🍺 ◾️ 👩🏼‍✈️ Crohn Battery Test 👈🏽 👩‍👦‍👦 👩🏼‍🚒

I always wondered how expensive batteries differ from cheap ones and how big the difference between salt and alkaline batteries is. I tested 12 batteries of the type "Krona" and share the results.

In 2014, I staged a “Grand Battery Test” ( habr.com/ru/company/madrobots/blog/364773 ), testing 255 “finger” and “little” batteries AA and AAA. In 2018, I did a test of cheap AAA batteries, in 2019, another test of AAA batteries ( habr.com/ru/company/lamptest/blog/458856 ).

I have long wanted to test many types of batteries, and now I have started this big business.

First of all, it was decided to test the Krona, because before the test I didn’t even know approximately how much energy they gave.

The Krona battery has a rated voltage of 9 volts and contains six one-and-a-half-volt cells inside.

Salt "Crones" are called 6F22, they have a metal case and six "tablets" inside. The initial voltage of such a battery is about 10 volts.

Alkaline (alkaline) “Crones” are called 6LR61, they have a plastic case and six AAAA cylindrical elements inside. The initial voltage of such a battery is about 9.6 volts.

For testing, we used a modified EBD-USB + device in voltage logger mode. It connects to a computer and writes to the file the exact voltage values on the battery every two seconds.

The device has a built-in electronic load and a current measurement function, but I did not use them: the current is measured with an accuracy of 1 mA, which is not enough in this case, and it is better to use a constant resistor as a load for the Kron so that the discharge current decreases by as the voltage from the battery drops.

A resistor with a resistance of 234.0 Ohms (resistance was measured with an accurate multimeter) was used as the load, while the current during the discharge dropped from 40 to 23 mA.

It took 6 to 22 hours to discharge one battery.

Manufacturers indicate a storage period of 3 years for Krona salt batteries, for alkaline batteries from 3 to 10 years. Five fresh batteries (3 alkaline, 2 saline), two alkaline batteries with an expiring shelf life, a salt battery with a recently expired battery and an alkaline battery released in 2013, which expired in 2016, took part in the test.

This is how the discharge curves of the tested batteries look.

It’s immediately obvious that something is wrong with the batteries of Era and Videx.

The "Era" is alkaline, it had a shelf life of up to 09.2020 (there is no release date), but the initial voltage is only 8.76 V. It seems that it just got defective.

"Videx" saline, released in October 2016, expiration date to 10.2019, that is, overdue for six months. The initial voltage is 9.73 V.

The yellow nameless battery from Auchan expired three and a half years ago, in 2016. It gave less energy than other alkaline batteries, but not as little as might be expected. Its initial voltage is also slightly below normal - 9.19 V.

Interestingly, different batteries behave very differently. Some gradually discharge to the end, while others gradually discharge to a certain point, and then the voltage on them drops sharply.

Discharge results up to 5.4 V (each element discharged up to 0.9 V).

The best alkaline battery (it turned out to be a cheap Ergolux for 90 rubles) gave 4.38 Wh.

Trophy has a minimum power consumption of “fresh” alkaline batteries - 3.74 Wh (15% less than the leader).

The cheap battery from Auchan, which is already seven years old, and whose shelf life expired three and a half years ago, gave 3.14 Wh of energy, which is only 16% less than the new Trophy.

New salt batteries provide 0.86-1.03 Wh energy, that is, 3-5 times less alkaline.

The load of 40 mA for the salt “Krona” is too high (however, the existing radio microphone powered by the “Krona” consumes just 40 mA), so I bought another Kodak and Camelion battery and conducted the second test, using a resistor as the load 397.4 Ohms (discharge current from 23 to 14 mA).

The graph shows that salt batteries with such a load are much easier to operate.

In this mode, salt batteries produce significantly more energy. The Kodak battery gave 1.26 Wh (in the first test it was 0.86 Wh), Camelion - 1.3 Wh (in the first test 1.03 Wh), and Camelion is obviously better able to withstand heavy loads.

All test data can be found in the excel file krona.xls . There are discharge results up to 4.2 V (0.7 V on each element), initial voltages and the weight of all batteries, production dates, barcodes.

Of course, in order to draw general conclusions, the data of one, not very voluminous test is not enough, but now we can highlight the following points:

Like other batteries, the difference between different models of batteries of the same chemistry is not very large and is unlikely to exceed 30%.
Crohn's salt batteries provide 3-5 times less energy than alkaline batteries. They can be used in devices with low power consumption (less than 25 mA), but in devices with a higher consumption, the difference with alkaline will be even greater.
Cron batteries with high self-discharge come across. To test the battery, it is advisable to measure its voltage. For a new alkaline (Alkaline) battery, it should be above 9.3 volts, for a salt one - above 9.9 volts.
Expired alkaline batteries can be used, although they will give less energy than new ones. The condition of such a battery can be determined by measuring the voltage.

Crohn Battery Test

More articles: