Looks like a PJ996 lantern battery whose top cover broke off. It's probably carbon-zinc, in which case you can recover a decently big graphite rod from each cell.
What is this thing?
Let us help you identify that mysterious object you’ve found.
Currently in CHALLENGE mode: If you've got something obscure knocking about, post a picture, and let's see how we do. Please prefix such posts with "CHALLENGE:" so we know we've got a fighting chance.
I'd warn against opening the cells if you don't know how old it is. Modern ones are safe, older ones might contain heavy metals.
🤘
IDK, but you probably made the right choice by taking it home and bringing it inside your house. No chance it could be anything dangerous or toxic.
Ok, good. I was worried there for a second. Thanks!
Irony level "expert" 😂
Looks like a 6V alkaline battery, without the top. Here’s someone opening one:
Remains of what I know as a "camping battery". Six Volts, and loads of energy.
Someone was doing their part to keep the eels going
Remains of the battery from a lantern/marking buoy. Might contain heavy elements.
These used to be single use and dropped in the ocean upon replacement. More efficient light bulbs have replaced many with solar cells and wave generators, and better environmental awareness has stopped dumping these in the sea and they're instead recycled. At least here in Norway.
"Shit, this plastic vessel full of poison ran out... should we take it to shore and dispose of it properly?"
"Heavens no, just throw it directly in the ocean! Out of sight out of mind!"