Testing some AA batteries - Non scientific .. Discharge test

old4570 · January 16, 2012, 12:12pm

Anyhow , was a warm [ hot ] day today , and didnt feel like going anywhere , so decided to play indoors and discharge some AA batteries to see how they go ...

Now I had to drop the discharge rate to 200mAh in my Powerex to actually discharge the batteries cos the voltage sag was so brutal for the batteries and they would sag to the cut of voltage on the charger ...

Two batteries failed to discharge a single mAh cos of the Voltage sag ...

Ultracharge Dry Cell - Failed to discharge at even 100mAh rate - ran for 60 minutes in my N-light B2

Eveready blue - Failed to discharge at even 100mAh rate - ran for 75 minutes

Eveready red - 200mAh discharge rate = 126mAh - then ran for 70 minutes

Camelion - 200mAh discharge rate = 138mAh - then ran for 80min

Kodak - 200mAh D/R = 171mAh - 75min

Phillips - 200mAh D/R = 215mAh - 115min

Varta - 200mAh D/R = 1325mAh - 90min

Coles - 200mAh D/R = 1466mAh - 100min

Run time is calculated by putting the battery in my N-light B2 and running the cell down until the light begins to flicker [ very low output and battery is failing ]

Obviously the batteries simply cant be reliably discharged as the voltage drops so badly , so I thought I may as well run them to failure after doing the discharge to get a better picture .

Would be nice to drain every last drop of energy VIA the charger , but it was not going to happen ...

I will be doing more battery experiments as time permits ..

currently playing with the smaller 10440 , and doing some experiments with some really old rechargeable batteries [ resurrecting dead cells ] , interesting !

kreisler · January 16, 2012, 1:01pm

i have a new Powerex too and the Break-In's kill me. 48h for 4 cells, omg. so what kind of cells are yours (Alkaline, Nimh, Nicd)? The manual says "Nimh and Nicd only". i cant perform any further runtime tests until i finished the break-in's will all of my newly purchased 16 Eneloops and 4 old Nimh's. Will take 2 weeks until i am ready to do the runtime tests for my torches (Lumintop Worm, Tank E09, Romisen, Quark, ..).

amraspalantir · January 16, 2012, 1:19pm

pardon for my noob question. what is the proper way to break in a newly bought AA rechargeable battery (eneloop). do i do this periodically for battery maintenance or something? what is the reason for it?thanks

kreisler · January 16, 2012, 2:19pm

i dont know more than this:

www.mahaenergy.com/download/mhc9000.pdf

page2 says this:

old4570 · January 16, 2012, 9:53pm

Those are mainly dry cells , + two Alkaline , always wondered what sort of capacity they had ...

Powerex , you dont have to break in , just cycle them manually 2 or three times if you must ..

You dont need to ..

Reason , if cells degrade [ for what ever reason ] cycling them is a form of exercise to get them back in shape ...

I have a battery pack I havent used in 10 years , it was down to 1 volt , initial charge to termination was some 670mA

This morning the charger alarm went off and nearly 10,000mAh went into charging the cells , this is after cycling the cells several times over several days ..

Out of all my old batteries [ used to start glow motors for CL ] this is the only one I was able to save ...

I will discharge @ 1A today to see if there is any capacity in the battery pack ..

Then I will see about resurrecting Li-ion cells , see if cycling helps restore capacity in any shape or form ...

xxllmm4 · January 17, 2012, 7:54am

Thanks! I have been wanting to do something like this but haven't had the time.

amraspalantir · January 17, 2012, 12:08pm

thanks for the reply's. :)