Battery (not for quad)

[ohsobad_chevy]

I have a 6 volt, 4.5 AH battery......how can I tell how many amps and ohms the battery is........If you cant tell, I am clueless on this stuff. :confused:

[Pappy]

it's a 4.5 amp hour battery 6 volt.

[pro-rider46]

you can always get a ohm meter, they are very nice to have around for any projects

[ohsobad_chevy]

Originally posted by Pappy
it's a 4.5 amp hour battery 6 volt.

Right.....but does that mean that it is a 4.5 amp battery......what does amp hour mean? :confused:

[wilkin250r]

4.5 AH is capacity. In theory, the battery can supply 4.5 amps for one hour before it's dead. It's cumulative, so you can get any configuration, like 2.25 amps for 2 hours, or 1 amp for 4.5 hours.

The definition of "dead" is below 10.5 volts.


Like I said, this is theoretical. You might not get a full hour at 4.5 amps, because the rating is measured on a 20hr discharge. If you actually try to cut that down to one hour, you probably won't get anywhere near theoretical.


I can tell you a method for measuring the internal resistance of the battery, but first YOU need to satisfy my curiosity. Why do you want to know the internal resistance?

[<DRS>GPF]

Originally posted by wilkin250r
4.5 AH is capacity. In theory, the battery can supply 4.5 amps for one hour before it's dead. It's cumulative, so you can get any configuration, like 2.25 amps for 2 hours, or 1 amp for 4.5 hours.

The definition of "dead" is below 10.5 volts.


Like I said, this is theoretical. You might not get a full hour at 4.5 amps, because the rating is measured on a 20hr discharge. If you actually try to cut that down to one hour, you probably won't get anywhere near theoretical.


I can tell you a method for measuring the internal resistance of the battery, but first YOU need to satisfy my curiosity. Why do you want to know the internal resistance?

good explanation, id be interested in hearing how you measure the internal battery resistance as well.

ive theorized for groups on the apparent resistance, but its only relevant to the supply voltage feeding the battery, or on the other end, the batteries CCA value(maximum amperes at 10.5 out).. neither are accurate, but it helps to describe the action/reaction of a battery charger.

[Pappy]

resistance is mute these days, conductance is what we use today to define a batteries ability to perform its intended task. the last 4 years has seen an explosion in conductance technology that has led to several new means of testing the batteries ability to flow current. an impedence in that flow will cause a ripple in the conductance wave and can now be detected by use of the new testers. i can have someone that has no knowledge of batteries testing units in 3 minutes with 97% of the accuracy of someone with a multimeter, a book of charts and years of expierence! funny how its changed over the last 20 years:p

resistance in a battery can be explained best by a kinked hose. same as the water flow from a hose would be restricted or cut off, the energy (either charging or discharging) can be affected by a weakening or damaged cell. with matrix grid design, and the explosion of AGM technology, conductance testing is the fastest and most effective means to test with. conductance testing employs a small ac signal to the battery and one can test the battery with out load testing or aging the battery. also much safer...lol

with regards to cell phone batteries and the like, milliohms is where you want to be reading when using a multimeter. i dont work with those batteries often. searching for low resistance in these units isnt all that hard, just get the ratings and figure your draw and chart the readings(you will need to know the pulse currents of the device i.e. cell phone or battery powered device) im sure wilkin is way more in tune with this end of the deal, but its not super hard to get most any info you would need.

[<DRS>GPF]

Originally posted by Pappy
resistance is mute these days, conductance is what we use today to define a batteries ability to perform its intended task. the last 4 years has seen an explosion in conductance technology that has led to several new means of testing the batteries ability to flow current. an impedence in that flow will cause a ripple in the conductance wave and can now be detected by use of the new testers. i can have someone that has no knowledge of batteries testing units in 3 minutes with 97% of the accuracy of someone with a multimeter, a book of charts and years of expierence! funny how its changed over the last 20 years:p

resistance in a battery can be explained best by a kinked hose. same as the water flow from a hose would be restricted or cut off, the energy (either charging or discharging) can be affected by a weakening or damaged cell. with matrix grid design, and the explosion of AGM technology, conductance testing is the fastest and most effective means to test with. conductance testing employs a small ac signal to the battery and one can test the battery with out load testing or aging the battery. also much safer...lol

with regards to cell phone batteries and the like, milliohms is where you want to be reading when using a multimeter. i dont work with those batteries often. searching for low resistance in these units isnt all that hard, just get the ratings and figure your draw and chart the readings(you will need to know the pulse currents of the device i.e. cell phone or battery powered device) im sure wilkin is way more in tune with this end of the deal, but its not super hard to get most any info you would need.


http://www.battcon.com/PapersFinal2003/StukenbergPaperFINAL2003.pdf

thats very interesting.. now if i can just get every boat owner in north america to buy one. :D

[Pappy]

lol..i sell midtronics testers on a daily basis:p

[ohsobad_chevy]

Originally posted by wilkin250r
.........
I can tell you a method for measuring the internal resistance of the battery, but first YOU need to satisfy my curiosity. Why do you want to know the internal resistance?

I was just curious......I have a 6 volt charger and there are 2 settings......one for 2 amps and one for 6 amps. I was just curious if it needed to be charged on 2 amps or if I can charge it on 6 amps.

[Pappy]

start with 2 amps. fully discharged it should require 2.5 hours to bring the battery to full charge (4.5 ah battery)6 amps will overcharge the unit and you run the risk of overheating the sealed unit and that aint good

[ohsobad_chevy]

OK, appreciate it