You linked the Wikipedia page on electric batteries. Of course it’s going to talk about the things you put in your remote, because Wikipedia is not a dictionary and that’s what most people mean when they say “battery”. See also, the pages on energy storage that refer to them as batteries:

• https://en.m.wikipedia.org/wiki/Gravity_battery
• https://en.m.wikipedia.org/wiki/Thermal_energy_storage#Thermal_Battery

You could also look at the Wikipedia disambiguation page for “battery”, found at /wiki/Battery, which mentions electrochemical batteries as the most common meaning and then has an entire section on energy storage that mentions “Energy storage, including batteries that are not electrochemical”.

You are wrong.