Lenovo ThinkPad X220 Review - Notebook Reviews by MobileTechReview
Lenovo ThinkPad X220 really does get 20+ hours of battery life (sort of) - Liliputing
Just bought a quirky x220 slice battery. Looks exactly like a 19+, but says 20+. Works completely fine with 1% wear. Does anyone know what it might be? : r/thinkpad