Old Segway - seeking help to get it revived

Hello Revspacers

For long and complicated reasons we have a Segway from ten or more years ago. This is afaik in good order mechanically and electronically. However the unit has been left without being plugged in for some years, and so the Lithium-Ion batteries are most likely in a fully discharged state.

I wonder if there is anyone in the Revspace community with good understanding of battery technology who could advise on what options may exist to revive this unit. And would be interested too from those with passion wrt two wheel dynamically balanced devices.

The main objective is to avoid this unit ending up in the E-waste!

This is the earlier type of Segway where the main pillar is rigidly attached to the foot board - and steering is done by a toggle on the handlebars (later models were steered by moving the main pillar to left and right).

Unit is at our house, less than 2km from Overgoo.

Thanks very much.