How to test a battery for amperage?

[huntinfool]

I have 20+ batteries around our shop that I want to test and see if they have any amperage. I can test for voltage no problem, but is ther a way to test amperage? I don't want to have to load them all up and take them to Wal-mart or the auto parts store to test them on their tester. I don't want to buy a tester either so is there a way? Maybe something on my mulitmeter?

 

[russ010]

I may be wrong, but I think you have to buy a load tester to actually get the readings you are looking for

https://www.amazon.com/Actron-CP7612-Battery-Load-Tester/dp/B0009XQUJI

 

[huntinfool]

Thats what I was afraid of. I hate to buy a load tester to determine which batteries are good or not and then never using it again.

 

[redbug]

go to the local auto shop if the have a portable load tester they may lend it to you if you leave a deposit.
some auto parts places will do the same thing.
just don't look like a thief when you show up

 

[KMixson]

You can try this charger. I use mine all the time on my RC aircraft and other items with rechargeable batteries. I can charge a battery and see just how many milliamp or amp hours I have used in the battery. 1000 milliamps = 1 Amp. It charges Nickel Cadmium(NiCd), Nickel Metal Hydride(NiMH), Lithium Polymer(LiPo), Lithium Ion(Li-Ion), and lead acid(Pb) batteries. It has a lot of settings you can chose from. I can cycle(discharge and charge) my NiCd's up to 10 times to remove the "memory" that can hurt your battery capacity.
I can charge my boat battery with it also and tell just how many amps I have used for a day of fishing. It will even charge 24 volt Pb systems. The one other thing is that you need is a 12 volt power supply to run it. It has alligator clips to power it in the field from a 12 volt battery. I have a 25 amp regulated power supply to run this charger at home.


https://www.electrifly.com/chargers/gpmm3153.html

 

[Truckmechanic]

go to the local auto shop if the have a portable load tester they may lend it to you if you leave a deposit.
some auto parts places will do the same thing.
just don't look like a thief when you show up

Good idea RedBug!!...I hadn't thought of that.

The auto parts stores here will lend it to you for a deposit of the purchase price. When you take it back, you get your money back. That would save you from having to buy one and will probably give you the best test on your battery.

 

[huntinfool]

Yeah I had already thought of that. I was more wondering if there was another way to do it without the load tester. Maybe some mathmatical formula. I will go to the auto parts store and ask to use theirs and figure out which ones are good and which ones are not.

Thanks for the input!

Hey Kmixon how much do those things run? That looks very interesting.

 

[KMixson]

Hey Kmixon how much do those things run? That looks very interesting.

Here is the link to Tower Hobbies website. It cost $84.98

https://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXMAJ0&P=ML