Testing batteries

[captainvideo462002@yahoo.]

I have a whole pile of AA's AAA's, C's and D's. Many people discard
these at our transfer station and I find that many are perfectly
good. Perhaps their flashlight was not working and so they threw out
all their batteries. I don't know but I would like to come up with a
way to properly load test the various sizes. Does anyone know what
size resistor I might empoy for a given size battery and then what
would be the lowest voltage I would read before I would pronounce that
cell too far gone? Thanks, Lenny.

 

[William Sommerwerck]

I don't have time to go into excruciating detail, but an alkaline cell's
condition is largely indicated by its unloaded voltage. Just sort them by
voltage.

This is not true of carbon-zinc cells, but you rarely see them these days.

 

[Sjouke Burry]

captainvideo462002@yahoo.com wrote:

I have a whole pile of AA's AAA's, C's and D's. Many people discard
these at our transfer station and I find that many are perfectly
good. Perhaps their flashlight was not working and so they threw out
all their batteries. I don't know but I would like to come up with a
way to properly load test the various sizes. Does anyone know what
size resistor I might empoy for a given size battery and then what
would be the lowest voltage I would read before I would pronounce that
cell too far gone? Thanks, Lenny.
The short circuit current is a nice indication of charge left.

I test them with a multimeter at 20 amp range, and sometimes
compare with a full(new) battery.

 

[Charles]

"Sjouke Burry" <burrynulnulfour@ppllaanneett.nnll> wrote in message
news:4a29a7c1$0$1637$703f8584@textnews.kpn.nl...

captainvideo462002@yahoo.com wrote:
I have a whole pile of AA's AAA's, C's and D's. Many people discard
these at our transfer station and I find that many are perfectly
good. Perhaps their flashlight was not working and so they threw out
all their batteries. I don't know but I would like to come up with a
way to properly load test the various sizes. Does anyone know what
size resistor I might empoy for a given size battery and then what
would be the lowest voltage I would read before I would pronounce that
cell too far gone? Thanks, Lenny.
The short circuit current is a nice indication of charge left.
I test them with a multimeter at 20 amp range, and sometimes
compare with a full(new) battery.

I do that too ... but if you blow the fuse in a Fluke, it can be hard to
replace. Use a series load.

 

[hr(bob) hofmann@att.net]

On Jun 5, 7:07 pm, "Charles" <charlesschu...@comcast.net> wrote:

"Sjouke Burry" <burrynulnulf...@ppllaanneett.nnll> wrote in message

news:4a29a7c1$0$1637$703f8584@textnews.kpn.nl...

captainvideo462...@yahoo.com wrote:
I have a whole pile of AA's AAA's, C's and D's. Many people discard
these at our transfer station and I  find that many are perfectly
good. Perhaps their flashlight was not working and so they threw out
all their batteries. I don't know but I would like to come up with a
way to properly load test the various sizes. Does anyone know what
size resistor I might empoy for a given size battery and then what
would be the lowest voltage I would read before I would pronounce that
cell too far gone?  Thanks, Lenny.
The short circuit current is a nice indication of charge left.
I test them with a multimeter at 20 amp range, and sometimes
compare with a full(new) battery.

I do that too ... but if you blow the fuse in a Fluke, it can be hard to
replace.  Use a series load.

It depends a little on what use you will make of the used batteries. I
would suggest a 10 to 20 ohm resistor, that will load the battery to
between 50 and 100 Milliamperes (ma), which is a reasonable load. I
would look for an output of at least 1.25 volts at that range. Try a
pair of lw-edge batteries After you have tested a few, and try them in
your proposed application and see how they work. If ok, then you can
use all batteries that meet that voltage level. If they are too weak,
select a pair from a higher range and try those, until yuo find the
minimum test voltage that cells meet the then work ok in your
application. Or, just try them in a flashlight and see if they are
bright enuf. That's what I do when I am too lazy to break out my
voltmeter.