Another thing that's possibly going on is these are just bad batteries, and maybe even the charger.
I would never use any battery that didn't have a brand name on it that I was familiar with. These are likely generic batteries at best, which are unknown batteries of unknown quality made by unknown manufacturer. This now becomes a safety issue. If it was me the best place for those batteries are in the trash bin.
The charger sounds like a generic, too. Any decent charger will have some type of manufacturer's name on it.
This is, I would imagine, a common problem when buying a "kit" from an overseas vendor (I'm assuming here). Vendors skimp where they can, and including some cheap inexpensive batteries and charger is how they do it. Novices think they're getting a decent deal with such a kit, but often the batteries and charger are just junk.