Replacement lithium ion battery for Lenovo Thinkpad X220 X230 9-cells Replaces 45N1026 45N1027 45N1029 45N1175 42T4940 42T4942 0A36283 0A36307 Battery 29++ Battery 44++ Specs 10.8V 8400mAh 91Wh Warranty 18 months from date of purchase