AA Alkaline continuous Discharge Test

This thread is about the finding of which alkaline cells perform best and how each perform under a continuous discharge load.

Update 2010-01-18: Table updated with TESCO branded batteries

All cells are purchased off the retail malls/shops. Using Sanyo Eneloop as the base reference. Discharge equipment used is MAHA MH-C9000 WizardOne Charger-Analyzer, manufacturing date code 0I0BA, room temperature 25-28 degree celcius.

First, some legend:
M - Manufacturing Date
E - Expiry Date
CHN - China
IND - Indonesia
JPN - Japan
SGP - Singapore
USA - USA
THL - Thailand
!! - MAHA MH-C9000 display DONE immediately upon inserting battery or last discharge current is less than 20mAh

List of batteries tested:

Duracell Alkaline


Sanyo Alkaline


Panasonic Alkaline


Panasonic Evolta


Energizer e2 Advanced


Energizer MAX


Ikea AA- thanks polkiuj

TESCO Batteries - thanks pseudoblue
TESCO Value Zinc chloride (ok, this is not alkaline...)
TESCO Everyday
TESCO Power Hi Tech

The discharge function in MAHA MH-C9000 allows to select the discharge rate desired, in this test, we will focus on a discharge current of 500mA and 1000mA on the 1st discharge, while subsequent discharge current at 200mA. MH-C9000 will discharge each cell down to 0.90V and terminate, the word DONE will be display at the LCD.
A rest of at least 1 to 2 hours between discharge cycle to allow the cell Voltage to rebound and stabilize.

Here is the results:


The numbers are what displayed at MH-C9000 LCD after it's done discharging for the cycle.
The above result serves only as an alternative to what you may find on the Internet and cpf, it is not to be taken as authoritative reference, I'm NOT in any way a battery expert, but a curious consumer that happens to have an interesting equipment that allows me to do some testing and experimenting. I'm surprised to have found how some cells performs in the least expected manner.

As some cells performance are quite unexpected, I'll be doing more testing and update this thread as soon as the testing and data gathering is done.

This is the first time I'm doing this, so I greatly appreciate your pointing out any short-comings and mistakes I've made and I will try my best to correct it in future version and testing. TIA.

Observations (WIP):
- I've recorded the voltage after 30 minutes of discharge, at 0.5A, Eneloop is reading ~1.21V while all alkaline cells tested reads between 1.03-1.18V; at 1.0A discharge, Eneloop is reading ~1.14V while all alkaline cells drop below 1.05V.

Note:
- As pointed out by Tom (SilverFox): "there are often variations in cell performance with different batches of cells and from cells purchased at different locations", so YMMV.

for those who lives in SEA, I have another version with pricing information link here, the default currency is in Ringgit Malaysia

Good information. Thanks for testing and sharing your results.

One small quibble: mAh is a measure of current over time. When you are measuring the discharge current it is just mA. If the battery discharges at 500 mA for one hour, you'd say that's 500 mAh.

beamis said:

Good information. Thanks for testing and sharing your results.

One small quibble: mAh is a measure of current over time. When you are measuring the discharge current it is just mA. If the battery discharges at 500 mA for one hour, you'd say that's 500 mAh.

Click to expand...

That's true. Hehe.

Thanks Rookiedaddy! So happy to see the Ikea performances! Wow! For the price it's the best battery out there! (value)

Duracells puzzle me. How come it has more capacity discharged @ 1A than 0.5A?

beamis said:

One small quibble: mAh is a measure of current over time. When you are measuring the discharge current it is just mA. If the battery discharges at 500 mA for one hour, you'd say that's 500 mAh.

Click to expand...

Thanks beamis. Corrected some of the wording, table's column title remains as it's the discharge rate selected in MH-C9000. Thanks for the pointers. Appreciate it. :thumbsup:
EDIT: oops, I've rechecked, it's mA, now column title corrected.

polkiuj said:

Duracells puzzle me. How come it has more capacity discharged @ 1A than 0.5A?

Click to expand...

I believe each cell has different capacity. But in this case, the total capacity of Duracell:
Discharge at
~0.5A => 793 + 303 = 1096mAh
~1.0A => 1048mAh (no further discharge is possible on this cell after the first discharge)

yes, some of the data collected is really interesting, perhaps some are purpose for high current drain while others are for low current drain, and yet some are not meant to be drain continuously.

These Duracell are OEM packed and made in China. I can't locate any made in USA Duracell locally so unable to test the difference. I'll do another round of testing for some the cells and will add new cells once I get my hands on them.

Battery image uploaded and some mistakes corrected.

I'm confused, you discharged a battery at 500 mAh (for an hour), then discharged that same battery at 200mAh for another hour, then discharged that same battery at 200mAh for another hour ???

Hello Rookiedaddy,

Excellent work.

Keep in mind that the C-9000 uses pulse discharging, which comes very close to constant current discharging, but there is still some differences. As a relative check, it doesn't amount to much, but it does factor in when you are comparing your results with manufacturer data sheets.

With that said, relative differences between brands will show up fine with either method of discharge testing.

In casual and formal testing I have found that there are often variations in cell performance with different batches of cells and from cells purchased at different locations. Unless you test a large sample of cells, it is difficult to trend the various brands. However, I find the "snap shoot" information informative and useful.

You may also find this thread informative...

Tom

Hello ltiu, the discharge is done using MAHA MH-C9000 discharge function. This will discharge the cell at user selected discharge rate (500mA/1000mA) until the cell Voltage reaches 0.90V, not *for an hour*. Take the "Ikea AM3 E:2014-08 (CHN)" cell for example, at discharge rate of 500mA, it took 174 minutes until it reaches 0.90V and C9000 terminates the discharge which gives the reading of 1327mAh. Subsequent discharge after the cell Voltage rebound is set at 200ma to continue to drain the rest of available energy.

This test is the result of my curiosity to find out how different cells perform under continuous medium and high load, and what to plan for and expected of different cells in different devices. Hope this clarify the confusion.
=============================================

Hello Tom, thanks for the advise and pointers. your excellent thread is one that I refer to before and during my testing. Been re-reading it a half dozen times.

I'm curious to what manufacturer claims sometimes, as their marketing will always come-up with creative way to interpret the datasheet. Hence the test to find out how different cells perform.

I've added a note to variation of cells from different batches. Thanks for the heads-up. :thumbsup:

rookiedaddy said:

Hello ltiu, the discharge is done using MAHA MH-C9000 discharge function. This will discharge the cell at user selected discharge rate (500mA/1000mA) until the cell Voltage reaches 0.90V, not *for an hour*.

Click to expand...

Got it, thanks.

love it, the second wind test just what an alkaline needs.

Hey bro, interesting test methods and the results are surprising! Very informative indeed :thumbsup:

1st post updated with TESCO branded batteries.

Would you consider doing some tests on the Asda Long life cells please?

Hello Magic Matt, yes, I would. However, after a brief search, I couldn't get hold of Asda branded batteries locally. Do you know from whom they OEM from? Are these Asda batteries made in China?

No idea who makes them I'm afraid, it's just they always seemed to outlast Duracells in my digital camera. I was almost hoping maybe that testing them may reveal who manufacturs them.

I will try and duplicate your tests on some when I get my C-9000 (oh the agony of waiting!).

great! let us know your test results when you have them.

I'm hoping to get hold of some US-made cells later, pretty hard to come by locally except the Energizer Lithium.

I've got a fresh package of duracell alkaline AA, marked as "made in usa", and a c9000 on order. With a little time to learn how to use the charger, I can get you numbers from those cells when it gets here.

Hello UserName, that's great! lovecpf

On some of my recent testing, I've also recorded the Voltage and mAh reading upon the 1st 30 minutes of every cycle. Will put the data up after completed some re-testing. I also hope to make the worksheet available for download later.

Nice work, and some interesting results you have there.

Those Duracell readings do look pretty strange, both with the very poor overall capacity with an initial 0.5A discharge, and with the 1A reading being seriously better than the 0.5A, which isn't at all what would be expected in general, or even from the Duracell datasheets.

yup, the Duracell readings do seems strange. I'm doing another round of testing for these Duracell now, will update the results soon. These are in OEM packing -- 2 cells pack in shrink-wrap. I'm not sure if there are any difference between OEM and retail packing for these Duracell as both are made in China, I will get some retail blister pack Duracell to test later.