We charge ordinary batteries

Many of you will be surprised to find out that ordinary alkaline batteries can be charged using a special charger. I conducted an experiment to find out how much energy the batteries can give after recharging.

I only know two models of battery chargers. The first device is sold on Aliexpress, costs about 600 rudders, charges only batteries and is powered by USB.

The second device – ROBITON Ecocharger AK02 costs about 900 rubles, charges both batteries and rechargeable batteries, and is powered from the network.

Charge mode is switched on the side of the device.

The device charges the batteries with a current of 350 mA, the batteries are charged with a current of 100-150 mA.

You can charge batteries and rechargeable batteries of the formats AA and AAA, the device has four independent channels. Two-color LEDs show the status of each channel, so at the same time it is also a good charge for batteries.

For the experiment, I took the new AA and AAA batteries of two brands – the notoriously good GP Super and one of the cheapest FLARX from FixPrice stores. Each type has three pieces, a total of 12 pieces.

At first, all the batteries were discharged in three modes with a capacity measurement:

1. Discharge in the “constant resistance” mode with an initial current of 200 mA;
2. Discharge in the “constant resistance” mode with an initial current of 1000 mA;
2. Discharge by pulses (10 sec load, 20 sec pause) in the “constant resistance” mode with an initial current of 2500 mA for AA and 1000 mA for AAA.

All the batteries were discharged to 0.9 V. I got the following capacity results for new batteries.

Discharge graphs.

Then I gave the batteries a “rest” for 12 hours, charged them, again “gave a rest” and discharged them in the same modes. And so five times (the whole process took almost a month). I will not clutter up the article with a huge number of numbers and graphs, I will only show how the supplied energy fell as a percentage of the initial one.

The batteries that are discharged with high current pulses are best charged: after the first charge, they give 60-75% of the energy when discharged in the same mode, and even after the fifth charge they are able to give 39-43% of the initial energy. This and the following tables show the percentage of initial energy in watt hours after 1, 2, 3, 4, and 5 charges.

The batteries charge well even after a continuous discharge with a large current: 50-60% after the first charge, 24-32% after the fifth.

But after a discharge with a small current, everything is much worse. The FLARX AAA battery couldn’t charge at all once, GP AAA once charged and gave 36% of the initial energy, but couldn’t charge more. AA batteries gave 35-39% of the initial energy after the first charge, and then FLARX AA continued to charge and give 33-35% of energy each time, and GP AA almost could not be charged.

But energy is not everything. After charging, the batteries initially have a lower voltage and some devices will consider freshly charged batteries to be half discharged. I measured the voltage one minute after the start of the discharge.

New batteries discharged with low current initially have a voltage above 1.5V, but after the first charge their initial voltage turned out to be about 1.2V and many devices will rightly consider charged batteries to be “half-dead”.

In this and the following tables, voltage values in volts for a new battery (0) and after 1-5 charging, measured a minute from the beginning of the discharge with the indicated current, are indicated.

When the new batteries are continuously discharged with a large current, after a minute the voltage on AA batteries is about 1.4V, and on AAA batteries 1.3V. For charged batteries, this voltage is 0.2V less.

A similar picture is with batteries discharged by high current pulses.

The following was found out during the experiment:

– alkaline (alkaline) batteries can really be charged, and more than once;
– after charging, most batteries give from a third to two-thirds of the initial capacity;
– batteries that are discharged with high currents are best charged;
– the better the battery is initially, the worse it charges, as it gave maximum energy during first use;
– the charging process takes from 3 to 12 hours, depending on the state of the battery;
– the more energy was given by the battery initially, the worse it charges;
– for a successful charge, it is necessary that the voltage on a discharged battery be higher than 1 volt;
– During the experiment, not a single battery leaked.

Should I charge the batteries? And why not, but it hardly makes sense to charge them more than once. It seems to me best to use new batteries in devices with high power consumption, and when they “sit down”, charge them and install them in a device with low consumption, for example, in a watch or remote control.