Can we charge regular primary 1.5V batteries?

Can I charge LR6 AA or LR03 AAA disposable batteries?

We absolutely do not recommend charging typical 1.5V alkaline batteries. The LRXX designation refers to a disposable alkaline battery – and therefore a non-rechargeable battery.
There is a belief among our customers that when a given cell has a given capacity expressed in mAh, it is automatically associated with a rechargeable battery and the possibility of charging it. 

Meanwhile, the mAh unit determines both the capacity of any disposable battery and the rechargeable battery - it is measured from discharge under certain conditions (thus the disposable battery is already used up after such a test and can only be disposed of). By design, this value allows for a comparison of efficiency between some homogeneous power sources. The fact is, however, that this unit is given much less often with disposable batteries (why? – we explain in another post). In the case of many rechargeable batteries, however, providing the capacity in mAh is an obligatory obligation of the manufacturer – hence the perhaps more frequent association of this unit with rechargeable batteries.

After all, there are chargers on the market that can charge even standard, disposable 1.5V batteries.

Charging disposable batteries has been and is the subject of experiments, also in our internal lab. You can try to apply a constant current of 50-150 mA to a typical alkaline battery in the size of an LR6/AA and charge it this way until the voltage of 1.5-1.6V is reached...

But it really doesn't make sense - the more discharged the battery, the more difficult it will be to "charge" it this way. A battery charged in this way can store only part of its original energy and, perhaps most importantly, the risk of spilling such a battery increases dramatically.

Such "super smart" chargers, which supposedly can charge alkaline batteries, are nothing more than very simple constructions, with a very low charging current - there is nothing innovative about them, quite the contrary. We strongly advise against this type of invention, unless as part of experiments and fun ;-)