grumpyunk said:
The 2A setting is for motorcycle batteries and those of similar capacity. If you charge a small battery at a higher rate it will make the battery temperature rise.
Many new batteries that are shipped w/o electrolyte will have instructions to charge around 2A.
My OLD Sears charger has 8A/2A setting, with the lower rating variable using a knob to dial in the rate you want. It was sold by Sears as an Auto/Motorcycle battery charger.
Charging any size battery at the fastest rate possible is not good for the longevity of the battery. Those who say different should read up a bit IMO.
tom
Click to expand...
What always get me is they say to connect motorcycle and atv batteries to a 1.5-2 amp charger for charging and then you drop that same battery into your atv and connect it to the 20 amp charging system. The same with lawnmower batteries. And just because you connect that battery to a 20 amp charger doesn't mean the battery will except or the charger will put that full amperage into the battery. The old manual chargers would deliver the full amperage, but the automatic chargers used today will vary the output depending on level of charge.


#21

jes_in_sac

jes_in_sac

Definitely not the 50A setting which is supposedly for starting, although I've never seen one be able to start anything but a lawnmower or motorcycle sized engine. Most chargers will have an automatic charging circuit, unless it's very old and very basic. So whether you do a 10A fast charge, or a 2A slow charge, when the battery is fully charged, the charger should shut the primary charging current off charging mode and go to a maintenance mode. Under normal circumstances, the 2A low amp slow charge is best for the battery, and use the 10A fast charge if you found your battery dead or ran it down trying to get the engine running and it wouldn't start for whatever reason, and need to use the mower and give it a few minutes at fast charge to put just enough juice in it to start it up, or work on the engine again to try to get it running.


#22

R

RevB

bt-77 said:
Hi, I had just bought a used battery charger and I have no clue what amp setting to put it on to charge my 12 volt lawnmower battery. The charger has 50,10, and 2 amp settings on it. What amp is best for lawn mower battery? Thanks
Click to expand...
A typical charging rate for a lead-acid battery used in a lawnmower is 1 to 3 amps. Manufacturers recommend a charge C-rate of 0.3C, but some research suggests lead-acid batteries can be charged faster, up to 1.5C, as long as the current is managed towards full charge. A 12-volt lawnmower battery should be fully charged between 12.6 and 12.8 volts.

You should really do some research about charge rates vs capacity. Anyone who suggests 10 amps is putting you and the battery in danger from overheating and explosion.


#23

B

bt-77

RevB said:
A typical charging rate for a lead-acid battery used in a lawnmower is 1 to 3 amps. Manufacturers recommend a charge C-rate of 0.3C, but some research suggests lead-acid batteries can be charged faster, up to 1.5C, as long as the current is managed towards full charge. A 12-volt lawnmower battery should be fully charged between 12.6 and 12.8 volts.

You should really do some research about charge rates vs capacity. Anyone who suggests 10 amps is putting you and the battery in danger from overheating and explosion.
Click to expand...
I am doing research. That is why I asked this question so I know what is a safe amp to charge lawn mower battery on.


#24

R

RevB

bt-77 said:
I am doing research. That is why I asked this question so I know what is a safe amp to charge lawn mower battery on.
Click to expand...
Problem is.....the answers you'll get here may be way wrong. Try something like this :

batteryuniversity.com

BU-403: Charging Lead Acid

BU meta description needed...
batteryuniversity.com batteryuniversity.com

There are other pages for different chemistries.


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