Amazon.com: Lenovo ThinkPad 9 Cell Lithium Ion Battery 44++ ( Manufacturers P/N; 0A36307 ) 94Wh Extended Life System Battery For X220 And X230 Laptops Only : Electronics
Lenovo ThinkPad X220 Review - Notebook Reviews by MobileTechReview
Original Lenovo 9-cell Slice Battery 28 0A36304 94wh for sale online | eBay
Best Battery Life: Laptops That Last More Than 7 Hours
Amazon.com: Lenovo 0A36307 ThinkPad 9 Cell Extended Life Battery 44++ for Lenovo ThinkPad X220, X230 Models Only. (Caution: Not for X220 Tablet, X230 Tablet Models) : Electronics
PC | Internet Zone: Lenovo X220 Slice Battery 19+
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
ThinkPad X220 versus ThinkPad X230 with 19+ battery slice | Flickr