CHF17.70 CHF4.42/1pcs.
Panasonic eneloop pro
4 pcs., AA, 2500 mAh
Question about Panasonic eneloop pro
Hello and stupid question, what am I doing wrong: All the Eneloops I have (Pro and Weiss) neither retain their charging current (about 1-5 days after charging), nor do they last long in the devices (example, in the Netatmo thermostats the Pros last just under a week, while the Varta Longlive, for example, "last" half a year)... As a charger I use a 0815 Varta charger... Is that the reason...? I mean, these things should be just as good or at best better than 0815 batteries... right? Or am I making a mistake? LG and Merci.
Helpful answer
Netatmo thermostats = radiator thermostat?
What do you mean by "neither retain their charging current" and how do you measure that?
Rechargeable batteries are not batteries. The only thing that is identical in the case described here is the size. Apart from that, there are some technical differences, some of which make no difference, some of which do, as you can see here.
Not all devices that are operated with standard batteries (AA, AAA, etc) can be operated just as well with rechargeable batteries. One difference that does not work equally well is, for example, the different voltage.
Battery = 1.5V
Rechargeable battery = 1.2V
When using two cells in series, this even means 3V vs 2.4V. With more cells this difference gets bigger and bigger. Once you have this difference in mind, there is another difference that can also have an influence.
A full battery (alkaline) starts at 1.5 - 1.6V and discharges relatively constantly until it is considered empty at approx. 1.1 - 1.0V. However, depending on the device and application, the voltage for "battery empty" can also be higher. Which can be a problem when using rechargeable batteries. A rechargeable battery (NiMH) starts at approx. 1.3V and constantly holds 1.2V and then abruptly drops below this when it is empty. https://de.wikipedia.org/wiki...
There are devices that do not care about the slight difference in voltage and work exactly the same with rechargeable batteries. But there are others that do care. They do work with rechargeable batteries. But they do not last as long as you would expect. In the latter case, the battery is simply "empty" for the device because the voltage is too low to function. In another device, they would continue to function without complaint.