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
Amazon.com: Aluo 42T4880 New Laptop Battery for Lenovo ThinkPad X220 Tablet X220iT Tablet Serie 42T4881 42T4882 42T4877 42T4879 42T4880 42T4879 52 Only Use in The x220 Tablet Notebook 52+ 10.8V 63Wh 5600mAh :
Lenovo X220 X220i Tablet Battery
Lenovo ThinkPad 44+ Li-Ion 63Wh 6-cell Battery for X230 (0A36306)