Finally restored my father's Ericssons; PF768, T10s & T18s! They're now fully working, with batteries that can keep them powered for a couple of days! Special thanks to u/MLP_George for helping me
Sony Ericsson Gf768 Battery - EMT Company – emtcompany.com
ERICSSON GF768 GF 768 ORIGINAL BLUE NEW REGENERATED + ORIGINAL BATTERY NEW | eBay