Test Batboostor on different brands of batteries

[Petrus]

Hello
According to the manufacturer, the batboostor ( https://www.econologie.com/shop/chargeur ... lines.html ) charges some brands of batteries better than others, I thought it would be interesting to do some tests on several brands of batteries.
So I made myself a test bench that will determine the capacity of the batteries once recharged.

The test bench consists of a constant current load:

The charger case only serves as a battery holder.

and a digital recorder:


The recorder is programmed to cut off the load as soon as the battery voltage is less than 1V.
Then it only remains to transfer the data to PC for analysis.
I think to set the load to 100mA and note the time during which the voltage is greater than 1,2V to determine the capacity.
Is there a standard for measuring battery capacity?

[I Citro]

I don't know if there is a standard, but we can create one ...
Just take a few current devices running on batteries and see (manual or real test) the operating time before they stop. Then measure the battery voltage ...
then you just have to reproduce these real parameters on your test circuit. Here

[Petrus]

So here are the results for duracell ultra M3 and varta max tech on two charge - discharge.
The winner is ... duracell, by far!

They get 715 mah for the first charge and 626 mah for the second, on the other hand, their internal resistance is 0,5 Ohms after the first charge and 1 ohm after the second, so we cannot use them on devices consuming a lot current.

Varta max tech, they simply do not recharge: 18mAh and 26mAh respectively after the first and second charge.

The excel files with data and graphics are there:
http://petrus44.free.fr/Divers/Duracell_m3_AA.xls
http://petrus44.free.fr/Divers/Varta_max_tech_AA.xls


PS: remember that varta is the author of a very questionable ad on an ecological level:
http://www.fr.varta-consumer.com/conten ... nsumer.com

[Christophe]

Thank you for these results!

Apparently the Energizer would also be a problem if you could test 2?

For the varta we bought 1 package for testing precisely ... and it was not very convincing either on our side (but not measured).

By cons of "unbranded" and panasonic have worked well (ten regeneration)

[Capt_Maloche]

I agree for the Varta, I have 2 who "blew" me in the face

[Christophe]

Ours have not "farted" but after 2 regeneration they were out of order ... Weird this story of variation depending on the brands anyway ... I thought that an alkaline battery was an alkaline battery ...

[Capt_Maloche]

You're going to do a dissection and photos, right?

[elephant]

superb measurement campaign, there are certainly different recipes for making batteries, but in your test, was the discharge also standardized?
With lead-acid batteries in alarm, we know the following phenomenon well:

when a battery (12 V) has been discharged up to 10,5 V, it recharges without problems with an acceptable loss of capacity (variable depending on the age of the battery, of course)

Between 8,5 and 10,5: sometimes we are lucky with the right brands

below 8,5 V: no need to get tired

the voltages are measured on the installation, before restoring the sector

[Petrus]

Very good elephant question

In the file available here: http://www.ni-cd.net/accusphp/theorie/a ... /index.php
It is recommended not to go below 1,25V per battery.

But a device can work very well with a voltage lower than 1,25V / batteries.
So I put a threshold voltage of 1V to be closer to reality and it allows me to compare with 1,2V batteries.

[Petrus]

I tested energizers
It gives about the same as varta, I get 19mA
http://petrus44.free.fr/Divers/Energizer_AA.xls
The residual voltage before charging was not great (0,8V and 0,98V), but I think the results are more related to their chemistry, like on the varta.

The duracells have undergone a new charge / discharge cycle. The internal resistance has further increased to 1,4 ohms but I still get 559mAh
http://petrus44.free.fr/Divers/Duracell_m3_AA.xls

I'm going to try to deeply discharge the duracell to see how they behave.