Citizen Eco-drive H800 battery replacement tutorial.

Why battery need replace? It's eco drive isn't

That's very tiny, I expected the battery to be bigger

what it the battery used ?

I searched all over the Internet, but did not find the answer. Tell me, please, is it possible to replace the battery in Citizen EcoDrive BL5250-02L?

ALGUN DIA CITIZEN INVENTARA UN RELOJ QUE SE RECARGA CON LA ENERGIA ELECTRICA QUE PRODUCE EL CUERPO HUMANO . Y SERA PARA TODA LA VIDA .SERA INCREIBLE.