Salvage Mobility Scooter Battery?

[YoshiMoshi]

I have some mobility scooter batteries that I believe to contain lithium ion cells. But there are no fasteners and I'm unsure how to crack them open. I also think they are lithium ion and not 100 percent certain. Any idea on how to open these and disassemble? I can't find anything online on how to open them.

These are the two models I have, both look similar.

Thank you!